Student Research Journal - ASMS...International Science Fair 2012 INTERNATIONAL SIENE FAIR 2015 6 Abstract: Our project is about a motivational and interconnected to do list, Tick

South Australian Department for Education and Child Development trading as South Australian Government Schools, CRICOS Provider Number 00018A

ADELAIDE, SOUTH AUSTRALIA

Student Research Journal

Australian Science & Mathematics School

International Science Fair 2015


INTERNATIONAL SCIENCE FAIR 2015

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The Australian Science and Mathematics School conducts an International Science Fair (ISF) for invited students from partner schools on an annual basis. The students make an active contribution to the events of the science fair through presenting workshops and poster displays of aspects of the research work they undertake at their own schools.

A further key feature of ISF is the publication of formal written reports of the research works of the students.

We are pleased to present these research reports in this Student Research Journal of the International Science Fair 2015.

Glenys Thompson

Event Director

ASMS International Science Fair

11 September 2015

ISF 2015 Participating Schools

Australian Science and Mathematics School Australia

Camborne Science & International Academy England

Pembina Trails Schools Division Canada

Gwangju Science Academy for the Gifted South Korea

Hwa Chong Institution Singapore

John Monash Science School, Victoria Australia

Korea Science Academy / KAIST South Korea

Lycée Français de Port Vila Vanuatu

Lycee Lapérouse New Caledonia

Mahidol Wittayanusorn School Thailand

Middle School Associated with Shandong University China

NUS High School of Math & Science Singapore

Ritsumeikan Senior & Junior High School Japan

Australian Science and Mathematics School

Flinders University

Sturt Road

BEDFORD PARK SA 5042

Telephone: +61 8 8201 5686

Facsimile: +61 8 8201 5685

Email: [email protected]

Website: http://www.asms.sa.edu.au

South Australian Department for Education and

Child Development trading as South Australian

Government Schools, CRICOS Provider Number

00018A

mailto:[email protected]

http://www.asms.sa.edu.au/

International Science Fair 2012 International Science Fair 2012


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Table of Contents

Making A Real-time Monitoring System with Load Cells Page 4

By Jin-seob Lim, Seo-yeong Jeong,

Gwangju Science Academy for the Gifted, Korea

Tick It, A Motivational To-do List Page 6

By Gabriel Chu, Joshua Cheng, Richard Xiong,

Hwa Chong Institution

Investigation of the Salt Concentration of a Tea Tree Leaf with Height. Page 9

By Laurene Colin and Emily Qiao,

John Monash Science School

At What Height in a Tea Tree is the Salt Concentration in a Leaf the Highest? Page 12

By Tia Vella & Vidhi Patel


A Touch Screen; a solution for the future? Page 15

By Alexis Diringer, Emmanuel Godet,

Laperouse High School, New Caledonia

Spider’s Silk: a Future Material Page 17

By Maxime Jung-Dupoux, Rodrigue Pakoa, Jasmine Jolliot, Sixtine Lebeau,

Lycée Français de Port Vila

Study of Propagating Properties of Leaky Surface Wave on the Silicon Single Page 21

Crystal using Line Focused PVDf Transducer

By Sungjun Kim, Yoonho Noh, Mincheol Son, Dongjin Lee, YoungH Kim,

Korea Science Academy of KAIST

Jinan Aquatic Phytoplankton Investigation Page 24

By Shang Runyu, Shang Tianze, Han Runting, Fu Yixuan, Yang Chenglin, Sun Yuqiao

The Middle School Attached to Shandong University

Preparation of Composite Film Using Crystalline Cellulose Extracted from Rice Straw Page 25

By Chanida Jirapintu and Mataporn Limvoraphan

Mahidol Wittayanusorn School

A Test Kit for Determination of Formaldehyde in Solution of Food Page 28

By Chutikarn Sinlapasunthorn and Natthikul Thanteeraphap

Mahidol Wittayanusorn School, Thailand,

Germination and Growth of Salicornia Europaea in Singapore Page 30

By Brandon Lam, Heng Shi Ning

NUS High of Mathematics and Science

Exploring the Feasibility of using Thais Gradata as a Bioindicator for Heavy Metals Page 34

to Monitor Environmental Pollutants using Copper

By LIim Seok Hwan, Loh De Rong, Goh Yan Yih

NUS High School of Math and Science

Electrochemical Studies of 'Thermally Exfoliated Graphene Oxide-Carbon' Composite Page 37

in Varying Ratios as Potential Anode Material for Batteries

By Amos Sim, Keefe Wayne Teo, Luo Chen

NUS High School of Maths and Science



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Making A Real-time Monitoring System with Load Cells

By Jin-seob Lim, Seo-yeong Jeong

Supervisors: Gang-gil Lee, In-seok Jeong

Gwangju Science Academy for the Gifted, Korea

Abstract:

Many tragic accidents can be prevented if you can check the signs of danger. One good way is to monitor the

situation in real-time. The goal of this research is to make a real-time monitoring system using load cells in order to

prevent accidents. A load cell is a type of weight sensor that can be found in a digital weight scale. In this system,

multiple load cells are arranged in a row, connected to and controlled by arduinos. We made algorithms that calculate

the weight, speed, or moving direction of a car when it runs over the cells. For example, by measuring the moving

direction and weight of each object, we could monitor the total weight of a ship where the loads are constantly

incoming and outgoing. In this way, we can prevent the ship from being overloaded and make sure it is safe.

Introduction:

We often encounter big accidents on the news. In fact, many of them could be prevented. From these tragic

accidents, we learned that people are negligent of breaking the rules. One good way to stop the accidents from

happening is to monitor the situation in real-time. Starting from finding out whether a ship is overloaded, we tried to

create a safety-monitoring system using load cells.

Materials:

We used load cells and arduinos to create the real-time monitoring system.

A load cell is a type of weight sensor that can be found in a digital weight scale. When force is exerted on the load

cell, it becomes slightly deformed and its electrical resistance changes. The load cell can measure the exerted force

(load) by converting this change of resistance into electrical signal. The electrical signal, usually the value of voltage,

is proportionate to the force exerted.

Arduino is a type of microcontroller, or a small computer that can receive signals and process them. Arduinos are

programmable – we can control load cells by some programming. So we wrote

codes that perform safety monitoring.

Hx711 weight sensor module is placed between the load cell and the Arduino.

Method:

1. Production of the Hardware

The components of the system are connected like this: Load cell – Hx711 module –

Arduino – computer. We arranged multiple load cells in a row, so that an

object can pass over them in sequence. Three load cells are connected

to one Arduino. We added three LCD monitors to the Arduino to check

the current status in real time.

2. Programming with Arduinos.

When an object passes over the row of load cells, we apply the algorithm we have developed. The system measures

its weight, velocity, and the total weight of a ship according to its moving direction (into the ship/out of the ship).

This is how the total weight of a ship is calculated: the system records the time when an object passes over each

load cell. Comparing the time values, the system determines whether the load is coming in or going out. Because the

weight of the load is measured simultaneously, we can add the weight coming in, or subtract the weight going out

from the ship.

Velocity can be measured with this system, too. The distance between the load cells are known. By measuring the

delta t value of the moving load, velocity can be measured by the distance over delta t.



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Setting a limit to the velocity and the car weight, we can also clamp down on both overloading and speeding. We

tested these algorithms by running toy cars over the load cells.

Results:

1. Ship Total Weight Monitoring System

2. Traffic Counting and Velocity Measuring System

3. Overloading and Speeding Detector

Ship Total Weight Monitoring Speeding Detector Demo Overloading Detector Demo

Discussion and Conclusion:

We implemented the algorithms that calculate the velocity, weight, and total ship weight by the object that passes

over the array of load cells.

This project will be continued to expanding the load cell array into a two-dimensional one. We will observe the

arrangement of car axis in order to determine the type of the car.

Works Cited:

1. DFRobot Wiki - Weight Sensor Module V1 Sample Code. http://www.dfrobot.com/wiki/index.php/

Weight_Sensor_Module_V1

Works Consulted:

1. B. Vasuki, M. Umapathy, A. R. Senthilkumarr - Uncertainty Analysis of Strain Gage Circuits: Interval Method And

Interval Algorithm, International Journal On Smart Sensing and Intelligent Systems, vol. 2, no. 3.

2. Arduino - Liquid Crystal Library, Liquid Crystal Tutorial

https://www.arduino.cc/en/Reference/LiquidCrystal

https://www.arduino.cc/en/Tutorial/LiquidCrystal

3. Hackmeister.dk - 4 LCD displays on 1 Arduino

https://www.hackmeister.dk/2010/08/4-lcd-displays-on-1-arduino/



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Abstract:

Our project is about a motivational and interconnected to do list, Tick It, That allow our users to not miss out on important events or tasks. Groups can allow for to do lists to be shared among many users, which they can edit and create collaboratively. Motivational Experience Points are gained once a task is completed, and are deducted when you fail to meet a deadline. There will be a motivational point system in our app that awards one points for completing a task. And upon the completion of certain number of tasks and the accumulation of a certain number of points, one will be award badg-es. This will encourage students to complete as many tasks as possible and earn the badges. With this app, stu-dents will not have to worry about missing out on homework or assignments, as students can create a class group and have a to-do list for the whole class.

Introduction:

We have noticed that there are many students who do not complete their homework, leading to the dissatisfaction of teachers. Upon further investigation, we find out that this is, more often than not, a result of a lack of motivation or a lack of self-discipline, they do not feel a sense of accomplishment upon the completion of a task. These stu-dents are disorganised and unmotivated to complete their work. Hence, we decided to create an application for students, or anyone who requires group collaboration and planning. Our objective is to create an interconnected platform where students get to create and share their lists with others through a group function. There will also be a motivational point system in place. This will prevent procrastination, motive students to do work and enable them to see what they have missed out on.

