Émile Henriot (chemist)

	Émile Henriot (chemist) Émile Henriot (2 July 1885–1 February 1961) was a French chemist notable for being the first to show definitively that potassium and rubidium are naturally radioactive. He investigated methods to generate extremely high angular velocities, and found that suitably placed air-jets can be used to spin tops at very high speeds—this technique was later used to construct ultracentrifuges. He was a pioneer in the study of the electron microscope. He also studied birefringence and molecular vibrations. He obtained his DSc in physics in 1912 the Sorbonne, Paris, under Marie Curie Maria Salomea Skłodowska-Curie (; ; 7 November 1867 – 4 July 1934), known simply as Marie Curie ( ; ), was a Polish and naturalised-French physicist and chemist who conducted pioneering research on radioactivity. She was List of female .... As a professor at the Free University of Brussels he attended the Solvay Conferences of 1924, 1927, 1930, 1933, 1948, 1951 and 1954. For many of the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Solvay Conference The Solvay Conferences () have been devoted to preeminent unsolved problems in both physics and chemistry. They began with the historic invitation-only 1911 Solvay Conference on Physics, considered a turning point in the world of physics, and are ongoing. Since the success of 1911, they have been organised by the International Solvay Institutes for Physics and Chemistry, founded by the Belgian industrialist Ernest Solvay in 1912 and 1913, and located in Brussels. The institutes coordinate conferences, workshops, seminars, and colloquia. Recent Solvay Conferences entail a three year cycle: the Solvay Conference on Physics followed by a gap year, followed by the Solvay Conference on Chemistry. The 1st Solvay Conference on Biology titled "The organisation and dynamics of biological computation" took place in April 2024. Notable conferences First conference Hendrik Lorentz was chairman of the first Solvay Conference on Physics, held in Brussels from 30 October to 3 November ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Electron Microscope An electron microscope is a microscope that uses a beam of electrons as a source of illumination. It uses electron optics that are analogous to the glass lenses of an optical light microscope to control the electron beam, for instance focusing it to produce magnified images or electron diffraction patterns. As the wavelength of an electron can be up to 100,000 times smaller than that of visible light, electron microscopes have a much higher Angular resolution, resolution of about 0.1 nm, which compares to about 200 nm for optical microscope, light microscopes. ''Electron microscope'' may refer to: * Transmission electron microscopy, Transmission electron microscope (TEM) where swift electrons go through a thin sample * Scanning transmission electron microscopy, Scanning transmission electron microscope (STEM) which is similar to TEM with a scanned electron probe * Scanning electron microscope (SEM) which is similar to STEM, but with thick samples * Electron microprobe sim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	University Of Paris Alumni A university () is an institution of tertiary education and research which awards academic degrees in several academic disciplines. ''University'' is derived from the Latin phrase , which roughly means "community of teachers and scholars". Universities typically offer both undergraduate and postgraduate programs. The first universities in Europe were established by Catholic monks. The University of Bologna (), Italy, which was founded in 1088, is the first university in the sense of: being a high degree-awarding institute. using the word (which was coined at its foundation). having independence from the ecclesiastic schools and issuing secular as well as non-secular degrees (with teaching conducted by both clergy and non-clergy): grammar, rhetoric, logic, theology, canon law and notarial law.Hunt Janin: "The university in medieval life, 1179–1499", McFarland, 2008, , p. 55f.de Ridder-Symoens, Hilde''A History of the University in Europe: Volume 1, Universities i ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu]
picture info	1961 Deaths Events January * January 1 – Monetary reform in the Soviet Union, 1961, Monetary reform in the Soviet Union. * January 3 United States President Dwight D. Eisenhower announces that the United States has severed diplomatic and consular relations with Cuba (Cuba–United States relations are restored in 2015). Aero Flight 311 (Koivulahti air disaster): Douglas DC-3C OH-LCC of Finnish airline Finnair, Aero crashes near Kvevlax (Koivulahti), on approach to Vaasa Airport in Finland, killing all 25 on board, due to pilot error: an investigation finds that the Captain (civil aviation), captain and First officer (civil aviation), first officer were both exhausted for lack of sleep, and had consumed excessive amounts of alcohol at the time of the crash. It remains the deadliest air disaster to occur in the country. * January 5 Italian sculptor Alfredo Fioravanti enters the U.S. Consulate in Rome, and confesses that he was part of the team that forged the Etruscan terra ... [...More Info...] [...Related Items...] OR:** [Wikipedia] [Google] [Baidu]
picture info	1885 Births Events January * January 3– 4 – Sino-French War – Battle of Núi Bop: French troops under General Oscar de Négrier defeat a numerically superior Qing Chinese force, in northern Vietnam. * January 17 – Mahdist War in Sudan – Battle of Abu Klea: British troops defeat Mahdist forces. * January 20 – American inventor LaMarcus Adna Thompson patents a roller coaster. * January 24 – Irish rebels damage Westminster Hall and the Tower of London with dynamite. * January 26 – Mahdist War in Sudan: Troops loyal to Mahdi Muhammad Ahmad conquer Khartoum; British commander Charles George Gordon is killed. February * February 5 – King Leopold II of Belgium establishes the Congo Free State, as a personal possession. * February 9 – The first Japanese arrive in Hawaii. * February 16 – Charles Dow publishes the first edition of the Dow Jones Industrial Average. The index stands at a level of 62.76, and r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Nature (journal) ''Nature'' is a British weekly scientific journal founded and based in London, England. As a multidisciplinary publication, ''Nature'' features Peer review, peer-reviewed research from a variety of academic disciplines, mainly in science and technology. It has core editorial offices across the United States, continental