Pakistan Council of Scientific

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Pakistan Council of Scientific &Indutrial Research

01 Month Internship Report

By:

Sufian Abrar (Student of BE-IE)

Asad Mumtaz (Student of BE-IE)

From IIEE-PCSIR

[email protected]


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PREFACE

Over the summer of 2009, we were granted theunique opportunity to be employed by PCSIRLaborateries as an Internee. Under the supervisionof Electrical and Instrumentation department, wewere lucky enough to undertake 30 days internshipthat expanded my horizons and my way of

thinking.

The purpose of this report is to explain what we did and learned

during our internship period with the Pakistan Council of

Scientific & Industrial Research Environmental Program

(PCSIR) in the Division of Applied Physics. The report is also a

requirement for the partial fulfillment of Industrial Electronics

internship program. The report focuses primarily on the

assignments handled, working environment, successes and short

comings that the intern did encounter when handling various

tasks assigned to him by the supervisor.

Because the various parts of the report reflect the interns

shortcomings, successes, observations and comments, it would

be imperative that the recommendations are also given.

Therefore the report gives a number of comments andrecommendations on the internship programme.


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It is hoped that this report would serve as a

cardinal vehicle to the improvement of the

internship program.

Acknowledgement

The whole praise is to almighty Allah, creator ofthis universe. Who made us the super creaturewith great knowledge and who able me to

accomplish this work, we feel great pleasure inexpressing my deepest appreciation and heartiestgratitude to the staff of PCSIR-Karachi for theirguidance and great help during the internshipperiod.

We would like to express our deepest affection for

our parents and our friends who prayed for oursuccess and encouraged us during this internshipperiod.

A token of special thanks to the following peoplewho had been very friendly, co-operated with us

throughout our internship period in APPLIEDPHYSICS department and made it possible for us tolearn and gather information. These are the peoplewho in spite of their busy scheduling took time outto explain to us the procedures and mechanics ofwork in the organization.


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We would like to express my deepest thanks toMuhammad and Dr. Yaqoob, who really gave theirbest of time to us and we really learned a lot from

them in a very short period.

Introduction

Pakistan Council of Scientific and Industrial Research (PCSIR); was

established in 1953 under Societies Act to promote the cause of Science

and Technology in the country. Since 1973, it is functioning under the

Act of Parliament, which was amended in 1984. Chief Executive of the

Council is the Chairman who is appointed by the Federal Government.

The 21- member Council is the policy making body of the PCSIR, whichis composed of Chairman, three Members of the Governing Body, three

Directors of PCSIR Laboratories, four representatives from four

ministries, four Directors of Industries, one from each province and six

representatives of the industry.

The Governing Body is the executive organ of the Council and

comprises of the Chairman and three full-time members viz Member

(Science), Member (Technology) and

Member (Finance), nominated by the

Government.The Head Office of the PCSIRis functioning at Islamabad where offices of

the Chairman, Member (Science), Member

(Technology), Member (Finance) and

Secretary PCSIR are located. The Science

Wing is headed by Member (Science), who


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supervises matters relating to R&D, Training, International Affairs and

Scientific Information Services. The Technology Wing is headed by the

Member (Technology), who looks after the matters relating to

Technology, Industrial Liaison and Civil Works. The Finance Wing is

headed by the Member (Finance) who is in charge of activities inFinance and Audit and Accounts Divisions. The Chairman is assisted by

the Secretary and Administration and Establishment Wings, working

directly under him.

There are eleven Laboratories / Units and five HRD Centres established

throughout the country, headed by Director Generals / Directors who

directly report to the Chairman. In Head Office 150 officers / staff

including 07 Directors are working in different divisions / wings. There

are 681 Scientists / Engineers / Technologists working in differentLaboratories out of which 80 are Ph.D.s and others have M.Sc.

/MS/M.Phil. /B.E. degrees in multidisciplinary fields. These

are supported by 1656 technical and skilled staff and 178 administrative

staff.

Pakistan Council of Scientific and Industrial ResearchLaboratories Complex Karachi is a multifunctional unit.

The laboratory has highly educated, well trained and

skilled personnel, having expertise in different scientificfields with broad vision especially in Pharmaceutical,Marine, Food Sciences, Applied Chemistry, ChemicalEngineering, Physics, Computers, Instrumentation Designand Development etc.PCSIR Laboratories Complex, Karachi is a premier R & Dunit of PCSIR, which is committed to produce high qualityresearch / products by exploiting, indigenous natural

resources for the progress and development of thecountry.PCSIR Laboratories Complex, Karachi has the honors tobe the first multidisciplinary Unit in the whole Ministry ofScience and Technology to obtain the prestigiousinternational award of being certified to ISO 9001 for the


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quality of service, which it provides to industries amongorganizations of public and private sectors. RecentlyPCSIR Laboratories Complex, Karachi has beenaccreditated in ISO 17025 from Pakistan National

Accreditation Council (PNAC), MoST.


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ACTIVITIES

The broad-based activities of the PCSIRencompass almost the entire industrial sector

in the country; for the industrial units in operation have their ground-work in science andtechnology in which the PCSIR is both prominent and all too visible an organization on

the national plan. The PCSIR being the foremost industrial R & D organization is thelargest producer of indigenous technologies in an organized fashion. The R & D projects

of the PCSIR fall into two major categories:

Those that are sponsored or are user liked.

Those for which a user is likely to be available but has to be found out.

Evaluation of Locally Available Raw Materials

Pakistan is replete with respect to natural resources and their exploitation should havebeen the top priority in the process of industrialization of the country but instead of

using local materials, a consumer industry based on imported raw materials was largely

established.

PCSIR's main thrust in the starting years was to investigate the physico-chemical

composition of the locally available raw materials and to find out their possibleutilization. Out of the large number of research publications (over 4000) that PCSIR

produced during the period, 70 percent relates to the evaluation of local materials. Thedata thus generated is the single most important contribution of the PCSIR, which no

other organization in the country can claim. It is available in the form of researchpapers, technical bulletins, brochures and reports, etc. It covers the areas from minerals,

ores, clays, forest produced herbs, plants to marine and animal wastes. PCSIR canundertake survey and evaluation studies of raw materials and products on behalf of the

industry.

Process and Product Development

The Scientists and Technologists of PCSIR developed 684 industrial processes and

products and 350 numbers of patents, mostly based on the locally available rawmaterials. Out of these nearly 400 processes have commercially been exploited on

industrial scale. It has also executed around 50 Annual Development Programme (ADP)projects, which were mainly pilot plant studies, based on the data generated on the

laboratory level.

Investigative Analysis and Import substitution

A large number of formulated products are being imported at exorbitant rates resulting

in the expenditure of costly foreign exchange by the textile, leather, pharmaceutical,cosmetics, household chemicals, food additives and consumer products industries in the

form of emulsions, surfactants, resins, adhesives, plastic parts, perfumes, flavors andother chemical and non-chemical products. Most of these items are imported under

brand names. The expertise and technical manpower available in the PCSIR have beenable to decode and analyses over 2000 of these products and helped the local SME's in

the development of import-substituted materials.

Analytical and Testing Services

PCSIR is capable of undertaking large number of tests of raw materials and industrial

products and can provide physical, chemical, chromatographic and spectroscopic


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analytical services in the diversified fields.

It has the requisite highly qualified, trained and experienced resource manpower notavailable which is in any other organisation of the country.

It has the necessary infrastructure in terms of quality control, equipment and analytical

instruments and laboratories.

It has the capability to investigate, improve and introduce latest methodology of testing

and quality control in the production and application.

PCSIR at present is serving over 4000 SME's / clients all over the country annually in

quality control, analytical and testing area.

Quality Control Services to the Exporters

The major exports of Pakistan are textile, leather, food, sports and surgical goods and

products, which are based on locally available raw materials. The exports are essentiallymade to western European countries, America and Japan. These countries are becoming

more quality conscious and introducing various parameters and checks to monitor thequality of the imported products. ISO 9000, 14000 and 17025 etc standards are being

brought in to monitor the desired quality. Pakistan has faced much competition in theregion for exports and in order to remain competitive there is a need to educate, support

and provide technical and quality control services to the producers and exporters of

goods.

PCSIR is doing its best to extend these services to the exporters. Textile and leatherexportable items are examined for forbidden dyes, PCP, formaldehyde, heavy metals,

pesticides and fungicides and most of other undesirable chemicals on the request of theexporters and issuing analytical reports / certificates which are being accepted in Europe

and elsewhere. PCSIR has developed credibility for these test reports. Similarly fooditems being exported by Nestle and others are being tested for their microbial

contamination and shelf life. Exporters of surgical goods, and sports goods are alsogetting technical and analytical help from PCSIR. Under the supervision of EPB and

technical guidance of Mineral and Metallurgy Research Centre of PCSIR, a MaterialTesting Laboratory has been established at Sialkot to Cater to the needs of the exporters

of that area and PCSIR is imparting training to the technical staff posted in M T Labs

Sialkot.

Services to Government Departments and NGOs

Various Government departments such as Customs, Excise, Police, Administration,

Health and NGO's avail the analytical testing and advisory services of PCSIR in resolvingdisputes, fake and genuine products categorization investigative matters, narcotics,

screening of medicines for steroids, etc.

