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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 {2. of Mining and technology, Xuzhou 2.1116, china 2. Jiangsu Key Laboratory of Resources and environmental Information Engineering, china {2. of Mining and technology, 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

Characterzation and separation of Al_(13) species using gel-filtration chromatography

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science china Chemistry 2006年第4期49卷 326-331页

作者： CHU Yongbao1,2. GAO Baoyu1, YUE Qinyan1, WANG Yan1 & WANG Shuguang1 1. School of environmental science and Engineering, Shandong {2., Jinan 2.0100, china 2. college of material and environment, Qingdao {2. of science and technology, Qingdao 2.6042. china School of environmental science and Engineering Shandong University Jinan China college of material and {2. Qingdao University of Science and Technology Qingdao China

A polyaluminum chloride (PAC) sample was prepared using a slow alkalinetitration method. The Bio-Gel P-100 gel column chromatographic technique was used to separate andcharacterize the various forms of aluminum present in the prepared PAC solution. The effluents froma gel column were monitored using online chemical method: AI-Ferron timed complexationspectropho-tometry and by ^(2.)Al nuclear magnetic resonance (NMR) spectroscopy. Effects ofdifferent experimental conditions such as eluent flow rate, ionic strength and pH on separation ofAl_(13) were investigated. Experimental results indicated that molecule size exclusion was not theonly parameter affecting the column chromatographic separation efficiency of Al_(13) but moleculecharge as well. Reducing the eluent flow rate, increasing the ionic strength and suitable pHresulted in increase in the separation efficiency. Experimental results clearly indicated that byvarying the experimental conditions, it is possible to produce pure Al_(13) species using a gelcolumn chromatographic technique.

关键词： Al13 species, column chromatography, polyaluminum chloride (PAC), separation and purification.

Synthetically adaptive robust filtering for satellite orbit determination

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science china Earth sciences 2004年第7期47卷 585-592页

作者： YANG Yuanxi1 & WEN Yuanlan2.1. Xi’an Research Institute of Surveying and Mapping, Xi抋’an 710054, china 2. college of Aerospace and {2. Engineering, National university of Defense technology, Changsha 410073, china 1. Xi’an Research Institute of Surveying and Mapping 710054 Xi’an China 2. college of Aerospace and material Engineering National University of Defense Technology 410073 Changsha China

The quality of the satellite orbit determination is rested on the knowledge of per-turbing forces acting on the satellite and stochastic properties of the observations, and the ability of controlling various kinds of errors. After a brief discussion on the dynamic and geometric orbit determinations, Sage adaptive filtering and robust filtering are reviewed. A new synthetically adaptive robust filtering based on a combination of robust filtering and Sage filtering is *** is shown, by derivations and calculations, that the synthetically adaptive robust filtering for orbit determination is not only robust but also simple in calculation. It controls the effects of the outliers of tracking observations and the satellite dynamical disturbance on the parameter esti-mates of the satellite orbit.

关键词： satellite orbit, Sage filtering, adaptive orbit determination, robust estimation.

Terrain classification based on adaptive weights with airborne LiDAR data for mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 648-653页

作者： LI Hui-ying1, WANG Zhi2. SUN Ya-feng1, LI Wen-hui1 1. college of Computer science and {2., Jilin university, Changchun 130012. china 2. college of Resources and Civil Engineering, Northeastern university, Shenyang 110004, china [a] college of Computer science and {2. Jilin University Changchun 130012 China [b] college of Resources and Civil Engineering Northeastern University Shenyang 110004 China

The fast high-efficiency inspection for mining subsidence of mine area is a reliable way for forecasting accident and evaluating losing expense. In order to monitor mining subsidence of exploitation mine efficiently, LiDAR data were used and a novel strip division method was brought forward based on separating-treatment theory, which divided the mass of discrete three-dimensional point cloud data into a series of parallel strips and reduced the dimension in each strip. Polynomial fitting algorithm based on the adaptive weights, which located in the range of the strip, was used for classification complex terrain data of mine-area. The results show that LiDAR datamation can be greatly reduced. In the mean time, the time spending for calculation is shortened, and computational complexity is simplified. Therefore, high-efficiency terrain classification of LiDAR point cloud method can be great beneficial to monitoring environment of mine area.

