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Wednesday, February 11, 2009

SIR C V RAMAN

SIR C V RAMAN
( 1888 - 1970 )
C.V.Raman is the first Nobel Scientist of India. He won Nobel Prize in 1930 in physics for his discovery “Raman Effect”.

Chandrashekara Venkata Raman was born on November 7, 1888 at Tiruchinapalli. He was the son of college teacher. He did his M.A. at Presidency college in Chennai. He took up an administrative job in the Finance Ministry in Kolkatta. His interest in science made him to become a member of the Indian Institute for cultivation of science.

He studied acoustics. He went to London on a lecture tour. On his return journey he was fascinated by the blueness of the sky and sea. He questioned himself why were they blue. He found and concluded that the blueness was due to the scattering of light by water molecules. He wished to prove his theory. He did research in optics. In 1924 he was elected FRS. London for his contribution to optics.

He discovered the scattering of light and later it was named Raman effect. This was discovered on 28 February 1928. He was awarded Nobel Prize. In 1943 he founded his own institute in Bangalore, the Raman Research Institute. He continued his research till his death on November 20, 1970. He worked earlier in Indian Institute of Science, Bangalore.

The Raman effect is important in understanding the molecular structure of chemical compounds. It is the Phenomenon that causes changes in nature of light when it is passed through a transparent medium whether solid, liquid or gaseous.

February 28, annually is being celebrated as National Science day in India.

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ALESSANDRO VOLTA



ALESSANDRO
VOLTA
(1745-1827)

The Italian physicist Alessandro Volta (1745-1827) introduced something new. He found, in 1800, that two metals (separated by solutions capable of conducting an electric charge) could be so arranged that new charge was created as fast as the old charge was carried off along a conducting wire. He had invented the first electric battery and produced an electric current.
Italian physicist; physics professor; experimented with electrical forces; invented first practical battery using cells made from two kinds of metals; this verified his theory of differing electrical potentials for unlike metals; electric potential difference is known as voltage and its unit is the Volt (V).

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LUDWIG BOLTZMAN



LUDWIG BOLTZMAN
( 1844 - 1906 )

The Austrian physicist Ludwig Boltzmann (1844-1906) had analyzed the behavior of gases on the assumption that they were an assemblage of a vast number of randomly moving particles (the kinetic theory of gases). They were able to derive Boyle's law on this basis, provided they made two further assumptions;
that there were no attractive forces between gas molecules.
that the gas molecules were of zero size.
Gases that fulfill these assumptions are perfect gases.
Neither assumption is quite correct. There are small attractions between gas molecules, and though these molecules are exceedingly small, their size is not zero. No actual gas is quite "perfect", therefore, although hydrogen and the later-discovered helium come close.

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MADAM CURIE

MADAM CURIE
( 1867 - 1934 )

A lady scientist Marie Curie who discovered Radium was born at Warsaw in Poland. Her name was Marie-Sklodowska. She married Pierre Curie who was also a scientist and became famous as Madam Curie.

Madam Curie was fortunate. Both her parents were teachers. Her childhood was spent in studies and at 16. She came out of highschool with a gold medal. In 1891 she went to Paris and obtained science degree from Sakhan university. There she fell in love with Pierre and they got married.

Madam curie started her carrer in science with Prof.Henri Becquerel, the discoverer of radio activity. Both husband and wife did research. Their mutual interest was in magnetism. After Becquerel discovered that Uranium salts emitted rays that resembled X-rays, the Curies set out to discover whether there were other substances that emitted such rays. They finally managed to isolate the radium metal in 1910. to do this research the Curie couple requested the government of Bohomia to donate 10,000 kgs. Of uranium pitchblende free of cost. It was found in plenty there. They gotit free of cost. For months together the couple did a lot of hard work to extract radium from it. For this work Marie Curie, Pierre Curie and Becquerel received the Nobel prizefor physics in 1903.

In 1911 Madam Curie wa awarded the Nobel prize in chemistry for her work on the isolation of radium and polonium and for the study of the chemical properties of these elements.

Soon after the discovery, radium was found effective in the treatment of cancer. The Curies had a daughter and she was Irene curie who married Fredric Juliot. Both Irene and Juliot were scientist and they were awended Nobel Prize in 1935 for chemistry. They synthesized artificial radio active substances.

In 1906 Pierre died in a road accident. Marie Curie established Curie Insitute of Radium. An element ‘Curium’ is named after her and a unit of radio activity ‘Curie’ have been named in her honour.

Throughout her life Marie Curie was exposed to radio active substances. She died of leukemia and blood cancer on July 4, 1934.

The life of Marie and Pierre Curie shows how they were devoted to science. The entire Curie family worked for the benefit of mankind.

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JONS JAKOBS BERZELIUS



JONS JAKOBS
BERZELIUS
(1779-1848)

Swedish physician and chemist; discovered cerium, selenium, lithium, silicon, titanium and thorium; coined the terms "isomer" and "isomerism"; published a revised version of the periodic table with atom weights very close to today's table (1828); proposed system of elemental symbols and chemical notation.

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KANADA

KANADA
( 600 B.C.)

Vaisesika Sutras are a blend of science, philosophy and religion. These sutras or Aphorisms were propounded by the Indian scientist Kanada.

The essence of these Sutras is the atomic theory of matter.

Kanada said: “Everything is made up of ‘Paramanu’. When matter is divided, then further divided, till further no division is possible, the remaining indivisible entity is Paramanu. This does not exist in a free state nor can it be sensed through any human organ. It is indestructible.” Paramanu is atom. The name is given by Kanada.

Kanada, the scientist identified different or a variety of Paramanus. He said that each paramanu has a specific property which is same as the class of substance to which it belongs to. This peculiar property has made to be called vaisesika sutra.

He also discovered : If two paramanu belonging to one class of substance combined a devinuka is produced. This devinuka or binary molecule has the properties similar to those of the two original paramanu.

Paramanu or atom belonging to different classes of substance could also combine in large numbers., “because of the peculiarily or speciality of paramanu all things seen in the world are formed” he said.

Heat is the root cause for a change. When you heat a substance there will be a change. Due to heat mango ripens. Due to heat the earthen pot blackens. Due to heat water boils. So Kanada claimed that heat was responsible for any change.

Kanada was a saint. He was in a hermitage. National Aeronautical Laboratory in Bangalore runs a science magazine in Kanada’s name. The magazine is Kanada.

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JOSEPH LISTER

JOSEPH LISTER
( 1827 - 1912)

Lord Joseph Lister was a British surgeon. He received his medical degree from university college, London. He was professor of surgery at Edinburg and later at King’s college hospital.

Lister studied Louis Pasteur’s work on micro organisms in fermentation process and thought that minute germs also cause infections. He developed techniques of antisceptic surgery. He developed techniques of antisceptic surgery. He established the British Institute of preventive medicine in 1893. It was called Lister institute after his death in 1912.

Lister involved Carbolic acid dressings, cleansing instruments and ligatures in carbolic solutions. Carbolic acid or phenol is a disinfectant that prevent all the post operative problems of infection.

Lister was the first physician to be elevated to the House of Lords. The honour was bestowed upon him by Queen Victoria. She was a patient of Lister earlier.

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JOHN DALTON



JOHN DALTON
(1766-1844)

An English chemist, John Dalton (1766-1844), went through this chain of reasoning. In this, he was greatly aided by a discovery he made. Two elements, he found, might, after all, combine in more than one set of proportions, but in so doing they exhibited a wide variation of combining proportions and different compound was formed for each variation

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JOHN NAPIER

JOHN NAPIER
( 1550 - 1617 )

Today we are all living in computer age. Logarithms are not much in vogue. But at one time even in 20th century for difficult mathematical calculations logarithms were the base. The concept of Logarithms was introduced by the British mathematician John Napier.

