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Aminolysis of ethyl acetate in continuous flow and its reaction kinetics

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Chinese Journal of Chemical Engineering 2019年第12期27卷 2948-2952页

作者： Tao Shen Bo Ouyang Chao Qian Xinzhi Chen Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Zhejiang Garden Biochemical High-Tech Co. LTDDongyan 322121China Research Institute of Zhejiang University-Quzhou Quzhou 324000China

The aminolysis of ethyl acetate was promoted significantly via continuous reaction in a tubular *** was thus synthesized without presence of solvent and *** optimum conditions were obtained as follows:the reaction temperature is 218℃,the reaction pressure is 3.5 MPa,the molar ratio(ethyl acetate:N-propylamine)is 1:1,and the residence time is 350 ***,the conversion of ethyl acetate is up to94.8%.Furthermore,the kinetics of the rapid reaction stage(when the conversion of ethyl acetate is 20%-80%)can be expressed as Ink=-4629.441/T+2.1366,and the apparent activation energy is Ea=38489 J·mol-1.

关键词： Tubular reactor Reaction kinetics ethyl acetate Aminolysis

Enantioselective hydrolysis of naproxen ethyl ester catalyzed by polyclonal antibodies

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Chinese Science Bulletin 1997年第9期42卷 741-744页

作者： Hu, YJ Yang, BH Zhao, H Wu, YL Ji, YY Ye, M State Key Laboratory of Bicorganic and Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai China Shanghai Institute of Cell Biology Chinese Academy of Sciences Shanghai China

BASED on the hypothesis of Pauling on enzyme action that free energy difference between theground and transition state is reduced by the specific binding of active center of enzyme to theintermediate,a large number of... 详细信息

关键词： enantioselectivity hydrolysis of naproxen ethyl ester polyclonal antibody catalytic antibody.

An Alternative Synthesis and Crystal Structure Characterization of Nutrient Fortifier N-(1-(Phenylacetyl)-L-prolyl) Glycine ethyl Ester

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Chinese Journal of Structural Chemistry 2019年第10期38卷 1727-1734,1611页

作者：李艳如崔建兰于思源钟丛杉王宁王晓 School of Chemical Engineering and Technology North University of China

A nutritional fortifier N-(1-(phenylacetyl)-L-prolyl)glycine ethyl ester(4)was successfully synthesized through two synthetic schemes and characterized by IR,^1H-NMR,^13C-NMR,elemental analysis and X-ray single-crystal *** intermediate N-phenylacetyl-L-proline(2)was synthesized by the solid-liquid reaction of L-proline and phenylacetyl chloride *** 2(C13 H15 NO3,Mr=233.26)belongs to the orthorhombic system,space group P212121 with a=8.9468(3),b=9.3190(3),c=14.0453(4)A,V=1171.03(6)A^3,Z=4,Dc=1.323 g/cm^3,μ=0.773 mm^-1,F(000)=496.0,the final R=0.0313 and wR=0.0797 for all *** 4(C17 H22 N2 O4,Mr=318.36)is of orthorhombic system,space group P212121 with a=6.5831(2),b=8.5536(2),c=28.9138(9)A,V=1628.11(8)A^3,Z=4,Dc=1.299 g/cm3,μ=0.763 mm-1,F(000)=680.0,the final R=0.0353 and wR=0.0816 for all data.

关键词： N-(1-(phenylacetyl)-L-prolyl) glycine ethyl ester N-phenylacetyl-L-proline dicyclohexyl-carbodiimide crystal structure glycine ethyl ester hydrochloride

Behavior of surface action between ethyl thiourea and chalcopyrite

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中国有色金属学会会刊：英文版 2000年第5期10卷 687-690页

