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Prof. (Dr.) Kulamoni Samal, an eminent Physicist of Odisha,
Former Professor and Head of the Department of Physics, University College of
Engineering, Burla, Sambalpur left for his heavenly abode at Cuttack on 17.02.2013.
He was 83. His demise is a great loss to our State and Country.
Prof. Samal's field of research includes Ultrasonics, Moleular Physics and
Condensed State of Matter. He went to Canada for post doctoral work on
Commonwealth Scholarship. He has about 50 research publications to his credit.
With a hobby of popularization of science from his student career he has published
about 40 books in Odia, 400 scientific essays and stories on topics like astronomy,
space science, lives of scientists, energy crisis, environmental science, development
of scientific temper etc. He has delivered about 300 talks in All India Radio and
T. V. and participated in many cultural functions of schools and colleges.He was
also the Founder Editor of the popular Odia Science Magazine, "Bigyan Diganta"
published monthly by Odisha Bigyan Academy.
Prof. Samal has received 'Best Popular Science Writer's Award' of 1993 fromOdisha Bigyan Academy. He was also felicitated by the Academy in 2007 as
'Senior Scientist'.
ODISHA BIGYAN ACADEMY, BHUBAESWAR
OBITUARY
W X
U V
3RD ISSUE3RD YEAR MARCH,2013
Science Horizon
Editorial Board
Dr Ramesh Chandra Parida
Dr Nityananda Swain
Dr Pramod Kumar Mahapatra
Dr Prahallad Chandra Nayak
Dr Bhabendra Kumar Patnaik
Prof. (Er) P.C. Patnaik
CONTENTS
Subject Author Page
1. Editorial: Senses, Sensors and Disaster Preparedness Sodananda Torasia 2
2. A Remarkable Steel and its Legendary Product inAncient India : Wootz & Damascus Swords Omkar Nath Mohanty 3
3. Cloning Animals (Concluding Part - Human Cloning) Amulya Kumar Panda 12
4. Exploring the Interior of Earth Sahid Ummar 15
5. Environment and Survival of Humankind :A People's Perspective S. N. Patro 20
6. Pondering on Water on World Water Day-2013 Manas Ranjan Senapati 25
7. Drops of Precious Liquid Kamalakanta Jena 27
8. Fire and Fire Extinguishers S. Acharya 31
9. Medium of Telecommunication Nikhilanand Panigrahy 34
10. Balanced Diet - Need for Good Health and Well Being Guru Prasad Mohanta 37
11. Migration of Birds - A Lengthy Journey Birat Raja Pradhan 40
12. Quiz Titaram Nanda Brahmachari 44
13. 5W'S+H : Sprain Nityananda Swain 46
The Cover Page depicts : Damascus Sword, Pattern-welded blades from multiple steels folded and forged
Cover Design : Sanatan Rout
President (In-charge), Odisha Bigyan AcademySj. William BilungEditorProf. (Dr) Sodananda Torasia
Language ExpertProf. (Dr) D. K. Ray
Managing EditorDr Rekha DasSecretary, Odisha Bigyan Academy
EDITORIALSENSES, SENSORS AND DISASTER PREPAREDNESS
Human beings are blessed with the senses ofsight, hearing, touch, taste and smell, essential to findfood and shelter and keep out of danger. However, incase of animals, nature has gifted them with othersenses for their survival. These include the ability toemit and detect supersonic sound pulses as in the caseof bats and whales. Some animals have infraredsensory organs, some have ability to produce electricfields/charge both for navigation as well as for killingtheir preys. As observed in many animals like honeybees, homing pigeons, migratory birds they have beenbestowed with magnetic sense, though the details ofthe mechanism of their use is not fully understood.
It is true that animals have the ability to sensedanger in advance which helps them to flee from thespot to protect themselves. Scientifically speaking theyare sensit ive to the slightest variation in theirsurroundings, be it sudden change in pressure of air orvariation in intensity of heat or light, or magnetic field.In such cases the speed of shifting from the scene isgreater than the speed of onslaught of the disaster.
For human beings the case is different. Takefor example cyclone, the information regarding animpending cyclone can be predicted and communicatedin advance before a limited time only. Depending onthe speed in which a cyclone advances to a location,people in that area may or may not have sufficienttime to take precautionary measures to save life andproperty. The case of disasters arising out of floodsand other disasters is somewhat different.
With development of science and technologythe concept of using defence mechanism by individualshas changed. The dangers faced by humans is on avery large scale in the form of disasters, either naturalor man- made. The former group includes cyclones,super cyclones, floods, earthquakes and tsunamis. Nocountry, however advanced in technology, is free fromdisasters. History is replete with the occurrence ofthese disasters over different parts of the Globeenumerating the wanton loss of life and property, notto mention the human suffering.
Even though disasters cannot be prevented byearly detection, timely communication and takingpreventive measures can minimize the loss. That iswhere advances in technology play an important role.
Tsunami, a very high ocean wave is producedby an undersea earthquake, landslide, or volcaniceruption. They frequently go undetected by shipsbecause the water takes about 10 to 30 minutes toreach it's highest level and fall back down.As a tsunamiapproaches a coastline, it can form a deadly wall ofwater that rises more than 30 meters high. A tsunamithat is caused by an undersea earthquake is also calleda seismic sea wave.
Scientists can calculate where and when a givenundersea earthquake would occur and predict whenthe resulting seismic sea waves will reach the shore.Thespeed of the tsunami depends on thedepth ofwater.
In recent years, with useof various sophisticatedinstrumentation such as Sea bottom pressure recorderswith satellite linked high speed and fast transmissionsystems and also broad band high sensitive seismicrecorders the event of occurrence of deep sea tsunamipotential earthquakes are very fast detected. Withadvanced modeling system and high performancecomputing (HPC) systems the possible propagationof tsunami waves and corresponding coastal disastersare predicted successfully and warnings are issued.
With satellite observational network, CoastalDoppler Radar system, high speed wind recordersand aircraft observation , quick and accuratemonitoring of severe tropical cyclones is possiblemuch before its landfall.
With very high resolution complex and coupledmeso-scale ocean-atmosphere models with very fastHPC system upto 3-5 days in advance severe tropicalcyclones and associated damage potentials are forecastand warning can be issued through all-weather friendlystable satellite based communication systems.
Thus high technology instruments andcommunication & computing platforms may be usedto detect initiation of natural disasters and time ofoccurrence and magnitude of phenomenon anddamage potential.
Advanced communication systems enablespeedy and timely dissemination of disaster events.This enables timely preparedness for appropriatemitigation strategies and reduce loss of life andproperty substantially.
Sodananda Torasia
3ScienceHorizon
MARCH, 2013
A REMARKABLE STEEL AND ITS LEGENDARY PRODUCTIN ANCIENT INDIA : WOOTZ & DAMASCUS SWORDS
Omkar Nath Mohanty
Introduction
India has had a rich heritage and tradition
in science and technology: in astronomy,
mathematics, medicine, metallurgy, ceramics,
textiles and so on. Its pre-eminence in
technology however got blunted with theindustrial revolution in Europe that led to
mass production with the advent of electricity
and new processes. India was known for its
metallurgical activities in the Copper & Bronzeage (ca.3000 B.C.) and is believed to be one
of the earliest to have ushered in the Iron Age
(ca.1000 B.C.); evidences of iron pieces from
inside the pyramids do however suggest that
the iron age could have existed along with or
even prior to the copper-age. Evidences for
iron production around 2500 years ago, inmany parts of India, are available.
The iron-base materials that the Indians
produced were of very high quality. Some ofthe outstanding example are:, the 'Wootz' used
for manufacturing the legendary 'Damascus'
blades with very sophisticated properties; the
Delhi Iron Pillar ( Gupta period ~ 400 A.D. )that defied corrosion in nature and the iron
beams used in the temples of Odisha
(1000 - 1300 A.D.), in particular in Konark
temple, that carried the weight of heavy
stone sculptures.
The subject of the Wootz Steel and its
famed product, the Damascus Swords shall
be covered in this article. Such swords
were known for their extraordinary sharp
edge as well as intricate patterns on the
surface. Many such swords are kept in
museums around the world. Several of these
swords are known to be of West-Asian
origin. There are also a number of examples
of Damascus swords with the characteristic
damask patterns in India; some of the
prominent ones are preserved in the armoury
of Golconda and Hyderabad's Nizam's; in
Tipu Sultan's armoury; Ranjit Singh'armoury,
and in Thanjavur and Maratha armoury. It is
also known that the mighty British were so
scared of the remarkably sharp and effective
swords used by the Indian sepoys in the
mutiny of 1857 that they decided to destroy
them, once the mutiny was quelled. Indeed,
they had to devise and make use of special
implements for cutting the Wootz metal
swords to pieces.
A broad discussion of the iron and steel
making processes in ancient / medieval India
would be made first and thereafter, the Wootz
steel / Damascus swords would be dealt with,
in order to comprehemsively appreciate the
entire subject.
4ScienceHorizon
MARCH, 2013
south India by a crucible process at several
locales including Mysore, Malabar and
Golconda in the 17th. century.
Wootz Steel and Damascus Swords -some broad observations
Several museums of the world preserv
and display the Damascus weapons. Broadly,
there are two categories of Damascus weapons
: one, the pattern-welded Damascus and the
other, the true Damascus, viz.Wootz Damascus
( some times, referred to as Oriental
Damascus). Both types reveal attractive surface
patterns comprising swirling lines of light-
etched regions on a nearly dark background.
The pattern-welded steels were produced by
forge welding alternating sheets of differing
compositions of ferrous materials such as
high- and low-carbon steels. This composite
used to be subjected to repeated fold /forge
cycles, twisted and manipulated until a large
number of layers was obtained and an
acceptable pattern revealed.
The "Oriental Damascus' or 'Wootz
Damascus' sword would show patterns as a
result of the inherent texture of a single steel.
The present article primarily focuses on this
Wootz Damascus. A typical sword and its
internal structure are shown in Fig. 1.
The Damscus sword revealing beautifulsurface patterns used to be made from high
carbon (~1.5 %) steels, the 'Wootz' steel.
The word 'Wootz' is believed to be derived
Making of Iron in Ancient India
It is believed that melting of iron was not
being practised in ancient India for want of
high temperature-enduring refractory in the
furnace that could hold molten iron (melting
point of pure iron,~15380 C). Instead, they
used to heat small fragments of iron ore mixed
with charcoal (produced from wood byburning), and blow air to raise the temperature
( probably ~11500 C)when the slag containing
the sandy materials and phophorus of the ore,
and possessing lower melting point, would
fuse. This is now a pasty mixture of porous
solid iron (the oxygen having been removed
by the reaction with carbon) and viscous slag,,
and was known as Bloomery Steel or Bloom.
When the Bloom is hammered in the hot
condition, the molten slag is squeezed outleavingalmost pure 'wrought' iron (mixed with
some remnant slag ) and can be further
converted into other shapes by hot working. If
the wrought iron is heated to high temperatures
( ~ 12500 C) in a closed crucible mixed with
charcoal, it picks up carbon and can form
steel. Avariety of steels from very low to high
carbon, were being manufactured in this
manner and are referred to in the Vedas. In the
middle ages the steels were being exported
fromIndia to overseas countries. For example,
there are accounts of export being made fromMalabar by Jewish merchants. European
travellers including Francis Buchanan and
Voysey reported the manufacture of steel in
5ScienceHorizon
MARCH, 2013
Fig.1: (b) The internal ('ladder & rose') pattern on thesurface of the sword
from 'ukku' used in Karnataka and Andhra
Pradesh to denote steel. Available accounts
suggest that Wootz steel from the southern
part of the Indian subcontinent was being
exported to Europe, China, theArab world and
theMiddle-East. Swords of very special quality
and perceived to be insuperable, were being
manufactured in a number of places including
Damascus, then a well-known centre of trade,
and in Persia from the Wootz steel being
brought from India. It is also known from
archaeo-metallurgical research that the king
Pourus gifted some quantities of Wootz steel
to his victor, Alexander the Great (~ 300 B.C.)
and also a sword made from this 'wonder
metal'. The great Indian warrior, Tipu Sultan is
known to have used Damascus swords. The
remarkable characteristics of Damascus steel
became known to Europe when the Crusaders
reached the Middle East, beginning in the 11th
century. They discovered that swords of this
metal could 'split a feather in midair; also
retain their edge through many a battle with
the Saracens'. The swords made from Wootz
Steel were easily recognized by a watery or
''damask'' pattern on their blades. Both the
origin of the swirling pattern and the
combination of unexpected strength and
toughness properties in such high carbon steels
have been the subjects of study by numerous
researchers. The exact process believed to
have been followed by the ancient Indians to
make Wootz metal and subsequently generate
the surface texture has been an area of
speculation and controversy during the last
decades and in spite of using sophisticated
instrumentsand methods,have failed to resolve
all issues. However, a simple description of
the processes adopted and a general
explanation of the characteristics would be
attempted in the present article; some relevant
references would be provided at the end for
readers who would be interested in going
deeper into the subject.
Method of Production of Wootz Steeland Swords
The Fig. 2 below ( adapted fromSherby's
work) depicts a conceptual scheme for making
of Wootz metal. It may be noted that, as stated
earlier, 'sponge' iron is made in the furnace
where the temperature is raised to ~12000C,
Fig.1: (a) A Damascus swordwith English translationofthe text
6ScienceHorizon
MARCH, 2013
the slag in a semi-solid condition that is mixed
with the iron is expelled by hammeringand the
product is a very low variety of carbon
(Wrought) iron. This product is again charged
into a furnace along with charcoal, held for
long periods again at ~12000C, cooled slowly.
