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Study on Phase Equilibrium Properties for CO_(2)^+ Cosolvent Binary Systems

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Chinese Chemical Letters 2001年第9期12卷 829-832页

作者： Zhang Jing CHANG Wu Xiang YANG cao wei liang Faculty of Science Beijing University of Chemical TechnologyBeijing 100029

In this study, the constant volume, visual method is used to measure the critical point of CO2+toluene, CO2+cyclohexane, CO2+n-butyraldehyde, CO2+i-butyraldehyde, CO2+methanol and CO2+alcohol binary systems. The relationship between critical point and the concentration of the entrainer for different substances has been discussed, and the comparison of the phase behavior of single component system and that of binary systems have been carried out.

关键词： Critical point supercritical binary system phase equilibrium

Determination of Critical Parameters of Carbon Dioxide+Butyraldehyde System with Different Compositions

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Chemical Research in Chinese Universities 2005年第6期21卷 687-691页

作者： ZHANG Jing-chang GAO Xi-xin cao wei-liang Key Laboratory of Science and Technology of Controllable Chemical Reactions of Ministry of Education Institute of Modern Catalysis Beijing University of Chemical Technology Beijing 100029 P. R. China

Supercritical carbon dioxide（SC-CO2 ） is considered in green chemistry as a substitute for conventional solvents in chemical reactions due to its environmentally benign character. Recently we have reported the homogeneous hydroformylation of propylene in supercritical carbon dioxide（ SC-CO2 ） , which is an example of this kind of application of carbon dioxide. The determination for the critical parameters of carbon dioxide ＋ butyraldehyde mixtures is necessary for this reaction design which is the focus of the present paper. The critical parameters of the binary systems were determined via the static visual method at a constant volume with the molar fraction of butyraldehyde ranging from 1.0% to 2. 2% and the pressure ranging from 5 to 10 MPa. The experimental results show that the critical pressure and temperature increased with increasing the molar fraction of butyraldehyde. The bubble（dew） temperatures and the bubble （dew） pressures for the binary systems were also determined experimentally. The p-T Figures at different compositions of the binary systems were described. In addition, the critical compressibility factors Zc of the binary systems at different concentrations of n-butyraldehyde were calculated. It was found that the critical compressibility factor values of the binary systems decreased with increasing the molar fraction of n-butyraldehyde in the experimental range.

关键词： Carbon dioxide + butyraldehyde binary system Critical temperature Critical pressure p-T Figure Critical compressibility factor

Theoretical Investigation on Intermolecular Interactions Between HCCF and HCCR(R=F,Cl,Br)

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Chemical Research in Chinese Universities 2009年第6期25卷 929-935页

作者： WANG Zhao-xu ZHENG Bai-shu ZHANG Jing-chang cao wei-liang School of Chemistry and Chemical Engineering Hunan University of Science and Technology Xiangtan 411201 P. R. China Institute Of Modern Catalysis Beijing University of Chemical Technology State Key Laboratory of Chemical Resource Engi- neering Faculty of Science Beijing 100029 P. R. China

Geometries, interaction energies and electronic properties for four types of dimers（hydrogen bonded, halogen bonded, π-halogen bonded, and ~r-hydrogen bonded） between HCCF and HCCR（R=F, CI, Br） were studied via MP2/6-31 1＋＋G（d,p） ab initio calculation. It is shown that the strength of the zr-hydrogen bonded dimers turns out to be greater than those of the other three types of dimers, with the interaction energies --4.611 kJ/mol for HCCF-HCCF, -4.700 kJ/mol for HCCF-HCCC1, and -4.850 kJ/mol for HCCF-HCCBr respectively at the CCSD（T）/6-311＋＋ G（d,p）//MP2/6-31 1＋＋G（d,p） level. In an effort to understand the nature of the intermolecular interactions prevalent in these dimers, the interaction energies were decomposed into physically distinct energy components with the aid of the symmetry adapted perturbation theory（SAPT）. The dispersion force is found to be the main origin of the intermolecular interactions in hydrogen bonded and halogen bonded dimers. In the π-halogen bonded system, the dispersion is the major bonding force in HCCF-HCCF and HCCF-HCCC1, while the induction energy is the most important component in HCCF-HCCBr. However, both the dispersion and electrostatic energy play a key role in π-hydrogen bonded dimers.

