Democritus (465 BC)
First to conceive matter in the form of particles, which he called atoms.
Alchemists (about 1000-1650)
Attempted to (1) change lead and other base metals to gold; (2) discover a universal solvent; and (3) discover a life-prolonging elixir. Used plant products and arsenic compounds to treat diseases.
Boyle, Sir Robert (1637-1691)
Formulated fundamental gas laws. First to conceive the possibility of small particles combining to form molecules; distinguished between compounds and mixtures; studied air and water pressures, desalination, crystals and electrical phenomena.
Priestley, Joseph (1733-1804)
Discovered oxygen, carbon monoxide and nitrous oxide.
Scheele, C.W. (1742-1786)
Discovered chlorine, tartaric acid, sensitivity of silver compounds to light (photochemistry); and oxidation of metals.
Le Blanc, Nicholas (1742-1806)
Invented a process for making soda ash from sodium sulfate, limestone and coal.
Lavoisier, A.L. (1743-1794)
Discovered nitrogen; studied acids and described composition of many organic compounds. Generally regarded as the father of chemistry.
Volta, A. (1745-1827)
Invented the electric battery, a series of “piles” or stacks of alternating layers of silver and zinc, or copper and zinc, separated by paper soaked in brine (electrolyte).
Berthollet, C.L. (1748-1822)
Corrected Lavoiserâ€™s theory of acids; discovered bleaching power of chlorine; studied combining weights of atoms (stoichiometry).
Jenner, Edward (1749-1823)
Discoverer of vaccination for prevention of smallpox (1776).
Dalton, John (1766-1844)
The first great chemical theorist; proposed atomic theory (1807);stated law of partial pressure of gases. His ideas led to laws of multiple proportions, constant composition and conservation of mass.
Avogadro, A. (1776-1856)
Proposed principle that equal volumes of gases contain the same number of molecules. The number (6.02 x 1023 for 22.41 litres of any gas) is a fundamental constant that applies to all chemical units.
Davy, Sir Humphry (1778-1829)
Laid foundation of electrochemistry, studied electroysis of salts in water and other electrochemical phenomena; isolated Na and K.
Gay-Lussac, J.L. (1778-1850)
Discovered boron and iodine, studied acids and bases and discovered indicators (litmus); improved production method for H2SO4, did basic research on behavior of gases versus temp and on the ratios of gas volumes in chemical reactions.
Berzelius, J.J. (1779-1850)
Classified minerals chemically; discovered and isolated many elements (Se, Th, Si, Ti, Zr); coined the terms isomer and catalyst; noted existence of radicals; anticipated discovery of colloids.
Faraday, Michael (1791-1867)
Extended Davyâ€™s work in electrochemistry. He developed theories of electrical and mechanical energy, electrolysis, corrosion, batteries, and electrometallurgy.
Wohler, F. (1800-1882)
First to synthesize an organic compound (urea, 1828) (a rearrangement reaction). This discovery was the beginning of synthetic organic chemistry.
Goodyear, Charles (1800-1860)
Discovered vulcanization of rubber (1844) by sulphur, inorganic accelerator, and heat. Hancock in England made a parallel discovery.
Liebig, J. von (1803-1873)
Fundamental investigation of plant life (photosynthesis) and soil chemistry; first to propose use of fertilisers. Discovered chloroform and cyanogen compounds.
Graham, Thomas (1822-1869)
Studied diffusion of solutions through membranes; established principles of colloid chemistry.
Pasteur, Louis (1822 – 1895)
(1) First to recognize infective bacteria as disease-causing agents; (2) developed concept of immunochemistry; (3) initiated heat-sterilization of wine and milk (pasteurization); (4) observed optical isomers (enantiomers) in tartaric acid.
Lister, Joseph (1827-1912)
Initiated use of antiseptics in surgery, e.g., phenols, carbolic acid, cresols.
KekulÃ©, A. (1829-1896)
Laid foundations of aromatic chemistry; conceived of four-valent carbon and structure of benzene ring; predicted isomeric substitutions (ortho-, meta-, para-).