Help in Crisis Situations

Due to the availability of diverse expertise and extensive laboratory infrastructure,

PCSIR enjoy the status of focal point in the crisis situations and its scientific andtechnical staff is always ready to extend to the local Administration the technical help to

solve the problems and ameliorate the situation. The major areas where PCSIR has


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significant contributions are:

Trouble shooting problems of the industry

Fire accidents

Poisonous gases leakage

Explosions

Environment and Pollution Control

The expertise available in PCSIR in the field of Environment and Pollution Control is notonly training of its own S&T staff in the assessment, monitoring and control systems of

air, water and soil pollution but is also helping the local industry for self-monitoring and

impact assessments. It is also helping the Ministry of Environment, Local Governmentand Rural Development, Planning Division, Ministry of Industries in framing and

implementing National Environment Quality Standards (NEQS) of air, water, industrialliquid and solid effluents and gasses emissions. PCSIR is also assisting the local industry

in acquisition, modification of existing plants, handling of hazardous wastes, treatment ofeffluents, control of emissions, etc. for environmentally clean and safe productions.

PCSIR laboratories have already been recommended by the EPA as environmental

laboratories to carry out testing of environment samples. PCSIR scientists/technologistsare helping Ministry of Environment to prepare, organize and execute trainingprogrammes in the field of environment monitoring and assessment.

ISO - 9000/14000 Certification

On the introduction of the ISO-9000 series of the standards, the specified quality of theproducts has become a vital issue for all the companies of the country to conduct their

business according to the requirements of applicable standards.

In Pakistan PCSIR is the only organization, which is capable of doing quality

management work successfully as it has all desired facilities available within its premisesin each of the province of the country. PCSIR has over one hundred different types of

latest equipments and highly trained manpower to test and evaluate a factory's rawmaterials, in process inventories, finished products and the packed products which are to

be marketed. The manpower of PCSIR is also capable of doing the Environmental ImpactAssessment studies in and around the vicinity, a plant is operating.

The scientists of PCSIR are well aware of the ISO-9000, ISO-14000 and WTOrequirements which have introduced new world order for improving the quality of

products, services and management systems of the organizations. In this context, PCSIRplan to get ISO-9000 certification and accreditation against ISO-17025. In the very

recently under a joint project of MOST & M/O Commerce. Some 500 industries have

been examined by PCSIR scientists for the certification and about 250 industries haveadopted/received certification for ISO 9000 under the programme. An Incentive grants

of Rs. 200,000/- has also been provided to each successful client upon recommendactions of PCSIR.

Workshops, Seminars & Training Programmes

PCSIR arranges seminars, workshops and training porogrammes in the specialized fields

for the senior technical staff of the industry in order to update the knowledge ofindustrial workers and to teach the modern techniques, skills and latest methods for

improving the quality and standards of their industrial products. Some of the workshops


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and training courses held in PCSIR which were well attended and greatly appreciated bythe relevant industry included:

"Cathode Protection Techniques" for solving corrosion problems in the industry.

New Techniques in Metalography.

Technical training on ore beneficiation to the staff working at the Saindak copper ore

project.129 Technical Managers, Quality Control Managers, Calibration Managers receivedtraining in three batches in the sophisticated field of Metrology and Calibration.

Various training programmes were held in leather processing, leather finishing, andquality control for the employees of the leather industry.

Workshop on "Essential Oils, perfumes and Flavors" was held for the benefit ofCosmetics toiletries, flavors, perfumes household chemical manufactures.

Workshop on "food Preservation" was held for the food and beverage industry.

Training programme in "Cereal Technology and mycotoxins" for the RCD countries.

Workshop on "Oilseed Expelling Systems" for the Expeller manufacturers.

Seminar on "Synthetic Dyes and Intermediate Chemicals" for the local dye industry

Pre-Fesibility, Feasibility & Techno-Economic Studies

PCSIR has experienced and trained scientific and technical manpower to undertake these

studies on behalf of the industry. A number of technical reports and pre-feasibility

studies has been executed by PCSIR on the request of the local industry, Governmentagencies such as PUNJMIN, RDC, NDFC, SDA, BDA for survey, evaluation, upgrading of

raw materials required and projects based on the locally available raw materials.

Rural Support Technologies

PCSIR has developed a number of technologies for the uplift of the rural areas of the

country including:

Improved and modified village level sugarcane crusher developed under US AIDprogramme.

Modified Oil Seed Expeller developed under IDRC, Canada funded project.

Development of erucic acid and glucocinolate-free rapeseeds (crucifers) under PL-480project.

Bench Mark of Sugar Recovery from sugarcane for the farmers, project funded byMINFAL, Government of Pakistan.

Seed Decorticating Machine.

Nut Cracking Machine - hand operated as well as power operated for Agha Khan rural

support programme.

Potable water technology.

Carpet making machine.

Household disinfectants.

Preservation of vegetables and Fruits Technologies.

Major Fields Developed

The following are some of the major fields of R&D where necessary expertise, trained


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and experienced scientific and technical manpower and infrastructure of labs andequipment has been established which can cater to the needs of the local industry.

Applied Chemistry / Industrial Chemistry

Pharmaceutical and fine chemicals

Textile Dyes and Pigments

Textile, Sugar and Paper Chemicals

Polymers and Plastics

Cosmetics and Household Chemicals

From Plants and Herbs

Industrial Essential Oils

Oils, Fats, Soaps and Detergents

Leather Chemicals

Medicinal Water Conditioning

Pesticides and Insecticides

Inorganic and Industrial Chemicals

Phytochemicals

Narcotic Testing Kits

Medical Diagnostic Kits

Fillers for Rubber and Plastic Products

Petroleum Products

Biotechnology, Food Technology and Fermentation

Preservation of Food Materials especially through Dehydration of Vegetables andFruits

Synthetic beverage concentratesVinegar from molasses, apples, dates, etc.

Commercial food sauces

Bating agent for tanneries

Mushroom production.

Fortified breads

Meat and meat products.

Ice cream mixes.

Pickles, jams, jellies and sweets.

Baby foods, low calorie and high energy food supplements

Milk and milk productsFood additives and preservatives

Microbial enzymes

Animal and poultry formulated feeds

Soya bean meat and related products

Minerals and Metallurgy

Mineralogy and geochemistry


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Mineral processing / ore beneficiation.

Pyrometallurgy

Hydrometallurgy

Electrometallurgy

Physical metallurgy

Foundry technology

Corrosion and protection

Development of brighteners and electroplating chemicals

Heat treatment salt compositions

Evaluation of foundry sands moldings, silicates, bentonites and bonded sands

Graphite crucibles

Minerals based chemicals

Glass and Ceramics

Utilization of industrial mineralsDevelopment of all types of Alumino-silicate, magnesite, chrome, chrome-magnesite

and fire clay insulating refractories and evaluation of their raw materials.

Soda-lime silica glass products such as container glasses, signal glasses and dome

glasses.

Rapid hardening cements

Beneficiation of glass sands

Acid proof cement tiles and bricks

Frits and enamels including acid resistant

Low temperature and high temperature glazes for earthenware, stoneware and

porcelain

Pyrometric cones

Grinding wheals, rubbing bricks and horning sticks

High quality glass sands

Ceramic clays

High rupture capacity (HRC) fuses

Applied Biology & Marine Resources

Aflatoxins and mycotoxins in edible materials

Nematode-free nursery and nematicides from natural sources

Biofertilizers from marine sources

Fish culture technology

Biopesticides and insecticides

Preservation of fish, shrimps, etc.,

Marinated, fermented and spiced products from fish, shrimps and shellfish

Fish protein concentrate

Micro-nutrient frits


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Decorticating machine for oils seeds.

Rice bran utilization

Water conditioning for drinking.

Fruit drying and preservation

Standards and MetrologyMaintaining primary, secondary & working standards of based & derived quantitiesincluding linear, dimensional and angle measurements, surface measurements, mass,

volumes, density measurements, electricity, time, frequency, magnetism pyrometry,

temperature, pressure, hardness, refractive index, pH and conductivity measurements.

Calibration of industrial and laboratories equipments.

Engineering

Design and development of precision machines and machine tools, jigs, moulds, dies and

spare parts of high precision.

Production of components of satellites.

Machining, drilling, and sizing machine components on CNC machine. Designing and

fabrication of pilot plants, reaction vessels, shakers, vacuum dryers, filtration equipment,etc.


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TrainingWe received no formal training as such in terms of

our individual project. It was our responsibility tobecome familiar with the system and thedevelopment platform.

However, in this internship program, we learnedteam building exercises. Here we studied howdifferent types of people in the workplace

interacted. For example, we discovered firsthandhow our type (Creator-Innovator) clashed with theThuster-Organiser type and how to organize typesof people to build an effective and balanced team.

In the following session we are discussing whattype of process involved in our internship.


