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Ethyl acetate fraction of Sargassum pallidum extract attenuates particulate matter-induced oxidative stress and inflammation in keratinocytes and zebrafish 被引量:1
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作者 Wook Chul Kim Ji-Won Park +3 位作者 Bohyun Yun WonWoo Lee Kyung-Min Choi Seung-Hong Lee 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第4期137-146,共10页
Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCa... Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCaT cells and zebrafish were used to evaluate the protective effects of the ethyl acetate fraction of Sargassum pallidum extract against PM-induced oxidative stress and inflammation.The production of nitric oxide(NO),intracellular ROS,prostaglandin E_(2)(PGE_(2)),and pro-inflammatory cytokines,and the expression levels of COX-2,iNOS,and NF-κB were evaluated in PM-induced HaCaT cells.Furthermore,the levels of ROS,NO,and lipid peroxidation were assessed in the PM-exposed zebrafish model.Results:The ethyl acetate fraction of Sargassum pallidum extract significantly decreased the production of NO,intracellular ROS,and PGE_(2) in PM-induced HaCaT cells.In addition,the fraction markedly suppressed the levels of pro-inflammatory cytokines and inhibited the expression levels of COX-2,iNOS,and NF-κB.Furthermore,it displayed remarkable protective effects against PM-induced inflammatory response and oxidative stress,represented by the reduction of NO,ROS,and lipid peroxidation in zebrafish.Conclusions:The ethyl acetate fraction of Sargassum pallidum extract exhibits a protective effect against PM-induced oxidative stress and inflammation both in vitro and in vivo and has the potential as a candidate for the development of pharmaceutical and cosmeceutical products. 展开更多
关键词 Particulate matter INFLAMMATION Oxidative stress Sargassum pallidum ethyl acetate fraction ZEBRAFISH
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Tailoring Ni based catalysts by indium for the dehydrogenative coupling of ethanol into ethyl acetate
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作者 Ming Yin Jifeng Pang +4 位作者 Jin Guo Xianquan Li Yujia Zhao Pengfei Wu Mingyuan Zheng 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1321-1331,共11页
Exploring stable and robust catalysts to replace the current toxic CuCr based catalysts for dehydrogenative coupling of ethanol to ethyl acetate is a challenging but promising task.Herein,novel NiIn based catalysts we... Exploring stable and robust catalysts to replace the current toxic CuCr based catalysts for dehydrogenative coupling of ethanol to ethyl acetate is a challenging but promising task.Herein,novel NiIn based catalysts were developed by tailoring Ni catalysts with Indium(In)for this reaction.Over the optimal Ni0.1Zn0.7Al0.3InOx catalyst,the ethyl acetate selectivity reached 90.1%at 46.2%ethanol conversion under the conditions of 548 K and a weight hourly space velocity of 1.9 h^(-1)in the 370 h time on stream.Moreover,the ethyl acetate productivity surpassed 1.1 g_(ethyl acetate)g_(catalyst)^(-1)h^(-1),,one of the best performance in current works.According to catalyst characterizations and conditional experiments,the active sites for dehydrogenative coupling of ethanol to ethyl acetate were proved to be Ni4In alloys.The presence of In tailored the chemical properties of Ni,and subsequently inhibited the C-C cracking and/or condensation reactions during ethanol conversions.Over Ni4In alloy sites,ethanol was dehydrogenated into acetaldehyde,and then transformed into acetyl species with the removal of H atoms.Finally,the coupling between acetyl species and surface-abundant ethoxyde species into ethyl acetate was achieved,affording a high ethyl acetate selectivity and catalyst stability. 展开更多
关键词 Dehydrogenative coupling ETHANOL ethyl acetate Nickel and indium alloys
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The effect of ethylene-vinyl acetate copolymer on the formation process of wax crystals and hydrates
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作者 Limin Wang Jinrong Duan +2 位作者 Bei Liu Zhi Li Guangjin Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期109-119,共11页