Napier was born in 1550 at Merchiston castle near Edinburgh. He entered the university of St.Andrews at the age of 13. But he left it early without obtaining a degree. He returned to his native after he traveled abroad. He married in 1572 but his wife died in 1579. Again he married.

In 1593 he wrote a book on the Church of Rome. In the book he had boldly said that the Popes of Church would destroy the world between 1688 and 1700. The book saw twenty one editions of which ten editions were sold during his life time.

He invented Napier Rod an instrument used for addition, subtraction and calculating, square roots. In 1593 he started working on logarithms. He prepared tables of natural logarithms; that is, logarithms to base ‘e’. These were later modified by Henry Briggs by using the number 10 as the base.

Napier did research on trigonometry. He contributed to the development of spherical trigonometry.

Description of Marvelons Canon of Logarithms (1614) and construction of the Marvelons Canon of logarithms (1620) are the two treatises published by Napier. Logarithm tables help students a method for speedy calculation.

Napier died on 4 April 1617 in his native place.

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JAMES CHADURICK

JAMES CHADURICK
(1891 - 1974)

Chadurick was the discoverer of Neutron. He found that when Beryllium was exposed to bombardment by Alpha particles, it released an unknown radiation. He interpreted this radiation as being composed of particles of mass approximately equal to that of the PROTON but having no charge, he called neutrons. Chadurick was a British physicist. He won Nobel prize in physics for his discovery of the NEUTRON in 1935.

The study of neutrons led the discovery of Nuclear Fission and the first Nuclear reactor.

Neutron is an elementrary particle that is a part of the atoms of all elements except normal hydrogen. It is present in the nucleus of the atom along with other particle Proton.

Reactor is an assembly in which nuclear Fission can be carried out in a controlled manner.

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Tuesday, February 10, 2009

CARL WILLIAM SCHEELE



CARL WILLIAM SCHEELE
( 1742 - 1786)


Swedish scientist, self-educated. He used to work as an assistant in pharmacies and showed a talent in chemistry from a very young age. In spite an offer made to him to study in London or Berlin, he operated a pharmacy in kipping where he spend the rest of his life and made all his important inventions. He was especially interest on chemical analysis and worked particularly with the chemical reactions between silver nitrate and sunlight, therefore making a break through in the chemistry of photography. The records from his experiments were of a great importance for the next generations of scientists.

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UGLICHNO MARCONI

UGLICHNO MARCONI
( 1874 - 1937)

Marconi is the inventor of wireless telegraphy and radio. He was born at Bologna in Italy on 25 April 1874. He was encouraged by his mother to do research. Marconi was conducting experiments in his father’s estate after he studied physics in a technical school. He showed interest in sending telegraphic messages without the help of wire. He had come to understand that Heirich Hertz had believed that radio waves could be used to carry messages. Marconi sent wireless messages. He positioned an electric bell in between many instruments in one corner of the room. He went to the other corner of the room and pressed the Morse Key. (Samuel Morse. The inventor of telegraphy). To his surprise the electric bell placed at a distance of 30 feet rang. The ringing of the bell with the radio waves was possible. In an another instance, he placed his self made transmitter on one side of a hill and received the message on the other side. This experiment made him to send messages to long distance also. By 1897 he had succeeded in rado communication over a distance 20 kilometres. He established the Marconi company in 1897. In 1899, He transmitted a radio signal across the English channel a distance of nearly 50 kilometres.

Marconi’s invention made radio broadcasting to begin in England on 14th February 1922. Radio is the term applied to methods of signaling through space, without connecting wires, by means of electromagnetic waves generated by high frequency alternating current.

Marconi was made the president of the Royal Italian Academy in 1930. Several changes took place in radio communication after its invention by Marconi. He lived to see all of them. He died on 20 July, 1937 in Rome. In 1909 Marconi received the Nobel Prize for his invention.

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HOMI JEHANGHIR BHABHA

HOMI JEHANGHIR BHABHA
(1909 - 1966 )

Famous Indian scientist who was instrumental in establishing the Atomic Energy commission in India. Bhabha was born on October 30, 1909 into a wealthy Parsi family. Even as a child he showed interest in science. His father wanted bhabha to become an engineer and sent him abroad for higher studies. But bhabha’s interest like Enrico Fermi and the Austrian Physicist Wolfgang Pauli.

Bhabha made research on cosmic rays. He joined the Indian Institute of Science, Bangalore. Cosmic rays are fast moving, extremely small particles coming from outer space. They were detected first by V.F.Fless in 1912. Cosmic rays are atomic nuclei accelerated to very high energies. They are highly penetrating. When these rays enter the earth’s atmosphere they collide with the atoms in the air and produce showers of electrons. Along with W.Heitler, a German physicist Bhabha solved the mystery surrounding these rays. Bhabha recognized the presence of a new nuclear particle in the showers which he called ‘meson’. In 1940 he retuned to India from England as second world war broke. He was elected fellow of the royal society for his contributions relating to cosmic rays and quantum mechanics.

Due to the concerted efforts of Bhabha Tata institute of fundamental research was set up. He set up this institute with the encouragement of the then. Prime Minister of India Jawaharlal Nehru a prestigious centre for research in nuclear physics which later came to be known as the Bhabha Atomic research centre. Bhabha’s interest was to make India, a nuclear powered country. Under his guidance three atomic reactors Apsara, Cirus and Zerlina were built. He was also responsible for the construction of the country’s first atomic poer station at Tarapur. The station began in 1963. Two years later a plutonium plant was installed. He also encouraged research electronics, space science, radio astronomy and microbiology. The radio telescope at Ooty is one of his creations. He was of the attitude tha atom is for peace. He was one of the eminent members of the ‘atom for peace’ conference. It is on 24 January 1966 Bhabha died in an aircrash on his way to attend an international conference. He was 57.

Bhabha was a person of varied interests. He spend his spare time painting and writing poetry. He was fond of western classical music. He was a first class painter. His pencil sketches are famous. Few paintings of Bhabha are still preserved in British art galleries.

Homi Bhabha was a bachelor. He was once asked if he was married. ‘Yes’ he replied and then siling he added, ‘to creativity.’

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HIPPOCRATES

HIPPOCRATES (B.C.)

Today the doctors who came out of the universities take an oath that they serve mankind. The oath they take is in the name of Hippocrates, the father of Medicine. The oath runs as follows:
“Into whatever houses I enter, I enter to help the sick; If anyone shows interest in learning this process of treatment for implementation I shall offer guidance free of cost. My education is law abiding.”

Hippocrates was born on the Greek Island of COS. He was the son of a priest. In those days the Greeks believed that the people suffered from diseases because of the displeasure of Gods and the sick people had to go to the temple and accept ointment and medicines from the priests only. Hippocrates when he was brought up did not believe in this mode of healing of the patients. He believed only in the facts ascertained by experiments and observations in treating patients suffering from diseases. He said:”diseases are not God sent to be taken back by Gods”. He also said that every disease had its own explanatory cause and if this element of physical cause of the disease is detected they may be treated to cure it. Nothing is achieved by sleeping in temples and offering prayers.

According to Hippocrates nature is the best healer. In the treatment of disease nature plays an important role. In the maintenance of good health he advocated these facts namely (1) Creation of healthy or sick free atmosphere (2) Development of personal or individual habits.


Hippocrates depended upon hydro therapy. He used a mixture of hot and cold waters for the treatment of fever, wounds etc., He demonstrated as to how cold water bath would give comfort to man, retaining the body temperature also. He preferred Sub bath for TB patients. He said to them to drink fresh and good milk.