The final product from this process, a 'cake'
weighing roughly 2.5 kg, is the Wootz metal,
containing very high (~ 1.3 - 1.6 %) carbon.
Such cakes were readily traded internationally.
Many of these materials were shipped to Syria
for being forged into swords.
strength-toughness properties in the finished
sword. The Fig.3 (a) and (b) show a schematic
of the forging and heat-treatment respectively.
The edge of the blade is expected to retain its
sharpness during long service.
The forging of the Wootz steel, a hyper-
eutectoid (carbon exceeding about 0.8 %
carbon) steel is possible if the material is
subjected to a strict temperature-time schedule
for developing the right microstructure in the
shaped sword.At a time when the instruments
for temperature measurement were not
available, adhering to accurate temperature
regimes was possible primarily by the colour
of the objects (dark-red, bright red, white etc.)
must have provided the right experience for
the artisans. Finally, a heat-treatment is done
with a quenching for imparting the right
Fig.2 : Conceptual scheme for making Wootz steel(Sherby)
Fig.3 :Schematic of Making of a Wootz Dmascus Sword :(a) Forgng schedule and (b) heat-treatment
( Sherby)
It is known that shipments running into
tens of thousands of wootz ingots were traded
from the Coromandel coast to Persia. This
would point to the fact that the production of
wootz steel was almost on an industrial scale
at a time far ahead of the Industrial Revolution
in Europe.
There is however a lack of unanimity
relating to the exact process adopted to
produce the final forging that would generate
the sword and its patterns, as shown in Fig.2
(a) and (b) respectively. It is now mostly
believed that that the Damascus sword making,
based on the Wootz metal, started quite early,
was already established by ~ 350 B.C. and
continued probably upto the 18th century and
the last genuine Wootz Damascus swords may
have been forged in theearly 1800s.Thereafter,
7ScienceHorizon
MARCH, 2013
the tradition of making these sophisticatedswords was somehow discontinued and the art
/ technology for doing the same is lost; needs
to be re-constructed.
Studies on Wootz Steel & DamascusSwords through the Ages
Most recorded scientific studies on
Wootz steel / Damascus swords were carried
out by western scientists. Some of theprominent of them would be dealt with here.
One of the earliest studies was by the Italian,
Giambattista Della Porta, the best-knownnaturalist of his period, from Venice. In 1589
his observation on Wootz was, "too much heat
makes it crumble"; thereby recognizing the
influence of temperature on this special metal.Thiswas followed by Joseph Moxon's work in
England in 1677 who found that forging this
steel above a red heat would be risky. Theexperiments that generated great interest in
studying Wootz steel in the early 18th century
were those of Antoine Reaumur, a Frenchscientist-cum-philosopher.who wrote about
Wootz steel in 1722 in his 'Memoirs on Iron
and Steel', recognized to be one of the
earliest books on iron, in history. Reaumurwrote about the strange 'cake of steel' from
India among the steels from Cairo, Egypt
where Damascus swords were available.According to him the steel from India was
very special and he could not find a black
smith in Paris to fashion a sword from it.
From this account, it would be noted that the
forging process for Wootz metal, that involved
identifyingan optimumwindowof temperature
was not known to the scientists in Europe yet.
A Swedish metallurgist, Rinman showed in
1774 that while wrought iron dissolved in acid
completely, Wootz Steel does not and a residue
remains that was identified as carbon.
Sometime later, the well-known chemist from
Sweden, Bergman could quantitatively
differentiate between wrought iron, steel and
cast iron based on carbon content. In a way
therefore, work on Wootz Steel introduced
the concept of adding carbon to iron for
producing a range of ferrous alloys.
The Swedish studies generated a good
deal of interest among the leading researchersin ferrous alloys and in particular in Wootz
metal. A British researcher, George Pearson
in 1795 reported his work on 'Bombay Wootz' at the Royal Society; his hypothesis was that
the characteristic properties of Wootz were
due to the presence of oxygen. Mushet in U.K.was one of the first in 1804 to correctly
conclude that there was more carbon in Wootz
steel than in common steels from England.Stodart in U.K. succeeded in forging Woootz
steel. Indeed, he used Wootz to make knives
(he had a cutlery business ) and found that theypossessed very fine cutting edge, superior to
any other. Faraday who later developed to be
one of the greatest physicists the world hadknown, joined Stodart and the two together
conducted research on Wootz between 1819
8ScienceHorizon
MARCH, 2013
and 1822 (before he moved to the field of
electro-magnetism ). They experimented with
a number of additions to steel. On the natureof Wootz however, Stodart and Faraday
incorrectly concluded that alumina and silicaadditions contributed to the exceptional
properties of the steel. The Russian scientist
Anossoff who was working during 1840s onthe Bulat steel (similar in some ways to Wootz)
devoted his entire life time in trying toreproduce the properties of Wootz for
manufacture of articles requiring sharpness
suchasploughshare, couldnot achievehis dream.
Serious research work on genuineDamascus swords could start only in about
the first quarter of 1900 when a few swords
and daggers from Wootz steel were madeavailable to Zschokke, by a large private
collector called Henri Moser (this private
collection is on display at the Berne HistoricalMuseum, Switzerland) for conducting a
scientific study; Zschokke conductedhis workand published his paper in 1924 on the
Damascus swords.
A fascinating series of work was started
by Prof. Sherby of Stanford University in1970s. While Sherby and co-workers were
engaged in developing super-plasticity(exceptional elongation at an elevated
temperature) in high carbon steels, they
stumbled upon the information that Wootzsteel, like their material, was very rich in
carbon. Sherby's first major article on the
subject appeared in 1979. Sherby &
co-workers meticulously compared theproperties in Bulat and Damascus steels with
their own ultra high carbon steels, amenable
to super-plasticity. The introduction of high
ductility in the Damascus blades was well
elucidated by Sherby & Wadsworth. The
differentiation between the genuine Damascusblades and the pattern-welded material was
done by them. According to their work, the
patterns on the Damascus blade was due to
carbides, primarily iron carbides ( Fe3C );indeed a scheme for carbide precipitation goes
by the name of Wadsworth-Sherby (W-S)
mechanism. One of their many publications
was in Scientific American (1985). Sherby &
co-workers have continued to work into the
early 2000s. One of the co-workers, Taleffcontinued work on Damask patterns at the
Univ. of Texas - Austin.
Meanwhile, another series of researchwork was started by Prof. Verhoeven at the
Iowa State Univ. He received some of the
samples from the Zschokke swords.A forging
expert from Texas, Pendray jointly workedwith him r forged by them that replicated the
properties and appearance of the ancient
Damascus blades.According to their research,
in order that the patterns appear in the etched
condition, one needs strong carbide forming
elements such as V, Cr, Mo etc. and precisethermo-mechanical treatments (i.e. heating and
forging temperatures) to take care of the
9ScienceHorizon
MARCH, 2013
higher phosphorus contents in the Wootz
material, that ostensibly came from the ore.The presence of small quantities of V wereobserved by them in the Sorel Pig Iron that
they were using for their own compositions aswell as in the Wootz. It would appear thatsome of the south Indian ores, particularlythose from areas in Karnataka contain small
quantities of the strong carbide formingelements such as V, Cr. Afascinating paper by
Verhoeven appeared in Scientific American(2001). The experiments by Verhoeven haveshown through sophisticated analysis, themechanism through which carbide particles
form various patterns. The mechanismproposed earlier by Wadsworth-Sherby (W-S)was not adequate to explain the exact pattern-formation on the Damascus blades, as
Verhoeven showed. An arrangement ofcarbides, seen at a magnification of ~500 X isshown below, in Fig. 4,These would form the
typical ladder and rose patterns of Fig. 2.,
during cyclic forging, accordingto Verhoeven.
However, there are still some openquestions regarding the process adopted by
Verhoeven & Pendray and that used by the
ancient Wootz Steel producers and Damscus
blade makers. Verhoeven adopted 'melting'of the metal that formed 'dendrites' (tree-
like structures) on solidification and the
presence of V (or other carbide forming)'impurities' ahead of the dendrites produced
the pattern later on, after forging. The
ancient Wootz steel producer probably couldnot resort to melting because of limitation
in the highest temperature that the available
crucibles could attain.
Wootz Steel as an Advanced Material
As has been mentioned, Wootz isprimarily a high (~ 1.5 %) carbon steel that is
inherently brittle. However, when subjected to
an optimized temperature-time--working(thermo - mechanical) regimen, the thin and
long damaging carbides are converted into
spherica lly-shaped (globular) carbideschanging the characteristic of the material
completely. Thus, the presence of globular
carbides in the ferrite matrix (background)
impart the desired ductility to this steel andalso help Damascus swords retain their sharp
edge for long. It is remarkable that the basic
principles of a modern technological process,viz. super-plasticity (display of several hundred
percent of elongation at a suitable temperature,
typically around half the melting point) could
have been practiced (perhaps developed
Fig. 4 : The microstructure of Damascus Bladesshowing the arrangement of carbides
(Verhoeven)
10ScienceHorizon
MARCH, 2013
empirically) at such an early age, in Wootz
steels. It is known that the two important pre-
requisites for a material to possess super-
plasticity are : (i) presence of two phases and
(ii) fine grain size. The processing of Wootz
steel used for making Damascus swords,
apparently fulfilled these conditions (i.e.
extremely fine spherical carbide particles in
the background, very fine ferrite grains). Some
work in this direction on a material similar to
the Wootz / Damscus steel was carried out by
the author at the NML,Jamshedpur. The Fig. 5
we could achieve as high as 1200 percent
elongation; this is an example of super-plasticbehaviour in a material. Typically, the steeldisplaying super-plastic behaviour at anelevated temperature shows over 15%elongation at room temperature at a high(tensile) strength of over 120 kg/mm2 . These
are considered excellent combinations ofstrength and ductility for an engineeredmaterial, such as a sword. Another specialfeature, discovered in recent times in theDamascus sword material, is the presence ofnano-particles (a nano meter is one billionth
of a meter). As is known now, nano-features(particles as well as general microsturctures)are the cause of very special qualities in manymaterials and components, some examplesare the stunning colours in ancient potteries,murals, stained glass windows of medieval
churches in Europe and so on. The use ofnano-silver/copper particles for waterpurification is a more common currentexample. Indeed, the modern world is excitedabout the unlimited possibilities with use of
Fig.5 : Long, thin carbides in the cast condition,turned to fine globules after working
( the marker scale shows the dimension of 5 micronsfor comprehending the size, ONM)
shows the presence of long carbides in the as-cast condition, that after the hot working gettransformed to fine globular shape in the ferritematrix. The result of the microstructure onthe properties is phenomenal. The intrinsicallybrittle material can now be stretchedappreciably at a temperature of 760 - 800? C.For example, in Fig.6, one could see that theelongation (increase in length over originallength expressed in percent) in a test piece hasbeen 500 percent. Indeed, by optimizing thecondition of processing of the steel further,
Fig.6 : Super-plastic behaviour in the test piece : theelongation percent is ~ 500% (ONM)
11ScienceHorizon
MARCH, 2013
nano materials, more so in bio-medical worldas sensors, drugs and in drug-delivery systems.
In Damascus swords, the discovery of nano-
carbide particles aroused a good deal of
renewed interest in this ancient material. sincethe impact of such extra-fine particles on the
bulk properties of the Damascus swords are
yet to be elucidated. In the journal Nature, ateam led by Paufler from Dresden University,
Germany, have recently reported that apart
from nano-wires it has also discovered carbonnanotubes in the sword-the first nano-tubes
ever found in steel, The nanotubes, which are
remarkably strong, run through the blade's
softer steel, likely to make it more resilient.
Conclusion
Wootz steel bearing ultra high (~ 1.5 %)
carbon and its final product, the insuperable
Damascus swords, represent fine examplesof the technological advancement in ancient
India and the superiority of India over other
countries, in terms of such engineeredproducts at that period. This know-how was
however lost in course of time due to lack of
documentation and also due perhaps to the
fact that raw materials became scarce. Thework done by an impressive list of researchers
in a number of countries and over a long
period has helped understand the theory andpractice of manufacturing these advanced
materials. Although bulk of the features of the
Wootz metal and the Damascus swords havebeen scienti fica lly explained through
meticulous research over the past two decades,the understanding about finer aspects such asthe nature of carbide precipitation responsiblefor the surface pattern are still a matter ofspeculation. It is also amazing that the modernconcept of super-plasticity and nano-structures were part of these ancient materialsthat provide enough inspiration to today'sresearchers.
Selected Bibliography[1] O. D. Sherby. Damascus Steel Rediscovered? :Trans.
ISIJ, 19 (1979) 381{390.[2] O. D. Sherby and J. Wadsworth : Damascus Steel.:
ScientificAmerican, 252(1985) 112 {120.[3] J Bhattacharya,B N Ghosh,S K Choudhury,S P
Chakraborty,PK Deand O N MohantyScandinavianJournal of Metallurgy, 21 (6), (1992), 279{283
[4] J. D. Verhoeven and A. H. Pendray. Studies ofDamascus Steel Blades: Part I Experiments onReconstructed Blades : Mater. Char., 30 (1993)175{186.
[5] J. D. Verhoeven, A. H. Pendray, and P. M. Berge.Studies ofDamascus Steel Blades: Part II Destructionand Reformation of the Pattern: Mater. Char.,30(1993)187{200.
