Showing posts with label Chemistry. Show all posts
Showing posts with label Chemistry. Show all posts

Sunday, June 13, 2010

10-10 Series (Karl Landsteiner)

Karl Landsteiner, winner of the Nobel Prize in...
1. When did Karl Landsteiner win Nobel Prize for Medicine?
a) 1930

2. When was Karl Landsteiner born?
b) 14 June 1868

3. Where was Karl Landsteiner born?
d) Vienna

4. Which university did Karl Landsteiner attend?
c) Vienna

5. When did Karl Landsteiner publish his discovery of human ABO blood group system?
a) 1901

6. For what did Karl Landsteiner win Nobel Prize for Medicine?
b) Discovery of human blood groups

7. Who co-discovered Rhesus System with Karl Landsteiner?
c) Alexander Wiener

8. When did Karl Landsteiner publish The Specificity of Serological Reactions?
d) 1936

9. When did Karl Landsteiner die?
b) 26 June 1943

10. Where did Karl Landsteiner die?
d) New York

Enhanced by Zemanta

Monday, June 7, 2010

Types of bonds: Covalent bonds

It is often the forces, or bonds, between the atoms which provide the initial clues about why certain substances have specific properties 


The nature of the bond dictates many of the physical properties of a substance - viz. the remarkable differences between diamond and graphite, though they are both forms
of Carbon.

What holds electrically neutral atoms together into molecules and even larger groups - as liquids and solids ?
Bonding between atoms to form large aggregates is possible when the energy of the combined system is less than that of the system of separate noninteracting atoms.

Stability of bonding is determined by
(i) Coulomb attraction between opposite charges (Potential Energy contribution) and
(ii) lowering of Kinetic Energy by delocalization of the wavefunction of the electrons participating in the bonding.

We will look at four types of bonds: covalent, ionic, metallic and Van der Waals [Hydrogen bond is essentially an especially strong type of Van der Waals bond].

Bonds between atoms are of the followng types:
Ionic bonds
Covalent bonds
Metallic bonds

What are the possibilities when two atoms are brought close to each other ?:
1. A covalent bond is formed - through sharing of one or more pairs of electrons by the two atoms - the KE of participating electrons is lowered (by Uncertainty Principle)
2. An ionic bond is formed - an extreme case of covalent bond, when one or more electrons from one atom is transferred to the other
3. No bond is formed - when the electronic structure of two atoms overlap they form a single system and are subject to Pauli exclusion principle - may result in electrons being pushed to higher energy states making the bond unstable. .

Mechanism of the Covalent Bond
How is it possible for two nuclei to share an electron -- quantum tunneling of the electron wavefunction with high frequency
Why electron sharing leads to lower total energy and a stable system -- if the electron occupies a larger volume, the uncertainty principle implies lower momentum and hence lower KE.
.
Examples:
  • H2+ molecular ion (2 protons, 1 electron): spatially symmetric wavefunction most stable giving a bond energy of 2.65 eV.
  • H2 molecular ion (2 protons, 2 electrons): spatially symmetric, spin antiparallel wavefunction most stable.
  • Complex molecules: the stability of the bonding is determined by the outermost (valence) electrons only. Alterations in the valence electron wavefunctions due to interaction with other atoms determine the geometry of the bond and gives rise to the directed nature of covalent molecular bonds. Example: tetrahedral structure of diamond, methane (CH4).
Why He2 or H3 cannot exist ? Why is water (H2O) molecule stable ? : Pauli exclusion principle
Bottomline:
All covalent crystals are hard (diamond is the hardest substance known), have high melting point, are insulators and are insoluble in all ordinary liquids. Cohesive energies of 6-12 eV/atom are typical for covalent bonds.

Looking further ?
Fullerenes (e.g., C60, pictured on the left ) are formed by sp2 type of covalent bonds between neighboring Carbon atoms.

What is ligand?

http://www.bioinformaticscourses.com/ISB/sp2003/4HVP/ligandA
In chemistry, a ligand is an atom, ion or functional group that is bonded to one or more central atoms or ions, usually metals generally through co-ordinate covalent bond. An array of such ligands around a centre is termed a complex.


The central atom usually has a positive charge which is stabilised by donation of negative charge from the ligands.

Neutral or negatively charged centres are also known, usually stabilised by donating electron density back to the ligand in a process known as "back-bonding". 

The charge on the central atom constrains the number of ligands that may be bonded, since each type of ligand donates a characteristic number of electrons and there is a requirement for overall neutrality. If the directly-bonded ligands (the "inner-sphere" ligands) do not balance the charge, this may be done by purely ionic interaction with another set of ions (the "outer-sphere" ligands).

The inner-sphere ligands arrange themselves in a certain geometry, fixed for a given complex but in some cases mutable by reaction to another stable isomer. Ligands which bind to the central atom through more than one site of their own are termed polydentate; a ligand binding through two sites, for example, is bidentate.
Reblog this post [with Zemanta]

Thursday, June 3, 2010

Preservatives

Various preserved foodsImage via Wikipedia
All food products except for the one growing in your kitchen garden has food preservatives in them. Every manufacturer adds food preservative to the food during processing. The purpose is generally to avoid spoilage during the transportation time.

