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Maria Bakunin
Maria Mikhailovna Bakunina (russian: Мария Михайловна Бакунина; 1873–1960) was a Russian-Italian chemist and geologist. Born in Siberia, she moved to southern Italy at a young age, taking up chemistry during her education. By the time of her graduation from the University of Naples, she was already a pioneering figure in stereochemistry and made a number of advancements in applied chemistry. During the early 20th century, she carried out a series of geological surveys in the region of Campania, identifying a number of ichthyol deposits for exploitation. With the outbreak of World War II, she continued her work at the University of Naples and dedicated herself to the rebuilding of the Accademia Pontaniana after the war. Early life and education On 2 February 1873, Maria Bakunin was born in the Siberian city of Krasnoyarsk. The third child of Russian anarchist Mikhail Bakunin, after he father died in 1876, she and her family moved to Naples, where they had ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krasnoyarsk
Krasnoyarsk ( ; rus, Красноя́рск, a=Ru-Красноярск2.ogg, p=krəsnɐˈjarsk) (in semantic translation - Red Ravine City) is the largest city and administrative center of Krasnoyarsk Krai, Russia. It is situated along the Yenisey River, and is the second-largest city in Siberia after Novosibirsk, with a population of over 1.1 million. Krasnoyarsk is an important junction of the renowned Trans-Siberian Railway, and is one of the largest producers of aluminium in the country. The city is known for its natural landscape; author Anton Chekhov judged Krasnoyarsk to be the most beautiful city in Siberia. The Stolby Nature Sanctuary is located 10 km south of the city. Krasnoyarsk is a major educational centre in Siberia, and hosts the Siberian Federal University. In 2019, Krasnoyarsk was the host city of the 2019 Winter Universiade, the third hosted in Russia. Geography The total area of the city, including suburbs and the river, is .Poexaly.ru. Krasnoyars ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. World War II was a total war that directly involved more than 100 million personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the only two nuclear weapons ever used in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, mostly among civilians. Tens of millions died due to genocides (including the Holocaust), starvation, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Map
A geologic map or geological map is a special-purpose map made to show various geological features. Rock units or geologic strata are shown by color or symbols. Bedding planes and structural features such as faults, folds, are shown with strike and dip or trend and plunge symbols which give three-dimensional orientations features. Stratigraphic contour lines may be used to illustrate the surface of a selected stratum illustrating the subsurface topographic trends of the strata. Isopach maps detail the variations in thickness of stratigraphic units. It is not always possible to properly show this when the strata are extremely fractured, mixed, in some discontinuities, or where they are otherwise disturbed. Symbols Lithologies Rock units are typically represented by colors. Instead of (or in addition to) colors, certain symbols can be used. Different geologic mapping agencies and authorities have different standards for the colors and symbols to be used for rocks of diff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Vesuvius
Mount Vesuvius ( ; it, Vesuvio ; nap, 'O Vesuvio , also or ; la, Vesuvius , also , or ) is a somma-stratovolcano located on the Gulf of Naples in Campania, Italy, about east of Naples and a short distance from the shore. It is one of several volcanoes forming the Campanian volcanic arc. Vesuvius consists of a large cone partially encircled by the steep rim of a summit caldera, resulting from the collapse of an earlier, much higher structure. The eruption of Mount Vesuvius in AD 79 destroyed the Roman cities of Pompeii, Herculaneum, Oplontis, Stabiae, and several other settlements. The eruption ejected a cloud of stones, ashes and volcanic gases to a height of , erupting molten rock and pulverized pumice at the rate of per second. More than 1,000 people are thought to have died in the eruption, though the exact toll is unknown. The only surviving eyewitness account of the event consists of two letters by Pliny the Younger to the historian Tacitus. Vesuvius has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stanislao Cannizzaro
Stanislao Cannizzaro ( , also , ; 13 July 1826 – 10 May 1910) was an Italian chemist. He is famous for the Cannizzaro reaction and for his influential role in the atomic-weight deliberations of the Karlsruhe Congress in 1860. Biography Cannizzaro was born in Palermo in 1826. He entered the university there with the intention of making medicine his profession, but he soon turned to the study of chemistry. In 1845 and 1846, he acted as assistant to Raffaele Piria (1815–1865), known for his work on salicin, and who was then professor of chemistry at Pisa and subsequently occupied the same position at Turin. During the Sicilian revolution of independence of 1848, Cannizzaro served as an artillery officer at Messina and was also chosen deputy for Francavilla in the Sicilian parliament; and, after the fall of Messina in September 1848, he was stationed at Taormina. On the collapse of the insurgents, Cannizzaro escaped to Marseille in May 1849, and, after visiting various ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus Pentoxide