[6] O. D. Sherby and J. Wadsworth. Damascus Steeland Superplasticity {Part I : Background,Superplasticity, and Genuine Damascus Steel.:SAMPEJournal, 31(1995) 10{17.
[7] O. D. Sherby and J. Wadsworth. Damascus Steeland Superplasticity {Part II: Welded DamascusSteels.: SAMPE Journal, 31 (1995) 32{39.
[8] J. D. Verhoeven. The Mystery of Damascus Blades.ScientificAmerican, (2001)74{79.
[9] E.M. Taleff : Microstructural Characterization of aKnife with DamaskPatterning Technical Reportsubmitted to The University of Texas, Austin,Department of Mech.Engg. (2003)
[10] S.Srinivasan and S.Ranganathan: India's Legendary'Wootz' Steel: An Advanced Material of the AncientWorld : Pub. Tata Steel ( 2004 )
Former Vice-Chancellor,
Biju Patnaik University of Science & Technology,Presently : Director, Technology & Academic Initiative,
RSB Metaltech., RSB Group.Plot 200; Unit 3; Kharavela Nagar, Bhubaneswar - 751001
12ScienceHorizon
MARCH, 2013
CLONING ANIMALS(Concluding Part - Human Cloning)
AmulyaKumarPanda
Aliver Toffler, in his 1970 book "The
Future Shock" predicted that"Man willhave to
make biological carbon copies of himself." As
a great author as well as a reputed and
respected sociologist, he observed with
concern the changes contemporary society
was pass ing through owing to rapid
industrialization. It was this concern that drove
him to make such a prediction, which,
considering the progress then made in cloning
animals, appeared to be a distinct possibility.
Less than two decades back Robert Briggs and
Thomas King (1952) and one decade back
John Gurdon (1962) had cloned the leopard
frog Rana pipiens and the South African
clawed frog Xenopus laevis respectively. "The
Future Shock", a non-fictionwritten by a highly
influential writer, had its impact on the society,
at large, and the scientific community, in
particular. Its immediate effect was there to
be seen; the term 'Clone' as used by Haldane
in 1963 for animals created by out-of-the-
Nature methods, suddenly gained popularity.
More than that, the changing attitude and
approach of the scientists to human cloning
was clearly felt.
Taking advantage of the changing scenario
quite a few unjustified and not so scientific
claims were made about human cloning, some
even declared that they not only knew that it
has happened but have already seen the clone
in person! One such instance was a matter of
great controversy when in 1978, David Rorvik
publishedhis book "In HisImage : The Cloning
of a Man". In this book the author stunned the
world with the information that an American
billionaire, with the help of a doctor, has
already got his own clone created. Rorvik
claimed to have seen this clone. This caused
tremors in the world of science as well as in
social life. The matter went to court of law
where it was dismissed finally as the author
was unable to substantiate his claim.
Toffler's influence was also evident in
the celluloid world when films were made
based on some bestsellers. "The Boys from
Brazil", made in 1976, was on making copies
of Hitler. In 1991 "Jurassic Park" was made
on the same theme - cloning, this time
Dinosaurs. The message from such films,
loud and not very clear was - it is possible to
create bloodthirsty, murderous people and
unleash unimaginable terror in the world; it
is also possible to bring back to life some of
the extinct species. By and large, the situation
was somewhat confusing, rather perplexing,
until Dolly, the cloned sheep emerged on the
scene in 1996 and created history.
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Dolly's arrival triggered cloning efforts
pertaining tomammalsand particularlyhumans.Statements like "…. Human cloning is jut a
couple of tweaks away" (Robert Forman,Reproductive Medicine Centre, London) and
announcements by some scientists (RichardSeed, Physicist, Harvard University) to get
themselves cloned were rather commontowards the end of the century. Even many
commoners nursed dreams about cloning theirnear and dear ones or themselves. With this as
the back-drop, 'Clonaid', a science-based firmestablished a laboratory in 2001, specifically
for creating human clones. This was just anindication of things to come. A year, later
Brigitte Biosseler, a biochemist and theDirector, Clonaid announced that a human
clone has already been created by Cloanaid on26th December 2002. Following the Dolly
technique Clonaid scientists took a nucleusfrom a somatic cell of a certain American
gentleman and placed it in a enucleated egg of
his wife. In due course they got the clone, a
baby girl, and named her 'EVE'. 'Clonaid' also
claimed to have produced four more human
clones by 2003. This included the clone of the
dead son of a Japanese couple. Meanwhile,scientists round the world were making
attempts to clone mammals and even a fewwere trying to clone man.
Reports were pouring in, but the attemptmade by 'Advanced Cell Technology'-Act in
2001 before Clonaid's announcement about'EVE', was rather encouraging. In this venture,
the firm could achieve only an early humanembryo (six cells) following a somewhat
modified Dolly technique, but its Vice-
President, Robert Lanza was highly otpimistcabout it. He proclaimed that this success paves
the way for 'Therapeutic Cloning' andemploying this method stem cells could be
harvested for making organs for organ
transplantation as well as for treating injuredorgans and diseases. Therapeutic cloning was
pro jected as more uti li ti ta ri an than
straightaway cloning man or other animals,which is called 'Reproductive Cloning".
While claims and counterclaims were
being made and debates and discussionscontinued about the desirability and ethics of
human cloning, the announcement made by
Severino Antinori, an Italian fertility doctorand embryologist, created a storm. Antinori's
success story began in 1994 when he wastreatinga 62year oldwoman. She was 'infertile'
- a barrenwoman and had nochildren.Antinori's
treatment helped her attain motherhood. WithHuman Clones ... A Computerized Artwork
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this Antinori hit the headlines and begandreaming big things … to make human clonesto help childless couples. He joined handswith Brigitte Boisselier and a Kentucky
University reproductive biologist, PanayiotisZavos. In2001 ina meetingof theUSAcademyof Science, in the presence of his associatesand all the delegates and members, declaredhis determination to create human clones.This stirred up a hornet's nest, but Antinoriwas obstinate and adament. He and hisassociates ('the unholy trio'?) continued withtheir work. From time to time Antinori madesensational announcements on the issue. One
such is, he has already created three humanclones - two boys and a girl, sometime in thebeginning of this century and they are nowliving in some European country. In themeantime Boisseleir and Zavos have leftAntinori's company and are going ahead withtheir work of human cloning separately. Theidea is simple - each one of the trio wants tobe the first successful human cloner!
Accordingly, they make some confusing, ifnot bizarre announcements, independent of
one another, on their success. But one thing iscommon about them - none of them has beenable to substantiate their claims.
Human cloning is a sensitive issue,
besides being risky. Accordingly in most ofthe countries including India and in the U S itis banned. In some countries only therapeuticcloning research is permitted. Those who arein favour of cloning man argue that it is a
simple, safe way of helping couples who
cannot have children normally and naturally.But the technique itself is not safe. Mercy
killing of Dolly is a sad, pathetic pointer tothis. Many really safe options like in vitro
fertilization (test-tube baby) are available.Besides there are several socio-psychologicalissues that pose tricky problems.
The clone is a genetic carbon copy ofthe 'cloned', a look-alike. But it may not be the
same as the cloned in all respects. The desiredresults, therefore, may not be obtained.
Besides, what would be the family-relationshipof the clone and the cloned? … Father and son(or Mother and daughter), or Identical twins
separated by time ? What psychological impactwill this have on the clone ? What will be his
or her identity … somebody's clone ! Whatwill be his or her position in the society ?
Would the society accept a clone as a normalindividual ? These and countless otherquestions need to be addressed, the techniques
have got to be improved and made foolproofand the whole issue has got to be debated, if at
all we want to go for human cloning.
Questions like this might have appeared
irrelevant with regard to Dolly, the clonedsheep and that is why she was put to sleep so
easily in 2003. But can we afford to beindifferent to human cloning issues and canwe consider such questions about a human
clone irrelevant ? The argument that we can gofor therapeutic cloning is also losing weight.
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Clone a human embryo, take out the stem
cells and then destroy it calling it just a lump
of cells- is it ethical ? Those who say so, what
were they when they were in the blastocyst
stage or a little beyond ? Were they also notjust 'a lump of cells' !
With John Gurdon and ShinyaYamankawinning the 2012 Nobel Prize in Physiology
or Med ic ine, eth ical conside ra tions
concerning harvesting embryonic stem cells
from cloned human embryos have become
rather inconsequential. Their contributions, as
well as the research findings like JamesThomson and many others have shown that
adult cells could be reprogrammed i.e., they
could be brought back to an embryonic state.
Such cells could be made to develop into adiverse vari ety of cel ls as th rough
reprogramming they once again become
'pluripotent'. They are, therefore, called
'induced pluripotent stem cells' (iPSC's).
In December 2012, Gurdon predicted
that it may be possible to clone man in another
fifty years or so. But just because we can do a
thing, should we do it ? Should we go forhuman cloning at all ? ?
Reference1. Developmental Biology, Scott F. Gilbert (2006).2. Developmental Biology, Leon W. Browder (1980).3. Cloning : Kali Aji O Kali, (Odia) A. K. Panda (2007).4. Nobel Committee Press Release, 8.10.2012.
73, Co-operative Colony, Post-KIIT, Bhubaneswar-751024
Mob. : 9937440390, 8280239957e-mail : [email protected]
EXPLORING THEINTERIOR OF EARTH
SahidUmmar
Introduction
Since time immemorial, man has always
tried to imagine about the interior of the Earth
on which he lives. He wonders of what the
Earth is made up of ! How would it be like to
journey to its center ? In school days, we are
often told, if we dig a tunnel vertically, then
we can reach America lying on the other side
of the Globe. But it is actually a fun to pretend
that man can dig any tunnel to the other side of
the Earth. Scientists have proven that man can
never be able to dig through the center of the
Earth, because the center is so hot that man
can never survive there.
However, he is always eager to explore
the interior of Earth. Though scientists have
not yet been able to enter into the interior of
Earth for even more than a few meters, they
have conceived a lot of ideas about it from the
information collected through some indirect
methods. Most of the current information
about the interior of Earth is from the studies
of the path and characteristics of the seismic
waves travelling through the Earth, due to the
vibrat ions generated naturally by the
earthquakes within its body. These seismic
waves indicate about its interior in several
general ways.
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measurement of the earth's mass and
consequently its density. The densities ofmaterials in the interior of Earth have been
estimated for different depths by differentscientists. According Keith Edward Bullen
(1906-1976), the density of the uppermostpart of the Earth i.e. the crust is between 2.5to 3.0 gm/cm3, whereas that of the middle part
i.e. mantle is 3.0 to 5.5 gm/cm3 and in the corebetween 9 to 11.5 gm/cm3.
Temperature
Now let us first consider the temperatureprevailing within the interior of Earth. Since
ancient days, man is well experienced with thetemperature prevailing inside the Earth. He
has experienced it from volcanic explosionsand hot springs. The people in some of the
cold countries also dig tunnels and live insidethose to protect themselves from severe cold.In other places, people feel more hot inside
deep wells or underground mines. In general,the temperature within the Earth increases
with depth. The rate of temperature thatincreases with depths has been estimated tovary from 100C to 500C per km, the average
rate being 300C per kilometer.
A number of advances in the field ofphysical sciences took place before anyassessment for distribution of pressure within
the earth was possible. Newton's gravitationallawprovided thesteppingstoneforthis venture.
Results of the study of seismic wavepropagation in the form of density distribution
To understand what's deep in the Earth is
a great challenge. Accumulated and detailed
seismic studies, coupled with theoreticalspeculations have suggested the interior
structure of Earth, the depth of different layers,temperature, pressure, chemica l and
minera logical composition, etc. The
knowledge about the layering and chemicalcomposition of Earth is steadily being
improved by the Earth scientists throughgeological observation of surface rocks as
well as their studies by laboratory
experiments at high pressure and temperatureconditions and analyzing earthquake records
on computers.
Density
Scientists have predicted a number of
estimates about the density of the Earth. Thefirst scientist who considered this aspect three
hundred years ago was Sir IsaacNewton (1642-
1727). From his studies of planets and theforce of gravity, he calculated that the average
density of the Earth is twice that of surface
rocks. He imagined that the Earth's interiormust have been composed of much denser
material. He predicted the density of Earthfive to six times more than that of water. In
1798 , Henry Cavend ish (1731-1810)conducted some experiments and proved the
prediction of Newton. Basing on his
experiment he also calculated the averagedensity of the Earth to be 5.48 gm/cm3.
Evaluation of gravity has prompted the
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yielded a hypothetical pressure distribution
model of the earth's interior. The temperatureof the inner core can be estimated byconsidering both the theoretical and the
experimentally demonstrated constraints onthe melting temperature of impure iron at thepressure which iron is under at the boundaryof the inner core (about 330 Giga Pascal),
which is more than three million times that ofatmospheric pressure. These considerations
suggest that its temperature is about 5,430 °C.
Interior Structure
Scientists have been able to identify
several layers in the interior of Earth withunique chemical and seismic properties. It ismade up of three main shells: the very thin,brittle crust, the mantle, and the core; the
mantle and core are each divided into twoparts. Although the core and mantle are aboutequal in thickness, the core actually forms
only 16 % of the Earth's volume, whereas themantle occupies 82 % percent. Thecrust makesup the remaining 1-2 %.
