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Synthesis and kinetics of 2-chloro-4,6-dinitroresorcinol

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Journal of Harbin Institute of Technology(New Series) 2008年第4期15卷 518-520页

作者：史瑞欣黄玉东 dept.of chemistry and Chemical Engineering Northeast Forestry University dept.of Applied chemistry Harbin Institute of Technology

2-chloro-4,6-dinitroresorcinol was synthesized from 4,6-dinitro-1,2,3-trichlorobenzene by *** ultraviolet spectrophotometry was used to measure the absorbency of the hydrolysis mixture under different temperatures and periods of *** kinetic calculation,it is shown that when the reaction temperature is in the range of 343.15 K to 358.15 K,the reaction is consistent with the secondary apparent dynamic model,the apparent activation energy is 200.11 kJ/mol and the expression of kinetic parameter k is 3.761×1028exp(-2.001×105/RT).The reaction is controlled by the course of chemical reactions.

关键词：化工动力学 2-氯-4,6-二硝基间苯二酚合成方法动力学

DFT studies on the SCR reaction mechanism of nitrogen monoxide with propylene catalyzed by copper oxide

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Journal of Harbin Institute of Technology(New Series) 2007年第3期14卷 389-391页

作者：田英许晶赵景祥 dept.of chemistry Harbin Normal University

The SCR reaction mechanism of NO with C3H6catalyzed by CuO was studied by the method of Density Functional Theory(DFT)at the B3LYP/LanL2DZ *** optimized geometries of the stationary points on the potential surface were obtained and the transition state was confirmed by IRC and vibration *** activation energy was calculated being 34.26 kJ/*** was shown that propylene reacted firstly with Cu forming intermediate,and then nitrogen monoxide immediately reacted with the intermediate to be *** was proved to be a direct interaction mechanism.

关键词：氧化铜催化反应一氧化氮丙烯反应机理密度泛函理论选择性催化还原

AN AB INITIO N_(2)-H_(2)O POTENTIAL FOR COMPUTER SIMULATIONS

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Chinese Chemical Letters 1995年第2期6卷 169-172页

作者： Jian De GU Jing Lai ZHANG An Min TIAN Guo Sen YAN chemistry dept.of Sichuan University Chengdu 610064

N2-H2O system was studied by ab initio SCF calculations with a 6-31G** basis set. The results were fitted to an analytical funotion assuming psirwise additivity for the interaction between individual centres. The analytical functions were Lennard-Jones 10-6 and exponential form. A satisfactory fitting result was achieved by the simulated anneal algorithm. Special care was paid to repulsive region, which gives the important contribotions to the formation of the first solvation shell of apoler solutes.

关键词： ?

Crystallization process of 2-chloro-4,6-diaminoresorcinol

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Journal of Harbin Institute of Technology(New Series) 2009年第4期16卷 532-536页

作者：宋元军黄玉东林宏黎俊王卓 dept.of Applied chemistry Harbin Institute of Technology

In order to get 2-chloro-4,6-dinitroresocinol(CDNR) with high purity,which influences the synthesis of 4,6-diaminoresorcinol dihydrochloride,the solubility of CDNR in various solvents was measured by laser method and ethanol was chosen as the *** recrystallization process of CDNR was investigated and crystallizing parameters such as cooling rate,temperature and time were *** results show that the time and temperature of crystallization greatly affect the yield and a higher yield can be received at-8 ℃ for 5 *** cooling rate is helpful to the crystallization of CDNR,and the mechanical stirring or ultrasonic treatment can increase the yield and the purity of CDNR.

关键词：结晶过程间苯二酚二氨基氯时间参数结晶温度冷却速度结晶速率

Preparation of superabsorbent by graft copolymerization of acrylic acid onto corn starch using K_2S_2O_8 and rare earths as initiators

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Journal of Harbin Institute of Technology(New Series) 2008年第6期15卷 831-834页

作者：白永平李卫东冯立群赵超 dept.of Applied chemistry Harbin Institute of Technology

K2S2O8 and rare earths(RE)were used as initiators to prepare superabsorbents by graft copolymerization of acrylic acid(AA)onto corn *** effects of monomer concentration,initiator K2S2O8 concentration,cross-linker concentration,reaction temperature and the concentration ratio of RE and K2S2O8 on the graft copolymerization were studied in terms of the water absorption capacity of *** indicate that the optimum conditions obtained for the grafting of AA onto 5g starch are as follows:AA of 75.773 g/L,K2S2O8 of 0.437 g/L,RE of 0.874 g/L,cross-linker of 0.381 g/L and temperature of 70 ℃.The maximum water absorption capacity obtained is 740 g/*** new method of graft polymerization is easily proceeded and *** graft copolymers were characterized by infra-red spectroscopy,scanning electron microscopy and *** characterized by IR and SEM give strong evidence for grafting of AA onto corn starch,and those characterized by TG reveal that the grafting of AA improves the thermostability of corn starch.

关键词：超吸收剂共聚合淀粉丙烯酸

Paederia foetida- a promising ethno-medicinal tribal plant of northeastern India

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Journal of Forestry Research 2013年第4期24卷 801-808页

作者： Silpi Chandadept.of Pharmacy Jaypee University of Information Technology Indira P Sarethy Biplab De Kuldeep Singh dept.of Biotechnology Jaypee Institute of Information Technology dept.of Pharmaceutical Science Assam University dept.of Pharmacy Jaypee University of Information Technology

The northeastern region of India constitutes one of the biodi- versity hotspots of the world. The ethnic groups inhabiting this region practice their distinctive traditional knowledge systems using biodiver- sity for food, shelter and healthcare. Among the less-studied plants, Paederia foetida has been used by various ethnic tribes as food and medicine. Many of its therapeutic properties relate to the gastrointestinal system and suggest its potential utility for gastrointestinal ailments. This is a review of the ethnobotanical uses, phytochemistry and therapeutic properties of P. foetida compiled from various reports. P. foetida is promising as a remedy for life-style related conditions, especially treat- ment of ulcers. Its utility highlights the need for proper evaluation of tribal plants as medicines and the species could be considered for devel- opment of new drugs.

关键词： Paederia foetida Tribal medicine ethnobotany phyto-chemistry therapeutic ulcer

Synthesis,Characterization and Crystal Structure of a Three-dimensional Coordination Polymer {[Cd(1,5-nds)(Him)_2(H_2O)]·2H_2O}n

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Chinese Journal of Structural chemistry 2008年第12期27卷 1533-1537页

作者：钱保华马卫兴许兴友陆路德杨绪杰汪信 Materials chemistry Laboratory Nanjing University of Science & Technology dept.of Chemical Technology Huaihai Institute of Technology

A novel cadmium（Ⅱ） coordination polymer {[Cd（1,5-nds）（Him）2（H2O）]·2H2O}n （1,5-nds = naphthalene-1,5-disulfonate and Him = imidazole） was synthesized based on the reaction of cadmium oxide and 1,5-naphthalenedisulfonic acid firstly, and then mixed with imidazole in methanol medium. Its structure was characterized by elemental analysis, IR and TGA, respectively. The crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1, with a = 8.5420（10）, b = 10.2570（10）, c = 13.361（2） A, α = 100.704 （2）, β = 100.195（2）, γ = 108.873（3）°, C16H20Cd N4O9S2, Mr= 588.91, V = 1.0524（2） nm^3, Dc = 1.858 g/cm^3, Z = 2, F（000） = 592, β^ = 1.294 mm-1, R = 0.0397 and wR = 0.1007 for 3180 observed reflections （Ⅰ〉 2σ（Ⅰ））. Structural analysis shows that the cadmiun atom is coordinated with four oxygen atoms from three 1,5-nds and one water molecule together with two nitrogen atoms from two imidazoles, giving a distorted octahedral coordination geometry. The molecules are linked to form a two-dimensional coordination polymer based on bridging ligands of naphthalene- 1,5-disulfonate anions, the sheets of which are then interacted via hydrogen bonds, leading to a three-dimensional network structure.

关键词： cadmium(Ⅱ) coordination polymer crystal structure naphthalene-1,5-disulfonate anion imidazole

Role of asymmetry effect on the specific conductivity of water——A case study

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Chinese Journal Of Geochemistry 2012年第3期31卷 276-281页

作者： Parameswara D. Prasad K.S.S. dept.of chemistry S.G.S.Arts CollegeTirupatiIndia dept.of Geology S.V.UniversityTirupatiIndia

Forty-one water samples in each season(both pre-and post-monsoon) were collected from different for-mations of the Kadiri schist belt located in the Anantapur district,Andhra *** specific electrical conductiv-ity(EC) of these water samples was measured at 25℃ by using specific conductivity *** specific conductiv-ity values of the water samples were also calculated by multiplying ionic concentrations with conductivity *** is found that the observed EC values of all water samples collected in both the seasons are different from the esti-mated EC values because of the electro-chemical properties of ions in water.

关键词：水样电导率不对称案例 EC值导热系数离子浓度化学性质

Artificial network prediction on degradable properties of coal-filled films

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Journal of Coal Science & Engineering(China) 2005年第2期11卷 78-81页

作者：杨志远周安宁曲建林 dept.of Material Science and Technology Xi’an University of Science & TechnologyXi’an 710054China dept.of chemistry and Chemical Engineering Xi’an University of Science & TechnologyXi’an 710054 China2 dept.of chemistry and Chemical Engineering Xi’an University of Science & TechnologyXi’an 710054 China

Utilized degradable data of coal-filled films from the accelerated UV chamber ageing degradation experiments, and on the basis of control factors’ analysis, presented a predicting model on degradable properties of this film in photo-degradation according to back-propagation artificial neural network (BP ANN). 4 controlling factors in films degrada-tion, including temperature, the time of UV irradiation, the concentration and the type of coals were used as input parameters in the ANN model. While the degradable properties after film degradation, including the mechanical properties and carbonyl index, were used as output parameters. It was carried out by the neural network toolbox of Matlab 6.5 soft-ware and Visual Basic 6.0. Discussed partition of sample data and model’s parameters, and then selected the best configuration of ANN network. The accurate scope of predicting results was analyzed. This model has a high precision in predicting on properties of the coal-filled film degradation.

关键词：薄煤层预报方法人工神经网络降解性能模型参数