Phosphorus pentoxide is a chemical compound with molecular formula P4 O10 (with its common name derived from its empirical formula, P2O5). This white crystalline solid is the anhydride of phosphoric acid. It is a powerful desiccant and dehydrating agent. Structure Phosphorus pentoxide crystallizes in at least four forms or polymorphs. The most familiar one, a metastable form (shown in the figure), comprises molecules of P4O10. Weak van der Waals forces hold these molecules together in a hexagonal lattice (However, in spite of the high symmetry of the molecules, the crystal packing is not a close packing). The structure of the P4O10 cage is reminiscent of adamantane with ''T''d symmetry point group. It is closely related to the corresponding anhydride of phosphorous acid, P4O6. The latter lacks terminal oxo groups. Its density is 2.30 g/cm3. It boils at 423 °C under atmospheric pressure; if heated more rapidly it can sublimate. This form can be made by condensing the vap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bologna
Bologna (, , ; egl, label= Emilian, Bulåggna ; lat, Bononia) is the capital and largest city of the Emilia-Romagna region in Northern Italy. It is the seventh most populous city in Italy with about 400,000 inhabitants and 150 different nationalities. Its metropolitan area is home to more than 1,000,000 people. It is known as the Fat City for its rich cuisine, and the Red City for its Spanish-style red tiled rooftops and, more recently, its leftist politics. It is also called the Learned City because it is home to the oldest university in the world. Originally Etruscan, the city has been an important urban center for centuries, first under the Etruscans (who called it ''Felsina''), then under the Celts as ''Bona'', later under the Romans (''Bonōnia''), then again in the Middle Ages, as a free municipality and later ''signoria'', when it was among the largest European cities by population. Famous for its towers, churches and lengthy porticoes, Bologna has a well-preserved ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Syntheses
''Organic Syntheses'' is a peer-reviewed scientific journal that was established in 1921. It publishes detailed and checked procedures for the synthesis of organic compounds. A unique feature of the review process is that all of the data and experiments reported in an article must be successfully repeated in the laboratory of a member of the editorial board as a check for reproducibility prior to publication. The journal is published by Organic Syntheses, Inc., a non-profit corporation. An annual print version is published by John Wiley & Sons on behalf of Organic Syntheses, Inc. History Prior to World War I, work on synthetic organic chemistry in the United States had been quite limited, and most of the reagents used in laboratories had to be imported from Europe. When export stoppages and trade embargoes cut off this source, Clarence Derick, a professor of chemistry at University of Illinois at Urbana-Champaign, began an effort to synthesize these needed chemicals in industr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colloid
A colloid is a mixture in which one substance consisting of microscopically dispersed insoluble particles is suspended throughout another substance. Some definitions specify that the particles must be dispersed in a liquid, while others extend the definition to include substances like aerosols and gels. The term colloidal suspension refers unambiguously to the overall mixture (although a narrower sense of the word ''suspension'' is distinguished from colloids by larger particle size). A colloid has a dispersed phase (the suspended particles) and a continuous phase (the medium of suspension). The dispersed phase particles have a diameter of approximately 1 nanometre to 1 micrometre. Some colloids are translucent because of the Tyndall effect, which is the scattering of light by particles in the colloid. Other colloids may be opaque or have a slight color. Colloidal suspensions are the subject of interface and colloid science. This field of study was introduced in 1845 by Itali ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenols
In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of one or more hydroxyl groups (— O H) bonded directly to an aromatic hydrocarbon group. The simplest is phenol, . Phenolic compounds are classified as simple phenols or polyphenols based on the number of phenol units in the molecule. Phenols are both synthesized industrially and produced by plants and microorganisms. Properties Acidity Phenols are more acidic than typical alcohols. The acidity of the hydroxyl group in phenols is commonly intermediate between that of aliphatic alcohols and carboxylic acids (their pKa is usually between 10 and 12). Deprotonation of a phenol forms a corresponding negative phenolate ion or phenoxide ion, and the corresponding salts are called phenolates or phenoxides (aryloxides according to the IUPAC Gold Book). Condensation with aldehydes and ketones Phenols are susceptible to Electrophilic aromatic substitutions. Condensation with formald ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ester
In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. They perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties. '' Nomenclature Etymology Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picrotoxin
Picrotoxin, also known as cocculin, is a poisonous crystalline plant compound. It was first isolated by the French pharmacist and chemist Pierre François Guillaume Boullay (1777–1869) in 1812. The name "picrotoxin" is a combination of the Greek words "picros" (bitter) and "toxicon" (poison). A mixture of two different compounds, picrotoxin occurs naturally in the fruit of the ''Anamirta cocculus'' plant, although it can also be synthesized chemically. Due to its interactions with the inhibitory neurotransmitter GABA, picrotoxin acts as a stimulant and convulsant. It mainly impacts the central nervous system, causing seizures and respiratory paralysis in high enough doses. Chemical structure and synthesis Picrotoxin is an equi molar mixture of two compounds, picrotoxinin (C15H16O6; CAS# 17617-45-7) and picrotin (C15H18O7; CAS# 21416-53-5). Of the two compounds, picrotin is less active. Picrotoxin occurs naturally in the fruit of the ''Anamirta cocculus'', a climbing plant fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