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Electrical Housewiring

Normally in Pakistan, there is mainly one condition

followed which provide about 220 volts alternatingcurrent(AC) in home faculty of about 50 hertz frequency

and the colour coding of hot and cold wires are red andblack. Red wire gives the way of phase and black wiregives neutral. We are advised not to connect cold wire to

switch because when hot wire connect direct to the loadtheres a cause of low power provide to the load when theswitch is off, for this reason we have to connect always

hot wire for switching purpose and cold wire directlyconnected to the load.Modern outlets have three different shaped holes toassure plugs can only be inserted in one way. Two of the

holes are considered grounds, for reasons of safety.

Proper grounding and the use of fuses are important tomaintain electrical safety in the home.

Home wiring

Typically, homes in Paksitan receive 220 volts of ACelectricity. Certain high-power devices, such as anelectric stove, use the full 220 volts. The rest of theoutlets in the house use 110 volts.

Wires into home

Usually, three copper wires come into the home. Two are

covered in black insulation and one has white insulation.Sometimes one wire is red instead of black. Each black or


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red wire is called a "hot" wire and has 110-volt AC. Thewhite wire is called the "common" and is grounded at thepower station.Measuring across the two hot wires results

in 220 volts. Measuring the voltage between a black (orred) and white wire, results in 110-volt AC.

Wiring configuration

Copper wire

Copper wire is used because it is a good conductor ofelectricity. Materials that do not conduct electricity as

good usually have a higher resistance. This results inwasted energy and the tendency to get hot, which couldbe a safety hazard.

In the 1960s many electrical contractors started to usealuminum wire instead of copper. Aluminum is almost asgood of a conductor as copper, but it is much less

expensive. After a number of years, it was found that thistype of wiring caused a potential fire hazard. Problemsdue to expansion caused overheating at connections


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between the wire and switches, outlets, or splices. Manyhomes had to be re-wired, although there still are manythat still have aluminum wiring but have never had

problems.

Wall outlets

The wall outlets usually have a one wide slot, one narrowslot and one round-with-flat-bottom hole. This is to

assure that each part of the plug will be used as it issupposed to and to increase safety. Older outlets haveboth slots the same size and no round hole.

Typical wall outlet

Outlet slots

The narrow slot is considered "hot" and is where the

alternating current power comes out. The wiring behindthe outlet to this slot is usually black in the Pakistan. The

wide slot is considered the "common" and is supposed tobe grounded. Using the white wire as a commongrounded wire, means that everyone is working from thesame zero voltage position.


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Round hole

The hole that is round on the top and flat on the bottomis an extra ground. Usually the wire behind the wall

outlet has green insulation. Sometimes it is a bare wire.This extra ground is to make sure your utensils are

properly grounded in the situation that someone hadimproperly wired the house. It is an extra safety

measure.

Common wire

Although the white wire is not supposed to be a "hot"wire, in some cases it is used that way, especially in older

homes that have the old style outlets. In general, this isacceptable, but it can result in problems. If you touch a

common wire that is properly grounded, you should not

get a shock. But if that wiring has made it hot, you canget a shock. Also, by using the white wire where theblack should be used, you may cause a short circuit.

Safety

Proper grounding and the use of fuses are important for

protection against shock, as well as to prevent electrical

overheating and fire hazards

Grounding

Correct grounding is very important. Often ground wires

are connected to water pipes that normally go into the


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ground. Connecting to a hot water pipe means that thewater heater is between the connection and the ground.The water heater may have plastic parts that would

insulate the connection to ground. Thus, using a hotwater pipe is not a good idea.

Another consideration in using water pipes to ground thecircuit is that plastic piping is often being used inplumbing. You must make sure there are no plastic pipesbetween your connection and the outside earth or

ground.

Fuses

Fuses and circuit breakers are used as a safety measurein case of short circuits. A fuse or circuit breaker will

break the connection if more current is passing throughthe wire than is considered safe. This will prevent thehouse wiring to overheat and start a fire.

Most homes now use circuit breakers instead of fuses.One reason is because people with bad wiring in theirhomes that constantly blow out fuses, would then force

pennies in the fuse receptacles, thus bypassing therequirement for a fuse. This removed the aggravation, as

well as the expense of buying new fuses, but it also oftenresulted in serious electrical fires in the house.

Summary

Most homes use both 220- and 110-volt AC electricity.Wires have black, red, white or green insulation,depending on their use. The holes in modern outlets

assure plugs can only be inserted in one way. Proper


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grounding and the use of fuses are important to maintainelectrical safety in the home.


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Contactor

In semiconductor testing, contactor can also refer to the specialised

socket that connects the device under test.

In process industries a contactor is a vessel where two streamsinteract, for example, air and liquid.

A contactor is an electrically controlled switch used for switching a

power circuit, similar to relayexcept with higher amperage

ratings. [1] A contactor is controlled by a circuit which has a much

lower power level than the switched circuit. Contactors come in

many forms with varying capacities and features. Unlike a circuit

breaker, a contactor is not intended to interrupt a short

circuit current.

Contactors range from those having a breaking current of several

amps and 24 V DC to thousands of amps and many kilovolts. The

physical size of contactors ranges from a device small enough to

pick up with one hand, to large devices approximately a meter

(yard) on a side.

Contactors are used to control electric

motors, lighting, heating, capacitorbanks, and other electrical

loads.
http://en.wikipedia.org/wiki/Device_under_testhttp://en.wikipedia.org/wiki/Relayhttp://en.wikipedia.org/wiki/Contactor#cite_note-0http://en.wikipedia.org/wiki/Circuit_breakerhttp://en.wikipedia.org/wiki/Circuit_breakerhttp://en.wikipedia.org/wiki/Short_circuithttp://en.wikipedia.org/wiki/Short_circuithttp://en.wikipedia.org/wiki/Electric_motorhttp://en.wikipedia.org/wiki/Electric_motorhttp://en.wikipedia.org/wiki/Electric_lightinghttp://en.wikipedia.org/wiki/Electric_heatinghttp://en.wikipedia.org/wiki/Capacitorhttp://en.wikipedia.org/wiki/Relayhttp://en.wikipedia.org/wiki/Contactor#cite_note-0http://en.wikipedia.org/wiki/Circuit_breakerhttp://en.wikipedia.org/wiki/Circuit_breakerhttp://en.wikipedia.org/wiki/Short_circuithttp://en.wikipedia.org/wiki/Short_circuithttp://en.wikipedia.org/wiki/Electric_motorhttp://en.wikipedia.org/wiki/Electric_motorhttp://en.wikipedia.org/wiki/Electric_lightinghttp://en.wikipedia.org/wiki/Electric_heatinghttp://en.wikipedia.org/wiki/Capacitorhttp://en.wikipedia.org/wiki/Device_under_test


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Construction

A contactor is composed of three different items. The contacts are the

current carrying part of the contactor. This includes power contacts,auxiliary contacts, and contact springs. The electromagnet provides the

driving force to close the contacts. The enclosure is a frame housing the

contact and the electromagnet. Enclosures are made of insulating materials

likeBakelite, Nylon 6, and thermosetting plastics to protect and insulate the

contacts and to provide some measure of protection against personnel

touching the contacts. Open-frame contactors may have a further

enclosure to protect against dust, oil, explosion hazards and weather.

High voltage contactors (greater than 1000 volts) may use vacuum or aninert gas around the contacts.

Magnetic blowouts use blowout coils to lengthen and move the electric arc.

These are especially useful in DC power circuits. AC arcs have periods of

low current, during which the arc can be extinguished with relative ease,

but DC arcs have continuous high current, so blowing them out requires the

arc to be stretched further than an AC arc of the same current. The

magnetic blowouts in the pictured Albright contactor (which is designed for

DC currents) more than double the current it can break, increasing it from

600 A to 1,500 A.

Sometimes an economizer circuit is also installed to reduce the power

required to keep a contactor closed; an auxiliary contact reduces coil

current after the contactor closes. A somewhat greater amount of power is

required to initially close a contactor than is required to keep it closed. Such

a circuit can save a substantial amount of power and allow the energized

coil to stay cooler. Economizer circuits are nearly always applied on direct-

current contactor coils and on large alternating current contactor coils.

A basic contactor will have a coil input (which may be driven by either an

AC or DC supply depending on the contactor design). The coil may be

energized at the same voltage as the motor, or may be separately

controlled with a lower coil voltage better suited to control byprogrammable

controllers and lower-voltage pilot devices. Certain contactors have series
http://en.wikipedia.org/wiki/Bakelitehttp://en.wikipedia.org/wiki/Nylon_6http://en.wikipedia.org/wiki/Thermosetting_plastichttp://en.wikipedia.org/wiki/Programmable_controllerhttp://en.wikipedia.org/wiki/Programmable_controllerhttp://en.wikipedia.org/wiki/Bakelitehttp://en.wikipedia.org/wiki/Nylon_6http://en.wikipedia.org/wiki/Thermosetting_plastichttp://en.wikipedia.org/wiki/Programmable_controllerhttp://en.wikipedia.org/wiki/Programmable_controller


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coils connected in the motor circuit; these are used, for example, for

automatic acceleration control, where the next stage of resistance is not cut

out until the motor current has dropped

Operating Principle

Unlike general-purpose relays, contactors are designed to be directly

connected to high-current load devices. Relays tend to be of lower capacity

and are usually designed for both normally closed and normally

open applications. Devices switching more than 15 amperes or in circuits

rated more than a few kilowatts are usually called contactors. Apart from

optional auxiliary low current contacts, contactors are almost exclusively

fitted with normally open contacts. Unlike relays, contactors are designed

with features to control and suppress the arc produced when interrupting

heavy motor currents.

