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Metaldehyde
Metaldehyde is an organic compound with the chemical formula, formula (). It is used as a pesticide against slugs and snails. It is the cyclic tetramer of acetaldehyde. Production and properties Metaldehyde is flammable, toxic if ingested in large quantities, and irritating to the skin and eyes. It has a white crystalline appearance with a menthol odor. Metaldehyde is obtained in moderate yields by treatment of acetaldehyde with chilled mineral acids. The liquid trimer, paraldehyde is also obtained. The reaction is reversible; upon heating to about 80 °C, metaldehyde and paraldehyde revert to acetaldehyde. Metaldehyde exists as a mixture of four stereoisomers, molecules that differ with respect to the relative orientation of the methyl groups on the 8-membered ring. The stereoisomers have respectively the molecular symmetries C (with symmetry of order 2), C (order 4), D (order 8), and C (order 8). All have at least one plane of reflexion, so none of them is chiral. Use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molluscicide
Molluscicides () are chemicals that kill molluscs. They are also known as snail baits, snail pellets, or slug pellets. These pesticides against molluscs are usually used in agriculture or gardening, in order to control Pest (organism)#Gastropods, gastropod pests specifically slugs and snails which damage crops or other valued plants by feeding on them. A number of chemicals can be employed as a molluscicide: * Quicklime slaked lime, and kainite, respectively kill by dehydration. Hundreds of kilograms per hectare are required. * Metal salt (chemistry), salts such as iron(III) phosphate, aluminium sulfate, and ferric sodium EDTA, relatively non-toxic, most are approved for use in organic gardening * Metaldehyde * Niclosamide * Acetylcholinesterase inhibitors (e.g. methiocarb), highly toxic to other animals and humans with a quick onset of toxic symptoms. Many chemicals have been developed as molluscicides. Slug pellets contain a carbohydrate source (e.g. Durum, durum flour) as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetaldehyde
Acetaldehyde (IUPAC systematic name ethanal) is an organic compound, organic chemical compound with the chemical formula, formula , sometimes abbreviated as . It is a colorless liquid or gas, boiling near room temperature. It is one of the most important aldehydes, occurring widely in nature and being produced on a large scale in industry. Acetaldehyde occurs naturally in coffee, bread, and ripe fruit, and is produced by plants. It is also produced by the partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase and is a contributing cause of hangover after alcohol (drug), alcohol consumption. Pathways of exposure include air, water, land, or groundwater, as well as drink and smoke. Consumption of disulfiram inhibits acetaldehyde dehydrogenase, the enzyme responsible for the metabolism of acetaldehyde, thereby causing it to build up in the body. International Agency for Research on Cancer, The International Agency for Research on Cancer (IARC) has listed acetaldehyde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetals
In organic chemistry, an acetal is a functional group with the connectivity . Here, the R groups can be organic fragments (a carbon atom, with arbitrary other atoms attached to that) or hydrogen, while the R' groups must be organic fragments not hydrogen. The two R' groups can be equivalent to each other (a "symmetric acetal") or not (a "mixed acetal"). Acetals are formed from and convertible to aldehydes or ketones and have the same oxidation state at the central carbon, but have substantially different chemical stability and reactivity as compared to the analogous carbonyl compounds. The central carbon atom has four bonds to it, and is therefore saturated and has tetrahedral geometry. The term ketal is sometimes used to identify structures associated with ketones (both R groups organic fragments rather than hydrogen) rather than aldehydes and, historically, the term acetal was used specifically for the aldehyde-related cases (having at least one hydrogen in place of an R on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferric Sodium EDTA
Ferric sodium EDTA, also known as sodium ferric ethylenediaminetetraacetate, is a broad spectrum molluscicide used to kill snails and slugs and protect agricultural crops and garden plants, and in particular to eliminate infestations of ''Cornu aspersum'', the common garden snail. Chemically, it is a salt of ethylenediaminetetraacetic acid (EDTA). Mechanism of action and environmental impacts Ferric sodium EDTA works by interacting with and destroying hemocyanin, a copper based compound found in the blood of molluscs and arthropods which is used to carry oxygen, similar to hemoglobin found in vertebrates, and typically kills snails and slugs in a matter of days following exposure. The compound is much safer than Metaldehyde Metaldehyde is an organic compound with the chemical formula, formula (). It is used as a pesticide against slugs and snails. It is the cyclic tetramer of acetaldehyde. Production and properties Metaldehyde is flammable, toxic if ingested in large ... and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lonza Group
Lonza Group AG is a Swiss multinational manufacturing company for the pharmaceutical, biotechnology and nutrition sectors, headquartered in Basel, with major facilities in Europe, North America and South Asia. Lonza was established under that name in the late 19th-century in Switzerland. The company provides product development services to the pharmaceutical and biologic industries, including custom manufacturing of biopharmaceuticals and detection systems and services for the bioscience sector. History Lonza was founded in 1897 in the small Swiss town of Gampel, situated in the canton of Valais, taking its name from the nearby river. In the course of the 20th century Lonza evolved from hydroelectricity and C2 chemistry, through nitrogen chemistry to petrochemistry before moving into fine chemistry and biochemistry. Initially, the company produced electricity. Lonza moved to neighbouring Visp (where it retains a production site today) in 1909. Competition from electric lighting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen Heterocycles
