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Soil formation in bauxite residue: The most promising way to large-scale and ecological disposal

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Journal of Central South University 2019年第2期26卷 265-267页

作者： xue sheng-guo School of Metallurgy and Environment Central South University

Aluminum is an important basic raw material for national economic *** alumina industry has been expanding rapidly due to the increasing demand for *** residue is a highly alkaline solid by-product generated when alumi... 详细信息

关键词： bauxite residue promising way ecological disposal

Revisiting rolling and sliding in two-dimensional discrete element models

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Particuology 2015年第1期13卷 35-41页

作者： Yucang Wang Fernando Alonso-Marroquin sheng xue Jun Xie School of Engineering and Technology.Central Queensland University Earth Science and Resource Engineering The Commonwealth Scientific and Industrial Research Organisation(CSIRO) School of Civil Engineering The University of Sydney

It has long been recognized that the rotation of single particles plays a very important role in simulations of granular flow using the discrete element method （DEM）. Many researchers have also pointed out that the effect of rolling resistance at the contact points should be taken into account in DEM simulations. However, even for the simplest case involving two-dimensional circular particles, there is no agreement on the best way to define roiling and sliding, and different definitions and calculations of rolling and sliding have been proposed. It has even been suggested that a unique rolling and sliding definition is not possible. In this paper we assess results from previous studies on rolling and sliding in discrete element models and find that some researchers have overlooked the effect of particles of different sizes. After considering the particle radius in the derivation of rolling velocity, all results reach the same outcome： a unique solution. We also present a clear and simple derivation and validate our result using cases of rolling. Such a decomposition of relative motion is objective, or independent of the reference frame in which the relative motion is measured.

关键词： Discrete element method Rolling Sliding

Effect of land-use and land-cover change on nutrients in soil in Bashang area,China

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Journal of Environmental Sciences 2003年第4期15卷 548-553页

作者： sheng xue-bin SUN Jian-zhong LIU Yun-xia Research Center for Eco Environmental Sciences Chinese Academy of SciencesBeijing 100085China.

The Bashang area is a water source area and ecological barrier zone for Beijing and Tianjin. The area is located at 200 km from Beijing and Tianjin and is a typical agriculture pasture interlacing zone, in which the eco environment is vulnerable and hence it is sensitive to environmental change. The area is relatively lagged in social and economic development, where the traditional cultivation mode is predominated in agriculture and animal husbandry, but the disturbance by human activity is relatively small. Therefore, in order to reveal the interrelation between eco environmental change in the area and environmental change in Beijing and Tianjin area, it is fairly necessary to study the effect of land use and land cover change on nutrients in soil in this area. According to the actual situation of changed land use for the limited time period, five series of changed land plots were selected and 4 samples were collected from each series for the study. The samples were collected from different soil forming levels at the same site in different time. Analysis of the collected samples indicates that in the process of change of land use and land cover, the nutrients in soil, such as organic matter, total N, total P, total K, and available N, P, K, and B, Mo, Mn, Zn, Cu, and Fe, have regularly changed. When the land had changed from grassland and non irrigated farmland into woodland, and from non irrigated farmland into irrigated field, the nutrients in soil totally increased. But there exists some exception, i.e. quick acting N, P, K, and some microelements have appeared to be inconsistent with the mentioned above regularity in some cases.

关键词： Bashang area land use change variation of nutrients

Energy-limiting factor for coal and gas outburst occurrence in intact coal seam

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International Journal of Mining Science and Technology 2021年第4期31卷 729-742页

作者： Qingyi Tu Yuanping Cheng sheng xue Ting Ren Xiang Cheng State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China Faculty of Safety Engineering China University of Mining and TechnologyXuzhou 221116China School of Civil Mining&Environmental EngineeringUniversity of WollongongNSW 2522Australia

This research reviewed the mechanics and gas desorption properties of intact coal,and tested the crushing work ratios of different intact coals,and then,studied the stress conditions for the failure or crushing of intact coal and the gas demand for the pulverization of intact coal *** a real-life outburst case is examined,the required minimum stress for intact coal outburst is *** study concludes that the crushing work ratios of three intact coal samples vary from 294.3732 to 945.8048 J/m^(2).For the real-life case,more than 2300 MJ of transport work is needed,and 10062.09,7046.57 and 5895.47 m^(3) of gas is required when the gas pressure is 1,2 and 3 MPa,*** crushing work exceeds the transport work and even reaches 13.96 times of the transport *** to provide such an enormous crushing work is an energy-limiting factor for the outburst in intact *** strain energy is needed for the crushing work,and the required minimum stress is over 54.35 MPa,even reaching 300.44 *** minimum stresses far exceed the in-situ vertical and horizontal stresses that can be provided at the 300–700 m mining depth range.