When current passes through the electromagnet, a magnetic field is

produced; which attracts the moving core of the contactor. The

electromagnet coil draws more current initially, until

its inductance increases when the metal core enters the coil. The moving

contact is propelled by the moving core; the force developed by the

electromagnet holds the moving and fixed contacts together. When the

contactor coil is de-energized, gravity or a spring returns the electromagnet

core to its initial position and opens the contacts.

For contactors energized with alternating current, a small part of the core is

surrounded with a shading coil, which slightly delays the magnetic flux in

the core. The effect is to average out the alternating pull of the magnetic

field and so prevent the core from buzzing at twice line frequency.

Most motor control contactors at low voltages (600 volts and less) are air

break contactors; i.e., ordinary air surrounds the contacts and extinguishes

the arc when interrupting the circuit. Modern medium-voltage motor

controllers use vacuum contactors.

Motor controlled contactors can be fitted with short-circuit protection (fuses

or circuit breakers), disconnecting means, overload relays and an

enclosure to make a combination starter.
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Ratings

Contactors are rated by designed load current per contact (pole), maximumfault withstand current, duty cycle, voltage, and coil voltage. A general

purpose motor control contactor may be suitable for heavy starting duty on

large motors; so-called "definite purpose" contactors are carefully adapted

to such applications as air-conditioning compressor motor starting. North

American and European ratings for contactors follow different philosophies,

with North American general purpose machine tool contactors generally

emphasizing simplicity of application while definite purpose and European

rating philosophy emphasizes design for the intended life cycle of theapplication.

Current rating of the contactor depends on utilization category. For

example IEC Categories are described as:

AC1 - Non-inductive or slightly inductive rows

AC2 - Starting of slip-ring motors

AC3 - Starting of squirrel-cage motors and switching off only after the

motor is up to speed. (Make Locked Rotor Amps (LRA), Break Full

Load Amps (FLA))

AC4 - Starting of squirrel-cage motors with inching and plugging duty.

Rapid Start/Stop. (Make and Break LRA)

AC11 - Auxiliary (control) circuits

Applicaions

Lighting control

Contactors are often used to provide central control of large lighting

installations, such as an office building or retail building. To reduce power

consumption in the contactor coils, latching contactors are used, which

have two operating coils. One coil, momentarily energized, closes the


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power circuit contacts, which are then mechanically held closed; the

second coil opens the contacts.

Magnetic starter

A magnetic starter is a contactor designed to provide power toelectric motors. The magnetic starter has an overload relay,which will open the control voltage to the starter coil if it detectsan overload on a motor. Overload relays may rely on heatproduced by the motor current to operate a bimetal contact orrelease a contact held closed by a low-melting-point alloy. Theoverload relay opens a set of contacts that arewired in serieswith the supply to the contactor feeding the motor. Thecharacteristics of the heaters can be matched to the motor sothat the motor is protected against overload. Recently,microprocessor-controlled motor protection relays offer morecomprehensive protection of motors.

Perhaps the most common industrial use for contactors isthe control of electric motors.
http://en.wikipedia.org/wiki/Overloadhttp://en.wikipedia.org/wiki/Bimetalhttp://en.wikipedia.org/wiki/Wirehttp://en.wikipedia.org/wiki/Overloadhttp://en.wikipedia.org/wiki/Bimetalhttp://en.wikipedia.org/wiki/Wire


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Induction Motor

The AC induction motor is a rotating electric machine designed to

operate from a three-phase source of alternating voltage. Thestator is a classic three phase stator with the winding displacedby 120. The most common type of induction motor has a squirrelcage rotor in which aluminum conductors or bars are shortedtogether at both ends of the rotor by cast aluminum end rings.When three currents flow through the three symmetrically placedwindings, a sinusoidally distributed air gap flux generating therotor current is produced. The interaction of the sinusoidallydistributed air gap flux and induced rotor currents produces a

torque on the rotor. The mechanical angular velocity of the rotoris lower than the angular velocity of the flux wave by so calledslip velocity.In adjustable speed applications, AC motors are powered byinverters. The inverter converts DC power to AC power at therequired frequency and amplitude. The inverter consists of threehalf-bridge units where the upper and lower switch is controlledcomplimentarily. As the power device's turn-off time is longerthan its turn-on time, some dead-time must be inserted betweenthe turn-off of one transistor of the half-bridge and turn-on of it's

complementary device. The output voltage is mostly created by apulse width modulation (PWM) technique. The 3-phase voltagewaves are shifted 120 to each other and thus a 3-phase motorcan be supplied.

Methods of Starting Induction MotorAs we know, once a supply is connected to a three phaseinduction motor a rotating magnetic field will be set up in thestator, this will link and cut the rotor bars which in turn will induce

rotor currents and create a rotor field which will interact with thestator field and produce rotation. Of course this means that thethree phase induction motor is entirely capable of self starting.

The need for a starter therefore is not, conversely enough, toprovide starting but to reduce heavy starting currents and provideoverload and no-voltage protection.


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There are a number of different types of starter including TheDirect On-line Starter, The Star- Delta Starter, and Auto-

Transformer andRotor resistance.

Direct-on-Line Starter (DOL)The DOL starter switches the supply directly on to the contacts ofthe motor.As the starting current of an induction motor can be 6-8 times therunning current the DOL starter is typically only used for motorswith a rating of less than 5kW.

Star Delta starterThis is the most common form of starter used for three phaseinduction motors. It achieves an effective reduction of startingcurrent by initially connecting the stator windings in starconfiguration which effectively places any two phases in seriesacross the supply. Starting in star not only has the effect ofreducing the motors start current but also the starting torque.Once up to a particular running speed a double throw switchchanges the winding arrangements from star to delta whereuponfull running torque is achieved.Such an arrangement means that the ends of all stator windingsmust be brought to terminations outside the casing of the motor.

Auto-Transformer StartingThis method of starting reduces the start current by reducing thevoltage at start up. It can give lower start up currents than star-delta arrangements but with an associated loss of torque. It is notas commonly utilized as other starting methods but does have theadvantage that only three connection conductors are required

between starter and motor.

Rotor Resistance StarterIf it is necessary to start a three phase induction motor on loadthen a wound rotor machine will normally be selected. Such amachine allows an external resistance to be connected to therotor of the machine through slip rings and brushes. At start-up


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horsepower motors use squirrel- cage construction with toothed rotors.

When used with an adjustable frequency power supply, all motors in the

drive system can be controlled at exactly the same speed. The power

supply frequency determines motor operating speed.

Hysteresis motors are manufactured in sub-fractional horsepower ratings,

primarily as servomotors and timing motors. More expensive than the

reluctance type, hysteresis motors are used where precise constant speed

is required.

DC-excited motors made in sizes larger than 1 hp, these motors require

direct current supplied through slip rings for excitation. The direct current

can be supplied from a separate source or from a dc generator directly

connected to the motor shaft

Slip rings and brushes are used to conduct current to the rotor. The rotor

poles connect to each other and move at the same speed - hence the

name synchronous motor.

Synchronous motors fall under the category of synchronous machines

which also includes the alternator (synchronous generator). These

machines are commonly used in analog electric clocks, timers and other

devices where correct time is required.

The speed of a synchronous motor is determined by the following formula:

Where v is the speed of the rotor (in rpm), f is the frequency of the AC

supply (in Hz) and n is the number of magnetic poles.

Parts

A synchronous motor is composed of the following parts:

The stator is the outer shell of the motor, which carries the armaturewinding. This winding is spatially distributed for poly-phase AC

current. This armature creates a rotating magnetic field inside the

motor.
http://en.wikipedia.org/wiki/AC_motor#Hysteresis_synchronous_motorshttp://en.wikipedia.org/wiki/Revolutions_per_minutehttp://en.wikipedia.org/wiki/Utility_frequencyhttp://en.wikipedia.org/wiki/Utility_frequencyhttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/AC_motor#Hysteresis_synchronous_motorshttp://en.wikipedia.org/wiki/Revolutions_per_minutehttp://en.wikipedia.org/wiki/Utility_frequencyhttp://en.wikipedia.org/wiki/Utility_frequencyhttp://en.wikipedia.org/wiki/Hertz


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The rotor is the rotating portion of the motor. It carries field winding,

which may be supplied by a DC source. On excitation, this field

winding behaves as a permanent magnet.

The slip rings in the rotor, to supply the DC to the field winding, in the

case of DC excited types

Operation

The operation of a synchronous motor is simple to imagine. The armaturewinding, when excited by a poly-phase (usually 3-phase) winding, creates a

rotating magnetic field inside the motor. The field winding, which acts as a

permanent magnet, simply locks in with the rotating magnetic field and

rotates along with it. During operation, as the field locks in with the rotating

magnetic field, the motor is said to be in synchronization.

Once the motor is in operation, the speed of the motor is dependent only

on the supply frequency. When the motor load is increased beyond the

break down load, the motor falls out of synchronization i.e., the applied loadis large enough to pull out the field winding from following the rotating

magnetic field. The motor immediately stalls after it falls out of

synchronization.