作者：蒋玉仁薛玉兰 Cent S Univ Technol Dept Mineral Engn Changsha 410083 Peoples R China

The behavior of surface action between ethyl thiourea (ETU) and chalcopyrite was studied by means of measurement of adsorptive amount, IR and XPS. The adsorption behavior of ETU on chalcopyrite corresponds to Freundlich adsorption isothermal equation, which is Г =6.31×10 -5 c 0.31 mol/g. The adsorption is a covalent bond type of chemical one composed of two σ type bonds and a back donation π type, mainly occurs between sulfur and nitrogen atom in ETU and copper atoms on the surface of chalcopyrite. For the two σ type bonds, one is formed by transferring a pair of electrons from sulfur atom in ETU to copper atoms on the surface of chalcopyrite, the other is from nitrogen atom. And the π type bond is caused by transfer of electrons from copper atoms on the surface of chalcopyrite to unoccupied π type orbit of CS group in ETU. Theoretical index predicts that ETU can be an excellent kind of chelating collector for copper flotation. [

关键词： ethyl thiourea chalcopyrite surface action adsorption characteristic flotation reagents

THE INTERACTION OF ethyl BENZOATE AND TRIFLUOROACETIC ACID IN EXCITED STATE

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Science China Chemistry 1992年第8期35卷 925-930页

作者：白凤莲樊琳虞群叶建平 Institute of Chemistry Academia Sinica Beijing 100080 PRC Institute of Photographic Chemistry Academia Sinica Beijing 100101 PRC

This paper is concerned with the interaction of ethyl benzoate (EBA) and trifluoroaceticacid (TFA) molecules in the excited state by measurements of steady--state and transient fluo-rescence spectra at room and low temperatures. The results show that not only the 1:1 exci-plex but also the 2:1 triplex between EBA and TFA was formed. The formation pathway ofthe triplex is that the exciplex formed at first, then by the interaction with the EBA mole-cule it transformed into triplex. But it could not be formed by the dimer of EBA by interac-tion with TFA. The dimer of EBA is confirmed in the concentrated solution. So there arefour components in EBA/TFA--concentrated solution and their fluorescence lifetimes aremeasured respectively.

关键词： ethyl benzoate trifluoroacetic acid exciplex triplex dimer

O- and C-alkylations of ethyl nitroacetate with benzyl halides

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Chinese Science Bulletin 1997年第19期42卷 1628-1631页

作者： Kang, F Yin, HY Yin, CL Department of Chemistry Beijing Normal University Beijing 100875 China

THE chemistry of nitronic esters remains relatively unknown due to their conspicuous feature ofinstability. In the preceding papers, we described the late progress in the researchof nitronic esters: (i) nitronic ester... 详细信息

关键词： ethyl nitroacetate benzyl halides O-alkylation C-alkylation.

HIGH－PERFORMANCE　CAPILLARY　ELECTROPHORESIS　OF　REDUCING　OLIGOSACCHARIDES　AS　THEIR　ethyl　P－AMINOBENZOATE　DERIVATIVES

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Chinese Chemical Letters 1996年第2期7卷 159-160页

作者： Chang, LW Guo, Q Yu, ZL Chen, Y Zhu, A ACAD SINICA INST CHEMBEIJING 100080PEOPLES R CHINA

A modified method for the separation of oligosaccharides derivatized with p-aminoben-zoate ethyl ester by high performance capillary electrophoresis (HPCE) is described. The isomers of larger oligosaccharides up to 10... 详细信息

关键词： AS OLIGOSACCHARIDES THEIR ethyl CAPILLARY AMINOBENZOATE

Pressure Swing Distillation for Separation of ethyl Acetate and Ethanol in Sub-plateau Region

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China Petroleum Processing & Petrochemical Technology 2020年第1期22卷 104-110页

作者： Wang Keliang Li Jing Lian Minglei Li Zhi Du Tingzhao College of Chemistry and Materials Engineering Liupanshui Normal UniversityLiupanshui 553004 North China Company China Petroleum Engineering Co.Ltd.Renqiu 062552

The pressure swing distillation(PSD)process for separation of ethyl acetate and ethanol mixture in subplateau region was *** pressure of low-pressure column was set at 0.086 MPa,which is in accordance with the atmospheric pressure in the Yunnan-Guizhou region,while the pressure of high-pressure column was determined as 0.304 *** design parameters,including the plate number,the reflux ratio,and the feeding positions,were optimized,while taking into consideration the total annual cost(TAC).Furthermore,based on the general PSD,the partially heatintegrated pressure swing distillation(PHIPSD)process and the fully heat-integrated pressure swing distillation(FHIPSD)process were also *** processes with heat integration showed lower capital cost and lower energy cost,and TACs of the PHIPSD and FHIPSD decreased to 377.21×103$/a and 371.66×103$/a,*** with the non-heat integrated process,TACs of the PHIPSD and FHIPSD could be reduced by 27.82%and 28.89%,*** results showed that the FHIPSD process could effectively separate the ethyl acetate-ethanol mixture,and it was more economical and *** work can provide some technical references for the separation of such azeotropes in the sub-plateau region.