Food is so important for the survival, so food preservation is one of the oldest technologies used by human beings to avoid its spoilage. Different ways and means have been found and improved for the purpose. Boiling, freezing & refrigeration, pasteurizing, dehydrating, pickling are the traditional few. Sugar and salt are also often used as preservatives food. Nuclear radiation is also being used now as food preservatives. Modified packaging techniques like vacuum packing and hypobaric packing also work as food preservatives.

Food Preservation is basically done for three reasons
  • To preserve the natural characteristics of food
  • To preserve the appearance of food
  • To increase the shelf value of food for storage.

Natural Food Preservatives

In the category of natural food preservatives comes the salt, sugar, alcohol, vinegar etc. These are the traditional preservatives in food that are also used at home while making pickles, jams and juices etc. Also the freezing, boiling, smoking, salting are considered to be the natural ways of preserving food. Coffee powder and soup are dehydrated and freeze-dried for preservation. In this section the citrus food preservatives like citrus acid and ascorbic acid work on enzymes and disrupt their metabolism leading to the preservation.

Sugar and salt are the earliest natural food preservatives that very efficiently drops the growth of bacteria in food. To preserve meat and fish, salt is still used as a natural food preservative.

Chemical Food Preservatives

Chemical food preservatives are also being used for quite some time now. They seem to be the best and the most effective for a longer shelf life and are generally fool proof for the preservation purpose. Examples of chemical food preservatives are:

  • Benzoates (such as sodium benzoate, benzoic acid)
  • Nitrites (such as sodium nitrite)
  • Sulphites (such as sulphur dioxide)
  • Sorbates (such as sodium sorbate, potassium sorbate


Antioxidants are also the chemical food preservatives that act as free radical scavengers. In this category of preservatives in food comes the vitamin C, BHA (butylated hydroxyanisole), bacterial growth inhibitors like sodium nitrite, sulfur dioxide and benzoic acid.

Then there is ethanol that is a one of the chemical preservatives in food, wine and food stored in brandy.
Unlike natural food preservatives some of the chemical food preservatives are harmful. Sulfur dioxide and nitrites are the examples. Sulfur dioxide causes irritation in bronchial tubes and nitrites are carcinogenic.

Artificial Preservatives

Artificial preservatives are the chemical substances that stops of delayed the growth of bacteria, spoilage and its discoloration. These artificial preservatives can be added to the food or sprayed on the food.

Types of Artificial Preservatives Food

  • Antimicrobial agents
  • Antioxidants
  • Chelating agent

In antimicrobial comes the Benzoates, Sodium benzoate, Sorbates and Nitrites.
Antioxidants include the Sulfites, Vitamin E, Vitamin C and Butylated hydroxytoluene (BHT)
Chelating agent has the Disodium ethylenediaminetetraacetic acid (EDTA), Polyphosphates and Citric acid

Harmful Food Preservatives

Although preservatives food additives are used to keep the food fresh and to stop the bacterial growth. But still there are certain preservatives in food that are harmful if taken in more than the prescribed limits.

Certain harmful food preservatives are

Benzoates

This group of chemical food preservative has been banned in Russia because of its role in triggering allergies, asthma and skin rashes. It is also considered to cause the brain damage. This food preservative is used in fruit juices, tea, coffee etc.

Butylates

This chemical food preservative is expected to cause high blood pressure and cholestrol level. This can affect the kidney and live function. It is found in butter, vegetable oils and margarine.

BHA (butylated hydroxyanisole)

BHA is expected to cause the live diseases and cancer
. This food preservative is used to preserve the fresh pork and pork sausages, potato chips, instant teas, cake mixes and many more.

Caramel

Caramel is the coloring agent that causes the vitamin B6 deficiencies, genetic effects and cancer. It is found in candies, bread, brown colored food and frozen pizza.

In addition to this there are many other harmful food preservatives. These are Bromates, Caffeine, Carrageenan, Chlorines, Coal Tar AZO Dies, Gallates, Glutamates, Mono- and Di-glycerides, Nitrates/Nitrites, Saccharin, Sodium Erythrobate, Sulphites and Tannin

Preservatives Food Additives

All of these chemicals act as either antimicrobials or antioxidants or both. They either inhibit the activity of or kill the bacteria, molds, insects and other microorganisms. Antimicrobials, prevent the growth of molds, yeasts and bacteria and antioxidants keep foods from becoming rancid or developing black spots. They suppress the reaction when foods comes in contact with oxygen, heat, and some metals. They also prevent the loss of some essential amino acids some vitamins
.

Some common preservatives and their primary activity
Chemical Affected
Organism(s)
Action

Use in Foods
Sulfites
Insects & Microorganisms
Antioxidant

Dried Fruits, Wine, Juice
Sodium Nitrite
Clostridia
Antimicrobial

Cured Meats
Propionic Acid
Molds
Antimicrobial

Bread, Cakes, Cheeses
Sorbic Acid
Molds
Antimicrobial

Cheeses, Cakes, Salad Dressing
Benzoic Acid
Yeasts & Molds
Antimicrobial

Soft Drinks, Ketchup, Salad Dressings

There are other antioxidants like Sodium Erythorbate, Erythorbic Acid, Sodium Diacetate, Sodium Succinate, Grape Seed Extract, Pine Bark Extract, Apple Extract Tea Proplyphenols, Succinic Acid and Ascorbic Acid and food preservatives like Parabens and Sodium Dehydro Acetate used frequently for preservation.
Reblog this post [with Zemanta]

Thursday, October 29, 2009

Triple point

Triple point

From Wikipedia, the free encyclopedia

In thermodynamics, the triple point of a substance is the temperature and pressure at which three phases (for example, gas, liquid, and solid) of that substance coexist in thermodynamic equilibrium.[1] For example, the triple point of mercury occurs at a temperature of −38.8344 °C and a pressure of 0.2 mPa.

