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Chromium leaching mechanism of coal mine water—a modeling study based on Xuzhou-Datun coal mine district

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mining science and {2. 2010年第1期20卷 97-102页

作者： SHAN Yao QIN Yong, WANG Wenfeng school of Resource and Earth science, {2. university of mining & technology, Xuzhou 2.1116, {2. [a] school of Resource Earth science China University of Mining & Technology Xuzhou 221116 China

In order to investigate chromium contamination of coal mine water, to analyze chromium leaching mechanism and to evaluate environment pollution potential of coal mine water, we perform site investigations, physical and computer modeling in the Xuzhou-Datun coal mine district. The result of our test samples shows that chromium concentration was 9 μg/L in roof leachate and 3 μg/L in coal leachate. The host rock has a higher pollution potential than that of coal seams. Leaching experiments and XRD test results indicate that chromium is released from the process of transforming illite to kaolinite. The pH, pe and temperature of coal mine water affect the chromium leaching behavior. Modeling results suggest that the adsorption of adsorbents controls chromium concentration in coal mine water. The chromium adsorption ratio is quite low in both an acid and in an alkaline environment. Therefore, coal mine water has a high pollution potential. Under other conditions, chromium adsorption is stronger in a neutral water environment, so that chromium concentrations may be very low.

关键词： chromium coal mine water leaching

Practice and technical approach of GPS observation of mining-induced ground subsidence

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中国有色金属学会会刊：英文版 2005年第S1期15卷 65-68页

作者： GAO Jun-hai~(1,2. WU Li-xin~1 (1. china university of mining and technology Beijing Campus, Beijing 100083. {2. 2. Tangshan Branch, {2. Coal Research Institute, Tangshan 063012. {2.) china Univ Min & Technol Beijing 100083 Peoples R China china Coal Res Inst Tangshan Branch Tangshan 063012 Peoples R China

The base vector between 2.poins and a high-precision geodetic height difference can be obtained by GPS. If the geodetic height of a point is known, the geodetic height of each observation point in a net can be obtained. When surveying the subsidence value in the mining-induced ground subsidence, the change of the height of monitoring point is needed. On the above theoretical basis, the problem involved in GPS observation of mining-induced ground subsidence and their counter measures were discussed, and an introduction was made that the subsidence value obtained in the monitoring mining-induced ground subsidence can use the change of height of geodetic as a alternative, the result of check on the accuracy and reliability of repetitions observations was analysed. Finally, the effect of errors on accuracy of GPS observation and their reduction measures were elaborated.

关键词： mining-induced ground subsidence GPS observation observation accuracy reliability

Experimental study of dynamic mechanical properties of reactive powder concrete under high-strain-rate impacts

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science china(Technological sciences) 2010年第9期53卷 2435-2449页

作者： JU Yang1,2.LIU HongBin1,SHENG GuoHua1,3 & WANG HuiJie1 1 State Key Laboratory of Coal Resources and Safe mining,Beijing Key Laboratory of Fracture and Damage Mechanics of Rocks and Concrete,china {2. of mining and technology,Beijing 100083.china 2.Department of Mechanical and Manufacturing engineering,{2. of Calgary,2.00 {2. Drive,AB T2. 1N4,Canada 3 school of Resources and Civil engineering,Northeastern {2.,Shenyang 110004,china 1. State Key Laboratory of Coal Resources and Safe mining Beijing Key Laboratory of Fracture and Damage Mechanics of Rocks and Concrete China University of Mining and Technology Beijing 100083 China2. Department of Mechanical and Manufacturing Engineering University of Calgary 2500 University Drive AB T2N 1N4 Calgary Canada3. School of Resources and Civil Engineering Northeastern University Shenyang 110004 China