关键词： Ab initio calculation Intermolecular interaction SAPT decomposition

Theoretical Study on the Tautomerization Reaction of Formamide to Formamidic Acid Encapsulated in a Nano-sized Molecular Container

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Chemical Research in Chinese Universities 2009年第1期25卷 102-107页

作者： WANG Xiu-li YANG Zuo-yin WANG Ju ZHANG Jing-chang cao wei-liang State Key Laboratory of Chemical Resource Engineering Faculty of Science Beijing University of Chemical Technology Beoing 100029 P. R. China

The hybrid calculations with ONIOM（B3LYP/6-31G＊：AM1） method were carried out on the tautomerization reaction of formamide to formamidic acid in the microcontainer-encapsulated state. The free-state tautomerization process was also investigated with B3LYP/6-31G＊＊//B3LYP/6-31G＊ method for the purpose of comparison. Bare tautomerization, H20-assisted（single-H20 or multiple-HaO） and self-assisted mechanisms were all taken into consideration for the encapsulated state. The results show that only bare tautomerization and single-H2O catalysis mechanisms are possible to the encapsulated formamide tautomerization owing to the container＇s size confinement effect. Geometrical changes in the complexed container and guest molecules are discussed to deeply understand the complex＇s structural properties. The bare tautomerization barrier in the encapsulated state increases by 23.826 kJ/mol, accounting for 12% of the corresponding total energy barrier in the free state, and the increased values for the single-H2O catalysis process are 12.958 kJ/mol, accounting for 16% of the corresponding total energy barrier, respectively. This finding suggests that the encapsulation can make the tautomerization process slightly difficult.

关键词： Formamide Tautomerization ONIOM calculations Host-guest complex

Theoretical Study on the Conformational Conversion of 1,3-Dioxane Inside a Capsular Host

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Chemical Research in Chinese Universities 2008年第2期24卷 241-245页

作者： WANG Ju YANG Zuo-yin WANG Xiu-li ZHANG Jing-chang cao wei-liang State Key Laboratory of Chemical Resource Engineering Faculty of Science BeOing University of Chemical Technology Beijing 100029 P. R. China

The mechanism for the conformational conversion of 1,3-dioxane guest encapsulated inside a capsular host was theoretically investigated using semiempirical PM3 method and DFT methods. The free-state process of the conformational conversion of 1,3-dioxane was also investigated to make a comparison between the two different states using the same theory. The influences of the inner phase of the capsule on the conformational conversion of guest molecule were discussed via analyzing the comparative results. It was found that the capsular host could accommodate 1,3-dioxane within its cavity by the weak attractive interactions between host and guest, and it responds to the conformational conversion of guest by the deformation of hydrogen-bonding seam at the middle of the capsule. When entrapped in the capsule, the guest molecule undergoes the conformational conversion from chair form to twist-boat form slower than that under the free condition. The deformation of the capsule is favorable to maximize the attractive interactions between host and guest.

关键词： Complex Cylindrical capsular host Host-guest interaction energy Quantum chemistry

A description of nitrogen-nitrogen bond in terms of charge distributions

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Chinese Journal of Chemistry 1990年第6期8卷 492-506页

作者： cao wei-liang MARSHALL T.C. BADER R.F.W. Department of Applied Chemistry Beijing Institute of Chemical TechnologyBeijing 100013 Department of Chemistry McMaster UniversityHamilton OntCanada L8S 4M1

A theoretical analysis of properties of the shared interactions between two neighbouring nitrogen atoms in a variety of compounds is presented, based on properties of charge distributions derived from 6-31 ++G** wave functions. Bond is characterized in terms of its bond order, bond ellipticity and the quantity of Laplacian of p at the bond critical point. The difference between the bond path angle and the corresponding geometrical angle provides a measure of the degree of relaxation for the charge density away from the geometrical constraints imposed by the nuclear framework. Comparisons have been made between the nitrogen-containing compounds and isoelectronic hydrocarbons. Values of the NN bond energies, based on the properties of NN bond interatomic surface, are determined in three schemes.

关键词： NN A description of nitrogen-nitrogen bond in terms of charge distributions

Preparation and Catalytic Application of Novel Water Tolerant Solid Acid Catalysts of Zirconium Sulfate/HZSM-5

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Chemical Research in Chinese Universities 2007年第3期23卷 349-354页

作者： JIANG Ya-jie JUAN Joon Ching MENG Xiu-juan cao wei-liang YARMO Mohd Ambar ZHANG Jing-chang State Key Laboratory of Chemical Resource Engineering Ministry of Education Institute of Modern Catalysis Beijing University of Chemical Technology Beijing 100029 P. R. China Advanced Catalysis Technology Laboratory School of Chemical Sciences and Food Technology Faculty of Science and Technology Universiti Kebangsaan Malaysia Bangi 43600 Malaysia

Esterification of acrylic acid（AA） to produce AA esters has widespread application in the chemical industry. A series of water tolerant solid acid catalysts was prepared, and characterized by XRD, nitrogen adsorption, TGA-DTA, XPS, and ammonia adsorption FTIR. The effects of Si/Al ratio, zirconium sulfate（ZS） loading on HZSM-5 and calcination temperature on the esterification were investigated. When 20% （mass fraction） ZS is loaded on HZSM-5, the conversion of AA reaches 100%. XRD analysis indicates that ZS is highly dispersed on HZSM-5 because no crystalline structure assigned to ZS is found. Catalytic activity and hydrophobicity of ZS supported on HZSM-5 are higher compared with those of parent ZS or HZSM-5. Results show that this kind of novel catalysts is an efficient water tolerant solid acid catalyst for esterification reactions.

关键词： Solid acid catalyst Zirconium sulfate HZSM-5 Esterification reaction Water tolerant

Electronic Structure Effect of Polythiophene Derivatives and Nano N-Zn-Ag/TiO2 on Performance of Organic Thin Film Solar Cell

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Chemical Research in Chinese Universities 2013年第5期29卷 998-1002页

作者： ZHANG Jing-chang WEN Yu LI Qi-yun HAN Zhi-yue FU Zhen-hai cao wei-liang State Key Laboratory of Chemical Resource Engineering Institute of Modern Catalysis Beijing University of Chemical Technology Beijing 100029 P. R. China Hainan Institute of Science and Technology Haikou 571126 P. R. China

Nanocrystal N-Zn-Ag/TiO2 powders were prepared with N-Zn/TiO2 by photo deposition method. A series of pure polymers P3HT[poly（3-hexylthiophene）], P3OT[poly（3-octylthiophene）], P3DT[poly（3-decylthiophene）] and P3DDT[poly（3-dodecylthiophene）], was synthesized, which were used to synthesize p-n type semiconductor mate- rials P3HT/N-Zn-Ag-TiO2, P3OT/N-Zn-Ag-TiO2, P3DT/N-Zn-Ag-TiO2 and P3DDT/N-Zn-Ag-TiO2 by in situ che- mical method. X-Ray diffraction（XRD） and infrared（IR） spectroscopy showed the structure of the polymers and complexes. Ultraviolet-visible（UV-Vis） spectra and cyclic voltammograms（CV） showed the optical and electronic performance of the polymers and complexes. Two new single and double organic thin film heterojunction solar cells were prepared with the above mentioned synthesized powders as raw materials. Current-voltage（I-V） measurements indicate that the conversion efficiency of the single organic thin film heterojunction solar cell is higher than that of the double organic thin film heterojunction solar cells. Single organic thin film heterojunction solar cells based on P3DT/N-Zn-Ag-TiO2 can get a photoelectric conversion efficiency of 0.0408%. The performance of electronic trans- form between electron donor and acceptor on organic thin film solar cells was researched.

关键词： N-Zn/TiO2 N-Zn-Ag/TiO2 Poly(3-decylthiophene) Electronic structure Organic thin film heterojunctionsolar cell

Treatment on the electronic energy bands of the helix-symmetrical polymers（n1）by Lcao/TO—LCTO/HO—LCHO/PO

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Chinese Journal of Chemistry 1985年第3期3卷 181-193页

作者： WANG Zou-Xin cao wei-liang Department of Chemical Engineering,Beijing Institute of Chemical Technology,Beijing Department of Chemical Engineering Beijing Institute of Chemical Technology Beijing

Helix-Symmetrical polymer possesses not only translation symmetry but also *** the basis of this kind of symmetry,a new linear combination method named as Lcao/To-LCTO/HO-LCHO/PO has been established to derive the secular equation for this kind of *** such a manner,the order of secular equations can be reduced from n×P to P（where n isthe number of atomic orbitals in each translational unit,and P is the same number but in eachhelical unit）,thus cbtaining the maximum factorization of the secular equations and favoring thesymmetrical analysis of the *** computational program corresponding to the EHMOscheme was edited for calculating the helix-symmetrical *** principle,this treatment can be applied to the other quantum chemistry *** and polyacetylene as examples,the energy bands with 21,31and 41helical comformationswere calculated by the computional *** discussions on the influence of the variation ofcomformations to energy bands and the related physical and chemical properties were given.

关键词： Treatment on the electronic energy bands of the helix-symmetrical polymers LCHO/PO