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合成(E)-2,3-二卤-2-丁烯-1,4-二醇及其衍生物的新方法
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作者 李金恒 李国平 +1 位作者 江焕峰 陈鸣才 《广州化学》 CAS 2001年第3期15-17,22,共4页
采用乙醇 /苯为反应溶剂 ,以α -炔醇为反应原料 ,氯化铜为卤化剂 ,立体专一性合成 (E) - 2 ,3-二卤 - 2 -丁烯 - 1 ,4-二醇及其衍生物。分离产率为 1 0 0 % ,粗产品纯度即可达 98% (GC)
关键词 乙醇/苯 卤化 α-炔醇 合成 氯化铜 (E)-2 3-二卤-2-丁烯-1 4-二醇 衍生物
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Phenylethanoid Glycosides from Cultivated Cistanche salsa 被引量:7
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作者 杨建华 堵年生 热娜.卡斯木 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第4期242-245,共4页
Introduction The plants of genus Cistanche G. Beck, which belong to Orobanchaceae family, include about twenty species, and there are four species and one variety are distributed in the northwest part of China. The d... Introduction The plants of genus Cistanche G. Beck, which belong to Orobanchaceae family, include about twenty species, and there are four species and one variety are distributed in the northwest part of China. The dried fleshy stem of Cistanche genus plant known as 'Roucongrong' in Chinese traditional medicine, has long been used for kidney deficiency, female infertility, morbid leucorrhea, and neurasthenia. Studies on active components and pharmacological activities show that it possesses significant activities in enhancing potency, anti-fatigue, immuno-modulability, etc, and phenylethanoid glycosides are the major active components. Due to excessive exploitation, its natural resources are facing with exhaustion. In order to improve this situation, the plant has been cultivated on a large scale in the northwest part of China. Up to now, the chemical investigations of the cultivated Cistartcbe salsa have not been undertaken. In this paper we report seven phenylethanoid glycosides from the cultivated Cistanche salsa: echinacoside (1), cistanoside A (2), acteoside (3), isoacteoside (4), 2'-acetylacteoside (5), tubuloside B (6), and eutigoside A (7). Among them, compound 7 isolated fronl family Orobanchaceae was reported previously, and compounds 1, 2, 3, 4, 5 and 6 from the cultivated Cistanche salsa are reported for the first time. 展开更多
关键词 CISTANCHE Cistanche salsa (C.A.Mey.) G.Beck phenylethanoid glycosides the cultivated
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丙烯酸-2,4,6-三硝基苯乙酯的合成及热分解 被引量:2
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作者 刘强强 金波 +3 位作者 彭汝芳 舒远杰 楚士晋 董海山 《含能材料》 EI CAS CSCD 北大核心 2012年第5期579-582,共4页
以TNT、甲醛为原料,在弱碱性条件下反应合成得到2,4,6-三硝基苯乙醇(PicCH2CH2OH);PicCH2CH2OH在浓硫酸催化下和丙烯酸在甲苯中回流反应24h,合成得到丙烯酸-2,4,6-三硝基苯乙酯,产率为62%。采用紫外可见光谱(UV-Vis)、核磁共振氢谱(1HN... 以TNT、甲醛为原料,在弱碱性条件下反应合成得到2,4,6-三硝基苯乙醇(PicCH2CH2OH);PicCH2CH2OH在浓硫酸催化下和丙烯酸在甲苯中回流反应24h,合成得到丙烯酸-2,4,6-三硝基苯乙酯,产率为62%。采用紫外可见光谱(UV-Vis)、核磁共振氢谱(1HNMR)、红外光谱(FTIR)、质谱(MS)以及元素分析等对产物结构进行了表征。利用热重分析(TG)对产物热稳定性进行了研究,采用Kissinger方法和Ozawa方法计算其热分解活化能Ea分别为99.78,102.96kJ·mol-1。 展开更多
关键词 有机化学 2 4 6-三硝基乙醇 丙烯酸-2 4 6-三硝基乙酯 热稳定性 活化能
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Enantio-selective preparation of (S)-1-phenylethanol by a novel marine GDSL lipase MT6 with reverse stereo-selectivity 被引量:4
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作者 邓盾 张云 +1 位作者 孙爱君 胡云峰 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第11期1966-1974,共9页
We previously functionally characterized a novel marine microbial GDSL lipase MT6 and identified that the stereo-selectivity of MT6 was opposite to that of other common lipases in trans-esterification reactions.Herein... We previously functionally characterized a novel marine microbial GDSL lipase MT6 and identified that the stereo-selectivity of MT6 was opposite to that of other common lipases in trans-esterification reactions.Herein,we have investigated the use of MT6 in stereo-selective biocatalysis through direct hydrolysis reactions.Notably,the stereo-selectivity of MT6 was also demonstrated to be opposite to that of other common lipases in hydrolysis reactions.Parameters,including temperature,organic co-solvents,pH,ionic strength,catalyst loading,substrate concentration,and reaction time,affecting the enzymatic resolution of racemic 1-phenylethyl acetate were further investigated,with the e.e.of the final(S)-l-Phenylethanol product and the conversion being 97%and 28.5%,respectively,after process optimization.The lengths of side chains of 1-phenylethyl esters greatly affected the stereo-selectivity and conversion during kinetic resolutions.MT6 is a novel marine microbial GDSL lipase exhibiting opposite stereo-selectivities than other common lipases in both trans-esterification reactions and hydrolysis reactions. 展开更多