Materials:

This mobile application is developed using the Eclipse Integrated Development Environment (IDE). We coded the app in Java. We used the Android Debugging Bridge to run our application and log any errors that may happen, as well as Photoshop and Illustrator to design our icons. For the data management, we used PHP to code our server-side webpages, as well as MySQL for online database storage, and SQLite for local database storage.

Method:

Firstly, we had to set up our login scripts and code, both on the server-side webpages and in the app itself. We basically created a MySQL database and PHP scripts for the input of data into our database. Then, we wrote scripts to allow users to sign in with Facebook or register with their emails. Next, we design the Graphical User Interface (GUI). We started on designing the app icons with differing resolu-tions for the various platforms our app is to be used on, we added in the backgrounds, the buttons and fonts to the app. Then, we added in the basic features of a to-do list app, allowing users to create their tasks, setting dead-lines, and deleting tasks. We proceeded to add in features such as the motivational point system, collaboration feature. Finally, we did a pilot and bug testing to further improve upon the app. As for the work allocation, Richard will be in charge of Java programming, PHP programming, designing of icons and XML programming. Gabriel will provide aid the creation of presentation slides and the written report. Joshua will be help in HTML coding and the web report.

Tick It, A Motivational To-do List

Authors: Gabriel Chu, Joshua Cheng, Richard Xiong

Supervisors: Mr Tan Choo Kee

Hwa Chong Institution



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Results:

‘Task it’ includes the following features:


We conducted surveys and pilot tests to find out if our app has met its objectives. We surveyed 54 students on

whether they felt the motivational system featured in our app has achieved its purpose.

84% of students said that the smiley face did motivate them to do better, and 78% said that the level system

encouraged them to finish their tasks on time, without procrastination.

Login page When one first opens our app, one is sees the login page. Here, one gets the choice of whether to login (with one click) using one’s Facebook account or to sign up for a new account with one’s email.

Home page One is presented with a motivational message, and a big emoti-con spurring one on. Today’s tasks are also featured so one know exactly what to do.

Task Management This page allow user to create and edit tasks by tapping the edit button. By pressing the done button, the task will be completed and gone from one’s list. The points will increase too. In our app, every done task adds 15 points, and every time one post-pone a task we minus 5 points. By accumulating points or completing tasks, one can also earn different badges.

Groups page Under this page one can see a list of all groups, with a counter of number of tasks in each one. One can create a group with the add group button at the top-right. After that, while creating a group, there is an auto-complete member chooser, allowing one to choose any member that is registered with Tick It, as long as he knows the member’s username or real name. Upon entering a group, one views a list of tasks. Finally, in the settings page, one can see one’s statistics, what badges there are, about the develop-ers, and one can also log out here.



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We also conducted a 1 week pilot test on a class of Secondary 1 students, and asked them on their opinions after

using the app. Most had positive opinions on our app, such as being more organised as they know exactly what

homework they need to do. This allows them to plan their time more efficiently. When asked on whether the app moti-

vated them, the students said that the level system had generally a positive effect on them. However, they suggested

that more tangible rewards like extra features and fun add-ons could be incorporated, instead of just badges. They

also suggested a comment system so students can discuss work directly on the app.

We did a comparison study of our app to existing to-do list apps. One would be ‘Todoist’, arguably the most popular to

-do list app across all platforms. It boasts an elegant design, impressive widgets, and customisable notifications. How-

ever, the collaboration features are only paid, and hence not used by many of the users. Another popular app is

‘Any.Do’. This app is popular because of its sleek and simple design, but the over-simplified interface may leave first-

time users disoriented, and confused about how to use the app. There is also a somewhat lack of classification in the

settings menu, and is rather haphazard. Lastly, we took a look at Wanderlist, which is available on many platforms like

Windows, Mac OS, Android, and iOS, this to-do list app allow users to create tasks and set reminders. The user inter-

face of this app is simple, and easy to understand. Wunderlist also allows users to contribute and share their tasks

with their friends. However, Wunderlist does not allow one to view necessary details like due dates to be viewed at a

glance.

One area for improvement would be the fact that our app may not be universally accessible as it is only available on

the Android platform. Thus, students with Apple phones or non-smartphones will not be able to access our app. This

may reduce the number of students using our app due to this lack of compatibility. Also, our app is susceptible to SQL

injection, which may threaten the security of our users’ data. It may also spell trouble if a hacker decides to drop our

tables.

Possible extensions for our project would include compatibility for Apple devices in order to cater to a wider audience.

This way, more students will be able to benefit from our app.

Another possible extension will be the addition of comments within the app. This way, students can discuss about

tasks right on the app. For example, students can ask questions if they do not know how to do a piece of homework,

and other students can answer.

Acknowledgements:

Any.DO and WWDC - Unrelated except for coolness. (n.d.). CoreCocoa. Retrieved July 28, 2014, from http:// core-

cocoa.wordpress.com/2012/06/13/any-do-and-wwdc-unrelated-except-for-coolness/

Announcing Todoist Next The To-do List for Life's Every Moment | Todoist Blog. (n.d.).blog Announcing

Todoist Next The Todo List for Lifes Every Moment Comments. Retrieved July 28, 2014, from https://todoist.com/

blog/2014/01/announcing-todoist-next-the-to-do-list-for-lifes-every-moment/

Aloha Startups. (n.d.). Todoist: The Ultimate Productivity Manager. Retrieved July 28, 2014, from http://

www.alohastartups.com/2013/08/28/todoist-the-ultimate-productivity-manager/

Apps I use (n.d.). . Retrieved July 28, 2014, from http://www.cdsmythe.com/apps-i-use/

Wunderlist 2.3.5. Date added: January, 6th 2014 - Freeware. (n.d.). Wunderlist 2.3.5 Download for Mac /

Screenshots / FileHorse.com. Retrieved July 28, 2014, from http://mac.filehorse.com/download- wunderlist/

screenshots/



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Investigation of the salt concentration of a tea tree leaf with height.

Authors: Laurene Colin and Emily Qiao

Supervisor: Mr Tan


Abstract:

A Dye Sensitised Solar Cell is a type of photovoltaic cell, commonly understood to have properties which takes

advantage of light and converting it to an electricity output. Since the major focus of scientists has been the

internal engineering, this experiment investigates how different environmental factors (Light Colour, Beam Width,

Light Intensity) will enhance the efficiency of the cell. Dye Sensitised Solar Cells are known to generate power

(current * voltage). Solar Cells are the future of sustainability because it is a renewable energy source that is

hoped to reduce the consumption of natural resources. It is expected to run the Earth’s electricity and power in the

future.

Introduction:

A Dye-Sensitised Solar Cell is a third generation photovoltaic (solar) cell and artificially mimics the natural light’s

absorption of energy in the first stage of photosynthesis. This is achieved as they work by relying on a sensitiser

(the dye that increases the rate of reaction) to catch photon particles which excites the electrons. The dye then

sends buzzing electrons into Titanium Dioxide which carries nano scale crystals that conducts away the electrons.

In the cell, a chemical electrolyte closes this circuit so that the electrons are trapped in the cell, creating an

electrical current. The movement of these electrons generates electrical energy.

Aim:

To investigate how different factors and conditions from the environment would affect the efficiency of Dye

Sensitised Solar Cells.

Materials:

*See separate document for the making of Dye Sensitised Solar Cell

Method:

Part A- Investigating the effect of changing the colour of light

Make sure the Dye Sensitised Solar Cell is in its constant light condition and position.

Tape a sheet of cellophane over the lamp’s output.

Place the Dye Sensitised Solar Cell under the light and measure the current and voltage using the multimeter.

Repeat steps 2 and 3 with the different coloured sheets of cellophane (red, green, blue) and also as a plain

light colour, each time testing the cells 3 times.

Part B-Investigating the effect of varying light Intensity

Make sure the Dye Sensitised Solar Cell is in its constant light condition and position.

Using the Amplifier, turn it on the lowest Volts level (for low intensity).

Measure the Dye Sensitised Solar Cell using the multimeter, both current and voltage.

Repeat process 3 and 4 twice per cell, increasing intensity level every time before measuring

Part C- Investigating the effect of varying the beam width

Colour of Light Light Intensity Light Beam Width

-Lamp -Multimeter

-Cellophane (Red, Green, Blue)

-Amplifier -Light Box

-Digital Lux Meter

- A4 Paper - Amplifier

-Light Box - Tape



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1. Using plain paper, construct 3 tubes size 3, 5 and 7cm in diameter and then tape the outside for strength and

to block the light.(Adjust the width of the beam of light by rolling up paper and recording the circumference of

the end, to act as a measured spotlight.)

2. Place the 3 cm tube 1cm inside the light box and taping any possible light escapes.

3. Measure the Dye Sensitised Solar Cell’s current and voltage on the multi meter.

4. Repeat steps 2, 3 and 4 with the different beam circumference sizes of 3, 5 and 7cm, recording the results as

you go.

Results:

Observations: The Dye Sensitised Solar Cells generated the most

power with a white light followed by red light, blue then green.

White light created the most Watts at 0.00073196 W whist red the

the most efficient on the light spectrum scale, with green the lowest

power recorded at 0.0001999W. The difference between the white

and red light is far greater than the red and green light’s power

generated.

Observation: The cells generated the most power with a beam width

of 5 cm. With a beam width of 3cm and 7cm, the cells generated the

least power.

All the pattern measured for the 4 cells follow the same path of

peaking at the 5cm width and then reducing as it increased. 5cm of

width reached 0.000485828W of power whilst the lowest of 3cm

produced 0.0000887W, a fair change for 2cm of additional width.

Observation: As the volts increases, so does the power. This graph

shows the average trend of the trials of Dye Sensitised Solar Cells.

This graph has a polynomial trend which shows the positive

fluctuations as the light intensity increases. For a 10Volts supply

difference, a large 0.0004383707W difference was obtained, as it

began as low as 0.0000010773W and reached 0.000439448W,

without being at its saturation point.



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LIGHT COLOUR- Observation of the Dye Sensitised Solar Cells demonstrated

that red light produced the most power followed by blue then green. The best

characteristics were understood after comparing it to the visual light spectrum.

