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Sodium Dimethyldithiocarbamate
Sodium dimethyldithiocarbamate is the organosulfur compound with the formula . It is one of the simplest organic dithiocarbamates. It is a white or pale yellow, water soluble solid. The compound is a precursor to fungicides and rubber chemicals. Preparation Sodium dimethyldithiocarbamate typically crystallizes from water as the dihydrate NaS2CN(CH3)2.2H2O. The anhydrous salt and the trihydrate are often used interchangeably. Sodium dimethyldithiocarbamate is obtained by treating carbon disulfide with dimethylamine in the presence of sodium hydroxide: :CS2 + HN(CH3)2 + NaOH → NaS2CN(CH3)2 + H2O Other dithiocarbamates can be prepared similarly from secondary amines and carbon disulfide. They are used as chelating agents for transition metal ions and as precursors to herbicides and vulcanization reagents. Uses left, 222px, Iron tris(dimethyldithiocarbamate) (Fe(S2CNMe2)3) is illustrative of hundreds of known dithiocarbamate complexes. It is a component of various pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organosulfur Compound
Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur derivatives, e.g., saccharin. Nature is abound with organosulfur compounds—sulfur is vital for life. Of the 20 common amino acids, two ( cysteine and methionine) are organosulfur compounds, and the antibiotics penicillin and sulfa drugs both contain sulfur. While sulfur-containing antibiotics save many lives, sulfur mustard is a deadly chemical warfare agent. Fossil fuels, coal, petroleum, and natural gas, which are derived from ancient organisms, necessarily contain organosulfur compounds, the removal of which is a major focus of oil refineries. Sulfur shares the chalcogen group with oxygen, selenium, and tellurium, and it is expected that organosulfur compounds have similarities with carbon–oxygen, carbon–selenium, and car ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pesticide
Pesticides are substances that are used to control pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for approximately 50% of all pesticide use globally. Most pesticides are used as plant protection products (also known as crop protection products), which in general protect plants from weeds, fungi, or insects. In general, a pesticide is a chemical or biological agent (such as a virus, bacterium, or fungus) that deters, incapacitates, kills, or otherwise discourages pests. Target pests can include insects, plant pathogens, weeds, molluscs, birds, mammals, fish, nematodes (roundworms), and microbes that destroy property, cause nuisance, spread disease, or are disease vectors. Along with these benefits, pesticides also have drawbacks, such as potential toxicity to humans and other species. Definition The word pesticide derives from the Latin ''pestis'' (plagu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Environmental Protection Agency
The Environmental Protection Agency (EPA) is an independent agency of the United States government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it began operation on December 2, 1970, after Nixon signed an executive order. The order establishing the EPA was ratified by committee hearings in the House and Senate. The agency is led by its administrator, who is appointed by the president and approved by the Senate. The current administrator is Lee Zeldin. The EPA is not a Cabinet department, but the administrator is normally given cabinet rank. The EPA has its headquarters in Washington, D.C. There are regional offices for each of the agency's ten regions, as well as 27 laboratories around the country. The agency conducts environmental assessment, research, and education. It has the responsibility of maintaining and enforcing national standards under a variety of environmental laws, in consultat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiram
Thiram is the simplest thiuram disulfide and the oxidized dimer of dimethyldithiocarbamate. It is used as a fungicide, ectoparasiticide to prevent fungal diseases in seed and crops and similarly as an animal repellent to protect fruit trees and ornamentals from damage by rabbits, rodents and deer. It is effective against Stem gall of coriander, damping off, smut of millet, neck rot of onion, etc. Thiram has been used in the treatment of human scabies, as a sun screen and as a bactericide applied directly to the skin or incorporated into soap. Thiram is also used as a sulfur source and secondary accelerator the sulfur vulcanization Sulfur vulcanization is a chemical process for converting natural rubber or related polymers into materials of varying hardness, elasticity, and mechanical durability by heating them with sulfur or sulfur-containing compounds. Sulfur forms cros ... of rubbers. Usage Thiram was traditionally used in apple and wine farming. Since 2010 most thira ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel Bis(dimethyldithiocarbamate)
Nickel bis(dimethyldithiocarbamate) is the coordination complex on nickel and dimethyldithiocarbamate, with the formula Ni(S2CNMe2)2 (Me = methyl). It is the prototype for a large number of square planar bis(dialkhyldithiocarbamate)s of nickel(II), which feature diverse organic substituents. Nickel bis(dimethyldithiocarbamate) has been marketed as a fungicide, and related complexes are used as stabilizers in polymers. Preparation and structure The compound precipitates as a light green solid upon combining aqueous solutions of nickel(II) salts and sodium dimethyldithiocarbamate. In terms of structure and bonding, the nickel is square planar, and the complex is diamagnetic. The structure of the closely related nickel bis(diethyldithiocarbamate) has been determined by X-ray crystallography. Oxidation of nickel bis(dieethyldithiocarbamate) gives the red-brown nickel(IV) complex .{{cite journal , last1=Mazumder , first1=Md. Motiur R. , last2=Dalpati , first2=Niharika , last3=Pokk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferric Dimethyldithiocarbamate