关键词 GDSLlipase BIOCATALYSIS Kinetic resolution Direct hydrolysis (S)-1-Phenylethanol Reverse stereo-selectivity
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A New Phenylethanoid Glucoside from Buddleia officinalis 被引量:1
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作者 李教社 赵玉英 马立斌 《Journal of Chinese Pharmaceutical Sciences》 CAS 1997年第4期6-9,共4页
A new phenylethanoid glycoside, neobudofficide B was isolated from Buddleia officinalis. On the basis of spectral and chemical evidence, the glycoside was identified as β ( 3′, 4′ dihydroxy, 6′ N pyridinechlo... A new phenylethanoid glycoside, neobudofficide B was isolated from Buddleia officinalis. On the basis of spectral and chemical evidence, the glycoside was identified as β ( 3′, 4′ dihydroxy, 6′ N pyridinechloride phenyl ) ethyl O α L rhamnopyranosyl ( 1→3 ) β D ( 4″ O caffeoyl ) glucopyranoside. 展开更多
关键词 Buddleia officinalis Phenylethenoid glycoside Neobudofficide B
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IN-SITU POLYMERIZED SYNTHESIS AND PROPERTIES OF NANO-ZnO/PEG/PET COMPOSITE
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作者 董祥 陶杰 汪涛 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第4期303-310,共8页
Nano-ZnO particle (nZnOp) reinforced polyethylene glycol (PEG)/polyethylene terephthalate (PET) (nZnOp/PEG/PET) copolymeric composites with different mass fractions and molecular weights of PEG are synthesized... Nano-ZnO particle (nZnOp) reinforced polyethylene glycol (PEG)/polyethylene terephthalate (PET) (nZnOp/PEG/PET) copolymeric composites with different mass fractions and molecular weights of PEG are synthesized via in-situ polymerization. The dispersion of nZnOp in copolymer matrixes and the effects of PEG and nZnOp particles on the crystallization behavior of the composites are studied by TEM, differential scanning calorimetry(DSC), XRD and Fourier thansform infrared spectroscopy (FTIR ). The results reveal that nZnOp particles are dispersed in the matrixes with nano-scale, and the addition of PEG induces more homogeneous dispersion of nZnOp. Simultaneously, these nanoparticles become nucleating centers during the crystallization of the matrixes. PEG segments can improve the flexibility of the PET molecular chain, resulting in the drop of the cold crystallization temperature and the rise of the crystallization rate of the composites. Furthermore, PEG (4 000) with the mass fraction of 10% can promote the crystallization rate of the composites. The mechanical properties show that the nano-particles strengthen and toughen the PET matrix, whereas PEG weakens these improve- ments. 展开更多
关键词 polyethylene terephthalate (PET) polyethylene glycol (PEG) NANO-COMPOSITES nano zinc oxide (ZnO)
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Enantioselective extraction of mandelic acid enantiomers based on chiral ligand exchange 被引量:1
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作者 唐课文 黄可龙 《Journal of Central South University of Technology》 2005年第2期123-128,共6页
Based on the chiral ligand exchange, the distribution behavior of mandelic acid enantiomers, and the partition of Cu2+ at different pH values were studied in a water/alcohol two-phase system containing Cu2+ and N-n-(... Based on the chiral ligand exchange, the distribution behavior of mandelic acid enantiomers, and the partition of Cu2+ at different pH values were studied in a water/alcohol two-phase system containing Cu2+ and N-n-(dodecyl-L-proline(A).) The influences of the solvent sort, the pH value, the concentrations of Cu2+ and chiral ligand on the partition coefficient(K) and separation factor(α) were discussed. The experimental results show that the A formed has more stable ternary complex with D-mandelic acid enantiomer than with L-mandelic acid enantiomer. There is an important influence of the pH value on K and α. When the pH values are less than 3.5, the formation of binary complexes is thermodynamically unfavourable. K and α become maximum when pH values are above 3.5 and the molar ratio of the chiral ligand to Cu2+ is 2∶1. 展开更多
关键词 ligand exchange EXTRACTION chiral separation mandelic acid enantiomers
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Measurement and Correlation of Solubility of Carbon Monoxide in Phenol+Ethanol Solvents 被引量:1
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作者 宣爱国 吴元欣 +2 位作者 马沛生 孙炜 沈喜珊 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第5期762-765,共4页