In addition to the triple point between solid, liquid, and gas, there can be triple points involving more than one solid phase, for substances with multiple polymorphs. Helium-4 is a special case that presents a triple point involving two different fluid phases (see lambda point). In general, for a system with p possible phases, there are {p\choose 3} = \frac{p(p-1)(p-2)}{6} triple points.

Saturday, October 3, 2009

Terminolgy watch

Confusing Terminology in Platial
1. The study of human populations, including their size, growth, density and distribution as well as statistics regarding birth, marriage, disease and death
Demography

2. The study of the formation and structure of the features of the surface of the Earth or another planetâۉ„¢s surface
Geomorphology

3. The study of the properties, distribution, use and circulation of the earthâۉ„¢s water and the atmosphere in all of its forms
Geology

4. Scientific study of oceans
Oceanography

5. The study of life in prehistoric times by using fossils
Paleontology

6. The study of rocks with respect to their occurrence, structure, origin, history, and mineral content
Petrology

7. Science deals with the production and study of Maps and charts
Cartography

8. The study and description or mapping of the entire world or the universe is called
Cosmography

9. The study of biological function and mechanics, and the application of them to machine design is called
Bionics

10. A branch of zoology dealing with the study of sea shells and the animals that inhabit them is called
Conchology

11. The scientific study of climates
Climatology

12. The study of, or the science of determining, the order in which things occur
Chronology

13. The study of recurring cycles of events in the natural world
Chronobiology

14. The application of statistical techniques to biological studies
Biometry

15. The scientific study of the chemical substances, processes, and reactions that occur in living
Biochemistry

16. The study of Crimes, Criminals and the punishment of criminals is called
Criminology

17. The preparation of maps in which specific areas or regions are delineated and often highlighted
Chorography

18. The scientific study of Bacteria is called
Bacteriology

19. Study of projectiles is called
Ballistics

20. The study of the physical properties, origin, and development of celestial objects and events is called
Astrophysics

21. The scientific study of ancient cultures through the examination of their material remains
Archaeology

22. The cultivation of trees and shrubs for study, ornamentation, or profit
Arboriculture

23. The branch of science that studies the physical structure of animals, plants, and other organisms
Anatomy

24. The branch of botany concerned with the scientific study of algae
Algology or Phycology

25. The scientific study of the universe, especially of the motions, positions, sizes, composition, and behavior of celestial objects is called
Astronomy

26. The branch of statistics that deals with gas in equilibrium and with gases and bodies in them is called
Aerostatics

27. The branch of meteorology concerned with the study of clouds
Nephology

28. The study of the positions of the Moon, Sun, and other planets in the belief that their motions affect human beings
Astrology

29. The branch of medicine concerned with the study and treatment of diseases of the kidneys
Nephrology

30. The scientific study of Earthâۉ„¢s atmosphere especially its patterns of climate and weather
Meteorology

31. The scientific study of units of measurements
Metrology

32. The relationship between organism and its environment is called
Ecology

33. The science that deals with all forms of life, including their classification, physiology, chemistry, and interactions
Biology

34. The branch of geology that examines the formation and structure of the features of the surface of the Earth or another planetâۉ„¢s surface
Geomorphology

35. .....is the science of the intricate series of relationship between living organisms and their living and non living surroundings
Ecology



37.Bibliography given in a research report helps :
those interested in further research and studying the problem from another angle

38. The scientific study of lakes and other bodies of fresh water, including their physical and biological features
Limnology

39. The study of the bumps on the outside of the skull, based on the now discredited theory that these bumps reflect somebodyâۉ„¢s character
Phrenology

40. The science or study of drugs is
Pharmacology

41. Cultivation of flowers
Floriculture

42. The keeping of bees, especially for commercial purposes
Apiculture

43. The science or practice of growing grapevines, especially for wine making
Viticulture

44. The controlled breeding, hatching, and rearing of fish, especially for scientific or commercial purposes
Pisciculture


46.  The branch of anatomy concerned with the study of the structure and functions of bones
Osteology

47. The scientific study of sleep or hypnosis
Hypnology

48. The study of characteristics of rocks is
Lithology

49. The study of fish
Ichthyology

50. The science in which chemicals are used for the treatment of diseases is known as
Chemotherapy

Thursday, September 24, 2009

Scientist Watch

Avul Pakir Jainulabdeen Abdul Kalam, current p...Image via Wikipedia

PROMINENT SCIENTISTS

Abdul Kalam, Dr A.P.J.: is credited with advancement of missile technology in India. He was honoured with Bharat Ratna award on November 26, 1997. He is known as “father of India’s Missile Technology”. Elected 11th President of India.