关键词： pressure swing distillation ethyl acetate ethanol azeotrope heat-integrated

Superior gallstone dissolubility and safety of tert-amyl ethyl ether over methyl-tertiary butyl ether

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World Journal of Gastroenterology 2019年第39期25卷 5936-5952页

作者： Dong Do You Suk Joon Cho Ok-Hee Kim Jin Sook Song Kyu-Seok Hwang Sang Chul Lee Kee-Hwan Kim Ho Joong Choi Ha-Eun Hong Haeyeon Seo Tae Ho Hong Jung Hyun Park Tae Yoon Lee Joseph Ahn Jae-Kyung Jung Kwan-Young Jung Say-June Kim Department of Surgery St.Vincent's HospitalCollege of MedicineThe Catholic University of KoreaSeoul 16247South Korea College of Pharmacy Chungbuk National UniversityCheongju 28644South Korea Department of Surgery Seoul St.Mary’s HospitalCollege of Medicinethe Catholic University of KoreaSeoul 06591South Korea Catholic Central Laboratory of Surgery Institute of Biomedical IndustryCollege of Medicinethe Catholic University of KoreaSeoul 06591South Korea Bio and Drug Discovery Division Korea Research Institute of Chemical TechnologyDaejeon 34114South Korea Department of Surgery Daejeon St.Mary's HospitalCollege of Medicinethe Catholic University of KoreaSeoul 34943South Korea Department of Surgery Uijeongbu St.Mary's HospitalCollege of Medicinethe Catholic University of KoreaSeoul 11765South Korea Department of Biomedicine and Health Science College of Medicinethe Catholic University of KoreaSeoul 06591South Korea Department of Surgery Eunpyeong St.Mary’s HospitalCollege of Medicinethe Catholic University of KoreaSeoul 03312South Korea Department of Medicinal Chemistry and Pharmacology University of Science and TechnologyDaejeon 34113South Korea

BACKGROUND The use of methyl-tertiary butyl ether(MTBE)to dissolve gallstones has been limited due to concerns over its toxicity and the widespread recognition of the safety of laparoscopic *** adverse effects of MTBE are largely attributed to its low boiling point,resulting in a tendency to ***,if there is a material with a higher boiling point and similar or higher dissolubility than MTBE,it is expected to be an attractive alternative to *** To determine whether tert-amyl ethyl ether(TAEE),an MTBE analogue with a relatively higher boiling point(102°C),could be used as an alternative to MTBE in terms of gallstone dissolubility and *** The in vitro dissolubility of MTBE and TAEE was determined by measuring the dry weights of human gallstones at predetermined time intervals after placing them in glass containers with either of the two *** in vivo dissolubility was determined by comparing the weights of solvent-treated gallstones and control(dimethyl sulfoxide)-treated gallstones,after the direct infusion of each solvent into the gallbladder in both hamster models with cholesterol and pigmented *** The in vitro results demonstrated a 24 h TAEE-dissolubility of 76.7%,56.5%and 38.75%for cholesterol,mixed,and pigmented gallstones,respectively,which represented a 1.2-,1.4-,and 1.3-fold increase in dissolubility compared to that of *** the in vitro experiment,the 24 h-dissolubility of TAEE was 71.7%and 63.0%for cholesterol and pigmented gallstones,respectively,which represented a 1.4-and 1.9-fold increase in dissolubility compared to that of *** addition,the results of the cell viability assay and western blot analysis indicated that TAEE had a lower toxicity towards gallbladder epithelial cells than *** We demonstrated that TAEE has higher gallstone dissolubility properties and safety than those of *** such,TAEE could present an attractive alternative to MTBE if our findings

关键词： Tert-amyl ethyl ether Gallstones Methyl-tert-butyl ether Contact litholytic agent