Ethylene-vinyl acetate copolymer(EVA) as a kind of effective polymeric pour point depressant has been extensively used in the pipeline transportation of crude oil to inhibit wax deposition and improve the low temperat... Ethylene-vinyl acetate copolymer(EVA) as a kind of effective polymeric pour point depressant has been extensively used in the pipeline transportation of crude oil to inhibit wax deposition and improve the low temperature fluidity of crude oil. In this work, molecular dynamics simulations were performed to investigate the effect of EVA on wax-hydrate coexistence system to evaluate the application potentiality of EVA to the flow assurance of deep-sea oil-gas-water multiphase flow system. Our simulation results reveal that wax molecules gradually stretched and stacked from random coiling to a directional and ordered crystalline state during the process of wax solidification. The strong affinity of polar vinyl acetate side chains of EVA to neighboring water molecules made the EVA molecule prefer being in a curly state,which disrupted the ordered crystallization of surrounding wax molecules and delayed the solidification rate of wax cluster. In addition, it is found that EVA cocrystallized with wax molecules to form eutectic when the wax was fully solidified. The simulation results of hydrate nucleation and growth show that the EVA molecule displayed a two-sided effect on gas adsorption of wax crystals, which was the key factor that affected the nucleation and growth of hydrates in the methane-water system. The nonpolar hydrocarbon backbone of EVA increased the diffusion rate of methane and water, allowing more methane to diffuse to the surface of wax crystals, reducing the methane concentration in aqueous solutions and inhibiting the hydrate formation. On the other hand, the nonpolar vinyl acetate chains had a repulsive effect on methane, which reduced the adsorption area of methane on the eutectic surface and decreased the adsorption threshold value of the wax crystal. The excluded methane molecules would continue dissociating in the aqueous phase and participating in the nucleation and growth process of hydrates.Therefore, the probability of hydrate formation would be increased. It was worth noting that the inhibition performance of EVA on hydrate formation mainly played a significant role in the system with small wax crystal, while its hydrate promotion effect played a dominant role in the system with lager wax crystal. In summary, EVA could significantly inhibit both of the wax and hydrate deposition for the waxgas-water multiphase system with low wax content. When the wax content in the system was high, the role of EVA was mainly played in the alleviation of wax crystallization rather than the gas hydrates. The results of the present work can contribute to a better understanding of EVA on wax deposition and hydrate formation, and provide theoretical support of the potential industrial applications of EVA. 展开更多
关键词 Wax crystallization Hydrate formation ethylene-vinyl acetate copolymer Molecular dynamics simulation
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Polyvinyl Acetate and Vinyl Acetate-Ethylene Hybrid Adhesive: Synthesis, Characterization, and Properties
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作者 Ravindra V. Gadhave 《Open Journal of Polymer Chemistry》 2024年第1期1-18,共18页
The goal is to develop a hybrid IPN network of polyvinyl acetate (PVAc) and ethylene-vinyl acetate (VAE). In this research work, the vinyl acetate (VAc)/ VAE hybrid emulsion and polyvinyl acetate emulsion (PVAc) were ... The goal is to develop a hybrid IPN network of polyvinyl acetate (PVAc) and ethylene-vinyl acetate (VAE). In this research work, the vinyl acetate (VAc)/ VAE hybrid emulsion and polyvinyl acetate emulsion (PVAc) were effectively synthesized. Emulsions with various characteristics have been developed by adjusting the weight ratios between the vinyl acetate monomer and the VAE component. The impacts on the mechanical, thermal, and physical properties of the films were investigated using tests for pencil hardness, tensile shear strength, pH, contact angle measurement, differential scanning calorimetry (DSC), and viscosity. When 5.0 weight percent VAE was added, the tensile shear strength in dry conditions decreased by 18.75% after a 24-hour bonding period, the heat resistance decreased by 26.29% (as per WATT 91) and the tensile shear strength decreased by approximately 36.52% in wet conditions (per EN 204). The pristine sample’s results were also confirmed by the contact angle test. The interpenetrating network (IPN) formation in hybrid PVAc emulsion as primary bonds does not directly attach to PVAc and VAE chains. The addition of VAE reduced the mechanical properties (at dry conditions) and heat resistance as per WATT 91. Contact angle analysis demonstrated that PVAc adhesives containing VAE had increased water resistance when compared to conventional PVA stabilised PVAc homopolymer-based adhesives. When compared to virgin PVAc Homo, the water resistance of the PVAc emulsion polymerization was enhanced by the addition of VAE. 展开更多
关键词 ethylene-Vinyl acetate Dispersion Polyvinyl acetate HYBRID WOOD ADHESIVE
