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Synthesis and Crystal Structure of Binuclear Silver(I) Complex with 2-nitro-(2-pyridylsulfanylmethyl)benzene

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Chinese Journal of Structural Chemistry 2005年第11期24卷 1306-1309页

作者： song Rui-feng Department of Chemistry and Chemical Engineering University of Science and Technology of Suzhou Suzhou 215009 China

The reaction of 2-nitro-（2-pyridylsulfanylmethyl）benzene L with silver nitrate produces a centrosymmetric binuclear complex bis（2-nitro-（2-pyridylsulfanylmethyl）benzene-N,S）- bis（nitrato-O,O）-disilver（Ⅰ）, [AgLNO3]2 1. The crystal is of triclinic, space group PI, with a = 7.383 （3）, b = 8.340（3）, c = 12..003（4） A, a = 95.069（6）, β = 93.498（5）, γ = 102.734（6）°, C24H20Ag2N6- O10S2, Mr= 832.32, V = 715.6（4） ,A^3, Z = 1, Dc = 1.931 g/cm^3, F（000） = 412,μ = 1.581 mm^-1, R= 0.0351 and wR = 0.0749 Each silver atom is tetrahedrally coordinated by two O atoms from bidentate nitrate, one S atom from a ligand and one N atom from another ligand. Furthermore, Ag- Ag interactions have been observed in the complex.

关键词： silver(Ⅰ) complex 2-nitro-(2-pyridylsulfanylmethyl)benzene crystal structure,Ag-Ag interactions

Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi Wang Jun-Lei Yin Xing-Yu Gao Shu-feng Yang Hai-feng song Jin-Shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

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Tool wear criterion,tool life,and surface roughness during high-speed end milling Ti-6Al-4V alloy

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第8期11卷 587-595页

作者： song ZHANG Jian-feng LI MOE Key Laboratory of High Efficiency and Clean Mechanical Manufacture School of Mechanical Engineering Shandong University Jinan 250061 China

The objective of the present research is to investigate the relationship among tool wear, surface topography, and surface roughness when high-speed end milling Ti-6Al-4V alloy, and also to define an optimal flank wear criterion for the cutting tool to integrate tool life and the surface roughness requirements of the finish milling process. An annealed Ti-6Al-4V alloy was selected as the workpiece material, undergoing end milling with uncoated carbide inserts. The flank wear of the insert was observed and measured with the toolmaker's microscope. To examine machined surfaces, 3D surface topography was provided by the white light interferometer, and the arithmetical mean roughness (Ra) was calculated with the WYKO Vision32 software. The flank wear increases with cutting time, and the maximal flank wear is set as the flank wear criterion. As the cutting process progresses, tool wear is the predominant factor affecting the variation of surface roughness. According to the plots for the tool wear propagation and surface roughness variation, an optimal flank wear criterion can be defined which integrates the tool life and the surface roughness requirements for the finish milling process.

关键词： Tool wear Surface topography Surface roughness Optimal flank wear criterion

Phase Transformation and Carbide Precipitation of Functional Gradient Semi-solid 9Cr18 Steel

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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 823-830页

作者： Yong-Jin Wang Ren-Bo song Ren-feng song School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Institute of Industrial Science The University of TokyoKomaba 4-6-1MeguroTokyo 153-8505Japan Ansteel Mining Engineering Corporation Anshan 114004China

The unique phase transformation and carbide evolution in 9Cr18 steel were investigated during semi-solid forming and subsequent heat treatment. The functional gradient thixoforging 9Cr18 component was divided into inner area and edge area. Microstructure evolution was different at each area. After semi-solid cooling, the solid particles in the inner area were retained as meta-austenite. During annealing, M_（23）C_6 carbide began to precipitate when temperature reached 700 °*** transformation occurred when temperature reached 800 °C. The occurrence of M_（23）C_6 carbide and martensite structure would be harmful to the mechanical properties of inner area. In the edge area, the liquid underwent eutectic transformation to form bar-shape M_7C_3 carbide and secondary austenite after semi-solid cooling. The width of bar-shape carbide would decrease during annealing. By controlling the carbide evolution, we could tailor the functional gradient material with required property.

关键词： Semi-solid forming Solid/liquid phase Annealing Carbide precipitation

Dominance property based tabu search for single machine scheduling problems with family setups

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1233-1238页

作者： Jin feng song Shiji Wu Cheng Dept. of Automation Tsinghua Univ. Beijing 100084 P. R. China

The problem of minimizing the maximum lateness on a single machine with family setups is *** solve the problem, dominance property is studied and then introduced into the tabu search（TS） *** the dominance property, most unpromising neighbors can be excluded from the neighborhood, which makes the search process always focus on the most promising areas of the solution *** proposed algorithms are tested both on the randomly generated problems and on the real-life *** results show that the proposed TS algorithm outperforms the best existing algorithm and can solve the real-life problems in about 1.3 on average.

关键词： single machine family setups tabu search dominance property.

Numerical Study on Pressure Drop Factor in the Vent-Cap of CDQ Shaft

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Journal of Thermal Science 2008年第1期17卷 69-76页

作者： Bo song Yanhui feng Xinxin Zhang Department of Thermal Engineering School of Mechanical EngineeringUniversity of Science and Technology Beijing Beijing 100083 China

In CDQ （Coke Dry Quenching） shaft, the vent-cap with complex structure is installed in the cone-shaped funnel under the cooling chamber. It acts to introduce cooling gas and support the descending coke in the chamber. The designing and installation of vent-cap aim to get relatively uniform gas distribution, to reduce the temperature fluctuation of cokes at outlet and realize stable operation of CDQ apparatus. In this paper, the turbulent flow of gas in vent-cap of 1：7 scale CDQ experimental shaft is numerically simulated by using CFD （Computational Fluid Dynamics） software, CFX. The velocity field, the outlet flux distribution and the pressure drop factor of each outlet under three kinds of vent-cap （called high vent-cap, low vent-cap and elliptic vent-cap） are analysed and compared. The results turn out that the pressure drop factor of elliptic vent-cap is larger than the other two vent-caps, and that the pressure drop factors of high vent-cap and low vent-cap almost have the same value. While for a specified vent-cap, the pressure drop factor with pressing brick is larger than that without pressing brick. The work in this paper is valuable for the designing of vent-cap for large-scale CDQ shaft.

关键词： CDQ Vent-cap Pressure drop Numerical simulation

Theoretical calculation and experimental study on the interaction mechanism between TKX-50 and AP

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Defence Technology（防务技术） 2020年第4期16卷 825-833页

作者： Jun Tao Xiao-feng Wang Kun Zhang Xue-song feng The Second Department Xi'an Modern Chemistry Research InstituteXi'an 710065China

The combination of 5,5'-bistetrazole-1,1'-diolate(TKX-50) and ammonium perchlorate(AP) can make greater use of the chemical energy of TKX-50 based energetic *** research on the interaction mechanism between TKX-50 and AP is very important for designing TKX-50-AP compounds and judging the formation feasibility of composite particles,which can lay a theoretical foundation for the preparation of TKX-50-AP mixed crystals and the application of TKX-50 in propellant,propellant and ***,in order to research the interaction mechanism between TKX-50 and AP,density-functional theory calculation was applied to optimize three configurations of TKX-50-AP *** geometry structure,electrostatic potential and binding energy of the compounds were predicted,and the electronic density topological analysis was also carried *** TKX-50-AP mixed crystals structures were constructed,and the radial distribution function of H-O and H-N in mixed crystals was ***,solvent/non-solvent method was applied to prepare TKX-50-AP composites,and the infrared spectro scopy and the non-isothermal decomposition perfo rmance of the composites were *** show that the superposition of positive charges in TKX-50 molecule and negative charges in AP makes the electrostatic potential distributions of TKX-50-AP compounds different from that of TKX-50 and *** interaction energies of TKX-50-AP 1,TKX-50-AP 2 and TKX-50-AP 3 are 39.743 kJ/mol,61.206 kJ/mol and 27.702 kJ/mol,*** interaction between TKX-50 molecules and AP molecules in TKX-50-AP mixed crystals both depends on hydrogen bonds and van der Waals force,and the number and strength of hydrogen bonds are significantly greater than that of van der Waals *** composition of AP and TKX-50 makes the absorption peak of the five-membered rings and NH_3 OH^+ of TKX-50 shift to low wavenumber in the infrared *** general,TKX-50 interacts with AP via hydrogen bonds and va

关键词： 5,5'-bistetrazole-1,1'-diolate Ammonium perchlorate Density-functional theory Molecular dynamics Hydrogen bond

Variability of Pesticide Residues in Vegetables from the Marketplaces in Jinan City

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Agricultural Sciences in China 2011年第10期10卷 1646-1652页

作者： song Yu-feng LU Xiao REN feng-shan Central Laboratory of Shandong Academy of Agricultural Sciences/Key Laboratory of Test Technology on Food Quality and Safety of Shandong Province Jinan 250100 P.R.China Institute of Agricultural Quality Standards and Testing Technology Shandong Academy of Agricultural Sciences Jinan 250100 P.R. China

In order to provide technological support for risk estimation of pesticide residues taken from vegetables, the residues of pesticide in vegetables in Jinan City, China, were investigated. Moreover, the variability of pesticide residues in vegetables was explored, and the variability factor was calculated. The level of pesticide residue was studied by statistical method. The variability factor was calculated using the Harrell-Davis method in accordance with principles recommended by the JMPR. In addition, the procedure of evaluation was validated according to the principles laid down by the JMPR （Joint Meeting on Pesticide Residues）. The detection rate of pesticide residues in all marketplace samples was less than 20% in Jinan City. The unqualified rate of vegetables was low （0.6%）. The chlorothalonil was found as the pesticide with the highest rate of detection. The vegetables with the highest rate of pesticide residues detected were leafy vegetables. The relationship between variability factor and mean value of concentrations of contaminations was expressed by the formula, v=4.9×Cmean. The pesticide residues in vegetables from Jinan City is low. The evaluated variability factor is larger than that the value recommended by the JMPR, however, less than the default value used for acute intake assessment of pesticide residues in UK in most cases.

关键词： variability variability factor risk assessment pesticide residues

A distributed non-point source pollution model: calibration and validation in the Yellow River Basin

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Journal of Environmental Sciences 2004年第4期16卷 646-650页

作者： HAOFang-hua ZHANGXue-song YANGZhi-feng InstituteofEnvironmentalSciences BeijingNormalUniversityBeijing100875China

The applicability of a non-point source pollution model—SWAT(soil and water assessment tools) in a large river basin with high sediment runoff modulus(770 t/km2 in the Yellow River) was examined. The basic database, which includes DEM, soil and landuse map, weather data, and land management data, was established for the study area using GIS. A two-stage “Brute Force' optimization method was used to calibrate the parameters with the observed monthly flow and sediment data from 1992 to 1997. In the process of calibration automated digital filter technique was used to separate direct runoff and base flow. The direct runoff was firstly calibrated, and the base flow, then the total runoff was matched. The sediment yield was calibrated to match well. Keeping input parameters set during the calibration process unchanged, the model was validated with 1998—1999's observed monthly flow and sediment. The evaluation coefficients for simulated and observed flow and sediment showed that SWAT was successfully applied in the study area: relative error was within 20%, coefficient of determination and Nash-Suttcliffe simulation efficiency were all equal to or above 0.70 during calibration and validation period.

关键词： Yellow River SWAT sediment flow non-point source pollution