Alvares, Luis W.: is an American physicist teaching at the University of California, Berkeley, U.S.A. He won the Nobel Prize for Physics in 1968 for an important breakthrough he made in elementary physics in 1960 when he discovered a new resonance particle—a discovery that shattered the then prevailing notions as to how matter was built.

Anfinsen, Dr Christian B.: of the U.S.A.’s National Institute of Health, Bethseda, Maryland was one of the three co-winners of the Nobel Prize in Chemistry, 1972.

Archimedes: Greek mathematician (born in Sicily) who lived about 250 B.C. is known for the discovery of the Archimedes’ principle viz., The volume of any insoluble solid can be found by noting its loss of weight when immersed in water. He is also credited with the invention of Archimedean Screw, a cylindrical device for raising water.

Arrow, Kenneth, J.: of Harvard University, U.S.A. is co-winner of the Nobel Prize for Economics, 1972 with Sir John Richard Hicks of Oxford University. The two men are known for their pioneering contributions to general economic equilibrium and welfare theories.

Aryabhatta: (A.D. 476-520) after whom India’s first scientific satellite has been named, was a great Indian astronomer and mathematician. Among his important contributions are the recognition of the importance of the mov ement of the earth round the sun, determination of the physical parameters of various celestial bodies, such as diameter of the earth and the moon. He laid the foundations of algebra and was responsible for pointing out importance of “zero”.

Avogadro, Amedeo: (1776-1856) Italian physicist; founder of Avogadro’s hypothesis: “Equal volumes of all gases under similar conditions of temperature and pressure, contain equal  number of molecules.” He also defined a molecule.

Bardeen, Prof John: of the University of Illinois (U.S.A.) is co-winner of the Nobel Prize for Physics, 1972 (with Prof Leon N. Cooper and Prof John Robert Schrieffer) for researches into the “theory of super-conductivity” usually called the BCS theory.

Barnard, Christian: South African surgeon who shot into world news in December 1967 when he completed the first heart transplant operation on Louis Washkansky.

Beadle, Dr G.: American scientist awarded Nobel Prize for medicine in 1958 for his work concerning the actual basis of heredity—the way in which characteristics are transmitted from one generation to another.

Becquerel, Henri: (1852-1908) French physicist known for his discovery in 1896 of Becquerel rays, the first indications of radio-activity; these rays were later named gamma rays. He shared Nobel Prize for Physics with the Curies in 1903.

Berzelius, J.J: (1779-1848) Swedish Chemist, known for introduction of chemical shorthand symbols and atomic weights.

Bessemer, Sir Henry: (1813-1898) English engineer. He invented the process for the manufacture of steel known after his name.

Bhabha, Dr H.J.: (1909-66) Indian scientist. He published important papers on Cosmic Rays and Quantum Theory. He was professor at the Indian Science Institute, Bangalore; Chairman, Atomic Energy Commission; Director, Tata Institute of Fundamental Research; President, Indian Science Congress in 1951 and presided at the Atoms for Peace Conference held at Geneva in 1956. He had many significant researches in structure of atom and contributed largely to the setting up of atomic reactors at Trombay (Mumbai).

Bhagvantam, Dr S.: is an eminent Indian scientist who has made a rich contribution to research in radio astronomy and cosmic rays. He has published more than 150 research papers and several books. He retired in October 1969 as the Scientific Adviser to the Ministry of Defence, and Director General of the Defence Research Development Organisation. He is an old-time associate of Sir C.V. Raman.

Bhaskaracharya: Born in A.D. 1114, he was almost the last great Hindu mathematician and astronomer until modern times. He wrote Sidhanta-Siromani in 1150  which consisted of two mathematical and two astronomical parts. Bhaskara anticipated the modern theory on the convention of signs (minus by minus makes plus, minus by plus makes minus). He also anticipated Kepler’s method for determining the surface and volume of sphere.

Bhatnagar, Dr Shanti Swarup: (1895-1955) great Indian scientist. He was Director of Council of Scientific and Industrial Research (C.S.I.R.). A chain of National Laboratories has been established in the country due to his able organisation and unbounded energy.

Bohr, Neils: (born 1885) Danish Physicist. He was awarded Nobel Prize for Physics in 1922. He greatly extended the theory of atomic structure of devising an atomic model in 1913 and evolving theory of nuclear structure; assisted America in atom bomb research.

Borlaug, Norman Ernest: American agricultural scientist and winner of the Nobel Prize for Peace in 1970. He was one of those who laid the groundwork of the Green Revolution.

Bose, Sir J.C.: (1858-1937) Eminent Indian physicist and Botanist; founder of Bose Research Institute, Calcutta. Inventor of crescograph which is used to magnify movements made by plants.
Bose, S.N.: Eminent Indian scientist who won fame by expounding the Bose-Einstein theory, which is concerned in detection of a group of nuclear particles—named after him ‘Boson’ in recognition of his contribution to the subject; contributed to Plank’s law. Professor of physics, Calcutta University; nominated member to the Council of States. Awarded Padma Vibhushan in 1954. He died on February 4, 1974.

Boyle, Robert: (1627-1691) Irish natural philosopher; one of the founders of modern chemistry and Boyle’s law: “Temperature remaining constant, volume of a given mass of gas varies inversely as its pressure.”

Bragg, Sir William: (1862-1942) British physicist known for researches on the behaviour of crystals with regard to X-rays incident upon them. Author of the book: “Atomic Structure of Minerals”.