Starting methods

Synchronous motors are not self-starting motors. This property is due to

the inertia of the rotor. When the power supply is switched on, the armature

winding and field windings are excited. Instantaneously, the armature

winding creates a rotating magnetic field, which revolves at the designatedmotor speed. The rotor, due to inertia, will not follow the revolving magnetic

field. In practice, the rotor should be rotated by some other means near to

the motor's synchronous speed to overcome the inertia. Once the rotor

nears the synchronous speed, the field winding is excited, and the motor

pulls into synchronization.


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supply grid run in lagging power factor, which increases reactive power

consumption in the grid, thus contributing to additional losses. In such

cases, a synchronous motor with no load is connected to the grid and is run

over-excited, so that the leading power factor created by synchronous

motor compensates the existing lagging power factor in the grid and theoverall power factor is brought close to 1 (unity power factor). If unity power

factor is maintained in a grid, reactive power losses diminish to zero,

increasing the efficiency of the grid. This operation of synchronous motor in

over-excited mode to correct the power factor is sometimes called

as Synchronous condenser.

Uses

Synchronous motors find applications in all industrial applicationswhere constant speed is necessary.

Improving the power factor as Synchronous condensers.

Electrical power plants almost always use synchronous generators

because it is important to keep the frequency constant at which the

generator is connected.

Low power applications include positioning machines, where high

precision is required, and robot actuators.

Mains synchronous motors are used for electric clocks.

Record player turntables

Advantages

Synchronous motors have the following advantages over non-synchronous

motors:

Speed is independent of the load, provided an adequate field current

is applied.

Accurate control in speed and position using open loop controls,

eg. Stepper motors.
http://en.wikipedia.org/wiki/Synchronous_condenserhttp://en.wikipedia.org/wiki/Synchronous_condenserhttp://en.wikipedia.org/wiki/Robothttp://en.wikipedia.org/wiki/Phonograph#Turntable_technologyhttp://en.wikipedia.org/wiki/Stepper_motorshttp://en.wikipedia.org/wiki/Synchronous_condenserhttp://en.wikipedia.org/wiki/Synchronous_condenserhttp://en.wikipedia.org/wiki/Robothttp://en.wikipedia.org/wiki/Phonograph#Turntable_technologyhttp://en.wikipedia.org/wiki/Stepper_motors


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They will hold their position when a DC current is applied to both the

stator and the rotor windings.

Theirpower factorcan be adjusted to unity by using a proper field

current relative to the load. Also, a "capacitive" power factor, (current

phase leads voltage phase), can be obtained by increasing thiscurrent slightly, which can help achieve a betterpower factor

correction for the whole installation.

Their construction allows for increased electrical efficiency when a

low speed is required (as in ball mills and similar apparatus).

They run either at the synchronous speed else no speed is there.

X-Ray Diffraction

In PCSIR, XRD is of Siemens brand and PCSIR have only

two Xrd machines in which one is functioning and other is

malfunctioned.

X-ray crystallography

X-ray crystallography is a method of determining the arrangement

ofatoms within a crystal, in which a beam ofX-rays strikes a crystal

and diffracts into many specific directions. From the angles and intensities

of these diffracted beams, a crystallographercan produce a three-

dimensional picture of the density ofelectrons within the crystal. From this

electron density, the mean positions of the atoms in the crystal can be

determined, as well as theirchemical bonds, theirdisorderand various

other information.

Since many materials can form crystals such

as salts, metals, minerals, semiconductors, as well as various inorganic,

organic and biological molecules X-ray crystallography has been

fundamental in the development of many scientific fields. In its first decades

of use, this method determined the size of atoms, the lengths and types of

chemical bonds, and the atomic-scale differences among various materials,

especially minerals and alloys. The method also revealed the structure and
http://en.wikipedia.org/wiki/Power_factorhttp://en.wikipedia.org/wiki/Power_factor_correctionhttp://en.wikipedia.org/wiki/Power_factor_correctionhttp://en.wikipedia.org/wiki/Ball_millhttp://en.wikipedia.org/wiki/Atomhttp://en.wikipedia.org/wiki/Crystalhttp://en.wikipedia.org/wiki/X-rayhttp://en.wikipedia.org/wiki/Diffractionhttp://en.wikipedia.org/wiki/Crystallographyhttp://en.wikipedia.org/wiki/Electronhttp://en.wikipedia.org/wiki/Chemical_bondhttp://en.wikipedia.org/wiki/Entropyhttp://en.wikipedia.org/wiki/Salt_(chemistry)http://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Mineralhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Alloyhttp://en.wikipedia.org/wiki/Power_factorhttp://en.wikipedia.org/wiki/Power_factor_correctionhttp://en.wikipedia.org/wiki/Power_factor_correctionhttp://en.wikipedia.org/wiki/Ball_millhttp://en.wikipedia.org/wiki/Atomhttp://en.wikipedia.org/wiki/Crystalhttp://en.wikipedia.org/wiki/X-rayhttp://en.wikipedia.org/wiki/Diffractionhttp://en.wikipedia.org/wiki/Crystallographyhttp://en.wikipedia.org/wiki/Electronhttp://en.wikipedia.org/wiki/Chemical_bondhttp://en.wikipedia.org/wiki/Entropyhttp://en.wikipedia.org/wiki/Salt_(chemistry)http://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Mineralhttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Alloy


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functioning of many biological molecules, including vitamins, drugs,

proteins and nucleic acids such as DNA. X-ray crystallography is still the

chief method for characterizing the atomic structure of new materials and in

discerning materials that appear similar by otherexperiments. X-ray crystal

structures can also account for unusual electronic orelastic properties of amaterial, shed light on chemical interactions and processes, or serve as the

basis fordesigning pharmaceuticals against diseases.

In an X-ray diffraction measurement, a crystal is mounted on

a goniometerand gradually rotated while being bombarded with X-rays,

producing a diffraction pattern of regularly spaced spots known

as reflections. The two-dimensional images taken at different rotations are

converted into a three-dimensional model of the density of electrons within

the crystal using the mathematical method ofFourier transforms, combinedwith chemical data known for the sample. Poor resolution (fuzziness) or

even errors may result if the crystals are too small, or not uniform enough

in their internal makeup.

X-ray crystallography is related to several other methods for determining

atomic structures. Similar diffraction patterns can be produced by scattering

electrons orneutrons, which are likewise interpreted as a Fourier

transform. If single crystals of sufficient size cannot be obtained, various

other X-ray methods can be applied to obtain less detailed information;such methods include fiber diffraction, powder diffraction andsmall-angle X-

ray scattering (SAXS). In all these methods, the scattering is elastic; the

scattered X-rays have the same wavelength as the incoming X-ray. By

contrast, inelasticX-ray scattering methods are useful in studying

excitations of the sample, rather than the distribution of its atoms.

Instructions for Siemens D5000 Diffraktometer (XRD)

Instrument

The software for computing data is the Siemens Diffrac AT

program V3.10. The X-ray tube has a lateral outlet window in the

D5000 diffraktometer. This X-ray tube with earthed anode is
http://en.wikipedia.org/wiki/DNAhttp://en.wikipedia.org/wiki/Experimenthttp://en.wikipedia.org/wiki/Crystal_structurehttp://en.wikipedia.org/wiki/Crystal_structurehttp://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Deformation_(engineering)#Elastic_deformationhttp://en.wikipedia.org/wiki/Drug_designhttp://en.wikipedia.org/wiki/Crystalhttp://en.wikipedia.org/wiki/Goniometerhttp://en.wikipedia.org/wiki/Fourier_transformhttp://en.wikipedia.org/wiki/Neutronhttp://en.wikipedia.org/wiki/Fiber_diffractionhttp://en.wikipedia.org/wiki/Powder_diffractionhttp://en.wikipedia.org/wiki/Small-angle_X-ray_scatteringhttp://en.wikipedia.org/wiki/Small-angle_X-ray_scatteringhttp://en.wikipedia.org/wiki/Elastic_scatteringhttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/DNAhttp://en.wikipedia.org/wiki/Experimenthttp://en.wikipedia.org/wiki/Crystal_structurehttp://en.wikipedia.org/wiki/Crystal_structurehttp://en.wikipedia.org/wiki/Electronicshttp://en.wikipedia.org/wiki/Deformation_(engineering)#Elastic_deformationhttp://en.wikipedia.org/wiki/Drug_designhttp://en.wikipedia.org/wiki/Crystalhttp://en.wikipedia.org/wiki/Goniometerhttp://en.wikipedia.org/wiki/Fourier_transformhttp://en.wikipedia.org/wiki/Neutronhttp://en.wikipedia.org/wiki/Fiber_diffractionhttp://en.wikipedia.org/wiki/Powder_diffractionhttp://en.wikipedia.org/wiki/Small-angle_X-ray_scatteringhttp://en.wikipedia.org/wiki/Small-angle_X-ray_scatteringhttp://en.wikipedia.org/wiki/Elastic_scatteringhttp://en.wikipedia.org/wiki/Wavelength


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supplied by a kristalloflex 710 X-ray generator which is installed in

console-type housing. An FK 60-04 air insulated X-ray diffraction

tube with Cu anode is suitable for the majority of the diffraction

examinations. The Siemens has a complicated energy dispersifive

(EDX), state of the class for certification. Students will be givenbeam time for mineralogy class.

