• Following a review by the European Parliament, the REACH Restriction on aliphatic and aromatic diisocyanates (HDI, MDI, TDI, etc.) was published on August 4th, 2020 and became effective on August 24th 2020. (intertronics.co.uk)
  • The unique feature common to all diisocyanate s is that they consist of two N=C=O ( isocyanate ) functional groups attached to an aromatic or aliphatic parent compound. (cdc.gov)
  • These are made from mixed aromatic and aliphatic resins that are hydrogenated to produce a wide range of materials with low colour, high stability and broad compatibility. (synthomer.com)
  • Isocyanates are classified based on the number of N=C=O more aromatic rings) or saturated (aliphatic and alicyclic), groups in the molecule into monoisocyanates (one NCO), the term aliphatic isocyanate referring to saturated isocya- diisocyanate monomers (two NCO), or polyisocyanates nates. (cdc.gov)
  • 16S lignin-derived mixtures of aromatic molecules. (lu.se)
  • What we have demonstrated here is that white-rot fungi can actually utilize lignin-derived aromatic compounds as a carbon source, which means they can eat them and utilize them to grow," Salvachúa said. (pharmamicroresources.com)
  • Through the use of genomic analysis, isotopic labeling, and systems biology approaches, the researchers determined the ability of these organisms to incorporate carbon from lignin-derived aromatic compounds into central metabolism and were able to map out the potential aromatic catabolic pathways for that conversion process. (pharmamicroresources.com)
  • A nucleic acid is a biopolymer composed of monomeric units of nucleotides. (biologyonline.com)
  • Nucleobase comprised by monomeric units nucleotides, DNA is a biopolymer organic compound. (notesbard.com)
  • Salvachúa's work forms the foundation of a new research area based on lignin being broken down by white-rot fungi, which could be further exploited to simultaneously convert the biopolymer into value-added compounds. (pharmamicroresources.com)
  • An oligonucleotide is a compound comprised of about three to twenty nucleotides. (biologyonline.com)
  • A term peroxide I apply to those oxygen-containing compounds whose function is similar to that of hydrogen peroxide and whose molecules contain at least one -O-O- group. (msu.ru)
  • For instance, it could be a source of bifunctional aromatic molecules, like the monocyclic compounds catechol or guaiacol, or bifunctional oligomers. (scirp.org)
  • The biomass raw material consists of a large number of different chemical compounds - both small molecules and large (macro)molecules. (lu.se)
  • Cellulose and hemicellulose are carbohydrates (although variously modified in hemicellulose), while lignin is a complex macromolecule composed of short aromatic molecules. (lu.se)
  • A large number of compounds have been reported as anti-microtubule or anti-actin agents, but only a few compounds have been clarified as to their binding sites on target molecules and their inhibition mechanisms. (go.jp)
  • Furthermore, some compounds show new inhibition mechanisms by binding on novel sites in target molecules. (go.jp)
  • Phenolic compounds are an important class of plant secondary metabolites which play crucial physiological roles throughout the plant life cycle. (mdpi.com)
  • Because of the highly unsaturated nature of the isocyanate functional group, the diisocyanate s readily react with compounds containing active hydrogen atoms (electrophiles). (cdc.gov)
  • The diisocyanate monomers are important commercially the most important aromatic isocyanates, because the two NCO groups allow them to undergo direct whereas 1,6-HDI, isophorone diisocyanate (IPDI), methyle- polymerization reactions with alcohols to form polyur- nedicyclohexyl diisocyanate (HMDI), and their higher ethanes, in addition to enabling prepolymerization reactions polymers are the most important aliphatic isocyanates. (cdc.gov)
  • While both purines and pyrimidines are heterocyclic aromatic compounds, they can be differed from each other based on the chemical structure. (biologyonline.com)
  • A nucleobase is a nitrogen-containing compound. (biologyonline.com)
  • It is an organic compound made up of three subunits: a nucleobase (either a purine or a pyrimidine), a five-carbon sugar (pentose), and a phosphate group . (biologyonline.com)
  • Each monomeric unit component is comprised of a nucleobase, a pentose moiety, and phosphate group. (biologyonline.com)
  • Nucleotide is the monomeric unit of nucleic acid, e.g. (biologyonline.com)
  • For the formation of this bond, a 5′-phosphoric group of a nucleotide is esterified with the 3′-hydroxyl of the next monomeric nucleotide. (notesbard.com)
  • Polyurethane products, including adhesives and potting compounds, are made by reacting diisocyanates and polyols . (intertronics.co.uk)
  • The concentration of monomeric diisocyanates is less than 0.1% by weight, so training is not required if you specify those products. (intertronics.co.uk)
  • HDI, particularly those such as hydrolysis, which involve reaction with active hydrogen compounds and addition to the carbon-nitrogen double bond of the highly reactive isocyanate group. (cdc.gov)
  • In vitro, monomeric UMPS, with a sedimentation coefficient S20,w of 3.6 will become a dimer, S20,w = 5.1 after addition of anions such as phosphate. (wikipedia.org)
  • In an in vitro antimicrobial assay of the crude extracts, the isolated compounds were made against four bacterial strains ( S. aureus ATCC 25923, B. subtilis ATCC 6633 , E. coli ATCC 35218, and P. aeruginosa ATCC 27853) and Fusarium spp. (hindawi.com)
  • This is achieved either through the synthesis of compounds such as diacetyl and esters or by liberating bound aroma compounds such as glycoside-bound primary aromas and volatile thiols which are odorless in their bound form. (frontiersin.org)
  • OH and maintains a reservoir of low-volatility compounds including monomeric sulfate esters and oligomer fragments. (nsf.gov)
  • This allows enzymes the possibility to modify the structure or hydrolyze the polymers into shorter fragments such as monomeric sugars. (lu.se)
  • The Quelet reaction is an important step in the polymerization of aromatic monomers, such as styrene, PPO and PPEK. (wikipedia.org)
  • Polyisocyanates: Species possessing free isocyanate groups and derived from monomeric isocyanate s either by directly linking these monomeric units (a homopolymer) or by reacting these monomers with di- or poly-functional alcohols or amines (a copolymer). (cdc.gov)
  • In general, the types of exposures encountered during the use of iso-cyanates (i.e., monomers, prepolymers, polyisocyanates, and oligomers) in the workplace are related to the vapor pressures of the individual compounds. (cdc.gov)
  • This reduction was accompanied with remarkable changes in the pools of aromatic compounds that accumulate in the biomass. (biomedcentral.com)
  • Several strategies have been proposed, such as the engineering of crop feedstocks to facilitate their deconstruction into monomeric constituents, the use of effective solubilizing solvents for biomass pretreatment, and the cultivation of robust microbial strains tolerant to lignocellulosic inhibitors that are commonly present in biomass hydrolysates [ 6 ]. (biomedcentral.com)
  • Several genetic engineering strategies have been proposed and implemented in crops to reduce lignin content or modify the monomeric composition toward reducing biomass recalcitrance [ 11 , 12 ]. (biomedcentral.com)
  • These results contribute to a better more biomass-derived carbohydrates are also used for produc- understanding of the aromatic metabolism of P. putida in tion of chemicals, a further valorization of lignin is an essential terms of growth and uptake rates, which will be helpful for component. (lu.se)
  • Lignin, an aromatic macromolecule, may play an important role in that exchange, as it is the only bio based source of aromatic compounds. (scirp.org)
  • 2,4,5-Trimethoxybenzoic acid is a compound identified in purple perilla extracts. (medchemexpress.com)
  • Therefore, herein, we purpose the current project to carry out isolation and characterization of compounds from the root of Kniphofia insignis and evaluate their antimicrobial activities. (hindawi.com)
  • Not all aromatic compounds can undergo Quelet reactions. (wikipedia.org)
  • For example, too highly halogenated aromatic compounds, aromatic compounds with nitro groups, and terphenyls cannot be used as reactants for Quelet reactions. (wikipedia.org)
  • Even for compounds that can undergo Quelet reactions, there sometimes exists other reactions that produce the same products in higher yields. (wikipedia.org)
  • Bacterial metabolism selected lignin model compounds (vanillin, vanillate, 4- hydroxybenzoate, p-coumarate, benzoate, and ferulate) was carried out with three of the Pseudomonas isolates and in addition with the strain Pseudomonas putida KT2440 from a Introduction culture collection. (lu.se)
  • Department of Chemical Engineering, Lund University, derived compounds. (lu.se)
  • One of anionic dca ligands in compound 3 is also randomly orientated. (ua.pt)
  • The Cp− ligands of the compound can be readily modified to incorporate various functional groups. (thechemistrynotes.com)
  • Low olefin content, presence of olefin compounds undergo auto-oxidation leading to surface depositions. (bioenergyconsult.com)
  • The individual detector responses for the compounds in the hydrolysates additionally complicate the quantification as pure standards for 4- O -methyl-α-D-glucuronic acid (meGlcA) and related oligosaccharides are not commercially available for calibration. (degruyter.com)
  • Flavonoids are a large family of polyphenolic plant compounds. (oregonstate.edu)
  • Enzymes of various catalytic functions in Streptomyces are useful as members of an artificial gene cluster constructed in Escherichia coli for fermentative production of plant-specific flavonoids, including isoflavones and unnatural compounds. (go.jp)
  • The growth curve reflected a diauxic growth other uses for it, in particular lignosulfonates originating from when mixtures of the model compounds were used as carbon the sulfite pulping process, but the predominant technical lig- source. (lu.se)
  • To investigate the use of lignin products in epoxies, we begin with aromatic acids that can be produced from lignin, treat them with epichlorohydrin to make glycidyl ethers, and investigate the thermal and mechanical properties of cured mixtures of these compounds with a commercial epoxy resin (EPON 826) and an anhydride curing agent (NMA). (acs.org)
  • It is the only bio based macro molecule which contains aromatic structures. (scirp.org)
  • The structures of these compounds were established based on the spectroscopic analyses including NMR ( 1 H-NMR and 13 C-NMR and infrared) and comparison with reported literatures. (hindawi.com)
  • Some of the enzymes which generate aromatic radicals that break down most prominent bacterial strains found were isolated and tax- the complex linkages present in lignin to compounds of lower onomically identified using 16S ribosomal RNA (rRNA) se- molecular weight. (lu.se)
  • The π electrons of the phenyl group can interact with the aromatic ring(s) of an analyte to increase retention relative to non-aromatic species. (ymcamerica.com)
  • Other parts of the plant, such as cellulose, are also recalcitrant but can be fully depolymerized to single monomeric species for use as a biofuel and biochemical precursors, for example. (pharmamicroresources.com)
  • Compound 4 possesses a zig-zag 1D chain structure and a 3D framework is generated through weak interactions between aromatic rings of adjacent layers. (ua.pt)
  • alpha-Asarone (α-Asarone) is one of the main psychoactive compounds, and possesses an antidepressant-like activity in mice. (medchemexpress.com)
  • Generally, most organic compounds are neutral, and therefore more soluble in organic solvents than they are in water. (takebacknigeria.org)
  • Compound 3 consists of neutral distorted octahedral monomeric units and these monomeric units are connected through intermolecular hydrogen bonding, forming a 3D network. (ua.pt)
  • These chloromethylated aromatic polymers are used in a diverse set of industries, such as fuel cells and membranes for drug delivery. (wikipedia.org)
  • He proposed that light caused the reaction between CO 2 and H 2 O whose primary products were a peroxide-type compound percarbonic acid and formaldehyde. (msu.ru)
  • Triglochinic acid is a monomeric compound isolated from tubers of Pinellia pedatisecta Schott. (medchemexpress.com)
  • Dodt G, Kim DG, Reimann SA, Reuber BE, McCabe K, Gould SJ, Mihalik SJ: L-Pipecolic acid oxidase, a human enzyme essential for the degradation of L-pipecolic acid, is most similar to the monomeric sarcosine oxidases. (hmdb.ca)
  • Because of its unique "sandwich" structure, it sparked a surge of interest in compounds involving d-block metals and hydrocarbons, which in turn led to the formation of the now-thriving field of organometallic chemistry. (thechemistrynotes.com)
  • These 2 types differ in respect to their chemical structure and they both constitute aromatic heterocyclic compounds. (notesbard.com)
  • separated into different fractions of chemical compounds. (lu.se)
  • The chemical formula for ferrocene is represented as Fe(C 5 H 5 ) 2 , and it is classified as an organometallic compound. (thechemistrynotes.com)
  • Ferrocene was found in 1951 using the same random process that led to the discovery of the bulk of chemical compounds. (thechemistrynotes.com)
  • The Brachetto variety is the most important aromatic red grape used for the production of sweet sparkling wines in Italy. (unicatt.it)
  • YMC-Pack Ph produces different separation characteristics from alkyl-silica stationary phases (C18, C8, C4) for analytes with aromatic rings due to the π - π and hydrophobic interactions contributing to the separation. (ymcamerica.com)
  • Compounds 2 and 5 have similar molecular connectivity to a previously reported structure, but with a different combination of metal centres. (ua.pt)
  • Using ab initio molecular orbital calculations (HF/6-31G*), the minimum energy structure for unsolvated monomeric 11 was determined to be a C2 symmetric molecule, I, where the faces of both phenyl groups are directed towards the metal, maximising the Li-aromatic interactions. (strath.ac.uk)
  • Compound 1 is made up of a [Fe(bpy)(3)OH](+) cation layer and a [dca center dot 4H(2)O](-) anion layer. (ua.pt)
  • Significant progress is being made, and methods for deconstructing lignin are producing good yields of small, mononuclear aromatic products-sufficient amounts to enable studies of the potential use of these compounds as replacements for compounds currently produced from petroleum. (acs.org)
  • VertiBond™ 5 has a slightly higher polarity than VertiBond™ 1, results in better selectivity for aromatic compounds, acidic and basic compounds and is generally the best choice when developing a method. (vertichrom.com)
  • All of the potential exposures to this compound are associated with the production, handling, use, and disposal of HDI and HDI-containing products or materials. (cdc.gov)
  • However, no process for the production of aromatics from lignin in technical scale has been established until now. (scirp.org)
  • The Quelet reaction is an example of a larger class of reaction, electrophilic aromatic substitution. (wikipedia.org)
  • The reaction was first reported using zinc(II) chloride, however the reaction has been noted to proceed in the absence of this catalyst in highly activated aromatic compounds. (wikipedia.org)
  • If using an aromatic compound where the para-site is blocked, the reaction will add in the ortho-position (see example right). (wikipedia.org)
  • The Quelet reaction can produce dangerous halomethyl ethers, gaseous and liquid compounds that are toxic to humans, and therefore is sometimes passed up for chloromethylations without these harmful biproducts. (wikipedia.org)
  • Blanc reaction Electrophilic aromatic substitution Friedel-Crafts Alkylation Wang, Zerong (2009). (wikipedia.org)
  • The family Asphodelaceae is a rich source of mainly anthraquinones, monomeric and dimeric anthraquinones, anthrones, dimeric phenylanthraquinones, [ 5 ] and naphthoquinone [ 4 ]. (hindawi.com)
  • First, the carbonyl is protonated forming a highly reactive protonated aldehyde that acts as the electrophile to the nucleophilic pi-bond of the aromatic ring. (wikipedia.org)
  • The crystallization of these compounds depends highly on the experimental conditions. (ua.pt)
  • Activation of oxygen might occur due to intermediate formation of peroxides, which always appear during slow oxidation processes, no matter what is the nature of the oxidizing compound. (msu.ru)
  • 1β,4β,7α-Trihydroxyeudesmane (compound 4) is a nature product that could be isolated from the rhizomes of Homalomena occulta . (medchemexpress.com)
  • therefore, there is a need to assess the potential for human exposure to prepolymeric HDI as well as monomeric HDI. (cdc.gov)
  • Electrolysis of molten compounds is Class 5: If K D is equal to 1, equivalent con-centrations exist in each phase. (takebacknigeria.org)
  • It is believed that the two separate catalytic sites fused into a single protein to stabilize its monomeric form. (wikipedia.org)
  • Lignin is one of the most common organic compounds in the world. (scirp.org)
  • The coffee and tea examples are both of the liquid/solid type in which a compound (caffeine) is The distribution of a solute between two phases is an equilibrium condition. (takebacknigeria.org)
  • The coffee and tea examples are both of the liquid/solid type in which a compound (caffeine) is isolated from a solid mixture by using a liquid extraction solvent (water). (takebacknigeria.org)
  • Some of these compounds are examples of metallocenes. (thechemistrynotes.com)
  • 10 minutes) in water and moist soil or sediment to form an amine (i.e., 1,6-hexamethylene diamine) and polyurea compounds. (cdc.gov)
  • 4-Methoxyphenethyl alcohol, an aromatic alcohol, is the major component in the anise-like odour produced by Amorphophallus . (medchemexpress.com)