The solubility of carbon monoxide in phenol+ethanol mixed solvents at elevated pressures is reported in this article. The experimental results revealed the influence of pressure on the solubility of CO in phenol+eth... The solubility of carbon monoxide in phenol+ethanol mixed solvents at elevated pressures is reported in this article. The experimental results revealed the influence of pressure on the solubility of CO in phenol+ethanol mixtures. These mixtures are a poorer solvent for carbon monoxide. The solubility of CO is a linear function of pressure, and the extended Henry's constants were presented at different concentrations of phenol. The cubic Soave-Redlich-Kwong equation of state was used to correlate the experimental gas liquid equilibrium data and to predict the solubility of CO. At the same time, the binary interaction parameters, kO, for CO-phenol, CO-ethanol and phenol-ethanol systems were estimated by fitting experimental GLE data at 303.15 K and at 2.0-9.0 MPa. Hence, a model was suggested for the solubility of CO in phenol+ethanol mixed solvents. The agreement between experimental and calculated solubilities with the proposed model was rather satisfactory. 展开更多
关键词 solubility gas-liquid equilibnum carbon monoxide phenol ethanol
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Isobaric vapor–liquid equilibrium for ternary system of ethanol, ethyl propionate and para-xylene at 101.3 kPa 被引量:2
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作者 Zhongpeng Xing Yujie Gao +3 位作者 Hui Ding Xianqin Wang Lujun Li Hang Zhou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第3期560-565,共6页
Isobaric vapor–liquid equilibrium(VLE) data for the binary system ethyl propionate(2) + para-xylene(3) and ternary system ethanol(1) + ethyl propionate(2) + para-xylene(2) at atmospheric pressure(101.3 k Pa)were obta... Isobaric vapor–liquid equilibrium(VLE) data for the binary system ethyl propionate(2) + para-xylene(3) and ternary system ethanol(1) + ethyl propionate(2) + para-xylene(2) at atmospheric pressure(101.3 k Pa)were obtained by a VLE modified othmer still. All the experimental data passed a point to point consistency test of Van Ness method, which verified the data reliability. The Wilson and UNIQUAC activity coefficient models were employed to correlate the binary VLE data to obtain binary interaction parameters. Based on binary interaction parameters, ternary VLE data of ethanol(1) + ethyl propionate(2) + para-xylene(3) were predicted by Wilson and UNIQUAC models, which proved that predicted values are consistent with the experimental data.Furthermore, azeotropic phenomenon between ethanol and ethyl propionate disappears when the mole ratio of para-xylene and binary system of ethanol and ethyl propionate is 1:1. Therefore, this paper convinced that para-xylene is a proper extractive additive that could be used in extractive distillation to separate the binary azeotropic system of ethanol and ethyl propionate. 展开更多
关键词 Vapor-liquid equilibrium Azeotrope Ethanol Ethyl propionate Para-xylene
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PREPARATION AND PROPERTIES OF POLY(LACTIC ACID-CO-GLYCOL TEREPHTHALIC ACID)COPOLYESTER 被引量:1
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作者 GAO Cuili JI Quan +1 位作者 KONG Qingshan XIA Yanzhi 《Chinese Journal of Reactive Polymers》 2006年第1期63-69,共7页
To obtain a kind of biodegradable polymer material with satisfactory properties, a new biodegradable copolyester poly(lactic acid-co-glycol terephthalate) (PETA), was synthesized from three monomers of lactic acid... To obtain a kind of biodegradable polymer material with satisfactory properties, a new biodegradable copolyester poly(lactic acid-co-glycol terephthalate) (PETA), was synthesized from three monomers of lactic acid, glycol and terephthalic acid. The resulting copolyesters, PETA, were characterized by FT-IR, ^1H-NMR, DSC, TGA and by the ways of weight loss rate to characterize their biodegradability. The findings in this work indicated that, the Tins and Tas of copolyesters PETA increased with increasing contents of the terephthalic acid units. From the biodegradation tests in natural soil, boiling water, acid buffer solution and alkali buffer solution, it was shown that the biodegradability of copolyesters PETA decreased with increasing contents of the terephthalic acid units. 展开更多
关键词 Lactic acid GLYCOL Terephthalic acid COPOLYESTER Thermal properties Biodegradability.
