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Tefluthrin
Tefluthrin is the ISO common name for an organic compound that is used as a pesticide. It is a pyrethroid, a class of synthetic insecticides that mimic the structure and properties of the naturally occurring insecticide pyrethrin which is present in the flowers of ''Chrysanthemum cinerariifolium''. Pyrethroids such as tefluthrin are often preferred as active ingredients in agricultural insecticides because they are more cost-effective and longer acting than natural pyrethrins. It is effective against soil pests because it can move as a vapour without irreversibly binding to soil particles: in this respect it differs from most other pyrethroids. Synthesis : Tefluthrin (X=CH3) is manufactured by the esterification of cyhalothrin acid chloride with 4-methyl-2,3,5,6-tetrafluorobenzyl alcohol. The latter was a novel compound when tefluthrin was invented and the choice of routes to it has been discussed. History By 1974, a team of Rothamsted Research scientists had discovered three p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Cyhalothrin
Cyhalothrin (ISO common name) is an organic compound that, in specific isomeric forms, is used as a pesticide. It is a pyrethroid, a class of synthetic insecticides that mimic the structure and properties of the naturally occurring insecticide pyrethrin which is present in the flowers of ''Chrysanthemum cinerariifolium''. Pyrethroids, such as cyhalothrin, are often preferred as an active ingredient in agricultural insecticides because they are more cost-effective and longer acting than natural pyrethrins. λ-and γ-cyhalothrin are now used to control insects and spider mites in crops including cotton, cereals, potatoes and vegetables. Structure and stereochemistry : Gamma-cyhalothrin and lambda-cyhalothrin are the active ingredients in the current commercial products based on cyhalothrin. Both are cyanohydrin esters of cis-3- Z)-2-chloro-3,3,3-trifluoropropenyl2,2-dimethylcyclopropanecarboxylic acid. All of the insecticidal activity is due to the proportion of absolute stereoch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Racemic Mixture
In chemistry, a racemic mixture or racemate () is a mixture that has equal amounts (50:50) of left- and right-handed enantiomers of a chiral molecule or salt. Racemic mixtures are rare in nature, but many compounds are produced industrially as racemates. History The first known racemic mixture was racemic acid, which Louis Pasteur found to be a mixture of the two enantiomeric isomers of tartaric acid. He manually separated the crystals of a mixture, starting from an aqueous solution of the sodium ammonium salt of racemate tartaric acid. Pasteur benefited from the fact that ammonium tartrate salt gives enantiomeric crystals with distinct crystal forms (at 77 °F). Reasoning from the macroscopic scale down to the molecular, he reckoned that the molecules had to have non-superimposable mirror images. A sample with only a single enantiomer is an ''enantiomerically pure'' or ''enantiopure'' compound. Etymology The word ''racemic'' derives from Latin , meaning pertaining to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
License
A license (American English) or licence (Commonwealth English) is an official permission or permit to do, use, or own something (as well as the document of that permission or permit). A license is granted by a party (licensor) to another party (licensee) as an element of an agreement between those parties. In the case of a license issued by a government, the license is obtained by applying for it. In the case of a private party, it is by a specific agreement, usually in writing (such as a lease or other contract). The simplest definition is "A license is a promise not to sue", because a license usually either permits the licensed party to engage in an illegal activity, and subject to prosecution, without the license (e.g. Fishing license, fishing, Driver's license, driving an automobile, or operating a Broadcast license, broadcast radio or television station), or it permits the licensed party to do something that would violate the rights of the licensing party (e.g. make copie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Diabrotica Balteata
''Diabrotica balteata'' is a species of cucumber beetle in the family Chrysomelidae known commonly as the banded cucumber beetle. It occurs in the Americas, where its distribution extends from the United States to Colombia and Venezuela in South America.Banded Cucumber Beetle, ''Diabrotica balteata'' Leconte. Plant Health - Pest and Diseases Image Library (PaDIL). It is also present in .Datasheet: ''Diabrotica balteata''. 2017. Invasive Species Compendium. CABI. It is a [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Biological Activity
In pharmacology, biological activity or pharmacological activity describes the beneficial or adverse effects of a drug on living matter. When a drug is a complex chemical mixture, this activity is exerted by the substance's active ingredient or pharmacophore but can be modified by the other constituents. Among the various properties of chemical compounds, pharmacological/biological activity plays a crucial role since it suggests uses of the compounds in the medical applications. However, chemical compounds may show some adverse and toxic effects which may prevent their use in medical practice. Biological activity is usually measured by a bioassay and the activity is generally dosage-dependent, which is investigated via dose-response curves. Further, it is common to have effects ranging from beneficial to adverse for one substance when going from low to high doses. Activity depends critically on fulfillment of the ADME criteria. To be an effective drug, a compound not only ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Stereochemistry
