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Thermal Decomposition Kinetics and Mechanism of Tb(Ⅲ) m-Methylbenzoate Complex with 1,10-Phenanthroline in Static Air Atmosphere

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Chemical Research in Chinese Universities 2002年第1期18卷 25-29页

作者： zhang jian-jun WANG Rui-fen zhang jian-ling WANG Shu-ping Experimental Center Hebei Normal UniversityShijiazhuang 050016P.R.China Department of Chemistry Hebei Normal UniversityShijiazhuang 050091.P.R.China Institute of Chemistry Chinese Academy of SciencesBeijing 100080P.R.China

The thermal behavior of [Tb_2( m -MBA)_6(phen)_2](H_2O)_2( m -MBA=C_8H_7O_2, methoxybenzoate; phen=C_ 12 H_8N_2, 1,10-phenanthroline) in static air atmosphere was investigated by means of TG-DTG and DTA methods. The thermal decomposition of the title compound takes place mainly in two steps. The intermediate and the residue for each decomposition were identified by the TG curve. By the kinetic method of processing thermal analysis data put forward by Malek et al ., it is defined that the kinetics model for the first-step thermal decomposition is SB( m,n ).

关键词： Thermal decomposition Non-isothermal kinetics Tb(Ⅲ) complex m-Methylbenzoate 1,10-Phenanthroline

Broadband channel measurement and analysis

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 24-28页

作者： zhang Ming zhang jian-hua jianG jun zhang Ping WU Yu-fei Wireless Technology Innovation Labs (WTI) Beijing University of Posts and Telecommunications Beijing 100876 China

An outdoor propagation measurement campaign for beyond 3G （B3G） as well as a wide-band indoor measurement campaign have been performed recently in Beijing, China, in which the sounding signals are transmitted by an one-antenna base station and received by a two-antenna mobile receiver operated at 3.49～3.51 GHz bandwidth. Different scenarios： stationary line-of-sight （LoS）, stationary non-LoS （NLoS） scenarios, and dynamic NLoS are deliberately chosen in a classic urban environment and office environment. The initial results are presented in this article. Parameters including vector channel impulse response, path loss, rays number, excess delay spread etc. are extracted, analyzed, and briefly reported here.

关键词： Broadband measurement Beyond 3G path loss,multipath delay rays number

Preparation, Crystal Structure and Thermal Decomposition Process of Dysprosium Benzoate Complex with 1,10-Phenanthroline

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Chinese Journal of Structural Chemistry 2008年第2期27卷 233-237页

作者： XU Su-Ling zhang jian-jun REN Ning zhang Hai-Yan HU Rui-Sheng Experimental Center Hebei Normal UJziversity Shijiazhuang 050016 China Department of Engineering Shijiazhuang Foreign Economy and Trade Vocational College Shijiazhuang 050061 China Department of Chemistry Handan College Handan 056005 China School of Chemical Engineering Shijiazhuang College Shijiazhuang 050035 China

A dinuclear dysprosium（III） complex with benzoic acid and 1,10-phenanthroline, [Dy（BA）3phen]2 （BA = benzoate, PHEN = 1,10-phenanthroline）（C66H46Dy2NaO12, Mr = 1412.07） was synthesized and characterized by elemental analysis, UV, IR, X-ray diffraction, molar conductance and TG-DTG techniques. It crystallizes in triclinic, space group P1 with a = 10.773（2）, b = 11.933（3）, c = 12.417（5） A, α= 105.226（3）,β= 93.470（3）, γ= 113.475（2）°, V= 1388.0（7）, Z = 1, Dc = 1.689 g/cm3, μ（MoKa） = 2.742 mm-1 and F（000） = 698. R = 0.0210, wR = 0.0538. In the crystal, each Dy（III） ion is eight-coordinated by one bidentate chelating carboxylate group, four bidentate bridging carboxylate groups and one 1,10-phenanthroline molecule. The thermal decomposition process of [Dy（BA）3phen]2 has been determined by thermal analysis.

关键词： benzoic acid crystal structure 1,10-phenanthroline dysprosium complex thermal analysis

Seasonal variations in the influence of vegetation cover on soil water on the loess hillslope

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Journal of Mountain Science 2020年第9期17卷 2148-2160页

作者： SHEN Ming-shuang zhang jian-jun zhang Shou-hong zhang Hai-bo SUN Ruo-xiu zhang Yi-zhou School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China National Station for Forest Ecosystem Research in Ji County Ji County 042200Shanxi ProvinceChina

Soil water is the key factor that restricts the restoration of the local ecological systems in the Loess Plateau of *** the effects of vegetation types on soil water and its seasonal variation helps to understand hydrological characteristics and provides insights into the sustainable restoration of ***,the Caijiachuan watershed was chosen as the research object to investigate the water status of a 0-10 m soil layer under different vegetation types including Pinus tabulaeformis,Robinia pseudoacacia,Platycladus orientalis,apple orchard,natural forestland,farmland and *** comparing the difference between soil water of different land use types and that of grassland during the same period,the seasonal changes of soil water status of different types were *** results show that(1)in the 0-10 m soil layer,the largest value of soil water content was in the0.3-0.4 m layer,and the lowest was in the 5.6-5.8 m *** depths at which the vegetation cover influenced the soil water were up to 10 m;(2)among summer,fall and spring,the soil water storage wasthe highest in the *** addition,the lowest value of relative accumulation was in the fall,which was the period in which the soil water recovered;(3)the soil water in the 0-10 m layer was in a relatively deficient state in the artificial forestlands,apple orchards and native forestlands,while the relative accumulation was in the *** addition,the relative deep soil layers(8-10 m)had more serious deficits in the areas in which ***,*** and the apple orchard grew;(4)during the study period,the farmland in the summer had the largest relative accumulation(182.71 mm),and the land under *** in the fall had the lowest relative deficit(512.20 mm).In the Loess Plateau,vegetation cover will affect the change of deep soil moisture and artificial forest will cause soil water loss in different degrees.

关键词： Seasonal variation Soil water Vegetation cover Hillslope Loess Plateau

Effects of Carrier Gas on Carbon Incorporation in GaN

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Chinese Physics Letters 2014年第3期31卷 122-124页

作者： zhang jian-Li LIU jun-Lin PU Yong FANG Wen-Qing zhang Meng jianG Feng-Yi National Engineering and Technology Research Center for LED on Si Substrate Nanchang University Nanchang 330047

GaN epitaxial layers were grown on Si （111） substrates by metal organic chemical vapor deposition. Carbon concentrations in the films grown in different ambients were measured by secondary ion mass spectrometry. The results show that the carbon incorporation is strongly dependent on the H2 flow rate when the NH3 flow rate is small, but insensitive to the H2 flow rate when the NH3 flow rate is sufficient large. We conclude that H2 can inhibit the dissociation of NH3 and result in a less active N source; an insufficiently active N source causes more N vacancies, which enhances carbon incorporation.

关键词： Gallium nitride

An improved method of potential of mean force for protein-protein interactions

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Chinese Science Bulletin 2008年第8期53卷 1145-1151页

作者： SU Yux LI WenFei zhang jian WANG jun WANG Wei National Laboratory of Solid State Microstructure and Department of Physics Nanjing University Nanjing 210093 China

In this work, the traditional method of potential of mean force (PMF) is improved for describing the protein-protein interactions. This method is developed at atomic level and is distance-dependent. Compared with the traditional method, our model can reasonably consider the effects of the environ- mental factors. With this modification, we can obtain more reasonable and accurate pair potentials, which are the pre-requisite for precisely describing the protein-protein interactions and can help us to recognize the interaction rules of residues in protein systems. Our method can also be applied to other fields of protein science, e.g., protein fold recognition, structure prediction and prediction of thermo- stability.

关键词：基础知识 PMF 双蛋白交互作用

Simulation of water and nitrogen dynamics as affected by drip fertigation strategies

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Journal of Integrative Agriculture 2015年第12期14卷 2434-2445页

作者： zhang jian-jun LI Jiu-sheng ZHAO Bing-qiang LI Yan-ting Institute of Agricultural Resource and Regional Planning Chinese Academy of Agricultural Sciences State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research

The aim of drip fertigation is synchronising the application of water and nutrients with crop requirements, and maintaining the proper concentration and distribution of nutrient and water in the soil. The wetting patterns and nutrient distributions under drip fertigation have been proved to be closely related to the fertigation strategies. In order to find out the critical factors that affect the nutrient distribution under different drip fertigaiton strategies, a computer simulation model HYDRUS2D/3D was used to simulate the water and nitrate distribution for various fertigation strategies from a surface point source. Simulation results were compared with the observed ones from our previous studies. A 15° wedge-shaped plexiglass container was used in our experiment to represent one-twenty-fourth of the complete cylinder. The height of container is 40 cm, and the radius is 41 cm. The ammonium nitrate solution was added through a no. 7 needle connected to a Mariotte tube with a flexible hose. The soil water content, nitrate and ammonium concentrations were measured. The comparison of simulated and observed data demonstrated that the model performed reliably. The numerical analysis for various fertigation strategies from a surface point source showed that：（1） The total amount of irrigation water, the concentration of the fertilizer solution and the amount of pure water used to flush the pipeline after fertilizer solution application are the three critical factors influencing the distribution of water and fertilizer nitrogen in the soil.（2） The fresh water irrigation duration prior to fertigation has no obvious effect on nitrate distribution. The longer flushing time period after fertigation resulted in nitrate accumulation closer to the wetting front. From the point of avoiding the possibility of nitrate loss from the root zone, we recommended that the flushing time period should be as shorter as possible.（3） For a given amount of fertilizer, higher concentration of t

关键词： fertigation strategy drip irrigation modelling nitrate transport

Clinical significance of combined determination of serum PGⅠ , PGⅡ and GAS for diagnosis of gastric cancer

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Nuclear Science and Techniques 2005年第4期16卷 217-220页

作者： jianG Meng-jun LI Wen-Xin XIAO Zhi-jian zhang Rong-jun CAI Gang-Ming State Key Laboratory of Nuclear Medicine Jiangsu Institute of Nuclear Medicine. Wuxi 214063

To evaluate the clinical value of combined determination of serum PGⅠ, PGⅡ and GAS for early diag-nosis of gastric cancer, the serum levels of PGⅠ, PGⅡ and GAS in 190 healthy controls and 129 patients with gas-tric disorders were measured by RIA. The 129 patients include 68 cases of gastric cancer. The results showed that the serum levels of PGⅠ and PGⅠ/PGⅡ ratio in gastric cancer patients were obviously lower than those in healthy controls, while comparing with controls, the serum GAS levels were significantly higher. The diagnostic accuracy of the determinations for gastric cancer was evaluated by receiver operating characteristic (ROC) curve analysis. The area under the curve (AUC) levels of serum PGⅠ, PGⅠ/PGⅡ ratio and GAS were 0.833, 0.842 and 0.851, respec-tively. As serum PGⅠ or PGⅠ/PGⅡ ratio or GAS were combined, the sensitivity and specificity of determination for gastric cancer diagnosis were 94.2% and 73.4%, respectively. All these results indicated that the combined deter-mination of serum PGⅠ, PGⅡ and GAS levels may be used as a tool for primary screening of gastric cancer.

关键词：免疫血清诊断方法胃癌放射性疗法实验室诊断放射性同位素

Nonisothermal Kinetics of Dehydration Process of [Sm(m-ClBA)_3phen]_2·2H_2O and [Sm(p-ClBA)_3phen]_2·2H_2O

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Chemical Research in Chinese Universities 2008年第2期24卷 210-214页

作者： REN Ning WANG Xi-e zhang Jie zhang jian-jun XU Su-ling zhang Hai-yan Experimental Center Hebei Normal University Shijiazhuang 050016 P. R. China Department of Chemistry Handan College Handan 056005 P. R. China Zhengding High School of Hebei Zhengding 050800 P R China Aino Co. Ltd. of North China Pharmaceutical Group ShO＇iazhuang 052165 P. R. China

Compounds [Sm（m-CIBA）3phen]2.2H20 and [Sm（p-CIBA）3phen]2·2H20（m-CIBA=m-chlorobenzoate, pClBA=p-chlorobenzoate, phen=l,10-phenanthroline） were prepared. The dehydration processes and kinetics of these compounds were studied from the analysis of the DSC curves using a method of processing the data of thermal analysis kinetics. The Arrhenius equation for the dehydration process can be expressed as lnk=-38.65-243.90×l0^3/RT for [Sm（m-CIBA）3phen]2·2H2O, and lnk=38.70-172.22×103/RT for [Sm（p-CIBA）3phen]2·2H2O. The values of △H^1, △G^1, and △S^1 of dehydration reaction for the title comnonnds are determined respectively.

关键词： Dehydration DSC m-Chlorobenzoate Nonisothermal kinetics p-Chlorobenzoate 1,10-Phenanthroline Samarium complex