Nobel, Alfred (1833-1896)
Invented dynamite, smokeless powder, blasting gelatin. Established international awards for achievements in chemistry, physics and medicine.
MendelÃ©ev, D.I. (1834-1907)
Discovered periodicity of the elements and compiled the first Periodic Table.
Hyatt, J.W. (1837-1920)
Initiated plastics industry (1869) by invention of Celluloid (nitrocellulose modified with camphor).
Perkin, Sir W.H. (1838-1907)
Synthesized first organic dye (mauveine, 1856) and first synthetic perfume (coumarin). His work on dyes was continued and expanded by Hofmann in Germany.
Beilstein, F.K. (1838-1906)
Compiled Handbuchder organischen Chemie, a multi-volume compendium of properties and reactions of organic chemicals.
Gibbs, Josiah W. (1839-1903)
Stated three principal laws of thermodynamics; expounded nature of entropy and phase rule and the relation between chemical, electric and thermal energy.
Chardonnet, H. (1839-1924)
First to produce a synthetic fibre (nitrocellulose) with properties similar to rayon.
Boltzmann, L. (1844-1906)
Developed kinetic theory of gases, their viscosity and diffusion properties are summarized in Boltzmannâ€™s Law.
Roentgen, W.K. (1845-1923)
Discovered x-radiation (1895). Awarded Nobel Prize in 1901.
Le Chatelier, H.L. (1850-1936)
Fundamental research on equilibrium reactions (Le Chatelierâ€™s Law),
combustion of gases, and metallurgy of iron and steel.
Becquerel, H. (1851-1908)
Discovered radioactivity, deflection of electrons by magnetic fields and gamma radiation. Nobel Prize 1903 (with the Curies).
Moisson, H. (1852- 907)
Developed electric furnace for making carbides and preparing pure
metals; isolated fluorine (1886). Nobel Prize 1906.
Fischer, Emil (1852-1919)
Basic research on sugars, purines, uric acid, enzymes, nitric acid, ammonia. Pioneer work in sterochemistry. Nobel Prize 1902.
Thomson, Sir J.J. (1856-1940)
Research on cathode rays resulted in proof of existence of electrons
(1896). Nobel Prize 1906.
Arrhenius, Svante (1859 – 1927)
Fundamental research on rates of reaction versus temperature, expressed by the Arrhenius equation; and on electrolytic dissociation. Nobel Prize 1903.
Hall, Charles Martin (1863-1914)
Invented method of aluminium manufacture by electrochemical reduction of alumina. Parallel discovery by Heroult in France.
Baekeland, Leo H. (1863-1944)
Invented phenolformaldehyde plastic (1907), the first completely synthetic resin (Bakelite).
Nernst, Walther Hermann (1864-1941)
Awarded Nobel Prize in 1920 for his work in thermochemistry, did basic research in electrochemistry and thermodynamics.
Werner, A. (1866-1919)
Introduced concept of coordination theory of valence (complex chemistry). Nobel Prize in 1913.
Curie, Marie (1867-1934)
Discovered and isolated radium; research on radioactivity of uranium. Nobel Prize 1903 (with Becquerel) in physics; in chemistry 1911.
Haber, F. (1868-1924)
Synthesized ammonia from nitrogen and hydrogen, the first industrial
fixation of atmospheric nitrogen (the process was further developed by Bosch). Nobel Prize 1918.
Rutherford, Sir Ernest (1871-1937)
First to prove radioactive decay of heavy elements and to carry out a
transmutation reaction (1919). Discovered half-life of radioactive elements. Nobel Prize 1908.
Lewis, Gilbert N. (1875-1946)
Proposed electron-pair theory of acids and bases; authority on thermodynamics.
Aston, F.W. (1877-1945)
Pioneer work on isotopes and their separation by mass spectrograph.
Nobel Prize 1922.
Fischer, Hans (1881-1945)
Basic research on porphyrins, chlorophyll, carotene, synthesized hemin. Nobel Prize 1930.
