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Nencki
Wilhelm Marceli Nencki (15 January 1847 in Boczki, Zduńska Wola County – 14 October 1901 in Saint Petersburg) was a Polish chemist and doctor. Work Nencki's main scientific interest concentrated on urea synthesis, the chemistry of purines and biological oxidation of aromatic compounds. He was also interested in the structure of proteins, enzymatic processes in the intestine and bacterial biochemistry. One of his achievements was for example demonstration that urea is formed in the organism from amino acids rather than being preformed on a protein molecule and that it is accompanied by binding of carbon dioxide. He proposed that the synthesis of fatty acids proceeds stepwise, by a gradual condensation of two-carbon-atom fragments and that oxidation of fatty acids occurs by splitting into two-carbon units. In 1877 while working at the University of Berne he discovered rhodanine via a reaction between ammonium rhodanide (in modern chemistry ammonium thiocyanate) and chloroace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nencki
Wilhelm Marceli Nencki (15 January 1847 in Boczki, Zduńska Wola County – 14 October 1901 in Saint Petersburg) was a Polish chemist and doctor. Work Nencki's main scientific interest concentrated on urea synthesis, the chemistry of purines and biological oxidation of aromatic compounds. He was also interested in the structure of proteins, enzymatic processes in the intestine and bacterial biochemistry. One of his achievements was for example demonstration that urea is formed in the organism from amino acids rather than being preformed on a protein molecule and that it is accompanied by binding of carbon dioxide. He proposed that the synthesis of fatty acids proceeds stepwise, by a gradual condensation of two-carbon-atom fragments and that oxidation of fatty acids occurs by splitting into two-carbon units. In 1877 while working at the University of Berne he discovered rhodanine via a reaction between ammonium rhodanide (in modern chemistry ammonium thiocyanate) and chloroace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhodanine
Rhodanine is a 5-membered heterocyclic organic compound possessing a thiazolidine core. It was discovered in 1877 by Marceli Nencki who named it ''"Rhodaninsaure"'' in reference to its synthesis from ammonium rhodanide (known as ammonium thiocyanate to modern chemists) and chloroacetic acid in water. Rhodanines can also be prepared by the reaction of carbon disulfide, ammonia, and chloroacetic acid, which proceeds via an intermediate dithiocarbamate In organic chemistry, a dithiocarbamate is a functional group with the general formula and structure . It is the analog of a carbamate in which both oxygen atoms are replaced by sulfur atoms (when only 1 oxygen is replaced the result is thioca .... : Derivatives Some rhodanine derivatives have pharmacological properties; for instance, epalrestat is used to treat diabetic neuropathy. However, most are promiscuous binders with poor selectivity; as a result, this class of compounds is viewed with suspicion by medicinal chemis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boczki, Zduńska Wola County
Boczki is a village in the administrative district of Gmina Szadek, within Zduńska Wola County, Łódź Voivodeship, in central Poland. It lies approximately west of Szadek, north-west of Zduńska Wola, and west of the regional capital Łódź Łódź, also rendered in English as Lodz, is a city in central Poland and a former industrial centre. It is the capital of Łódź Voivodeship, and is located approximately south-west of Warsaw. The city's coat of arms is an example of canti .... Notable residents * Wilhelm Marceli Nencki (1847–1901), chemist and doctor References Villages in Zduńska Wola County {{ZduńskaWola-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leon Marchlewski
Leon Paweł Teodor Marchlewski (15 December 1869 in Włocławek – 16 January 1946 in Kraków, Poland) was a Polish chemist and an Honorary Member of the Polish Chemical Society. He was one of the founders in the field of chlorophyll chemistry Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions .... The illustration on the right is of his diplomatic passport he used in 1927 to attend an international conference on chemistry in Paris. References External links * 1869 births 1946 deaths Burials at Rakowicki Cemetery People from Włocławek Polish senators Polish chemists Chemical pathologists Members of the Lwów Scientific Society Rectors of the Jagiellonian University Commanders of the Order of Polonia Restituta People from Congress Poland {{Chemist-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haemoglobin
Hemoglobin (haemoglobin BrE) (from the Greek word αἷμα, ''haîma'' 'blood' + Latin ''globus'' 'ball, sphere' + ''-in'') (), abbreviated Hb or Hgb, is the iron-containing oxygen-transport metalloprotein present in red blood cells (erythrocytes) of almost all vertebrates (the exception being the fish family Channichthyidae) as well as the tissues of some invertebrates. Hemoglobin in blood carries oxygen from the respiratory organs (''e.g.'' lungs or gills) to the rest of the body (''i.e.'' tissues). There it releases the oxygen to permit aerobic respiration to provide energy to power functions of an organism in the process called metabolism. A healthy individual human has 12to 20grams of hemoglobin in every 100mL of blood. In mammals, the chromoprotein makes up about 96% of the red blood cells' dry content (by weight), and around 35% of the total content (including water). Hemoglobin has an oxygen-binding capacity of 1.34mL O2 per gram, which increases the total blood oxygen ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloroacetic Acid