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Biodegradation of DTP and PET Fiber by Microbe 被引量:1
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作者 张健飞 王晓春 +1 位作者 巩继贤 顾振亚 《Journal of Donghua University(English Edition)》 EI CAS 2003年第4期107-110,共4页
The degradation of diethylene glycol terephthalate (DTP) and polyethylene terephthalate (PET) fiber by microbe was studied.The degree of DTP degradation was determined by High Performance Liquid Chromatography (HPLC) ... The degradation of diethylene glycol terephthalate (DTP) and polyethylene terephthalate (PET) fiber by microbe was studied.The degree of DTP degradation was determined by High Performance Liquid Chromatography (HPLC) to be more than 90%.The products after degradation of DTP and PET fiber were various.The degradation of DTP can be described by the first-order reaction model.The degradation of PET fiber was found to be little,but surface erosion of PET fiber could be clearly seen from the SEM photographs indicating there occurred some traces of biodegradation on the PET fiber surface. 展开更多
关键词 MICROBE DEGRADATION DTP PET fiber ENVIRONMENT Degradation kinetics
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Asymmetric Bioreduction of 3,5-Bis(trifluoromethyl) Acetophenone to Its Corresponding Alcohol by Candida troplcalis 被引量:4
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作者 王普 苏会贞 +2 位作者 孙立明 何军邀 白亚萍 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期1028-1032,共5页
(S)-3,5-bistrifluoromethylphenyl ethanol is a key chiral intermediate for the synthesis of NK-1 receptor antagonists. Enantioselective synthesis of (S)-3,5-bistrifluoromethylphenyl ethanol was successfully performed i... (S)-3,5-bistrifluoromethylphenyl ethanol is a key chiral intermediate for the synthesis of NK-1 receptor antagonists. Enantioselective synthesis of (S)-3,5-bistrifluoromethylphenyl ethanol was successfully performed in high enantiomeric excess (e.e.) through asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone catalyzed by Candida tropicalis 104 cells. The influence of some key reaction parameters such as substrate concentration, co-substrate and its concentration, biomass and reaction time was examined, respectively. The results showed that these factors obviously influence the yield, but the optical purity of the prepared product remains intact. The opti-mum conditions for the preparation of (S)-3,5-bistrifluoromethylphenyl ethanol were found to be as follows: sub-strate concentration 50 mmol?L?1; 50 g·L-1 of maltose as co-substrate; wet cell concentration 300 g·L-1; reaction for 30 h. Under above optimal conditions, the maximum yield for (S)-3,5-bistrifluoromethylphenyl ethanol reached 70.3% with 100% of product e.e. 展开更多
关键词 Candida tropicalis asymmetric reduction ENANTIOSELECTIVITY 3 5-bis(trifluoromethyl) acetophenone (S)-3 5-bistrifluoromethylphenyl ethanol
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Study on Morphology and Non-isothermal Crystallization Behavior of Poly(phenylene sulfide)/Poly(ethylene-co-cyclo-hexane 1,4-dimethanol terephthalate) Blend 被引量:1
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作者 Shi Jun Chen Yanming Chen Ying 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2010年第1期61-66,共6页
A binary alloy consisting of poly(phenylene-sulfide) (PPS)/poly(ethylene terephthalate-co-l,4- cyclohexanedimethanol) (PETG) was prepared by the melt blending technology using a twin-screw extruder. The morpho... A binary alloy consisting of poly(phenylene-sulfide) (PPS)/poly(ethylene terephthalate-co-l,4- cyclohexanedimethanol) (PETG) was prepared by the melt blending technology using a twin-screw extruder. The morphology and crystallization behavior of the alloy material were investigated by means of SEM, POM and DSC. The SEM study of the alloy samples revealed that PPS and PETG comprised an incompatible system and the interface structure of two phases could be observed distinctly when the composition of the binary alloy was being changed. The POM results had revealed that incorporation of PETG into PPS could lead to formation of larger spherulite crystals in the course of PPS crystallization, but small and grainy spherulite crystals appeared with further increase in the PETG concentration. The DSC analyses revealed that addition of PETG to the alloy composition could shift the PPS crystallization temperature towards the high-temperature region. 展开更多