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Formation mechanisms of ethyl acetate and organic acids in Kluyveromyces marxianus L1-1 in Chinese acid rice soup 被引量:1
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作者 Na Liu Likang Qin +1 位作者 Laili Hu Song Miao 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期45-56,共12页
This study aims to explore the formation mechanism of ethyl acetate and organic acids in acid rice soup(rice-acid soup)inoculated with Kluyveromyces marxianus L1-1 through the complementary analysis of transcriptome a... This study aims to explore the formation mechanism of ethyl acetate and organic acids in acid rice soup(rice-acid soup)inoculated with Kluyveromyces marxianus L1-1 through the complementary analysis of transcriptome and proteome.The quantity of K.marxianus L1-1 varied significantly in the fermentation process of rice-acid soup and the first and third days were the two key turning points in the growth phase of K.marxianus L1-1.Importantly,the concentrations of ethyl acetate,ethanol,acetic acid,and L-lactic acid increased from day 1 to day 3.At least 4231 genes and 2937 proteins were identified and 610 differentially expressed proteins were annotated to 30 Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways based on the analysis results of transcriptome and proteome.The key genes and proteins including up-regulated alcohol dehydrogenase family,alcohol O-acetyltransferase,acetyl-CoA C-acetyltransferase,acyl-coenzyme A thioester hydrolase,and down-regulated aldehyde dehydrogenase family were involved in glycolysis/gluconeogenesis pathways,starch and sucrose metabolism pathways,amino sugar and nucleotide sugar metabolism pathways,tricarboxylic acid(TCA)cycle,and pyruvate metabolism pathways,thus promoting the formation of ethyl acetate,organic acids,alcohols,and other esters.Our results revealed the formation mechanisms of ethyl acetate and organic acids in rice-acid soup inoculated with K.marxianus L1-1. 展开更多
关键词 Kluyveromyces marxianus Fermented rice soup ethyl acetate Organic acid Formation mechanism
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Investigation on catalytic distillation for ethyl acetate production with different catalytic packing structures
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作者 Zhiwei Wang Yu Zhang +3 位作者 Zhi Zhang Daowei Zhou Zhikai Cao Yong Sha 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期63-72,共10页
The catalytic packing is the core component of the catalytic distillation,and how the catalyst exists in the packing has significant influence on the process.To investigate the effect of catalyst packings on the catal... The catalytic packing is the core component of the catalytic distillation,and how the catalyst exists in the packing has significant influence on the process.To investigate the effect of catalyst packings on the catalytic distillation process,the classical ethyl acetate reactive distillation system was utilized,and a supported catalytic packing(SCP)was prepared in comparison with the conventional tea-bag catalytic packing(TBP).Laboratory scale experiments showed that the ethyl acetate conversion of the SCP was superior to the TBP at a low catalyst loading.The effects of reaction kinetics,mass transfer performance and actual catalytic efficiency of the packings on this process were regarded as reasons and studied by combining the experiments and numerical simulation.Results suggested that the relatively immediate“in-situ separation”caused by the rapid reaction kinetics and better mass transfer performance of SCP may be a main reason for the difference of the conversion. 展开更多
关键词 Catalytic packing ethyl acetate Catalytic distillation Mass transfer ESTERIFICATION Reaction kinetics
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Dietary sodium acetate and sodium butyrate improve high-carbohydrate diet utilization by regulating gut microbiota, liver lipid metabolism, oxidative stress, and inflammation in largemouth bass(Micropterus salmoides) 被引量:1
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作者 Qiao Liu Liangshun Cheng +9 位作者 Maozhu Wang Lianfeng Shen Chengxian Zhang Jin Mu Yifan Hu Yihui Yang Kuo He Haoxiao Yan Liulan Zhao Song Yang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1704-1722,共19页