Chloroacetic acid, industrially known as monochloroacetic acid (MCA), is the organochlorine compound with the formula ClCH2CO2H. This carboxylic acid is a useful building block in organic synthesis. It is a colorless solid. Related compounds are dichloroacetic acid and trichloroacetic acid. Production Chloroacetic acid was first prepared (in impure form) by the French chemist Félix LeBlanc (1813–1886) in 1843 by chlorinating acetic acid in the presence of sunlight, and in 1857 (in pure form) by the German chemist Reinhold Hoffmann (1831–1919) by refluxing glacial acetic acid in the presence of chlorine and sunlight, and then by the French chemist Charles Adolphe Wurtz by hydrolysis of chloroacetyl chloride (ClCH2COCl), also in 1857. Chloroacetic acid is prepared industrially by two routes. The predominant method involves chlorination of acetic acid, with acetic anhydride as a catalyst: : + → + This route suffers from the production of dichloroacetic acid and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Thiocyanate
Ammonium thiocyanate is an inorganic compound with the formula NH4SCN. It is the salt of the ammonium cation and the thiocyanate anion. Uses Ammonium thiocyanate is used in the manufacture of herbicides, thiourea, and transparent artificial resins; in matches; as a stabilizing agent in photography; in various rustproofing compositions; as an adjuvant in textile dyeing and printing; as a tracer in oil fields; in the separation of hafnium from zirconium (important for the production of hafnium-free zircalloy for use in nuclear fuel cladding), and in titrimetric analyses. In May 1945, USAAF General Victor E. Betrandias advanced a proposal to his superior General Arnold to use of ammonium thiocyanate to reduce rice crops in Japan as part of the bombing raids on their country. Ammonium thiocyanate can also be used to determine the iron content in soft drinks by colorimetry. Ammonium thiocyanate may also be used to separate quinidine, from liquors, after the isolation of quinine f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Berne
The University of Bern (german: Universität Bern, french: Université de Berne, la, Universitas Bernensis) is a university in the Swiss capital of Bern and was founded in 1834. It is regulated and financed by the Canton of Bern. It is a comprehensive university offering a broad choice of courses and programs in eight faculties and some 150 institutes. With around 18,576 students, the University of Bern is the third largest university in Switzerland. Organization The University of Bern operates at three levels: university, faculties and institutes. Other organizational units include interfaculty and general university units. The university's highest governing body is the Senate, which is responsible for issuing statutes, rules and regulations. Directly answerable to the Senate is the University Board of Directors, the governing body for university management and coordination. The board comprises the rector, the vice-rectors and the administrative director. The structures ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atom
Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across. They are so small that accurately predicting their behavior using classical physics, as if they were tennis balls for example, is not possible due to quantum effects. More than 99.94% of an atom's mass is in the nucleus. The protons have a positive electric charge, the electrons have a negative electric charge, and the neutrons have no electric charge. If the number of protons and electrons are equal, then the atom is electrically neutral. If an atom has more or fewer electrons than protons, then it has an overall negative or positive charge, respectively – such atoms are called ions. The electrons of an atom are a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with other atoms when it forms chemical compounds or molecules. Description The combining capacity, or affinity of an ...—its atom making four electrons available to form covalent bond, covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust. Three Isotopes of carbon, isotopes occur naturally, Carbon-12, C and Carbon-13, C being stable, while Carbon-14, C is a radionuclide, decaying with a half-life of about 5,730 years. Carbon is one of the Timeline of chemical element discoveries#Ancient discoveries, few elements known since antiquity. Carbon is the 15th Abundance of elements in Earth's crust, most abundant element in the Earth's crust, and the Abundance of the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condensation Reaction
In organic chemistry, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. If water is lost, the reaction is also known as a dehydration synthesis. However other molecules can also be lost, such as ammonia, ethanol, acetic acid and hydrogen sulfide. The addition of the two molecules typically proceeds in a step-wise fashion to the addition product, usually in equilibrium, and with loss of a water molecule (hence the name condensation). The reaction may otherwise involve the functional groups of the molecule, and is a versatile class of reactions that can occur in acidic or basic conditions or in the presence of a catalyst. This class of reactions is a vital part of life as it is essential to the formation of peptide bonds between amino acids and to the biosynthesis of fatty acids. Many variations of condensation reactions exist. Common examples include the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