Stereochemistry, a subdiscipline of chemistry, studies the spatial arrangement of atoms that form the structure of molecules and their manipulation. The study of stereochemistry focuses on the relationships between stereoisomers, which are defined as having the same molecular formula and sequence of bonded atoms (constitution) but differing in the geometric positioning of the atoms in space. For this reason, it is also known as Three-dimensional space, 3D chemistry—the prefix "stereo-" means "three-dimensionality". Stereochemistry applies to all kinds of compounds and ions, Organic chemistry, organic and Inorganic chemistry, inorganic species alike. Stereochemistry affects Biochemistry, biological, Physical chemistry, physical, and supramolecular chemistry. Stereochemistry reactivity (chemistry), reactivity of the molecules in question (dynamic stereochemistry). History In 1815, Jean-Baptiste Biot's observation of optical activity marked the beginning of organic stereochemistr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
E–Z Notation
''E''–''Z'' configuration, or the ''E''–''Z'' convention, is the IUPAC preferred method of describing the absolute stereochemistry of double bonds in organic chemistry. It is an extension of ''cis''–''trans'' isomer notation (which only describes ''relative stereochemistry'') that can be used to describe double bonds having two, three or four substituents. E and Z notation are only used when a compound doesn't have two identical substituents. Following the Cahn–Ingold–Prelog priority rules (CIP rules), each substituent on a double bond is assigned a priority, then positions of the higher of the two substituents on each carbon are compared to each other. If the two groups of higher priority are on opposite sides of the double bond (''trans'' to each other), the bond is assigned the configuration ''E'' (from ''entgegen'', , the German word for "opposite"). If the two groups of higher priority are on the same side of the double bond (''cis'' to each other), the bond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Trifluoromethyl
The trifluoromethyl group is a functional group that has the formula . The naming of is group is derived from the methyl group (which has the formula ), by replacing each hydrogen atom by a fluorine atom. Some common examples are trifluoromethane , 1,1,1-trifluoroethane , and hexafluoroacetone . Compounds with this group are a subclass of the organofluorines. Properties The trifluoromethyl group has a significant electronegativity that is often described as being intermediate between the electronegativities of fluorine and chlorine. For this reason, trifluoromethyl-substituted compounds are often strong acids, such as trifluoromethanesulfonic acid and trifluoroacetic acid. Conversely, the trifluoromethyl group lowers the basicity of compounds like trifluoroethanol. Uses The trifluoromethyl group occurs in certain pharmaceuticals, drugs, and abiotically synthesized natural fluorocarbon based compounds. The medicinal use of the trifloromethyl group dates from 1928, although re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Cost–benefit Analysis
Cost–benefit analysis (CBA), sometimes also called benefit–cost analysis, is a systematic approach to estimating the strengths and weaknesses of alternatives. It is used to determine options which provide the best approach to achieving benefits while preserving savings in, for example, transactions, activities, and functional business requirements. A CBA may be used to compare completed or potential courses of action, and to estimate or evaluate the value against the cost of a decision, project, or policy. It is commonly used to evaluate business or policy decisions (particularly public policy), commercial transactions, and project investments. For example, the U.S. Securities and Exchange Commission must conduct cost–benefit analyses before instituting regulations or deregulations. CBA has two main applications: # To determine if an investment (or decision) is sound, ascertaining if – and by how much – its benefits outweigh its costs. # To provide a basis for comparing in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Spectrum
A spectrum (: spectra or spectrums) is a set of related ideas, objects, or properties whose features overlap such that they blend to form a continuum. The word ''spectrum'' was first used scientifically in optics to describe the rainbow of colors in visible light after passing through a prism. In the optical spectrum, light wavelength is viewed as continuous, and spectral colors are seen to blend into one another smoothly when organized in order of their corresponding wavelengths. As scientific understanding of light advanced, the term came to apply to the entire electromagnetic spectrum, including radiation not visible to the human eye. ''Spectrum'' has since been applied by analogy to topics outside optics. Thus, one might talk about the " spectrum of political opinion", or the "spectrum of activity" of a drug, or the " autism spectrum". In these uses, values within a spectrum may not be associated with precisely quantifiable numbers or definitions. Such uses imply a bro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Patentable
Within the context of a national or multilateral body of law, an invention is patentable if it meets the relevant legal conditions to be granted a patent. By extension, patentability also refers to the substantive conditions that must be met for a patent to be held valid. Requirements The patent laws usually require that, for an invention to be patentable, it must be: * Patentable subject matter, i.e., a kind of subject-matter eligible for patent protection (also called "statutory patentable subject-matter") * Novel (i.e. at least some aspect of it must be new) * Non-obvious (in United States patent law) or involve an inventive step (in European patent law and under the Patent Cooperation Treaty) * Useful (in U.S. patent law) or be susceptible of industrial application (in European patent law) Usually the term "''patentability''" only refers to the four aforementioned "substantive" conditions, and does not refer to formal conditions such as the "sufficiency of disclosure" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
