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CATO. M. GULDBEG THE MATHEMATICIANS AND CHEMIST

Katrina Maalwa Uutoni, group 2. Scientific adviser is Tatyana Tishakova.


Cato Maximillian Guldberg was born in 11 august 1836 and died on the 14 January 1902, was a Norwegian mathematician and a chemist. In 1890 he published what is known now as the Guldberg rule in chemistry which states that: the normal boiling point of a liquid is two third of the critical temperature when measured in absolute scale. He is the one who introduced in chemistry that the law of mass action is a mathematical model that explains and predicts the behaviors of solution in dynamic equilibrium which can describe in two aspects. 1. The equilibrium aspect concerning the composition of a reaction mixture at equilibrium. 2. The kinetic aspect concerning the rate equations for elementary reactions. He recognizes that chemical equilibrium is a dynamic process in which rates of reaction for forward and backward reaction must be equal.

Cato and his brother in law Peter Waange build on Claude Luise Berthollet’s ideas about reversible chemical reaction and proposed the law of mass of action. In medicine regarding this law of mass of action forms the basis of the compartment model of disease spread. In mathematical epidemiology in which a typically human population is divided into two categories of susceptible infected and recovered whereby they are making use of SIR model and Compartment models in epidemiology. Sir model divided into 3 compartments s (susceptible) I (infections) and R (removed) this is a good idea and simple models for many infectious disease including measles, mumps and rubella. Compartment models used in the vaccination program in a presence of a communicable disease one of main task is to eradicate via prevention measure and via establishment of a mass vaccination program. Vaccination program is successful in eradicating the disease in the contrary it will remain endemic although at lower level.



PETER WAAGE

Pungame Magano Ndapewa Amadhila, group 2. Scientific adviser is Tatyana Tishakova.


Peter Waage (29 June 1833- 13 January 1900), the son of a ship’s captain, was a significant Norwegian Chemist and professor at the Royal Fredrick University. Along with his brother in law Cato Maxillian Guldberg, he co-discovered and developed the Law of Mass Action 1864 and 1879.

Law of Mass Action states that “Under similar condition of pressure and temperature the rate at which the substances react is directly proportional to the active mass of the reactants and the rate of reaction is directly proportional to the product of the active masses of the reactant with each concentration raised to power equals to the Stoichiometric coefficient which appears during a balanced chemical reaction.”

In 1854 at University of Christiania, he and Cato M Guldberg together with several other students established a small, informal club whose members met on Saturday afternoons to discuss physical and chemical problems. Waage studied medicine during his first three years at the university but switched to mineralogy and chemistry in 1857. He was awarded the Crown Prince’s Gold medal for his paper. “Development of the theory of the Oxygen- Containing Acid Radicals”, which appeared in 1859, the same year as his book, Outline of Crystallography, coauthored with H. Mohn.

He was appointed Lecturer in Chemistry at the University of Christiania in1861 and in 1866 he was promoted to Professor of the only chair of chemistry at the University. Waage‘s name is intimately linked with that of his friend Guldberg primarily for their joint discovery of the law of mass action.

The fundamental law of chemistry, which today is known to every beginning chemistry student, had several forerunners but the combined efforts of the empirists Waage and the theorist Guldberg were needed to produce the first general exact, mathematical formulations of the role of the amounts of reactants in chemical equilibrium systems.

THE CONTRIBUTION OFAUGUST KEKULÉTO THE DEVELOPMENT OF MODERN CHEMISTRY, MEDICINE AND PHARMACEUTICAL SCIENCE

Lavinia N Ndeilenga, group 2. Scientific adviser is Tatyana Tishakova.


Friedrich August Kekulé, later Friedrich August Kekule vonStradonitz lived from7 September 1829, he was a German organic chemistryespecially in theoretical chemistry, and the principal founder of the theory of chemical structure, from the 1850s until his death.

Kekule’s theory proceeds from the idea of atomic valence, especially thetetra valenceof carbon, the theory of structure provided dramatic new clarity of understanding, and a reliable guide to both analytic and especially synthetic work. As a consequence, the field of organic chemistry developed explosively from this point.

However, most chemists followed Kekulé's lead in pursuing and developing what some have called "classical" structure theory, which was modified after the discovery of electrons and the development of quantum mechanics.

Kekulé's most famous work was on the structure of benzene, in 1865 Kekulé stating that the structure contained a six- rings of carbon atoms with alternating single and double bonds. Three isomers were observed, for which Kekulé proposed structures with the two substituted carbon atoms separated by one, two and three carbon-carbon bonds, later named ortho, Meta, and para isomers respectively.

Kekulé' remained theoretical chemistry till his death on 13 July 1896.

NIKOLAI ZININ

Priscilla-Mary Tetteh, group 2. Scientific adviser is Tatyana Tishakova.


He is known for the so-called Zinin reaction or Zinin reduction in ,which nitro aromates like nitrobenzene are converted to amines by reduction with sodium sulfides. In 1842 Zinin played an important role in identifying aniline.

Zinin’s discovery caused a great interest among European scientists. His reaction of aniline synthesis opened a vast field for aniline applications. The reaction of aromatic amine synthesis by reduction of nitro compounds with hydrogen sulfide bears Zinin’s name. In 1845 Zinin synthesized azoxybenzene, then hydrazobenzene, which used to turn into benzidine in the presence of an acid.

While living in Kazan, Zinin dreamt of moving to St. Petersburg, and after his wife unexpected died of consumption, the scientist’s dream came true. In 1848 Zinin was invited to head the chemistry department in Medical and Surgical Academy in St. Petersburg. The scientist strongly believed that a true medic should know chemistry and physics, since all processes, taking place in an organism, were of chemical and physical origin. Soon Nikolai Zinin got married for the second time. The researcher continued his studies of nitrous compounds. In 1853-1854 Zinin and his colleagues developed a means for saturating black powder with nitroglycerine. In 1858 Zinin was elected the corresponding member of the Academy of Sciences. In 1862 Zinin retired form reading lectures, and two years later Zinin became the academician. In 1868 Nikolai Zinin founded Russian chemical society and headed it.

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