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Thiodiglycol
Thiodiglycol, or bis(2-hydroxyethyl)sulfide (also known as 2,2-thiodiethanol or TDE), is the organosulfur compound with the formula S(CH2CH2OH)2. It is miscible with water and polar organic solvents. It is a colorless liquid. It is structurally similar to diethylene glycol. Thiodiglycol is manufactured by reaction of 2-chloroethanol with sodium sulfide. Thiodiglycol has both polar and nonpolar solvent properties. It is used as a solvent in a variety of applications ranging from dyeing textiles to inks in some ballpoint pens. In chemical synthesis, it is used as a building block for protection products, dispersants, fibers, plasticizers, rubber accelerators, pesticides, dyes, and various other organic chemicals. In the manufacture of polymers, it is used as a chain transfer agent. As an antioxidant, it is used as an additive in lubricants. Thiodiglycol is used as a mounting medium in microscopy. The ability to vary the refractive index of the medium by varying the concentrat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mustard Gas
Mustard gas or sulfur mustard is a chemical compound belonging to a family of cytotoxic and blister agents known as mustard agents. The name ''mustard gas'' is technically incorrect: the substance, when dispersed, is often not actually a gas, but is instead in the form of a fine mist of liquid droplets.https://www.acs.org/content/dam/acsorg/education/resources/highschool/chemmatters/gc-mustard-gas-personal-safety-and-natl-security.pdf Mustard gases form blisters on exposed skin and in the lungs, often resulting in prolonged illness ending in death. The active ingredient in typical mustard gas is the organosulfur compound bis(2-chloroethyl) sulfide. In the wider sense, compounds with the structural element are known as ''sulfur mustards'' and ''nitrogen mustards'', respectively. Such compounds are potent alkylating agents, which can interfere with several biological processes. History as chemical weapons As a chemical weapon, mustard gas was first used in World War I, and has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-Chloroethanol
2-Chloroethanol (also called ethylene chlorohydrin or glycol chlorohydrin) is an organic chemical compound with the chemical formula HOCH2CH2Cl and the ''simplest'' beta-halohydrin (chlorohydrin). This colorless liquid has a pleasant ether-like odor. It is miscible with water. The molecule is bifunctional, consisting of both an alkyl chloride and an alcohol functional group. Synthesis and applications 2-Chloroethanol is produced by treating ethylene with hypochlorous acid: : 2-Chloroethanol was once produced on a large scale as a precursor to ethylene oxide: : :HOCH2CH2Cl + NaOH → C2H4O + NaCl + H2O This application has been supplanted by the more economic direct oxidation of ethylene. Otherwise chloroethanol is still used in the production of pharmaceuticals, biocides, and plasticizers. Many of these applications entail its use in installing 2-hydroxyethyl groups. Several dyes are prepared by the alkylation of aniline derivatives with chloroethanol. It is also used for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bis(2-chloroethyl)sulfide
Bis(2-chloroethyl)sulfide is the organosulfur compound with the formula . It is a prominent member of a family of cytotoxic and blister agents known as mustard agents. Sometimes referred to as ''mustard gas'', the term is technically incorrect: bis(2-chloroethyl)sulfide is a liquid at room temperature. In warfare it was dispersed in the form of a fine mist of liquid droplets.https://www.acs.org/content/dam/acsorg/education/resources/highschool/chemmatters/gc-mustard-gas-personal-safety-and-natl-security.pdf Synthesis Bis(2-chloroethyl)sulfide has been prepared in a variety of variety of ways. In the Depretz method, sulfur dichloride is treated with ethylene: : In the Levinstein process, disulfur dichloride is used instead: : + S8 In the Meyer method, thiodiglycol is produced from chloroethanol and potassium sulfide, and the resulting diol is then treated with phosphorus trichloride: : In the Meyer–Clarke method, concentrated hydrochloric acid (HCl) is used instead of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Schedule 2 Substances (CWC)
Schedule 2 substances, in the sense of the Chemical Weapons Convention, are chemicals that can either be used as chemical weapons themselves or used in the manufacture of chemical weapons but that have small-scale applications outside of chemical warfare and so can be legitimately manufactured in small quantities. An example is thiodiglycol, which can be used in the manufacture of mustard agents but is also used as a solvent in inks. Manufacture must be declared as their production is subject to declaration to the Organisation for the Prohibition of Chemical Weapons (OPCW) per Part VII of the "Verification Annex", and they may not be exported to countries that are not party to the Convention. As with the other schedules, they are sub-divided into Part A substances, which are chemicals that can be used directly as weapons, and Part B, which are precursors useful in the manufacture of chemical weapons. The Schedule 2 list is one of three lists. Chemicals that can be used as weapon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Weapons Convention
The Chemical Weapons Convention (CWC), officially the Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on their Destruction, is an arms control treaty administered by the Organisation for the Prohibition of Chemical Weapons (OPCW), an intergovernmental organization based in The Hague, The Netherlands. The treaty entered into force on 29 April 1997, and prohibits the large-scale use, development, production, stockpiling and transfer of chemical weapons and their precursors, except for very limited purposes (research, medical, pharmaceutical or protective). The main obligation of member states under the convention is to effect this prohibition, as well as the destruction of all current chemical weapons. All destruction activities must take place under OPCW verification. As of August 2022, 193 states have become parties to the CWC and accept its obligations. Israel has signed but not ratified the agreement, while three other U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MmHg
