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Science China chemistry 2009年第8期52卷 1171-1175页

作者： XU GaoChao,LIU RuiQuan & WANG Jin college of chemistry and Chemical Engineering,Xinjiang University,Urumqi 830046,China college of chemistry and Chemical Engineering Xinjiang University Urumqi China

Samaria-doped ceria Ce0.8Sm0.2.2.δ(SDC) and SmFe0.7Cu0.3-xNixO3 have been synthesized by the sol-gel method and characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM) and scanning electron microscopy(SEM).The electrochemical synthesis of ammonia was investigated at atmospheric pressure and low temperature,using the SFCN materials as the cathode,a Nafion membrane as the electrolyte,nickel-doped SDC(Ni-SDC) as the anode and silver-platinum paste as the current *** was synthesized from 2. to 100℃ when the SFCN materials were used as cathode,with SmFe0.7Cu0.1Ni0.2.3 giving the highest rates of ammonia *** maximum rate of evolution of ammonia was 1.13 × 10-8 mol·cm-2.s-1 at 80℃,and the current efficiency reached as high as 90.4%.

关键词： electrochemical synthesis of ammonia ammonia synthesis at atmospheric pressure and low temperature Nafion membrane metal oxide

The Synthesis of Podophyllotoxin Derivatives with Macrocyclic Dilactone

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Chinese Chemical Letters 1999年第4期10卷 275-276页

作者： Min YANG Ning CHEN Xin Fu PAN Bing Chang QIN(Department of chemistry. National Laboratory of Applied Organic chemistry,Lanzhou University, Lanzhou, 730000)(Department of chemistry, Anyang Teachers college. Anyang 455002. Department of chemistry Natl. Lab. of Appl. Organ. Chemistry Lanzhou University Lanzhou 730000 China Department of chemistry Anyang Teachers College Anyang 455002 China

Starting from podophyllotoxin, five new derivatives with macrocyclic dilactone 5 similar to 9 have been synthesized,and their structures were confirmed by IR, MS,H-1 NMR as well as HRMS. The key step is cyclization by... 详细信息

关键词： podophyllotoxin derivatives macrocyclic dilactone synthesis

Application of Genetic Programming in Predicting Infinite Dilution Activity Coefficients of Organic Compounds in Water

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Chinese Chemical Letters 2003年第9期14卷 987-990页

作者： Yi Lin CAO, Huan Ying LI college of chemistry and Environmental Science, Henan Normal University, Xinxiang 453002 Coll. of Chem./Environmental Science Henan Normal University Xinxiang 453002 China

In this paper, we calculated 37 structural descriptors of 174 organic compounds. The 154 molecules were used to derive quantitative structure - infinite dilution activity confficient relationship by genetic programming, the other 2. compounds were used to test the model. The result showed that molecular partition property and three-dimensional structural descriptors have significant influence on the infinite dilution activity coefficients.

关键词： Infinite dilution activity coefficients genetic programming.

Nucleophilic reactions of 1-methyl-2.methoxy-2.phenyl-3-oxo-2.3-dihydroindole

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Chinese Journal of chemistry 1996年第3期14卷 265-270页

作者： LING, Ke-QingDepartment of chemistry, Huaibei Coal Industry Teacher’s college, Huaibei, Anhui 2.5000, China Department of chemistry Huaibei Coal Indust. Teach.'s Coll. Huaibei Anhui 235000 China

The title compound (1) was prepared via methylene blue (MB)-sensitized photooxygenation of 1-methyl-2.phenylindole (2.) in methanol. Acid-catalyzed nucleophilic substitution of 1 with nucleophiles gave 1,2.2.trisubstituted 3-oxo-2.3-dihydroindoles (3-6). lithium aluminum hydride, followed by acidic workup yielded 4d and 2., whereas the same reduction reaction of 1, followed by neutral workup gave 1-methyl-2.phenyl-3-hydroxy-2.3-dihydroindole (15), together with 3. The reaction pathways of nucleophilic substitution and reduction of 1 were discussed.