The increasing wavelengths and decreasing frequency were shown to be the

most efficient but after conducting some research, it was understood that the

cells structure was also the reason for this. Blue light, which was hypothesised

to create the most power output, does not transfer absorbed energy efficiently

to the chlorophyll. On the other hand all of the red light is converted into

energy, thus being the most efficient in photosynthesising and solar cell

absorption.

LIGHT BEAM WIDTH- The results demonstrated that the peaking width was 5cm. The conclusion for this result is

based upon how light disperses. For example, a single ray in a theatre will not illuminate the room very much because

it reduces in intensity as it dissipates over space. However, that one beam of light is able to support an entire

bathroom as it is condensed and stored which allows it to be rebounded against the nearby walls. This demonstrates

how a Dye Sensitised Solar Cell reacts to different beam widths. Whilst 7cm allowed for too much light to pass by

without being absorbed by the cell, a 3cm diameter beam width did not cover the whole of the Dye Sensitised Solar

Cell. It was found that 5cm was the best width for light absorption.

LIGHT INTENSITY- This term refers to the amount of energy transmitted and is measured by the number of incident

photons per a certain period of time. By looking at the results, it is clear that the higher intensity of incident light on the

Dye Sensitised Solar Cell, the higher the power measured. 12 Volts of light allowed for more than 491.7 watts of

power to be generated by the Dye Sensitised Solar Cells, whilst 2 volts of light allowed for 0.47 watt of power to be

generated. This creates a factor that is able to be maximised for efficiency in the future. More sunlight or light density

means that higher amount of power is generated.

Finding a saturation point in the light intensity of Dye Sensitised Solar Cells would have been very interesting.

However, knowing that a change in intensity has a very large affect on the cells is very important. As for the light

beam width, being able to plot a few more width measurements could have been a further refinement to the

experiment process and data obtained.

The majority of the investigation reflected accuracy or reliability as it was controlled to ensure the light source, the

cells used and the conditions to be the same. Difficulties with controlling experimental set-up existed in the

experiment which varied the data collected very slightly. The main difficulty was the different distance between the

light source and the cell on different days which may have increased the voltage and current that the Dye Sensitised

Solar Cell generated. An independent variable was fully tested and collected over one session to reduce any effects

environmental fluctuation might have on the results.

Conclusion:

The aim, to investigate how different factors and conditions from the environment would effect the efficiency of Dye

Sensitised Solar Cells, was achieved as it was found that Light Colour, Beam Width and Light Intensity all affected the

amount of light that was absorbed by the cell. By increasing the intensity, finding the most power in the light beam

width of a 5cm and using a plain white light have shown to optimise the electricity generated. It would not be

beneficial to enlarge the area of the cell itself, but instead use these optimal environmental conditions to tile on facade

in large numbers.

Acknowledgements:

We would like to thank everyone who have been supporting us throughout this investigation journey. We thank our

teachers for their continuous support for us as this experiment would not have been possible without their help and

ideas.



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Abstract:

The purpose of the research was to discover the correlation between the salt concentrations in leaves at different

heights of a Tea Tree. The results revealed that there is a strong relationshipbetween the height of the leaves and the

salt concentration.The amount of salt present in the bottom of the tree was double the amount of the top.This research

may lead to studies into the filtration system of trees and their leaves which could point towards designing new

filtration systems.

Introduction:

Tea Trees are native to Australia and found along in coastal areas. Leptospermum laevigatum is the species used in

this study and it is native to south-east Queensland, along the coast to south-east South Australia and northern

Tasmania. They flower small 5 petal white flowers in the spring and early summer and can grow up to 5 metres

tall. Tea Trees are very hardy plants and can survive in most climates. As they are located near the coast, they make

good specimens to measure the salt levels of leaves at different heights because saline soil is very common in coastal

areas.

Salt is present in all soil and in the right amount provides vital nutrients to a plant. In coastal areas, the concentration

of salt in the soil is higher because of its location near the sea. The salt water is easily carried to soil by wind and rain.

The ground water along the coast also has a higher salinity so as the water table rises, more salt is brought into the

top soil, where plants collect their nutrients from. As the water evaporates from the soil, the concentrated salt is left

behind in the soil. In some cases salt can be seen as a white layer on top of the soil. Too much salt can stress plant

roots and cause it to release a stress hormone called Abscisic Acid, which affects the plants ability to perform

metabolic processes that are essential for its survival. Salt is transported through plants by the method of

transpiration. Transpiration is the process of evaporation of water and minerals from the leaves which draws the water

and minerals up through the plant. Transpiration allows water and minerals to be accessible to the whole plant. The

salt enters the plant from the roots; the epidermis, and is transported to the stele, then enters the xylem and spreads

throughout the rest of the plant.

Aim:

The aim of this experiment is to determine the relationship between salt concentration in leaves and their heights in

tea tree, by measuring the salt levels at different heights in leaves and soil of and near tea trees.

Hypothesis:

It is expected that concentration of salt in tea tree leaves will be the highest in the leaves collect from 0 to 1 metre and

there will be less salt present in the higher leaves than the soil.

Materials:

Lab Coat

Safety Glasses

Gloves

Tea Tree (Leptospermum laevigatum) leaves

Tape measure

24 zip lock bags

Deionised water

50ml measuring cylinder

Beaker

Sieve

At What Height in a Tea Tree is the Salt Concentration in a Leaf the Highest?

Authors: Tia Vella & Vidhi Patel


24 Volumetric flasks

Funnel

Hotplate

Tray

Oven

Scales

Atomic Absorption Spectroscopy, AAS

(sodium)



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Method:

Collect Specimens from two different locations (the specimens were collect at Ricketts Point and at Beaumaris

Sea Scouts). To collect the leaves, start picking from where the leaves start closest to the ground and collect

20 leaves from that height. Continue doing this at 50cm intervals up to 4m or as high as possible. When

collecting the soil samples, take them from 1m away from the tree and 10cm deep. Place each of the types of

samples in different zip lock bags. If possible collect soil and leaves closest to the ground and 4m from a third

site for extra comparison.

Lay out one set of leaves on the tray. Heat it in the oven. Take them out at regular intervals and weigh them. Once

the weight stops changing they are dry. Crush the leaves and then repeat for all the samples.

Once the samples are dry, measure out 0.2g of one of the samples into the beaker and crush them. Then

measure out 40ml of deionised water and add it to the beaker. Place on the hotplate for 20 minutes to boil.

After 20 minutes take the beaker off the hotplate and using the sieve and funnel pour the liquid into a

volumetric flask straining out the crushed leaves. Repeat for all the samples.

After all the leaves are boiled, pour one of the sample liquids into a measuring cylinder. Add deionised water until

there is 30ml of liquid in the measuring cylinder to dilute the samples.

Next, test the sodium level in the samples. First, run known sodium samples through the AAS to create a

calibration curve. Use the AAS to measure the level of sodium in each specimen. Measure the level of sodium

in the samples at least 3 times. The AAS does not need to be re-calibrated after each test.

Results:

Fig.1; Relationship between the height of the leaf and the approximate salt concentration.



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The results revealed that there is a strong relationship between the height of the leaves and the salt concentration.

The highest concentration was 20 and the lowest was 10. This is a difference of 50%, showing that the amount of salt

decreases the higher up the leaf is on a Tea Tree. After 3m the amount of salt present in the leaves decreases,

although around 1.5m, the concentration fluctuates. The results indicate that the trees do filter out salt as the higher

they grow and their leaves become more pure.

Next time, if the experiment was to be repeated, more of each sample would be collected to produce more accurate

results. Also collecting data from more than two different trees would ensure that the results were accurate, plus

gathering specimens from other inland areas would be beneficial to see if the correlation still occurs or if it is specific

to coastal areas. This study can now be further extended to other trees both native and non-native to Australia to see

if the results are specific to Australian native trees.

It has been determined that the amount of salt does decrease the higher up the leaf is found on a Tea Tree.

Acknowledgements:

Thank you to all the teachers that helped out with the research, especially Mr Thompson with giving his expertise with

the AAS machine. Also thank you to Paul Vella and Caterina Wiltshire for their help with collecting the samples and

assisting with the testing.

Works Cited:

SEB, Kate ‘How Plants Cope With Salinity’.Sebiology.org, 2015. Web 29 July 2015

Carnegie Institution. (2013, January 23). Breakthrough: How salt stops plant growth. ScienceDaily. Retrieved July 29,

2015 from www.sciencedaily.com/releases/2013/01/130123133709.htm

Anpsa.org. au ‘Leptospermum Laevigatum’.2015, Web, 2015, 29 July 2015



15

A Touch Screen; a solution for the future?

Authors: Alexis Diringer, Emmanuel Godet

Supervisors: Fabienne Floret, Carole Verlaguet

Laperouse high school

Abstract:

A touch screen is a computer device that combines the display features of a screen (monitor) and those of a point-

ing device like a mouse.

Nowadays, touch screens are increasingly present in everyday life. Until today, these technologies were rarely used

and available only on "outer terminals" as service stations or railway stations or airports, for example.

Recently, new technologies opened to the public have integrated screens or tactile devices. The recent release of

the last Nintendo DS console or phone Apple iPhone are examples of this new growth that can be explained by the

relatively low cost of touch screens, which became more accessible but also because the technology is more resistant

for regular use. The product has now evolved as it is stronger and accessible across the world.

Materials:

-Prototype

- Laptop

-webcam

Method:

As students, we face with this new type of technology, and therefore new methods of applications development. In the

first part, we will see the history of touch screen technology, detailing key dates and events wich have allowed a pro-

gress in this sector . Secondly, we will see the different types of touch screens. Then, we will present the screens in

daily lives. And finally, in the fourth part, we will try to see what innovations will bring touch screens in the future

Results:



16

We have created an even more environmentally friendly prototype digital tablet .Indeed our prototype is manufactured

entirely from the daily objects and we have the feeling that our touch screen has a neutral balance sheet as it is made

from recycled materials. Therefore that prototype is profitable on a long-term viewpoint and especially it can be done by

everyone as it is accessible and inexpensive.