2. Place prepared short microscope slide with clay treatment in

the 1-7/8 square holder and record the sample

identification. If you are using the thick 1-7/8 square glass

slides, record the sample identification.

3. Open XRD door and place slide onto round flexible stub, release

the stub lever and push the slide up until it is tight against the topof the three fixed feet.

4. Using the START, program either Siemens DIFFRACplus -

D5000 #1 (common) or XRD (common), then go toJob

Measurement. A table screen with information for the slide

to be run will appear with a menu bar across the top. The

DQL file can be edited within this section or under the

separate heading of XRD (common) or Siemens DIFFRACplus

- D5000 #1 (common) - Edit DQL. The DQL information

below is standard for most slides.

Scan distance 2o - 34o 2

Step size 0.02o (dont change this)

Step time 0.3 seconds

Scanning rate continuous*

Detector 1

Run time 8 mn 0 s (this will be

calculated from above scan

entries automatically)


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*continuous vs step scan - continuous takes 0.3 second to

scan to each 0.02o, where step moves 0.02o every 0.3

second (jumps from one 0.02o to the next).

5. Once the program is set there is not a reason to change unlessthe scan distance or step time can improve the pattern or

save beam time. Changes will decrease or increase the run

time for the pattern but could make the diffractogram not

contain an abundance of noise and messy patterns. Edit the

set-up if potassium slides are being run to read, 2o - 15o 2.

6. Type in information as needed for each of the headings. The

cursor will be at Raw File. At the prompt type A:\ no more

than 8 characters for file-name or D:\file-name for zip drive.Use file-names for samples that denote the treatment as well

as sample identification. Example: AF, MgSanta; AF,

MggSanta; AF, KSanta; AF, KHSanta. Move cursor to Sample

Identification. Type the same sample information that is

under Raw File. This will be the heading for your printed

diffractogram output later. Example: Mg-sat., Santa A

horizon. Click cursor to Parameter File, click on Browse,

find Anita and open that DQL file. If you want to edit this filefor scan distance or step time, go to the top menu under

Option, and then edit DQL-file. Click Execute Job, if

everything has been entered correctly. Check the input lines

below table entry box to make sure your file drive is correct

and the file-name is correctly spelled. Once the job is

executed DO NOT stop or abort the run --- the XRD will go

into cardiac arrest.

6. To watch the display for the sample running, go to START,

program Siemens DIFFRACplus D5000 #1 (common) or

XRD (common), Status Display and click there is the

sample pattern as it is running.


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7. To view pattern, go to, START,program Siemens DIFFRACplus - D5000 #1

(common) or XRD (common), then EVA. Select File and open raw XRD

file-name you want to view. If the toolbox is not visible on the screen, click

on the little hammer icon to get the toolbox. The tool box contains all the

options for changes in the patterns display. Click on Background and

replace. Click on Aberrant to remove the extraneous or erogenous peaks

present, then click replace. The option forSmoothing is not desirable for the

XRD diffractogram patterns because the appearance of the XRD will be lost.

The upper visual graph of XRD pattern should be checked closely to make

sure that all the peaks show. The cursor arrow can extend the line above the

peaks so they will be visible when printing. The peak search is under the

toolbox. The peaks can be marked and labeled, if needed.8. To print a hard copy of the XRD pattern, go to File, then page

& printer set-up. Landscape prints are better for the full

spectrum XRD. The usual set-up options are available for

printing. If title or other changes in actual XRD diffractogram

need to be made, then go to View, then Custom Style. The

screen box will allow for editing title, changing size, font, etc.

The tick marks for the X and Y can be edited or changed. Go

to Print Preview to view the XRD pattern before printing.

Step 7 and 8 can be done while the XRD is running.

Remember to keep the beam busy, so plan your computer

work to be efficient with sample running.

9. Remove the slide from the X-ray holder, place new slide in

holder, record identification, and follow operational steps as

outlined above.

10. A hard copy of the multiple patterns or sequences or

treatments on one page is useful for reports. A color print

can be made or a B/W print with labels for the individual

treatments in power point after the files have been importedinto Excel. The conversion of raw XRD files to the UXD

format will let the data file exchange of XRD files into Excel.

To convert the raw XRD files, go to, START, program

Siemens DIFFRACplus - D5000 #1 (common), then Data File

Exchange. Click on File, and then go to UXD format.


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Check the following properties for the conversion of data;

angle & intensity, angle & intensity, column 10 per line 1,

and check the box for skipping headers.

11. Go to File again, open and find the raw XRD file you want toconvert, open the file needed, click on the UXD icon on menu

bar to make the conversion of file, save file to same disk or

place the raw file is stored. If the raw file and UXD file are on

the same disk it will be easier to find and manipulate for

importing to Excel. It is not possible to convert the EVA files

with background, etc. subtracted to a UXD format. EVA

software does not support the transfer of their data to

another program. Of course, they want you to use their

software package; however, it is very difficult to do the

multiple patterns in EVA. The raw files will not have

background, etc. subtracted.

12. Open Excel and open the files from disk with stored UXD data.

Use fixed width and follow the next commands. Highlight the

columns of data, go to insert chart as a new sheet, select XY

scatter plot, and follow Excel steps for making a chart and adding

headings/titles, no grids. Highlight the line of the graph anddouble click, change line to 2 point size, black or color and no

points (marks). Excel graphs can be copied and transferred to

power point, stacked by making an axis and importing only the

graph lines that need to be stacked, changed to color or left black

and white and labeled with text draw for appropriate axis and

headings.


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Contributions to Chemistry and Material science

X-ray crystallography has led to a better understanding ofchemical

bonds and non-covalent interactions. The initial studies revealed the typical

radii of atoms, and confirmed many theoretical models of chemicalbonding, such as the tetrahedral bonding of carbon in the diamond

structure, the octahedral bonding of metals observed in ammonium

hexachloroplatinate (IV), and the resonance observed in the planar

carbonate group[ and in aromatic molecules. Kathleen Lonsdale's 1928

structure ofhexamethylbenzene established the hexagonal symmetry

ofbenzene and showed a clear difference in bond length between the

aliphatic CC bonds and aromatic CC bonds; this finding led to the idea

ofresonance between chemical bonds, which had profound consequences

for the development of chemistry. Her conclusions were anticipated

by William Henry Bragg, who published models of naphthalene and

anthracene in 1921 based on other molecules, an early form ofmolecular

replacement.

Also in the 1920s, Victor Moritz Goldschmidt and laterLinus

Pauling developed rules for eliminating chemically unlikely structures and

for determining the relative sizes of atoms. These rules led to the structure

ofbrookite (1928) and an understanding of the relative stability of

therutile, brookite and anatase forms oftitanium dioxide.

The distance between two bonded atoms is a sensitive measure of the

bond strength and its bond order; thus, X-ray crystallographic studies have

led to the discovery of even more exotic types of bonding in inorganic

chemistry, such as metal-metal double bonds, metal-metal quadruple

bonds, and three-center, two-electron bonds. X-ray crystallography or,

strictly speaking, an inelasticCompton scattering experiment has also

provided evidence for the partly covalent character ofhydrogen bonds. In

the field oforganometallic chemistry, the X-ray structureofferrocene initiated scientific studies ofsandwich compounds, while that