关键词： 1-methyl-2.methoxy-2.phenyl-3-oxo-2.3-dihydroindole nucleophilic substitution reduction

Hydroisomerization of n-heptane over bimetal-bearing H_3PW_(12.O_(40) catalysts supported on dealuminated USY zeolite

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Science China chemistry 2008年第2期51卷 120-127页

作者： WEI RuiPing1,2. GU YanBo1 & WANG Jun1 1 State Key Laboratory of Materials-Oriented Chemical Engineering, college of chemistry and Chemical Engineering, Nanjing Uni- versity of Technology, Nanjing 2.0009, China 2.college of chemistry and Chemical Engineering, Southeast University, Nanjing 2.1189, China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing China college of chemistry and Chemical Engineering Southeast University Nanjing China

The bimetal-bearing (CePt or LaPt) 12.tungstophosphoric acid (H3PW12.40 (PW)) catalysts supported on dealuminated USY zeolite (DUSY) were prepared by impregnation and characterized by XRD, BET, IR, and H2.chemisorption. Their catalytic activities were tested in the hydroisomerization of n-heptane with a continuous atmospheric fixed-bed reactor. After the steam treatment combined with the acid leaching, as well as the supporting with PW and the bimetals, the DUSY support retains the Y zeolite porosity and the PW well keeps its Keggin structure in catalysts. The doping of Ce into the catalysts enhances the dispersion of Pt on the catalyst surface. The Pt-bearing PW catalysts doped with Ce or La, especially Ce, exhibit much higher catalytic activity and selectivity than the catalysts without dopants at lowered reaction temperatures. At the optimal reaction conditions, i.e., the reaction temperature of 2.0℃ and WHSV of 1.4 h1, the catalyst with a Pt loading of 0.4%, PW loading of 10% and a molar ratio of Ce to Pt of 15:1 shows a conversion of n-heptane of 70.3% with a high selectivity for isomerization products of 94.1%.

关键词： hydroisomerization of n-heptane bimetal catalyst heteropoly acid USY platinum

Cellulose conversion to polyols on supported Ru catalysts in aqueous basic solution

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Science China chemistry 2010年第7期53卷 1476-1480页

作者： DENG TianYin,SUN JiYing & LIU HaiChao Beijing National Laboratory for Molecular Sciences,State Key Laboratory for Structural chemistry of Stable and Unstable Species Green chemistry Center,{2. of chemistry and Molecular Engineering,Peking University,Beijing 100871,China Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Stable and Unstable Species Peking University Beijing China Green chemistry Center College of Chemistry and Molecular Engineering Peking University Beijing China

It is of great significance and challenge to achieve direct conversion of cellulose to specific polyols,e.g.,ethylene glycol and propylene *** such selective conversion,a novel one-pot approach was studied by combination of alkaline hydrolysis and hydrogenation on supported Ru catalysts.A wide range of bases including solid bases,e.g.,Ca(OH)2.and La2.3,and phosphate buffers were examined in the cellulose reaction in water,and the cellulose conversions and polyol products depended largely on the basicity or pH values in the aqueous *** glycol,1,2.propanediol,and especially 1,2.5-pentanetriol were obtained with selectivities of 15%,14% and 2.%,respectively,at 38% cellulose conversion at pH 8 in phosphate buffer *** preliminary results provide potentials for efficient conversion of cellulose to targeted polyols by using the advantages of bases.

关键词： cellulose polyols Ru catalysts solid bases aqueous basic solutions

EFFECT OF MOLECULAR WEIGHT OF PEO ON THE STRUCTURE AND PROPERTIES OF PDMAEMA/PEO HYDROGELS

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Chinese Journal of Polymer Science 2006年第1期24卷 35-40页

作者： Zhu-gen Liu Min Yi Mao-lin Zhai and Hong-fei Ha Department of Applied chemistry and The Key Laboratory of Polymer chemistry and Physics of Ministry of Education,{2. of chemistry & Molecular Engineering,Peking University,Beijing 100871,China Department of Applied chemistry and The Key Laboratory of Polymer chemistry and Physics of Ministry of Education College of Chemistry & Molecular Engineering Peking University Beijing 100871 China

A new kind of binary hydrogels composed of poly（dimethylaminoethylmethacrylate）（PDMAEMA） and poly（ethylene oxide）（PEO） with varying weight average molecular weights （M^-w = 5 × 10^4, 1 × 10^5 and 2.5 × 10^6） were prepared by У-irradiation technology. The properties of PDMAEMA/PEO hydrogels obtained were evaluated in terms of gel fraction, gel strength, thermal characterization and swelling behavior. The gel strength and swelling degree of the hydrogels could be improved obviously after adding PEO into the PDMAEMA system, while the degree of improvement decreased with increasing M^-w of PEO. The temperature sensitivity of PDMAEMA/PEO was retained only in the sample with PEO of M^-w = 5 × 10^4, and the pH sensitivity was retained in samples with PEO of M^-w = 5 × 10^4 and 1 × 10^5. When DMAEMA/PEO mixtures containing PEO of M^-w = 5 × 10^4 were irradiated, the main reaction could be the cross-linking of DMAEMA, and the linear PEO molecular chains could penetrate into the cross-linked network of PDMAEMA. With increasing M^-w of PEO, some side reactions were induced, such as grafting of DMAEMA onto PEO molecules, the scission or cross-linking of PEO.