The dynamic mechanical properties of reactive powder concrete subjected to compressive impacts with high strain rates ranging from 10 to 1.1×102.s-1 were investigated by means of SHPB (split-Hopkinson-pressure-bar) tests of the cylindrical specimens with five different steel fiber volumetric *** properties of wave stress transmission,failure,strength,and energy consumption of RPC with varied fiber volumes and impact strain rates were *** influences of impact strain rates and fiber volumes on those properties were characterized as *** general forms of the dynamic stress-strain relationships of RPC were modeled based on the experimental *** investigations indicate that for the plain RPC the stress response is greater than the strain response,showing strong brittle *** RPC with a certain volume of fibers sustains higher strain rate impact and exhibits better deformability as compared with the plain *** a constant fiber fraction,the peak compressive strength,corresponding peak strain and the residual strain of the fiber-reinforced RPC rise by varying amounts when the impact strain rate increases,with the residual strain demonstrating the greatest *** the fiber content makes trivial contribution to improving the residual deformability of RPC when the impact strain rate is *** tests also show that the fiber content affects the peak compressive strength and the peak deformability of RPC in a different *** a constant impact strain rate and the fiber fraction less than 1.75%,the peak compressive strength rises with an increasing fiber *** peak compressive strength tends to decrease as the fiber volume exceeds 1.75%.The corresponding peak strain,however,incessantly rises with the increasing fiber *** total energy Edisp that RPC consumed during the period from the beginning of impacts to the time of residual strains elevates with the fiber volume increment as long as the fiber fraction

关键词： impact reactive powder concrete (RPC) high strain rate dynamic strength energy consumption dynamic stress-strain response

Degradation of lignite model compounds by the action of white rot fungi

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mining science and {2. 2010年第1期20卷 76-81页

作者： DU Ying, TAO Xiuxiang, SHI Kaiyi, LI Yang school of Chemical engineering and {2., china university of mining & {2., Xuzhou 2.1000, china [a] school of Chemical engineering technology China University of Mining & Technology Xuzhou 221000 China

Three compounds modeled on the lignite structure were chosen for experimental degradation by different fungi strains. Culture conditions and extracellular enzyme activities were optimized. The growth curves of the strains were determined to study mycelium dry weight and protein content changes. Gas chromatography and infrared spectroscopy were used to detect changes of functional groups before and after the action of the fungi on the model compounds. Possible decomposition products and degrada-tion mechanisms were proposed. The research findings show that C. Versicolor and Golden Mushroom can grow in presence of the model compounds. The optimum culture conditions were a pH of 6.0, a carbon-nitrogen ratio of five and a Tween-80 concentration of 0.1%. Newly produced substances were found by gas chromatography. Infrared analysis showed that the model compounds degraded under the action of the microorganisms.

关键词： coal biotransformation white rot fungi mechanism model compound

Boundedness for commutators of fractional Hardy operators on Herz spaces

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Progress in Natural science:Materials International 2007年第1期17卷 20-25页

作者： FU Zunwei, LIU Zongguang and LU Shanzhen ( school of Mathematical sciences, Beijing Normal {2., Beijing 100875, china Department of Mathematics, Linyi Normal {2., Linyi 2.6005, china Department of Mathematics, china university of mining and technology, Beijing 100083. china) [a]school of Mathematical sciences Beijing Normal University Beijing China [b]Departhent of Mathematics Linyi Normal University Linyi China [c]Departhent of Mathematics China University of Mining and Technology Beijing China

Some boundedness results are established for commutators generated by classical fractional Hardy operators and one-sided CMO functions on the homogeneous Herz spaces, which extends some known results.

关键词： fractional Hardy operator Hardy’s integral inequality commutator one-sided CMO function homogeneous Herz space.

Characteristics of Water Absorption and the Loss of Dust-Sticking Agent

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 1-3页

作者： Longzhe Jin Thongan Jiang Auiying Jin (Resources engineering school, {2. of science and technology Beijing, Beijing 10083, china) Resources engineering school University of Science and Technology Beijing Beijing 10083 China

The development of NCZ-1 dust-sticking agent was first intreduced in china. The speed of water absorption of dust-stick-ing agent was measured and studied on mining site and in laboratory, and then the law of water absorption of dust-sticking agent was analyzed. In addition, the mathematical model of the loss rate of dust-sticking agent was established by the application of fluid mechanics theory, and the method of determining the sprinkle parameters of dust-sticking agent was obtained. Through practical verifi-cation, it is found that the error of this mathematical model is less than 10%. So it can be used in the field.

