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Preparation of nanometer perovskite-type oxide La_(0.8)Sr_(0.2)MnO_3 by organic solvent sol-gel method and capability testing

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Rare Metals 2008年第2期27卷 131-133页

作者： HU Jie SHAO Guangjie HUANG Hao XING Guangzhong State Key Laboratory of Metastable Materials Science ＆ Technology Yanshan University Qinhuangdao 066004 China Department of Environment and Chemistry Yanshan University Qinhuangdao 066004 China

A perovskite-type oxide, La0.8Sr0.2MnO3, was synthesized by the organic solvent sol-gel method. The desired metal cations were chelated in a solution by using citric acid as the chelating agent and absolute ethanol as the solvent. The thermal decomposition of the metal carboxylate precursor gels was studied by thermogravimetric/differential thermal analyzer （TG/DTA） and the products derived from calcining the gels were characterized by X-ray diffraction （XRD） and transmission electronic microscope （TEM）. The polarization curves were acquired on an electrochemical workstation （LK98） and the discharge curves were acquired on a testing instrument of batteries （DC-5）, with a constant current discharge, less than 120 mA/cm^2. The results revealed that the nanometer perovskite-type powder with lesser particle size could be achieved with an organic solvent and had a better catalytic activity.

关键词： nanometer-materials perovskite organic solvent catalytic activity

Effect of organic solvent and Resin on Luminescent Capability of SrAl_2O_4:Eu^(2+),Dy^(3+) Phosphor

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Journal of Rare Earths 2006年第Z2期24卷 160-161页

作者：钟海涛董岩蒋建清何锦华缪昌文 Jiangsu Bote New Materials Co. Ltd. Department of Material Science and Engineering Southeast University

organic substance such as solvent and resin's effect on luminescent capability of SrAl2O4:Eu2+ , Dy3+ phosphor was studied. Some organic solvents and resins were selected for experimentation. The results indicate that those organic solvents will not have negative effect on the applied capability of SrAl2O4:Eu2+ , Dy3+ phosphor. Adopting the organic resins and covering method, the afterglow luminance of SrAl2O4:Eu2+ , Dy3+ phosphor was increased by 85.01% and 82.51%.

关键词： organic solvent organic resin effect luminescent capability SrAl2O4:Eu2+ Dy3+ phosphor rare earths

Study of the Liquid Phase Volume Expansion for CO_2/organic solvent Systems

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Chinese Journal of Chemical Engineering 2005年第4期13卷 504-509页

作者： LI Zhiyi（李志义） XIA Yuanjing（夏远景） LIU Xuewu（刘学武） DENG Xiaoliang（邓小亮） Hu Dapeng（胡大鹏） R＆D Institute of Fluid and Powder Engineering Dalian University of Technology Dalian 116012 China

The supercritical antisolvent （SAS） process has been developed in recent years for the tormation of nanoand micro-particles. It is necessary to study the liquid phase volume expansion （LPVE） and find the relationships between the operating conditions and the LPVE in order to develop a practical method for determining the operation conditions and selecting an organic solvent for SAS process. The PR equation of state with vdW-1 mixing rule is used to calculate the LPVE for CO2/toluene, CO2/acetone and CO2/ethyl acetate systems, and the results show that the LPVE for each CO2/organic solvent system decreases as the temperature increases. The relationship between the LPVE and the solubility of CO2 in the liquid phase for CO2/organic solvent systems is investigated, and the results show that the LPVE is determined directly by the solubility of CO2 in the liquid phase, xCO2, and can be related to xCO2 independently. No matter what system of CO2/organic solvent is and how different the temperature is, the LPVEs have little difference as long as the solubility of CO2 in the liquid phase, xCO2, keeps constant. The lower temperature is always favorable to the SAS process. The higher the solubility of CO2 in an organic solvent under certain operation condition, the more suitable it is to the SAS process.