Iron tris(dimethyldithiocarbamate) is the coordination complex of iron with dimethyldithiocarbamate with the formula Fe(S2CNMe2)3 (Me = methyl). It is marketed as a fungicide. Synthesis, structure, bonding Iron tris(dithiocarbamate)s are typically are prepared by salt metathesis reactions. Iron tris(dimethyldithiocarbamate) is an octahedral coordination complex of iron(III) with D3 symmetry group, symmetry. Spin crossover (SCO) was first observed in 1931 by Cambi ''et al.'' who discovered anomalous magnetic behavior for the tris(N,N-dialkyldithiocarbamatoiron(III) complexes. The spin states of these complexes are sensitive to the nature of the amine substituents. Reactions Iron tris(dithiocarbamate)s react with nitric oxide to give a nitrosyl complex: : This efficient chemical trapping reaction provides a means to detect NO. Reflecting the strongly donating properties of dithiocarbamate ligands, iron tris(dithiocarbamate)s oxidize at relatively mild potentials to give isolabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Dimethyldithiocarbamate
Zinc dimethyldithiocarbamate is a coordination complex of zinc with dimethyldithiocarbamate. It is a pale yellow solid that is used as a fungicide, the sulfur vulcanization of rubber, and other industrial applications. Applications Known as ziram in agriculture, it was introduced in the United States in 1960 as a broad-spectrum fungicide. It was used to address scab on apples and pears, leaf curl in peaches, and anthracnose and blight in tomatoes. In 1981, additional uses for ziram were approved, including the prevention of leaf blight and scab on almonds, shot-hole in apricots, brown rot and leaf spot in cherries, and scab and anthracnose in pecans. Ziram also began to be used on residential ornaments as a bird and mammal repellent. As a protectant fungicide, it is active on the plant’s surface where it forms a chemical barrier between the plant and a fungus. A protectant fungicide is not absorbed into the plant and must be applied prior to infection. Ziram can either be direct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt (chemistry)
In chemistry, a salt or ionic compound is a chemical compound consisting of an assembly of positively charged ions ( cations) and negatively charged ions ( anions), which results in a compound with no net electric charge (electrically neutral). The constituent ions are held together by electrostatic forces termed ionic bonds. The component ions in a salt can be either inorganic, such as chloride (Cl−), or organic, such as acetate (). Each ion can be either monatomic, such as sodium (Na+) and chloride (Cl−) in sodium chloride, or polyatomic, such as ammonium () and carbonate () ions in ammonium carbonate. Salts containing basic ions hydroxide (OH−) or oxide (O2−) are classified as bases, such as sodium hydroxide and potassium oxide. Individual ions within a salt usually have multiple near neighbours, so they are not considered to be part of molecules, but instead part of a continuous three-dimensional network. Salts usually form crystalline structures ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dithiocarbamate
In organic chemistry, a dithiocarbamate is a chemical compound with the general formula . It contains the functional group with the Chemical structure, structure . It is the analog of a carbamate in which both oxygen atoms are replaced by sulfur atoms (when only one oxygen is replaced the result is thiocarbamate). Dithiocarbamate also refers to the dithiocarbamate ion and its salts. A common example is sodium diethyldithiocarbamate . Dithiocarbamates and their derivatives are widely used in the vulcanization of rubber. Formation Many secondary amines react with carbon disulfide and sodium hydroxide to form dithiocarbamate salts: : Ammonia reacts with carbon disulfide, similarly, to give ammonium dithiocarbamate: : Dithiocarbamate salts are pale colored solids that are soluble in water and Solvent, polar organic solvents. Dithiocarbamic acid A primary amine and carbon disulfide react to give a dithiocarbamic acid: : In the presence of diimides or pyridine, these acids convert t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vulcanization
Vulcanization (British English: vulcanisation) is a range of processes for hardening rubbers. The term originally referred exclusively to the treatment of natural rubber with sulfur, which remains the most common practice. It has also grown to include the hardening of other (synthetic) rubbers via various means. Examples include silicone rubber via room temperature vulcanizing and chloroprene rubber (neoprene) using metal oxides. Vulcanization can be defined as the curing of elastomers, with the terms 'vulcanization' and 'curing' sometimes used interchangeably in this context. It works by forming cross-links between sections of the polymer chain which results in increased rigidity and durability, as well as other changes in the mechanical and electrical properties of the material. Vulcanization, in common with the curing of other thermosetting polymers, is generally irreversible. The word was suggested by William Brockedon (a friend of Thomas Hancock who attained the B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herbicide
Herbicides (, ), also commonly known as weed killers, are substances used to control undesired plants, also known as weeds.EPA. February 201Pesticides Industry. Sales and Usage 2006 and 2007: Market Estimates. Summary in press releasMain page for EPA reports on pesticide use ihere Selective herbicides control specific weed species while leaving the desired crop relatively unharmed, while non-selective herbicides (sometimes called "total weed killers") kill plants indiscriminately. The combined effects of herbicides, nitrogen fertilizer, and improved cultivars has increased yields (per acre) of major crops by three to six times from 1900 to 2000. In the United States in 2012, about 91% of all herbicide usage, was determined by weight applied, in agriculture. In 2012, world pesticide expenditures totaled nearly US$24.7 billion; herbicides were about 44% of those sales and constituted the biggest portion, followed by insecticides, fungicides, and fumigants. Herbicide is also used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