关键词 PETG PPS alloy MORPHOLOGY crystallization behavior
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Optical Separation of Racemic Phenyl-alanine, and Structure of Complex Consisting of R-Phenylalanine and R-Mandelic Acid
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作者 HUZi-Qiang XUDuan-Jun +2 位作者 XUYuan-Zhi WUJing-Yun CHIANGMichaelY 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第1期38-40,共3页
The racemic phenylalanine has been separated by (R)-mandelic acid through the formation of diastereomeric molecular complex. The crystal of the title chiral complex (C8H8O3 C9H11NO2, Mr = 317.33) belongs to monoclinic... The racemic phenylalanine has been separated by (R)-mandelic acid through the formation of diastereomeric molecular complex. The crystal of the title chiral complex (C8H8O3 C9H11NO2, Mr = 317.33) belongs to monoclinic, space group C2 with a = 19.391(3), b = 5.715(4), c = 15.755(3) ? b = 115.23(1), V = 1579(1) 3, Z = 4, Dc = 1.335 g/cm3, F(000) = 672, m = 0.099 mm-1, R = 0.033 and wR = 0.060 for 1278 observed reflections (I > 2s(I)). The complex consists of (R)-mandelic acid and (R)-phenylalanine in 1:1 molar ratio, and the complex molecules form layered crystal structure by self-assembly through intermolecular H-bonding between carboxyl and carboxylate of the neighboring molecules. 展开更多
关键词 optical separation crystal structure mandelic acid PHENYLALANINE
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Simultaneous Synthesis of Dimethyl Carbonate and Poly(ethylene terephthalate) Using Alkali Metals as Catalysts 被引量:2
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作者 张丹 王庆印 +3 位作者 姚洁 王越 曾毅 王公应 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第5期772-774,共3页
Dimethyl carbonate (DMC) and poly(ethylene terephthalate) was simultaneously synthesized by the transesterification of ethylene carbonate (EC) with dimethyl terephthalate (DMT) in this paper. This reaction is ... Dimethyl carbonate (DMC) and poly(ethylene terephthalate) was simultaneously synthesized by the transesterification of ethylene carbonate (EC) with dimethyl terephthalate (DMT) in this paper. This reaction is an excellent green chemical process without poisonous substance. Various alkali metals were used as the catalysts. The results showed alkali metals had catalytic activity in a certain extent. The effect of reaction condition was also studied. When the reaction was carded out under the following conditions: the reaction temperature 250℃, molar ratio of EC to DMT 3 : 1, reaction time 3h, and catalyst amount 0.004 (molar ratio to DMT), the yield of DMC was 68.9%. 展开更多
关键词 ethylene carbonate dimethyl terephthalate dimethyl carbonate poly (ethylene terephthalate) TRANSESTERIFICATION CATALYST
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Properties of Surface Cyclic Oligomers Present on Polyester Fiber
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作者 郑敏 宋心远 《Journal of Donghua University(English Edition)》 EI CAS 2003年第1期22-26,共5页
The effects of different treatments, such as dry heat,wet heat, solvent vapor and ultrasonic, on propertiesof the cyclic oligomers on the surface of polyester fiberare studied. The components of surface oligomers area... The effects of different treatments, such as dry heat,wet heat, solvent vapor and ultrasonic, on propertiesof the cyclic oligomers on the surface of polyester fiberare studied. The components of surface oligomers areanalyzed through Thin-Layer Chromatograph. Theresult shows that: all of the treatment, especially solvent vapor treatment,call significantly increase the content of surface cyclic oligomers.The content of cyclic triIner is increased more considerably than other oligomers. Moreover,the morphology and thedistribution of surface cyclic oligomers are also different from different treatments:Dry heat and wet heat cause larger polygonal solids distributed evenly on the surface of fiber;solvent vapor nlakes fiber surface exhibit irregular rodlike crystal shapes randomly;ultrasonic treatment induces some obscureand smaller deposi^on the surface of fiber. 展开更多
