Tag: M.W=250-300

Zhang, Xiao-Juan published the artcileIdentification of age-markers based on profiling of Baijiu volatiles over a two-year maturation period: Case study of Lu-flavor Baijiu, Computed Properties of 41114-00-5, the main research area is Lu flavor Baijiu volatile maturation period identification.

Baijiu is a highly-valued traditional Chinese distilled alc. liquor and maturation markedly improves its sensory qualities and market value. Identification of age-markers is challenging because of the complexity of the endogenous chem. profile and the absence of exogenous components added during maturation. Here, freshly-distilled raw Lu-flavor Baijiu samples were stored for two years and non-targeted screening for age-markers based on the volatile profile characterized by solid-phase micro-extraction assisted GC-MS. The resulting volatile datasets were analyzed by partial least-squares discriminant anal., Spearman’s correlation and Random-forest decision-tree, to identify potential age-markers. The contents of long chain fatty acid Et esters varied the most during maturation, mostly being absent in freshly-distilled Baijiu, but appearing at different times. Similar behavior was observed in bottled samples matured up to four years. In addition, a slight increase in short/medium chain fatty acid ester content was observed Unsupervised PCA anal., applied only to the fatty acid Et ester dataset, was able to distinguish between bottled Baijiu samples matured for one, two, three, or four years. These age-markers may help establish a reliable model for verifying the maturation time of Lu-flavor Baijiu. This screening approach should be adaptable to other alc. liquors, for quality assessment and authenticity testing.

LWT–Food Science and Technology published new progress about Alcoholic beverages. 41114-00-5 belongs to class esters-buliding-blocks, name is Ethyl pentadecanoate, and the molecular formula is C17H34O2, Computed Properties of 41114-00-5.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Matsumoto, Mayuko published the artcileSelf-assembly of amphiphilic block pendant polymers as microphase separation materials and folded flower micelles, Product Details of C16H30O2, the main research area is self assembly amphiphilic polymer microphase separation folded flower micelle.

Herein, we created amphiphilic polymers bearing hydrophilic/hydrophobic block pendants as a new class of self-assembled materials for microphase separation in the solid state and forming folded flower micelles in water. For this, we designed amphiphilic block methacrylates comprising hydrophilic poly(ethylene glycol) (PEG) and a hydrophobic dodecyl group: DPEG10MA and DPEG23MA. The DPEG10MA and DPEG23MA homopolymers induced microphase separation of the block pendants. For example, the DPEG23MA homopolymer formed lamellar structures; the hydrophilic and crystallized PEG and hydrophobic dodecyl units are alternately layered with about 14 nm domain spacing. In water, random copolymers of PEG Me ether methacrylate and DPEG10MA folded into flower micelles with both looped and linear PEG shells, where the dodecyl groups of the incorporated DPEG10MA assembled to form hydrophobic cores. The micelles further showed thermoresponsive solubility in water. The size, aggregation number, and cloud point of the micelles were controlled by their composition and chain length.

Polymer Chemistry published new progress about Aggregation. 142-90-5 belongs to class esters-buliding-blocks, name is Dodecyl 2-methylacrylate, and the molecular formula is C16H30O2, Product Details of C16H30O2.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Cuevas-Glory, Luis published the artcileCharacterization of odor-contributing volatiles in two Habanero pepper varieties by gas chromatography-olfactometry, Application of Ethyl pentadecanoate, the main research area is Habanero pepper odor volatile compound gas chromatog olfactometry.

Abstract: Volatile constituents and odor-active compounds of two varieties of Habanero pepper (Capsicum chinense Jacq.) were analyzed by GC-MS, GC-O and AEDA. A total of 118 volatile compounds were obtained from Habanero pepper varieties Mayapan and Jaguar by simultaneous distillation-extraction technique. Compounds such as esters, terpenes, aldehydes, alcs. and ketones comprised 78% of volatiles found in both varieties. By means of AEDA technique, 24 odor-contributing compounds (esters, terpenes, aldehydes and alcs.) were identified. Compounds such as δ-cadinene (FD = 729), 3-methylbutyl 2-methylpropanoate and 3,3-dimethylcyclohexanol (FD = 243) were the major odor-active compounds in Mayapan variety aroma, whereas 3-methylbutyl 2-methylpropanoate (FD = 729) and 2-methylpropyl 2-methylbutanoate, hexyl pentanoate and δ-cadinene (FD = 243) were characteristic in Jaguar variety. An intense pungent odor was notorious in Mayapan variety, due mainly to 3,3-dimethylcyclohexanol. On the basis of FD values, sweet and pungent were characteristic notes in Mayapan variety, whereas sweet and fruity notes were predominant in Jaguar variety. This suggests that aroma variability among Habanero pepper varieties might be related to their genotypic diversity.

