موسوعة العلمـاء و المخترعين .. العلمـاء بالترتيب حسب اسم الشهرة .. الحرف د

Encyclopedia of Scientists and Inventors.. Scientists in order according to their nickname.. The letter d

⏹ Darbo, Jean Gaston
Jean-Gaston Darboux

French mathematician (1842 - 1917)
Darbo was educated in Paris and held a number of teaching positions, including a chair in geometry at the Sorbonne. Darbo was a foreign fellow of the British Royal Society.
His works on differential equations, to which he introduced a new method of differentiation, were famous, as well as his works on infinite geometry.

Dawson, Clinton Joseph
Davisson, Clinton Joseph

American physicist (1881-1958)
Dufson was educated in Chicago and Princeton.
He taught physics at Princeton before turning to industrial studies at Bell Telephone Laboratories.
Daveson conducted outstanding research on magnetism, electricity and energy radiation - during his research in 1927 with Germer, they discovered the phenomenon of refractive return of electrons by crystals, and in 1937 he shared the Nobel Prize for Physics with Thomson.

⏹ Daron, Charles Robert
Darwin Charles Robert

English naturalist (1809-1882)
Darwin was educated in Edinburgh and Cambridge. He participated in the Beagle expedition, which made its voyage around the world in 1831. As a naturalist on board the ship, his studies and observations were the basis on which he based his works in natural history, which he collected in a book he published in 1859 entitled: The Origin of Species by Selection is Natural. Origin of Species by Natural Selection
. It included his famous theory of evolution, which was a revolution in biology, especially with regard to man.
Darwin was subject to severe criticism and attack.
However, his theory, with a slight modification, and after a huge effort of evangelism, was accepted by his student and contemporary, Thomas Huxley T. Darwin also developed his theory of sexual selection and pointed out that man is from the same group that the chimpanzee descends from. This appeared in Descent of Man 1871.
Darwin's works and opinions led to freeing biology from the dominance of (metaphysical) speculation and developing it into a science based on observation and experiment.
One of his well-known books is Animal Science.
Voyage of the Beagle in 1840. Zoology of the Voyage of the Beagle
Fertilization of orchids in 1862.
The Fertilization of Orchids
The change of plants and animals by domestication in 1867.
The Variation of Plants and Animals under Domestication.
Four of Darwin's five children were able to achieve a distinguished scientific position for themselves.

⏹ Dahl, Anders

Swedish botanist (from the eighteenth century) •
Dahl emerged as a brilliant student of Linnaeus (1707 to 1778) and entered the scientists' record for his achievements in the study of plants. There are flowers bearing his name, which are the genus Dahlia.

⏹ Dalanbier, Jean d'Alambert, Jean

See Alembert, Jean le Rond d '.

⏹ Dalton, John Dalton,

English chemist (1766 - 1844) ·
Dalton grew up in a poor environment, so he worked as a worker on a farm and then participated with his brother in opening a school in «Kendall» (Kendall), and thus had the opportunity for Dalton to read the works of Isaac Newton, and after extensive studies in the properties of gases, Dalton put his atomic theory, which forms the basis of the theory Modern chemical.
Dalton considered that the atom is indivisible. Dalton was the first to study the change in vapor pressure with the change in temperature. He also developed the law of multiple proportions in chemical reactions and discovered the law that bears his name: “Dalton’s Law”, which states that the saturated vapor pressure of any liquid takes the same value at Evenly displaced temperatures from the boiling points of those liquids. Dalton was the first to measure the rise in air temperature as a result of pressure (in a confined space). Dalton also assumed that all gases can be liquefied at high pressures and low temperatures. Dalton has verified the electrical nature of the aurora borealis, and he wrote a famous book entitled: A New System of Chemical Philosophy.
Dalton worked as a professor of mathematics and natural sciences at New College in Manchester, and there he put the first description of Daltonism or color blindness, which was a common condition between Dalton and his brother.

⏹ Dalén, Nils Gustav

Swedish physicist and engineer (1869-1937)
Dalen learned in Göteborg and Zurich, then became an inventor and an expert in the use of gas. He invented self-lighting for uninhabited beacons and railway signals.
During his experiments, an explosion occurred that made him lose his sight, but despite that, he continued with full confidence in his scientific activity and in his studies until his death.
He won the Nobel Prize for Physics in 1912, one year before the accident.