关键词： supercritical antisolvent process liquid phase volume expansion carbon dioxide organic solvent

The Desalting Property of Ion-Exchange Resins in organic solvent

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Chinese Journal of Chemical Engineering 2002年第5期10卷 567-569页

作者：王纪孝王世昌郝聚民路国梁 Chemical Engineering Research Center Tianjin University Tianjin 300072 China Department of Chemistry Hebei Normal University Shijiazhuang 050016 China

the desalting property of ion-exchange resins in organic solventis reported by using potassium acetate as a model compound. Theexperimental results show that solvability of the solvent, stirringspeed, and temperature are the factors which influence theion-exchange rate. The increase of solvability, stirring speed andtemperature will speed up the ion-exchange process.

关键词： desalination ion-exchange ion-exchange resins organic solvent

Theoretical investigations of transport properties of organic solvents in cation-functionalized graphene oxide membranes： Implications for drug delivery

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Nano Research 2018年第1期11卷 254-263页

作者： Kai Song Yong Long Xun Wang Gang Zhou State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Key Lab of organic Optoelectronics and Molecular Engineering Department of Chemistry Tsinghua University Beijing 100084 China

We perform detailed quantum chemical calculations to elucidate the origin and mechanism of the selective permeability of alkali and alkaline earth cation- decorated graphene oxide （M-GO） membranes to organic solvents. The results show that the selectivity is associated mainly with the transport properties of solvents in the membranes, which depends on two regions of the flow path： the sp3 C-O matrix of the GO sheets and the cation at the center of the hexagon rather than the sp~ region. According to the delocalization of ~ states in sp2 regions, we propose a design guide for high-quality M-GO membranes. The solvent-cation interaction essentially causes directional transport of molecules in the M-GO membranes under the transmembrane pressure, indicating a site-to-site mech- anism. The solvent-sp3 C-O matrix interaction may inhibit molecular transport between two fixed cations by consuming energy. The competition between energy consumption by the solvent-cation interaction and energy expenditure by the solvent-sp3 C-O matrix interaction leads to various transport properties of solvents and thus allows for the selective permeability of the M-GO membranes. Findings from the study are helpful for the future design of multifunctional M-GO macro-membranes as cost-effective solution nanofilters in chemical, biological, and medical applications

关键词： alkali and alkaline earthcation-decorated grapheneoxide (M-GO) membrane organic solvent permeability transport density functional theory

Photodegradation of new herbicide HW-02 in organic solvents

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Journal of Environmental Sciences 2010年第11期22卷 1774-1778页

作者： Zhongbin Lu Zhiguang Hou Xiumei Wang Siwei Wang Yanyan Shang Xing Yuan College of Urban and Environmental Science Northeast Normal University Changchun 130024 China. College of Resource and Environmental Science Jilin Agricultural University Changchun 130118 China The Center for Measurement and Test Jilin Agricultural University Changchun 130118 China Institute of Modernization Jilin Agricultural University Changchun 130118 China

HW-02 is a new organophosphates herbicide which is discovered and developed in China. The kinetics and mechanism of HW-02 photodegradation in the organic solvents were studied at 25°C under the irradiation of ultraviolet light. The results showed that photochemical reaction of HW-02 in organic solvents such as n-hexane, methanol, dimethyl benzene and acetone under UV light could be well described by the first kinetic equation, and the photodegradation efficiency decreased with a order of n-hexane methanol xylene acetone. The photodegradation efficiency constant of HW-02 in n-hexane, methanol, xylene and acetone were 4.951 × 10^-2 , 3.253 × 10^-2 , 2.377 × 10^-2 and 1.628 × 10^-2 min 1 , and the corresponding half-lives were 13.99, 21.20, 29.15 and 42.56 min, respectively. By separation and identification of photoproducts using GC-MS, it could be concluded that HW-02 was photolyzed through ester cleavage, photo-dechlorination and photoisomerization of the molecule itself.