Hippocrates became successful because of his scientific approach. Experimentation, observation and inference. He detected the causes and the symptoms of the disease he cured. He told doctors to examine the patients carefully and note down the symptoms of the diseases and begin the treatment.

Hippocrates’s Aphorisms are popular.

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WILLIAM GILBERT



WILLIAM GILBERT
( 1540-1603 )

English physician; known for his early studies on electricity and magnetism. His De magnete (1600) propounded the theory that the earth was a giant lodestone with north and south magnetic poles. His theory that the earth exerted a magnetic influence throughout the solar system was a precursor to the modern conception of gravity as an attracting force between masses. Gilbert was among the first to divide substances into electrics (spar, glass, amber) and nonelectrics.
Centuries later, the English physicist William
Gilbert (1540-1603) was able to show that it was not amber alone that acted so, but that a number of other substances as well gained an attracting power when rubbed. About 1600, he suggested that substances of this sort be called "electrics", from the Greek word for amber.
As a result, a substance that gains such a power, through rubbing or otherwise, is said to carry an electric charge, or to contain electricity.

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HEINRICH RUDOLPH HERTZ

HEINRICH RUDOLPH HERTZ
( 1857 - 1894)

Hertz was a German Scientist. He opened the way for the development of radio. Television and RADAR with his discovery of electromagnetic waves.

Hertz was born on 22 February 1857 at Hamberg into a rich family. He studied architecture and mechanical engeneering. But he developed interest in science and research. He worked under Herman Won Helm Holt in Berlin university. He got his degree in 1880. He went to Keel as a teacher where he studied electro magnetism. Manwell had opined that electric and magnetic waves can be transmitted as light waves. Hertz desired to prove this statement. He made transmitters to transmit electro magnetic waves and receivers to receive them. This has helped today’s Radio, TV and Radar.

Hertz used a rapidly oscillating electric spark to produce waves of ultra high frequency. He showed that these waves caused similar electrical oscillations in a distant wire loop. He also showed that light waves and electromagnetic waves were identical thus proving James C.Maxwell’s theoretical conclusions.

Hertz determined the wave length. He confirmed that the speed of electro magnetic waves is equal to the speed of the light waves. It is 300 million metres.

Hertz is the SI unit of frequency of a periodic phenomenon. It is the number of repetitions of a periodic phenomenon per second. It is named after the scientist Heinrich Hertz. The symbol is Hz. Eg: the frequency of aleternating current used in India is 50 Hz.

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HARAGOBIND KHURANA

HARAGOBIND KHURANA
(B.1922)

Haragobind Khurana, the Indian Scientist is the third Indian who won Nobel Prize in the field of physiology and medicine in 1968. He shared it with Robert W.Holley and Marshall W.Nirenberg for interpretation of the genetic code and its function in protein synthesis.

Khurana was born on Jan 2, 1922 at Rajpur in Punjab. He was the son of a village tax collector. The family was illiterate in the entire village. But khurana studied well and passed degree examination from Lahore college. He took post graduate degree in chemistry in 1945 from Punjab university. Then he went to Manchester University for higher studies. He obtained his doctorate degree in 1948. On his return to India, he was disappointed. He could not get a job for many months. He went back to England and worked with Nobel Laureate Sir Alexander Todd at Cambridge University. In 1952 he went to Canada and married the daughter of M.P.Switzerland.

Khurana helped to decipher the Genetic Code by recreating Synthetically each of the 64 possible triplets of DNA (De onyribo nucleic acid) which work in combination as instructions for the protein synthesizing mechanism of the cell. He succeeded in Synthesizing the first wholly artificial gene. It was E.coli or Escherichia coli.

E.Coli is a bacteria that lives in the intestines of human beings and animals. Khorana and his team worked to build a gene of this organism. Piece by Piece they built up the 207 genes of this bacteria. In August 1976, the man made gene was inserted into E.Coli which began to work like the natural gene. Khorana’s achievements made available a technique to change genes and observe the results of those changes.

Khorana is the recipient of many awards. To mention a few he has been given Merch award of the chemical institute of Canada, Gold medal of the professional institute of Canadian public service, Dannie Heineman prize, Lasker foundation award and Louis Horutiz prize.

Khorana has published more than 300 papers on genetic research. He is Padma Bhushan.

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HALDANE J.B.S.

HALDANE J.B.S.
(1892 - 1964 )

Haldane was an English born Indian biologist. He was born on November 5, 1892 at oxford. Even as a child he was different from other children. When he was a two year old he was immitating the faces of various dogs. He was experimenting upon himself. His father was a noted physiologist. He helped his father in experiments. He learnt many languages and read books on various subjects. He was sharp in mathematics which brought him Russell prize at 16. He was taught at Cambridge and at university college in London. He did reaserch in Biochemistry. In 1925 he showed interest in genetics and elected the fellow of Royal Society in 1932. He was made professor of Genetics in University college, London.

He decided to emigrate to India in 1957 and got citizenship in 1961. He didn’t go back to England. He made contributions to several diverse subjects such as medicine, evolution, physiology, genetics, biochemistry, mathematics and cosmology. He estimated the rate of mutation of a human gene. He said that mutation, the sudden change in a gene occurs once for every 50,000 people per generation. He wrote two books titled ‘Enzymes’ (1930) and ‘The causes of Evolution’ (1932). They are scientific classics. His discoveries in biochemistry have been known as laws of enzyme chemistry.

He did research in physiology also. He found how chemicals, CO2 gas, ice cold temperature affect breath. He discovered cure for tetanus and convulsions. His book ‘My friend Mr.Losakey’ is specially written for children.

While in India, he was inspired by Hindu philosophy and the principle of nonviolence. He liked to wear dhoti and kurta. He was appointed a professor at the Indian statistical institute, Kolkata. He was director, Genetics and Biometry laboratory, Bhuvaneshwar. He died of cancer at Bhuvaneshwar at the age of 71. Even at his death bed he was cheerful and wrote a poem ‘Cancer’s a Funny Thing’. He had made research on colour blindness and haemophilia.

John burdon Sanderson Haldane, Popularised science during his life time. He was also a social worker.

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VON LIEBIG



VON LIEBIG
(1803-1873)

German chemist, Justus von Liebig (1803-1873) who, by 1831, could obtain fairly reliable empirical formulas as a result. (Liebig was one of the great chemistry teachers of all time. He taught at the University of Giessen, where he established the first real laboratory course in chemistry. Numerous chemists studied with him and learned laboratory procedures from him. Liebig was one of the influences making chemistry, in which France had been pre-eminent in the eighteenth century, almost a German monopoly in the nineteenth century.) Soon afterward, in 1833, the French chemist Jean Baptiste Andre Dumas (1800-1884) devised a modification of the method, one which allowed the chemist to collect nitrogen also among the products of combustion. In this way one could determine the proportions of nitrogen in an organic substance.

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IVAN PETROVICH PAVLOV

IVAN PETROVICH PAVLOV
( 1849 - 1936)

Pavlov was a Russian physiologist who won the 1904 Nobel prize in physiology or medicine for unraveling the mechanism of the digestive process and his work provided psychology with a more objective methodology and led to new methods of treating mental illness. Using dogs for experiments he established the idea of conditioned reflexes which for example, makes a pre conditioned dog salivate merely on hearing a bell, in expectation of food though it may not be actually there.

Pavlov demonstrated his theory of conditioned reflex in 1901. In 1920 he extended his theory of animal behaviour to human psychology. He invented new techniques in his work. He provided a foundation for modern gas troenterology and behaviourist school of psychology.