Chemical Papers published new progress about Alcohols Role: ANT (Analyte), BSU (Biological Study, Unclassified), ANST (Analytical Study), BIOL (Biological Study). 41114-00-5 belongs to class esters-buliding-blocks, name is Ethyl pentadecanoate, and the molecular formula is C17H34O2, Application of Ethyl pentadecanoate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

He, Zhanglan published the artcileTandem Solid-Phase Extraction Columns for Simultaneous Aroma Extraction and Fractionation of Wuliangye and Other Baijiu, Related Products of esters-buliding-blocks, the main research area is Wuliangye Baijiu tandem solid phase aroma extraction; Wuliangye baijiu; fatty acid esters; polar compounds; simultaneous extraction and fractionation; tandem SPE columns.

Wuliangye baijiu is one of the most famous baijiu in China, with a rich, harmonic aroma profile highly appreciated by consumers. Thousands of volatiles have been identified for the unique aroma profile. Among them, fatty acid esters have been identified as the main contributors to the aroma profile. In addition, many non-ester minor compounds, many of which are more polar than the esters, have been identified to contribute to the characteristic aroma unique to Wuliangye baijiu. The anal. of these minor compounds has been challenging due to the dominance of esters in the sample. Thus, it is desirable to fractionate the aroma extract into subgroups based on functional group or polarity to simplify the anal. This study attempts a new approach to achieve simultaneous volatile extraction and fractionation using tandem LiChrolut EN and silica gel solid-phase extraction (SPE) columns. A baijiu sample (10 mL, diluted in 40 mL of water) was first passed through the LiChrolut EN (1.0 g) column. The loaded LiChrolut EN column was then dried with air and coupled with a silica gel (5.0 g) SPE column with anhydrous Na2SO4 (10.0 g) in between. The volatile compounds were eluted from the LiChrolut EN column and simultaneously fractionated on the silica gel column based on polarity. The simultaneous extraction and fractionation technique enabled the fractionations of all fatty acid esters into less polar fractions. Fatty acids, alcs., pyrazines, furans, phenols, hydroxy esters, and other polar compounds were collected in more polar fractions. This technique was used to study the volatile compounds in Wuliangye, Moutai, and Fengjiu baijiu. In addition to fatty acid esters, many minor polar compounds, including 2,6-dimethylpyrazine, 2-ethyl-6-methylpyrazine, 2-ethyl-3,5-dimethylpyrazine, p-cresol, and 2-acetylpyrrole, were unequivocally identified in the samples. The procedure is fast and straightforward, with low solvent consumption.

Molecules published new progress about Baijiu. 41114-00-5 belongs to class esters-buliding-blocks, name is Ethyl pentadecanoate, and the molecular formula is C17H34O2, Related Products of esters-buliding-blocks.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Zhu, Chen published the artcileTowards nanoparticles with site-specific degradability by ring-opening copolymerization induced self-assembly in organic medium, COA of Formula: C16H30O2, the main research area is nanoparticle degradability ring opening copolymerization self assembly organic medium.

Reversible addition-fragmentation chain transfer (RAFT)-mediated radical ring-opening copolymerization-induced self-assembly (rROPISA) in heptane at 15 weight% solids was successfully applied to the copolymerization of benzyl methacrylate (BzMA) with 2-methylene-1,3-dioxepane (MDO) from a poly(lauryl methacrylate) (PLMA) macro-RAFT agent. Despite less efficient control of the copolymerization compared to similar copolymerization with 2-methylene-4-phenyl-1,3-dioxolane (MPDL) or 5,6-benzo-2-methylene-1,3-dioxepane (BMDO), it yielded stable, diblock copolymer nanospheres (Dz = 100-200 nm) containing tunable amounts of polycaprolactone (PCL)-like degradable units in the core (FMDO = 0.04-0.19), resulting in significant degradation under accelerated hydrolytic conditions. Synthesis of surface-degradable diblock copolymer nanoparticles was then performed through the synthesis of P(LMA-co-BMDO) and P(LMA-co-MPDL) macro-chain transfer agents (CTAs). Even though partial livingness during chain extension with BzMA by PISA was noticed, stable nanospheres were obtained for FBMDO = 0.05 and porous nanospheres for FBMDO = 0.08-0.09, whose average diameters increased with the BMDO content. Attempts to prepare “”all-degradable”” vinyl particles were also made by rROPISA of BzMA and BMDO (or MPDL) from degradable macro-CTAs showing degradation in agreement with the copolymers’ expected structure.