Cavendish, Henry: (1731-1810) English physicist and chemist; he discovered properties of hydrogen in 1766 and identified it as an element.

Chadwick, Sir James: (1891-1974) British physicist. He discovered the particle in an atomic nucleus which became known as the neutron, because it has no electric charge.

Chandrasekhar, Dr Subramanian: He was a scientist of Indian origin settled in the U.S.A., who shared the 1983  Nobel Prize for physics with an American, William Fowler. He was one of the most outstanding astrophysicist of the world.
His theory of stellar evolution—the birth and death of stars—is more than 30 years old. When he first propounded his finding that old stars just collapse and disappear in the light of denser stars of low light, the world’s top-flight astronomers laughed at him and rejected his theory. A disappointed Dr Chandrasekhar left Trinity, Cambridge, to pursue his research in the University of Chicago. Over the next two decades the “Chandrasekhar Limit” became an intrinsic part of text-books on advanced astrophysics. Global recognition and awards poured in, and the 1983 Nobel Prize tops a remarkable career spanning almost half a century.

Charak: (c.A.D. 80-180) was a court physician to Kushan king Kanishka. His writings are invaluable in the study of Hindu medicine.

Charles, Jacques Alexander Cesar: (1746-1823) a French scientist of great repute. He was the first to make a balloon ascension with hydrogen. He is known for his work on the effect of temperature on the volume of gases.

Clarke, Arthur C.: He is known for his suggestion of the concept of Geostationary Orbit.

Clark Maxwell, James: (1831-79) British physicist. His theoretical work prepared the way for wireless telegraphy and telephony. His principal works include: Perception of Colour, Colour Blindness, Theory of Heat, Electricity and Magnetism, Matter and Motion.

Claude, Albert: is a biologist of Luxembourg who shared the 1974 Nobel Prize in Medicine. His field of research relates to causes and treatment of cancer.

Columbus, Christopher: (1446-1506) A well-known Italian navigator set out on his first voyage in 1492; he discovered West Indies Islands, Cuba and Bahamas; he also discovered South America in 1498.

Cooper, Leon N.: Of the Brown University, Providence, Rhode Island (U.S.A.) was one of the three co-winners of the Nobel Prize in Physics, 1972 for researches into the theory of super-conductivity.

Copernicus: (1413-1543) A prominent astronomer of Poland who discovered the “Solar System”.

Cornforth, John Warcup: co-winner of the 1975 Nobel Prize in Chemistry is a deaf professor. He is an Australian living in England. His chief distinction is mapping out the formation of cholesterols which he calls “a great discovery” and contains the key to, for instance, sex hormones.

Curie, Madame Marie: (1867-1934) Polish physicist and chemist; famous for her discovery of radium was awarded Nobel Prize in chemistry in 1911 and shared Nobel Prize in physics in 1903 with her husband and Becquerel.

Dalton, John: (1766-1844) British scientist. He was founder of the Atomic Theory and law of Multiple Proportions.

Darwin, Charles: (1809-82) was the British scientist who discovered the principle of natural selection. His famous work is “The Origin of Species”.

Davy, Sir Humphrey: (1771-1829) British chemist. First to apply electric current for the isolation of metals. Studied anaesthetic action of nitrous oxide, properties of chlorine and alkali metals.

Debreu, Gerard: Gerard Debreu of the University of California at Berkeley, who has been awarded the 1983 Nobel memorial prize in economics is known for his research on market equilibrium in which he “incorporated new analytical methods into economic theory”.
Mr Debreu has expanded on a mathematical model designed by the two men in the early 1950s that confirmed the logic of Adam Smith’s “theory of general equilibrium” in which prices supply and demand tend to reach a balance within a free market economy.

Delbrueck, Dr Max: is a German-born American doctor working at the California Institute of Technology. He was one of the three American co-winners of the Nobel Prize for Medicine, 1969 for discoveries in molecular genetics.

De Vries: is known for Mutation theory.

Dhanvantri: a great physician during the reign of Chandragupta Vikramaditya (375-413 A.D.).

Dhawan, Prof Satish: He is former Chairman of the Indian Space Research Organisation (ISRO). Under his dynamic leadership India entered Space Age by launching “Aryabhata”, a scientific satellite, into space on April 19, 1975.

Edelman, Dr Gerald Maurice: of U.S.A. is co-winner of the Nobel Prize for Medicine, 1972. He is known for researches into the chemical structure of blood-proteins or antibodies which shield the human body against infection. He shared the prize with Dr Rodney Robert Porter of Oxford. The two Nobel-laureates were able to break the  giant molecules formed by antibodies into their component sections.

Edison, Thomas Alva: (1847-1931) American inventor of Dutch-Scottish parentage. He started life as a newsboy and then a telegraph operator. His inventions include: phonograph, the incandescent lamp, a new type of storage battery, an early form of cinematography etc.

Einstein, Prof Albert: (1879-1955) was German-Swiss world-famous scientist known for his theory of relativity. He was awarded Nobel Prize for his work on photoelectric effect.

Faraday, Michael: (1791-1867) An eminent English scientist; showed great prominence in the field of electromagnetism; discovered the laws of electrolysis and wrote a number of useful books on the subject.