ofZeise's saltstimulated research into "back bonding" and metal-pi

complexes. Finally, X-ray crystallography had a pioneering role in the

development ofsupramolecular chemistry, particularly in clarifying the

structures of the crown ethers and the principles ofhost-guest chemistry.
http://en.wikipedia.org/wiki/Chemical_bondhttp://en.wikipedia.org/wiki/Chemical_bondhttp://en.wikipedia.org/wiki/Noncovalent_bondinghttp://en.wikipedia.org/wiki/X-ray_crystallography#cite_note-carb-28http://en.wikipedia.org/wiki/Kathleen_Lonsdalehttp://en.wikipedia.org/w/index.php?title=Hexamethylbenzene&action=edit&redlink=1http://en.wikipedia.org/wiki/Benzenehttp://en.wikipedia.org/wiki/Resonance_(chemistry)http://en.wikipedia.org/wiki/William_Henry_Bragghttp://en.wikipedia.org/wiki/Molecular_replacementhttp://en.wikipedia.org/wiki/Molecular_replacementhttp://en.wikipedia.org/wiki/Victor_Moritz_Goldschmidthttp://en.wikipedia.org/wiki/Linus_Paulinghttp://en.wikipedia.org/wiki/Linus_Paulinghttp://en.wikipedia.org/wiki/Brookitehttp://en.wikipedia.org/wiki/Rutilehttp://en.wikipedia.org/wiki/Brookitehttp://en.wikipedia.org/wiki/Anatasehttp://en.wikipedia.org/wiki/Titanium_dioxidehttp://en.wikipedia.org/wiki/Bond_orderhttp://en.wikipedia.org/wiki/Inorganic_chemistryhttp://en.wikipedia.org/wiki/Inorganic_chemistryhttp://en.wikipedia.org/wiki/Compton_scatteringhttp://en.wikipedia.org/wiki/Hydrogen_bondhttp://en.wikipedia.org/wiki/Organometallic_chemistryhttp://en.wikipedia.org/wiki/Ferrocenehttp://en.wikipedia.org/wiki/Sandwich_compoundshttp://en.wikipedia.org/wiki/Zeise's_salthttp://en.wikipedia.org/wiki/Supramolecular_chemistryhttp://en.wikipedia.org/wiki/Crown_etherhttp://en.wikipedia.org/wiki/Host-guest_chemistryhttp://en.wikipedia.org/wiki/Chemical_bondhttp://en.wikipedia.org/wiki/Chemical_bondhttp://en.wikipedia.org/wiki/Noncovalent_bondinghttp://en.wikipedia.org/wiki/X-ray_crystallography#cite_note-carb-28http://en.wikipedia.org/wiki/Kathleen_Lonsdalehttp://en.wikipedia.org/w/index.php?title=Hexamethylbenzene&action=edit&redlink=1http://en.wikipedia.org/wiki/Benzenehttp://en.wikipedia.org/wiki/Resonance_(chemistry)http://en.wikipedia.org/wiki/William_Henry_Bragghttp://en.wikipedia.org/wiki/Molecular_replacementhttp://en.wikipedia.org/wiki/Molecular_replacementhttp://en.wikipedia.org/wiki/Victor_Moritz_Goldschmidthttp://en.wikipedia.org/wiki/Linus_Paulinghttp://en.wikipedia.org/wiki/Linus_Paulinghttp://en.wikipedia.org/wiki/Brookitehttp://en.wikipedia.org/wiki/Rutilehttp://en.wikipedia.org/wiki/Brookitehttp://en.wikipedia.org/wiki/Anatasehttp://en.wikipedia.org/wiki/Titanium_dioxidehttp://en.wikipedia.org/wiki/Bond_orderhttp://en.wikipedia.org/wiki/Inorganic_chemistryhttp://en.wikipedia.org/wiki/Inorganic_chemistryhttp://en.wikipedia.org/wiki/Compton_scatteringhttp://en.wikipedia.org/wiki/Hydrogen_bondhttp://en.wikipedia.org/wiki/Organometallic_chemistryhttp://en.wikipedia.org/wiki/Ferrocenehttp://en.wikipedia.org/wiki/Sandwich_compoundshttp://en.wikipedia.org/wiki/Zeise's_salthttp://en.wikipedia.org/wiki/Supramolecular_chemistryhttp://en.wikipedia.org/wiki/Crown_etherhttp://en.wikipedia.org/wiki/Host-guest_chemistry


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In material sciences, many

complicated inorganic and organometallic systems have been analyzed

using single-crystal methods, such asfullerenes, metalloporphyrins, and

other complicated compounds. Single-crystal diffraction is also used in

the pharmaceutical industry, due to recent problems with polymorphs. Themajor factors affecting the quality of single-crystal structures are the

crystal's size and regularity;recrystallization is a commonly used technique

to improve these factors in small-molecule crystals. The Cambridge

Structural Databasecontains over 500,000 structures; over 99% of these

structures were determined by X-ray diffraction.

X-ray Diffractometer
http://en.wikipedia.org/wiki/Inorganichttp://en.wikipedia.org/wiki/Organometallichttp://en.wikipedia.org/wiki/Fullerenehttp://en.wikipedia.org/wiki/Porphyrinhttp://en.wikipedia.org/wiki/Pharmaceutical_industryhttp://en.wikipedia.org/wiki/Polymorphism_(materials_science)http://en.wikipedia.org/wiki/Recrystallization_(chemistry)http://en.wikipedia.org/wiki/Cambridge_Structural_Databasehttp://en.wikipedia.org/wiki/Cambridge_Structural_Databasehttp://en.wikipedia.org/wiki/Inorganichttp://en.wikipedia.org/wiki/Organometallichttp://en.wikipedia.org/wiki/Fullerenehttp://en.wikipedia.org/wiki/Porphyrinhttp://en.wikipedia.org/wiki/Pharmaceutical_industryhttp://en.wikipedia.org/wiki/Polymorphism_(materials_science)http://en.wikipedia.org/wiki/Recrystallization_(chemistry)http://en.wikipedia.org/wiki/Cambridge_Structural_Databasehttp://en.wikipedia.org/wiki/Cambridge_Structural_Database


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X-ray Fluorescence

In Pcsir, there is only one XRF of Bruker company (Siemens

brand) which is so expensive more important equipment for

testing composition.

X-ray fluorescence (XRF) is the emission of characteristic "secondary" (or

fluorescent) X-rays from a material that has been excited by bombarding

with high-energy X-rays orgamma rays. The phenomenon is widely used

forelemental analysis and chemical analysis, particularly in the investigation

ofmetals, glass, ceramics and building materials, and for research

ingeochemistry, forensic science and archaeology
http://en.wikipedia.org/wiki/X-rayshttp://en.wikipedia.org/wiki/Gamma_rayshttp://en.wikipedia.org/wiki/Elemental_analysishttp://en.wikipedia.org/wiki/Analytical_chemistryhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Glasshttp://en.wikipedia.org/wiki/Ceramichttp://en.wikipedia.org/wiki/Geochemistryhttp://en.wikipedia.org/wiki/Forensic_sciencehttp://en.wikipedia.org/wiki/Archaeologyhttp://en.wikipedia.org/wiki/X-rayshttp://en.wikipedia.org/wiki/Gamma_rayshttp://en.wikipedia.org/wiki/Elemental_analysishttp://en.wikipedia.org/wiki/Analytical_chemistryhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Glasshttp://en.wikipedia.org/wiki/Ceramichttp://en.wikipedia.org/wiki/Geochemistryhttp://en.wikipedia.org/wiki/Forensic_sciencehttp://en.wikipedia.org/wiki/Archaeology


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X-ray Fluorescence


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The physics of XRF

When materials are exposed to short-wavelength X-rays or to gamma rays,

ionisation of their component atoms may take place. Ionisation consists of

the ejection of one or more electrons from the atom, and may take place ifthe atom is exposed to radiation with the energygreater than its ionisation

potential. X-rays and gamma rays can be energetic enough to expel tightly

held electrons from the innerorbitals of the atom. The removal of an

electron in this way renders the electronic structure of the atom unstable,

and electrons in higher orbitals "fall" into the lower orbital to fill the hole left

behind. In falling, energy is released in the form of a photon, the energy of

which is equal to the energy difference of the two orbitals involved. Thus,

the material emits radiation, which has energy characteristic of the atoms

present. The term fluorescence is applied to phenomena in which the

absorption of radiation of a specific energy results in the re-emission of

radiation of a different energy (generally lower)

Physics of X-ray fluorescence; in a schematic representation

Characteristic radiation

Each element has electronic orbitals of characteristic energy. Following

removal of an inner electron by an energetic photon provided by a primary

radiation source, an electron from an outer shell drops into its place. Thereare a limited number of ways in which this can happen, as shown in figure

1. The main transitions are given names: an LK transition is traditionally

called K, an MK transition is called K, and an ML transition is called

L, and so on. Each of these transitions yields a fluorescent photon with a

characteristic energy equal to the difference in energy of the initial and final
http://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Atomhttp://en.wikipedia.org/wiki/Ionization_energyhttp://en.wikipedia.org/wiki/Ionization_energyhttp://en.wikipedia.org/wiki/Atomic_orbitalhttp://en.wikipedia.org/wiki/Electron_holehttp://en.wikipedia.org/wiki/Fluorescencehttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Atomhttp://en.wikipedia.org/wiki/Ionization_energyhttp://en.wikipedia.org/wiki/Ionization_energyhttp://en.wikipedia.org/wiki/Atomic_orbitalhttp://en.wikipedia.org/wiki/Electron_holehttp://en.wikipedia.org/wiki/Fluorescence


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orbital. The wavelength of this fluorescent radiation can be calculated

from Planck's Law:

The fluorescent radiation can be analysed either by sorting the energies ofthe photons (energy-dispersive analysis) or by separating the wavelengths

of the radiation (wavelength-dispersive analysis). Once sorted, the intensity

of each characteristic radiation is directly related to the amount of each

element in the material. This is the basis of a powerful technique

in analytical chemistry. Figure 2 shows the typical form of the sharp

fluorescent spectral lines obtained in the wavelength-dispersive method

(see Moseley's law).

Figure 1: Electronic transitions in a calcium atom. Remember,

when electrons are jumping down, one of the electrons in the

lower orbital is missing.