Langmuir, Irving (1881-1957)
Fundamental research on surface chemistry, monomolecular films, emulsion chemistry. Also electric discharges in gases, cloud seeding, etc. Nobel Prize 1932.
Staudinger, Hermann (1881-1965)
Fundamental research on high-polymer structure, catalytic synthesis, polymerization mechanisms, resulting eventually in development of stereospecific catalysts by Ziegler and Natta (stereoregular polymers). Nobel Prize 1963.
Flemming, Sir Alexander (1881-1955)
Discovered penicillin (1928); initiated antibiotics. Nobel Prize 1945. The science was developed in the U.S. by Selman A. Waksman.
Moseley, Henry G.J. (1887-1915)
discovered the relation between frequency of x-rays emitted by an element and its atomic number, thus indicating the elementâ€™s true position in the Periodic Table.
Adams, Roger (1889-1971)
Noted educator and contributor to industrial research in catalysis and structural analysis. Priestley Medal.
Midgley, Thomas (1889-1944)
Discovered tetraethyllead and antiknock treatment for gasoline (1921) and fluorocarbon refrigerants early research on synthetic rubber.
Ipatieff, Vladimir N. (1890-1952)
Basic research and development of catalytic alkylation and isomerisation of hydrocarbons (with Herman Pines).
Banting, Sir Frederick (1891-1941)
Isolated the insulin molecule. Nobel Prize 1923.
Chadwick, Sir James (1891-1974)
Discovered the neutron (1932) Nobel Prize 1935.
Urey, Harold C. (1894-1981)
Discovered heavy isotope of hydrogen (deuterium). Nobel Prize 1934. A leader of he Manhattan Project. Made original contributions to theories of the origin of the universe and of life processes.
Carothers, Wallace (1896-1937)
Polymerization research resulting in synthesis of neoprene (polychloroprene) and of nylon (polyamide).
Kistiakowsky, George B. (1900-1982)
Developed the detonating device used in first atomic bomb.
Heisenberg, W.K. (1901-1976)
Research in quantum mechanics resulting in development of the orbital theory of chemical bonding. Stated Uncertainity Principle. Nobel Prize 1932.
Fermi, Enrico (1901-1954)
First to achieve a controlled nuclear fission reaction (1939); basic research on subatomic particles. Nobel Prize 1938.
Lawrence, Ernest O. (1901-1958)
Invented the cyclotron in which first synthetic elements were created. Nobel Prize 1939.
Libby, Wilard F. (1908-1980)
Developed radiocarbn dating technique based on carbon-14. Nobel Prize 1960.
Crick, F.H.C (1916- ) with Watson, James D.
Elucidated structure of DNA molecule (1953) resulting in development of gene-splicing (recombinant DNA) techniques.
Woodward, Robert W. (1917-1979)
Nobel Prize 1965 for his brilliant syntheses of such compounds as cholesterol, quinine, chlorophyll and cobalamin.
The massif is divided into five channels that separate the Mediterranean climate zones in the north of the arid zone of the Sahara Desert to the south. Three of these channels are located in Morocco: High Atlas (covered with snow and visible in the lower left corner), the Middle Atlas (which appears as two spots of snow on the north-east of the High Atlas) and the Anti-Atlas (not visible here but located in the south-west of the High Atlas).
The High Atlas has the highest peaks in North Africa, including Mount Toubkal, which exceeds 4000 m altitude. Despite high temperatures of summer, these peaks remain snow cover for most of the year.
The Tellien Atlas and Saharan Atlas in Algeria are located (visible to the east of the Upper and Middle Atlas). The Atlas Tellien stretches along the Mediterranean coast and receives substantial rainfall which he was sheltering many fertile valleys. It extends to Tunisia (not shown here).
South AlgÃ©rien, below the Saharan Atlas (south of the Atlas Tellien) does so receives no precipitation and is part of the Sahara desert (which covers the lower part of the image).
Other elements are also visible in the image, including the Mediterranean Sea (top right) and the Atlantic Ocean (left), connected by the Straits of Gibraltar and the southern tip of Spain ( in the upper left).