Background Adequate level of carbohydrates in aquafeeds help to conserve protein and reduce cost. However, studies have indicated that high-carbohydrate(HC) diet disrupt the homeostasis of the gut–liver axis in large... Background Adequate level of carbohydrates in aquafeeds help to conserve protein and reduce cost. However, studies have indicated that high-carbohydrate(HC) diet disrupt the homeostasis of the gut–liver axis in largemouth bass, resulting in decreased intestinal acetate and butyrate level.Method Herein, we had concepted a set of feeding experiment to assess the effects of dietary sodium acetate(SA) and sodium butyrate(SB) on liver health and the intestinal microbiota in largemouth bass fed an HC diet. The experimental design comprised 5 isonitrogenous and isolipidic diets, including LC(9% starch), HC(18% starch), HCSA(18% starch;2 g/kg SA), HCSB(18% starch;2 g/kg SB), and HCSASB(18% starch;1 g/kg SA + 1 g/kg SB). Juvenile largemouth bass with an initial body weight of 7.00 ± 0.20 g were fed on these diets for 56 d.Results We found that dietary SA and SB reduced hepatic triglyceride accumulation by activating autophagy(ATG101, LC3B and TFEB), promoting lipolysis(CPT1α, HSL and AMPKα), and inhibiting adipogenesis(FAS, ACCA, SCD1 and PPARγ). In addition, SA and SB decreased oxidative stress in the liver(CAT, GPX1α and SOD1) by activating the Keap1-Nrf2 pathway. Meanwhile, SA and SB alleviated HC-induced inflammation by downregulating the expression of pro-inflammatory factors(IL-1β, COX2 and Hepcidin1) through the NF-κB pathway. Importantly, SA and SB increased the abundance of bacteria that produced acetic acid and butyrate(Clostridium_sensu_stricto_1). Combined with the KEGG analysis, the results showed that SA and SB enriched carbohydrate metabolism and amino acid metabolism pathways, thereby improving the utilization of carbohydrates. Pearson correlation analysis indicated that growth performance was closely related to hepatic lipid deposition, autophagy, antioxidant capacity, inflammation, and intestinal microbial composition.Conclusions In conclusion, dietary SA and SB can reduce hepatic lipid deposition;and alleviate oxidative stress and inflammation in largemouth bass fed on HC diet. These beneficial effects may be due to the altered composition of the gut microbiota caused by SA and SB. The improvement effects of SB were stronger than those associated with SA. 展开更多
关键词 High carbohydrate diet Intestinal microbiota Largemouth bass Lipid deposition Sodium acetate Sodium butyrate
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Regulating the Localization of Intumescent Flame Retardant for Improving the Flame Retardancy of Ethylene-vinyl Acetate Copolymer Using Polyamide 6 as a Charring Agent
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作者 高喜平 ZHAO Pan +3 位作者 YAO Dahu 陆昶 YUE Ruiheng SHENG Qi 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期701-711,共11页
Polyamide 6 (PA6) was employed as a charring agent of intumescent flame retardant (IFR) to improve the flame retardancy of ethylene-vinyl acetate copolymer (EVA). Different processing procedures were used to regulate ... Polyamide 6 (PA6) was employed as a charring agent of intumescent flame retardant (IFR) to improve the flame retardancy of ethylene-vinyl acetate copolymer (EVA). Different processing procedures were used to regulate the localization of IFR in the EVA matrix. Localizations in which IFR was dispersed in the PA6phase or in the EVA phase were prepared. The effect of the localization of IFR on the flame retardancy of EVA was investigated. The limited oxygen index (LOI), vertical burning (UL 94) and cone calorimeter test (CCT)showed that the localization of IFR in the EVA matrix exhibited a remarkable influence on the flame retardancy.Compared with EVA/IFR, a weak improvement in the flame retardancy was observed in the EVA/PA6/IFR blend withthe localization of IFR in the PA6 phase. When IFR was regulated from the PA6 phase to the EVA matrix,a remarkable increase in the flame retardancy was exhibited. The LOI was increased from 27.8%to 32.7%, and the UL 94 vertical rating was increased from V-2 to V-0. Moreover, an approximately 41.36%decrease in the peak heat release rate was exhibited. A continuous and compact intumescent charring layer that formed in the blends with the localization of IFR in the EVA matrix should be responsible for its excellent flame retardancy. 展开更多
关键词 intumescent flame retardant charring agent LOCALIZATION polyamide 6 ethylene vinyl acetate
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Novel Sustainable Cellulose Acetate Based Biosensor for Glucose Detection
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作者 M.F.Elkady E.M.El-Sayed +2 位作者 Mahmoud Samy Omneya A.Koriem H.Shokry Hassan 《Journal of Renewable Materials》 EI CAS 2024年第2期369-380,共12页