Discussion and Conclusion: we have shown the évolution of touchscreens in history, the different types of

touch screen (capacitive, resistive ...) our prototype through the theme.. Then some recent innovations that will be used

in the future.

Acknowledgements:

We'd like to thank our professors Mrs. Verlaguet and Mrs. Floret for helping us all along this journey and putting their

trust in us .

Works Consulted:

Wikipedia, L'internaute, InterfaceTactile.com, TooBusinness.com , Tactyl.com, BeyondInfinite.com, La-

rousse,www.igm.univ-mlv.fr, TabletteTactile.net



17

Abstract: Due to the incredible mechanical properties of the silk and the structure of the webs, spider-webs could become a

revolutionary new material for the future.

Introduction: Used in the textile industry for centuries, spider-webs have shown a mechanical resistance and a relative elongation

(capacity to be deformed irreversibly without breaking) superior to other strong materials. Fascinated by this topic

matter, we have very willingly decided to thrive to unveil the secrets of this material. In order to study these mechanical properties, we have created a vivarium, in which we have, on several occasions,

raised different species of spiders (as we could not find their names we will call them the yellow, the black and the white

specie). We have also changed some factors to see if it would have any positive or negative impact(s) on the silk itself.

We have followed a strict scientific method by dividing our testing samples into two groups: a control group and an

experimental group where some spiders were drugged with alcohol, others were fed with sugar. Following a strict timescale, we have extracted the silk from the spiders (what we call the unreeling of silk), which were

anaesthetized with diethyl ether. Then, we have conducted several testing experiments on the silk thread: such as the

resistance tests (using weights) and the relative elongation computation. We are able, from the results we have gotten, to conclude if the silk of spiders can be a competitor to other well-known

materials already used today such as the nylon thread.

Materials: Mechanical resistance test: Relative elongation computation: - 1 spider - Scissors - Weights (1g, 2g, 5g, 10g) - Tape-measure - Unreeling silk device - 4 pieces of cardboard (of similar sizes)

- 2 support stands

Method: Essential in the conception and fabrication of technical objects, it seems more than important to study a few of the

diverse mechanical properties of the silk such as the mechanical resistance and the relative elongation. Therefore, after

extracting the silk from the spiders, we have decided to study and compare (between the different species and three

factors we have chosen) these two mechanical properties.

Method: Mechanical resistance test The mechanical resistance of a material is its capacity to resist to forces applying on it. We have therefore made up our

own method which will allow us to compare simply the mechanical resistance of the different silks tested using weights.

To simplify the results, we have made one bigger thread

(composed of five normal threads) by rolling the silk five times

around the unreeling silk device.

1. Place the unreeling silk device on the edge of the bench

at a sufficient distance from the ground in order to place

as much weights as needed. Ensure that the unreeling

silk device cannot move or fall during the experiment.

2. Place the weights one by one on the silk until it breaks.

Count the mass that the silk has carried and repeat this

experiment five to ten times in order to obtain a precise

average.

Spider’s Silk: a Future Material

Authors: Maxime Jung-Dupoux, Rodrigue Pakoa, Jasmine Jolliot, Sixtine Lebeau

Supervisors: Solveig Todman

Lycée Français de Port Vila



18

Method: Relative elongation computation While the deformation of a material we can count two distinct steps : the elastic deformation (reversible deformation)

and the plastic deformation (irreversible deformation). After some observations, we have decided to study this second

phase and therefore compute the relative elongation of the silk whose formula is the one below:

ε = With ε the relative elongation, lo the initial length (in cm), l the final length (in cm) and the

difference between l and lo (in cm). 1. After having extracted the silk, cut the thread obtained on the unreeling silk device and remove it holding its two

extremities.

2. Place the two support stands on top of the tape-measure (one has to be placed at 0cm and will not be moved

during the experiment). Place the two extremities of the silk in between the pieces of cardboard, themselves put

in the pliers of the two support stands.

3. Widen progressively the second support stand from the one placed

at 0cm and note its position when the thread is stretched. Measure

what we call the initial length, noted lo. Keep widening the second

support stand till the thread breaks. Note its position and measure

what we call the final length, noted l.

Results:

A: Mechanical resistance test

Observations and discussions

By means of the graph above presenting the resistance of the silk according to the species, we can establish the

classification of the various mechanical resistances of the spider’s silk studied. We distinguish clearly that the black

spider is in first position with its 33 grams, in front of the yellow spider (24g), itself followed closely by the white specie

(20g).

Although we are not capable of giving a real explanation to these results (we would have needed to study more

precisely the composition of the silk), we think that this difference between the tested silks comes from the different size

and mass of the spiders taken to undertake our study. In conclusion, the black specie seems wiser to use when

requiring an important mechanical resistance.

Observations and interpretations

It is obvious that according to the specie the reactions in front of changes diverge. Therefore, it is important to underline

that our results were obtained from averages but offer, nevertheless, a general vision of the impact of the various



19

changes of diet on the silk of spider. The graph above presents, thus, the average of the resistance of the silks tested

according to the diets (alcohol, sugar) without any distinction between the species.

The drugged specie (25g) seems to have a rather unimportant impact on the resistance of the silk as we observe that

there is only 1 gram difference between the resistance of this one and the control group specie (26g).

The specie fed with sugar, contrary to our hypothesis, seems to affect the mechanical resistance. Unfortunately, our

knowledge does not allow us to propose any explanation to this result except that it could come from the chemical

composition of sugar.

In conclusion, we can say that none of the modifications made any improvement in the resistance of the silk. So, if

needing spider silk, it seems more interesting to use the silk thread as it is and not try to improve it with sugar nor

alcohol.

B. Relative elongation computation


By means of the graph above presenting the relative elongation of the silk according to the species, we can, as for the

resistance, establish the classification of the various relative elongations of the spiders studied. We note clearly that the

yellow spider, this time, is in first position with its 270%, in front of the white specie (210%) and the black specie (180%). One more time, we think that these differences in the results obtained are due to the different silks produced by each spider.



20

To conclude, it would thus seem more interesting to use the yellow specie when needing a material with an important relative elongation, or a big capacity to resist to a plastic deformation.


When studying the graph above we can observe that alcohol seems to improve the relative elongation of the silk. Our

interpretation to this surprising observation is the presence of hydrogen connections in the composition of the silk.

Indeed, the molecule of alcohol has the capacity to form hydrogen connections thanks to the strong difference of

electronegativity between its atoms of hydrogen and oxygen. These connections between molecules would allow an

important plastic deformation of the silk, what would confer him his ductile character.

Contrary to what we first thought, the sugar confers one more time no advantage on the silk. In this case also, our

knowledge of the subject cannot lead us to propose any element of answer.

To conclude, we can say that the alcohol boosts the capacity of the relative elongation of the silk, granting him a relative extension higher than normal. So, if needing an important relative elongation, the use of alcohol would allow to improve the mechanical resistance of the silk and obtain therefore better results.

Conclusion: Following our study, we can emit the hypothesis that the changed parameters (sugar and alcohol) have an influence on

the mechanical properties of the silk of spider. We can therefore think that the sugar does not really improve these

properties contrarily to alcohol. If we had had more time, we would have been able to deepen this result; it remains a

simple hypothesis which would be necessary to study again more precisely. We can conclude that the silk of spider can

be a material of the future both because of its exceptional mechanical resistance and capacity to deform. This surprising

material surpasses the nylon thread in certain domains and is therefore a potential competitor to other materials used

today. Spider’s silk can be used in numerous fields such as in architecture, in the medical field or in the textile industry.

Acknowledgments:

We would like to thank our two teachers, Mrs Cabane and Mr Peype, as well as Anaïs Bresque for helping us and

making this project possible.



21

Study of Propagating Properties of Leaky Surface Wave on the Silicon Single Crystal using Line Focused PVDf Transducer

Authors: Sungjun Kim, Yoonho Noh, Mincheol Son, Dongjin Lee, YoungH Kim

Supervisor: YoungH Kim

Korea Science Academy of KAIST

Abstract

In this research, we measured the velocity of Leaky Acoustic Surface Wave(LSAW) on the monocrystalline Silicon

with different propagation direction using large aperture line-focused PVDF transducer of radius 25mm which we

made. We used the phenomenon that when the distance between silicon specimens with different crystal direction

and the transducer increasing, then directly reflected longitudinal wave and Leaky Acoustic Surface Wave(LSAW)

separate as the time flows. For the silicon specimens, with crystal direction [1,1,1], [1,1,0], [1,0,0] were used for the

measurement. Based on the measurement result, we could certain that the graph demonstrating Leaky Acoustic

Surface Wave(LSAW)’s time of arrival while changing the propagation direction was similar with the graph showing

shear modulus at each direction and therefore we could find the crystal directions.

Introduction

When solid specimen and water forms a boundary, leaky surface acoustic wave is being able to propagate along

the surface of specimen. In this research, we investigated the propagation property of the leaky surface acoustic

wave(LSAW) using PVDF transducer, which is quite easy to fabricate and showing propagation of LSAW visually,

on the anisotropic materials. We graphed the elapse time of the LASW as changing cutting direction of the cubic

crystal structured silicon wafer. After that, we could confirm the crystal direction by comparing the elapse time graph

with the graph demonstrating shear modulus on each direction

Method

Figure 1 Two different propagating ways

Figure 1 is a picture depicting two acoustic line which affecting to practical observation. Path I demonstrates the

directly reflected wave, Path II is a wave which has incident angle as critical angle, it propagates along the surface

as a form of Rayleigh wave by Snell’s law, incidents as a compressional wave by mode conversion at symmetric

point.

As varying the defocusing length z, we can control the time interval of surface wave and reflective wave’s separa-

tion. So we can evaluate the velocity of the surface wave by calculating the slope of the time difference versus defo-

cusing length z difference. Denote as elapsed time for path I, as elapsed time for path II. Then the velocity of the

leaky surface acoustic wave can be evaluated by following formula.