This image was taken on 30 January 2009 by the camera Meris (Medium Resolution Imaging Spectrometer) Envisat working in full resolution mode, which allows to distinguish details of 300 m to the ground.
Preventing this condition is critical. Running, which is beneficial to health in general and the cardiovascular system in particular, has the drawbacks of increasing efforts on the joints of the leg. Researchers at the University of Virginia studied the stresses on the joint during running. Their surprising results show that running barefoot is best for the health of knees, hips and ankles, as running with running shoes. (more…)
The E-SWARM Marco Dorigo (IRIDIA-Faculty of Applied Sciences ULB) on the “swarm” ( “swarm intelligence“), a branch of artificial intelligence that deals with natural and artificial systems composed of many individuals which exhibit collective behavior due to control decentralized and self-organization. (more…)
Last December, the Mountain View giant has created Google and Energy has filed an application with the U.S. Commission of regulation of the energy (FERC) to obtain the status of merchant energy ( both producer and trader). Thus, the firm would be free to sell and purchase the electricity at the best price. (more…)
In 2002, the Earth Summit inJohannesburg,
governments committed themselves to halt the loss of biodiversity by 2010.This
mission seems far from the account … It is time to act drastically.
Large missions, including the CNRS is the instigator or partner, are being
launched across the globe, including locations of “hot spots” in the Amazon,
Africa, Madagascar, in the ocean, etc.. but also at the heart of our cities
where biodiversity is not just anecdotal.Meanwhile,
new approaches, including molecular, are developed to study biodiversity and
surprisingly, economists are now seriously consider the possibility of giving an
economic value to biodiversity, a concept hitherto highly taboo, and now
supported by the very France.
To mark the International Year of Biodiversity and the exit of the Journal of
the CNRS in January 2010 devoted to the rescue missions of biodiversity, CNRS
organized a press conference with the following presentations:
- Involvement of the CNRS in the year of biodiversity by Gaill, Scientific
Director of the Institute of Ecology and Environment Linking
- Biodiversity and conservation biology, by Robert Barbault, laboratory species
conservation, monitoring and restoration of populations (MNHN / CNRS / UPMC)
- Modeling of biodiversity, by Alain Pave, program director of the CNRS Amazon
- The economics of biodiversity, by Jean-Michel Salles, Montpellier Laboratory
of Theoretical and Applied Economics (University Montpellier Montpellier1/CNRS/INRA/ENSA)
- Events around the year of Biodiversity organized by the CNRS in 2010.
Rescuers of nature
In 2002, governments around the world pledged to halt the loss of biodiversity
are, and the goal is far from being achieved.It
is time to act drastically.One
thing is certain: the CNRS researchers are already working across the globe,
in Amazonian, Africa, the ocean … or even right in town! And in the labs,
all approaches from molecular biology to economics are being studied to better
understand the species and save them.As
we enter the International Year of Biodiversity decreed by the UN,the
newspaper of the CNRS provides a spotlight on these rescue missions of
The economic situation has always been unpredictable. A year ago, who could say with a certain degree of clarity that the world will cover the economic crisis of epic proportions? But he came, and we must do everything possible both at the individual level and at the corporate level.
How can companies cope with the economic crisis? What steps they are taking to protect market share, retain talent, and perhaps even use the situation to expand their business?
To answer these questions, we must understand that the key to the survival of the company are selling. The Company may, to some extent to cut costs, but no sales sooner or later the money will end and the company closes. Some company organizes trade show displays. Products or services must be sold to generate a turnover of money, which, in turn, will pay salaries, employment, etc.
I read in the always interesting blog Maikelnai surprising news, and still further complicates the understanding of our universe. If the terms dark matter, black hole or wormhole seem far away, a new concept is added to the list, the “dark flow.”I have discovered a group of astrophysicists from NASA and have defined a very “simple” is something that is beyond the observable universe, and that has an effect on the observable.