Crust
Crust is the solid outermost layer of the
Earth. The maximum thickness of this layer isabout 60 kilometers, which is found at Pamirplateau. Its thickness is much less at oceanfloor. The average thickness of this layer is 33
kilometers. The crust is divided into two thinlayers by Conrad discontinuity (named afterVictor Conrad, 1876-1962), present at a depth
of 22 km from the surface between the
Continental Crust (35-70 km) and the OceanicCrust (5-10 km). The crust is composed mainlyof alumino-silicates. The outer thin layer isknown as Sial, composed of more siliceousrocks like granites and granodiorites. Virtuallysial is the combination of the names of twoelements Si (Silicon) and Al (Aluminium). Itmeans the Silicon and Aluminium dominatethis thin layer. The inner layer of the crust isSima, composed of the two dominatingelements Silicon and Magnesium. The rocksfound in this layer are less siliceous rockslike gabbro, basalt, etc. F. W. Clarke (1847-1937) calculated that a little more than 47%of the Earth's crust consists of oxygen. Themore common rock constituents of the Earth'scrust arenearly alloxides andchlorine, sulphurand fluorine are the only important exceptionsto this and their total amount in any rock isusually much less than 1%.
The boundary between the outer solidCrust and underlying highly viscous Mantle isthe Mohorovicic discontinuity (or Moho),named afterAndrija Mohorovicic (1857-1936)who identified it. Though no one has ever seenthis boundary, it can be detected by a sharpincrease downward in the speed of Earthquakewaves there. The cause of the Moho is thought
to be a change in rock composition.
Mantle
Mantle is the largest second layer in theinterior of the Earth. This is where most of theinternal heat of Earth is located. It constitutesabout 82 percent of volume and 66 percent of
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the mass of the Earth. Experimental evidence
shows that, up to a depth of some 2900 km,shear wave movements are observed; material
in this region is apparently rigid enough to
allow such movement. The uppermost mantle
and overlying crust are relatively rigid andform the lithosphere, an irregular layer with a
maximum thickness of pe rhaps 200
kilometers. Below the lithosphere, the uppermantle becomes notably more plastic.As such
two main zones are distinguished in the upper
mantle, i.e. the inner asthenosphere composedof plastic flowing rock about 200 km thick,
and the lowermost part of the lithosphere
composed of rigid rock about 50 to 120 km
thick. Important changes in crystal structurewithin the mantle occur at 410 and 660
kilometers below the surface, spanning a
transition zone that separates the upper andlower mantle. While in the upper mantle the
silicates generally remain both hot and underrelatively little pressure, it has a relatively lowviscosity; but on the other hand, the lowermantle is under tremendous pressure and hasa higher viscosity than the upper mantle. Onthe basis of the studies so far done, it ispresumed that the mantle is composed mainlyof ferro-magnesiumsilicate rocks like dunite,peridotite and eclogite, which are rich in ironand magnesium relative to the overlying crust.
Core
The innermost layer of the Earth is theCore. The Core is separated from the Mantleby Gutenbergdiscontinuity (named after BenoGutenberg, 1889-1960). The total thicknessof the Core is about 3470 kilometers. Thislayer is about 16 percent of the volume and33.5 percent of the mass of the Earth. Thecore was the first internal structural elementto be identified. It was discovered in 1906 by
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R.D. Oldham (1858-1936), from his study ofEarthquake records, and it helped to explainNewton's calculation of the Earth's density.Seismic measurements show that the core isdivided into two layers with a transition zonein between. The outer core is presumed to beliquid because it does not transmit shear (S)waves and the velocity of the compressional(P) waves that pass through it is sharplyreduced. The inner core is considered to besolid because of the behavior of P and S wavespassing through it (in 1936) the Earth wasdiscovered to have a solid inner core distinctfrom its liquid outer core, by the seismologistInge Lehmann (1888-1993), who deduced itspresence from observations of earthquake-generated seismic waves that reflect off theboundary of the inner core and can be detectedby sensitive seismographs on the Earth'ssurface. This boundary is known as the Bullendiscontinuity, or sometimes as the Lehmanndiscontinuity. The thickness of the liquid outercore is 2082 km. The thickness of the middlelayer of the core is about 130 km, which is insolid state. The transition between the innercore and outer core is located approximately5,150 km beneath the Earth's surface. Theliquid outer core surrounds the inner core andis believed to be composed of iron mixed withnickel and trace amounts of lighter elements.Recent speculation suggests that the innermostpart of the core is enriched in gold, platinumand other siderophile elements. The thicknessof the innermost layer of the core is about1258 km, also present in solid state. It is
composed of heavy elements. As per latestinformation the density of this layer has beenestimated to be between 9.47 to 18 g/cm3.Theinner core is solid due to the overwhelmingpressure found at its center. The core is thusbelieved to largely be composed of iron (80%),along with nickel. The temperature of theouter core ranges from 4400 °C in the outerregions to 6100 °C near the inner core. It isbelieved to consist of an iron-nickel alloy.The Earth's inner core is slowly growing as theliquid outer core at the boundary with theinner core cools and solidifies due to thegradual cooling of the Earth's interior (about100 degrees Celsius per billion years). Manyscientists had initially expected that, becausethe solid inner core was originally formed bya gradual cooling of molten material, andcontinues to grow as a result of that sameprocess, the inner core would be found to behomogeneous. It has even been suggested thatEarth's inner core might be a single crystal ofiron. Earth has a modest magnetic field producedby electric currents in the outer core.Convection of liquid metals in the outer corecreates the Earth's magnetic field. Without the
outercore, lifeon Earth would bevery different.
Reference1. Structure of the Earth - Wikipedia, the free encyclopedia
http://en.wikipedia.org/wiki/Structure_of_the_Earth
2. About the Earth's Core - Its Structure and PossibleCompositionhttp://geology.about.com/od/core/a/about_the_core
Former Senior Geologist, Geological Survey of India
VIP-130, Ekamra Vihar, [email protected]
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ENVIRONMENTAND SURVIVAL OF HUMANKIND:A PEOPLE'S PERSPECTIVE
S. N. Patro
Introduction
About two decades ago in June 1992, the
United Nations Conference on Environment
and Development (UNCED, the Earth Summit)
was held in Rio de Janeiro, Brazil.Attended by
the representatives of about 192 countries it
was the largest global conference on
environment at that time. The "Rio Declaration
on Environment and Development" was
followed by adoption of two historic
conventions namely- the 'United Nations
Framework Convention on Climate Change-
UNFCCC)' and the 'Convention on Biological
Divers ity-CBD'. These two important
conventions may find solutions to meet the
challengingneeds for the survival of mankind.
The UN mechanism plays the facilitating role
only, and does not have any legal teeth or
muscular power to contain any nation. For a
layman to understand it can be explained that
the progressive change of climate impacts the
natural environment and the very sustenance
of life on earth. The climate change was a
natural phenomenon, and necessary for the
course of evolution. But the unrestricted
anthropogenic activities of the modern man
add more green house gases to the atmosphere
making the hitherto habitable climate
inhospitable posing threat to the very survival
of mankind. Hopefully, every nation now
understands the adverse impact of climate
change and expresses concern.
Energy Intensive Modern Lifestyle
The Asahi Glass Foundation, Japan has
been conducting the citizen's survey on
'Environmental Problems and Survival of
Humankind' since 1992, following the Earth
Summit. The Foundation made an interesting
observation in the survey it conducted in 2012.
It was regarding the 'Technology that needs to
be Cultivated Urgently". This mostly refers to
power generation and energy conservation to
meet the surging demand of energy for the
modern lifestyle. The respondents of the
survey most frequently chose' Solar Power' in
preference over other sources like nuclear
energy, wind energy, geothermal energy,
hydro-power energy, wave energy, tidal energy,
etc. (Table-1). The solar power mechanism is
nothing but the reflecting mirrors concentrate
the solar energy to boil water into vapour
which is usedto rotate the turbine and generate
energy. The only demerit in solar power plant
is that it requires about three times the land
required for coal-based thermal plant. Further
research may invent devices which may reduce
land requirement in near future. According to
a study made by the Scientists of the Indian
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Institute of Science (IISc), Bangalore, that the
country's energy needs can be met entirely by
solar and other renewable sources and 4.1 per
cent of the total uncultivable and waste land
area of India will be enough to meet the
projected annual demand of 3,400 terawatt-
hours (TWh) by 2070 through solar energy
alone (1 TWh per year equals114 megawatts).
'Plant' is nature's living equipment which has
the very simple mechanism of harvesting
solar energy. The chlorophyll in the leaf is so
designed that it traps solar energy, water
from soil through the root and prepares food,
and generates the oxygen that is essential for
life. If the scientists can prepare the model
of chlorophyll the problem of energy scarcity
can easily be solved.
Table-1: Technology that Needs to beCultivated Urgently
(Power Generation and Energy Conservation)
Sl. Source of Power RespondentsNo. and Technology (%)
for Conservation01 Solar Power 6802 Conservation Technologyon
Consumption side 5803 Wind Power 3904 Carbon Capture and Storage 3505 GeothermalEnergy 3206 Hydro-electric Power 1907 Wave Power 1208 TidalPower 0909 Pumped Storage
Hydroelectricity 0510 Other 11
11 No Response 02
In addition to this, according to theAsahiFoundation's survey observes "thoroughconservation technology on the consumptionside (electricity conservation, insulation, andenergy conservation) in daily life is necessary.This reflects the importance respondentsplaced not only on power generationtechnology itse lf but also on energyconservation among consumers. One must beaware of the need to prevent wasteful use ofenergy. Prodigal use of fossil fuel energycosts the nations heavily. In Odisha state thetheft and transmission loss is more than 30per cent. Energy saved is energy conserved.By this we can save the resources and reducethe environmental pollution.
'Nuclear Energy' was thought to be thebest alternative renewable source of energy.But after the Fukushima nuclear accidentpeople's perceptions in this regardhave changedand a large number of respondents across theworld oppose it (Table-2). Overall 67 per centof the citizens in the world oppose it, while inJapan 97 per cent of respondents oppose it.The survey indicated that overall 80 per centof respondents prefer some sort of review onnuclear policy. People understand that major
Table-2: More Citizens OpposeNuclearPowerSl. Country RespondentsNo. (%)01 Overall 6702 Japan 9703 United States & Canada 5804 China 3905 India 58
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nuclear accidents threaten health and lifethrough radioactive contamination and havenegative effects on the environment on aglobal scale. Radiation exposure risk rangesfrom change in blood chemistry up to deathwithin two hours depending on the dose.
Forests, Agricultural Lands and Wetlands
Forests, agricultural lands and wetlandshave tremendous potentiality to abateenvironmental hazards and therefore need tobe conserved at any cost for the present andfu ture genera tions . According to theInternational Union for the Conservation of
Nature (IUCN), 'Across the globe lie morethan a billion hectares of lost and degradedfores t land tha t could be res to red' .Deforestation accounts for up to 20 percentof the global greenhouse gas emissions thatcontribute to global warming, according to
World Bank. FAO data estimates that theworld's forests and forest soil store more thanone trillion tons of carbon-twice the amountfound in the atmosphere. Forests (bothterrestrial and coastal), and water bodies arethe store houses of biodiversity and act as the
biggest carbon sink. The local communitiesneed to be recognized as the custodians offorests and natural resources. They enjoy thebenefit of services rendered by such resources;and therefore have the moral obligation tosave forests, agricultural lands and wetlands in
order to guarantee inter-general equity. Byprotecting the natural forests and other habitatsthey play a vital role in reducing accumulation
of carbon dioxide and other green house gasesin the atmosphere.
For any development activity, howeverimportant may it be, the forests, agriculturallands or the wetlands need not be sacrificed ifit disrupts the ecological stability. Such areasare integral parts of global sustainabledevelopment and should be protected to theextent possible. The man-made forest is nosubstitute to natural forest as the former suffersfrom forest deficit syndrome. We now realisethat forests and wetlands are essential forsurvival of mankind like any other livingorganism. It is for this reason; there is globalconsensus towards protection, conservationand promotion of forest cover, agriculturallands and wetland areas. The enhancement ofsuch areas is possible through combinedefforts of the government agencies and thepeople at large. Forest and agriculture-relatedeconomic activities affect livelihoods of 1.6billion people worldwide; they provide socio-cultural benefits and are the foundation forindigenous knowledge; and as ecosystems.Forests play a critical role in mitigating theeffects of climate change and protectingbiodiversity. Similarly the wetlands also play acrucial role in maintaining the ecologicalbalance and the aquatic biodiversity.
Impediments to Address ingEnvironmental Problems
The results of the 21st Annual Survey oftheAsahi GlassFoundation conducted in 2012identified the following impediments to
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addressing environmental problems (Table-3).The table indicates that thehighest impedimentis 'Pursuit of Profit'. In decreasing order the
other impediments are mentioned in the table.
Table-3:Impediments to AddressingEnvironmental Problems
Sl. Impediment RespondentsNo. (%)01 Pursuit of Profit 82
(HumanDesire)02 Global Economic System 6103 Problems in Decision-
Making Systems 4804 Governance Problems 4705 Communication Problems 2406 LackofTechnicalResources 2107 Other 0608 No response 02
In a country like India where the accountabilityis not insisted upon, the progress of
development suffers more from these
impediments. A case in point is the slowprogress of development projects in Odisha
State under the Indian Union. Of the 86
Memorandumof Understanding(MOU) signedfor development of mineral based industries
(steel, aluminium, etc.), thermal power plants
and different other projects during the currentdecade, only 28 projects have either been
completed or just started; it is understood.