22

We fabricated transducer by taping PVDF with thick 28um, width 11mm, length 52mm to backing material using

epoxy. Here, backing material’s acoustic impedance is 3.8Mlayl and transmittivity is 99%, so that minimize the effect

that reflected wave affect to the measurement. Also, we shielded with aluminium case for minimizing the noise from

outside electromagnetic waves.

Figure 2 Experiment device system

Figure 2 demonstrates the devices we used for experiments. Panametrics NDR-5800 was used for acoustic wave’s

transmitting and reception. We could control the transducer’s position by x, y, z stage and National Instruments’ Mo-

tion Controller MID-7604.

Results

Figure 3 Young's modulus and shear modulus of monocrystalline crystal



23

Figure.4, Elapsed time in propagation direction [1, 0, 0]

Figure 5, Elapsed time in propagation direction [1, 1, 0]

Figure 6, Elapsed time in propagation direction [1, 1, 1]

Discussion and Conclusion

From the experimental results, we could confirm that shape of graph of shear modulus and elapsed time is similar in

two silcon wafer having same cutting direction. It's because, in general, shear modulus is proportional the speed of

the shear wave, and the speed of the Rayleigh wave is 80~90 % of the shear wave speed.[3] Hence, shear modulus

and Rayleigh wave speed is reciprocal. But, shear modulus graph's axis is not determined, and if we make reciprocal

of the speed, it becomes elapsed time graph, here phase is pi/2 changed. Therefore, overall graph's shape must be

similar to the shear modulus graph

Acknowledgements

This research’s continuation was promoted by Korea Science Academy of KAIST R&E Program Support. Special

thanks to Dr. Lee who assisted making transducer a lot

Works Consulted

1. D.Xiang, N.N. Hsu, G. V Blessing "The design, construction and application of a large aperture lens-less line-focus

PVDF transducer",November 1995

2.Hyuck-Joon Yoon, LSAW Velocity Measurement by Using a PVDF Line-Focus Ultrasonic Transducer J. Acoust.

Soc. Kor. Vol. 20, No. 1

3. Howard F. Pollard “Sound waves in solids”,1997



24

Jinan Aquatic Phytoplankton Investigation

Authors: Shang Runyu, Shang Tianze, Han Runting, Fu Yixuan, Yang Chenglin, Sun Yuqiao

Supervisor: Li Lin

The Middle School Attached to Shandong University

Abstract:

To make a aquatic phytoplankton preliminary investigation of Ji-nan.

Introduction:

Discovered more than 20 kinds of phytoplankton,and summarize the relationship between water quality and

phytoplankton species.

Materials:

microscope camera water sampler water bottle

Method:

observational method experimentation investigation method

Results: ie graphs / photos / written report


Jinan has rich resources of aquatic phytoplanktons,and some aquatic phytoplanktons can indicate the pollution

degree of water quality.

Acknowledgements:

Thanks for the ASMS INTERNATIONAL SCIENCE FAIR; thanks for the Australian Science and

Mathematics School, Adelaide; and thanks for our school and our teachers.

Works Cited:

Preliminary Investigation on Phytoplankton and Estimation to Fish Productivity of Heiyu Lake in Daqing.

Works Consulted:

THE MIDDLE SCHOOL ATTACHED TO SHANDONG UNIVERSITY.

ShanDong Normal University.



25

Abstract:

The research aims to study the extraction of crystallized cellulose (CC) from rice straw and the preparation of

the CC/chitosan composite film. The rice straws were washed with water and dried at 50 ˚C. Then they were cut into

small pieces with the length of 4-5 cm. Then they were left in 4% (w/v) NaOH for 2 hours, then washed with water and

dried at 50 ˚C. Repeat this step for another two times. One gram of rice straw was subsequently bleached by

bleaching solution (1.5 g of NaClO2 + 25 mL of water + 5 mL of conc. CH3COOH) at 70 ˚C for 1 hour. The bleached

cellulose was then washed and dried at 50 ˚C. It was subsequently mixed with 40 mL of 0.05 M HNO3. The mixture

was heated at 70 ˚C for 1 hour to obtain the partially hydrolyzed cellulose. This cellulose was further hydrolyzed by

55% H2SO4 for 2 hours. The cellulose from each extraction step was analyzed by X-ray diffraction technique. The

composite was prepared by dissolving chitosan (various amounts) in 4 % (w/v) CH3COOH and CC (various amounts)

was then added into the chitosan solution. The mixture was left stirring for 1 hour at room temperature. It was then

poured into the petri dish and left at room temperature for 24 hours for gelation process. The wet film was then dried

at 50 ˚C for several hours to obtain CC/chitosan composite film. From the tensile measurement, the film containing

0.5 % chitosan (no cellulose) shows the highest tensile strain. While the film with 1.0 % chitosan shows the highest

tensile stress. The films containing both chitosan and cellulose show lower tensile strain and stress. From TGA

measurement, pure chitosan film starts decomposing at 310°C and the composite films containing cellulose start

decomposing at lower temperature.

Introduction:

The growing number of people in each country increases the consumption of food. High amount of waste is

produced especially plastic containers. These synthetic polymers are not easily degraded and cause environmental

problems. To decrease these non-degraded polymers, natural polymers like chitosan and cellulose are of interest.

The film prepared from these natural polymers can be used in place of synthetic polymers. In this research, the

cellulose extraction from rice straw were performed to obtain cellulose with high crystallity. The crystalline cellulose

was then used for fabrication of cellulose/chitosan composite film.

Objectives

To extract crystalline cellulose from rice straw To prepare cellulose composite films To study the strength properties of the prepared film

Materials:

1. Acetic acid (glacial) (CH3COOH)

2. Chitosan

3. Nitric acid (HNO3)

4. Sodium hydroxide (NaOH)

5. Sodium hypochlorite (NaClO)

6. Sulfuric acid (H2SO4)

Method:

1. Preparation of crystalline cellulose extracted from rice straw

Preparation of Composite Film Using Crystalline Cellulose Extracted from Rice Straw

Chanida Jirapintu1 and Mataporn Limvoraphan1

Sasinee Ungkanont1 and Asst. Prof. Dr. Radchada Buntem2

1Mahidol Wittayanusorn School

2Department of Chemistry, Faculty of Science, Silpakorn University



26

1.1 Wash rice straws with water and dried at 50 ˚C to produce RH1. Cut them into small pieces (4-5 cm in

length).

1.2 5 g of RH1 was added 150 mL of 4% (w/w) NaOH and the mixture was refluxed for 2 hours. Wash with

water and dry at 50 °C. Repeat this step for 3 times.

1.3 1 g of fiber from 1.3 was bleached by 5 mL conc. acetic acid and sodium chorite solution (1.5 gram in

25 mL of water). Then the fiber was washed by water in water bath at 70°C for 2 hours to produce

RH2.

1.4 1 g of RH2 was added 40 mL of 0.05 M Nitric acid and the mixture was refluxed for 2 hrs and the fiber

was washed by water at 70°C for 1 hours to produce RH3.

1.5 1g of RH3 was added 40 mL of 6M sulfuric acid to produce RH4.

1.6 RH1, RH2, RH3 and RH4 were analyzed by X-ray diffraction.

2. Forming composite film

2 .1 Dissolve chitosan in acetic acid 10%(v/v) to make three concentrations :

0.5%(v/v), 0.75%(v/v), 1%(v/v) 2.2 Four different weights of RH4 : 0 g, 0.1 g, 0.2 g, 0.3 g, were mixed with 200 mL of chitosan solutions

in 2.1.

2.3 Each of 12 solutions from 2.1 was poured into petri dish and the wet film was then dried at 50 ˚C to

obtain CC/chitosan composite films.

Results:

Fig.1 XRD patterns of RH1, RH2, RH3 and RH4

Fig. 1 shows the XRD patterns of celluloses from four different extraction steps: RH1 (blue line), RH2 (red line), RH3

(green line) and RH4 (purple line). The highest % crystallinity was obtained from RH3. The hydrolysis using sulfuric

acid is not necessary for extracting cellulose with high crystallity.

A) B)



27

C)

Fig.2 Strength plots of composite film (a) tensile stress (b) tensile strain (c) Young modulus

Fig.2 shows all strength plots: tensile stress or the ratio of force that perpendicular with the surface area, tensile

stain or the ratio of length that increasing with the original length and young’s modulus or the ratio of tensile stress

and tensile strain. The best tensile stress and strain were obtained from the film prepared from 0.1 g cellulose in 1%

chitosan solution. While the film prepared from 0.3 g cellulose in 1% chitosan solution gave the highest young ’s

modulus. TGA measurement was also performed to determine thermal stability of the film. It was found that pure

chitosan film decomposed at 310°C and the composite films containing cellulose decomposed at 224°C..


The best method for extracting cellulose is as follows: extracting with sodium hydroxide, bleaching by 5 mL of

17.4 M acetic acid and 25 mL of 6% (w/v) sodium chlorite (per 1 g of rice straw) and hydrolysing by 0.05 M nitric acid.

The extracted cellulose is small white precipitate, which can be swelled in water. The blend cellulose-chitosan film

was prepared by mixing 200 mL 1%(w/w) chitosan solution and 0.3 g cellulose. This film has the hightest young’s

modulus of 7.91 MPa. TGA data showed that the extracted cellulose started decomposing at 310 °C and the blend film

started decomposing at lower temperature. The blend film will be attempted for another tests like antimicrobial activity,

hydrophobicity and porosity in order to being used as the food packaging.