关键词： HW-02 organic solvent photodegradation kinetics degradation mechanism

An Environmentally-Friendly and Catalytic Procedure for Mukaiyama Aldol Reaction Using organic Catalyst DBU under solvent Free Conditions

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有机化学 2004年第Z1期24卷 264-页

作者： SHEN,Zhi-Liang JI,Shun-Jun LOH,Teck Peng Key Laboratory of organic Synthesis of Jiangsu Province College of Chemistry and Chemical Engineering Suzhou University Suzhou 215006 Department of Chemistry National University of Singapore 3 Science Drive 3 Singapore 117543 Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry and Chemical Engineering Suzhou University Suzhou 215006 Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry and Chemical Engineering Suzhou University Suzhou 215006 Department of Chemistry National University of Singapore 3 Science Drive 3 Singapore 117543

　　Recently, methods based exclusively on organic catalysts have become of major significance in synthetic ***-aldol reaction, as one of the most important and frequently utilized methods for C-C bond formation, is well documented in literatures recently. A variety of reagents, particularly metal-containing Lewis acids or bases, are known to promote the nucleophilic process. However, many of the reported strategies might have the following limitations from environmental viewpoints: (1) the use of metal-containing catalyst. Some of the catalysts are air or moisture sensitive (such as lithium amide), and crucial reaction conditions are needed; Some of the catalysts derived from poisonous metal (for example: SnCl4, SmI2 etc.) may cause harmful influence on humane body and environment; (2) the use of organic solvent (such as DMF, CH2Cl2 etc.) may bring about environmental pollution and solvent waste.……

关键词： solvent Free environmental pollution organic solvent methods for Lewis acids

Synthesis of Fragment Derivatives of Delta Sleep-inducing Peptide （1-4） Catalyzed by Enzymes in organic solvents

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Chinese Journal of Chemistry 2005年第5期23卷 640-642页

作者：沈鸿雁田桂玲洪毅颖李恒叶蕴华 KeyLaboratoryofBioorganicChemistryandMolecularEngineering MinistryofEducationCollegeofChemistryandMolecularEngineeringPekingUniversityBeifing100871China

Synthesis of two fragment derivatives of delta sleep‐inducing peptide (DSIP) (1‐4), Boc‐Trp‐Ala‐Gly‐GlyNH‐NHPh ( 1 ) and Boc‐Trp‐Ala‐Gly‐GlyOEt ( 2 ), catalyzed by proteases via 2+2 or 1+3 synthetic routes with different protecting groups at C‐terminal in organic solvents was reported. The yield of N‐Boc tetrapeptide with phenylhy‐drazinyl protecting carboxyl group at C‐terminal ( 1 ) was higher than that of N‐Boc tetrapeptide ethyl ester ( 2 ) by2+2 route. The factors influencing the synthetic yield of the fragments of DSIP (1‐4) were discussed.

关键词： DSIP enzymatic synthesis organic solvent peptide

A simple method for determining water content in organic solvents based on cobalt(Ⅱ) complexes

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Chinese Chemical Letters 2011年第2期22卷 189-192页

作者： Lin Zhou Xiao Hua Liu Hai Xin Bai Hong Juan Wang College of Plant Protection Henan Agricultural UniversityZhengzhou 450002China College of Sciences Henan Agricultural UniversityZhengzhou 450002China

A method to determine water content in organic solvents was developed based on the color change of cobalt（Ⅱ） nitrate in different *** color-change mechanism and optimal conditions for determining the water content were *** results showed that there was a good linear relationships between the absorbance of cobalt（Ⅱ） complexes in organic solvents and water contents withγin 0.9989～*** method has the advantages of low cost,good reproducibility,good sensitivity,simple in operation,fast in detection,friendly to the environment and no limitation on linear range for determining water *** was used to determine water in samples with a satisfactory recovery in 97.81%～101.24%.

关键词： Determination Water content Cobalt(Ⅱ) nitrate organic solvent