Therefore, the progress in this front has beliedexpectations as ` 23, 000 crores has been
invested so far as against the promised
investment of ` 4,11,726 crores. Most ofthese projects do not pick up the speed as
proposed because of problems like landacquisition, rehabilitation and resettlement of
the displaced persons, environmental
clearance, people's resistance, mine allocation,
bureaucratic delay, governance deficitsyndrome, etc. The project proponents engage
professional consultants for getting the
environmental clearance and such practicesdo not generally address to the local people's
socio-economic problems and environmental
pollution problems. Environment and socio-economic experts and scholars in the
universities, and conscious knowledgeable
citizens need to be engaged in such cases
appropriately address such issues.
Environmental Conditions of Concern
The world is now facing new challenges
of the environmental conditions of concern.
Those are climate change, loss of biodiversity,land use practices, environmental pollution,
food scarcity and contamination, energy
intensive modern life style, impact on socio-economic condition of urban and rural
populace, etc. (Table-4). The reversal of
environmental conditions to the prehistoric
ages is never possible. But if life is to sustainin its present form, still there is time and
opportunity. We must exercise restraint and
consume nature's resources less than itsregeneration in proportion. All human
activities must be environment friendly and if
need arises the development must be
compromised but not the environment.
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Table-4: Environmental Conditions of Concern
Sl. Category Main ElementsNo.
01 Climate Change Atmospheric concentration of carbon dioxide leading to globalwarming, oceanacidification, climatic aberrations (droughts, torrentialrainsandflooding, severe storms,heavysnow,abnormaltemperatures,drying of rivers and lakes, desertification, etc.).
02 Biodiversity Acceleration of species extinction as the effects of contamination,climate change, land use for non-forestry purposes.
03 Land Use Expansionofcultivated land for agriculture,overgrazing, diversionofnatural forests for development projects, urbanization, and land usewithout regard for the environment, etc..
04 Pollution/ Contamination River and ocean pollution-eutrophication caused by excessiveaccumulation of nitrogen and phosphorous, and contamination bychemical substances, atmospheric pollution, particulates suspendedin the atmosphere, soot and chemical substances.
05 Food Diminution of food supply from land and oceans.
06 Lifestyles Transformation of lifestyles from low energyconsumption to highenergyconsumption,fromnatural food to junk food, labour-intensiveto luxury- intensive, etc.
07 GlobalWarming Measures Progress ofmeasures for mitigation and adaptation. The Governmentof India and the state governments have prepared climate changeaction plans, but time willonly speak of its implementation.
08 Environment andEconomy Progress towards implementing an economic system to reflectenvironmentalcosts, the bearing of social costs, imposition of taxesfor fossil fuels that emit carbon dioxide whichcauses globalwarming-related damages, the realization of a green economy, sustainableeconomic development, etc.
09 Environment and Society Environmentalawarenessat the individualandsocietal levels,progressof environmentaleducation, poverty, the statusof women.
Conclusion
The CBD and the UNFCCCaddress green
house gas reduction, green energy production,
forest and wetland protection, biodiversity
conservation for sustainable development.
However, the basic need is to practise the
principles of simple life style that causes
minimum stress on nature's resources and
environment.
The 18th session of the Conference of
the Parties (COP) to the UNFCCC and the 8th
session of the COP serving as the Meeting of
the Parties to the Kyoto Protocol was held at
theQatar National Convention Centre in Doha,
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Qatar through 26th November to 8thDecember 2012. The conferences seek toaddress the threat of global warming causedby greenhouse gas emissions like carbondioxide. The concentration of carbon dioxidein Earth's atmosphere has reached 391 ppm(parts per million) as of October 2012 whilethe pre-industrial concentration was 280 ppm.The Doha Conference attendedbyabout 17,000participants made little progress towards thefunding of the Green Climate Fund. But itproduced a package of documents collectivelytitled The Doha Climate Gateway. Theconferenceoutcome is an eight year extensionof the Kyoto Protocol until 2020 limited inscope to only15% of the globalcarbon dioxideemissions due to the lack of participation ofCanada, Japan, Russia, Belarus, Ukraine, NewZealand and the United States and due to thefact that developing countries like China (theworld's largest emitter), India and Brazil arenot subject to any emissions reductions underthe Kyoto Protocol. The Kyoto Protocol-theworld's only legally binding agreement onemissions reductions finalized in 1997-wasset to expire at the end of December 2012, butthe confe rence ex tended the second
commitment period up to December 31, 2020.
Reference1. Results of the 21st Annual "Questionnaire on
Environmental problems and the Survival ofHumankind", The Asahi Glass Foundation, Japan,November 2012.
Working President, Orissa Environmental Society,
Plot No. ND/4, VIP Colony, Ekamra Vihar, Bhubaneswar-15Mob.-9437190420
PONDERING ON WATERON WORLDWATER DAY-2013
Manas Ranjan Senapati
Water is typically referred to as pollutedwhen it is impaired by anthropogeniccontaminants and either does not supporthuman use, such as drinking water, and/orundergoes a marked shift in its ability tosupport its constituent biotic communities,such as fish. Natural phenomena such asvolcanoes, algae blooms, storms, andearthquakes also causemajor changes in waterquality and the ecological status of water.
Water pollution is a major globalproblem. It has been suggested that it is theleading worldwide cause of deathsand diseasesand that it accounts for the deaths of morethan 14,000 people daily. An estimated 700million Indians have no access to a propertoilet, and 1,000 Indian children die ofdiarrheal sickness every day. Some 90% ofChina's cities suffer fromsome degree of waterpollution, and nearly 500 million people lackaccess to safe drinking water. In addition to theacute problemsof water pollution in developingcountries, industrialized countries continue tostruggle with pollution problems as well.
Causes of Pollution1. Pathogens2. Chemical & other contaminants
Sources1. Domestic Sewage:
It includes waste water from homes andcommercial establishments. Municipal anddomestic wastes are released into canals andrivers causing the pollution of major rivers ofour country.
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2. Industrial Effluents:
Water gets polluted by acids, alkalis,detergents, soaps, phenols, aldehydes, ketones,amines, cyanides, heavy metals, pesticides,insecticides, fungicides etc released fromseveral industries like sugar, paper, textile,steel, soap, oil refineries, fertilizers etc.
3. Agricultural Waste:
Pesticides, insecticides, fungicides,fertilizers etc enter waterways as runoff fromagricultural lands is reported to cause waterpollution.
4. Radioactive pollutants:
Radioactive pollutants enter into waterstreams due to nuclear tests, nuclear powerplants, atomic explosion etc.
Case Study I
Mo re tha n400 million peoplelive al on g th eGanges. Ane s t i m a t e d2,000,000 personsritually bathe dailyin the river, which isconsidered holyby Hindus.In the Hindu religion it is believed to flowfrom the lotus feet of Vishnu (for Vaisnavadevotees) or the hair of Shiva (for Saivites).The spiritual and religious significance couldbe compared to what the river Nile meant tothe ancient Egyptians. While the Ganges maybe considered holy, there are some problemsassociated with the ecology. It is filled withchemical wastes, sewage and even the remains
of human and animal corpses which carrymajor health risks by either direct bathing in
the water (e.g.: Bilharziasis infection), or bydrinking (the Fecal-oral route).
Case Study II
The industrial complex of Angul Talcherof Odisha has been identified as a criticallypolluted area in the Brahmani basin. Thewastewaters generated fromthe industries Viz,NALCO, TTPS, FCI, Orichem and miningoperations are primarily responsible fordeterioration of water quality of Mandira Riverwhich is a tributary stream of Brahmani river.
An international day to celebratefreshwater was recommended by UnitedNations Conference on Environment and
Development (UNCED) in Rio de Janeiro in1992. The United Nations General Assemblyresponded by designating 22 March 1993 asthe first World Water Day.UN-Water hasdedicated World Water Day 2013 (observedon 22nd March) to the theme Water
Cooperation. The objective of the day is tofocus international attention on the impact ofrapidurban populationgrowth, industrializationand uncertainties caused by climate change,conflicts and natural disasters on urban watersystems.It willencourage actionbygovernments,
organizations, communities, and individualsaroundthe world toactively engage inaddressingurbanwatermanagement challenges.
Department of Chemistry, Trident Academy of Technology
Bhubaneswar-751024, IndiaE Mail: [email protected]
Everyday activity in theGanges
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DROPS OF PRECIOUS LIQUIDKamalakanta Jena
1. Scarcity of Water in the Blue Planet
Earth is called the Blue Planet of our
solar system. Blue planet means a planet
covered withplenty of water. That's true. More
than 71% of the surface of Earth is covered
with water. Despite being a 'Blue Planet' we
face the shortage of water. The hydrosphere of
our planet consists of all bodies of water like
oceans, seas, lakes, rivers, streams, ground
water, glaciers, polar ice caps, atmospheric
moisture, precipitation etc. Of the whole
hydrosphere, more than 97% water is found in
the oceans and is too salty for human use.
Dissolved salts compose about 3.5 percent of
the water in the oceans, making it unfit for
drinking or agriculture. Out of the rest 3%
fresh water, two-third is stored untouched as
ice-caps found in the Polar Regions. The
remaining one-third fresh water is found in
rivers, lakes, groundwater and water vapour in
the atmosphere. Only 6 parts out of one
lakh parts (0.006%) of the total water is
actually available for our use. In other
words, if the whole available water of the
planet Earth could be accommodated in a
bucket, only a spoonful of water is our
share. That too, it is distributed unevenly
among agriculture, industry and domestic
purpose. Out of the spoonful of liquid,
agriculture consumes 70 %, industry 25 %
and rest 5 % water is used in domesticity.
In addition, this meagre amount is misused,
mismanaged and polluted.
2. Water is Life
Water is necessary for all living things.
Up to 90% of body weight comes from water
in some organisms. Water constitutes 40 to
75 percent of the body's weight apparently a
wide range due to individual fat content and its
percentage of overall weight. Our brain is
composed of 70% water. Our lungs are nearly
80% water and the same portion in case of
heart and kidney. Our muscle tissue contains
about 75% water by weight and skin70 percent.
Our bone has 22% water. About 83% of our
blood is water. The cell, which is known as
building block of our body, cannot live without
water. Thus, Water is our Life.
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Our body fat contains only 10 percent
water. Therefore, water amounts to a much
smaller percentage of total body weight in
grossly obese people. In general, body weight
of normal young adult males is 60 to 70
percentwater whilenormal youngadult females
are at 50 to 60 percent. On average, women
have a higher percentage of body fat than men.
style. Thus, water is precious in the living
Earth. In fact, the existence of hydrosphere in
the Earth has initiated life cycle in it.
Hydrosphere is an indispensable sphere for
the living organisms.
3. Uses of Water
Truly speaking, water is a synonym for
Life in biosphere. Water is necessary for
domestic, industrial, agricultural and various
other fields. Water is necessary in domestic
use for drinking, cooking, cleaning etc. It is
necessary in industrial use for cooling,
cleaning, processing etc. It is necessary for
plant growth and irrigation in agriculture.
Energy from hydro-electricity generation is
possible from water reservoir. Water is
necessary in ponds, seas or oceans for fisheries
and aquaculture. It is necessary in seas and
oceans for navigation and tidal energy. In
addition to common tidal energy, scientists
have decided to produce hydrogen from the
sea water in near future. It has an important
role in waste disposal through canals and
drainage. It is necessary for vital fields like
steamengine and nuclear power plants. Water-
ice is used in transportation of perishable
goods. The ocean serves main purposes in the
climate system.
The amount of water in the body must be
maintained within a fairly narrow range. We
get water from three main sources. Daily food
providesusabout 1,000mlwater, drink provides
Water has a great role in our life-style as
well. It helps digest our food, transport waste,
control body temperature and blood pressure.
It removes the dangerous toxins that are added
into our body. It cushions our body joints. It
acts as a transport for oxygen and nutrition
throughout the cells in the body. It encourages
bowel movement. It helps the normal kidney
function from getting impaired. It keeps us
from getting excessively dry skin. It is the
water that gives us life and regulates our life
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us about 1,200 ml and metabolism produces
another 350 ml. When food is metabolized the
main waste products are water and carbon
dioxide. On a regular cycle we lose about
1,500 ml water as urine, 100 ml water as
faeces, 600 ml water through the skin and
350 ml water through the lungs. When our
output of water is increased, our intake must
also increase to prevent dehydration. During
extreme exercise in a hot environment, intake
might have to exceed 15 liters a day to
maintain balance.
4. Contaminated Sources of Water
Water cannot be produced naturally. Its
availability is largely decided by climate,
geographical and physical conditions of a
locality. But demand of water is accelerated to
meet the needs of growing population and
industrial growth. Still we have least care for
conservation of the fresh water available to us
any time anywhere by any means. Rain is the
main source of water. In most of the countries
about80 % water available from rain is carried
off to the ocean and seas. On the other hand,
the ground water level is diminishing due to
uncontrolled use, deforestation and rapid
evaporation caused by globalwarming. Further,
the mere spoonful of water available to us is
graduallybecomingpolluted andcontaminated.
Surface water is the most common form
of water because we see it every day. It is the
water that travels or is stored on top of the
ground. This would be the water that flows
into rivers, lakes, streams, reservoirs, even the
oceans. Surface water is not safe. Runoff is a
problem because it carries waste materials
like vehicle oil, road silt and trash into the
water supply. Surface water needs various
treatments before it becomes drinking water.
This is done because things like leaves, fish,
animal droppings, boat fuel, industrial garbage,
chemicals, fertilizers, acid rain water and
various other toxic elements can easily get
into lakes, streams, and rivers.
Ground water is found under the ground.
We usually prefer ground water for drinking
purpose.A portion of surface water sinks into
the ground and becomes ground water. In the
water cycle, some of the precipitation sinks
into the ground and goes into watersheds,
aquifers and springs. Places that have lots of
sand underground will allow more water to
sink in than the ones that have lots of rock.
