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Science China Chemistry 2009年第8期52卷 1097-1103页

作者： LI XiangJun,ZHENG Na,HU ZhongBo & YUAN ZhuoBin college of Chemistry and chemical engineering,Graduate university of Chinese Academy of Sciences,Beijing 100049,China 1. college of Chemistry and chemical engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12-type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

Formation and evolution mechanisms of large-clusters during rapid solidification process of liquid metal Al

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Science China(Physics,Mechanics & Astronomy) 2005年第1期48卷 101-112页

作者： LIU Rangsu, DONG Kejun, LIU Fengxiang, ZHENG Caixing, LIU Hairong & LI Jiyong Department of Applied Physics, Hunan university, Changsha 410082, China college of Materials Science and engineering, Hunan university, Changsha 410082, China college of Chemistry and chemical engineering, Hunan university, Changsha 410082, China 1. Department of Applied Physics Human University 410082 Changsha China 2. college of Materials Science and engineering Hunan University 410082 Changsha China 3. college of Chemistry and chemical engineering Hunan University 410082 Changsha China

A molecular dynamics simulation study has been performed for the formation and evolution characteristics of nano-clusters in a large-scale system consisting of 400000 atoms of liquid metal Al. The center-atom method combined with pair-bond analysis technique and cluster-type index method (CTIM) has been applied here to describe the structural configurations of various basic clusters. It is demonstrated that both the 1551 bond-type and the icosahedral cluster (12 0 12 0) constructed by 1551 bond-types are dominant among all the bond-types and cluster-types, respectively, in the system and play a critical role in the microstructure transitions of liquid metal Al. The nano-clusters (containing up to 150 atoms) are formed by the combination of some middle and small clusters with distinctly different sizes, through mutual competition by unceasing annex and evolution in a seesaw manner (in turn of obtaining and losing),which do not occur as the multi-shell structures accumulated with an atom as the center and the surrounding atoms are arranged according to a certain rule. This is the essential distinction of nano-cluster in liquid metal from those obtained by gaseous deposition, ionic spray methods, and so on. Though the nano-clusters differ from each other in shape and size, all of them possess protruding corners that could become the starting points of various dendrite structures in the solidification processes of liquid metals.

关键词： liquid metal, solidification process, large-cluster configuration, evolution mechanism, computer simulation.

Study on the Separation of Co^(2+) from Zn^(2+) , Cd^(2+) by Anion-exchange Chromatography

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Journal of Central South university 2000年第2期12卷 88-91页

作者： WANG Xin yan,ZHOU Chun shan,WANG Yan (college of Chemistry and chemical engineering, Central South university of Technology, Changsha 410083, China) 1. college of Chemistry and chemical engineering Central South University of Technology 410083 Changsha China

The separation of Co 2+ from Zn 2+ , Cd 2+ by anion exchange chromatography was discussed. The chromatographic column containing anion resin 201×7 which was saturated with a solution of ammonium chloride. The effects of the eluant acidity and eluant composition on the separation were investigated. The results indicate that this anion exchange chromatography is suitable to the separation of Co 2+ from Zn 2+ , Cd 2+ , and the condition of separation is simple and convenient. When the column is saturated with NH 4Cl solution (2.0 mol/L, pH=4.0), the separation can be completed effectively. Zn 2+ and Cd 2+ can also be separa ted when different eluants are used and the pure solution with high concentration of Zn 2+ , Cd 2+ respectively can be obtained ea sily.

关键词： anion exchange chromatography Zn 2+ Cd 2+ Co 2+ separation

Facile Synthesis of Isoamericanol and Isoamericanin A

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Chinese chemical Letters 2004年第12期15卷 1392-1394页

作者： Xiao Bi JING Chao Guo YAN Jing SUN Li WANG Lin AN college of chemistry and chemical engineering, Yangzhou university, Yangzhou 225002 college of chemistry and chemical engineering Yangzhou UniversityYangzhou 225002

A number of benzodioxane compounds were synthesized using the pal1adium-catalyzedetherification of aryl halides by employing triphenylphosphan ligand. This method was used askey step in the synthesis of isoamericanol ... 详细信息

关键词： Synthesis isoamericanol A isoamericanin A benzodioxane.

Pictet-Spengler condensation reactions catalyzed by a recyclable H^+-montmorillonite as a heterogeneous BrΦnsted acid

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Science China Chemistry 2010年第3期53卷 561-567页

作者： WANG YuFeng,SONG ZhanBo,CHEN ChunXia & PENG JinSong Department of Chemistry and chemical engineering,college of Science,Northeast Forestry university,Harbin 150040,China 1. Department of Chemistry and chemical engineering College of Science Northeast Forestry University Harbin 150040 China

Catalytic performance of different cation-exchanged montmorillonite clays has been investigated in the Pictet-Spengler C-C bond forming reaction.H+-Montmorillonite was found to be a very efficient and reusable catalyst for the endo cyclization of β-phenylethylamine derivatives with aldehydes under solvent-free *** addition,an aqueous condensation version for the synthesis of tetrahydro-β-carbolines using the H+-montmorillonite catalyst has been *** these environmentally friendly processes,the use of organic solvents was avoided and the catalyst was recycled with maintenance of high catalytic activity.