Acknowledgements:

- Department of Chemistry, Faculty of Science, Silapakorn University

- Mahidol Wittayanusorn School

- Research and development centre for Thai Rubber Industry

Works Cited:

- Mahidol Wittayanusorn School


Works Consulted:




28

Abstract:

Formaldehyde is a toxic material that can kill bacteria and viruses as well as damage human cells. Food

manufacturers sometimes add formaldehyde to food such as fish, noodles, vegetables, seafood and meats to extend

its shelf-life. A lot of typical food naturally contain small amounts of formaldehyde; however, excess formaldehyde has

been reported in many food products. The objective of this research is to produce a test kit for determination of

formaldehyde in solution of food. Pararosaniline in ethanol (0.001M: 2 mL), hydrochloric acid (6M: 2mL) and

formaldehyde solution were mixed in a bottom. The activity was monitored by following the color change from yellow

to violet. The detection limit of test kit was 125ppm.

Introduction: Formaldehyde is used in many industries and in medication. Nowadays, a lot of food products have

formaldehyde, Manufactures put it into food to keep it fresh. The concentration of formaldehyde starts to affect the

body at 40 ppm. Most of people use at 210-780 ppm. It can cause irritation to the stomach or diarrhoea, can damage

kidneys and can cause death. Although there are many methods for testing formaldehyde, some methods are difficult,

expensive, or taking a long time. The objective of this research is to produce a test kit for determination of

formaldehyde in solution of food.

Materials:

2,4-dinitrophenylhydrazine (2,4-DNP), 4-Amino hydrazine-5-mercapto-1,2,4-triazole (AHMT) and pararosaniline were

tested for determination of formaldehyde solution.

Method:

Study reaction of 2,4-DNP, AHMT and Pararosaniline

Select the appropriate chemical substances

Find the optimum condition

Study the colour were made by the eyes

Study the difference of colour by UV-vis.

Test the test kit with the slice ginger.

Results:

Result of 2,4-DNP

It cannot measure dreg occur. So, it is not good for using 2,4 - DNP to make

the test kit.

Result of AHMT

It is very sensitive with formaldehyde also in the air. It is

hard to separate different concentration by eyes.

A Test Kit for Determination of Formaldehyde in Solution of Food

AUTHORS: Chutikarn Sinlapasunthorn1 and Natthikul Thanteeraphap1

SUPERVISORS: Sorachai Sae-lim1 and Hiranrat Suwannatee2

1Department of Chemistry, Mahidol Wittayanusorn School, Thailand,

2Department of Chemistry, Faculty of Science, Silpakorn University, Thailand



29

Result of Pararosaniline

It can see the change of colour. So, it is good for using this chemical

to make the test kit.

Pararosaniline reagent exhibited high sensitivity and selectivity towards formaldehyde solution. Pararosaniline in

ethanol (0.001M: 2 mL), hydrochloric acid (6M: 2mL) and formaldehyde solution were mixed in a bottom. The activity

was monitored by following the color change from yellow to violet. The absorbances were measured at 586 nm. The

detection limit of test kit was 125ppm.

This is a chart for testing colour of formaldehyde.


Pararosaniline for making test kit because

It just took 10 minutes, then colour did not change.

It could separate difference of colour by eyes at less concentration of formaldehyde at 250 ppm.

It could detect formaldehyde at less 125 ppm

It was not sensitive with the air.

The result may have some deviation because formaldehyde is gas that can dissolve with the air. Water from sliced

ginger has colour then it can make colour of solution is not clear.

Acknowledgements:

Department of Chemistry, Mahidol Wittayanusorn School

Department of Chemistry, Faculty of Science, Silpakorn University

Works Cited:

Department of Chemistry, Mahidol Wittayanusorn School

Department of Chemistry, Faculty of Science, Silpakorn University

Works Consulted:

[1] Reproductive and developmental toxicity of formaldehyde: A systematic reviewAnh Duonga, Craig Steinmaus a,b,

Cliona M. McHalea, Charles P. Vaughanc, Luoping Zhanga. Reproductive and developmental toxicity of

formaldehyde: A systematic review. Mutation Research. 728 (2011). 118–138.

[2] Po-Ren Chung, Chun-Ta Tzeng, Ming-Tsun Ke, and Chia-Yen Lee. Formaldehyde Gas Sensors: A Review.

Sensors 2013. 13(4). 4468-4484.

[3] R. Ikan. Natural Products, A Laboratory Guide. Israel Universities Press. 1969.



30

Abstract

Salicornia europaea has potential as an alternative crop. This project aims to germinate and cultivate a halophyte,

Salicornia europaea, in a tropical climate and ultimately to integrate it into a marine aquaponics system. The

variables tested for germination were germinating media, salinity, photoperiod and temperature. As for the growth of

S.europaea, the light intensity and nutrients supplemented were varied. The germination phase was done in an

environmental chamber while the growth phase was carried out outdoors. The highest germination recorded was

24% when germinated in sand with vermiculites. Also, at the start of the growth phase, the halophyte had the highest

growth rate when nutrient is present and under mild sunlight while stronger sunlight is required subsequently.

Introduction

Due to the growing population and scarcity of land and freshwater, Singapore depends largely on imports for

agricultural products. This could be a problem if the supply of agricultural products decreased and the cost of these

products increase. Researchers have already started investigating the potential of using halophytes to solve this

problem. Marine aquaponics has not been studied as much as freshwater aquaponics. Halophytes have significant

economic and ecological benefits, hence we want to look into this aspect and study the feasibility of culturing

halophytes with marine culture in an aquaponics system in Singapore’s climate. Singapore has to come up with

efficient ways to grow crops, using all available resources in order to feed itself, including utilizing the abundance of

seawater. Researchers have been investigating the economic value of halophytes to tackle the problem of

insufficient food supply. Therefore, the research on ways to utilize saline water to cultivate halophytes which can be

used as alternative crops is crucial.

This study will provide a review on Salicornia europaea and explore its ability to thrive in a tropical climate. S.

europaea has never been cultivated in a tropical climate like Singapore before, and this is the first study of such. The

aim of this project is to enhance the germination rate of S. europaea, a halophyte, by germinating it under the best

set of conditions and eventually, to culture it in a marine aquaponics system.

S. europaea is a highly salt tolerant halophytic species occurring in coastal marshes of North America. It is an annual

dicotyledon that flowers in August and its seeds ripen in September. S. europaea grows in pure stands on the most

highly saline locations of an inland saline pan at Rittman, Ohio. It is especially popular in Europe as widely used and

consumed as delicacies the US market. It has economic and ecological benefits. It can be used as an alternative

food crop and it also removes excess nutrients from fish culture, preventing algae overgrowth.

Materials

The materials used for germination phase are: 5-litre packs of fine vemiculites, sand and LECA balls, cotton wool,

plastic containers (19x32x10.5cm) and a Versatile Environment Test Chamber. The materials used for growth phase

are: Styrofoam boards, general nutrient solution, 2-inch net pots with square top and a lux meter.

Methodology

Germination and Growth of Salicornia europaea in Singapore

Brandon Lam, Heng Shi Ning

Prof. Lam Toong Jin, Dr Dao Huy Giap, Mr Lee Siak Cheong

NUS High of Mathematics and Science



31

The experiment involved two phases: germination and plant growth. In order to refine the germination and growth

conditions, the variables tested included temperature, photoperiod, light intensity, germination media, nutrient

requirement and salinity.

Results

The results for germination phase are tabulated below:

The results for growth phase are summarized in the graphs below:



32

Discussion and Conclusion

Pre-germination: When attempting cold stratification, the S.europaea seeds were all swollen as the water had diffused

into the seeds and there was no germination recorded for that batch of seeds. Later, we put another batch of seeds

under the sun for three hours prior to germination to allow heat shock when the seeds were placed into a cooler

condition. The resultant rate of germination was 1%. Also, we pre-heated the seeds in the oven for 3 hours at 60° C.

The rate of germination was 6%. However, without any treatment, the seeds germination rate was 13%. Hence, pre-

treatment is not necessary for the germination of S.europaea.

Germination: The best germination media was sand mixed with vermiculites. This is probably because sand is well

drained and looser, which allowed the roots to get a foothold, while vermiculite is able to retain moisture in the sand.

The best salinity for the germination of S. europaea is 0 ppt fresh water. S.europaea, when exposed to hyper-saline

conditions maintained an enforced dormancy that is alleviated with the availability of freshwater and germination is

inhibited by the increase in salinity. Photoperiod optima for germination was 16 hours daylight and 8 hours night. This

suggests that germination is optimal under longer daylight. The exposure to longer periods of daylight might have

stimulated the phytochrome in the S.europaea seeds, causing seed germination (Leite and Takaki, 2001).

Growth of seedlings: The growth of S.europaea required nutrients as the set-up without nutrients wilted. However, the

specific nutrients required for the growth of the seedlings has not been defined yet. The early stages of growth

required mild intensity of sunlight, preferably below 10000 lux. Some shelter from the rain was also required. Less

exposure to both sunlight and rainwater is more suitable for the start of the growth of S. europaea. After 3 weeks, the

plants require stronger sunlight for photosynthesis.

Results from all experiments pointed towards the following conclusions. The 16 hours daylight 8 hours night

photoperiod, equivalent to spring/summer condition in temperate climates, is more suitable for germination of S.

europaea. Germination rates was recorded to be highest in freshwater. The best germination media for S.europaea

turned out to be sand with vermiculites with a germination rate of 24%. In the growth phase, sunlight of weaker

intensity (below 10000 lux) is the most optimal for S.europaea.

We were successful in improving the germination rate of Salicornia europaea by refining the optimal conditions as

compared to the study on Salicornia bigeloveii by Lye Jia Mei (2013). The highest germination rate obtained in this

study was 31%. Also, the maximum plant height obtained in phase 2 of this study was 19cm, 6 weeks after

germination.

Acknowledgements

The project was proposed and supervised by Emeritus Professor Lam Toong Jin and Dr Giap. We would like to

express our gratitude to them for their guidance, support and encouragement. We would also like to thank Tropical

Marine Science Institute for the use of facilities

Lastly, we would like to express thanks to our project mentor, Mr Lee Siak Cheong, who oversaw us throughout the

whole project.