关键词： dust-sticking, water absorption loss rate mathematical model

A new approach toward object-based change detection

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science china(Technological sciences) 2010年第S1期53卷 105-110页

作者： ZHANG Guo1,2.LI Yang1 & LI ZhiJiang3 1 State Key Laboratory of Information engineering in surveying,Mapping and Remote Sensing,Wuhan {2.,Wuhan 430079,china 2.Satellite of surveying and Mapping Application center,State Bureau of surveying and Mapping,Beijing 100830,china 3 school of Printing and Packaging,Wuhan {2.,Wuhan 430079,china Wuhan Univ State Key Lab Informat Engn Surveying Mapping & R Wuhan 430079 Peoples R China State Bur surveying & Mapping Satellite Surveying & Mapping Applicat Ctr Beijing 100830 Peoples R China Wuhan Univ Sch Printing & Packaging Wuhan 430079 Peoples R China

Object-based change detection has been the hotspot in remote sensing image processing.A new approach toward object-based change detection is *** two different temporal images are unitedly segmented using the mean shift procedure to obtain corresponding *** change detection is implemented based on the integration of corresponding objects’ intensity and texture *** are conducted on both panchromatic images and multispectral images and the results show that the integrated measure is robust with respect to illumination changes and *** color detection is conducted to determine whether the color of the unchanged objects changes or not when dealing with multispectral *** verification work is carried out to show the accuracy of the proposed approach.

关键词： mean shift united segmentation change detection object-based intensity texture integration

Improving anti-sulfur performance of methane sensors by new vectors and active components

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mining science and {2. 2010年第6期20卷 913-916页

作者： WANG Ying, TONG Minming, ZHANG Tao school of Information and Electrical engineering, {2. university of mining & technology, Xuzhou 2.1008, {2. [a] school of Information Electrical engineering China University of Mining & Technology Xuzhou 221008 China

Conventional Pd/γ-A12.3 methane sensors are easily poisoned in a sulfur-containing atmosphere, with a subsequent decrease in sensitivity and the working life of methane sensors. We mainly investigated the effect of nanotechnology and a cerium co-catalyst on the stability and anti-sulfur performance of methane sensors. In our experiment, an anti-sulfur methane sensor was prepared by immersing cerium-containing γ-alumina nanometer elements into a Pt-Pd bimetallic nanometer catalyst. The experi- ment about the sensitivity and stability performance of different catalytic methane sensors indicate that sensitivity, decreased by catalyst sulfur poisoning, is improved significantly by adding cerium to the vector. As well, the long-term operational stability of methane sensors increased significantly.

关键词： Cerium anti-sulfur stability sensitivity

Detecting malignant patients via modified boosted tree

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science china(Information sciences) 2010年第7期53卷 1369-1378页

作者： DONG CaiLing1, YIN YiLong1 & YANG XiuKun2.1school of Computer science and {2., Shandong university, Jinan 2.0101, china 2.ollege of Information and Communication, Harbin engineering university, Harbin 150001, china 1. school of Computer science and {2. Shandong University Jinan 250101 China2. College of Information and Communication Harbin Engineering University Harbin 150001 China

As one of the most effective measures to extract useful information from medical database and provide scientific decision-making for diagnosis and treatment of diseases, medical data mining has become an increasingly hot topic in the last few years. Some of the intrinsic characteristics of medical databases, such as the huge volume and imbalanced samples as well as stringent performance standards, make this mining process particularly challenging. By elaborating various challenges existing in Task 1 of KDD Cup 2.08 competition, this paper analyzes some potential solutions to these problems and presents a modified boosted tree as the final classification model. This model ranked the fourth among all the solutions to Task 1. We hope that our analysis and solutions to these challenges would contribute to the development of medical data mining applications.

关键词： classification boosted tree multiple instances scoring Real AdaBoost breast cancer detection medical data mining