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HIPPOLYTE BAYARD



HIPPOLYTE BAYARD
( 1807 - 1887)


The most unfortunate from the pioneers of photography. Discovered one direct positive photographic method. He was the first person to hold a photographic exhibition (for humanitarian reasons) and the first who combined two negatives to created one print (called Combination Printing). As a civil servant and with five hundred franks that received as financial help from Arago for improving his method, prevented him from presenting the discovery of photography at the French Academy of Sciences.

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GAY LUSSAC

GAY LUSSAC
( 1778 - 1850 )

Joseph Louis Gay Lussac was a French chemist and physicist. He stated Gas laws.
Gay Lussac was a physics lecturer at Sorbonne and he became a professor at the Ecole Polytechnique. In 1802 he reformulated Charles Law of thermal expansion of gases.

Charle’s law states that the volume of a given mass of gas at constant pressure is directly proportional to the absolute thermodynamic temperature; equivalently all gases have the same coefficient of expansion at constant pressure.

Gay Lussac’s Law states that when gases react they do so in volume which bear a somple ratio to one another and to the volume of the resulting substances in the gaseous state, all volumes being measured at the same temperature and pressure. That is the gases combine chemically in simple proportions by volume.

Gay Lussac also obtained sodium and potassium in 1808 and 1815. He was the first to obtain an acid without oxygen or anhydrous prussic acid. He developed new methods of volumetric analysis.

Jean Baptiste Biot was Gay Lussac’s friend. Both were physicists. They once made a daring balloon flight which took them to more than 7000 metres. At an elevation of about 7016 metres the balloon stopped going high and Gay Lussac threw all kinds of things off from the ballon. It is said that the people who were peasants who saw them believed that the objects were throuwn from heaven.

Gay Lussac proposed the law of combining volumes in 1809 which states that gases form compoiunds with each other in simple, definite proportions which can be expressed by the formula of the compounds.

Eg: Formula for water – H2O shows that it is formed of 2 parts of hydrogen and one of Oxygen.

Gay Lussac also improved processes for making sulphurc and oxalic acid in industry.

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GREGOR JOHANN MENDEL

GREGOR JOHANN MENDEL
(1822 - 1884)

Mendal was the father of modern genetics. He was an Austrian monk. He studied science at Vienna University. He taught natural sciences at the monastery school at Brunn (Bruno in Czech). It was a technical high school.

Mendal was fond of nature. He loved flora and fauna. He cross bred different varieties of Pea Plants and studied different characteristics like colour, height and seed shape. He observed that each characteristic was passed on to the next generation independently of the other characteristics and various characteristics in the parent plants recombined randomly in their off springs. He conducted breeding experiments for about nine years to explain the mechanism of inheritance. This led him to formulate his laws. According to him the individual characteristics are determined by inherited factors which are governed by two laws namely the Law of Seggregation and the Law of Independent Assortment.

Law of Seggregation says that each hereditary characteristic is controlled by two factors which separate and pass into separate reproductive cells. Their individualities are maintained.

Law of independent assortment states that pairs of factors separate independently of each other when reproductive cells are formed.

The factors regarded for the expression of special nature have been identified as genes. The genes are transferred from the parents to their children during reproduction. There may be few exceptions. That is they differ in some respect or the other which is called variation. Both the genetics and variation are the basis for the evolution of the species.

Mendel presented his work at the meeting of Brunn Natural Science Society in 1865. But this was not much attended at that time. However his work was rediscovered in 1901. Mendel spent his last few years of his life experimenting with bees. He had the Apiary surrounding the monastery. He died in the year 1884.

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WILLIAM HENRY FOX TALBOT



WILLIAM HENRY
FOX TALBOT
( 1800 - 1877)

Professor of literature, egyptologist, mathematician, classicist, physicist, transcriber of chaldean cuneiform texts, who with his inventions on photography created the foundations for the development of this art and science for the next one hundred and fifty years. After a trip to Italy, where he used camera lucida for complicated designs, decided to discover a more practical and easy way to record images. He succeeded quite early, in 1835 by creating the first negative. His greatest discovery the negative process, minimizes exposure time considerably compared to passed methods. With the help and guidance of his friend Herschel achieves extraordinary results, which announces on January 1839 at the Royal Society and since then English and French argue on who first announced the discovery of photography.

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SIR FREDRICK GRANT BANTING

SIR FREDRICK GRANT BANTING
( 1891 - 1941 )

Banting was the Canadian physician. He was a medicinal scientist. He extracted the insulin hormone from the Pancreas. Insulin is a protein hormone which is produced by the islets of Langerhans of the Pancreas. It is widely used in the treatment of diabetes mellitus. Banting’s research made it possible to prolong the lives of the victims of diabetes. Otherwise they were facing death as the level of glucose accumulation in the blood stream was to be higher. Banting isolated insulin in a fantastic way. His assistant was Best. Both tied the Pancreatic duets of several dogs for a period of seven weeks, after which the Pancreas crumbled up and were functionless as digestive organs. The is bets of Langerhans remained intact and a solution was extracted from these cells. Banting and Best did their work in the laboratory of John J.R. Macleod at the university of Toronto. Macleod didn’t participate in the work. But still Nobel Prize in physiology and medicine was awarded to both in 1923. They shared where as Best didn’t get anything. But Banting sent half of the award amount to his assistant charles H. Best. They demonstrated the role of insulin in controlling the blood sugar levels. Insulin injection results promptly in decline in blood glucose concentration and an increase in formation of products derived from glucose.

Banting died in 1941.

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FREDRICK WOHLER

FREDRICK WOHLER
(1800 - 1882)

German chemist Fredrick Wohler was the first to synthesize an organic compound ureas, from an inorganic chemical. The synthesis destroyed the belief that organic substances could only be formed in living plants or animals.

Wohler was born in July 1800 in a tiny village near Frank Fortommaine. His father guided him well. Wholer showed keen interst in chemistry. He did many experiments using voltaic cells. He joined Marberg university to study medicine at 20. he examined the impure objects produced in the human body to turn out as urine. He got his medical degree from Hidelberg University. But he did research in chemistry as per the suggestion made by his chemistry professor. He went to Stockholm and worked under chemist Bezelius. He made a compound silver cyanate using nitrogen, carbon, oxygen and silver. Wohler found another scientist Justace Livebig who made the same compound whose formula remained same. But these two same compounds had different properties and behaving differently. These two scientists became close friends.

Wohler made potassium cyanate and when it was mixed with ammonium sulphate needle shaped urea or ammonium cyanate crystals were produced. This was a new discovery. Till such time no such organic chemical was made. It was a mile stone in the development of science.

Wohler also developed a process for preparing metallic aluminium, and isolated beryllium and yttrium. He died in 1882.

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HERCULES FLORENCE


HERCULES
FLORENCE
( 1804 - 1879)
Few details are known for his life. In 1824 goes to Brazil and takes part in a scientific mission at the Amazon, whre he becomes preoccupied with the idea of recording images from his trip. From 1830 devotes himself to research and experimentation for photography. The above gives Brazil the ability to claim that is one of the places in the world, where photography was found.

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EUCLID

EUCLID

(300 B.C.)

Euclid is called the father of geometry. He was the Greek Mathematician and wrote the book ‘Elements’ the oldest mathematical work. The first printed version of Elements appeared in 1482 in Latin and the first English translation was published in 1570. It was used as a reference book until 20th century and regarded as a model of logical reasoning. It is understood that Euclid was educated in plato’s academy. He is supposed to have been taught in Alexandria.

‘Elements’ is a set of thirteen valumes which contain information about point, lines, circles, triangles, ratio and proportions, solid geometry and geometrical figures like sphere, pyramid etc., Euclidian geometry have become famous all over the world.

Euclid said, “There is no royal road to learning. In geometry all must go the same away.”