Fleming, Alexander: (1881-1955) British bacteriologist. His notable discovery was lysozyme (1922), followed by penicillin (1929)—an antibiotic drug.

Fleming, Sir John Ambrose: (1849-1945) British physicist and engineer who was pioneer in the development of the telephone, electric light and radio.

Fraunhofer: German physicist. He gained prominence on the researches of ‘Light’ while performing spectrum-analysis of Sunlight; he discovered the spectrum to be crossed with some indifferent black lines. And the lines are so named as Fraunhofer Lines.

Freud, Sigmund: (1856-1939) originator of psycho-analysis, born of Jewish parents. Works: The Interpretation of Dreams; The Psychopathology of Every-day Life; The Ego and the Id; Civilization and Its Discontents.

Gabor, Dr Dennis: Who won the 1971 Nobel Prize award for Physics is a 71-year old British electrical engineer working as a scientist in the U.S.A. He was cited for his “invention in development of the holographic method”—three dimensional photography. Dr Gabor was the 16th Briton to have won the Nobel Prize in Physics. He was born and educated in Hungary. He later worked as research engineer in Germany and came to join the staff of the Imperial College in London in 1949. He invented holography in the late forties. But the science became fully developed with the coming of the laser in 1960. A holographic image is so lifelike that a viewer can see around things in a holograph by moving his head just as he looks around the real object.

Galileo: (1564-1642) Italian scientist. He was professor of mathematics. His view that all falling bodies, great or small, descend with equal velocity, made him unpopular with the orthodox scientists. He improved telescope and with it was the first man to see the satellites of Jupiter.

Gell-Mann, Prof Murray: was the recipient of the 1969 Nobel Prize for Physics. He is a teacher in the California Institute of Technology. Born in New York in 1929, Prof Gell-Mann has been the leading theorist in elementary particle research for the last 15 years. He was the 28th American to be awarded the Nobel Prize for Physics in which the U.S.A. now leads. The Nobel Prize was given to him for “his classification of elementary particles and their interactions”.

Goddard, Robert H.: was an American who mentioned the possibility of shooting a rocket to the moon in a paper entitled “A Method of Reaching Extreme Altitudes” published by him in 1919. By 1926 he had put some of his ideas into practice. He is looked upon as one of the pioneers of space research.

Graham, Thomas: (1805-1914) Scottish chemist called the “father of colloidal chemistry”. He did remarkable work on diffusion of substances in solution.

Heisenberg: is known for his theory of Uncertainty Principle.

Hahn, Otto: was a German pioneer of nuclear research. He won the Nobel Prize for Chemistry in 1944. It was Hahn who had proved in 1938 that atomic fission can be achieved by bombarding uranium with neutrons. The discovery revolutionised atomic science.

Hall, Charles Martin: (1863-1914) American chemist who discovered the modern method of extraction of aluminium by electrolysis of bauxite in 1886.

Harvey, William: (1578-1675) English physician who discovered the circulation of blood.

Herzberg, Dr Gehard: has been awarded the 1971 Nobel Prize in Chemistry, for his researches in atomic and molecular structures, particularly free radicals. He is the first Canadian to win a Nobel Prize in Chemistry.

Holley, Robert: Co-winner of the Nobel Prize for Medicine, 1968, belongs to Cornell. His researches into the genetic code and its function in building protein led to the discovery of the complete structure of a transfer RNA molecule and the way it works.

Hopkins, Sir Frederick Gowland: He was an eminent English biochemist famous for his important work on proteins and vitamins. He was awarded the Nobel Prize in medicine in 1929 for the discovery of Vitamin D.

Hoyle, Fred: is a British scientist and science-fiction writer who won the £ 1,000 Kalinga Prize in 1968.

Jenner, Edward: (1749-1823) Eminent English physician who discovered the vaccination system of alleviating small pox.

Josephson, Dr Brian: is a British scientist who co-shared the 1973 Nobel Prize for physics for “his theoretical predictions of the properties of a super-current through a tunnel barrier, in particular those phenomena which are generally known as Josephson effects”.

Joshi, Prof S.S.: He has done commendable work on physical and chemical reactions under electric discharge on active nitrogen; colloids; hydrogen peroxide; permanganates and  a phenomenon called “Joshi Effect”.

Joule, James Prescott: (1874-1937) a great English physicist who first demonstrated that mechanical energy can be converted into heat.

Kepler, Johannes: (1571-1630) German astronomer. He discovered 3 laws of planetary motion that bear his name viz., (1) The orbit of each planet is an ellipse with the sun at one of the foci; (2) the Radius vector of each planet describes equal areas in equal times; (3) The squares of the periods of the planets are proportional to the cubes of their mean distances from the sun.
Kepler had evolved a set of laws governing man in space with rare prescience. In a kind of allegory, he referred to the dangers of solar radiation, the need to overcome gravitational resistance, gravitational capture of spacecraft by the moon etc. What he wrote nearly 360 years ago was, however, little understood and his family was persecuted for it. His mother had to die in jail having been condemned as a witch.

Khorana Hargobind: who shared with two others the 1968 Nobel Prize for Medicine is an Indian by birth and an American by domicile. He deciphered the genetic code and later created an artificial gene.