In this study,green zinc oxide(ZnO)/polypyrrole(Ppy)/cellulose acetate(CA)film has been synthesized via solvent casting.This film was used as supporting material for glucose oxidase(GOx)to sensitize a glucose biosenso... In this study,green zinc oxide(ZnO)/polypyrrole(Ppy)/cellulose acetate(CA)film has been synthesized via solvent casting.This film was used as supporting material for glucose oxidase(GOx)to sensitize a glucose biosensor.ZnO nanoparticles have been prepared via the green route using olive leaves extract as a reductant.ZnO/Ppy nanocomposite has been synthesized by a simple in-situ chemical oxidative polymerization of pyrrole(Py)monomer using ferric chloride(FeCl3)as an oxidizing agent.The produced materials and the composite films were characterized using X-ray diffraction analysis(XRD),scanning electron microscope(SEM),Fourier transform infrared(FTIR)and thermogravimetric analysis(TGA).Glucose oxidase was successfully immobilized on the surface of the prepared film and then ZnO/Ppy/CA/GOx composite was sputtered with platinum electrode for the current determination at different initial concentrations of glucose.Current measurements proved the suitability and the high sensitivity of the constructed biosensor for the detection of glucose levels in different samples.The performance of the prepared biosensor has been assessed by measuring and comparing glucose concentrations up to 800 ppm.The results affirmed the reliability of the developed biosensor towards real samples which suggests the wide-scale application of the proposed biosensor. 展开更多
关键词 Biosensors composite films GLUCOSE POLYPYRROLE green ZnO cellulose acetate
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Efficient and selective upcycling of waste polylactic acid into acetate using nickel selenide
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作者 Bing Lan Yinfang Chen +4 位作者 Nantian Xiao Na Liu Chao Juan Chuan Xia Fan Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期575-584,I0012,共11页
The conversion of waste polylactic acid(PLA)plastics into high-value-added chemicals through electrochemical methods is a promising and sustainable approach.However,developing efficient and highly selective catalysts ... The conversion of waste polylactic acid(PLA)plastics into high-value-added chemicals through electrochemical methods is a promising and sustainable approach.However,developing efficient and highly selective catalysts for lactic acid oxidation reaction(LAOR)and understanding the reaction process are challenging.Here,we report the electrooxidation of waste PLA to acetate at a high current density of 100 mA cm-2 with high Faraday efficiency(~95%)and excellent stability(>100 h)over a nickel selenide nanosheet catalyst.In addition,a total Faraday efficiency of up to 190%was achieved for carboxylic acids,including acetic acid and formic acid,by coupling with the cathodic CO_(2) reduction reaction.In situ experimental results and theoretical simulations revealed that the catalytic activity center of LAOR was dynamically formed NiOOH species,and the surface-adsorbed SeO_(x) species accelerated the formation of Ni~(3+)species,thus promoting catalytic activity.The mechanism of lactic acid electrooxidation was further elucidated.Lactic acid was dehydrogenated to produce pyruvate first and then formed CH_3CO due to preferential C-C bond cleavage,resulting in the presence of acetate.This work demonstrated a sustainable method for recycling waste PLA and CO_(2) into high-value-added products. 展开更多
关键词 Waste plastic upcycling Poly(lactic acid) Lactic acid electro-oxidation Acetic acid
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Tuning the product selectivity of dimethyl oxalate hydrogenation over WO_(x) modified Cu/SiO_(2) catalysts
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作者 Zheng Li Zhuo Ma +9 位作者 Yihui Li Ziang Zhao Yuan Tan Ziyin Liu Xingkun Chen Nian Lei Huigang Wang Wei Lu Hejun Zhu Yunjie Ding 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期128-138,I0004,共12页
Product selectivity and reaction pathway are highly dependent on surface structure of heterogeneous catalysts.For vapor-phase hydrogenation of dimethyl oxalate(DMO),"EG route"(DMO→methyl glycolate(MG)ethyle... Product selectivity and reaction pathway are highly dependent on surface structure of heterogeneous catalysts.For vapor-phase hydrogenation of dimethyl oxalate(DMO),"EG route"(DMO→methyl glycolate(MG)ethylene glycol(EG)→ethanol(ET))and"MA route"(DMO→MG→methyl acetate(MA))were proposed over traditional Cu based catalysts and Mo-based or Fe-based catalysts,respectively.Herein,tunable yield of ET(93.7%)and MA(72.1%)were obtained through different reaction routes over WO_(x) modified Cu/SiO_(2) catalysts,and the corresponding reaction route was further proved by kinetic study and in-situ DRIFTS technology.Mechanistic studies demonstrated that H_(2) activation ability,acid density and Cu-WO_(x) interaction on the catalysts were tuned by regulating the surface W density,which resulted in the different reaction pathway and product selectivity.What's more,high yield of MA produced from DMO hydrogenation was firstly reported with the H_(2) pressure as low as 0.5 MPa. 展开更多