When the water seeps down, it will reach a
layer of ground that already has water in it.
That is the saturated zone. The highestpoint in
the saturated zone is called the water table.
The water table can rise and lower depending
on seasons and rainfall.
Groundwater flows through layers of sand,
clay, rock, and gravel. This cleans the water.
Becausegroundwater staysunderground, things
that fall into surface water can't fall into it.
This means that groundwater stays cleaner
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than water on the surface. But it is not always
safe. It has its problems too. When farmers
use fertilizers and insecticides, rain will wash
them into the soil where they get into aquifers.
Gasstations have big, underground tanks where
they keep the gas. If these leak, the gas sinks
into the groundwater, too.
5. War for Water
A wide range of water conflicts appear
throughout history. The United Nations
recognizes that water disputes result from
opposing interests of water users. These
conflicts occur over both freshwater and
saltwater and between international boundaries.
However, conflicts occur mostly over
freshwater; because freshwater resources are
limited. It is a vital, yet unevenly distributed
natural resource. International organizations
play the largest role in mediating water disputes
and improving water management. Yet water
conflicts go unresolved and become more
dangerous as water becomes scarcer with
increase of global population. Water is more
valuable than petroleum, as is evident from the
statement of World Bank Vice-President
Dr. Ismail Serageldin in a interview to
Newsweek during1995. Dr. Serageldin rightly
said, "Many of the wars this century were
about oil, but those of the next century will be
over water." We must think : What if the Third
World War is over water?
6. Save each Precious Drop
About four
bi ll ion peop le
from dif fe rent
na tions are
expected to be
seriously affected
by the scarcity of
fresh water by
2025. India will be
one of those
victimnations. The
shortage of fresh water will land the nations in
conflicts for water distribution. In our country
the conflict regarding the distribution of river
water has already started between different
states. But, we should remember that conflict
will not solve the problem. To survive on this
celestial abode, each and every nation should
care for that meagre water. We have no option
but to save each drop of precious water for our
offsprings and future generation.
Government Women's Junior College, Sundargarh, Odisha-770001
Mob - 9439501651, E-mail - [email protected]
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FIRE AND FIRE EXTINGUISHERSS.Acharya
In our day today life, we take the help offire mostly for making our own food. Whenman had no idea about fire, he used to eat rawfoods. Gradually he came to know the use offire and his living style changed accordingly.As the life advances, the risk of hazards alsoincreases. Scientifically fire is defined as therapid oxidation of the materials in theexothermic chemical process. Fire sometimesmay be very vigorous and can harm life. For afire to takes place, it needs a combustiblematerial, oxygen and heat. If any one of theseis notavailable, then the whole reaction processwill not take place. Fire can be classified into5 categories as given below [Table 1]
for each member present in the family. Most ofthe accidents are due to the faulty electricalwiring, overloading of the electricalcircuits, useof the heating equipments, cooking equipmentsandsmoking.Therearesome basicfirepreventiontips everyone should follow at home to reducethe fire hazards. These are cited below :
All electrical devices should be checkedand repaired at regular intervals.
The warm switches should be replaced.
Running the extension wires under thecarpet or door ways is very dangerous.Such practice should be avoided.
Overloading of the sockets should beavoided at all times. It is always advisableto put higher wattage appliances toindividual power outlet.
Th e cu rt ai ns , cl ot he s an d ot he rcombustible items should be kept awayfrom the electrical circuits as well asfrom the kitchen fire.
Children should never be allowed to playwith electrical appliances such as hairdriers, heaters or irons.
The electricalcircuitsmust bechildproof.
Always it should be a practice for all ofus to switch off the power outlets thatare not in use.
While repairing any electrical items,proper insulation should be maintained.
Smoke cancreate firedue toour ignorance.It is always advisable to check out thesmoke before going to bed.
It has been reported by the Natural fireprotection association that, nearly 85% of thefire deaths occurred at home due to fireaccidents in various modes. Thus firepreventionmeasureshouldbe the prime concern
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Heaters with automatic shutting offswitch can be used.
The space room heaters should not beused with extension cord.
The cooking appliances mustbeclean andwe must wipe away spills as they occur.
While cooking, it is advisable to wearshort sleeve cotton dresses.
The micro oven should have enoughbreathing space and freefrom obstruction.
Grease fire is caused by cooking oil orgreasy food. To control grease fire, thecooking pan has to be covered with a lidand the burner must be switched off tillthe fire has been put off clearly.
Water should not be used to put off thegrease fire. Water can cause splatter andhence spread the fire.
While going out, all the electricalappliances, along with the gas cylinder,should be properly checked andswitched off.
The gascylinders and other inflammablematerials should not be kept near theelectricalswitchboardsorany connections.
Like home, it is necessary to maintainfire safety at workplace. The following pointsshould be taken care of to have fire safety atthe work place.
The office should have emergency routeto exit.
Fire detection and warning system mustbe maintained in goodworkingcondition.
It is very important to remove or storesafely the inflamable & cooldownsubstances.
Special care to be taken to evacuateelderly, children and disabled persons incase of any emergency.
It is necessary to provide information tothe employees present in the workplaceabout the various provisions from thesafety.
All the staff members are to be trainedproperly to help each other at the time ofnecessity.
Fire Extinguishers
After taking the necessary measures tocontrol the fire hazards, it is also veryimportant to keep the fire extinguishers forthe emergency. Fire extinguisher is an activedevice to control fire in an emergencysituation. These are various types of fireextinguishers. Each type bears a specialgeometrical symbol to make it easier foridentification. The main function of theextinguishers is to reduce the Oxygen contentof the fire surroundings which lowers theignition temperature and stops the fire. Theyalso have some additional information. Theextinguisher chart is given below whichsignifies the categories. [Table 2]
It would be worthwhile to mention aboutthe invention and development of fireextinguishers.
The first fire extinguisher was inventedand tested by Ambrose Godfrey of England inthe year 1723. It cons is ted of fir e-extinguishing liquid containing a powderchamber of gun powder which was connected
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with a system of fuses which when ignited,explodinggunpowder and scattering solution.Then in the year 1818, George WilliamManbay used another type, a copper vessel of3 gallons capacity containing PotassiumCarbonate (PearlAsh) solution with compressair. Frankcois Carlier of France in 1866 useda solution of water and Sodium bi carbonatewith Tartaric acid as the extinguisher whichcould produce carbon dioxide. Later, AlmonM. Granger used Sodium Bicarbonate solutionand Sulfuric acid to expel pressurized water.The reaction between the two chemicalsresulted Carbon dioxide and pressurized waterthrough the nozzle of the cylinder to controlfire. In 1904, Aleksander Loran of Russiaused the chemical foam using burningnaphtha.The pyrene manufacturing company ofDelaware used Carbon tetrachloride as thefir e ex tingui sher. The liqu id carbontetrachloride vaporized and extingusushingflames by breaking the chain reaction of thefire process. Due to the toxic nature of the
chemical to the nervous system the use ofcarbontetrachloride hasbeen avoided. In 1940,Chlorobromomethane (CBM) was usedeffect ively as an extinguishing agenteffectively till 1969 as CBM is proved to beless toxic than the former chemical.
Then the carbon dioxide extinguisherwas used by Water Kiddle Company in theyear 1924 to reduce the fire in the telephoneswitch boards. Recently the dry chemicalssuch as Sodium Bicarbonates (purple-K),Ammonium Phosphate, Potassium chloride(Super-K) are used as the extinguishers. Inaddition to this, chemical [13% Al2(SO4)3and 8% NaHCO3] and mechanical foams [drywashing powder and H2O] have been used asextinguishers. In case of the fire in oilreservoirs, an aqueous film forming materialsynthetic foam) effectively reduces the fire.This substance has very low surface tensionwhich allows intense wetting property on thesurface of the oil, thus increasing the contactbetween the fire and oil surfaces.
By following the above mentionedprocedureanduse of the extinguishers at proper
time, we can effectively reduce the risk of firehazards toa large extent and ensure a safe living.
References:1. Encyclopedia of fire extinguishers
2. L. M. Desmukh, "Hazard indentification and RiskManagement Industrial safety Management" TMGpublication.
Department of Chemistry
KMBB College of Engineering and Technology,At/P.O.- Daleiput, Dist.-Khurda, Odisha-752056
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MEDIUM OF TELECOMMUNICATIONNikhilanand Panigrahy
G. K. Bhide,one-time researchscientist atBhabhaAtomic Researchcentre , has remarked:
"It seems as if one has turned round a fullcircle. The first telecommunication systemused a conductingcable. Then came 'wireless'communication. This communication wasestablished through space, by way of radiowaves as carriers, so that no cables wereneeded for carrying signal from one place tothe other. And , once again, we are back in theera of telecommunication using cables. Theonly difference is that the 'cable' is now madeof glass, a material that is non-conducting inthe conventional sense! The carrier waves arenow light waves with frequencies much higherthan the radio or microwaves". ('Fibre Optics',NBT Books, Page 62).
It will be interesting to make assessmentof this observation. For this we need to lookin to the his to ri ca l growth oftelecommunication. In this context, we mayrecollect the contributions of Robert Hooke(1635-1703), Charles Page (1812-1868), VonHelmholtz (1821-1894) and Philip Reis ofGermany (1834-1874) towards telephony(i.e., acoustic methods of communicationwhich are based on sound transmission, withthe help of electricity). Anyway the majorcredit for this goes to Alexander Graham Bell(1847-1922). The most remarkable date fortelephony was 10th March 1876, when Bell,confined to a room, sent a message to Watson,
staying in a nearby closed room with thewords, 'Mr. Watson, come here, I want you'.Immediately, on hearing these words, Watsonrushed out of his room and met with muchpleasure and astonishment, saying, 'Mr. Bell, Iheard every word you said distinctly'. Thustelephony ultimately bore fruit, to the great
delight of mankind.
Among other things, an importantcomponent that enabled the talk between Belland Watson to be a reality , is the currentcarrying wire, which may be otherwise calledas cable. When we focus our attention oncable, we should not forget telegraphy , whichpreceded telephony. Telegraph (meaning: towrite far) transmits messages optically andfirst came into existence when Samuel Morseopened the 37-mile public telegraph linebetween Baltimore and Washington D.C. on24 May 1844, the ceremonial first messagebeing 'What hath God wrought?" The messagewas sent, using Morse code, which consisted aseries of dots and dashes. In this system a cablewas used, which carried the electric pulses ofcurrent representing the message. Thus we findthat both for telegraphyandtelephony, the cableplayed a vital role, at the beginning.
Fig. 1 The twisted pair cable used in old telephony
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Anyway telephony as practised abovefaced problems like: switching. In 1921,automatic dialling system eased the problem.However the slow speed of functioning (in theorder of the thousandth of a second) of thetelephone circuit still persisted, as it wasel ct romechanical ly operated. But theintroduction of transistor removed thedrawback significantly as theswitching systemoperated very rapidly (in the order of millionthof a second). This led to the all-electronicswitching system, which had the additionaladvantage of being compact.
Still, long distance telephony continuedto pose a problem. In 1893, when Boston andChicago were connected by cable, thedesigners found that there is a practical limitof 1200 miles for cabling, as beyond thisdistance there was frequency distortion-thehigher frequencies being more weakened thanthe lower ones. Further the signal needed tobe amplified. In 1915, this was tackled byusing triode and this proved so effective thatonly three repeaters were needed to boost atelephone line, running across the UnitedStates, to the required strength.
During the enormous development ofcabling-system, several steps had been takenlike replacement of electromechanical onesby electronic telephone exchange and use ofcoaxial cables in place of 'Pair of Wires'. In
spite of these improvements, this system ofcommunication was found wanting to meetthe huge demand of the users. Thus entered
themicrowaveradiorelay systemwhich proveda good substitute for cable-system. Since itgenerates high-frequency radio waves, it cancarry telephone conversations. The firstmicrowave relay system operated betweenNewYorkand Boston in 1947. This has provednot only cost-effective in comparison withthe cable system but also transmitted telegraphmessages, television programs and computerdata. Later on, it led to global communicationnetworkvia communication satellitesas relays.For example, Telstar in 1962.
Radiotelephony is also called wirelessradio, as , without using cable, it could transmitspeech, music by radio waves, which aregenerated by high frequency alternatingcurrent. For replacing the cable, we use aradio transmitter which emits a continuouscarrier wave of a particular frequency. Thiscarries the sound waves, as pronounced by thespeaker (person), being converted into electricimpulses by a microphone, by the process ofmodulation. Then the receiver hears theoriginalsound at the other end, after it passes throughdevices which amplify, rectify and demodulate.
The story of telecommunication will notbe complete, unless it mentions the pioneeringwork of Prof. Jagadish Chandra Bose (1858-1937). He was the inventor of the World'sfirst solid-state diode detector of wirelesswaves, which was used by Marconi (1874-1937) for the first Trans-Atlantic Wirelesssignal in 1901. Even Bose had transmittedsignals over a distance of one mile (Ref: TheTimes and also Daily Chronicle, London).
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Use of microwaves, when used as carrierwaves,had a better bandwidth, their frequenciesbeinghigher than the conventional radio waves.With the help of geostationary satellites andthe technique of Frequency DivisionMul tiplex ing (FDM), wor ld -widetelecommunication became easier.
But it was felt that the frequencies ofthe carrier waves should be increased more ,so that it can be adequate to meet our pressingneeds. For this the infrared and visible lightwere chosen. But these frequencies can beutilised if we can channel or guide themwhich would of course obviously requiretransport fibre. Then only the intensity ofsignals would not die down over longdistances. Thus optical fibres and lasersources entered into the picture.