Krishnan, Dr K.S.: (born 1898) collaborated with Sir C.V. Raman in the discovery of “Raman Effect”. President, Indian Science Congress, 1949; delegate to several international scientific conferences; Director, National Physical Laboratory, New Delhi.

Lavoisier, A.L.: (1743-1794) French chemist; established law of Indestructibility of Matter, Composition of Water and Air.

Lister, Joseph: (1827-1912) British surgeon. He was the first to use antiseptic treatment for wounds; introduced antiseptic surgery.

Lodge, Sir Oliver Joseph: (1851-1940) British physicist. He is chiefly known for his researches on radiation, and the relation between matter and ether.

Lovell, Sir Bernard: He is professor of Radio-Astronomy in the University of Manchester and is also Director of the Jodrell Bank Observatory. He remains very much in the news for tracking space-ships.

Lysenko: Author of Agro-biology, Lysenko gained fame as a Soviet geneticist. In 1948, he declared the Mendelian theory obsolete and erroneous.

Marconi: (1873-1937) Italian scientist; pioneer in wireless telegraphy and radio.

Max Planck: He was a German theoretical physicist who formulated the quantum theory which revolutionized physics. He was awarded the Nobel Prize in 1918.

Mendel, Johann Gregory: (1822-84) Austrian monk and naturalist whose discovery of certain principles of inheritance (heredity) is of deep significance in the study of biology.

Mendeleef, D.I.: (1834-1901) a Russian chemist, founder of periodic law and famous for the development of petroleum and other industries in Russia.

Meyer, Victor: (1848-1897) discovered a method to determine the molecular weights of volatile substances.

Morley, Edward William: (1818-1923) American chemist and physicist best known for his work in determining the composition of water by weight.

Moseley, Henry G.: (1887-1915) British physicist who did valuable work on atomic structure, and in 1913, devised the series of atomic numbers.

Nagarjuna: the renowned chemist of Buddhist era whose works are mostly preserved in  China and Tibet. A great Philosopher and Chemist. He makes a mention of crucibles, distillation stills, sublimation, colouring process, alloying of metals, extraction of copper and use of many metallic oxides in medicines. About chemistry he said, “As long as the science of chemistry prevails, let hunger, pain and poverty not torment men.”

Nag-Chowdhury, B.D.: an eminent Indian nuclear physicist, known all over the world.

Narlikar, J.V.: Indian scientist; co-author of Hoyle-Narlikar Theory of continuous creation. The theory of which he is co-author has been hailed as supplying some important missing links in Einstein’s theory of Relativity. The new theory of gravitation propounded by both the scientists, Narlikar and Hoyle, shows that gravitation is always attractive and there is no gravitational repulsions.

Newton, Sir Isaac: (1642-1727) was the British natural philosopher. He discovered binomial theorem; the differential and integral calculus. He expounded the universal law of gravitation. He is author of Principia Mathematica.

Nirenberg, Dr Marshall: is a U.S. molecular biologist who shared the 1968 Nobel Prize for Medicine with Dr Robert Holley and Dr Hargobind Khorana. Nirenberg is the author of a very simple but ingenious experiment which helped a great deal in clarifying the general character of the genetic code.

Oberth, Hermann: is a Rumanian-German Professor who is credited with establishing the experimental basis of modern rocketry. In 1923, the publication of his book, “The Rocket into Interplanetary Space” aroused great interest in space travel.

Ohm, George Simon: (1787-1854) physicist and mathematician; discovered the law known as Ohm’s Law.

Onsager, Lars: is a U.S. Professor who became a Nobel laureate in 1968 by winning the prize for Chemistry “for the discovery of the reciprocal relations bearing his name which are fundamental for the thermo-dynamics of irreversible processes”.

Paraceisus: (1493-1541) a Swiss mystic and chemist. He was the first to employ laudanum and antimony in Pharmacy.

Parson, Sir Charles: (1854-1931) British  engineer;  inventor of Parson steam turbine.

Pasteur, Louis: (1822-95) He was a French chemist who discovered the causes of fermentation in alcohol and milk and founded the Pasteur Institute in 1888. He made researches in silkworm disease, anthrax, and hydrophobia.

Pauling, Linus: American bio-chemist. He applied the quantum theory to chemistry and was awarded Nobel Prize (1954) for his contribution to the electrochemical theory of valency.

Porter, Dr Rodney Robert: is Professor of Biochemistry in Oxford University. Dr Porter is known for his discoveries relating to the chemical structure of antibodies.

Priestley, Joseph: (1733-1804) British Chemist; discovered oxygen and methods of collecting gases.

Pythagoras: is known as the father of Geometry.

Rainwater, James: of the U.S.A. who co-shared the 1975 Nobel Prize in Physics is known for the development of the theory that atomic nucleus is not always spherical but can also be egg-shaped which has no immediate practical meaning but is extremely essential to scientists.

Ramanna, Dr Raja: former Director of Bhabha Atomic Research Centre at Trombay. He was one of the Indian scientists associated with staging India’s first nuclear blast at Pokhran on May 18, 1974.

Raman, Sir C.V.: (1888-1970) Eminent Indian Scientist (F.R.S.) National Professor of Physics and founder Director of Raman Research Institute, Bangalore. He was awarded Nobel Prize for his discovery of ‘Raman Effect’ (Feb 28, 1928). His work on study of crystal structure is of unique importance. Feb 28 is celebrated every year as National Science Day.

