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Age and origin of the source material determine the chemical structure of humic substances. In general, humic substances derived from soil and peat (which takes hundreds to thousands of years to form) have higher molecular weight, higher amounts of O and N, more carbohydrate units, and fewer polyaromatic units than humic substances derived from ...
Vertisols of the world A more detailed map of the global distribution of Vertisols. A vertisol is a Soil Order in the USDA soil taxonomy [1] and a Reference Soil Group in the World Reference Base for Soil Resources (WRB). [2] It is also defined in many other soil classification systems. In the Australian Soil Classification it is called ...
Piperonal can be prepared by the oxidative cleavage of isosafrole or by using a multistep sequence from catechol or 1,2-methylenedioxybenzene.Synthesis from the latter chemical is accomplished through a condensation reaction with glyoxylic acid followed by cleaving the resulting α-hydroxy acid with an oxidizing agent.
List of inorganic compounds. 18 languages. ... Although most compounds are referred to by their IUPAC systematic names (following IUPAC nomenclature), ...
Heterocyclic organic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of organic heterocycles. [ 2 ] Examples of heterocyclic compounds include all of the nucleic acids , the majority of drugs, most biomass ( cellulose and related materials), and many natural and synthetic dyes.
Exceptions include bisphenol S, P, and M. "Bisphenol" is a common name; the letter following denotes the variant, which depends on the additional substituents. Bisphenol A is the most popular representative of the group, with millions of metric tons produced globally in the past decade, often simply called "bisphenol". [3] [4] [5]
Nepetalactone is a name for multiple iridoid analog stereoisomers. Nepetalactones are produced by Nepeta cataria and many other plants belonging to the genus Nepeta, in which they protect these plants from herbivorous insects by functioning as insect repellents. They are also produced by many aphids, in which they are sex pheromones. [1]
Most research on anthropogenic soils describes specific aspects of their biology, chemistry or physical properties, cultural heritage and human geography, erosion, wastes, pollution, fertilizer management, and taxonomy. Very few of them, [3] [4] [5] try to answer to the question: How fast do they start pedogenesis (viz., differentiating horizons)?