关键词 ETHANOL Dimethyl oxalate Selective hydrogenation Methyl acetate WCu/SiO_(2)catalyst
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Syntheses,structures,and properties of three coordination polymers based on 5⁃ethylpyridine⁃2,3⁃dicarboxylic acid and N⁃containing ligands
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作者 TANG Long BIAN Yaxin +3 位作者 CHEN Luyuan HOU Xiangyang WANG Xiao WANG Jijiang 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第10期1975-1985,共11页
Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,... Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,phen=phenanthroline,bpe=1,2⁃bis(4⁃pyridyl)ethylene)were synthesized by solvothermal reactions and characterized by single⁃crystal X⁃ray diffraction,thermogravimetric analyses,IR spectroscopy and elemental analysis.1 displays a 1D chain struc⁃ture,and these chains are joined by O-H…O hydrogen bonding andπ⁃πstacking interactions to generate a 2D layer structure.2 displays a 2D layer structure,and adjacent layers are generated 3D architecture throughπ⁃πstacking interactions.3 displays a 1D chain structure,and adjacent chains are generated double layer structure through O-H…O hydrogen bonding.The fluorescent properties of 1 and 3 indicate that they can potentially be used as a luminescent sensor.1 was highly selective and sensitive towards o⁃nitrophenol through different detection mechanisms,however,3 was highly selective and sensitive towards 2,4,6⁃trinitrophenol.In addition,the magnetic behavior of 2 has also been investigated.CCDC:2172533,1,2355773,2,2355774,3. 展开更多
关键词 coordination polymers 5⁃ethyl⁃pyridine⁃2 3⁃dicarboxylate ligand crystal structures fluorescent properties magnetic behavior
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Megestrol acetate plus metformin for fertility-sparing treatment of atypical endometrial hyperplasia and early-stage endometrial adenocarcinoma: a prospective study
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作者 Yuanyuan WANG Tianjiao LAI +4 位作者 Danxia CHU Jing BAI Shuping YAN Haixia QIN Ruixia GUO 《南方医科大学学报》 CAS CSCD 北大核心 2024年第11期2055-2062,共8页
Objective To evaluate the efficacy of medroxyprogesterone acetate(MA)plus metformin as the primary fertility-sparing treatment for atypical endometrial hyperplasia(AEH)and early-stage grade 1 endometrial adenocarcinom... Objective To evaluate the efficacy of medroxyprogesterone acetate(MA)plus metformin as the primary fertility-sparing treatment for atypical endometrial hyperplasia(AEH)and early-stage grade 1 endometrial adenocarcinoma(G1 EAC)and the recurrence rate after treatment.Methods Sixty patients(aged 20-42 years)with AEH and/or grade 1 EAC limited to the endometrium were enrolled prospectively and randomized into two groups(n=30)to receive oral MA treatment at the daily dose of 160 mg(control)or MA plus oral metformin(850 mg,twice a day)for at least 6 months.The treatment could extend to 12 months until a complete response(CR)was achieved,and follow-up hysteroscopy and curettage were performed every 3 months.For all the patients who achieved CR,endometrial expressions of IGFBP-rP1,p-Akt and p-AMPK were detected immunohistochemically.Results A total of 58 patients completed the treatment.After 9 months of treatment,23(76.7%)patients in the combined treatment group and 20(71.4%)in the control group achieved CR;two patients in the control group achieved CR after converting to the combined treatment.The recurrence rate did not differ significantly between the control group and combined treatment group(30.0%vs 22.7%,P>0.05).Ten(35.7%)patients in the control group experienced significant weight gain of 5.7±6.1 kg,while none of the patients receiving the combined treatment exhibited significant body weight changes.Compared with the control group,the patients receiving the combined treatment showed enhanced endometrial expressions of IGFBP-rP1 and p-AMPK with lowered p-Akt expression.Conclusion Metformin combined with MA may provide an effective option for fertility-sparing treatment of AEH and grade 1 stage IA EAC,and the clinical benefits of metformin for controlling MA-induced weight gain and promoting endometrial expressions of IGFBP-rP1 and p-AMPK while inhibiting p-Akt expression warrants further study. 展开更多
关键词 endormetrial adenocarcinoma METFORMIN atypical endometrial hyperplasia fertility-sparing treatment megestrol acetate insulin-like growth factor binding protein-related protein 1
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Research Progress of Environment Friendly Plasticizers for Cellulose Acetate Processing
