September 2000, Amsterdam - Projects - Latvia
Antons Maslovskis (17)
School: Rezekne Secondary School N6
Hobbies: reading books, listening to music
Career intention: Chemist
E-mail: antonsmav@mail.lv

The use of vegetable dyes as indicators
 Colourless acid and base solutions can be distinguished with the help of indicators as litmus, methyl orange, phenolphthalein and the universal indicator, which are commonly used at schools. We decided to learn which of the plants common in our area could also be used as acid-alkali indicators. So we did research on different acid and base theories and learned that the colour of a substance depends on the structure of its molecules. We continued this study with some practical work. Of the first 32 plants that were tested, the colours of the solutions were transferred on to paper in watercolours. Later we prepared alcoholic extracts from plants and observed colour changes of each dye in five solutions with different pH values. With this,another 10 plants were tested .

Verza Andrejs (17)
School: Valmiera Pargauja gymnasium
Hobbies: Computer sciences, low level and hardware programming, sightseeing, science exhibitions, EU activities
Career intention: Programmer
E-mail: int21h@mauer.lv

"Smart Graphs" program, a graphic method of problem solving
Nowadays, many methods, schemes and theorems are used for solving mathematical problems at middle and high school. All these methods and theorems are very specific and require in-depth knowledge of mathematics. If a more attractive method of solving mathematical problems at school could be discovered, this could mean that problemsolving would become more popular and it could considerably make the teaching of mathematics and other exact sciences more attractive. Looking for this fast, universal and accurate method for solving a wide range of mathematical problems, I started doing research on the graphic method. Of course, this method still has some disadvantages (low performance, inaccuracy), but to eliminate these disadvantages special software has been developed. The software was also tested by students and their recommendations were taken into account. The use of this method together with the newly developed software is a leap forward in teaching mathematics and other exact sciences at school.
http://www.lanet.lv/info/intermat/prg/p166.htm .


Austra Zarina (18)
School: Riga State gymnasium
Hobbies: reading science literature, painting and visiting art galleries
Career intention: chemist or mathematician

The effect of cooling on the visible spectra of gemstones
 I had an opportunity to work in a laboratory where gemstones are tested. I am interested in the way atoms and molecules are packed in crystal structures and what determines the colour of gemstones. Therefore I chose to test how cooling affects the absorption spectra of gemstones. To identify them, a spectroscope is one of the most complete instruments used. However, it has some limitations. Therefore, the main subject of my project was to find a method that would improve the absorption spectrum of a gemstone and reduce the possibility of misinterpretation. The absorption power of a gemstone is dependent on the amount of energy it possesses. The more energy it has, the less it will absorb. Thus the research question of the project was whether cooling a gemstone would increase its absorption power. The absorption spectra of gemstones were measured at temperatures between +25øC and -196øC. The results obtained showed that it is helpful indeed to cool gemstones before measuring their absorption power, because it does increase the absorption power of gemstones. This means that the data obtained from the spectroscope became more understandable and the risk of misinterpretation of data is lower .