关键词： Poly(dimethylaminoethylmethacrylate) Poly(ethylene oxide) Molecular weight Binary hydrogels Irradiation.

Sol-gel preparation and characterization of Li_(1.3)Al_(0.3)Ti_(1.7)(PO_4)_3 sintered with flux of LiBO_2

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Rare Metals 2010年第5期29卷 515-518页

作者： WU Xianming,LI Runxiu,CHEN Shang,HE Zeqiang,and MA Mingyou college of chemistry and Chemical Engineering,Jishou University,Jishou 416000,China college of chemistry and Chemical Engineering Jishou University Jishou China

Li1.3Al0.3Ti1.7（PO4）3 pellets sintered with different mole fractions of LiBO2.were prepared by sol-gel method. The structural identification, surface morphology, ionic conductivity, and activation energy of the pellets were studied by X-ray diffraction, scanning electron microscopy, and electrochemical impedance spectroscopy. The results show that all the Li1.3Al0.3Ti1.7（PO4）3 pellets sintered with different mole fractions of LiBO2.have similar X-ray diffraction patterns. The sintered pellet becomes denser and the boundary and comer of the particles become illegible with the increase of LiBO2. Among the Lil.3Al0.3Ti1.7（PO3）4 pellets sintered with different mole fractions of LiBO2. the one sintered with 1 mol% LiBO2.shows the highest ionic conductivity of 3.95×10^-4 ***^-1 and the lowest activation energy of 0.2.69 eV.

关键词： phosphates sol-gel process sintering ionic conductivity electrochemical impedance spectroscopy

Hydrothermal synthesis and characterization of rare-earth ruthenate pyrochlore compounds R_2.u_2._7(R=Pr_(3+),Sm(3+)-Ho(3+))

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Science China chemistry 2011年第6期54卷 941-946页

作者： YAO LinRan, WANG Dong, PENG Wen, HU WeiWei, YUAN HongMing & FENG ShouHua State key Laboratory of Inorganic Synthesis and Preparative chemistry college of chemistry, Jilin University, Changchun 13002., China State key Laboratory of Inorganic Synthesis and Preparative chemistry college of chemistry Jilin University Changchun China

A series of pyrochlore oxides, R2.u2.7 (R=Pr3+, Sm3+–Ho3+) were synthesized under mild hydrothermal conditions. All the samples crystallize in uniform octahedron characteristically. The products were characterized by powder X-ray diffraction, scanning electron microscopy, energy-disperse X-ray spectroscopy, and dc susceptibility, and the factors that affected the crystallization were discussed. It was found that the purity of products depends strongly on the raw materials and the amount of alkalinity in the initial reaction mixtures. The ZFC and FC susceptibilities of all of the compounds R2.u2.7 at low temperature were also measured and discussed.

关键词： hydrothermal synthesis pyrochlore compounds magnetic properties

Synthesis of Macrocyclic Arsinous Acid Esters

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Chinese Chemical Letters 1999年第12期10卷 0-0页

作者： Xin You CHENI Ying Qin YANG Wen Tian TAO(1’Department of chemistry, Xiaogan Teachers college, Hubei 432.00)(2.epartment of chemistry, Xinyang Teachers college, Henan 464000)(3Department of chemistry, Wuhan University, Wuhan 430072. Department of chemistry Xiaogan Teachers College Hubei 432100 China Department of chemistry Xinyang Teachers College Henan 464000 China Department of chemistry Wuhan University Wuhan 430072 China

The reactions of the his (dimethylamino) alkylarsine with dids lead to the formations ofmacrocyclic arsinous acid esters. The synthesis of title compounds was described and theirslructures were characterized by elemen... 详细信息

关键词： Bis (dimethylamino) alkylarsine macrocyclic arsinous acid ester synthesis.