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作者 Rui Ding Mengyou Li 《Expert Review of Chinese Chemical》 2024年第2期32-36,共5页
Cellulose acetate(CA)is an important cellulose derivative that can undergo thermoplas-tic processing.Plasticizers can form stable hydrogen bonds with CA molecular chains,reducing intermolecular and intramolecular inte... Cellulose acetate(CA)is an important cellulose derivative that can undergo thermoplas-tic processing.Plasticizers can form stable hydrogen bonds with CA molecular chains,reducing intermolecular and intramolecular interactions,and play an important role in the melting processing of CA.In recent years,environmentally friendly plasticizers that are natural,non-toxic,odorless,low dissolution,and low migration have received increas-ing attention in plastic processing.This article reviews the research progress of environ-mentally friendly plasticizers such as natural plasticizers,ionic liquid plasticizers,citrate plasticizers,and polyethylene glycol plasticizers in the processing of cellulose acetate,and looks forward to the application prospects of environmentally friendly plasticizers. 展开更多
关键词 cellulose acetate environment protection plasticizers
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A Review of Abiraterone Acetate for the Treatment of Metastatic Castration-Resistant Prostate Cancer
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作者 Lin Ma 《Journal of Clinical and Nursing Research》 2024年第6期311-315,共5页
Prostate cancer is a common malignant tumor of the urinary system in men,and the incidence and detection rate of prostate cancer have been rising significantly in recent years.Androgens play an important role in the o... Prostate cancer is a common malignant tumor of the urinary system in men,and the incidence and detection rate of prostate cancer have been rising significantly in recent years.Androgens play an important role in the occurrence and development of prostate cancer,so hormone deprivation therapy has become an essential means of prostate cancer treatment.Abiraterone acetate is a therapeutic agent for prostate cancer by inhibiting the enzyme activity of CYP17,thereby blocking androgen biosynthesis.In this paper,we present a review of the current mechanism of action of abiraterone acetate for prostate cancer treatment,research progress,and its side effects and limitations.It is expected to provide help for further research on the treatment of prostate cancer. 展开更多
关键词 Abiraterone acetate Prostate cancer INDICATIONS Treatment program
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Synthesis of Methyl Acetate by Dimethyl Ether Carbonylation over Cu/HMOR: Effect of Catalyst Preparation Method 被引量:4
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作者 张雪 李宇萍 +5 位作者 仇松柏 王铁军 定明月 张琦 马隆龙 于玉肖 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第1期77-82,I0004,共7页
Dimethyl ether carbonylation to methyl acetate was comparatively investigated over mor- denite supported copper (Cu/HMOR) catalysts prepared by different methods including evaporation, urea hydrolysis, incipient wet... Dimethyl ether carbonylation to methyl acetate was comparatively investigated over mor- denite supported copper (Cu/HMOR) catalysts prepared by different methods including evaporation, urea hydrolysis, incipient wetness impregnation and ion-exchange. The results showed that Cu/HMOR prepared via iron-exchange method exhibited the highest catalytic activity due to the synergistic effect of active-site metal and acidic molecular sieve support. Conversion of 95.3% and methyl acetate selectivity of 94.9% were achieved under conditions of 210℃, 1.5 MPa, and GSHV of 4883 h-1. The catalysts were characterized by nitrogen absorption, X-ray diffraction, NH3 temperature program desorption, and CO temperature program desorption techniques. It was found that Cu/HMOR prepared by ion-exchange method possessed high surface area, moderate strong acid centers, and CO adsorption centers, which improved catalytic performance for the reaction of CO insertion to dimethyl ether. 展开更多
关键词 Biomass energy Methyl acetate Dimethyl ether CARBONYLATION HMOR cat-alyst
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SYNTHESIS OF 3,7-DIMETHYL-2-TRIDECANYL ACETATE--Active Component of Sex Pheromone of Pine Sawfly Diprion pini 被引量:2
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作者 孟祎 陈立功 +2 位作者 许艳杰 古险峰 宋芸 《Transactions of Tianjin University》 EI CAS 2001年第4期282-285,共4页
