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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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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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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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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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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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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 high-capacity LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 cathode by transition metal acetates 被引量:3
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作者 肖政伟 张英杰 王一帆 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1568-1574,共7页
LiNi0.8Co0.1Mn0.1O2 cathode was synthesized using transition metal acetates under different synthesis conditions. Simultaneous thermogravimetric–differential scanning calorimetry–derivative thermogravimetric analysi... LiNi0.8Co0.1Mn0.1O2 cathode was synthesized using transition metal acetates under different synthesis conditions. Simultaneous thermogravimetric–differential scanning calorimetry–derivative thermogravimetric analysis was applied to investigating the mixture of transition metal acetates. X-ray powder diffraction and charge–discharge test were adopted to characterize the as-prepared LiNi0.8Co0.1Mn0.1O2. The mixture of transition metal acetates undergoes dehydration and decomposition during heating. All the examined LiNi0.8Co0.1Mn0.1O2 samples have a layered structure with R3 m space group. LiNi0.8Co0.1Mn0.1O2 samples prepared with different lithium sources under different synthesis conditions exhibit very different charge–discharge performances. The sample synthesized via the procedure of sintering at 800 °C after heating lithium carbonate and transition metal acetates at 550 °C achieves a highest capacity of 200.8 m A·h/g and an average capacity of 188.1 mA ·h/g in the first 20 cycles at 0.2C. 展开更多
关键词 Ni-rich cathode material transition metal acetate lithium source synthesis procedure
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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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Glatiramer acetate治疗多发性硬化作用机制的研究进展(综述) 被引量:3
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作者 马存根 岳炫烨 +1 位作者 Helen Tremlette Joel Oger 《中国神经免疫学和神经病学杂志》 CAS 2005年第5期269-272,共4页
Glatiramer acetate(GA)是一种人工新合成的肽类制剂,由4种氨基酸组成。实验研究表明它对多发性硬化(multiple sclerosis,MS)及其动物模型即实验性自身免疫性脑脊髓炎(experimental autoimmune encephalo-myelitis,EAE)均有防治作用。... Glatiramer acetate(GA)是一种人工新合成的肽类制剂,由4种氨基酸组成。实验研究表明它对多发性硬化(multiple sclerosis,MS)及其动物模型即实验性自身免疫性脑脊髓炎(experimental autoimmune encephalo-myelitis,EAE)均有防治作用。试验表明,GA可成为治疗MS尤其是复发-缓解型MS(relapsing-remitting MS,RRMS)的一线药。人们对其作用机制也开始逐步认识。此文就GA治疗MS的作用机制作一综述。 展开更多
关键词 glatiramer acetate 多发性硬化 作用机制
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^(11)C-Acetate与^(18)FDG PET联合显像在肝脏肿瘤诊断中的作用 被引量:15
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作者 霍力 周前 +3 位作者 党永红 傅喆 卢朝辉 桑新亭 《中国肿瘤》 CAS 2007年第3期184-186,共3页
[目的]探讨11C-乙酸盐(11C-Acetate,11C-AC)与18F-去氧葡萄糖(18FDG)PET联合显像在肝脏肿瘤诊断中的作用。[方法]20例疑肝肿瘤患者行18FDG和11C-ACPET联合显像。16例经病理证实并进行分级,4例为随访结果。[结果]3例良性病变对两种显像... [目的]探讨11C-乙酸盐(11C-Acetate,11C-AC)与18F-去氧葡萄糖(18FDG)PET联合显像在肝脏肿瘤诊断中的作用。[方法]20例疑肝肿瘤患者行18FDG和11C-ACPET联合显像。16例经病理证实并进行分级,4例为随访结果。[结果]3例良性病变对两种显像剂均无明显摄取。癌前病变2例,早期及延迟11C-AC显像均为“+”,18FDG呈“-”。肝细胞肝癌患者10例中,高分化2例仅11C-AC呈“+”,低分化2例仅18FDG“+”,6例两种显像均为“+”。3例肝腺癌、1例血管肉瘤及1例转移癌对18FDG均有明显摄取,但11C-AC均为“-”。[结论]18FDG与11C-AC联合显像可以提高肝癌诊断的阳性率以及估测肿瘤的恶性程度。 展开更多
关键词 肝肿瘤 ^11C-乙酸盐 ^18F-去氧葡萄糖 正电子发射断层显像
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诊断成人生长激素缺乏症新药-macimorelin acetate研究进展
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作者 李艳娇 李苗 张四喜 《实用药物与临床》 CAS 2019年第1期89-92,共4页
成人生长激素缺乏症(Adult growth hormone deficiency,AGHD)是一种通常由于肿瘤、手术、放疗或区域的创伤引起脑垂体或下丘脑受损导致生长激素缺乏或继发于儿童期生长激素缺乏的病症。目前,一般临床确诊AGHD均采用生长激素(Growth horm... 成人生长激素缺乏症(Adult growth hormone deficiency,AGHD)是一种通常由于肿瘤、手术、放疗或区域的创伤引起脑垂体或下丘脑受损导致生长激素缺乏或继发于儿童期生长激素缺乏的病症。目前,一般临床确诊AGHD均采用生长激素(Growth hormone,GH)兴奋试验,但由于其给药方式为静脉注射,加之存在禁忌证及不良反应,使其临床使用受限。macimorelin acetate作为一种新型口服活性生长激素释放肽受体激动剂,在AGHD诊断中使用方便、分辨率高、重复性好,且不良反应少,已被美国FDA批准用于成人生长激素缺乏症的诊断。本文对该药的作用机制、药动学、药效学、不良反应等方面进行综述。 展开更多
