Month: December 2022

Fedin, Igor published the artcileEnhanced Emission from Bright Excitons in Asymmetrically Strained Colloidal CdSe/CdxZn1-xSe Quantum Dots, HPLC of Formula: 142-90-5, the main research area is enhanced emission bright excitons asym colloidal CdSe CdZnSe QD; acoustic phonon; bright exciton; colloidal quantum dot; exciton fine structure; nanocrystal; single-photon emitter.

Colloidal CdSe quantum dots (QDs) designed with a high degree of asym. internal strain have recently been shown to host a number of desirable optical properties including subthermal room-temperature line widths, suppressed spectral diffusion, and high photoluminescence (PL) quantum yields. It remains an open question, however, whether they are well-suited for applications requiring emission of identical single photons. Here, we measure the low-temperature PL dynamics and the polarization-resolved fluorescence line narrowing spectra from ensembles of these strained QDs. Our spectroscopy reveals the radiative recombination rates of bright and dark excitons, the relaxation rate between the two, and the energy spectra of the quantized acoustic phonons in the QDs that can contribute to relaxation processes. In comparison to conventional colloidal CdSe/ZnS core/shell QDs, we find that in asym. strained CdSe QDs over six times more light is emitted directly by the bright exciton. These results are therefore encouraging for the prospects of chem. synthesized colloidal QDs as emitters of single indistinguishable photons.

ACS Nano published new progress about Acoustic phonon. 142-90-5 belongs to class esters-buliding-blocks, name is Dodecyl 2-methylacrylate, and the molecular formula is C16H30O2, HPLC of Formula: 142-90-5.

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

El-Hefnawy, Mohamed E. published the artcileEndogenous bioethanol production by solid-state prefermentation for enhanced crude bio-oil recovery through integrated hydrothermal liquefaction of seaweeds, Application of Ethyl 4-oxopentanoate, the main research area is biomass endogenous bioethanol fermentation oil recovery hydrothermal liquefaction seaweed.

The present study evaluated the action of endogenous bioethanol produced during solid-state fermentation of Ulva spp. on subsequent hydrothermal liquefaction (HTL). HTL of raw biomass (RB) was compared with HTL of the fermented biomass after bioethanol separation (F-Aqua) and HTL of the whole fermentation broth containing the bioethanol (F-Eth). Optimization of fermentation conditions increased the ethanol yield efficiency (Yeff) and specific ethanol yield (SEY) from 23.55% and 0.120 g g-1 sugar consumed to 43.97% and 0.224 g g-1 sugar consumed, resp. TGA and FTIR anal. confirmed noticeable changes in the thermal profile and functional groups of the fermented residue with increased volatiles and lower ash content. Among different HTL treatments, F-Eth showed the highest bio-oil yield of 24.96% at 250°C, which was 37.7% and 39.0% higher than that of RB and F-Aqua, resp. In addition, hydrocarbons and esters in the bio-oil represented the dominant compounds in F-Aqua and F-Eth, altogether 28.28% and 68.58%, resp., compared to 17.96% in RB. Economic anal. for a proposed 100 ton year-1 plant confirmed that HTL of the whole fermentation broth containing endogenous bioethanol enhanced the gross energy output to 8.152 GJ ton-1, which represented 4.2-time, 51.1%, and 23.3% higher than individual bioethanol production, individual bio-oil production, and sequential bioethanol/bio-oil recovery, with the highest net annual profit of 29553 US$ compared to 23391 US$ for the sequential production

Journal of Cleaner Production published new progress about Acid hydrolysis. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Application of Ethyl 4-oxopentanoate.

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

Howard, Micheal Seamus published the artcileEthanolic gasoline, a lignocellulosic advanced biofuel, Related Products of esters-buliding-blocks, the main research area is ethanolic gasoline lignocellulosic biofuel combustion.