Once Euclid was teaching geometry to students. A student stood up and asked him. “Can you tell me just what is the practical advantage in studying geometry?”

Euclid didn’t answer him. He called his servant and said, “Give this gentleman some money. He cannot learn without money.”

Once few teacher asked Euclid to tell how to measure the height of a great pyramid as there is no way. But Euclid smiled. He measured the length of the Pyramid’s shadow at the precise time when the length of his shadow was exactly equal to his height.

Euclid said that is it impossible to become a theoretical researcher if one does not practice geometry. The other books written by Euclid are data, division of figures, phenomenon, surface, lociprisms, and cones common lessons in music.

In the middle of 19th century new methods different from that of Euclid were introduced and new books were published. They are called non Eucledian methods. David Hilbert was the pioneer of this new method in 1899. Albert Einstein took help from Euclidian geometry to develop his theory of relativity. He said that two events in his youth were important of which one is the study of Euclidian geometry at the age of 12.

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ERNEST LORD RUTHERFORD

ERNEST LORD RUTHERFORD

( 1871 - 1937)

Rutherford gave us the description of an atom. He showed that there is a small part inside an atom. He developed atomic theory resembling description of a solar system. He raid that an atom is composed of a heavy nucleus in the center, with a positive charge of electricity and negatively charged electrons surrounding it.

Rutherfor was born on August 30, 1871 in Newzealand. He was educated in Newzealand and pursued his higher studies at Trinity college, Cambridge University.

He worked under physicist J.J.Thomson. In 1898 he became the professor of physic at Mc.Gill university in Canada and studied radioactivew disintegration. In Cavendish laboratory he deiscovered that there were different kinds of rays given off by radioactive substances. He called them alpha and beta rays.

He distinguished them and showed that radio activity involved natural transmutation of rado active elements. The alpha rays helped him to decide the structure of an atom. For his work on radio active substances he was awarded the Nobel prize for chemistry in 1908. in 1917 he successfully bombarded nitrogen with alpha particles, changing the atoms to oxygen atoms and he became the first person to change one metal into another. He was appointed Director of the Cavendish laboratory in 1919. Rutherford named hydrogen nucleur ‘Proton’. He was the President of the Royal Society from 1925 to 1930.

He died on 19 October 1937 at Cambridge in England. He was buried in West Minister Abbey. The element Rutherfordium whose atomic number is 104 is named after him in his memory. Rutherford’s conclusion that an atom consist of a small positively charged nuclears became the basis for Wiel’s Bohr’s work on the atomic structure. Wiel’s Bohr and Rutherford were intimate friends.

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ENRICO FERMI

ENRICO FERMI

( 1901 - 1954)

Fermi, the Italian – American Physicist was one of the pioneers of the nuclear age. He was born on 26, September 1901 in Rome. At the age of 21, he obtained his Ph.D. in the fields of X-rays from the university of Pisa. In 1926 he made his first major contribution to physics with his work on the statistical behavious of a monoatomic gas, later called Fermi gas. In 1927 he was appointed as a lecturer of physics in Rome University. Ten years of research he discovered that when a element is bombarded by a slow moving neutron, it becomes adioactive and starts emitting radiations. The result is, one element charges into another element. In 1933 he discovered a neutral particle called neutrino. He produced eightly new artificial nuclei by neutron bombardment.

Fermi went to USA on an invitation to speak at Columbia University. Thereafter he remained there only. In 1938 he was awarded Nobel Prize in Physics. He became a professor in the Columbia University in 1939 and a US citizen in 1944. he designed the first nuclear reactor in Chicago. The reactor generated the energy by nuclear fission. He was instrumental in developing of an atombomb during the second world war.

Fermi joined Chicago University after second world war. The institute of nuclear studies there was name after him. In 1944 – 45 he had served as Associate Director of the Los Alamos Laboraory in New Mexico. He received the medal of merit in 1946. He was the recipient of the first annual award of the Atomic energy commission in 1954. 100th element fermium was named after him. An award called Fermi award was instituted in his honour and is awarded for outstanding work in Science in America.

Fermi died on 28 Nov, 1954 in Chicago.

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EDWARD JENNER

EDWARD JENNER

(1749 – 1823)

Today we have number of life saving Vaccines for several diseases. These vaccines are produced on Jenner’s theory. Edward Jenner was a British Physician who established the practice of vaccination. He is the discoverer of small pox Vacination. Small pox is fully eradicated. This was a dreadful disease 250 years ago. Usually people suffering from it died. Those who survived would have become ugly or blind. Jenner found vaccination for prevention of small pox.

Jenner was born on May 17, 1749 at Berkely. He studied medical science, while he under went training under a surgeon, he observed in 1766 milk maids once ‘infected with cow pox developed a life long immunity to small pox. Cow pox is a disease of cows. One who milks a cow suffering from this disease can get it. After completing his training Jenner began his medical practice in 1773. he ascertained that cow pox protects from small pox only when cow pox is introduced at a particular stage. In may 1796, he inoculated an 8 year old boy with fulid from cowpox listers. Two months later, he inoculated the boy with live active small pox virus but the disease did not follow. Nobody took Jenner’s experiment seriously. Few practioners believed that cowpox and small pox were two different diseases some people made adverse remarks stating that injecting a fluid from a cow into the human blood is a dreadful act. But Jenner ignored them. Actually, Jenner’s was the first successful immunizing procedure against any disease. Jenner won world wide admiration for his discovery. He was awarded by British parliament. He also made further discoveries about animals. But he devoted his whole life on fighting against small pox.

Jenner died in 1823 at Berkely, until 1881, the cow pox vaccine was the only inoculating material available. To day innumerable vaccines have been developed and they are being made effective. The principle of vaccine has been extended to prevent fertility.

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AMEDEO AVOGARO

AMEDEO
AVOGADRO
(1776 - 1856 )
Amedeo Avogadro was an Italian scientist born in the Kingdom of Sardinia ad Piedmont, most noted for his contributions to the theory of molarity and molecular weight. He was born on August 9, 1776. The number of molecules in one mole is called Avogadro’s number is honor of him, as is Avogadro’s law.

Avogadro’s law implies that the relationship occurring between the weights of same volumes of different gases (at the same temperature and pressure) corresponds to the relationship between respective molecular weights. Hence, relative molecular masses can be calculated from the masses of gas samples.

Avogadro developed this hypothesis after Joseph Louis Gay-Lussac had published in 1808 his law on volumes (and combining gases). The greatest difficulty Avogadro had to resolve was the huge confusion at theat time regarding atoms and molecules ? one of most important contributions of Avogadro’s work was clearly distinguishing one from the other, admitting that simple particules too could be composed of molecules, and that these are composed of atoms.

In 1820 he became a professor of Turin’s university. With suspicious enthusiasm, he took part in political revolutionary movements of 1821 (against the king of Sardinia), so two years later he was removed from his position (or as it was officially declared, the university was very glad to allow this interesting scientist to take a rest from heavy teaching duties, in order to be able to give a better attention to his researches). Well before this, following the increasing attention to lus works, Avogadro had been recalled at Turin university in 1833, where he taught for another twenty years.

In honor of Avogadro’s contributions to the theory of molarity and molecular weights, the numbr of molecules in one mole was renamed Avogadro’s number.

But his own time, Avogadro’s principle was seriously neglected. Historians of science have several theories as to why this should be so, as Avogadro was a respected scientist during his life. But the real reason is probably more prosaic. In the clannish world of scientific discovery, it pays to be at the center of the action. Avogadro was by this time a professor, and chairman, of physical chemistry at the University of Turin. But in Italy far away from the major science centers of England, Germany, France or even Sweden. He never got to rub shoulders with the “great ones” of his day, so his ideas did not receive the credit they deserved.