关键词 Macimorelin acetate AGHD 药动学 药效学
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Determination of Isotherm for Acetate and Formate Adsorption at Pt(111) Electrode by Fast Scan Voltammetry
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作者 徐杰 林楚红 +3 位作者 梅东 张尊彪 袁道福 陈艳霞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第2期191-197,I0004,共8页
Fast scan voltammetry is an efficient tool to distinguish oxidative/reductive adsorp- tion/desorption from that for bulk reaction. In this work, we provide a methodology that the isotherm of oxidative/reductive adsorp... Fast scan voltammetry is an efficient tool to distinguish oxidative/reductive adsorp- tion/desorption from that for bulk reaction. In this work, we provide a methodology that the isotherm of oxidative/reductive adsorption desorption processes at electrode surface can be obtained using just one solution with relatively low reactant concentration, by taking the advantage of varying the potential scan rate (relative of the diffusion rate) to tune the adsorption rate and proper mathematic treatment. The methodology is demonstrated by taking acetate adsorption at Pt(lll) in acidic solution as an example. The possibility for extension of this method toward mechanistic studies of complicated electrocatalytic reactions is also given. 展开更多
关键词 ADSORPTION Desorption Pt(lll) acetate anion Formate anion
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Nutrient Release Characteristics of Vinyl Chloride-Vinyl acetate Copolymers Coated SlowRelease Nitrogen Fertilizer and Its Effect on Soil Mineral Nitrogen
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作者 马洪波 许仙菊 +3 位作者 宁运旺 汪吉东 张辉 张永春 《Agricultural Science & Technology》 CAS 2014年第3期412-416,421,共6页
[Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetat... [Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetate copolymer and hydroxyl-modi- fied VCNAc were taken as coating materials to prepare slow release fertilizer. Nutri- ent release characteristics of VC/VAc slow release fertilizer was evaluated by water immersion method and the effects of VC/VAc slow release fertilizer on mineral ni- trogen were researched by pot experiment. [Result] The release periods of VC-VAc controlled-release urea and hydroxyl-modified VC/VAc coated urea were 60 and 50 d, respectively. Furthermore, the content of ammonium nitrogen reached the peak on the 30th d and the content of nitrate nitrogen reached the peak on the 60th d in soils in treatments with VCNAc and hydroxyl-modified VC/VAc; the content of nitrate nitrogen rose again on the 120th d in the treatment with VC/VAc. In terms of wheat yield, different treatments showed insignificant differences and rice yield in the treatment with VCNAc was significantly higher than that in the treatment with hy- droxyl-modified VCNAc (P〈0.05). [Conclusion] The release days of slow controlled- release fertilizer vary upon pot experiment method and water immersion method. Slow controlled-release fertilizer is not suitable for monoculture, due to long fertilizer efficiency, but multiple cropping would be optimal for its role to be fully exploited. 展开更多
关键词 Water immersion method Pot experiment method Vinyl chloride-vinyl acetate copolymer Nutrient release characteristics Soil mineral nitrogen
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人树突状细胞的成熟状态体外对Glatiramer acetate特异的T细胞系的调控作用(英文)
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作者 曹孟德 Alessandra Sanna 肖保国 《中国实验血液学杂志》 CAS CSCD 2003年第4期409-415,共7页
为了了解树突状细胞 (DC)成熟状态对Glatirameracetate(GA)特异的T细胞分化的影响 ,在体外条件下 ,分析了从多发性硬化症 (MS)病人外周血单个核细胞诱导的成熟与未成熟的树突状细胞对来自多发性硬化症病人的GA特异的T细胞系增殖及细胞... 为了了解树突状细胞 (DC)成熟状态对Glatirameracetate(GA)特异的T细胞分化的影响 ,在体外条件下 ,分析了从多发性硬化症 (MS)病人外周血单个核细胞诱导的成熟与未成熟的树突状细胞对来自多发性硬化症病人的GA特异的T细胞系增殖及细胞因子产生的影响。结果显示 ,体外条件下 ,从MS病人外周血的单个核细胞易于诱导GA抗原特异的T细胞系 (TCL) ;5 μg/ml的脂多糖 (LPS)在 2 4小时内可有效诱导DC的成熟。同未成熟的DC相比 ,成熟的DC更能有效地刺激GA抗原特异的TCL的增殖 ;GA抗原特异的TCL产生高水平的IL 2 ,IL 4 ,IFN γ ,IL 10及低水平的IL 6 ;成熟DC能促进GA抗原特异的TCL的IL 6和IL 10的分泌 ,但下调IL 2 ,IL 4及IFN γ的产生。结论 :DC的成熟状态调控TCL的增殖及细胞因子的产生。 展开更多
关键词 多发性硬化症 树突状细胞 Glatiramer acetate特异的T细胞系
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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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