A millimetre of mercury is a manometric unit of pressure, formerly defined as the extra pressure generated by a column of mercury one millimetre high, and currently defined as exactly pascals. It is denoted mmHg or mm Hg. Although not an SI unit, the millimetre of mercury is still routinely used in medicine, meteorology, aviation, and many other scientific fields. One millimetre of mercury is approximately 1 Torr, which is of standard atmospheric pressure ( ≈ ). Although the two units are not equal, the relative difference (less than ) is negligible for most practical uses. History For much of human history, the pressure of gases like air was ignored, denied, or taken for granted, but as early as the 6th century BC, Greek philosopher Anaximenes of Miletus claimed that all things are made of air that is simply changed by varying levels of pressure. He could observe water evaporating, changing to a gas, and felt that this applied even to solid matter. More cond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chain Transfer Agent
Chain transfer is a polymerization reaction by which the activity of a growing polymer chain is transferred to another molecule. :P• + XR' → PX + R'• Chain transfer reactions reduce the average molecular weight of the final polymer. Chain transfer can be either introduced deliberately into a polymerization (by use of a ''chain transfer agent'') or it may be an unavoidable side-reaction with various components of the polymerization. Chain transfer reactions occur in most forms of addition polymerization including radical polymerization, ring-opening polymerization, coordination polymerization, and cationic polymerization, as well as anionic polymerization. Types Chain transfer reactions are usually categorized by the nature of the molecule that reacts with the growing chain. * Transfer to chain transfer agent. Chain transfer agents have at least one weak chemical bond, which therefore facilitates the chain transfer reaction. Common chain transfer agents include thiols, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solvents
A solvent (s) (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for polar molecules and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell. The quantity of solute that can dissolve in a specific volume of solvent varies with temperature. Major uses of solvents are in paints, paint removers, inks, and dry cleaning. Specific uses for organic solvents are in dry cleaning (e.g. tetrachloroethylene); as paint thinners (toluene, turpentine); as nail polish removers and solvents of glue (acetone, methyl acetate, ethyl acetate); in spot removers (hexane, petrol ether); in detergents ( citrus terpenes); and in perfumes (ethanol). Solvents find various applications in chemical, pharmaceutical, oil, and gas industries, including in chemical synt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urine
Urine is a liquid by-product of metabolism in humans and in many other animals. Urine flows from the kidneys through the ureters to the urinary bladder. Urination results in urine being excretion, excreted from the body through the urethra. Cell (biology), Cellular metabolism generates many by-products that are rich in nitrogen and must be clearance (medicine), cleared from the Circulatory system, bloodstream, such as urea, uric acid, and creatinine. These by-products are expelled from the body during urination, which is the primary method for excreting water-soluble chemicals from the body. A urinalysis can detect nitrogenous wastes of the mammalian body. Urine plays an important role in the earth's nitrogen cycle. In balanced ecosystems, urine fertilizes the soil and thus helps plants to grow. Therefore, Reuse of excreta, urine can be used as a fertilizer. Some animals use it to territory (animal)#Scent marking, mark their territories. Historically, aged or fermented urine (kn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis is the cleavage of biomolecules where a water molecule is consumed to effect the separation of a larger molecule into component parts. When a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g., sucrose being broken down into glucose and fructose), this is recognized as saccharification. Hydrolysis reactions can be the reverse of a condensation reaction in which two molecules join into a larger one and eject a water molecule. Thus hydrolysis adds water to break down, whereas condensation builds up by removing water. Types Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both the substance and w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refractive Index
In optics, the refractive index (or refraction index) of an optical medium is a dimensionless number that gives the indication of the light bending ability of that medium. The refractive index determines how much the path of light is bent, or refracted, when entering a material. This is described by Snell's law of refraction, , where ''θ''1 and ''θ''2 are the angle of incidence and angle of refraction, respectively, of a ray crossing the interface between two media with refractive indices ''n''1 and ''n''2. The refractive indices also determine the amount of light that is reflected when reaching the interface, as well as the critical angle for total internal reflection, their intensity ( Fresnel's equations) and Brewster's angle. The refractive index can be seen as the factor by which the speed and the wavelength of the radiation are reduced with respect to their vacuum values: the speed of light in a medium is , and similarly the wavelength in that medium is , where '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microscopy
Microscopy is the technical field of using microscopes to view objects and areas of objects that cannot be seen with the naked eye (objects that are not within the resolution range of the normal eye). There are three well-known branches of microscopy: optical, electron, and scanning probe microscopy, along with the emerging field of X-ray microscopy. Optical microscopy and electron microscopy involve the diffraction, reflection, or refraction of electromagnetic radiation/electron beams interacting with the specimen, and the collection of the scattered radiation or another signal in order to create an image. This process may be carried out by wide-field irradiation of the sample (for example standard light microscopy and transmission electron microscopy) or by scanning a fine beam over the sample (for example confocal laser scanning microscopy and scanning electron microscopy). Scanning probe microscopy involves the interaction of a scanning probe with the surface of the objec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