He was a professor until his retirement at the age of 74. He died on July 9th, 1856.

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Monday, February 9, 2009

William Crookes

WILLIAM CROOKES
1832-1919

English chemist and physicist; His investigations of the photographic process in the 1850s motivated his work in the new science of spectroscopy. Using its techniques, Crooks discovered (1861) the element thallium, which won him election to the Royal Society. His efforts in determining the weight of thalium in an evacuated chamber led to his research in vacuum physics.

Crooks invented the radiometer in 1875 and, beginning in 1878, investigated electrical discharges through highly evaculated "Crookes tubes." These studies laid the foundation for J. J. Thomson's research in the late 1890's concerning discharge-tube phenomena. At the age of 68, Crookes began investigating the phenomenon of radioactivity, which had been discovered in 1896, and invented a device that detected alpha particles emitted from radioactive material. Crookes maintained an interest in agriculture and warned in 1898 that the world's population would face starvation unless new fertilizer sources were discovered. He was also interested in psychic phenomena. He was knighted in 1897.

The English physicist William Crookes (1832-1919) had devised, by 1875, a still better evacuated tube (a Crookes tube), in which the electric current through a vacuum could more easily be studied. It seemed quite clear that the electric current started at the cathode and traveled to the anode, where it struck the neighboring glass and created the glow of light. Crookes demonstrated this by placing a piece of metal in the tube and showing that it cast a shadow on the glass on the side opposite the cathode. (The electrical experimenters of the eighteenth and nineteenth centuries, beginning with Benjamin Franklin, had assumed that the current flowed from the concentration arbitrarily named positive to that named negative. Crookes had now shown that, in actual fact, the assumption was wrong and that the flow was from negative to positive.)

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CHARLES DARWIN

CHARLES DARWIN
( 1809 - 1882 )

“Survival of the fittest” and “Struggle for existence” whenever we talk about Charles Darwin we remember these words. Charles Darwin was the British naturalist who laid the foundation of the modern theory of evolution.

Darwin was born at Shrewsburg on Feb 12, 1809. Even as a child he developed a passion for collecting insects and minerals. Though he went to Edinburg university to study medicine it was a great failure. So in 1828 he went to Cambridge to dtudy Theology. But there also he neglected studies and spent much of his time in the pursuit of beetles. However he got the degree in 1831. There was a call for a naturalist who could accompany a scientific expedition. It was planned to sail around the world in the ship HMS Beagle. Darwin got it. He made a good lot of collections of bones of extinct animals and also that of the existing. He studied the difference between the two. This helped him to get a clear picture on evolution. He wrote an account of his travels sitting in London after he returned from voyage. In 1859 he explained his theory of evolution in his famous book “The origin of species by natural selecton.” The book became a popular one. He has said in the book that all the varied form of life on earth could in the course of time, have evolved from a common ancestry. At this juncture he said “Fittest Survive.”

The variation of animals and plants under domestication is second book published in 1868. he had his own typical method of collecting information.

Darwin died on April 19, 1882 and was buried near the tomb of Sir Issac Newton. Darwin had ten children. But seven only survived of which four were scientists and three of them were fellows of the Royal Society. The theory of evolution as proposed by Darwin still holds. In his book “The Descent of Man” he has described the evolution of man from apes.

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CHARAKA

CHARAKA

We know nothing about Charaka as a person. But his studies in the field of physiology, etiology and embryology have been made known. His monumental work “Charaka Samhita” an Ayurvedic treatise has gained popularity. It is believed that Charaka was the son of a sage who walked from place to place to cure the sick. Charaka lived 20 centuries ago.

Charaka says the body functions because it contains three dosha or humours namely bile (pitha), phlegm (Kafa) and wind (Vata). According to him, these doshas are produced when dhatus such as blood, flesh and marron act up on the food eaten. When the balance among the three dosha is disturbed there will be illness. To cure illness he prescribed medicinal drugs.

Charaka studied the anatomy of human body and various organs. He found that there are 360 bones in human body including teeth. He regarded heart as a controlling centre and it is connected to the entire body through 13 main channels. If there is any obstruction in these channels the result is disease. He gave a correct picture about the concept of digestion, metabolism and immunity.

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SIR JOHN FREDERICK WILLIAM HERSCHEL



SIR JOHN FREDERICK
WILLIAM HERSCHEL
(1792 - 1871)

He alone could have offered all that was needed for the invention of photography but this multi talented scientist needed it much less than all the others. He had many talents including drawing very well. In 1819 he had already discovered the ability that “hypo” had to fix the photographic images and he is the one who solved the “fixing” problem of pictures that his friend Talbot had. He was the one who first used the terms “photography” “negative” “positive” and “snapshot”. He was the first to photograph glass negatives and in the end he discovered a different photographic method called cyanotype. His contact with other important scientists of his time in Europe and his new ideas in many scientific fields made him without a doubt the leading figure in the English scientific community.

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BRAHMAGUPTA

BRAHMAGUPTA
( B.598)

Brahmagupta was the Scientist to tell first that it is the nature of the earth to attract bodies as it is the nature of water to flow.

Brahmagupta, the eminent Indian mathematician was born at Bhillamala in Gujrat. He was the court astronomer to King Vyagnramukha of the dynastry.

He first framed the ruler of operation for zero. He founded the numerical analysis. He gave a solution to indeterminate equations like ax2 + 1 = y2. He declared that addition or subtraction of zero to or from any quantity, negative or positive, does not affect it. He concluded that the product of any quantity with zero is zero and division of any quantity by zero is infinity.

24+0=24, 24-0=24 or -24-0=-24, 24x0=0
He solved equations like ax+b=0 and ax2+bx+C+0. He is the first mathematician to treat algebra and arithmetic as two separate branches of mathematics.

Brahmasphutasiddhanta and Karanakhandakhadyaka are the two threatises of Brahmagupta. The former contains chapters on arithmetic and algebra. The latter is a hand book on astronomical calculations.

Brahmagupta was an orthodox. He believed that the earth was round. He effectively used algebra for the first time in calculations.

Bhaskara said Brahmagupta is the gem of the circle of mathematicians.

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DMITRI IVANOVICH MENDELEEV

DMITRI IVANOVICH MENDELEEV
( 1834 - 1907 )

Mendeleev was a Russian Chemist who was the first to propose that the seemingly different chemical elements can be sorted out according to certain similarities in their properties. The arrangement he proposed is called the PERIODIC TABLE. His table proved to be a unifying principle in chemistry and led to the discovery of many new chemical elements.

Mendeleev studied chemistry at the university of St.Petersburg. He became a professor of general chemistry in 1867 after he received his Ph.D in 1865. He participated in the early development of oil fields in Southern Russia. He went to USA in 1876 and studied the petroleum industry there. Then he returned to St.Petersburg and resigned his job at university in 1890 in order to support for a group of student activists in their unrest against conservative academic policies.

Mendeleev wore for most of his life a large and baggy jacket without a belt, made of dark grey cloth, that too being his own creation.

In his table Mendeleev found that if elements are arranged in order of increasing atomic weights, elements with similar physical and chemical Properties occur at periodic intervals.

In the periodic table Mendeleev ordered the elements according to their atomic weights. It is an arrangement of the chemical elements in order of increasing atomic number into vertical columns and horizontal rows in such a way that elements with similar properties occupy the same columns. The vertical columns are known as groups and the horizontal rows are known as periods. The groups in the modern periodic table are numbered from 1 to 18 rather I to VIII and 0 in the old classification.

Mendeleevium is a transuranic chemical element belonging to group 3 (a) Old classification III (b) Its atomic number is 101. This element has been named after Mendeleev.