33

Work Cited

Ajmal Khan, M., Gul, B. and Weber, D. (2000). Germination responses of Salicornia rubra to temperature and

salinity. Journal of Arid Environments, 45(3), pp.207-214.

Ashby, W. (1960). Salt Marshes and Salt Deserts of the World. V. J. Chapman, Leonard Hill, London; Interscience,

New York, 1960. Science, 132(3427), pp.614-615.

Egan, T. and Ungar, I. (2000). Similarity between seed banks and above-ground vegetation along a salinity

gradient. Journal of Vegetation Science, 11(2), pp.189-194.

Kumar, R. (2013). Seed Germination of Stevia rebaudiana Influenced by Various Potting Media.Octa Journal of

Biosciences.

Leite, I. and Takaki, M. (2001). Phytochrome and temperature control of seed germination in Muntingia calabura L.

(Elaeocarpaceae). Brazilian Archives of Biology and Technology, 44(3), pp.297-302.

Lye Jia Mei, C. (2013). Hydroponics Cultivation of Salicornia, National Technological University.

Olakaihawaii.com, (2015). Olakai Hawaii sea asparagus ogo. [online] Available at: http://olakaihawaii.com/about

[Accessed 9 Jan. 2015].

Ungar, I. (1977). Salinity, temperature, and growth regulator effects on seed germination of Salicornia europaea

L. Aquatic Botany, 3, pp.329-335.

Ventura, Y. and Sagi, M. (2013). Halophyte crop cultivation: The case for Salicornia and Sarcocornia. Environmental

and Experimental Botany, 92, pp.144-153.

Work Consulted

Lye Jia Mei, C. (2013). Hydroponics Cultivation of Salicornia, National Technological University.



34

Abstract: Rapid development and industrialization have invariably been brought up as an anthropogenic cause for pollution such as the release of heavy metals into the environment, especially in a developed country like Singapore. As heavy metals are not biodegradable and persistent in the environment, it is important that levels of heavy metals in the environment are consistently monitored by suitable bioindicators. Existing methods such as chemical analyses that are a measure of habitat are laborious and time-consuming. Many bioindicators reported are either not sensitive or too sensitive. In this project, we demonstrate the feasibility of using Thais gradata (sea snail) as a bioindicator for heavy metals through a suite of behavioural, physiological, and biochemical indices, supported by its abundance and wide distribution in nature. Introduction: Mangroves represent a critical ecological habitat to a diverse range of marine fauna. They once covered an estimated 13% of Singapore’s total land area, but represent less than 0.5% today. As heavy metals are not biodegradable and persistent in the environment, they can be bioaccumulated in organisms and magnified in the food chain. Of particular interest is Cu, which is one of the most common and toxic heavy metals present in the environment. Cu is also essential to drive several important biochemical processes yet toxic at excessive levels. Imbalance between copper necessity and toxicity in favour of the latter essentially translates into damage at the cellular level and at the tissue and organ levels. These changes can be investigated by simulating acute and chronic conditions that closely reflect the upper and lower tolerance limits determining species survival and therein extrapolation to habitat integrity. Currently, Thais gradata has not been extensively studied for its feasibility as a bioindicator, but its abundance and wide distribution especially in the intertidal zones of rocky shores makes it a potential candidate. Materials and Methods: Thais gradata (shell length 3.0 ± 0.5 cm) were collected from the Mandai Mudflat, cleaned and placed in artificial seawater to remove any traces of heavy metals at 28 oC. Snails were submerged into various Cu concentrations for 7 days to carry out lethal assay, behavioural, physiological and biochemical tests. Behavioural Analysis. During the course of 7 days, the number of T. gradata that climbed out of the water was labelled as active survivors. Passive survivals refer to those that stay in the water. Neutral Red Retention Time. Haemolymph was collected in siliconized microtube and centrifuged. The supernatant was kept aside for FRAP assay while the pellet was immediately mixed with physiological saline solution. Cell suspension was placed onto the poly-L-lysine coated microscope glass slide before incubation in a light proof humidity chamber. Excess haemocyte mixture was removed and working neutral red solution was added. The slides were systematically examined under a light microscope at intervals. Ferric Reducing Antioxidant Power Assay (FRAP). Ferris oxidised Iron standards were prepared. Isolated supernatant was placed into siliconised microtubes on ice. 250 μl of each standard was loaded into two wells for replicates, followed by the 250 μl of haemolymph as well as 1 ml of reagent (Acetate buffer, TPTZ, Iron(III) Chloride). A spectrophotometer was then used to read absorbance at 593 nm. Anthrone Assay. Foot muscles (40 - 50 mg) were cut weighed and immersed into a solution of 30% KOH, followed by boiling at 100oC for 20 to 30 min until full dissolution. Absolute ethanol was added to each sample and cooled on ice overnight. The tubes were then centrifuged, and the pellet was reconstituted by re-dissolving it in distilled water. 1 ml of Anthrone reagent was added to 50 μl of each sample and boiled. Absorbance was measured at 620 nm. Results: LC50 on Day 7 is approximately 1.0 mg/L (sublethal concentration). Behavioural analysis shows that T. gradata is more likely to close its operculum to avoid contaminants under stressful condition because on Day 7, snails subjected to high concentration are significantly lesser than those subjected to low concentration (Fig. 1). Neutral Red Retention demonstrates lysosomal instability of T. gradata when exposed to high concentration of contaminants under chronic condition. There were consistently more lysosomal breakages of haemocytes subjected to high concentration. By the

Exploring the Feasibility of using Thais Gradata as a Bioindicator for Heavy Metals to Monitor Environmental Pollutants using Copper

LIM SEOK HWAN, LOH DE RONG

GOH YAN YIH

NUS HIGH SCHOOL OF MATH AND SCIENCE



35

120th min, percentage of cells with lysosomal breakages almost reached and exceeded 50% end point in Fig. 2a and Fig. 2b respectively. Ferric Reducing Antioxidant Power Assay indicates unusually high oxidative stress experienced by T. gradata at higher levels of contaminants, as evident by the significant increase in antioxidant power from control to 1.0 mg/L (Fig. 3). The Anthrone Assay is a further proof of the previous indices, as it shows the most significant drop in glycogen level for the highest concentration on Day 7, relative to other concentrations (Fig. 4).

Figure 1 Figure2a Figure 2b

Figure 3 Figure4 Summary of the results of all biological and chemical indices. Figures 1, 3 and 4 use T-test analysis. * indicates significant difference between two samples; p < 0.05. ** indicates significant difference between two samples; p < 0.01. Error bars indicate the standard errors of the mean values. Discussion and Conclusion: T. gradata subjected to high Cu concentration for an increased exposure period tend to avoid the contaminated water using their operculum, which prevents them to undergo aerobic respiration. This is usually followed by death the next day. The drop in glycogen level for all concentrations could be accounted by the need to produce energy for basic metabolic activities via the conversion of glycogen. Snails subjected to high Cu concentration require more energy as they constantly contract their muscles to hide in their shells. Furthermore, most metabolic pathways to cope with stress (e.g. stress protein production) are energetically demanding, resulting in greater glycogen reduction. Most of them are thus observed to turn to passive survival which unfortunately entails imminent death. At the cellular level, there were more lysosomal breakages observed for a higher concentration and an increased exposure time to xenobiotics, which is yet another indication of stress before death. The spillage of contents leads to digestion of its cell as well as surrounding cells, causing necrosis, tissue damage and eventual death. The high oxidative stress could also lead to cell necrosis. An increased production of antioxidants is needed to counteract the increase in ROS as excessive amounts of ROS are hazardous for living organisms and damage all major cellular constituents. The subsequent death of many snails that were subjected to high concentration after a surge in antioxidative power on Day 7 suggests that they do not have sufficient glycogen for ATP production to support basic metabolic activities or antioxidative response.



36

All the biological indices followed a sensitivity hierarchy: behavioural, systemic, cellular.. Our results clearly shows this trend, as evident from the closure of the snail’s aperture to avoid the contaminated water, the destruction of lysosomal membrane, the increase in antioxidants (or oxidative stress) and finally the eventual drop in glycogen store. They all represent a series of events that occur leading to almost 50% mortality of those T. gradata that were exposed to high levels of contaminants in a span of 7 days. The extremely strong correlation between all these results demonstrating its sensitivity even at such a microlevel is thus a noteworthy point which proves the suitability of T. gradata as a bioindicator. Acknowledgement: We would like to thank Dr Goh Yan Yih for his time in guiding us throughout this project. We also want to thank NUS High for funding the project and providing the facilities. Works Cited 1. Bayen S.; Wurl O.; Karuppiah S.; Sivasothi N.; Lee H. K.; Obbard J. P. Persistent Organic pollutants in Mangrove Food Webs in Singapore. Elsevier Chemospere. 2005, 61, 303-313. 2. Gaetk L.M.; Chow C. K.; Copper toxicity, oxidative stress, and antioxidant nutrients. Toxicology. 2003, 189(1-2): 147-63. 3. Lloyd R. V.; Hanna P. M.; Mason R. P. The origin of the hydroxyl radical oxygen in the Fenton reaction. Free Radic Bio Med. 1997, 22(5): 885-8. 4. Michael P. Lesser. Oxidative Stress in Marine Environments: Biochemistry and Physiological Ecology. Annu. Rev. Physiol. 2006, 68: 253-78. 5. Goh B. P. L.; Lai C. H. Heavy Metal Levels in Marine Sediments of Singapore. Environmental Monitoring and Assessment. 1997; Vol. 44 1-3 pp 67-80.

2



37

Abstract:

TEGO-C composite material was synthesized in scalable amounts by thermal exfoliation method. Fine GO dry

powder was heated at 3500ºC for a few seconds in a tube furnace to obtain exfoliated structure that is TEGO powder,

where graphene layers are separated thus resembling a ‘puffy’ physical structure. Synthesised TEGO powder was

then used to prepare electrodes, which are used as anodes to fabricate LIBs coin cells. Our methods allows for

TEGO bulk production unlike chemical exfoliation of TEGO. [1, 2] This method is simple solid state, one pot, eco-

friendly, no separate chemical reducing agent required, no toxic by-products (except for gases like CO, CO2).