In line with society’s growing need for a more sustainable fuel economy, various biofuels and alternative fuel formulations are being proposed. In this work, the ignition quality of a novel tricomponent advanced biofuel is examined Et levulinate, di-Et ether and ethanol (EL/DEE/EtOH) result from the acid hydrolysis of lignocellulosic biomass in ethanol. In this paper, derived cetane numbers are established for a wide variety of blend fractions, using Ignition Quality Tester measurements. EL/DEE/EtOH mixtures of ignition quality equivalent to market diesel and gasoline are identified. One mixture of Motor Octane Number (MON) 88.3 and Research Octane Number (RON) 95 is selected for detailed anal. in comparison to a FACE (Fuels for Advanced Combustion Engines) gasoline, as a representative of petroleum-derived gasoline, with a similar MON of 88.8 and RON of 94.4. Ignition delay times for the EL/DEE/EtOH gasoline fuel are measured using a rapid compression machine at equivalence ratios of 0.5 and 1.0, at 20 and 40 bar over a temperature range of 600-900 K. The data shows that at temperatures >800 K, the EL/DEE/EtOH fuel behaves quite similar to the petroleum derived gasoline, FACE-F. However, the tri-component biofuel shows a dramatically truncated extent of ignition reactivity at lower temperatures, with a total absence of low-temperature chem. or neg. temperature coefficient (NTC) region; in this respect this biofuel blend is very different to conventional gasoline. To understand this differing behavior, a detailed chem. kinetic model is developed. Anal. of this model shows that ignition of the EL/DEE/EtOH blend is inhibited by the dominance of alkyl radical elimination pathways, which leads to a heightened rate of production of HO2 radicals. At high temperatures, while both fuels maintain a similar ignition delay time, the sensitivity anal. and the radical pool population shows that a different combustion mechanism is occurring for the EL/DEE/EtOH fuel, where Et and Me radicals play a much more prominent role in the ignition process.

Sustainable Energy & Fuels published new progress about Acid hydrolysis. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Related Products of esters-buliding-blocks.

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

Liu, Fangtian published the artcileChanges of terpenoids and other volatiles during alcoholic fermentation of blueberry wines made from two southern highbush cultivars, Product Details of C10H20O2, the main research area is terpenoid blueberry wine volatile alc fermentation.

Aroma is one of the most important aspects to determine the wine quality and its market value. Changes of volatile profiles and terpenoid precursors were monitored for blueberry wines made from two different southern high bush cultivars (Misty and O’Neal) during the alc. fermentation using solid phase microextraction-gas chromatog.-quadrupole time of flight-mass spectrometry (SPME-GC-QTOF-MS). Volatile profile of the wine significantly changed as a function of time during fermentation, which was due to the gradual reduction of C6 compounds, extraction and hydrolysis of terpenoids precursors, and generation of esters and alcs. Misty samples contained higher amount of terpenoids compared to the O’Neal samples during the whole fermentation process. E-asarone and Me isoeugenol were only detected in O’Neal samples. Myrtenol, E-carveol and borneol were presented mainly as bound form, while other terpenoids mainly as free form in the final wines, indicating the different resistance of the glycoside to acid hydrolysis during fermentation

LWT–Food Science and Technology published new progress about Acid hydrolysis. 106-32-1 belongs to class esters-buliding-blocks, name is Ethyl octanoate, and the molecular formula is C10H20O2, Product Details of C10H20O2.

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

Roda, Amy published the artcileA new synthetic lure for management of the invasive giant African snail, Lissachatina fulica, COA of Formula: C9H10O2, the main research area is Lissachatina lure fruit flavor oil volatile compound biocontrol.

The goal of this study was to find a synthetic attractant that could aid in the eradication or management of the giant African snail (Lissachatina fulica). Field studies in Hawaii showed that a com. papaya-flavored oil attracted snails. Anal. of the odor profile of the oil identified a total of 22 chems., which comprised > 98% of the volatile compounds emitted by the oil. A synthetic blend was reconstructed that mirrored the release rates of the papaya oil odors. In laboratory and field bioassays, the reconstructed blend, applied to cotton wicks as water and canola oil or water and mineral emulsions, attracted more snails than the water and oil emulsion control wicks. Field studies in Hawaii and Florida showed that the reconstructed blend in an oil emulsion was not attractive to non-target species such as butterflies or bees. The snails were attracted from distances > 1 m and entered traps baited with the attractant emulsion. When tested in the South Florida giant African snail eradication program, direct ground application of the reconstructed papaya-flavored oil emulsion increased the number of snails killed by over 87% compared to water emulsion controls. Integrating tactics using the synthetic papaya oil attractant into control measures should increase the effectiveness of eradication and management programs.