At the moment we can only speculate about the nature of this material, where it is believed that space-time in these regions of space could be very different, and probably does not contain stars and galaxies but massive structures, giant, much larger than any thing of our own observable universe. Due to the gravitational attraction exerted these giant structures, could draw the groups of galaxies causing the dark flow.Apparently, this concept can give much play in the next few years helping to explain the motion of our universe and the interactions “invisible” that govern it
The transfer of resources, through trade, gifts or grants, for example, could prevent up to nine out of ten wars in some kind of war, according to a study by researchers at the Universidad Carlos III de Madrid (UC3M).Economists who have developed this research are interested in how to avoid war when there is a body that ensures compliance with peace treaties like the UN. In this case, all countries can do is to transfer resources (through trade agreements, gifts, grants, etc..) And hope that once made this transfer, no one has incentives to start a conflict. “We found that when wars are due to unequal resources in the vast majority of cases, transfers to avoid war,” explains Luis CorchÃ³n professor, Department of Economics UC3M, which has published the study with Professor at the Autonomous University of Barcelona, Carmen Bevia, in Games and Economic Behavior, the journal in economic theory has a greater impact in the Social Sciences Citation Index, as reported last year.
To give an idea of how well it works this mechanism, researchers have conducted a series of scenarios that calculate the probability of occurrence of a war. “Without transfer – details – is 38.6 percent, whereas transfers decreases to 4.6 percent, as can be deduced that eliminates transfers 88 per cent of disputes,” they conclude. In other types of war, however, this mechanism is not as useful. For example, when the probability of winning the war does not depend almost no resources, poor incentives to attack the country are so great that there is no way to make it peaceful, they say. Or, conversely, when the odds of winning the war are heavily dependent on resources, there is no way to stop the attack the most powerful country. “In short – resume CorchÃ³n Professor – our work sets limits on the policies of appeasement and illustrates that in many cases it is necessary to have a third power to impose peace, because the negotiations between the countries in the field of cross can stop the aggression “.
Types of war
The study authors studied the war from the point of view of rational decision, regardless of outside elements into economic theory and that may be important in understanding its origin, such as religion, ethnic conflicts or emotional or historical reasons. In this context, they found that there are three fundamental causes of armed conflict: resource inequality, that the outcome of war is not very dependent on the material and military superiority of the economically most powerful country. In the first two cases its usually gives the paradox that the poorest countries are those that start the war, despite the probability that the gain is relatively small. This trend of relatively weak countries to start wars and lose them as was noted by Adam Smith and Carl von Clausewitz and is known as the paradox of the contests between unequal countries ( “uneven contenders paradox”), the researchers note.
This study is part of a research program on the impact and origins of conflict over resource allocation. The authors analyze the economic causes of conflict and suggest ways to avoid them. “If you do not take into account emotional factors, ethnic or religious strife are many that can be explained simply as movements of rational actors pursuing their own interests, essentially material, as resources, mines, people, fertile land … – Notes Luis CorchÃ³n -. The greatest achievement of this theory of the contests – ongoing – is to make us understand that a society in which all actors are rational can be self-defeating. “
The epidemic of influenza devastating 1918 by the similarity of viruses with the A (H1N1) by the pandemic now, remember our good memories. A new article suggests that the aspirin may partly explain the high number of deaths has caused what at the time. Published in Clinical Infectious Diseases, the article sounds like a warning.
In 1918, the use of aspirin, promoted by the pharmaceutical industry, has been approved by doctors who wanted to act, and accepted by families and institutions with much needed hope. At the time, doctors do not know yet completely Pharmacology and dosage of aspirin.
High dose aspirin had been used to administer to patients is now known for its toxicity in some cases and may cause a dangerous buildup of fluid in the lungs. These effects may have contributed to the incidence and severity of symptoms at the onset of bacterial infections and high mortality. Autopsy reports from 1918 are consistent with what we now know the dangers of aspirin. Karen Starko, the author of the study, said that “drugs can save people and improve our lives. Must still be ever mindful of the importance of strength, the balance between benefits and risks and limitations of our knowledge. “