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S. CHANDRASHEKAR

S. CHANDRASHEKAR
(1910)

Subramanyam Chandrashekar was the third Indian to win the Nobel Prize in science. The others earlier were C.V.Raman and Hargovind Khurana.

S.Chandrashekar was born on October 10, 1910 in Lahore. He studied at Madras. He was a book worm and read many books. He did his B.A. at the Presidency college, Chennai. By that time he had many papers to his credit. He went to Cambridge as fellow of Trinity college. He was in USA at the age of 27 becoming an astrophysicist. Otto Struve, Director of Yerkes observatory and an astronomer offered him a job at the Chicago University.

Chandrashekar worked in yerkes observatory also. He had two students Trung Dao Lee and Chen Ning Yang at Chicago.

They wanted Subramanyam as their teacher. In 1997 they were awarded the Nobel Prize in Physics.

Chandrashekar studied the stars. He is best known for “Chandrashekar’s limit”. The fact is that this imposes a limit on the size of a highly dense star known as the white Dwarf. If this type of star has mass in excess of the limit it explodes to become a very bright star called “super nova”. Until all the excess matter is shed into space. Later it was confirmed that all the white dwarf stars in the sky have masses withing this limit. Chandrashekar calculated his limit based on mathematical equations. He also described the formation of “black holes”.

They are super heavy objects. A spoon of which may weigh several thousands of tons. His work on rotating fluid masses and blueness of the sky is highly commendable.

He got the Noble Prize in physics in 1983. He wrote few books and are found valuable.

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JOHANN HEINRICH SCHULZE



JOHANN HEINRICH SCHULZE
(1687 - 1744)


German professor at the University of Altdorf. With experiments, proved that silver nitrate becomes dark due to sunlight and not by temperature. He is the first that created photograms with paper masks, which unfortunately could not last due to lack of paper fixer. His observations that opened the path, for the creation of photography became know after his death

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EDMUND HALLEY

EDMUND HALLEY
( 1656 - 1742 )

Edmund Halley was a British astronomer and a mathematician. He was noted for his work on comets. Comets are formed by the collection of dust and gas. Halley calculated the orbit of a comet he observed in 1682. He proved that the comet was the same one astronomers had seen in 1531 and in 1607. He also predicted that it would return in 1758. This comet has been named after him. It is a bright, periodic comet; its average orbital speed is 76 years. The comet’s size, activity and favourably placed orbit makes it visible to the naked eye at each apparition. It is the only comet to be observed at close range by as many as three space crafts. Giolto Space craft was launched on 2 July, 1985 to study the Halley’s comet. The space craft traveling at a speed of 68 kil metres per second, passed within 500 km of the comet’s nucleus.

Halley was a contemporary of Issac Newton. Infact he was responsible for the publication of Newton’s famous work ‘prinicipia mathematica’. Halley studied the comets with the help of Newton’s Laws of motion. The unfortunate thing is that Halley didn’t live to see the comet. The same comet made its appearance again in 1986. Halley also produced the first accurate map of the stars visible from the Southern HemiSphere. Halley died in the year 1742.

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Sunday, February 8, 2009

PRASANTHA CHANDRA MAHALANOBIS



PRASANTHA CHANDRA
MAHALANOBIS
( 1893 - 1972)

Prasantha Chandra Mahalanobis was born in Calcutta, India on June 29, 1893. As a young boy, Mahalanobis received his education at the Brahmo Boys School in Calcutta. He then went on to the presidency College in Calcutta where he received a Bachelor of Science degree in the field of physics. He then went to England, where he originally intended to study in London, but became so impressed with Cambridge that he decided to join Cambridge University. There he studied mathematics and physics. Because of World War I, his departure was delayed, leading to the meeting that began Mahalanobis' interest in statistics. Mahalanobis was looking around the library at King's College when he was approached by a fellow named Macaulay for his opinion on some volumes of Biometrika, edited by Karl Pearson. Mahalanobis' interest was peaked so much that he bought the entire set of Biometrika that was then published and brought them along with him to India. This was the beginning of a wonderful interest in statistics.
Mahalanobis was the founder of the Indian Statistical Institute (ISI) in 1931, which was actually started in a room of the Baker Laboratory of the physics department at the Presidency College. He also started a new journal in statistics called Sankhya. He established a division within the ISI called the National Sample Survey (NSS). The NSS grew quickly into an agency noted for its use of continuing sample surveys for the collection of socioeconomic and demographic data that covered the whole country. This division, along with Mahalanobis, played such an incredibly vital role in the creation of the second five-year economic plan in India that the government took over NSS and now it functions as a necessary part of the Ministry of Planning.
Mahalanobis' contributions to statistics are quite numerous. His work could always be associated with some field of application. The Mahalanobis distance, called the D statistic, which is used extensively in classification problems, rose out of his work on anthropometric problems. The Mahalanobis distance is used not to find the physical distance from one object to another, but to find the distance in terms of related characteristics and likelihood of occurrence of the two objects. The Mahalanobis in multivariate analysis, along with the interpenetrating network of samples (IPNS) in sample surveys and fractile graphical analysis have now become part of standard statistical methodology.
Mahalanobis received many awards for his work in India and his work on statistics, but some say that his most prized awards would be the Fellowship of the Royal Society and one of the highest civilian awards in India, the Padma Vibhushan. Mahalanobis was always a very active man and he held many positions of importance throughout his life, many of them simultaneously. Yet he never grew tired of his work.
Mahalanobis had many other interests besides statistics and physical science. He enjoyed studying ancient Indian philosophy and he loved to read Bengali literature. Professor Mahalanobis had over 200 published scientific articles along with many non-technical articles in Bengali and English. P.C. Mahalanobis died on June 28, 1972, on the eve of his seventy-ninth birthday.

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JOSEPH NICEPHORE NIEPCE



JOSEPH NICEPHORE NIEPCE
( 1765 - 1833)

French multi-talented inventor. In 1826, (after trying since 1814), invented the “heliogram” and became the first man ever to fix a print. The “heliogram” as a method was extremely time consuming, since it required long time exposures (his first photgraph needed eight hours of exposure time). In 1829 he sighed a contractual agreement with Daquerre in spite of the fact that the latter developed a photographic method of his own after Niepce died in 1833.