PLoS One published new progress about Achatina fulica. 140-11-4 belongs to class esters-buliding-blocks, name is Benzyl acetate, and the molecular formula is C9H10O2, COA of Formula: C9H10O2.

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

Wang, Yue published the artcileCoupling 16S rDNA Sequencing and Untargeted Mass Spectrometry for Milk Microbial Composition and Metabolites from Dairy Cows with Clinical and Subclinical Mastitis, Category: esters-buliding-blocks, the main research area is dairy milk microbial metabolite mastitis MS; dairy cow; mastitis; metabolomics; microbiota; milk.

The internal environment of the cow′s udder directly affects the udder health and milk quality. 16S rDNA sequencing and liquid chromatog.-mass spectrometry (LC-MS) methods were used to investigate the significant differences in milk microbial diversity and metabolites among cows that are healthy (H) and those suffering from subclin. mastitis (SM) and clin. mastitis (CM). Results uncovered more than 16 and 192 differently abundant microbiota at the phylum and genus levels, resp., and 673 different levels of metabolites enriched in 20 pathways in milk among the 3 groups. This study revealed the pos. relevance between Staphylococcus and Streptococcus and ceramide in milk from CM cows. Similarly, Acinetobacter and Corynebacterium were pos. associated with testosterone glucuronide and 5-methyl-tetrahydrofolate, in milk from SM cows. On the basis of the combined anal. of microbiome and metabolome, this study indicated that, apart from the exogenous pathogens, some beneficial symbiotic bacteria, such as Dietzia, Aeromicrobium, Alistipes, and Sphingobacterium, rarely reported in milk have been found to be significantly reduced during mastitis.

Journal of Agricultural and Food Chemistry published new progress about Acetoanaerobium. 111-11-5 belongs to class esters-buliding-blocks, name is Methyl octanoate, and the molecular formula is C9H18O2, Category: esters-buliding-blocks.

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

Ren, Qing published the artcileThe changes of microbial community and flavor compound in the fermentation process of Chinese rice wine using Fagopyrum tataricum grain as feedstock, Quality Control of 123-29-5, the main research area is microbial community flavor compound Fagopyrum Chinese rice wine fermentation.

Chinese rice wine (CRW), a unique wine species, has a long history in China. Fagopyrum tataricum grain is a kind of high-quality grain with function in health care. The production of CRW wine with F. tataricum grain is beneficial to the development of new rice wine products. The flavor compounds and microorganisms in F. tataricum grain rice wine were studied. One hundred and seven volatile compounds (including 11 kinds of pyrazines that were rarely detected in wine) were detected and eight organic acids were measured. The microecol. diversity in the fermentation process of F. tataricum rice wine was studied. It was found that Bacillus was the main bacterial genus, and the unclassfied_O_Saccharomycetales was the main fungi. Correlation anal. between microorganism and flavor compound shown there are 838 correlations. A total of 108 microbial genera maybe participate in the formation of flavor compounds In addition, fourteen genera included unclassified_O_Saccharomycetales, Lactococcus, Pediococcus, Aspergillus, Cladosporium, Cochliobolus, Sporidiobolus, Pichia and Saccharomycopsis et al. were screened as functional significant microbiota and built correlation with flavor compounds This work provides a perspective for bridging the gap between flavor compound and microbial community, and advances our understanding of mechanisms in F. tataricum rice wine fermentation

Scientific Reports published new progress about Acetoanaerobium. 123-29-5 belongs to class esters-buliding-blocks, name is Ethyl nonanoate, and the molecular formula is C11H22O2, Quality Control of 123-29-5.

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

Aniceto, Jose P. S. published the artcileMachine learning models for the prediction of diffusivities in supercritical CO2 systems, Application of Benzyl acetate, the main research area is carbon dioxide supercritical system machine learning diffusivity.