关键词 heat treatment solvent vapor ULTRASONIC cyclic oligomers thin—layer chromatograph
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Liquid–liquid equilibrium extraction of ethanol with mixed solvent for bioethanol concentration 被引量:2
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作者 Hiroaki Habaki Haihao Hu Ryuichi Egashira 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第2期253-258,共6页
The extraction of ethanol with the solvents of aldehydes mixed with m-xylene was studied for the bioethanol concentration process.Furfural and benzaldehyde were selected as extraction solvents,with which the solubilit... The extraction of ethanol with the solvents of aldehydes mixed with m-xylene was studied for the bioethanol concentration process.Furfural and benzaldehyde were selected as extraction solvents,with which the solubility of water is small,expecting large distribution coefficient of ethanol.The liquid–liquid two-phase region was the largest with m-xylene solvent,followed by benzaldehyde and furfural.The region of two liquid–liquid phase became larger with the mixed solvent of m-xylene and furfural than that with furfural solvent.The NRTL model was applied to the ethanol–water–furfural–m-xylene system,and the model could well express the liquid–liquid equilibrium of the system.For any solvent used in this study,the separation selectivity of ethanol relative to water decreased as the distribution coefficient of ethanol increased.The separation selectivity with m-xylene was the largest among the employed solvents,but the distribution coefficient was the smallest.The solvent mixture of furfural and m-xylene showed relatively high distribution coefficient of ethanol and separation selectivity,even in the higher mass fraction of m-xylene in the solvent phase.The ethanol extraction with a countercurrent multistage extractor by a continuous operation was simulated to evaluate the extraction performance.The ethanol content could be concentrated in the extract phase with relatively small number of extraction stages but low yield of ethanol was obtained. 展开更多
关键词 BIOETHANOL Solvent extraction NRTL model
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Effect of 2-amino-2-[2-(4-octylphenyl) ethyl] propane- 1,3-diol hydrochloride (FTY 720) on immune liver injury in mice 被引量:5
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作者 Jing-HuaHe Hui-NaZhang Zhi-BinLin 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第4期573-576,共4页
AIM: To investigate the protective effect against two immune liver injury models in mice by 2-amino-2-[2-(4-octylphenyl) ethyl] propane-l,3-diol hydrochloride and its possible mechanisms in Con A-induced liver damage.... AIM: To investigate the protective effect against two immune liver injury models in mice by 2-amino-2-[2-(4-octylphenyl) ethyl] propane-l,3-diol hydrochloride and its possible mechanisms in Con A-induced liver damage. METHODS: Liver tissue or hepatocyte injury was monitored biochemically by measuring alanine aminotransferase (sALT) and aspartate aminotransferase (sAST) activity. Hematoxylin & eosin (HE) staining was used for histopathological examination. To evaluate the role of IFN-γ and IL-4 in the liver injury, serum levels of IFN-γ and IL-4 were determined using commercially available ELISA kit at 12 h after Con A challenge. We also determined FTY 720-induced spleen cell apoptosis by flow cytometry analysis or spleen cell proliferation test. RESULTS: Different doses of FTY 720 treatment dramatically reduced circulating markers of hepatocyte injury in two kinds of immunological liver injury models. FTY 720 dramatically reduced the elevated serum IFN-γ and IL-4 levels after Con A injection. Effect of spleen cell supernatants treated with Con A or FTY 720 on hepatocytes showed that ALT activities in cultured hepatocyte supernatants in Con A treatment group increased markedly and FTY 720 could reduce this elevated ALT activities in FTY 720 treatment group. FTY 720 dose-dependently increased the percentage of apoptotic cells in T cells and inhibited splenocyte proliferation induced by Con A. CONCLUSION: Pretreatment with FTY 720 was shown to produce protective effect on the immune liver injury in mice. The possible mechanism of FTY 720 on Con A-induced liver damage is that it could inhibit lymphocyte proliferation and induce lymphocyte apoptosis, resulting in the reduction of IL-4 or IFN-γ release, and subsequently protecting liver from being damaged by Con A. 展开更多
