Химия. Экология. Медицина



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DMITRY IVANOVICH MENDELEYEV

Tamiah Uupindi, group 9. Scientific adviser is Tatyana Tishakova.


Russian chemist who developed the periodic classification of the elements, is best known today as the discoverer of the periodic law, Mendeleyev found that, when all the known chemical elements were arranged in order of increasing atomic weight, the resulting table displayed a recurring pattern, or periodicity, of properties within groups of elements. In his version of the periodic table of 1871, he left gaps in places where he believed unknown elements would find their place. He even predicted the likely properties of three of the potential elements. The subsequent proof of many of his predictions within his lifetime brought fame to Mendeleyev as the founder of the periodic law. When Mendeleyev began to compose the chapter on the halogen elements (chlorine and its analogy) at the end of the first volume, he compared the properties of this group of elements to those of the group of alkali metals such as sodium. Within these two groups of dissimilar elements, he discovered similarities in the progression of atomic weights, and he wondered if other groups of elements exhibited similar properties. After studying the alkaline earths, Mendeleyev established that the order of atomic weights could be used not only to arrange the elements within each group but also to arrange the groups themselves. Thus, in his effort to make sense of the extensive knowledge that already existed of the chemical and physical properties of the chemical elements and their compounds, Mendeleyev discovered the periodic law. His newly formulated law was announced before the Russian Chemical Society in March 1869 with the statement “elements arranged according to the value of their atomic weights present a clear periodicity of properties. Mendeleyev law allowed him to build up a systematic table of all the 70 elements then known. He had such faith in the validity of the periodic law that he proposed changes to the generally accepted values for the atomic weight of a few elements and predicted the locations within the table of unknown elements together with their properties. At first the periodic system did not raise interest among chemists. However, with the discovery of the predicted elements, notably gallium in 1875, scandium in 1879, and germanium in 1886, it began to win wide acceptance. Gradually the periodic law and table became the framework for a great part of chemical theory. By the time Mendeleyev died in 1907, he enjoyed international recognition and had received distinctions and awards from many countries.

MRS. MARIE CURIE AND HER CONTRIBUTION TO MODERN CHEMISTRY, MEDICINE AND PHARMACEUTICAL SCIENCE

Stacia Goodlit, group 9. Scientific adviser is Tatyana Tishakova.


Marie Curie is remembered for her discovery of radium and polonium, and her huge contribution to the fight against cancer. Born Marie Sklodowska on November 7, 1867 in Warsaw, Poland, she was the youngest of five children of poor school teachers. She learned to read when she was only four years old and was fascinated by the scientific instruments her father(a teacher) kept at their home, this blossomed into Marie becoming a great chemist.

In Chemistry

Both Marie and Pierre (her husband) began their pioneering work into invisible rays given off by uranium as they worked together investigating radioactivity, a new phenomenon which had recently been discovered by the French Physicist Professor Henry Becquerell and German Physicist Roentgen. Becquerell had shown that the rays were able to pass through solid matter, fog and photographic film and caused air to conduct electricity.

Marie also noticed that samples of a mineral called pitchblende, which contains uranium ore, were a great deal more radioactive than the pure element uranium. Further work convinced her the very large readings she was getting could not be caused by uranium alone - there was something else in the pitchblende. Since nobody had ever found it before, it could only be present in tiny quantities, and it seemed to be very radioactive. Marie was convinced she had found a new chemical element - other scientists doubted her results.

In 1898 the Curie’s discovered the elements polonium and radium. They received the Nobel Prize for Physics in the year 1903 along with Henry Bequerel.

Pierre Curie died in the year 1906 and Marie took over the job Pierre was doing, making her the first lady to teach in Sorbonne. In 1911, Marie received her second Nobel Prize, this time in chemistry for her discovery and isolation of radium and its compounds.

In Medicine and Pharmaceuticals

During WWI, Marie Curie drove ambulances equipped with X-ray equipment to help victims. The International Red Cross made Marie Curie the head of its radiology services, where she and her co-workers would conduct classes for doctors and medical orderlies on how to utilize the new technique. Because of her discoveries much light was shed on using radioactivity in the treatment of cancer. After the war, Marie continued her work as a researcher, teacher and head of a laboratory and received many awards and prizes. Among them were the Ellan Richards Research Prize (1921), the Grand Prix du Marquis d'Argenteuil (1923) and the Cameron Prize from Edinburgh University (1931). She was also the recipient of many honorary degrees from universities around the world. Due to continued exposure to hazardous radioactive elements, Marie became ill and died on July 4th, 1934. She is recognized as one of the greatest researchers as well as an outstanding female scientist.


ATUL KUMAR

Otaigbe Peace Augustine, group 9. Scientific adviser is Tatyana Tishakova.


He is a scientist in the central drug research institute (CDRI) of lucknow, india. His areas of research are organic chemistry, medicinal chemistry and drug design. He has made significant contribution to research on osteoporosis, cancer, tuberculosis, diabetes and other metabolic disorder. He also has a considerable contribution in the areas of organic chemistry particularly in the development of organocatalysed synthesis, biomimetic synthesis, multicomponent reaction, green chemistry, sonochemistry, enzymatic synthesis and diversity oriented synthesis. He has developed a new drug candidate "CENTHANK" CDRI-99-373,(anti-resorptive agent)for the treatment of osteoporosis which is currently in Phase I clinical trials, diabetes and breast cancer, which are in preclinical stages. In the area of medicinal chemistry, he has developed a natural product inspired diversity oriented synthesis of tetrahydroquinoline analogues as antitubercular agents, he has reported pyranocoumarins: a new class of anti-hyperglycemic and anti-dyslipidemic agents, design and synthesis of 1,3-biarylsulfanyl derivatives as new anti-breast cancer agents.

In the area of organic synthesis, he has been involved in the development of new catalysts such as LiposomisedmCPBA (LIP-mCPBA), new solid-supported hypervalent iodine reagents, and the use of human hemoglobin (HbA) and supramolecular carbohydrate molecules as solid catalysts for the synthesis of bioactive molecules. Kumar was the first to demonstrate that single nucleotides have the ability to catalyze organic reactions, and performed biomimetic reductive amination, which is considered as one of the most genuine biomimetric reactions of organic chemistry. This single-nucleotide catalysis has immense impact on many fields of science such as chemistry, biochemistry, and prebiotic studies, especially the RNA world and DNA world hypothesis for understanding the origin of life on Earth. Kumar has reported an efficient and conceptually different approach toward C-H bond activation by using iodine mediated sp3 C-H functionalization for the synthesis of alkyl azarenepyridinium zwitterions.

Kumar has recently demonstrated a new protocol for organic synthesis involving functional ionic liquids and named this new methodology as Functional Ionic Liquid Mediated Synthesis (FILMS).

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