The total synthesis of 3,7 dimethyl 2 tridecanyl acetate,the active component of the sex pheromone of diprion pini,was investigated in this paper.The two key synthins blocks,2 methyl octan 1 yl lithium and 3,4 ... The total synthesis of 3,7 dimethyl 2 tridecanyl acetate,the active component of the sex pheromone of diprion pini,was investigated in this paper.The two key synthins blocks,2 methyl octan 1 yl lithium and 3,4 dimethyl γ butyrolactone,were obtained from diethyl malonate and 2,3 epoxybutane.2 Methyl octan 1 yl lithium reacted with 3,4 dimethyl γ butyrolactone to yield the ketoalcohol and then followed by Huang Minlong reduction to afford 3,7 dimethyl 2 tridecanol,acylated with acetic anhydide to give 3,7 dimethyl 2 tridecanyl acetate. 展开更多
关键词 pine sawfly sex pheromone 3 7 dimethyl 2 tridecanol 3 7 dimethyl 2 tridecanyl acetate
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A Study of Heteropoly Complexes of Rare Earths as Catalyst Promoter in the Synthesis of Ethyl Acetate
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作者 Shui Yang HE Ke PENG +3 位作者 Di ZHANG Wang Ting WU Gang Lin XUE Qi Zhen SHI 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第9期1095-1097,共3页
The capability of the synthesized heteropoly complexes of rare earths {K10 [(O39W11Si) Ln(Gly)3Ln(SiW11O39)]?H2O (Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy)} as the catalyst promoter in the synthesis of the ethyl acetate was ... The capability of the synthesized heteropoly complexes of rare earths {K10 [(O39W11Si) Ln(Gly)3Ln(SiW11O39)]?H2O (Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy)} as the catalyst promoter in the synthesis of the ethyl acetate was studied. The results showed that the quantity of H2SO4 used for synthesizing the ethyl acetate can be reduced by 75% and the yield reached 98% at the optional condition. 展开更多
关键词 Heteropoly complexes of rare earths catalyst promoter ethyl acetate.
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Synthesis of ethyl acetate by esterification of acetic acid with ethanol over a heteropolyacid on montmorillonite K10 被引量:7
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作者 Hanumant Gurav Vijay V.Bokade 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第2期161-164,共4页
In present work,liquid phase esterification of acetic acid with ethanol over dodecatungestophosphoric acid (DTPA) supported on K10 montmorillonite was systematically studied and optimization of process parameters wa... In present work,liquid phase esterification of acetic acid with ethanol over dodecatungestophosphoric acid (DTPA) supported on K10 montmorillonite was systematically studied and optimization of process parameters was carried out.The 20% m/m DTPA/K10 was found to be the optimum catalyst with 90% acetic acid conversion and 100% ethyl acetate selectivity.The study was also explored to see the feasibility of 20% m/m DTPA/K10 as a catalyst for the alkylation of acetic acid with other alcohols like methanol,iso-propanol and n-butanol.The 20% m/m DTPA/K10 has shown increased activity with the increase in carbon number,at the same alcohol reflux.The results are novel. 展开更多
关键词 acetic acid ETHANOL HETEROPOLYACID montmorillonite K10 ethyl acetate
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Comparison of continuous homogenous azeotropic and pressure-swing distillation for a minimum azeotropic system ethyl acetate/nhexane separation 被引量:6
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作者 Liping Lü Lin Zhu +2 位作者 Huimin Liu Hang Li Shirui Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第10期2023-2033,共11页
Continuous homogenous azeotropic distillation(CHAD) and pressure-swing distillation(PSD) are explored to separate a minimum-boiling azeotropic system of ethyl acetate and n-hexane. The CHAD process with acetone as the... Continuous homogenous azeotropic distillation(CHAD) and pressure-swing distillation(PSD) are explored to separate a minimum-boiling azeotropic system of ethyl acetate and n-hexane. The CHAD process with acetone as the entrainer and the PSD process with the pressures of 0.1 MPa and 0.6 MPa in two columns are designed and simulated by Aspen Plus. The operating conditions of the two processes are optimized via a sequential modular approach to obtain the minimum total annual cost(TAC). The computational results show that the partially heat integrated pressure-swing distillation(HIPSD) has reduced in the energy cost and TAC by 40.79% and 35.94%, respectively, than the conventional PSD, and has more greatly reduced the energy cost and TAC by 62.61% and 49.26% respectively compared with the CHAD process. The comparison of CHAD process and partially HIPSD process illustrates that the partially HIPSD has more advantages in averting the product pollution, energy saving, and economy. 展开更多
关键词 Continuous homogenous azeotropic distillation Pressure-swing distillation ethyl acetate/n-hexane Azeotrope
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