Optical fibresare made from 'high-purity,
low loss, low-dispersion glass used as mediumfor telecommunication by transmissionof highfrequency pulses of light. The basis ofoperation is the total internal reflection at theinterface between the higher refractive indexcore and the lower refractive index of the
sheath or cladding. Core is usually vitreoussilica doped with germania (Gio2)".
There are two types of optical fibre :
(i) Monomode fibre : It allows one mode of
light propagation and eliminates mode-
dispersion. (ii) Multimode fibre: It allows
large number of different modes in the
propagation of light.
Fibre-optics technology has assumed aprominent role in photonics, which is
otherwise called the 'application of photons
(light) in the transmission and processing ofinformation'. This type of technology has very
high speed of operation, is very accurate and
minimises the need for amplification of signalsduring passage. It is said that it can transmit
information at the rate of two billion bits per
second. For example, this is capable ofallowing more than five times the contents of
a 30-volume set of 'Encyclopaedia Americana'
over 50 kilometres in one second.
In fact , the medium of
telecommunication has started from cable
(metal wire) and has, at present, come to a
similar type of cable (optical fibre). But the
former was a conductor, whereas the later is an
insulator. This difference is not trivial. It
contains the richness of the scientific research
and technologicalinnovation inthe development
and forward journey of telecommunication.
And, hopefully, the cycle will go on.
Director (Retd.),Orissa State Bureau of Text Book Preparation & Publication
BadakhemundiBunglow, UtkalAshram Road, Berhampur- 760001Mob: 9437026651, e-mail: [email protected]
Fig. 2 Optical fibre used in the modern daytelecommunication
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BALANCEDDIET-NEEDFOR GOODHEALTHAND WELLBEING
Guru Prasad Mohanta
Our health and well being predominantlydepend on our eating habits and choice of
food. Nutrition is the science of food and howthe body uses it in health and disease. The
nutrients present in the food profoundlyinfluence our health. The body requiresproteins, fats, carbohydrates, vitamins,minerals andwater. Thefood not only provides
energy but all essential nutrients to grow andfunction properly. The common nutritionalproblems of public health in our country arelow birth weight, protein energy malnutrition
in children, chronic energy deficiency inadults, micronutrient malnutrition and diet
related communicable diseases. The coronaryartery diseases (illness related to heart), highblood pressure, type2 diabetes (non-insulinsensitive), certain cancers are related to diet
and nutrition. Consumption of food rich withfibre and antioxidants are associated withdecreased risk of certain cancers.
Nutrientsmay be divided into twogroups:
macronutrients comprising proteins, fats andcarbohydrates and micronutrients consistingof vitamins and minerals. Macronutrients arerequired in large quantities and micronutrients
are in small amounts. In the present article,sources and importance of proteins, fats andcarbohydrates are discussed. In separate
articles, vitamins andminerals wouldbecovered.
Proteins: The proteins are the functionalunitsof every livingcell. They forthe importantparts of the body's main structural components:muscles and bones. They are also the importantconstituents of blood, enzymes, hormones etc.Theyconstitutealmostone-fifth ofbody'sweightinadult. Theyare neededfor bodybuilding. Therequirements of proteins vary with age,physiological statusand stress.Pregnant womenand growing children require more proteins.
They are complex organic compoundscomposed of amino acids. Of the around 20amino acids required for our body, 9 are calledessential. These essential amino acids cannotbe synthesized by the body and are to besupported by diet. These include histidine,isoleucine, leucine, lysine, methionine,phenylalanine, theonine, tryptophan and valine.Other amino acids are synthesized by the body.
Animal source proteins like meat, fish,egg, poultry, milk, cheese and soy provide allessential amino acids and thus are consideredas complete proteins. The vegetable sourcesof proteins are pulses (legumes), cereals,beans, nuts, oil seed cakes etc. are also goodsources of proteins, but lack in few essentialamino acids. The combination of vegetableproteins allows eachvegetable protein to makeup for the amino acids missing in the otherprotein. One should consider total protein in-take inthe whole day rather than witheach meal.
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Carbohydrates: Carbohydrates are themain source of energy and provide about 4Kcal per gram. 70-80% of the total dietarycalories are obtained from carbohydratepresent in plant foods like cereals, millets,and pulses. The carbohydrates are divided intotwo types: simple carbohydrates and complexcarbohydrates. The carbohydrates with typeand sources are given in the table below:
Cellulose is indigestible (in human) butprovides dietary fibre. They move through thedigestive tract and out of the body. Insolublefibres absorb water in digestive tract; give thestool bulk and decrease it takes the stool tomove through the tract. Soluble fibres helpreducing cholesterol level, keeping blood sugarlevel low and reducing the riskof colon cancer.The carbohydrate reserve (glycogen) ofa humanadult is about 500 g and this reserve getsrapidly exhausted when a person is on fasting.
Fats (Lipids): The fats are the mostconcentrated sources of energy providingaround 9 calories per gram. They are themajor fuels for the body during rest and lightactivity. They are stored in our body in the
SimpleCarbohydrates
Examples Glucose,Fructose
Sucrose Lactose
Sources Fruits,Vegetables,
Honey
Sugar Milk
ComplexCarbohydrates
Examples Starch Glycogen Cellulose Gums andPectin
Sources Cereals,Millets,
Pulses, RootVegetables
Animalfoods
Vegetables,Whole grains
Vegetables,Fruits andCereals
form of usable energy. The fat beneath theskin help insulting us against cold. The fatssupport and cushion our heart, kidney andintestine. Fats in the diet help in absorption offat soluble vitamins.
Ghee, butter, milk, cheese, eggs, fats ofmeat and fish are the main source of animal fatwhile groundnut, mustard, sesame, coconutseeds provide thevegetable fats. Ghee, cookingoils (groundnut, soybean, sun flower, rice bran,safflower) are visible fats. Fats are present inthe diets but not visible to naked eye are non-visible fats. The sources for non-visible fatsare cereals, pulses, nuts, milk, and eggs etc.The major contributory source of fat to ourbody is the invisible fats.
Dietary fats contain both saturated andunsaturated fatty acids. Food containing largeamount of saturated fatty acids are usually
solid at room temperature and they belong toanimal fat. Foods containing large amounts ofmono-unsaturated and poly-unsaturated fattyacids are usually from plant sources and liquidat room temperature. However, the process ofunsaturated fatty acids (oils) converts the liquid
39ScienceHorizon
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oil to solid fat. The coconut and palm oil,though belong to vegetable source, have veryhigh content of saturated fatty acids. Fish oilscontain poly and mono-unsaturated fatty acids.
Saturated fatty acids are not considered ashealthy food. The combination of cookingoils is suggested to ensure recommended in-take of fatty acids. Poly-unsaturated fatty acidsare better as they reduce bad cholesterol.High intake of fats is associated with severalhealth conditions like obesity, coronary heartdiseases, cancer etc.
Food choice you make will significantlyinfluence your health both now andfuture. Thebalanced diet provides all the nutrients inrequired amounts and proper proportions.Ideally, it should provide around 50-60% oftotal calories from carbohydrates, about 10-
15% from proteins and 20-30% from fats.Here are few guidelines for you to follow: Eat variety of foods to ensure a balanced
diet. Eat plenty of vegetables and fruits. Eat
more high fibre foods. Ensure moderate use of edible oils and
animal foods and very less use of ghee,butter or vanaspati.
Avoid over eating to prevent overweightand obesity.
Eat less sugar. Restrict salt intake to minimum. Drinkplenty ofwater anddrink beverages
in moderation.
What you choose to eat have significanteffects on our health and well being. Develophealthy eating and encourage others too!
Food Groups Quantity ingram perportion
10-12 Years 13-15 Years 16-18 Years
Girls Boys Girls Boys Girls Boys
Cereals and Millets 30 8 10 11 14 11 15Pulses 30 2 2 2 2.5 2.5 3Milk (ml) and milkproducts
100 5 5 5 5 5 5
Roots and tubers 100 1 1 1 1.5 2 2Green leafyvegetables
100 1 1 1 1 1 1
Other vegetables 100 2 2 2 2 2 2Fruits 100 1 1 1 1 1 1Sugars 5 6 6 5 4 5 6Fat / Oil (Visible) 5 7 7 8 9 7 10
Professor, Department of Pharmacy,Annamalai University, P.O. Annamalai Nagar - 608 002, Tamil Nadu, INDIA,
Tel: 91-4144-239738(O), 238431(R), Cell: 91-9443885138, Fax: 91-4144-238080E. mail: [email protected] / [email protected]
Balanced Diet for Children and Adolescents:
40ScienceHorizon
MARCH, 2013
MIGRATION OF BIRDS-A LENGTHYJOURNEYBirat Raja Padhan
Migration is one of a very important and
spectacular events incase of birds life. Many
animals migrate but none to such distances
and with such regularity as the birds. Most
songbirds migrate at 500 to 2,000 meters, but
some fly as high as 6,800 meters; swans have
been recorded at 8,000 meters and Bar-headed
Geese at 9,000 meters.
A streamlined body shape and a
lightweight skeleton composed of hollow
bones minimize air resistance and reduce the
amount of energy necessary to become and
remain airborne. Well-developed pectoral
muscles, which are attached to a uniquely
avian structure called the furculum, power the
flapping motion of thewings. The long feathers
of the wings act as airfoils which help generate
the lift necessary for flight.
Birds have a large, four-chambered heart
which proportionately weighs 6 times more
than a human heart. This, combined with a
rapid heartbeat (the resting heart rate of a
small songbird is about 500 beats per minute;
that of a hummingbird is about 1,000 beats per
minute) satisfies the rigorous metabolic
demands of flight. Unlike mammalian or
reptilian lungs, the lungs of birds remain
inflated at all times, with the air sacs acting as
bellows to provide the lungs with a constant
supply of fresh air.
Bird Migration
Migration of animals movements of
animals in large numbers from one place to
another. In modern usage the term is usually
restricted to regular, periodic movements of
populations away from and back to their place
of origin.
The periodic seasonal movement of birds
from one geographic region to another,
typically coinciding with available food
supplies or breeding seasons. Birds may travel
hundreds or thousands of miles during
migration, depending on the species and the
areas they prefer for nesting habitat and
wintering grounds, and it may take several
weeks to make theentire journey. Some species
travel separately according to gender, usually
with male birds migrating earlier than females
in order to secure territories or begin nest-
building activities to attract mates. Migration
is a two way journey.It means a regular,
periodic,to and fro movement of a population
of birds.
41ScienceHorizon
MARCH, 2013
All species of birds do not take part in
the peageant of migration. Birds which remain
throughout the year in a country are known as
residents. There is a difference between
migratory bird and resident birds.
Kinds of Migration : Migration in birds takes
place in a variety of ways .Some areas follows-
1. Latitudinal Migration : The latitudinal
migration usually means the movement from
north to south, and vice versa. Most birds live
in the land masses of northern temperate and
sub arctic zones where they get facilities for
nesting and feeding during summer. The birds
return to the south for shelter during winter,
when north is covered with ice and snow.
Some trophical birds migrate during rainy
season to outer trophics to breed and return to
the central tropics in dry season. Many marine
birds also make considerable migration.
Several northAmerican & Eurasian birds
cross the equator to spend winter in deeper
and warmerparts of SouthAmerica andAfrica.
The American golden plover passes the nine
month of winter 8,000 miles south in the
pampasofArgentina, So enjoying two summers
each year & knows not a hint of winter.
2. Longitudinal migration : The birds
migrate from southern hemisphere to east-
west direction or from east to west & vice
versa is called as Longitudinal Migration.They
migrate from mountainous parts to plains
during summer and return to the mountains in
winter e.g., Patagonian Plover, Starling.
3. Altitudinal Migration : The altitudinal
migration occurs in mountainous region. Thebirds pass the summer in the mountainous
region. Many birds inhabiting the mountain
peaks migrate to low lands during winter. It ismerely a dispersal or short journey from the
bleaker slopes to the more protected valleys
& has been called as Vertical/AltitudinalMigration.
Eg-Golden Plover starts from Arctic
tundra and goes up to the plains of Argentina,
covering a distance of 11,250 km. Birds
migrate either in flocks or in pairs.
4. Partial Migration : Partial migration,
in which only some individuals of a species
migrate. Some birds do not migrate at all, by
an influx of new individuals of the same species
for a short period. Some species of birds seen
in an area throughout the year. Eg-Barn owls
(Tyto alba).
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MARCH, 2013
5. Irregular or Vagrant migration : A
bird is considered vagrant if it strays far outsideits expected breeding, wintering or migratingrange. The key term in defining vagrant is thedistance - a bird that is just barely outside itsnormal range is not usually considered vagrant,but a bird found hundreds of miles from itsfamiliar territory is a vagrant. Many times,vagrant birds may be from other continentsor so far from their expected range that theyhave never been seen in an area previously.E.g.-Herons
6. Seasonal migration : It is the regularseasonal journey undertaken by many speciesof birds.. Bird movements include those madein response to changes in food availability,habitat, or weather. Sometimes, journeys arenot termed "true migration" because they areirregular (nomadism, invasions, irruptions) orin only one direction (dispersal, movement ofyoung away from natal area). Migration ismarked by its annual seasonality. Eg. In BritainSwift, Swallows, Nightangles, Cuckoos etcare Summer Visitors. Fieldfare,Snow buntingare winter visitors. Snipes & Sandpipers arethe birds of passage, seen for a short timetwice a year.