关键词 Immune liver injury FTY 720 Apoptosis Cell proliferation
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In-situ Polymerization-modification Process and Foaming of Poly(ethylene terephthalate) 被引量:4
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作者 仲华 奚桢浩 +1 位作者 刘涛 赵玲 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第12期1410-1418,共9页
Most of traditional linear poly(ethylene terephthalate)(PET)resins of relatively low molecular mass and narrow molecular mass distribution have low melt strength at foaming temperatures,which are not enough to support... Most of traditional linear poly(ethylene terephthalate)(PET)resins of relatively low molecular mass and narrow molecular mass distribution have low melt strength at foaming temperatures,which are not enough to support and keep cells.An in-situ polymerization-modification process with esterification and polycondensation stages was performed in a 2 L batch stirred reactor using pyromellitic dianhydride(PMDA)or pentaerythritol(PENTA)as modifying monomers to obtain PETs with high melt strength.The influence of amounts of modifying monomers on the properties of modified PET was investigated.It was found that the selected modifying monomers could effectively introduce branched structures into the modified PETs and improve their melt strength.With increasing the amount of the modifying monomer,the melt strength of the modified PET increased.But when the amount of PENTA reached 0.35%or PMDA reached 0.9%,crosslinking phenomenon was observed in the modified PET.Supercritical carbon dioxide(ScCO2)was employed as physical foaming agent to evaluate the foaming ability of modified PETs.The modified PETs had good foaming properties at 14 MPa of CO2pressure with foaming temperature ranging from 265°C to 280°C.SEM micrographs demonstrated that both modified PET foams had homogeneous cellular structures,with cell diameter ranging from 35μm to 49μm for PENTA modified PETs and38μm to 57μm for PMDA modified ones.Correspondingly,the cell density had a range of 3.5×107cells·cm 3to 7×106cells·cm 3for the former and 2.8×107cells·cm 3to 5.8×106cells·cm 3for the latter. 展开更多
关键词 poly(ethylene terephthalate) in-situ polymerization-modification supercritical carbon dioxide molten-state foaming
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Heterogeneity of Adsorption Sites and Adsorption Kinetics of n-Hexane on Metal–Organic Framework MIL-101(Cr) 被引量:1
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作者 孙雪娇 苗晋朋 +2 位作者 肖静 夏启斌 赵祯霞 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第9期962-967,共6页
The heterogeneity of adsorption sites and adsorption kinetics of n-hexane on a chromium terephthalate-based metal-organic framework MIL-10^1 (Cr) were studied by gravimetric method and temperature-programmed desorpt... The heterogeneity of adsorption sites and adsorption kinetics of n-hexane on a chromium terephthalate-based metal-organic framework MIL-10^1 (Cr) were studied by gravimetric method and temperature-programmed desorption (TPD) experiments. The MIL-101 crystals were synthesized by microwave irradiation method. The ad- sorption isotherms and kinetic curves of n-hexane on the MIL-101 were measured. Desorption activation energies of n-hexane from the MIL-10^1 were estimated by TPD experiments. The resulthowed that equilibrium amount ofn-hexane adsorbed on the MIL-10^1 was up to 5.62 mmol.g- 1 at 298 K and 1.6 x10^4 Pa, much higher than that of some activated carbons, zeolltes and so on. The isotherms of n-hexane on the MIL-101 could be well fitted with Langmuir-Freundlich model. TPD spectra exhibit two types of adsorption sites on the MIL-101 with desorption activation energies of 39.41 and 86.69 kJ. mol-1. It reflects the surface energy heterogeneity on the MIL-10I frameworks for n-hexane adsorption. The diffusion coefficients of n-hexane are in the range of (1.35- 2.35 ) x 10 - 1 o cm2. s - 1 with ad sorotion activation enerv of 16.33 kl. mol - 1. 展开更多
关键词 Adsorption Kinetics n-Hexane MIL-101 Heterogeneity
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