关键词： heterogeneous catalysis catalyst recycling mesoporous materials green synthesis

Synthesis and Characterization of Poly (Aryl Ether Ketone) Containing Phthalazinone and Naphthalene Moieties

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Chinese chemical Letters 2000年第9期11卷 777-778页

作者： Ye GAO Xi Gao JIAN Jin Yan WANG Department of polymer Science, college of chemical engineering, Dalian university of Technology, Dalian 116012 Dalian Univ Technol Coll Chem Engn Dept Polymer Sci Dalian 116012 Peoples R China

A novel poly (aryl ether ketone) (PPEK) containing phthalazinone and naphthalene moieties was prepared by the nucleophilic displacement reaction of 4-(4-hydroxyphenyl) (2H) phthalazin-1-one with 1-chloro-4-(4-chlorobe... 详细信息

关键词： engineering thermoplastics poly (aryl ether ketone) synthesis

Prediction of Water Activities in Multicomponent Solutions of Metal Chlorides from the Thermodynamic Properties of Corresponding Binary Systems

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Journal of Central South university 2000年第1期12卷 29-33页

作者： LI Yuan gao,ZHANG Quan ru,FANG Zheng(college of Chemistry and chemical engineering, Central South university of Technology, Changsha 410083, China) 1. college of Chemistry and chemical engineering Central South University of Technology 410083 Changsha China

In order to calculate the activity coefficients of water in aqueous solution of metal electrolytes, a simplified model predicting them in ternary or multicomponent solutions with common anions from the activity data of water of the corresponding binary systems has been developed based on an assumption that the electrolytes in the solution are treated as independent particles instead of their ion forms, and the interaction of the salt( i ) salt( j ) pair in the solution is assumed to be much weaker than that of water salt pair due to the common anions of both of salts. The model was applied to the systems such as KCl H 2O NaCl, MCl H 2O M′Cl 2 (M represents Na and K, M′ represents Ca and Ba) and KCl H 2O NaCl BaCl 2 with satisfying results. The interchange energies of the studied component pairs between water and salts have also been determined by the corresponding binary aqueous solutions.

关键词： activity of water electrolyte thermodynamic model interchange energy

Calcium Borate Catalysts Supported on Al-MCM-41 Mesoporous Materials as Catalyst for Ethoxylation

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Calcium Borate Catalysts Supported on Al-MCM-41 Mesoporous M...

A new way to synthesize benzoin isopropyl ether on Cu-Fe-hydrotalcite

作者： SONG Wei-Ming, DENG Qi-Gang , ZHAO De-Feng ( Stade Key Laboratory of Fine chemicals,Dalian university ofTechnology,Dalian 116012 college of Chemistry and chemical engineering of qiqihar university,qiqihar,161006)

＜正＞ Mesoporous molecular sieves containing aluminum ions （Al-MCM-41） with Si/Al ratio equal to 30 were used to supported calcium borate （CaB4O7） by microwave irradiation method. The CaB4O7/ Al-MCM-41 （CBA1M） were used in the Ethoxylation as catalysts .The results show that CBAlM has higher catalytic activity than Al-MCM-41 and CaB4O7. The reaction is carried out at 120℃in the presence of 5% catalyst in relation to the octanol. The homologue distributions of ethoxylates were determined by GC and HPLC measurements and that showed the homologue distributions of octanolpolyoxyethylene ether were narrowed using the CBA1M catalyst for alcohols ethoxylation.

关键词： Al-MCM-41 calcium borate support narrow-range ethoxylation

来源： cnki会议评论

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Journal of Natural Gas Chemistry 2010年第1期19卷 77-80页

作者： Xianmei Xie, Xia An, Kai Yan, Xu Wu, Jianling Song, Zhizhong Wang college of Chemistry and chemical engineering, Taiyuan university of Technology, Taiyuan 030024, Shanxi, China [a] college of Chemistry and chemical engineering Taiyuan University of Technology Taiyuan 030024 Shanxi China

An efficient synthesis of benzoin isopropyl ether with benzaldehyde and propanol in the presence of heterogeneous recyclable Cu-Fe-hydrotalcite catalyst has been explored. Cu-Fe-hydrotalcite was firstly successfully synthesized over Jahn-Teller effect of Cu^2＋. The catalytic test result showed that Cu-Fe-hydrotalcite could be used as a good catalyst in the synthesis of benzoin isopropyl ether. The highest conversion of ben- zaldehyde was 59.7% and the selectivity of benzoin isopropyl ether was nearly 100%. By this new method, not only was the cyanide poisoning avoided, but also the synthesis of benzoin isopropyl ether could be completed in one step instead of traditional two steps with both condensation and etherification.

关键词： benzoin isopropyl ether benzaldehyde propanol Cu-Fe-hydrotalcite

Synthesis and Crystal Structure of Bis(nitrate)- bis(N,N'-dimethyl-N,N'-dibenzenyl-urea)uranyl(Ⅱ)

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Chinese Journal of Structural Chemistry 2003年第5期22卷 521-524页

作者： ZHU Li-Ming LI Bao-Long② CAO Zheng-Bai ZHANG Yong (college of Chemistry and chemical engineering, Suzhou university, Suzhou 215006, China) college of Chemistry and chemical engineering Suzhou University Suzhou 215006

The new uranyl complex UO2(NO3)2[PhN(CH3)C(O)(CH3)NPh]2 was synthesized and its crystal structure has been determined by single-crystal X-ray diffraction. Crystal data: C30H32N6O10U, triclinic, space group P with a = 7.772(1), b = 9.267(1), c = 12.644(1) ? a = 68.246(8), b = 73.871(9), g = 84.99(1)o, V = 812.4(2) ?, Mr = 874.65, Z = 1, Dc = 1.788 g/cm3, F(000) = 426, m = 5.062 mm-1, the final R = 0.022 and wR = 0.059 for 3571 observed reflections (I > 2s(I)). The central uranyl ion is coordinated by six oxygen atoms, two from the carbonyl groups of N,N-dimethyl-N,N-dibenzenyl-urea molecules and the other four from two nitrate groups.

关键词： substituted urea uranyl complex synthesis crystal structure