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Sodium Bisulphite
Sodium bisulfite (or sodium bisulphite, sodium hydrogen sulfite) is a chemical mixture with the approximate chemical formula NaHSO3. Sodium bisulfite is not a real compound, but a mixture of salts that dissolve in water to give solutions composed of sodium and bisulfite ions. It appears in form of white or yellowish-white crystals with an odor of sulfur dioxide. Sodium bisulfite is used in a variety industries such as a food additive with E number E222 in the food industry. It is a reducing agent in the cosmetic and in the bleaching applications. Synthesis Sodium bisulfite solutions can be prepared by treating a solution of suitable base, such as sodium hydroxide or sodium bicarbonate with sulfur dioxide. :SO2 + NaOH → NaHSO3 :SO2 + NaHCO3 → NaHSO3 + CO2 Attempts to crystallize the product yield sodium metabisulfite (also called sodium disulfite), Na2S2O5. Upon dissolution of the metabisulfite in water, bisulfite is regenerated: :Na2S2O5 + H2O → 2 Na+ + 2 HS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Sulfite
Sodium sulfite (sodium sulphite) is the inorganic compound with the chemical formula Na2SO3. A white, water-soluble solid, it is used commercially as an antioxidant and preservative. It is also suitable for the softening of lignin in the pulping and refining processes of wood and Lignocellulosic biomass, lignocellulosic materials. A heptahydrate is also known but it is less useful because of its greater susceptibility toward oxidation by air. Preparation image:Sodium-sulfite-xtal-3x3x3-c-3D-bs-17.png, Structure of anhydrous sodium sulfite, left, thumb Sodium sulfite can be prepared by treating a solution of sodium hydroxide with sulfur dioxide. When conducted in warm water, Na2SO3 initially precipitates as a white solid. With more SO2, the solid dissolves to give the Na2S2O5, disulfite, which crystallizes upon cooling. : Sodium sulfite is made industrially by treating sulfur dioxide with a solution of sodium carbonate. The overall reaction is: : Uses Sodium sulfite is primaril ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Syntheses
''Inorganic Syntheses'' is a book series which aims to publish "detailed and foolproof" procedures for the synthesis of inorganic compounds. Although this series of books are edited, they usually are referenced like a journal, without mentioning the names of the checkers (referees) or the editor. A similar format is usually followed for the series '' Organic Syntheses''. Volumes See also * Organic SynthesesReferences {{chem-book-stub Book series introduced in 1939 ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sister Chromatids
A sister chromatid refers to the identical copies ( chromatids) formed by the DNA replication of a chromosome, with both copies joined together by a common centromere. In other words, a sister chromatid may also be said to be 'one-half' of the duplicated chromosome. A pair of sister chromatids is called a dyad. A full set of sister chromatids is created during the synthesis ( S) phase of interphase, when all the chromosomes in a cell are replicated. The two sister chromatids are separated from each other into two different cells during mitosis or during the second division of meiosis. Compare sister chromatids to homologous chromosomes, which are the two ''different'' copies of a chromosome that diploid organisms (like humans) inherit, one from each parent. Sister chromatids are by and large identical (since they carry the same alleles, also called variants or versions, of genes) because they derive from one original chromosome. An exception is towards the end of meiosis, after ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transamination
Transamination is a chemical reaction that transfers an amino group to a ketoacid to form new amino acids.This pathway is responsible for the deamination of most amino acids. This is one of the major degradation pathways which convert essential amino acids to non-essential amino acids (amino acids that can be synthesized de novo by the organism). Transamination in biochemistry is accomplished by enzymes called transaminases or aminotransferases. α-ketoglutarate acts as the predominant amino-group acceptor and produces glutamate as the new amino acid. :Amino acid, Aminoacid + α-ketoglutarate ↔ α-keto acid + Glutamic acid, glutamate Glutamate's amino group, in turn, is transferred to oxaloacetate in a second transamination reaction yielding aspartate. :Glutamic acid, Glutamate + oxaloacetate ↔ α-ketoglutarate + aspartate Mechanism of action Transamination catalyzed by aminotransferase occurs in two stages. In the first step, the α amino group of an amino acid is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcinogen
A carcinogen () is any agent that promotes the development of cancer. Carcinogens can include synthetic chemicals, naturally occurring substances, physical agents such as ionizing and non-ionizing radiation, and biologic agents such as viruses and bacteria. Most carcinogens act by creating mutations in DNA that disrupt a cell's normal processes for regulating growth, leading to uncontrolled cellular proliferation. This occurs when the cell's DNA repair processes fail to identify DNA damage allowing the defect to be passed down to daughter cells. The damage accumulates over time. This is typically a multi-step process during which the regulatory mechanisms within the cell are gradually dismantled allowing for unchecked cellular division. The specific mechanisms for carcinogenic activity is unique to each agent and cell type. Carcinogens can be broadly categorized, however, as activation-dependent and activation-independent which relate to the agent's ability to engage dir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Agency For Research On Cancer