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SATYENDRA NATH BOSE



SATYENDRA NATH BOSE

A renowned Indian scientist. He developed a new branch of physics. He worked with Albert Einstein, Madame Curie and other scientists of world renown. He was a veteran teacher revered by his students for his affection, discipline and methodical work.Some students love mathematics. What are the maximum marks they score in it ? It would be a hundred per cent. We would be surprised to be told that some students have secured more than a hundred per cent, wouldn't we! One such student was Satyendranath Bose. As a student of the fourth standard he set up a new record by scoring 110 marks out of 100. This bright youngster later became a scientist and won worldwide fame. Once the great scientist, Niels Bohr, was delivering a lecture. Bose presided.
The fame of Satyendranath Bose as a brilliant student of physics and mathematics has spread the world over. In India, which is still a developing country, he strove hard for the dissemination of science. In addition, he did significant work in the fields of education, politics, music and literature, too. He has come to be popularly known Satyen Bose (S. N. Bose).
Satyendranath Bose was born on the first of January 1894 in Calcutta. Surendranath was his father. He was employed in the Engineering Department of the East India Railway. Satyendranath was the eldest of his seven children; the rest were all daughters. Though Surendranath Bose lost his wife at an early age, without losing heart, he brought up all his children well. It is said that, when Satyen was hardly three years old, a Bengali astrologer made this prediction: "This child will face many obstacles all through his life;
Satyendranath joined Presidency College of Calcutta for higher studies. The period of his stay in Presidency College may be called a Golden Age. The company of good friends and classmates and the guidance of ideal teachers shaped his future life. Some of the most renowned scientists - Meghnad Saha, Nikhilranjan Bose, J. C. Ghosh, J. N. Mukherjee and Girijapathi Bhattacharya - were his classmates. He came to be acquainted with Netaji Subashchandra Bose also. Sharatchandra Bose was his contemporary. These youths were fortunate in their teachers. Eminent scientists like Jagadishchandra Bose, Prafullachandra Ray and S. N. Maitra were their professors. J. C. Bose taught them physics while P. C. Ray taught chemistry. These great scientists were also great patriots. They inspired their students to understand the real values, of life and to set definite goals before themselves.
He joined Dacca University in 1921 as a reader in Physics. While serving in this post he wrote a short article of just six pages in English. It was an article relating to physics, on 'Max Planck's Law' and 'Light Quantum Hypothesis'. This article was sent to Albert Einstein. He had not only won the Nobel Prize but was one of the world's greatest scientists in the twentieth century. The learned professor read the article. This little article brought about a great change in the life of Satyendranath.
Bose first visited Paris in 1924. He stayed there for a year. He conducted research in the Madame Curie Laboratory, which had special facilities. Here he became acquainted with several physicists. The next year, he left Paris for Berlin to join Einstein and work with him. There he came into close contact with noted scientists like Schroedinger and Heisenberg. He participated in all the meetings and discussions held there. While Bose was in Berlin, the post of a professor fell vacant in Dacca University. J. C. Ghosh and other friends persuaded him to apply for the post. Bose had not yet got his doctorate. It was, therefore, difficult for him to secure the professorship. A recommendation from Albert Einstein to select him would have made things easy for him. So, with great hesitation, Bose approached Einstein. Einstein was surprised. He said, "You are so proficient in you’re subject; is their need for any other certificate or recommendation?"
His eightieth birthday was celebrated in 1974. At the Golden Jubilee celebrations of Quanta Statistics, which was held in the same month, he was felicitated. Within a few days after he completed 80, Bose suffered an unexpected and a severe heart attack. He lay ill for some time and breathed his last on the fourth of February 1974. The death of Bose was a great loss not only to India but also to the whole world and especially to the world of science. Bose left behind his wife, two sons five daughters.Einstein and Madame Curie are among the world's great scientists. Bose worked with them. This it self clearly means that India has definitely secured a high place in the world of science.

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SIR HUMPHRY DAVY

SIR HUMPHRY DAVY

( 1778 - 1829)
Chemistry genius, friend and assistant of Wedgwood in his experiments whose results were published at Royal Society, in 1802 by Davy. The problem of “fixing” the images remained in spite of Davy’s breakthroughs in chemistry

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ROGER BACON

ROGER BACON
( 1214 - 1292 )

Roger Bacon is called the father of modern science. His early studies were in the faculty of arts at Oxford and in early 1240 he went to Paris to teach at the Arts faculty of university of Paris. There he turned his attention to science through the influence of Aristotle.

Roger Bacon’s significant contribution to the philosophy of science was his explanation about the role of experience and experiment in conforming or refuting speculative hypothesis. He believed in the practical value of scientific speculation and insisted that the criterion for the use of scientific knowledge should be part of a unifying ethical system. Bacon discovered gun powder, eye glasses and few other equipments.

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PRAFULLA CHANDRA ROY




PRAFULLA CHANDRA ROY


The Bengal renaissance did not leave a single path unfolded. As literature and art reached the peak of realism, science did not lag behind. Along with a host of genius Acharya Jagadish Chandra Bose and Acharya P.C Roy carried forth the quest to reveal the secret of nature. Born on 2nd August,1861 in
Senhati (Khulna) now Bangladesh, he was educated at Hare school, the Albert school, the metropolitan institution and Presidency college. In 1882 he left for England as a Gilchrist scholar and took the degree of Bsc. and Dsc. from Edinburgh University. He got the Hope scholarship in 1887-88. P.C. Roy returned to India in 1888 and joined the Presidency college as a lecturer in Chemistry on 1st July1889. As a professor he was the source of inspiration for the up coming generation. A scientific mind he devoted his spare time in his research in Ayurveda and published 'The History of Hindu Chemistry' in two volumes. Funds crunch, unavailability of necessary equipments and other problems could not cease him and soon he was able to synthesize chemically the compound Potassium Nitrate. He was single-handedly responsible for setting up the first Indian pharmaceutical institution " The Bengal Chemical & Pharmaceutical Works Ltd." in 1901In 1916 he joined the newly established college of science of the Calcutta University and attracted young scholars. He was elected the president of the Indian Science Congress in 1920 where he went on working relentlessly for the cause of the spread of scientific knowledge among the mass. He passed away on June 16th 1944. The emptiness that was created was never to be filled. P.C Roy was a patriot irrationalism and unscientific ideology. He fought against the tyrants of his fields and taught people the true cause behind nature's powers. The rationalist thinker, great scientist and teacher, remarkable entrepreneur and the father of modern Indian Chemical industry helped to build a new Bengal with a bright future

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ANNA ATKINS


ANNA ATKINS
( 1799 - 1871 )
We can consider her the first woman photographer. She studied botanology in a period when access to science and studies for women was almost impossible. In 1841 she came into contact with Talbot who was a friend of her father’s. immediately she became aware of the possibilities that photography could offer to scientific research. She worked with the procedure of cyanotype a technique which was just discovered by Herschel and seemed much easier to her. Because of the stability of cyanotype many of her pictures still exist to this very day. In October 1843 she published the first book containing photographs which was named “British Algae – Cyanotype impressions” which was completed in a period of 10 years and came before Talbot’s publication. “The pencil of nature”.

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BLAISE PASCAL

BLAISE PASCAL
( 1623 - 1662 )
Pascal was a famous mathematician, physicist and a philosopher. “When pressure is applied at any point in a fluid, it gets transmitted equally in all directions”. This is Pascala’s law. Any physics student can state this law. This has helped the inventions of Syringe, hydraulic press and brakes.

Pascal was born on June 19, 1623 in Clermont, France. His father was an accountant in an administrative office. Pascal was good in Mathematics. As 7 years old boy he could make geometrical figures on the ground. At the age of 12 he proved that the sum of the three angles of a triangle is equal to two right angles. At the age of 17 he published an essay relating to mathematics which attracted famous scientist Descartes.

Once Pascal found his father working late in the night doing some calculations with difficulty. To reduce the pressure on his father, Pascal devised a calculating machine in 1642. It was operated by gear wheel. He patented it later.

Pascal invented a triangle which consists of rows of numbers arranged in a specific manner as shown above. It has proved much useful in the study of probability. Pascal did much work on probability, hydrostatics and integral calculus. He was a religious writer having few books to his credit.

He died on August 19, 1662 in Paris.

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ARYABHATA

ARYABHATA

Aryabhata was an astronomer. He was born in Kerala. He studied at the University of Nalanda. He was honoured by the then Gupta ruler Buddhgupta and appointed the head of University.

Aryabhata gave the value of O (Pi) as 3.1416. He was the first to deduce that the earth is round and it rotates on its own axis creating day and nights. He also declared that moon is dark and shines only because sunlight. He believed that the earth is the centre of the universe.

Aryabata devised a method to express big numbers like 100,000,000 in words. He actually found a solution to the intermediate equations like ax-by=c.

Aryabhata’s legendary epic “Aryabahatiya” deals with the various aspects of mathematics and astronomical calculations. He wrote one more treatise “Aryabhata Siddhanta” which was a guide to determine auspicious times for various rituals. Indian’s first Satellite was name Aryabhata.

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