Oxygen is a chemical element; it has symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and a potent oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is the most abundant element in Earth's crust, making up almost half of the Earth's crust in the form of various oxides such as water, carbon dioxide, iron oxides and silicates.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. It is the third-most abundant element in the universe after hydrogen and helium. At standard temperature and pressure, two oxygen atoms will bind covalently to form dioxygen, a colorless and odorless diatomic gas with the chemical formula . Dioxygen gas currently constitutes approximately 20.95% molar fraction of the Earth's atmosphere, though this has changed considerably over long periods of time in Earth's history. A much rarer triat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A Wikimanual Of Gardening/Slugs
A, or a, is the first letter and the first vowel letter of the Latin alphabet, used in the modern English alphabet, and others worldwide. Its name in English is '' a'' (pronounced ), plural ''aes''. It is similar in shape to the Ancient Greek letter alpha, from which it derives. The uppercase version consists of the two slanting sides of a triangle, crossed in the middle by a horizontal bar. The lowercase version is often written in one of two forms: the double-storey and single-storey . The latter is commonly used in handwriting and fonts based on it, especially fonts intended to be read by children, and is also found in italic type. In English, '' a'' is the indefinite article, with the alternative form ''an''. Name In English, the name of the letter is the ''long A'' sound, pronounced . Its name in most other languages matches the letter's pronunciation in open syllables. History The earliest known ancestor of A is ''aleph''—the first letter of the Phoenician ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraldehyde
Paraldehyde is the cyclic trimer (chemistry), trimer of acetaldehyde molecules. Formally, it is a derivative of 1,3,5-trioxane, with a methyl group substituted for a hydrogen atom at each carbon. The corresponding tetramer is metaldehyde. A colourless liquid, it is sparingly soluble in properties of water, water and highly soluble in ethanol. Paraldehyde slowly oxidizes in air, turning brown and producing an odour of acetic acid. It attacks most plastics and rubbers and should be kept in glass bottles. Paraldehyde was first observed in 1835 by the German chemist Justus Liebig; its empirical formula was determined in 1838 by Liebig's student Hermann von Fehling, Hermann Fehling. The German chemist Valentin Hermann Weidenbusch (1821–1893), another of Liebig's students, synthesized paraldehyde in 1848 by treating acetaldehyde with acid (either sulfuric or nitric acid) and cooling to 0°C. He found it quite remarkable that when paraldehyde was ''heated'' with a trace of the same ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methiocarb
Methiocarb is a carbamate pesticide (an acetylcholinesterase inhibitor) which is used as an insecticide, bird repellent, acaricide and molluscicide since the 1960s. Methiocarb has contact and stomach action on mites and neurotoxic effects on molluscs. Seeds treated with methiocarb also affect birds. Other names for methiocarb are mesurol and mercaptodimethur. Due to its toxicity, methiocarb approval as a plant protection product has been withdrawn by the EU effective 2020. Structure and reactivity The carbamate functional group in methiocarb can be cleaved by cholinesterase to result in the carbamate, which binds to the cholinesterase, and the phenol. Synthesis Methiocarb (3) is synthesised by Bayer from 4-methylthio-3,5-xylenol (1) and methyl isocyanate (2). The xylenol (1) will act as the nucleophile in this reaction attacking the partially positively charged carbon in the isocyanate (2). Mechanism of action Methiocarb acts by acetylcholinesterase inhibition. The pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bitterant
A bitterant (or bittering agent) is a chemical that is added to a product to make it olfaction, smell or taste Taste#Bitterness, bitter. Bitterants are commonly used as aversive agents to discourage the inhalation or ingestion of toxic substances. Examples of use *The addition of a bitterant to ethanol Denatured alcohol, denatures the product. *Bitterants are used in antifreeze to prevent pet and child poisonings. It is required by law in some places (France, Oregon, etc.). *Gas dusters often use a bitterant to discourage inhalant abuse, although this can cause problems for legitimate users. The bitterant not only leaves a bitter flavor in the air, but also leaves a bitter residue on objects, like screens and keyboards, that may transfer to hands and cause problems (such as when eating). *Nintendo game card#Nintendo Switch, Game cartridges for the Nintendo Switch are coated with denatonium as a safety feature to deter small children from Pica (disorder), ingesting them. *Some but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interwar Period
In the history of the 20th century, the interwar period, also known as the interbellum (), lasted from 11 November 1918 to 1 September 1939 (20 years, 9 months, 21 days) – from the end of World War I (WWI) to the beginning of World War II (WWII). It was relatively short, yet featured many social, political, military, and economic changes throughout the world. Petroleum-based energy production and associated mechanisation led to the prosperous Roaring Twenties, a time of social mobility, social and economic mobility for the middle class. Automobiles, electric lighting, radio, and more became common among populations in the developed world, first world. The era's indulgences were followed by the Great Depression, an unprecedented worldwide economic downturn that severely damaged many of the world's largest economies. Politically, the era coincided with the rise of communism, starting in Russia with the October Revolution and Russian Civil War, at the end of WWI, and ended with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