The International Agency for Research on Cancer (IARC; ) is an intergovernmental agency forming part of the World Health Organization of the United Nations. Its role is to conduct and coordinate research into the causes of cancer. It also cancer registry, collects and publishes disease surveillance, surveillance data regarding the occurrence of cancer worldwide. Its IARC monographs programme identifies carcinogenic hazards and evaluates environmental carcinogen, causes of cancer in humans. IARC has its own governing council, and in 1965 the first members were West Germany, France, Italy, the United Kingdom, and the United States of America. Today, IARC's membership has grown to 29 countries. History In late February 1963, after he experienced his spouse suffering and dying of cancer, journalist and Mouvement de la Paix, peace activist Yves Poggioli sent a letter to Emmanuel d'Astier de La Vigerie, Emmanuel d'Astier de la Vignerie relating his story, and urging support for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antichlor
An antichlor is a substance used to decompose residual hypochlorite or chlorine after chlorine-based bleaching, in order to prevent ongoing reactions with, and therefore damage to, the material that has been bleached. Antichlors include sodium bisulfite, potassium bisulfite, sodium metabisulfite, sodium thiosulfate, and hydrogen peroxide. USP Technologies In the textile industry, the antichlor is usually added right before the end of the ing process. Antichlors are used mainly on , |
Flow Injection Analysis
Flow injection analysis (FIA) is an approach to chemical analysis. It is accomplished by injecting a plug of sample into a flowing carrier stream. The principle is similar to that of Segmented Flow Analysis (SFA) but no air is injected into the sample or reagent streams.. Overview FIA is an automated method of chemical analysis in which a sample is injected into a flowing carrier solution that mixes with reagents before reaching a detector. Over past 30 years, FIA techniques developed into a wide array of applications using spectrophotometry, fluorescence spectroscopy, atomic absorption spectroscopy, mass spectrometry, and other methods of instrumental analysis for detection. Automated sample processing, high repeatability, adaptability to micro-miniaturization, containment of chemicals, waste reduction, and reagent economy in a system that operates at microliter levels are all valuable assets that contribute to the application of flow injection to real-world assays. The main ass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-performance Liquid Chromatography
High-performance liquid chromatography (HPLC), formerly referred to as high-pressure liquid chromatography, is a technique in analytical chemistry used to separate, identify, and quantify specific components in mixtures. The mixtures can originate from food, chemicals, pharmaceuticals, biological, environmental and agriculture, etc., which have been dissolved into liquid solutions. It relies on high pressure pumps, which deliver mixtures of various solvents, called the mobile phase, which flows through the system, collecting the sample mixture on the way, delivering it into a cylinder, called the column, filled with solid particles, made of adsorbent material, called the stationary phase. Each component in the sample interacts differently with the adsorbent material, causing different migration rates for each component. These different rates lead to separation as the species flow out of the column into a specific detector such as UV detectors. The output of the detecto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of AOAC International
The ''Journal of AOAC International'' is a peer-reviewed scientific journal publishing research articles in the field of analytical chemistry and microbiology covering basic and applied research in analytical sciences related to foods, drugs, agriculture, the environment, and more. It is published by Oxford University Press on behalf of AOAC International and the editor-in-chief is David B. Schmidt. The journal was established in 1915 as the ''Journal of Association of Official Agricultural Chemists'', obtaining its current name in 1992. Abstracting and indexing According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 1.913. References External links * {{Official website, https://www.aoac.org/journa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxford University Press
Oxford University Press (OUP) is the publishing house of the University of Oxford. It is the largest university press in the world. Its first book was printed in Oxford in 1478, with the Press officially granted the legal right to print books by decree in 1586. It is the second-oldest university press after Cambridge University Press, which was founded in 1534. It is a department of the University of Oxford. It is governed by a group of 15 academics, the Delegates of the Press, appointed by the Vice Chancellor, vice-chancellor of the University of Oxford. The Delegates of the Press are led by the Secretary to the Delegates, who serves as OUP's chief executive and as its major representative on other university bodies. Oxford University Press has had a similar governance structure since the 17th century. The press is located on Walton Street, Oxford, Walton Street, Oxford, opposite Somerville College, Oxford, Somerville College, in the inner suburb of Jericho, Oxford, Jericho. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Conference Of Governmental Industrial Hygienists
The American Conference of Governmental Industrial Hygienists (ACGIH) is a professional association of industrial hygienists and practitioners of related professions, with headquarters in Cincinnati, Ohio. One of its goals is to advance worker protection by providing timely, objective, scientific information to occupational and environmental health professionals. History The National Conference of Governmental Industrial Hygienists (NCGIH) convened on June 27, 1938, in Washington, D.C. NCGIH's original constitution limited full membership to two representatives from each governmental industrial hygiene agency. Associate membership was made available to other professional personnel of the agencies holding full memberships, and also to personnel of educational institutions engaged in teaching industrial hygiene. Governmental industrial hygiene personnel of other countries were eligible for affiliated membership. The Conference came into being with 59 members, one affiliated me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