The mol. diffusion coefficient is fundamental to estimate dispersion coefficients, convective mass transfer coefficients, etc. Since exptl. diffusion data is scarce, there is significant demand for accurate models capable of providing reliable diffusion coefficient estimations In this work we applied machine learning algorithms to develop predictive models to estimate diffusivities of solutes in supercritical carbon dioxide. A database of exptl. data containing 13 properties for 174 binary systems totaling 4917 data points was used in the training of the models. Five machine learning algorithms were evaluated and the results were compared with three commonly used classic models. The best results were found using the Gradient Boosted algorithm which showed an average absolute relative deviation (AARD) of 2.58% (pure prediction). This model has five parameters: temperature, d., solute molar mass, solute critical pressure and solute acentric factor. For the same dataset, the classic Wilke-Chang equation showed AARD of 12.41%. The developed model is provided as command line program.

Journal of Molecular Liquids published new progress about Acentric factor. 140-11-4 belongs to class esters-buliding-blocks, name is Benzyl acetate, and the molecular formula is C9H10O2, Application of Benzyl acetate.

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

Peng, Yaoyao published the artcileCompositional analysis and aroma evaluation of feijoa essential oils from New Zealand grown cultivars, Synthetic Route of 106-32-1, the main research area is Acca essential oil aroma volatile compound; GC-MS; HS-SPME-GC-O-MS; aroma active compounds; aroma profile; feijoa essential oil; hydro-distillation.

Feijoa is an aromatic fruit and the essential oil from feijoa peel could be a valuable byproduct in the juicing industry. An initial comparison of the essential oil extraction methods, steam-distillation and hydro-distillation, was conducted. The volatile compounds in the essential oils from four feijoa cultivars were identified and semi-quantified by GC-MS and the aroma active compounds in each essential oil were characterized using SPME-GC-O-MS. Hydro-distillation, with a material to water ratio of 1:4 and an extraction time of 90 min, was the optimized extraction method for feijoa essential oil. The Wiki Tu cultivar produced the highest essential oil yield among the four selected cultivars. A total of 160 compounds were detected, among which 90 compounds were reported for the first time in feijoa essential oils. Terpenes and esters were dominant compounds in feijoa essential oil composition and were also major contributors to feijoa essential oil aroma. Key aroma active compounds in feijoa essential oils were a-terpineol, Et benzoate, (Z)-3-hexenyl hexanoate, linalool, (E)-geraniol, 2-undecanone, 3-octanone, a-cubebene, and germacrene D. This is the first report on the optimization of the extraction method and the establishment of the aroma profile of feijoa essential oils, with a comparison of four New Zealand grown cultivars.

Molecules published new progress about Acca sellowiana. 106-32-1 belongs to class esters-buliding-blocks, name is Ethyl octanoate, and the molecular formula is C10H20O2, Synthetic Route of 106-32-1.

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

Bera, Paramita published the artcileDevelopmental variation in floral volatiles composition of a fragrant orchid Zygopetalum maculatum (Kunth) Garay, Synthetic Route of 140-11-4, the main research area is Zygopetalum volatile; (Kunth) Garay; benzenoids; headspace scent volatiles; phenylpropanoid.

Emitted scent volatile profile of an orchid species Zygopetalum maculatum was studied using dynamic headspace sampling technique with four different adsorbent matrixes, namely Porapak Type Q polymer (mesh size: 80/100), Tenax (mesh size: 60/80), activated charcoal and graphite. In addition, developmental variations in scent emissions and endogenous volatile levels were also investigated. Gas chromatog.-mass spectrometry anal. revealed the presence of 21 volatile compounds in the headspace, which was predominantly enriched with benzenoid compounds Among these benzenoids, o-diethylbenzene and p-diethylbenzene were the major compounds followed by benzyl acetate and Me salicylate. Among the phenylpropanoid compounds, 2-phenylethyl acetate was the major volatile. However, as compared to benzenoids, the quantity was much lesser, indicating the inclination of phenylalanine flux towards benzenoid pathway. The outcome of this study has the implications in enhancing fragrance and vase life of orchids of the Sikkim Himalaya region and thus may further help to meet the growing market demand.

Natural Product Research published new progress about Natural products. 140-11-4 belongs to class esters-buliding-blocks, name is Benzyl acetate, and the molecular formula is C9H10O2, Synthetic Route of 140-11-4.

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