Polymer Chemistry published new progress about Chain transfer agents. 142-90-5 belongs to class esters-buliding-blocks, name is Dodecyl 2-methylacrylate, and the molecular formula is C16H30O2, COA of Formula: C16H30O2.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Diez-Fernandez, Alazne published the artcileMosquitoes are attracted by the odour of Plasmodium-infected birds, Product Details of C17H34O2, the main research area is Plasmodium Passer Culex odor; Chemical communication; Host preference; Infectious diseases; Olfaction; Olfactometer; Wild birds.

Avian malaria parasites (Plasmodium) are thought to alter the cues such as host odor, used by host-seeking mosquitoes. Bird odor is affected by secretions from the uropygial gland and may play a role in modulating vector-host interactions. We tested the hypothesis that mosquitoes are more attracted to the uropygial secretions and/or whole-body odor (headspace) of Plasmodium-infected house sparrows (Passer domesticus) than to those of uninfected birds. We tested the attraction of nulliparous (e.g. uninfected mosquitoes without previous access to blood) Culex pipiens females towards these stimuli in a dual-choice olfactometer. We used Gas Chromatog.-Mass Spectrometry (GC-MS) analyses to assess whether Plasmodium infection is associated with differences in the chem. composition of uropygial secretions. Mosquitoes were more attracted to the odours of infected than uninfected birds, regardless of sex. However, the significant interaction between infection status and the stimuli (uropygial secretion or headspace) showed that mosquitoes were more attracted to the headspace of infected birds; no differences were found in the case of uropygial secretions. The compounds in the volatile lipophilic fraction of the uropygial secretion did not differ between infected and uninfected birds. These results support the host manipulation hypothesis since avian Plasmodium parasites may be capable of altering their hosts body odor, thereby making infected individuals more attractive to mosquitoes.

International Journal for Parasitology published new progress about Alcohols Role: ANT (Analyte), BSU (Biological Study, Unclassified), ANST (Analytical Study), BIOL (Biological Study). 41114-00-5 belongs to class esters-buliding-blocks, name is Ethyl pentadecanoate, and the molecular formula is C17H34O2, Product Details of C17H34O2.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Kozawa, Susan K. published the artcileSelf-assembly of amphiphilic ABA random triblock copolymers in water, COA of Formula: C16H30O2, the main research area is self amphiphilic aba random triblock copolymer water.

Self-assembly of amphiphilic ABA random triblock copolymers in water serves as a novel approach to create unique structure micelles connected with flexible linkages. The ABA triblock copolymers consist of amphiphilic random copolymers bearing hydrophilic poly(ethylene glycol) and hydrophobic dodecyl pendants as the A segments and a hydrophilic poly(ethylene oxide) (PEO) as the middle B segment. The A block is varied in dodecyl methacrylate content of 20%-50% and d.p. (DP) of 100-200. By controlling the composition and DP of the A block, various architectures can be tailor-made as micelles in water: PEO-linked double core unimer micelles, PEO-looped unimer or dimer micelles, and multichain micelles. Those PEO-linked or looped micelles further exhibit thermoresponsive solubility in water. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018.

Journal of Polymer Science, Part A: Polymer Chemistry published new progress about Amphiphiles. 142-90-5 belongs to class esters-buliding-blocks, name is Dodecyl 2-methylacrylate, and the molecular formula is C16H30O2, COA of Formula: C16H30O2.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Wang, Chen-Gang published the artcileMetal-Free Fast Azidation by Using Tetrabutylammonium Azide: Effective Synthesis of Alkyl Azides and Well-Defined Azido-End Polymethacrylates, Synthetic Route of 142-90-5, the main research area is Metal fast azidation tetrabutylammonium alkyl azide azido end polymethacrylate; azides; cycloaddition; green chemistry; polymers; synthesis design.

An effective method to synthesize azido-end polymethacrylates from tetrabutylammonium azide (BNN3) in a nonpolar solvent (toluene) was developed. Several low-mass alkyl halides were reacted with BNN3 in toluene as model reactions and the rate constants of these reactions were determined, to confirm fast BNN3 azidation for tertiary and secondary halides. The end-group transformation of halide-end polymethacrylates was effective and nearly quant. Notably, the combination of organocatalyzed living (or reversible deactivation) radical polymerization and BNN3 azidation enabled the metal-free synthesis of azido-end polymethacrylates, including single-azido-end and multi-azido-end functional homopolymers and block copolymers. The rapid and quant. reaction without the requirement for a large excess of BNN3, metal-free and polar-solvent-free nature, and broad polymer scope are attractive features of this azidation.

Chemistry – A European Journal published new progress about Azidation. 142-90-5 belongs to class esters-buliding-blocks, name is Dodecyl 2-methylacrylate, and the molecular formula is C16H30O2, Synthetic Route of 142-90-5.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Patil, Naganatha published the artcileOrthogonally grown polycarbonate and polyvinyl block copolymers from mechanistically distinct (co)polymerizations, COA of Formula: C16H30O2, the main research area is polycarbonate polyvinyl block copolymer.

Mechanistically distinct polymerization systems can afford unique block copolymers that would not be accessible by mere sequential polymerization Herein we report a convenient one-pot synthesis of miscellaneous di- and triblock copolymers comprising CO2-based and polyvinyl blocks, obtained orthogonally through triethylborane (TEB)-mediated ring opening copolymerization (ROCOP) of CO2 with epoxides on the one hand and reversible addition fragmentation chain transfer (RAFT) polymerization of vinyl monomers on the other. 4-Cyano-4-[(dodecylsulfanylthiocarbonyl) sulfanyl] pentanoic acid (TTC-COOH), which carries a trithiocarbonate function and a carboxylic acid group, played the dual role of a chain transfer agent for RAFT polymerization and an initiator for the ROCOP of CO2/epoxide. Different bases such as tetrabutylammonium hydroxide, N-heterocyclic carbene (NHC), and tributylamine (TBA) were used for the deprotonation of TTC-COOH. It was found that the salts produced in situ by the deprotonation of TTC-COOH using NHC and TBA did not harm trithiocarbonate functions. The two distinct polymerizations occurred as expected, affording a series of well-defined CO2-based AB and ABC block copolymers comprising one or two poly(vinyl) blocks, depending upon the choice of different combinations of epoxides and vinyl monomers. The thermal characterization of these AB and ABC block copolymers revealed either two or three glass transition temperatures indicative of phase-separated materials.

Polymer Chemistry published new progress about Acrylic polymers, polycarbonate-, block, triblock Role: PRP (Properties), SPN (Synthetic Preparation), PREP (Preparation). 142-90-5 belongs to class esters-buliding-blocks, name is Dodecyl 2-methylacrylate, and the molecular formula is C16H30O2, COA of Formula: C16H30O2.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Imai, Shota published the artcileSelf-Sorting of Amphiphilic Copolymers for Self-Assembled Materials in Water: Polymers Can Recognize Themselves, Computed Properties of 142-90-5, the main research area is self sorting amphiphilic copolymer micelle assembly hydrogel.

Amphiphilic random copolymers bearing hydrophilic poly(ethylene glycol) (PEG) and hydrophobic alkyl pendants showed dynamic self-sorting behavior, i.e., self-recognition, under competitive conditions in aqueous media. The self-sorting universally takes place not only in water but also in hydrogels and on the material surfaces, according to encoded information originating from the primary structure of composition and pendants. Binary blends of the copolymers with different composition or alkyl pendants readily induced composition- or alkyl pendant-dependent self-sorting to simultaneously provide discrete and size-controlled micelles with hydrophobic cores. Surprisingly, the micelles reversibly keep exchanging polymer chains exclusively between identical polymer micelles even in the presence of different counterparts. Owing to the dynamic self-sorting behavior, ABA-triblock copolymers comprising the amphiphilic random copolymer A segments and a hydrophilic PEG chain B segment further provided hydrogels with self-healing yet selectively adhesive properties.

Journal of the American Chemical Society published new progress about Acrylic polymers, polyoxyalkylene-, graft Role: PRP (Properties), SPN (Synthetic Preparation), PREP (Preparation). 142-90-5 belongs to class esters-buliding-blocks, name is Dodecyl 2-methylacrylate, and the molecular formula is C16H30O2, Computed Properties of 142-90-5.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics