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Sulfuryl Fluoride
Sulfuryl fluoride (also spelled ''sulphuryl fluoride'') is an inorganic compound with the formula SO2F2. It is an easily condensed gas and has properties more similar to sulfur hexafluoride than sulfuryl chloride, being resistant to hydrolysis even up to 150 °C. It is neurotoxic and a potent greenhouse gas, but is widely used as a fumigant insecticide to control termites. Structure, preparation, reactions The molecule is tetrahedral with C2v symmetry. The S-O distance is 140.5 pm, S-F is 153.0 pm. As predicted by VSEPR, the O-S-O angle is more open than the F-S-F angle, 124° and 97°, respectively. One synthesis begins with the preparation of potassium fluorosulfite: :SO2 + KF → KSO2F This salt is then chlorinated to give sulfuryl chloride fluoride: :KSO2F + Cl2 → SO2ClF + KCl Heating the sulfuryl chloride fluoride with potassium fluorosulfite at 180 °C gives the desired product: :SO2ClF + KSO2F → SO2F2 + KCl + SO2 Heating metal fluoros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenoyl Fluoride
Selenoyl fluoride, selenoyl difluoride, selenium oxyfluoride, or selenium dioxydifluoride is a chemical compound with the formula SeO2F2. Structure The shape of the molecule is a distorted tetrahedron with the O-Se-O angle being 126.2°, the O-Se-F angle being 108.0° and F-Se-F being 94.1°. The Se-F bond length is 1.685 Å and the selenium to oxygen bond is 1.575 Å long. Formation Selenoyl fluoride can be formed by the action of warm fluorosulfonic acid on barium selenate or selenic acid. SeO3 + SeF4 can give this gas along with other oxyfluorides. Reactions Selenoyl fluoride is more reactive than its analogon sulfuryl fluoride. It is easier to hydrolyse and to reduce. It may react violently upon contact with ammonia. Selenoyl fluoride reacting with xenon difluoride Xenon is a chemical element; it has symbol Xe and atomic number 54. It is a dense, colorless, odorless noble gas found in Earth's atmosphere in trace amounts. Although generally unreactive, it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfur Dioxide
Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is released naturally by volcanic activity and is produced as a by-product of metals refining and the burning of Sour gas, sulfur-Sour crude oil, bearing fossil fuels. Sulfur dioxide is somewhat toxic to humans, although only when inhaled in relatively large quantities for a period of several minutes or more. It was known to medieval alchemy, alchemists as "volatile spirit of sulfur". Structure and bonding SO2 is a bent molecule with ''C''2v Point groups in three dimensions, symmetry point group. A valence bond theory approach considering just ''s'' and ''p'' orbitals would describe the bonding in terms of resonance (chemistry), resonance between two resonance structures. The sulfur–oxygen bond has a bond order of 1.5. There is support f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bed Bug
Bed bugs are parasitic insects from the genus ''Cimex'', which are micropredators that haematophagy, feed on blood, usually at night. Their bites can result in a number of health impacts, including skin rashes, psychological effects, and allergy, allergic symptoms. Bed bug bites may lead to skin changes ranging from small areas of redness to prominent blisters. Symptoms may take between minutes to days to appear and Pruritus, itchiness is generally present. Some individuals may feel tired or have a fever. Typically, uncovered areas of the body are affected. Their bites are not known to transmit any infectious disease. Complications may rarely include necrotic, areas of dead skin or vasculitis. Bed bug bites are caused primarily by two species of insects: ''Cimex lectularius'' (the common bed bug) and ''Cimex hemipterus'', found primarily in the tropics. Their size ranges between 1 and 7 mm. They spread by crawling between nearby locations or by being carried within person ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bark Beetle
A bark beetle is the common name for the subfamily of beetles Scolytinae. Previously, this was considered a distinct family (Scolytidae), but is now understood to be a specialized clade of the "true weevil" family (Curculionidae). Although the term "bark beetle" refers to the fact that many species feed in the inner bark (phloem) layer of trees, the subfamily also has many species with other lifestyles, including some that bore into wood, feed in fruit and seeds, or tunnel into herbaceous plants. Well-known species are members of the type genus '' Scolytus'', namely the European elm bark beetle ''S. multistriatus'' and the large elm bark beetle ''S. scolytus'', which like the American elm bark beetle '' Hylurgopinus rufipes'', transmit Dutch elm disease fungi (''Ophiostoma''). The mountain pine beetle ''Dendroctonus ponderosae'', southern pine beetle '' Dendroctonus frontalis'', and their near relatives are major pests of conifer forests in North America. A similarly aggres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deathwatch Beetle
The deathwatch beetle (''Xestobium rufovillosum'') is a species of woodboring beetle that sometimes infests the structural timbers of old buildings. The adult beetle is brown and measures on average long. Eggs are laid in dark crevices in old wood inside buildings, trees, and inside tunnels left behind by previous larvae. The larvae bore into the timber, feeding for up to ten years before pupating, and later emerging from the wood as adult beetles. Timber that has been damp and is affected by fungal decay is soft enough for the larvae to chew through. They obtain nourishment by using enzymes present in their gut to digest the cellulose and hemicellulose in the wood. The larvae of deathwatch beetles weaken the structural timbers of a building by tunneling through them. Treatment with insecticides to kill the larvae is largely ineffective, and killing the adult beetles when they emerge in spring and early summer may be a better option. However, infestation by these beetles is oft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Powderpost Beetle
Powderpost beetles are a group of seventy species of woodboring beetles classified in the insect subfamily Lyctinae. These beetles, along with spider beetles, death watch beetles, common furniture beetles, skin beetles, and others, make up the superfamily Bostrichoidea. While most woodborers have a large prothorax, powderpost beetles do not, making their heads more visible. In addition to this, their antennae have two-jointed clubs. They are considered pests and attack deciduous trees, over time reducing the wood to a powdery dust. The damage caused by longhorn beetles (family Cerambycidae) is often confused with that of powderpost beetles, but the two groups are unrelated. The larvae of the Cerambycidae are white, straight and generally flat-headed, whereas those of the Bostrichidae are white and C-shaped. Name The term "powderpost" comes from the fact that the larvae of these beetles feed on wood and, given enough time, can reduce it to a mass of fine powder. Because of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodent
Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal species are rodents. They are native to all major land masses except for Antarctica, and several oceanic islands, though they have subsequently been introduced to most of these land masses by human activity. Rodents are extremely diverse in their ecology and lifestyles and can be found in almost every terrestrial habitat, including human-made environments. Species can be arboreal, fossorial (burrowing), saltatorial/ricochetal (leaping on their hind legs), or semiaquatic. However, all rodents share several morphological features, including having only a single upper and lower pair of ever-growing incisors. Well-known rodents include Mouse, mice, rats, squirrels, prairie dogs, porcupines, beavers, Cavia, guinea pigs, and hamsters. Once included wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insecticide Resistance Action Committee
The Insecticide Resistance Action Committee (IRAC) was formed in 1984 and works as a specialist technical group of the industry association CropLife to be able to provide a coordinated industry response to prevent or delay the development of insecticide resistance in insect, mite and nematode pests. IRAC strives to facilitate communication and education on insecticide and traits resistance as well as to promote the development and facilitate the implementation of insecticide resistance management strategies. IRAC is recognised by the Food and Agriculture Organization (FAO) and the World Health Organization (WHO) of the United Nations as an advisory body on matters pertaining to insecticide resistance. Pesticideresistance.org is a database financed by IRAC, US Department of Agriculture, and others. Sponsors IRAC's sponsors are: ADAMA, BASF, Bayer CropScience, Corteva, FMC, Mitsui Chemicals, Nihon Nohyaku, Sumitomo Chemical, Syngenta and UPL. Mode of action classification ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mode Of Action
In pharmacology and biochemistry, mode of action (MoA) describes a functional or anatomical change, resulting from the exposure of a living organism to a substance. In comparison, a mechanism of action (MOA) describes such changes at the molecular level. A mode of action is important in classifying chemicals, as it represents an intermediate level of complexity in between molecular mechanisms and physiological outcomes, especially when the exact molecular target has not yet been elucidated or is subject to debate. A mechanism of action of a chemical could be "binding to DNA" while its broader mode of action would be "transcriptional regulation". However, there is no clear consensus and the term mode of action is also often used, especially in the study of pesticides, to describe molecular mechanisms such as action on specific nuclear receptors or enzymes. Despite this, there are classification attempts, such as the HRAC's classification Classification is the activity of assign ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insecticide
Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. The major use of insecticides is in agriculture, but they are also used in home and garden settings, industrial buildings, for vector control, and control of insect parasites of animals and humans. Acaricides, which kill mites and ticks, are not strictly insecticides, but are usually classified together with insecticides. Some insecticides (including common bug sprays) are effective against other non-insect arthropods as well, such as scorpions, spiders, etc. Insecticides are distinct from insect repellents, which repel but do not kill. Sales In 2016 insecticides were estimated to account for 18% of worldwide pesticide sales. Worldwide sales of insecticides in 2018 were estimated as $ 18.4 billion, of which 25% were neonicotinoids, 17% were pyrethroids, 13% were diamides, and the rest were many other classes which sold for less th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fumigation
Fumigation is a method of pest control or the removal of harmful microorganisms by completely filling an area with gaseous pesticides, or fumigants, to suffocate or poison the pests within. It is used to control pests in buildings (structural fumigation), soil, grain, and produce. Fumigation is also used during the processing of goods for import or export to prevent the transfer of exotic organisms. Structural fumigation targets pests inside buildings (usually residences), including pests that inhabit the physical structure itself, such as woodborers and drywood termites. Commodity fumigation, on the other hand, is also to be conducted inside a physical structure, such as a storage unit, but it aims to eliminate pests from infesting physical goods, usually food products, by killing pests within the container which will house them. Each fumigation lasts for a certain duration. This is because after spraying the pesticides, or fumigants, only the pests around are eradicated. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dow Chemical Company
The Dow Chemical Company is an American multinational corporation headquartered in Midland, Michigan, United States. The company was among the three largest chemical producers in the world in 2021. It is the operating subsidiary of Dow Inc., a publicly traded holding company incorporated under Delaware law. With a presence in around 160 countries, it employs about 36,000 people worldwide. Dow has been called the "chemical companies' chemical company", as its sales are to other industries rather than directly to end-use consumers. Dow is a member of the American Chemistry Council. In 2015, Dow and fellow chemical company DuPont agreed to a corporate reorganization involving the merger of Dow and DuPont followed by a separation into three different entities. The plan commenced in 2017, when Dow and DuPont merged to form DowDuPont, and was finalized in April 2019, when the materials science division was spun off from DowDuPont and took the name of the Dow Chemical Company. H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