关键词： mining subsidence airborne LiDAR strip division adaptive weights

Effect of Ultrafine Grinding on Dissolving-out Quantity of Tanshinone IIA from Radix Salvia Miltiorrhiza

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Journal of Wuhan university of technology({2.s science) 2009年第6期24卷 973-976页

作者：苏艳丽傅正 college of Chemistry Chemical Engineering and Material ScienceSoochow UniversitySuzhou China State Key Laboratory of Advanced technology for material Synthesis and Processing Wuhan University of Technology

In order to improve the bioavailability, Radix salvia miltiorrhiza raw powder mixed with distilled water （5.5wt%） was ultrafinely ground to nanosize particles using HSCS pulverizer, and the dissolving-out quantity of tanshinone IIA in the filtrate that obtained from nanoparticles suspension and raw powder marinated in water for different time was determined by HPLC. The experimental results show that raw powder can be ultrafinely ground to 133.5 nm at 1500 r/min for 50 min and the molecular structure of active ingredients doesnot change, and the dissolving-out quantity of tanshinone IIA obtained from the filtrate is increased greatly from 12.77 μg/g to 54.55 μg/g.

关键词： Radix salvia miltiorrhiza tanshinoe IIA HPLC dissolving-out quantity

Synthesis and Luminescence Properties of Red Phosphor CaO:Eu^(3+)

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Journal of Wuhan university of technology({2.s science) 2009年第1期24卷 20-24页

作者：康明 School of material science and Engineering Southwest University of Science and Technology college of materials {2. and Engineering Sichuan University

Ca（NO3）2.4H2., Eu（NO3）3 and H2.2.4·2.2. were adopted to synthesize CaO： Eu3＋ with the chemical co-precipitation method, and the effects of the calcination temperature and Eu3＋ doping concentration on the phosphor structure and its luminescent properties were investigated by TG-SDTA, XRD, and PL-PLE. The results confirm that the Eu3＋ ions as luminescent centers substi-tutes Ca2. sites without changing the crystal structure of cubic CaO. The optimum calcination tem-perature and the optimum concentration of Eu3＋ are 1 100 ℃ and 1 mol%, respectively, under which the best crystallinity and highest PL intensity appeared. The maximum emission wavelength is 592.nm （5D0→7F1） which is excited by xenon lamp with the wavelength of 2.0-2.0 nm, indicating that the Eu3＋ ion mainly locates in the symmetric position （Oh） in the crystal lattice of CaO.

关键词： red phosphor CaO Eu^3+ co-precipitation method rare earths

Energy-Based Prediction of Low Cycle Fatigue Life of High-Strength Structural Steel

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Journal of Iron and Steel Research International 2012年第10期19卷 47-53页

作者： LUO Yun-rong1,2. HUANG Chong-xiang1, GUO Yi2. WANG Qing-yuan1 (1. college of Architecture and environment, Sichuan {2., Chengdu 610065, Sichuan, china 2. college of Mechanical Engineering, Sichuan {2. of science and Engineering, Zigong 643000, Sichuan, china) [a] college of Architecture and environment. Sichuan {2. Chengdu 610065 Sichuan China [b] college of Mechanical Engineering. Sichuan university of {2. and Engineering Zigong 643000 Sichuan China

Energy-based models for predicting the low-cycle fatigue life of high-strength structural steels are presented. The models are based on energy dissipation during average of cycles, cycles to crack propagation and total cycles to failure. Plastic strain energy per cycle was determined and found as an important characteristic for initiation and propagation of fatigue cracks for high-strength structural steels. Fatigue strain-life curves were generated using plastic energy dissipation per cycle (loop area) and compared with the Coffin-Manson relation. Low cycle fatigue life was found similar from both methods. The material showed Masing-type behavior. The cyclic hysterisis energy per cycle was calculated from cyclic stress-strain parameters. The fracture surfaces of the fatigue samples were characterized by scanning electron microscope and the fracture mechanisms were discussed.

关键词： low cycle fatigue high-strength steel energy-based model fatigue life

Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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science china Chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2. HONG Xiaozhong3, GU Fang1 & BA Xinwu1 1. college of Chemistry and environment {2., Hebei university, Baoding 071002. china 2. International Center for materials Physics, Chinese Academy of {2.s, Shenyang 110016, china 3. college of Physics {2. and technology, Hebei university, Baoding 071002. china 1. college of Chemistry and environment {2. Hebei University Baoding 071002 China 2. International Center for materials Physics Chinese Academy of Sciences Shenyang 110016 China 3. college of Physics science and {2. Hebei University Baoding 071002 China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science china(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2. LIU GuoQuan2. LI ZhiLin3, FENG ChengMing1 1 Mechanical and Electronic Engineering college, Shandong Agricultural university, Tai’an 2.1018, {2. 2.college of materials science and Engineering, university of science and technology, Beijing 100083, {2. 3 college of material science and Engineering, Beijing university of Chemical technology, Beijing 10002., {2. Mechanical Electronic Engineering college Shandong Agricultural University Tai’an 271018 China college of materials {2. Engineering University of Science technology Beijing 100083 China college of material {2. Engineering Beijing University of Chemical Technology Beijing 100029 China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements