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Calculation of maximum ground movement and deformation caused by mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 562-569页

作者： LI Pei-xian1, 2. TAN Zhi-xiang1, 2. DENG Ka-zhong1, 2.1. Key laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping, china University of Mining and {2., Xuzhou 2.1116, china 2. Jiangsu Key laboratory of Resources and Environmental Information Engineering, china University of Mining and {2., Xuzhou 2.1116, china [a] Key laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China [b] Jiangsu Key laboratory of Resources and Environmental Information Engineering China University of Mining and Technology Xuzhou 221116 China

In order to know the maximum mining ground deformation of arbitrary surface point, directions of the maximum surface tilt, curvature,horizontal displacement and horizontal deformation caused by multi-working faces were deduced based on probability integral method. The distribution forms of surface deformations in all direction φ∈[0, 2.] were obtained and also equations of maximum deformations were given based on calculation of mining ground deformation in direction φ. A mining subsidence analysis system was developed with VB6.0. The system implements the probability integral mining subsidence prediction with direct integration method, and it can avoid errors of arbitrary shaped working face subdivision of traditional method, and accuracy of mining subsidence prediction can be improved with the direct integral method. The system implements the contour chart and profile chart and also data analysis automation by manipulation of the SURFER kernel function and it complements the defect of existing subsidence prediction software. Calculation of maximum deformations caused by multi-working faces mining in a coal mine of Xuzhou, china was shown as application example. Engineering application indicates that maximum deformation of mining ground surface can be calculated and analyzed by the system. The research provides a theoretical basis and calculation tool for mining subsidence prediction and analysis.

关键词： mining subsidence probability integral method movement and deformation system development

REACTION MECHANISM OF BENZOPHENONE-PHOTOINITIATED CROSSLINKING OF POLYETHYLENE

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Chinese Journal of Polymer science 2002年第4期20卷 291-307页

作者： Bao-jun Qu State Key laboratory of Fire science and Department of Polymer science and Engineering University of science and technology of china hefei 2.002. china Univ Sci & Technol china State Key Lab Fire Sci Hefei 230026 Peoples R China Univ Sci & Technol china Dept Polymer Sci & Engn Hefei 230026 Peoples R China

The radical intermediates, the crosslink microstructures, and the reaction mechanism of benzophenone (BP)-photoinitiated crosslinking of low-density polyethylene (LDPE) and model compounds (MD) have been reviewed in detail. The spin-trapping electron spin resonance (ESR) spectra obtained from the LDPE/BP systems with spin-trap agents show that two kinds of polymer radical intermediates are mainly formed: tertiary carbon and secondary carbon radicals. The spin-trapping ESR studies of MD/BP systems give further evidence that photocrosslinking reactions of PE predominantly take place a sites of tertiary carbon, secondary carbon, and especially allylic carbon when available. The high resolution C-13-NMR spectra obtained from LDPE and MD systems show that the crosslink microstructures have H- and Y-type links and that their concentrations are of the same order. The fluorescence, ESR, C-13 and H-1-NMR spectra from the PE and MD systems demonstrate that the main photoreduction product of BP (PPB) is benzpinacol formed by the recombination of two diphenylhydroxymethyl (K-.) radical intermediates. Two new PPB products: an isomer of benzpinacol with quinoid structure, 1-phenylhydroxymethylene-4-diphenylhydroxymethyl-2.5-cyclobexadiene and three kinds of alpha-alkyl-benzhydrols have been detected and identified. These results provide new experimental evidence for elucidating the reaction mechanism in the BP-photoinitiated crosslinking of polyethylene.

关键词： photocrosslinking mechanism polymer radical intermediates crosslink microstructures photolytic products of benzophenone polyethylene model compound

An experimental study on the self-adaption mechanism used by evolutionary programming

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Progress in Natural science:Materials International 2008年第4期18卷 481-486页

作者： Jingsong He a,b, a Department of Electronic science and technology, University of science and technology of china, hefei 2.002., china b Nature Inspired Computation and Application laboratory, University of science and technology of china, hefei 2.002., china Department of Electronic science and technology University of Science and Technology of China Hefei 230027 China Nature Inspired Computation and Application laboratory University of Science and Technology of China Hefei 230027 China

Evolutionary programming (EP) is one of the most important methods for numerical optimization. Its main technique is the combi- nation of mutations and the self-adaption mechanism. In the past years, studies on EP focused on how to improve the effciency of muta- tions with different probability distributions, and few of them touched on the question that the self-adaption mechanism did not work sometimes, but simply followed the original suggestion. So far, no experimental results have shown why this is a question. This paper firstly gives a primary analysis on the behavior of the self-adaption mechanism, and then presents experimental evidences to show why its adaptive ability is doubtful.

关键词： Evolutionary programming Cauchy mutation Self-adaption mechanism

Charge order and spin order in Nd_(0.5)Sr_(0.5)Mn_(1-x)(Ga_x, Ti_x)O_3 system

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science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 294-302页

作者： REN QingBao1,2. ZHU WeiTing1, HONG Bo2.& ZHANG YuHeng2.1 Department of Physics, Lishui University, Lishui 32.000, china 2.National High Magnetic Field laboratory, University of {2. and technology of china, hefei 2.002., china 1. Department of Physics Lishui University Lishui 323000 China 2. National High Magnetic Field laboratory University of Science and Technology of China Hefei 230026 China

Magnetic properties of Nd_(0.5)Sr_(0.5)Mn_(1-x)(Ga_x, Ti_x)O_3 system (0.04≤x≤0.4) were inves- tigated through magnetization and electron spin resonance (ESR) measurements. It was observed that a small amount of Ti substitution for Mn will destroy the charge-ordering (CO) phase completely and induce the cluster-spin-glass phase in the system, which displays a procedure of collapse of CO and of an enhancement of spin ordering (SO) phase. In contrast, the Ga substitution for Mn induces a melt- ing of CO phase in the system. It was observed that with substitution the CO phase is suppressed gradually and the remanent CO phase is retained all the while, and withal, there is a co-existence of AFM CO phase and FM SO at low temperature. In addition, an abrupt rise of magnetization was observed in M-T curves. We attributed this abnormal phenomenon to a transition from canted AFM SO to FM SO in CO region.

关键词： charge ordering spin ordering antiferromagnetic transition

Transport Property of La0.67-xSmxSr0.33MnO3 at Heavy Samarium Doping （0.40≤x≤0.60）

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Journal of Rare Earths 2006年第2期 206-213页

作者： Guo Huanyin 1, Liu Ning 1,2., Yan Guoqing 1, Tong Wei2.1. Materials research laboratory, Suzhou College, Suzhou 2.4000, {2. 2. structure research laboratory, University and technology of {2., hefei 2.002., {2.) Materials research laboratory Suzhou College Suzhou 234000 China structure research {2. University and Technology of China Hefei 230026 China

The influence of heavy samarion （Sm） doping（0.40≤x≤0.60） on magnetic and electric properties of La0.67-xSmxSr0.33MnO3was investigated by measuring the magnetization-temperature （M～T） curves, magnetization-magnetic density （M～H） curves, resistivity-temperature（ρ-T） curves and magnetoresistivity-temperature（MR～T） curves of the samples under different temperatures. It is found that, with the increase of Sm doping amount, the samples transform from long-range ferromagnetic order to spin-cluster glass state and anti-ferromagnetic state; and when x=0.60, the transport property becomes abnormal under magnetic background; and the magnetic structure changes and extra magnetic coupling induced by doping leads to colossal magnetoresistance effect. The transport mechanism of metallic conduction at low temperature is mainly electron-magneton interaction and can be fitted by the formula ρ=ρ0+AT 4.5 , and the insulator-like transport mechanism on high temperature range is mainly the function of variable-range hopping and can be fitted by the formula ρ=ρ0exp（T0/T） 1/4 . In the formulas above, ρ is resistivity, T is temperature, and A, ρ0, T0are constants.

关键词： giant magnetoresistant material magnetic structure transport behavior electron-magneton interaction variable-range hopping samarion doping rare earths

Orientational phase transition in C_(60) single crystal under high pressure

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Chinese science Bulletin 1998年第16期43卷 1341-1344页

作者： XIE Bin+1, WANG Haiqian+1, WANG Qiang+1, HOU Jianguo+1, XU Bo+2. TAN Mingqiu+2. LI Hongnian+2.and XU Yabo+2.1. structure research {2. and Center for Fundamental Physics, University of science and technology of china, hefei 2.002., china 2. Depart structure research {2. and Center for Fundamental Physics University of Science and Technology of China Hefei China Department of Physics Zhejiang University Hangzhou China

By using a piston-cylinder type hydrostatic high-pressure unit, the electrical dc conductance of bulk C 60 single crystal was measured in the pressure range of 0 to 0.6 GPa at 2.0 K. With increasing pressure, a discontinuous increase of the conductance was observed at the pressure of 0.176 GPa, which can be ascribed to the orientational ordering phase transition. In the simple cubic phase, the increase of conductance with increasing pressure is faster than that in the face-centered-cubic phase.

关键词： C 60 high pressure conductivity.

A new method for mining deformation monitoring with GPS-RTK

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中国有色金属学会会刊：英文版 2011年第S3期21卷 659-664页

作者： GAO Jing-xiang1, 2. LIU Chao2. WANG Jian1, 2. LI Zeng-ke2. MENG Xiang-chao2.1. Key laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping, china University of Mining and {2., Xuzhou 2.1116, china 2. School of Environment and Spatial Informatics, china University of Mining and {2., Xuzhou 2.1116, china [a] Key laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China [b] School of Environment and Spatial Informatics China University of Mining and Technology Xuzhou 221116 China

Based on ranging intersection theory, a new method which is simple and easy to operate was proposed for data collection in the mine surface deformation monitoring with GPS-RTK centering rod measurements. It can fully eliminate the inevitable shaking error and the vertical deflection, and to some extent weaken the multipath effect on the estimates of coordinates in a relatively short period of time, using high-frequency observations. The results show that three-dimensional coordinates with a height accuracy better than 1 cm, horizontal accuracy better than 2.4 cm can be achieved through only 15-30 s continuous observation by 2. Hz high-frequency and effectively improve the measurement accuracy and efficiency of RTK, fully satisfying the high-speed and high-precision data acquisition in mine surface subsidence deformation monitoring.

关键词： GPS rover pole multipath delay deformation monitoring

Bell violation for the thermal states of an XXZ spin chain with Dzialoshiski-Moriya interaction

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science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2074-2079页

作者： MA XiaoSan 1 & WANG AnMin 2.1 School of Electric Engineering and Information,Anhui University of technology,Maanshan 2.3002.china 2.Department of Modern Physics,University of {2. and technology of china,hefei 2.002.,china 1. School of Electric Engineering and Information Anhui University of Technology Maanshan 243002 China2. Department of Modern Physics University of Science and Technology of China Hefei 230026 China

The effect of Dzialoshiski-Moriya (DM) interaction on the violation of Bell inequality for thermal states of interacting qubits via a two-qubit XXZ spin chain is *** results imply that the DM interaction and anisotropy taking a large positive value can enhance the Bell violation and improve the threshold temperatures of *** the comparison between the Bell violation and thermal entanglement,we find that the threshold temperatures of thermal entanglement are higher than those of the Bell *** implies that some states are entangled but the Bell inequality is not violated.

关键词： Bell violation threshold temperatures DM interaction

EFFECT OF BIAS STRESS ON NON-LINEAR INTERNAL FRICTION OF Al-Mg ALLOY

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Acta Metallurgica Sinica(English Letters) 1992年第3期5卷 166-171页

作者： TAN Qi University of science and technology of {2.,hefei,{2. Univ of science and technology of China Hefei China

The influence of longitudinal and torsional bias stresses on anomalous amplitude-dependent internal friction was *** longitudinal bias stress may always weaken the anomalous amplitude-dependent effect,while the torsional one may induce different effects from differ- ent directions *** stress effect exhibits only in properly heat treated and cold worked ahoy *** anomalous amplitude-dependent internal friction peaks,P_3,P_2.and P_1, are found to be related closely to slant dislocation kink ***,the application of bias stress to internal friction would be contributed to the study on dislocation structure.

关键词： internal friction bias stress anomalous amplitude effect dislocation kink