Ramanujan, Srinivas: (1887-1920) Indian mathematician who contributed to the theory of numbers, theory of partitions, and the theory of continued fractions.

Ramsay, Sir William: (1852-1916) English chemist who discovered helium and later on neon, argon in collaboration with Rayleigh and others. He was awarded Nobel Prize in 1904.
Rao, Prof U. Ramachandra: is the Director of Indian Scientific Satellite Project (ISSP) at Peenya near Bangalore.

Ray, Sir P.C.: (1861-1944) founder of Indian Chemical Society and Bengal Chemical and Pharmaceutical Works Ltd., and author of ‘Hindu Chemistry’. His work about nitrous acid and its salts deserves special mention.

Richards, T.W.: He was Prof of Chemistry at Harvard University in U.S.A. He did notable  work in the accurate determination of atomic weights and was awarded Nobel Prize in 1916.

Roger Bacon: (1214-1294) He was inventor of Gun Powder and founder of experimental science; man of remarkable gifts and inventive power.

Rontgen, W. Konrad: (1845-1923) German physicist. He discovered X-rays, also called Rontgen rays. He was awarded the first Nobel Prize in 1901 for discovery of X-Rays.

Ross, Ronald: (1857-1932) leading British physician who discovered the cause of Malaria; awarded Nobel Prize for medicine in 1902.

Rutherford, Daniel: (1749-1819) a Scottish scientist who is given the credit for the discovery of nitrogen.

Rutherford, Lord: (1871-1937) won a Nobel Prize for his work on structure of atom and radio-activity.

Ryle, Sir Martin: of the U.K. who shared the 1974 Nobel Prize in Physics is known for the development of “aperture synthesis” technique designed to identify stellar objects through radio signals.

Saha, Dr Meghnad: (1893-1956) late Palit Prof of Physics, University College of Science and Technology, Calcutta University—well known for his researches in nuclear physics, cosmic rays, spectrum analysis and other branches of theoretical physics.

Sanger, Dr Frederik: British scientist awarded Nobel Prize in Chemistry in 1958 for his work in determining the composition of the insulin molecule. By his discovery he has put science a step forward towards knowing how disease attacks the human body. In 1980, he became only the fourth person ever to be awarded a second Nobel Prize.

Sarabhai, Dr Vikram A.: former Chairman of India’s Atomic Energy Commission and the Indian Space Research Organization (ISRO) died on December 30, 1971. Dr Sarabhai was an eminent physicist mainly interested in the astrophysical implications of Cosmic Ray Time Variations.

Sen, P.K. (Dr): is the Indian surgeon who performed Asia’s first heart transplant operation in Mumbai.

Simpson, Sir James Young: (1811-70) British physicist who was largely instrumental in the introduction of chloroform as an anaesthetic in 1847.

Soddy, Frederick: (1877-1956) British physical chemist. He was a pioneer of research into atomic disintegration. He coined the term “isotopes”;  did classic work on radioactivity.

Solvay, Earnest: (1838-1922) Belgian chemist known for devising a process known after his name for manufacture of sodium carbonate.

Susruta: was a fourth century Hindu surgeon and physician. He wrote an important  book on medicine and also a thesis on the medical properties of garlic.

Sutherland, Dr Earl W.: was the recipient of the Nobel Prize for Medicine, 1971.  He is credited with the discovery that the hormones in the human body produce another substance known as cyclic A.M.P., which activates them and controls the body’s cells. He has demonstrated that changes in the level of cyclic A.M.P. in the body can influence its disease-resisting capacity. This discovery opens up new vistas for the development of drugs that can treat diseases which have so far been regarded as incurable.

Teller, Edward (Dr): is a U.S. nuclear scientist who has played a major role in developing the hydrogen bomb. He is in fact known as the “father of the H-bomb”.

Thomson, Sir J.J.: (1856-1940) British physicist. He discovered the electron which inaugurated the electrical theory of the  atom. He is regarded as the founder of modern physics.

Tsiolkovsky: was a Russian teacher who in 1903 published a  treatise presenting remarkably accurate calculations on rocket dynamics and space-travel. He is looked upon as the earliest among the pioneers who laid the foundations of space exploration. The Russians call him the “Father of Rocketry”.

Varahmihira: (505-587) was a distinguished Indian astronomer, mathematician and philosopher. He was one of the nine gems of the court of king Vikramaditya.

Verne, Jules: (1828-1905) French science-fiction writer was author of “From the Earth to the Moon” published in 1865. The book carried a more or less accurate prediction of the launching and flight of Apollo-8.

Volta, A.: (1745-1827) Italian physicist and pioneer of electrical science; invented voltaic pile, the electrophorus and electroscope. The volt is named after him.

Voronoff, S.: Russian scientist best known for his method of preventing or delaying senility by grafting healthy animal glands, into the human body.

Watson and Crick: known for DNA double helix.

Watson-Watt, Sir Robert: British physicist. He developed radar.

Watt, James: (1736-1819) was Scottish engineer. He invented steam engine.

Yukawa, Dr H.: (born 1907) predicted a new particle meson which holds the protons and neutrons of the atomic nucleus. He is the first Japanese to win the Nobel Prize in Physics (1949).