Europe, and Asia under the international scientific publishing company Springer Nature. ''Nature'' was one of the world's most cited scientific journals by the Science Edition of the 2022 ''Journal Citation Reports'' (with an ascribed impact factor of 50.5), making it one of the world's most-read and most prestigious academic journals. , it claimed an online readership of about three million unique readers per month. Founded in the autumn of 1869, ''Nature'' was first circulated by Norman Lockyer and Alexander MacMillan (publisher), Alexander MacMillan as a public forum for scientific innovations. The mid-20th century facilitated an editorial expansion for the j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Université Libre De Bruxelles The (French language, French, ; lit. Free University of Brussels; abbreviated ULB) is a French-speaking research university in Brussels, Belgium. It has three campuses: the ''Solbosch'' campus (in the City of Brussels and Ixelles), the ''Plaine'' campus (in Ixelles) and the ''Erasmus'' campus (in Anderlecht). The Université libre de Bruxelles was formed in 1969 by the splitting of the Free University of Brussels (1834–1969), Free University of Brussels, which was founded in 1834 by the lawyer and Liberalism, liberal politician Pierre-Théodore Verhaegen. The founder aimed to establish a university independent from state and church, where academic freedom would prevail. This is still reflected in the university's motto , or "Conquering darkness through science". One of the leading Belgian universities open to Europe and the world, the ULB now has about 24,200 students, 33% of whom come from abroad, and an equally cosmopolitan staff. Name Brussels has two universities whose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of cities in the European Union by population within city limits, fourth-most populous city in the European Union and the List of cities proper by population density, 30th most densely populated city in the world in 2022. Since the 17th century, Paris has been one of the world's major centres of finance, diplomacy, commerce, culture, Fashion capital, fashion, and gastronomy. Because of its leading role in the French art, arts and Science and technology in France, sciences and its early adoption of extensive street lighting, Paris became known as the City of Light in the 19th century. The City of Paris is the centre of the Île-de-France region, or Paris Region, with an official estimated population of 12,271,794 inhabitants in January 2023, or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Birefringence Birefringence, also called double refraction, is the optical property of a material having a refractive index that depends on the polarization and propagation direction of light. These optically anisotropic materials are described as birefringent or birefractive. The birefringence is often quantified as the maximum difference between refractive indices exhibited by the material. Crystals with non-cubic crystal structures are often birefringent, as are plastics under mechanical stress. Birefringence is responsible for the phenomenon of double refraction whereby a ray of light, when incident upon a birefringent material, is split by polarization into two rays taking slightly different paths. This effect was first described by Danish scientist Rasmus Bartholin in 1669, who observed it in Iceland spar (calcite) crystals which have one of the strongest birefringences. In the 19th century Augustin-Jean Fresnel described the phenomenon in terms of polarization, understanding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Ultracentrifuges An ultracentrifuge is a centrifuge optimized for spinning a rotor at very high speeds, capable of generating acceleration as high as (approx. ). There are two kinds of ultracentrifuges, the preparative and the analytical ultracentrifuge. Both classes of instruments find important uses in molecular biology, biochemistry, and polymer science.Susan R. Mikkelsen & Eduardo Cortón. Bioanalytical Chemistry, Ch. 13. Centrifugation Methods. John Wiley & Sons, Mar 4, 2004, pp. 247-267. History In 1924 Theodor Svedberg built a centrifuge capable of generating 7,000 g (at 12,000 rpm), and called it the ultracentrifuge, to juxtapose it with the Ultramicroscope that had been developed previously. In 1925-1926 Svedberg constructed a new ultracentrifuge that permitted fields up to 100,000 g (42,000 rpm). Modern ultracentrifuges are typically classified as allowing greater than 100,000 g. Svedberg won the Nobel Prize in Chemistry in 1926 for his research on colloids and proteins using the ultrace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Besançon Besançon (, ; , ; archaic ; ) is the capital of the Departments of France, department of Doubs in the region of Bourgogne-Franche-Comté. The city is located in Eastern France, close to the Jura Mountains and the border with Switzerland. Capital of the historic and cultural region of Franche-Comté, Besançon is home to the Bourgogne-Franche-Comté regional council headquarters, and is an important administrative centre in the region. It is also the seat of one of the fifteen French ecclesiastical provinces and one of the two 1st Armored Division (France), divisions of the French Army. In 2022 the city had a population of 120,057, in a metropolitan area of 284,474, the second in the region in terms of population. Established in a meander of the river Doubs (river), Doubs, the city was already important during the Gallo-Roman era under the name of ''Vesontio'', capital of the Sequani. Its geography and specific history turned it into a military stronghold, a garrison city, a p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Rubidium Rubidium is a chemical element; it has Symbol (chemistry), symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher than Properties of water, water. On Earth, natural rubidium comprises two isotopes: 72% is a stable isotope Rb, and 28% is slightly radioactive Rb, with a half-life of 48.8 billion years – more than three times as long as the estimated age of the universe. German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed technique, Atomic emission spectroscopy#Flame emission spectroscopy, flame spectroscopy. The name comes from the Latin word , meaning deep red, the color of its emission spectrum. Rubidium's compounds have various chemical and electronic applications. Rubidium metal is easily vaporized and has a convenient spectral absorption range, making it a frequent target for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]