Modes of flight during Migration
1. Nocturnal and diurnal flight : Somebirds may migrate at night or in the day.ie-Ducks,Gulls.Many larger birds fly mainlyby day. ie- Crows, Swallows, robins, hawksetc. They may stop to forage in suitable placesbut Swallows & Swifts capture their insect
food in the air as they travel. These diurnal
migrants have a greater tendency to travel inflocks. Some birds chiefly prefer to fly at
night, under the protective cover of darkness,to escape their enemies.
2. Segregation during migration : Somebirds travel in separate companies ie-Night
hawks, Swifts etc. But some travel in mixedcompanies of several species, due to similarity
in their size, method of search of food etc.E.g-Swallows, blue birds etc. In some speciesmale & female travel separately. Males arrive
first to build the nests. The young birdsgenerally accompany the females.
3. Range of Migration : The distances
travelledby migratory birds depend upon localconditions & the species concerned. Some
birds like the Himalayan snow partridgesdescend a few hundred feet only where asChicades come down nearly 8000 ft. Similarly
some birds travel thousand of miles. E.g.-Labrador travels a distance of 11000 miles.
4. Altitude of flight : Some birds fly very
close to the earth but generally most routinemigration takes place with in 3000 feet of theearth. Some small birds migrating at night fly
at 5000 to 14000 feet. Some species crossthe Andes and the Himalayas at altitude of20,000 feet or more.
5. Speed and duration of flight : Theaverage velocity of most small birds are around30 miles per hour.The greatest speed recorded
in India of species of Swift is 171-200 miles
43ScienceHorizon
MARCH, 2013
per hour (E.C.Stuart). Several hundreds of
miles may be covered non stop in a day ornight with an average of about500 miles.Birdsusually travel 5 to 6 hours a day. They take restin between for food or drink. The Golden
plover is the non stop bird travelling a distanceof 2400 miles.
6. Regularity of migration : Most of themigratory birds showing their regularity yearafter year in their timings of arrival &
departure. In spite of long distances travelledor change of weather they are such punctual astheir time of arrival is with in a day or two.
Most of the birds come to the same breedingplace year after year.
7. Routes of migration : Migratory birdsgenerally follow definite lines of flight.Nocturnal migration of small land birds
proceeds with the general airflow on a broadfront. In spring, it occurs northwards along
warm air currents from the south & in autumn,southward on the cool winds of the north.Deviation in path occurs due to configurationof land, coastline, courses of great rivers or
intervening mountain chains etc.
Factors affecting Migration
1. Visual landmarks : The sense of
direction has been attributed by topographicalfeatures or visual landmarks like great rivers,river valley, coastal lines, chains of oceanic
islands, mountain ranges etc. But a majority ofbirds migrating during night when they can noteasily make use of landmarks.
2. Experience : According to somenaturalists birds learn by experience. Some
older member benefiting by a tradition
Following a path in past several years
become leaders to guide the younger
generations. Birds certainly do not learn theirroute from elders as some of them donot fly
in flocks at all. Young birds make their first
journey independently, without the guidance
of the adult parents. They are evidently guidedby instinct impressed on their nervous system.
3. Telluric currents : The air currentswhich would lead the birds straight to their
destination must be very obliging and highly
ingenious.
4. Homing instinct : According to some
experiments hominginstinct enablingthe birdsto return to a goal as in the case of ants,bees
and carrier pigeons etc.
5. Earth's magnetic field - Some workershave given the idea that bird navigate through
responses to the earth's magnetic field and
their inner ear reacts to the mechanical corioliseffect produced by the rotation of the earth.
But there are no reliable evidences.
6. Celestial bodies :Accordingto Gustav's
experiment birds even possess an internal time
sense or time clock, with which they makenecessary adjustments in their course
according to their changes in their angles and
position of the sun as the day progressed. He
proved this by altering the direction of flight
44ScienceHorizon
MARCH, 2013
by using mirrors to give a false apparentdirection of the sun. The instinct has to beinherited because the young birds,that have
never migrat ed before , make simil arnavigational orientations to the sun whentravelling independent of their parents.
Advantages of Migration
1. Migration helps birds avoid harshclimatic extremes.
2. Migration from higher altitudes andlatitudes during winter affords protection fromcold and stormy weather, shorter days available
for searching food and scarcity of food.
3. The migrants get more food and better
shelter in their winter quarters in temperate ortropical regions than they would if they stayedat home.
4. During return in summer to the breedingareas in north once again provides suitable andunconquered nesting grounds, abundance offood with minimum efforts and long hours of
day light for searching food at a time whentheir population increases greatly.
In this way, birds migrate in order toutilize the food and to exploit for suitable
nesting purposes.
ReferenceKotpal, R.L-"Vertebrate zoology"www.wikipedia.com
Padhan,B.R-"Migration of birds"
Benkamura, P.O. - Pandari, Via - ITPS Banaharpali
Dist - [email protected]
QUIZTitaram NandaBrahmachari
1) Nervous system is responsible for
a) separation and removal of nitrogenous
metabolic waste matter from the body in
the form of aqueous solution.
b) the series of chemical changes which
release energy from the food material
c) transmission of character from one
generation to the successive generation
in the living being.
d) sending, receiving and processing nerve
impulse.
2) The major function of spinal cord is
a) conduiting for motor information
b) conductingsensory information a reverse
direction
c) coordinating certain reflex
d) all of these
3) The unit of nervous tissue is ?
a) Axon b) Dendrite
c) Myelin sheath d) Neuron
4) Which two hormones are responsible
for developingsensory andmotorneuron ?
a) ACTH (Adrenocorticotropic hormone)
and GABA (Gamma-aminobutyric acid)
b) Adrenaline and Epinephrine
c) LH (Luteinizing hormore) and MSH
(Melanocyte stimulating hormore)
d) BMP (Bone morphogenetic protein) and
SHH (Sonic hedgehog hormone)
45ScienceHorizon
MARCH, 2013
5. The master gland pituitary gland is
attached to the part of the brain ?
a) corpus callosumb) medulla oblongata
c) conus medularisd) hypothalamus
6. The nervous system consists ofa) the central nervous system (comprises
brain and spinal cord)b) the pe ripheral nervous sys tem
(composed of cranial)
c) the autonomic nervous system (made upof parasympathetic and sympathetic
nervous system)d) All of these
7. The nervous tissue develops from anembryonic
a) mesenchyme b) endodermc) mesoderm d) ectoderm
8. Brain is protected bya) skull b) scalp
c) sinus d) meninges
9. The Cerebrospinal fluid acts as
a) strong reducing agent
b) weak reducing agentc) oxidizing agent
d) shock absorber
10. Fore brain is included with ?
a) pons varoliib) corpora quadrigemina
c) cerebellum
d) cerebrum
11. Which of the following is well developed
in case of human ?
a) Neocortex (is functioning sensory
pe rcep tion , gene ra tion of motor
commands and conscious thought)
b) Pre fron ta l co rt ex (is impli ca ted
personality expressio decision making
and moderating social behaviour)
c) Temporal lobe (is involved in retention
of visual memory, processing sensory
input and storing new memory)
d) all of these
12. Human brain consists of pairs
of cranial nerves ?
a) 9 b) 10
c) 11 d) 12
13. A frog has 10 pairs of spinal nerve and a
man has pairs of spinal nerve ?
a) 37 b) 10
c) 11 d) 31
14. Which of the following has false nervous
system but not brain ?
a) Earthworm b) Cockroach
c) Amoeba d) Hydra
15. True nervous system firs t of all
originated in
a) Hirudinaria b) Ascaris
c) Hydra d) Taenia
16. The first cranial nerve is ?
a) Vagus b) Auditory
c) Abducens d) Olfactory
46ScienceHorizon
MARCH, 2013
17. Acetycholine is a hormone secreted by
nerve which aids in
a) diastole of the heart
b) blood clotting
c) systole of the heart
d) both a and c
18. Theflowoftears inwomanisstimulatedby
a) CNS
b) Peripheral nervous system
c) sympathetic nervous system
d) Parasympathetic nervous system
19. Themost common brain disorder is
caused due to high blood pressure, high
cholesterol in blood and heart disease ?
a) Cerebral palsy (CP)
b) Transient ischemic attack (TIA)
c) Alzheimer's disease (AD)
d) Cerebrovascular accident (CVA)
20. Which of the following technique has
been used for detecting brain wave
a) MRI (Magnetic resonance imaging)
b) CT (Computed tomography)
c) ECG (Electrocardiogram)
d) EEG (Electroencephalogram)
ANSWERS
1. (d) 2. (d) 3. (d) 4. (d)5. (d) 6. (d) 7. (d) 8. (d)9. (d) 10. (d) 11. (d) 12. (d)
13. (d) 14. (d) 15. (d) 16. (d)17. (d) 18. (d) 19. (d) 20. (d)
Department of Environmental Science,
Fakir Mohan University, Nuapadhi, Mitrapur, Balasore, OdishaMob. - 923899238, e-mail [email protected]
Q. What is sprain ?
Sprain means injury of the ligaments.
The ligaments have great tensilestrength. They
fasten the bones together at the joints. They
are composed of cells and fibres, but do not
stretch. They can only bend to permit the
joints to move. The strength of the joint is due
to the presence of ligaments around it.
Q. Who does sprain occur ?
When there occurs any injury to the
joint, one or more of its ligaments get stretched
or torn. While the joint is in an unfavourable
position, the weight of the body is abnormally
thrown on to it.Asa result, the joint is suddenly
twisted or wrenched. This sudden twist is
responsible for sudden stretching or at times
tearing of the concerned ligament(s). some
sprains are minor; others are associated with
5W'S + H :(Why, Who, What, When, Where and How)
SPRAINNityananda Swain
47ScienceHorizon
MARCH, 2013
extensivedamage to the adjacent tissues. Even
it maybe difficult to distinguish fromfractures.
Be very clear that a sprain is not the
same as fracture. In fracture, one or morebones are broken, but in sprains bones are
intact. However, it is, many a time, difficult to
differentiate a sprain from a fracture.Therefore, if there is an accident that involves
any joint, it is always advisable to get the
affected joint X'rayed. In X' Ray photograph,only the bones are visible, ligaments being
soft tissues, do not cast any shadow in the
X' Ray film.
Q. How does one diagnose the sprain ?
The sprain gives rise to severe pain.
There is swelling over the affected joint. The
skin over the joint may lookblack or blue. The
tenderness or pain is felt on touching or
pressing the joint at its bones, especially whenthe ligament is torn or stretched. On passively
stretching the affected joint, the ligament is
stretched ensuingexcruciating pain. In sprain,
there is no bony irregularity.
Q. Which are the joints that mostcommonly sprained ?
The most commonly sprained joints arethe ankle, the knee and the wrist.
The sprain in the ankle joint is verycommonly encountered on the street and athome. It is a common occurrence in athelets
too. In such injury, if of a serious type, a smallportion of bone to which the ligaments ortendors are attached, may also be broken waybesides stretching of the ligaments. If thefracture of the bone and the sprain areassociated, it is called a sprain-fracture.
The sprain of the knee is as common asthe sprain of the ankle. But the sprain of theknee is usually more incapacitating. Therefore,it takes a longer time to heal. If the spraininvolves displacement of any cartilage in theknee, surgical repair may be necessary.
The sprain of the wrist is usally sustainedwhen a person extends his arm and hand tocatch himself in falling or falling withoutstretched hands. These sprains are verypainful and inconvenient as they involve thehands. But such stra ins are not thatincapacitating as is the ankle sprain or theknee sprain.
48ScienceHorizon
MARCH, 2013
Q. What one has to do if one becomes a
victim of sprain ?
Although the sprain-injury appears to
be trivial, it should not be ignored. because
it limits movements at the affected joint andmay be associated with the fracture of bones,
a doctor, preferably an orthopaedician should
be consulted for correct diagnosis and
treatment.
However, before a doctor is consulted,
some first aid measures are to be undertaken
as are depicted below.
The procedures followed for the first aid
of sprain are popularly abbreviated as 'RICE'.
1. The letter 'R' stands for 'Rest' to thejoint. The patient should not be allowed to
walk if the ankle or the knee joint is invovled.
If the wrist joint is involved, he should be
discouraged to move that joint. The affected
wrist joint should be kept steady in a
comfortable position, especially in a sling.
2. The letter 'I' stands for 'Ice'. Ice-bagshould be applied at the affected joint to
reduce swelling, bruising and pain. If ice is not
available, cold water compress is applied. Theice-application may be continued for the nextone to three days. Two or three layers of cloth
need to be placed between the skin and theice-bag or the ice-cubes.
3. The letter 'C' represents 'Compression'.To help counteract swelling and provide somesupport, the joint is to be surrounded with a
thick layer of cotton wool and secured with abandage. Later, the injured joint is firmlysupported. The bandage should not be very
tight, or else it would interfere in circulationof the blood.
4. The letter 'E'is for 'Elevation'. Itmeans theinjured part should be kept in elevated position.If there issprain onthe wrist, the forearmand the
hand should be held elevated in a sling.
For a sprained knee or ankle, for the firstday or two the patient should be kept on bedwith the leg placed on pillows. This support
may be maintained at least for fifteen minutesout of each hour.
Once the tendency of swelling subsides,the joint may be immobilised with a firmer
support by an elastic bandage like a crepebandage. Besides, the application of ice can bereplaced by the use of hot fomentation. Theapplication of hot fomentation increases the
circulation of blood to the injured tissues and
hastens healing.
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