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Numerical Modeling of NO Formation during Packed-bed Combustion of Coke Granules

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 261-268页

作者： Chunbao Xu, Shengli Wu, Daqiang Cang (Metallurgy school, university of science and technology Beijing, Beijing 100083, china Institute for chemical Reaction science, Tohoku university, Japan) Metallurgy school University of Science and Technology Beijing Beijing 100083 China Institute for chemical Reaction science Tohoku University Japan

A comprehensive kinetic model of NO formation during coke combustion in packed-bed in presence of noncombustible particles was developed. The detailed homogeneous gas-phase chemistry (including 102 chemical reactions), heterogeneous gas-solid chemistry (including 11 reactions) of coke combustion and NO formation, and the heat and mass transfer were taken into account in the present model. The governing equations which are strongly coupled, non-linear and unsteady with 26 unknowns in total, were dispersed into differential equations with the finite differential method. Meanwhile, all the differential equations were numerically solved to give the time-histories and space-distributions oftemperatures of the bed and gas phase as well as the concentrations of all the gaseous species. By comparison, the experimental data were explained well by the calculated results. Based on the kinetic and mathematical model, the effects of O2 content of inlet gas, the initial chemical analysis of coke, bed-temperature and local reductive atmosphere (CO/O2) on NO formation during packed-bed coke combustion were numerically discussed. It was found that coke samples with a higher initial content of [N] and volatile matters, combusted under a suitable O2-containing atmosphere produced less NO emission. The reactions between CO and NO, catalyzed by high temperature surface of coke particles may be responsible for efficient reduction of NO.

关键词： kinetic model NO formation combustion packed-bed coke Metallurgy

An efficient chiral synthesis of (R)-N-[3-acetyl-4-(2-hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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science china chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2 & TANG XinLiang1,3 1 Technical Institute of Physics and chemistry,Chinese Academy of sciences,Beijing 100080,china 2 College of chemistry and chemical engineering,Graduate university of Chinese Academy of sciences,Beijing 100049,china 3 school of chemical engineering and Environment,Beijing Institute of technology,Beijing 100081,china 1. Technical Institute of Physics and chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of chemistry and chemical engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. school of chemical engineering and Environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2-hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

Oxygen Permeability of Polypropylene Containing Polyisobutene with Magnesium Acetate

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 118-121页

作者： Wei Tian Raymond T. Woodhams(Material science and engineering school, university of science and technology Beijing, Beijing 100083, china)(Dept. of chemical engineering and Applied chemistry, university of Toronto, Torono M5S IA4, Canada) Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Univ Toronto Dept Chem Engn & Appl Chem Toronto ON M5S 1A4 Canada

The oxygen permeabilities of polypropylene films are reduced by adding a minor percentage of a polyisobutene ionomer. The polyisobutene ionomers were prepared by in situ salt exchange of magnesium acetate with maleated polyisobutenes of commercially available low relative molecular mass. The more polar magnesiurn salts aided phase separaion during crystallization from the molten polypropylene mixtusre. Scanning electron microscope photographs revealed that the polyisobotene ionomer is largely concentratd in the amorphous regions between the polypropylene spherulites, where the ionomer tends to concentrate during crystallization. The influence of the polyisobutene ionomer on the oxygen permeability of polypropylene was found to be slightly dependent upon the relative molecular mass of the polyisobutene precursor. Under optimum conditions, the oxygen permeability of polypropylene is reduced by 20%with only 1% additive.

关键词： oxygen permeability polypropylene polyisobutene

X-ray and Magnetoresistance Measurements of Electrodeposited Cu-Co Granular Films

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Journal of Materials science & technology 2005年第3期21卷 307-310页

作者： Suwei YAO, Haixia WU, Weiguo ZHANG and Hongzhi WANG Sugiyama Laboratory of Surface technology, Department of Applied chemistry, school of chemical engineering and technology, Tianjin university, Tianjin 300072, china Department of Applied chemistry School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

Granular CoxCu1-x alloy films were prepared by electrodeposition at room temperature directly onto semiconducting Si substrate. X-ray diffraction (XRD) revealed that the as-deposited films formed single phase metastable fcc alloy structure. The fcc lattice parameter α was found to decrease linearly with increasing Co concentration x in the studied range. The giant magnetoresistance (GMR) of the films was improved after annealing. Pure Co fcc diffraction peaks were observed in the diffractogram of the annealed sample, indicating phase separation occurred upon annealing. The optimal annealing temperature was 450℃. The maximum of magnetoresistance (MR) ratio 8.21% was obtained for the Co20Cu80 thin film after annealing at 450℃ for 1 h. The saturation field decreased upon annealing in the MR curves of Co20Cu80 film.

关键词： Electrodeposition Giant magnetoresistance (GMR) Granular Phase separation

chemical Extraction Preparation of Delithiated Cathode Materials of Li-ion Battery

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Journal of Wuhan university of technology(Materials science) 2009年第6期24卷 863-866页

作者：闫时建 school of Materials science and engineering Taiyuan University of Science and Technology

A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2S2O8 in water solution, and the solution was stirred continuously to make the chemical reaction proceed sufficiently, then the reaction product was filtered and finally the insoluble delithiated cathode material was obtained. A series of tests were conducted to verify the composition, crystal structure and electrochemical property of the delithiated cathode materials were all desirable. This method overcomes the shortcomings of battery charging preparation and chemical extraction preparation employing other oxidizing agents.

关键词： chemical extraction delithiated cathode material Li-ion battery

Sensing characterization of Sn/In/Ti nanocomplex oxides for CO, CH_4 and NO_2

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science china(Technological sciences) 2007年第1期50卷 18-26页

作者： BAI ShouLi1, TONG ZhangFa2, LI DianQing1, HUANG XiaoWei3, LUO RuiXian1 & CHEN AiFan1 1 State Key Laboratory of chemical Resource engineering, Beijing university of chemical technology, Beijing 100029, china 2 school of chemistry and chemical engineering, Guangxi university, Nanning 530004, china 3 College of Biochemical engineering, Beijing Union university, Beijing 100023, china 1. State Key Laboratory of chemical Resource engineering Beijing University of Chemical Technology Beijing 100029 China 2. school of chemistry and chemical engineering Guangxi University Nanning 530004 China 3. College of Biochemical engineering Beijing Union University Beijing 100023 China

The nanocomplex oxides of Sn-In and Sn-In-Ti were prepared by controlled co-precipitation method as sensing materials of semiconductor gas sensors for detection of CO, CH4 and NO2. Through manipulating the Sn/In cation ratio, metal salt total concentration, precipitation pH value and aging time, the nanocrystalline powders were successfully derived with chemical homogeneity and superior thermal stability, compared with the single component oxides. The particle size and morphology, surface area, and thermal and phase stabilities were characterized using TEM, TG-DTA, BET and XRD. The sensing tests showed that the Sn-In com-posites exhibit high sensitivity and selectivity for CO and NO2. The introduction of TiO2 enhanced CH4 sensitivity and selectivity, particularly, additives of Pd and Al2O3 as a dopant and surface modification greatly enhanced the sensing properties. The sensitivity depended on the composition of composites, calcination temperature and operating temperature. The optimal values were (25%In2O3- 75%SnO2)-20%TiO2 for ternary composite, 600 and 300℃, respectively. Temperature-programmed de-sorption (TPD) studies were employed to explain the gas adsorption behavior dis-played by the surface of nanocomposites and X-ray photoelectron spectroscopic (XPS) analysis was used to confirm the electronic interactions existing between oxide components. The sensing mechanism of the nanocomposites was attributed to chemical and electronic synergistic effects.

关键词： SnO2-In2O3-TiO2 nanocomposites CO NO2 CH4 gas sensing

A contribution to the study of the modified Marschalk reaction:Hydroxymethylation of 6,8-O-dimethyl emodin

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Chinese chemical Letters 2010年第5期21卷 568-571页

作者： Hai Shan Jin,Li Ming Zhao school of chemistry and chemical engineering,Xuzhou Normal university,Xuzhou 221116,china [a] school of chemistry chemical engineering Xuzhou Normal University Xuzhou 221116 China

Hydroxymethylation of 6,8-O-dimethyl emodin was easily achieved in good yields by the modified Marschalk *** influence of the amount of solvent,base and formaldehyde toward the hydroxymethylation was *** results showed that a relatively dilute reaction solution facilitated the generation of the desired 2-hydromethyl product,while the thick reaction solution benefited the generation of the methylated quinizarins.

关键词： Marschalk reaction Hydroxymethylation Emodin Antitumor activity

Development of Multi-Wavelength Spectral-Correction Method

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Chinese chemical Letters 2000年第10期11卷 893-894页

作者： Hong Wen GAO (school of chemistry and chemical engineering, Anhui university, Hefei 230039) Anhui Univ Sch Chem & Chem Engn Hefei 230039 Peoples R China

This investigation developed a new method for determining metal complex's property containing the stepwise real absorptivity(epsilon) and stability constant (K-m). The correction equation of the multi-wavelength spectral absorption was established for the simultaneous determination of various complexes to give high accuracy for trace analysis. This method was more acceptable in theory and simpler in operation than the classical methods.

关键词： simultaneous determination multi-wavelength spectral-correction complex property

Theoretical studies on the possible conformers and properties of tetranitrodiazidoacetylhexaazaisowurtzitane (TNDAIW)

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science china chemistry 2004年第5期47卷 414-419页

作者： WU Yukai1, OU Yuxiang1, LIU Zhiguo1,2 , LIU Jinquan1, MENG Zheng1 & CHEN Boren1 1. school of Materials science and engineering, Beijing Institute of technology, Beijing 100081, china 2. school of chemistry and chemical engineering, Henan university, Kaifeng 475001, china 1. school of Materials science and engineering Beijing Institute of Technology 100081 Beijing China 2. school of chemistry and chemical engineering Henan University 475001 Kaifeng China

Tetranitrodiazidoacetylhexaazaisowurtzitane (TNDAIW) is a novel polyazapolycyclic caged polyazidonitramine explosive first synthesized in our laboratory. All of the possible con- formers of TNDAIW are optimized using both the AM1 and PM3 methods. TNDAIW is predicted to have more polymorphs than hexanitrohexaazoisowurtzitane (CL-20). The HF/6-31G(d) level of theory is used to investigate the lowest energy structures of D-TNDAIW for both AM1 and PM3. The possible conformers of TNDAIW are predicted to be more stable than epsilon-CL-20 based on the N-NO2 bond lengths. The impact and shock sensitivities of both the possible DA- and DP-TNDAIW are lower than the corresponding ones of epsilon-CL-20. TNDAIW with the possible conformers is estimated to be a promising novel high energy density explosive.

关键词： tetranitrodiazidoacetylhexaazaisowurtzitane, molecular modeling, impact and shock sensitivities.