Furthermore, no post production treatment like purification is required, as prepared material can be directly used for

applications like anodes of Lithium Ion Battery (LIB). Electrochemical studies of these LIBs were done by using

Galvanostatic cycling (GC), cyclic voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The ratio of

TEGO, Super P carbon and PVDF was varied in the slurry prepared for the formation of the anode, to investigate into

the optimal ratio of TEGO to Super P carbon. The ratios selected were 40:40:20, 65:20:15, 70:10:20; pure graphite

and pure TEGO alone in ratios of 80:20 were also tested as a control. TEGO 65:20:15 and TEGO 70:10:20 showed

the most promise among the samples due to low voltage hysteresis, stable capacity retention as well as boasting

capacities higher than that of SPC even when cycled at high current rates of 400mA/g. However TEGO 60:20:20

shows significantly lower bulk resistance than TEGO 70:10:20 in EIS analysis, making it the overall most optimal

compound with largest potential for industrial applications.

Introduction

Li-ion batteries are increasingly popular and constitute a vital part in today’s world. [3] Not only do these batteries

have higher capacity than traditional alkaline batteries, it is also rechargeable and cheap to manufacture. In view of

the increasing demands needs of newer battery applications, the current technology of the conventional Li-ion

batteries would not be able to meet up. Firstly, they use graphite as the anode that results in low capacity and easily

allows formation of potentially dangerous dendrites when cycled at high current rates. [4] However for anodic

application nothing can be dearer than the commercial graphite as it offers maximum discharging and charging

capacities lies around 0.15-0.25 V with least hysteresis, but it shows lower practical capacities 330-360 mAh/g (even

at lower current rates) out of its theoretical capacity of 372 mAh/g. As more and more new devices require more

power, especially in electrical cars, it is necessary to explore other anode materials that could better address the

disadvantages of the commercial Li-ion batteries mentioned above, while being economical. To this end, graphene

and its related compounds have shown great promise as prospective anode material for lithium ion batteries – due to

their high reversible capacity. However they experience a high irreversible capacity loss (ICL) during the first

discharge cycle. This may be attributed to the high BET surface area, which although conventionally may be

beneficial, in this case causes the solid electrolyte interphase (SLI) to have a strong adverse effect on the ICL value

of the battery. Precursor research has been conducted on exfoliated graphene oxide through synthetic chemicals

method [1, 2]. However, chemical exfoliation has failed to produce it in bulk quantities and previous literature studies

shows little or no research done on TEGO as anode material much less cover varying ratios of TEGO to super P

carbon (SPC). In this project we aim to find the optimal ratio of TEGO: SPC: Polyvinylidene Fluoride (PVDF), to

obtain an improved anodic material as compared to commercial graphite.

Materials:

Lid with plastic ring & steel spring

Coin cell cup

Li metal foil Anode(Kyokuto Metal company, Japan

Microporous Separator (Poly propylene (Celgard 250 membrane)

Optimized Cathode/Anode materials

Electrochemical Studies of 'Thermally Exfoliated Graphene Oxide-Carbon' Composite in Varying Ratios as Potential Anode Material for Batteries

Amos Sim, Keefe Wayne Teo, Luo Chen

Dr M.V.Reddy

NUS High School of Maths and Science



38

Method

3.1. Characterization

XRD (Empyrean Pananlytical) was performed using CuKα radiation (wavelength 1.5418Å), and the technique used to

investigate the compounds is the Bragg’s Brentano XRD technique. XRD patterns were taken at 40 kV, 30 mA and at

step size 0.02°/s. Refinement of the data will tell us about the lattice parameter and average crystallite size of our

compound. Morphological studies were carried out by using field emission scanning electron microscope (FESEM)

(Model Ultra 55 of Carls Zeiss-Germany). Electron micrographs recorded with accelerating voltages of 5 (FESEM) at

various magnifications. The Bitrode multi-channel tester [MCV16-05/001-5, Bitrode, USA] was used for charge-

discharge cycling of the batteries. Raman spectra (Renishaw Raman system 2000) were recorded with auto

excitation wavelength and auto confocality focussed by 100X objective lens (spot diameter ~1 μm) in open

atmosphere at room temperature. Cyclic voltammetry (CV) was performed at room temperature of 25 oC using a

multi-potentiostat (Macpile II, Biologic, France) at various potentials of 0.005V–3.0V. EIS was performed on the

Solartron Impedance/gain-phase analyser (SI 1255) with a potentiostat (SI 1268) at room temperature. Galvanostatic

charge-discharge cycling were conducted in the range of 0.005-3.0V vs Li at low current rate of 60 mAhg-1 using Mac

-pile II system (Bio-logic, France). To ensure percolation of the electrolyte to the electrodes, the cells were left to rest

for 12 h before measurement at their OCV.

Results

Figure 1. Galvanostatic cycling plots of TEGO in varying rations of (a) 40:40:20; (b) 65:20:15; (c) 70:10:20; (d) pure

TEGO in 80:20; (e) pure SPC in 80:20; Voltage cycling range=0.005-3.0V; current rate=100mA/g.

Figure 2. Cyclic performance of TEGO in varying rations of (a) 40:40:20; (b) 65:20:15; (c) 70:10:20; (d) pure TEGO in

80:20; (e) pure SPC in 80:20; Voltage cycling range=0.005-3.0V; current rate=100mA/g.



39

Figure 3. Cyclic voltammetry plots of (a) Graphite; (b) Few Layered Graphene (FLG); (c) SPC 80:20; (d) TEGO

80:20; Voltage cycling range=0.005-3.0V; Scan rate, 0.058mV/sec.

Discussion & Conclusion

Through the various characterization techniques and electrochemical tests, we were able to profile ‘Thermally

Exfoliated Graphene Oxide and carbon’ material at various ratios. Exfoliation was done successfully and desired

TEGO structure was obtained. Testing was done to determine which ratio of TEGO-C was optimal. TEGO 60:20:20

and TEGO 70:10:20 showed the most promise among the samples due to low voltage hysteresis, stable capacity

retention as well as boasting capacities higher than that of SPC even when cycled at high current rates of 400mA/g.

The stable capacity of these samples (900mAh/g at 100mA/g and 600mAh/g at 400mA/g) is slightly more than twice

of that of SPC (220mAh/g at 400mA/g current rate and 400mAh/g at 100ma/g current rate). Both showed a good

balance of having high reversible capacities and low capacity fading. However TEGO 60:20:20 shows significantly

lower bulk resistance than TEGO 70:10:20, making it the overall most optimal compound we have synthesized.

Though 70:10:20 performs slightly better than 60:20:20 in GC cycling, the low bulk resistance, high capacity at even

high current rates and stability, coupled with the low synthesis costs as well as scalable manufacturing gives promise

that TEGO 60:20:20 could be an anodic compound that has potential industrial applications in future. With this, we

conclude TEGO 60:20:20 to be the optimal ratio we have found in this project. However, we have also observed in

the compounds that the GC charging and discharging curves makes them a poor suit for current cathodes. Due to

this future research should be focused on obtaining a compound that possess equivalently impressive performance

yet would allow compatibility with commercial cathodes to yield a stable voltage.

Acknowledgements

All student authors contributed equally to this work. Dr Reddy and Mr Petnikota discussed about the initial ideas for

this research with the student authors and Keefe, Amos and Luo Chen worked together to run all the necessary tests

involved in the research. All authors discussed the results and worked together to produce the research paper and

Ms Wong Pui Hong, Dr Reddy, and Mr Petnikota helped to vet through the research paper.

Works Cited/Consulted

[1]: Stankovich, Sasha, et al. "Synthesis of graphene-based nanosheets via chemical reduction of exfoliated graphite

oxide." Carbon 45.7 (2007): 1558-1565.

[2]: Song, Peng, et al. "Synthesis of graphene nanosheets via oxalic acid-induced chemical reduction of exfoliated

graphite oxide." Rsc Advances 2.3 (2012): 1168-1173.

[3]: Aifantis, Katerina E., Stephen A. Hackney, and R. Vasant Kumar, eds. High energy density lithium batteries:

materials, engineering, applications. John Wiley & Sons, 2010.

[4] P Suresh Kumar, R Sahay, V Aravindan, J Sundaramurthy, Wong Chui Ling, V Thavasi, S G Mhaisalkar, S

Madhavi and Seeram Ramakrishna, Free-standing electrospun carbon nanofibres—a high performance anode

material for lithium-ion batteries. J. Phys. D: Appl. Phys. 45 (2012) 265302 (5pp)

[5]: Wakihara, M., Recent developments in lithium ion batteries. Mater. Sci. Eng., R 2001, 33, (4), 109-134.

[6] W. S. Hummers, R. E. Offeman, Journal of the American Chemical Society 1958, 80, 1339.

[7]: Shaikshavali Petnikota & Naresh K. Rotte & Vadali V. S. S. Srikanth & Bhanu S. R. Kota & M. V. Reddy & Kian P.

Loh & B. V. R. Chowdari, Electrochemical studies of few-layered graphene as an anode material for Li ion batteries,

JSolid State Electrochem (2014) 18:941–949 DOI 10.1007/s10008-013-2338-2

[8] RM. Gnanamuthu, Chang Woo Lee, Electrochemical properties of Super P carbon black as an anode active

material for lithium-ion batteries. Materials Chemistry and Physics 130 (2011) 831– 834

contact information

Postal address:

Australian Science and Mathematics School

Flinders University

Sturt Road

BEDFORD PARK SA 5042

Telephone:

+61 8 8201 5686

Facsimile:

+61 8 8201 5685

Email:

[email protected]

Website:

http://www.asms.sa.edu.au

South Australian Department for Education and Child Development trading as South Australian Government Schools, CRICOS Provider Number 00018A

mailto:[email protected]

http://www.asms.sa.edu.au/

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