Primary radiation

In order to excite the atoms, a source of radiation is required, with sufficient

energy to expel tightly held inner electrons. Conventional X-ray

generators are most commonly used, because their output can readily be

"tuned" for the application, and because higher power can be deployed

relative to other techniques. However, gamma ray sources can be used

without the need for an elaborate power supply, allowing an easier use in

small portable instruments. When the energy source is asynchrotron or the
http://en.wikipedia.org/wiki/Planck_postulatehttp://en.wikipedia.org/wiki/Analytical_chemistryhttp://en.wikipedia.org/wiki/Moseley's_lawhttp://en.wikipedia.org/w/index.php?title=X-ray_generators&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=X-ray_generators&action=edit&redlink=1http://en.wikipedia.org/wiki/Synchrotronhttp://en.wikipedia.org/wiki/Planck_postulatehttp://en.wikipedia.org/wiki/Analytical_chemistryhttp://en.wikipedia.org/wiki/Moseley's_lawhttp://en.wikipedia.org/w/index.php?title=X-ray_generators&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=X-ray_generators&action=edit&redlink=1http://en.wikipedia.org/wiki/Synchrotron


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X-rays are focussed by an optic like a polycapillary, the X-ray beam can be

very small and very intense. As a result, atomic information on the sub-

micrometer scale can be obtained. X-ray generators in the range 2060 kV

in order to the K line, which allows excitation of a broad range of atoms.

The continuous spectrum consists of "bremsstrahlung" radiation: radiationproduced when high energy electrons passing through the tube are

progressively decelerated by the material of the tube anode (the "target"). A

typical tube output spectrum is shown in figure 3.

Figure 2: Typical energy dispersive XRF spectrum Figure 3: Spectrum of a rhodium target tube

operated at 60 kV,showing continuous spectrum and K lines

Dispersion
http://en.wikipedia.org/w/index.php?title=Polycapillary&action=edit&redlink=1http://en.wikipedia.org/wiki/Bremsstrahlunghttp://en.wikipedia.org/w/index.php?title=Polycapillary&action=edit&redlink=1http://en.wikipedia.org/wiki/Bremsstrahlung


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In energy dispersive analysis, the fluorescent X-rays emitted by the

material sample are directed into a solid-state detector which produces a

"continuous" distribution of pulses, the voltages of which are proportional to

the incoming photon energies. This signal is processed by a multichannel

analyser (MCA) which produces an accumulating digital spectrum that canbe processed to obtain analytical data. In wavelength dispersive analysis,

the fluorescent X-rays emitted by the material sample are directed into a

diffraction grating monochromator. The diffraction grating used is usually a

single crystal. By varying the angle of incidence and take-off on the crystal,

a single X-ray wavelength can be selected. The wavelength obtained is

given by the Bragg Equation:

Where dis the spacing of atomic layers parallel to the crystal surface.

Detection

In energy dispersive analysis, dispersion and detection are a single

operation, as already mentioned above. Proportional counters or various

types of solid state detectors (PIN diode, Si(Li), Ge(Li), Silicon Drift

DetectorSDD) are used. They all share the same detection principle: An

incoming X-ray photon ionises a large number of detector atoms with the

amount of charge produced being proportional to the energy of the

incoming photon. The charge is then collected and the process repeats

itself for the next photon. Detector speed is obviously critical, as all charge

carriers measured have to come from the same photon to measure the

photon energy correctly (peak length discrimination is used to eliminate

events that seem to have been produced by two X-ray photons arriving

almost simultaneously). The spectrum is then built up by dividing the

energy spectrum into discreet bins and counting the number of pulses

registered within each energy bin. EDXRF detector types vary in resolution,

speed and the means of cooling (a low number of free charge carriers iscritical in the solid state detectors): proportional counters with resolutions of

several hundred eV cover the low end of the performance spectrum,

followed by PIN diode detectors, while the Si(Li), Ge(Li) and Silicon Drift

Detectors (SDD) occupy the high end of the performance scale.
http://en.wikipedia.org/wiki/Bragg's_Lawhttp://en.wikipedia.org/wiki/Proportional_counterhttp://en.wikipedia.org/wiki/PIN_diodehttp://en.wikipedia.org/wiki/Silicon_Drift_Detectorhttp://en.wikipedia.org/wiki/Silicon_Drift_Detectorhttp://en.wikipedia.org/wiki/Photonhttp://en.wikipedia.org/wiki/Wavelength_dispersive_X-ray_spectroscopyhttp://en.wikipedia.org/wiki/PIN_diodehttp://en.wikipedia.org/wiki/Bragg's_Lawhttp://en.wikipedia.org/wiki/Proportional_counterhttp://en.wikipedia.org/wiki/PIN_diodehttp://en.wikipedia.org/wiki/Silicon_Drift_Detectorhttp://en.wikipedia.org/wiki/Silicon_Drift_Detectorhttp://en.wikipedia.org/wiki/Photonhttp://en.wikipedia.org/wiki/Wavelength_dispersive_X-ray_spectroscopyhttp://en.wikipedia.org/wiki/PIN_diode


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In wavelength dispersive analysis, the single-wavelength radiation

produced by the monochromator is passed into a photomultiplier, a

detector similar to a Geiger counter, which counts individual photons as

they pass through. The counter is a chamber containing a gas that is

ionised by X-ray photons. A central electrode is charged at (typically)+1700 V with respect to the conducting chamber walls, and each photon

triggers a pulse-like cascade of current across this field. The signal is

amplified and transformed into an accumulating digital count. These counts

are then processed to obtain analytical data.

X-ray intensity

The fluorescence process is inefficient, and the secondary radiation is

much weaker than the primary beam. Furthermore, the secondary radiation

from lighter elements is of relatively low energy (long wavelength) and has

low penetrating power, and is severely attenuated if the beam passes

through air for any distance. Because of this, for high-performance

analysis, the path from tube to sample to detector is maintained under high

vacuum (around 10 Pa residual pressure). This means in practice that most

of the working parts of the instrument have to be located in a large vacuum

chamber. The problems of maintaining moving parts in vacuo, and of

rapidly introducing and withdrawing the sample without losing vacuum,pose major challenges for the design of the instrument. For less demanding

applications, or when the sample is damaged by a vacuum (e.g. a volatile

sample), a helium-swept X-ray chamber can be substituted, with some loss

of low-Z (Z = atomic number) intensities.

XRF in chemical analysis

The use of a primary X-ray beam to excite fluorescent radiation from the

sample was first proposed by Glockerand Schreiberin 1928. Today, the

method is used as a non-destructive analytical technique, and as a process
http://en.wikipedia.org/wiki/Photomultiplierhttp://en.wikipedia.org/wiki/Geiger_counterhttp://en.wikipedia.org/wiki/Atomic_numberhttp://en.wikipedia.org/w/index.php?title=Richard_Glocker&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Hans-Wilhelm_Schreiber&action=edit&redlink=1http://en.wikipedia.org/wiki/Photomultiplierhttp://en.wikipedia.org/wiki/Geiger_counterhttp://en.wikipedia.org/wiki/Atomic_numberhttp://en.wikipedia.org/w/index.php?title=Richard_Glocker&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Hans-Wilhelm_Schreiber&action=edit&redlink=1


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control tool in many extractive and processing industries. In principle, the

lightest element that can be analysed is beryllium (Z = 4), but due to

instrumental limitations and low X-ray yields for the light elements, it is

often difficult to quantify elements lighter than sodium (Z = 11), unless

background corrections and very comprehensive interelement correctionsare made.

Energy dispersive spectrometry

In energy dispersivespectrometers (EDX or EDS), the detector allows the

determination of the energy of the photon when it is detected. Detectorshistorically have been based on silicon semiconductors, in the form of

lithium-drifted silicon crystals, or high-purity silicon wafers

Figure 4: Schematic arrangement of EDX spectrometer

Si (Li) detectors

These consist essentially of a 35 mm thick silicon junction type p-i-n diode

(same as PIN diode) with a bias of -1000 V across it. The lithium-drifted

centre part forms the non-conducting i-layer, where Li compensates the

residual acceptors which would otherwise make the layer p-type. When an

X-ray photon passes through, it causes a swarm of electron-hole pairs to

form, and this causes a voltage pulse. To obtain sufficiently low

conductivity, the detector must be maintained at low temperature, and

liquid-nitrogen must be used for the best resolution. With some loss of

resolution, the much more convenient Peltier cooling can be employed
http://en.wikipedia.org/wiki/Berylliumhttp://en.wikipedia.org/wiki/Sodiumhttp://en.wikipedia.org/wiki/Energy_dispersive_X-ray_spectroscopyhttp://en.wikipedia.org/wiki/Berylliumhttp://en.wikipedia.org/wiki/Sodiumhttp://en.wikipedia.org/wiki/Energy_dispersive_X-ray_spectroscopy


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change with time, so that continuous vigilance is required in order to obtain

chemical data of adequate precision.

Usage

EDX spectrometers are superior to WDX spectrometers in that they aresmaller, simpler in design and have fewer engineered parts. They can also

use miniature X-ray tubes or gamma sources. This makes them cheaper

and allows miniaturization and portability. This type of instrument is

commonly used for portable quality control screening applications, such as

testing toys for Lead (Pb) content, sorting scrap metals, and measuring the

lead content of residential paint. On the other hand, the low resolution and

problems with low count rate and long dead-time makes them inferior for

high-precision analysis. They are, however, very effective for high-speed,

multi-elemental analysis. Field Portable XRF analysers currently on themarket weigh less than 2 kg, and have limits of detection on the order of 2

parts per million of Lead (Pb) in pure sand.

Wavelength dispersive spectrometry

In wavelength dispersivespectrometers (WDX orWDS), the photons are

separated bydif

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Pakistan Council of Scientific