关键词： Coal and gas outburst Intact coal Crushing work ratio Geological factors Outburst energy

Numerical Modeling of Porous Flow in Fractured Rock and Its Applications in Geothermal Energy Extraction

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Journal of Earth Science 2015年第1期26卷 20-27页

作者： Yucang Wang Shimin Wang sheng xue Deepak Adhikary Earth Science and Resource Engineering CSIROKenmore Qld 4069BrisbaneAustralia Key Laboratory of Computational Geodynamics University of Chinese Academy of Sciences

Understanding the characteristics of hydraulic fracture, porous flow and heat transfer in fractured rock is critical for geothermal power generation applications, and numerical simulation can provide a powerful approach for systematically and thoroughly investigating these problems. In this paper, we present a fully coupled solid-fluid code using discrete element method （DEM） and lattice Boltzmann method （LBM）. The DEM with bonded particles is used to model the deformation and fracture in solid, while the LBM is used to model the fluid flow. The two methods are two-way coupled, i.e., the solid part provides a moving boundary condition and transfers momentum to fluid, while the fluid exerts a dragging force to the solid. Two widely used open source codes, the ESyS Particle and the OpenLB, are integrated into one code and paralleled with Message Passing Interface （MPI） library. Some preliminary 2D simulations, including particles moving in a fluid and hydraulic fracturing induced by injection of fluid into a borehole, are carried out to validate the integrated code. The preliminary results indicate that the new code is capable of reproducing the basic features of hydraulic fracture and thus offers a promising tool for multiscale simulation of porous flow and heat transfer in fractured rock.

关键词： discrete element method lattice Boltzmann method hydraulic fracturing geothermalenergy extraction multiscale modelling.

Mining a coal seam below a heating goaf with a force auxiliary ventilation system at Longhua underground coal mine, China

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International Journal of Mining Science and Technology 2015年第1期25卷 67-72页

作者： Wang Gang Xie Jun xue sheng Wang Haiyang State Key Laboratory of Mining Disaster Prevention and Control Shandong University of Science & Technology CSIRO Earth Science and Resource Engineering School of Mining Engineering Taiyuan University of Technology

Extraction of a coal seam which lies not far below a heating goafcan be a major safety challenge. A force auxiliary ventilation system was adopted as a control method in successful extraction and recovery of the panel 30110 of the #3-1 coal seam, which is about 30-40 rn below the heating goaf of the #2-2 seam at Longhua underground coal mine, Shanxi Province, China. Booster fans and ventilation control devices such as doors and regulators were used in the system. The results show that, provided that a force auxiliary ventilation system is properly designed to achieve a pressure balance between a panel and its overlying goat＇, the system can be used to extract a coal seam overlain by a heating goal. This paper describes the design, installation and performance of the ventilation system during the extraction and recovery phases of the oanel 30110.

关键词： Force auxiliary ventilation systemMining under a heating goafMultiple seams of close spacingPressure balance

Gel fire suppressants for controlling underground heating

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Journal of Coal Science & Engineering(China) 2011年第3期17卷 256-264页

作者： HU sheng-gen xue sheng Energy Technology Commonwealth Scientific and Industrial Research Organisation Newcastle NSW 2300 Australia Exploration and Mining Commonwealth Scientific and Industrial Research Organisation Kenmore QLD 4069 Australia

One of the major safety issues in coal mining is heatings and the resultant spontaneous combustion in underground coal mines. CSIRO researchers have developed a number of polymer gels suitable for controlling beatings in coal mines. These gels were developed to meet strict selection criteria including easy preparation, no or low toxicity, controllable gelation time, adaptable to mine water chemistry, adjustable viscosity, relatively long gel life, thermally and chemically stable and low cost. The HPAM-Aluminum Citrate gel system was identified to be the most favourable gel system for fire suppression in under- ground coal mines. These gels can be applied to the areas undergoing coal heating or gas leakage at a controllable gelation time and impermeable gel barriers can be formed in the areas to block ingress of air.

关键词： underground heating gel barrier gel preparation gelation time

Fully Biodegradable Poly(lactic acid)/Poly(propylene carbonate)Shape Memory Materials with Low Recovery Temperature Based on in situ Compatibilization by Dicumyl Peroxide

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Chinese Journal of Polymer Science 2018年第6期36卷 783-790页

作者： sheng-xue Qin Cui-Xiang Yu xue-Yang Chen Hai-Ping Zhou Li-Fen Zhao College of Mechanical and Electric Engineering College of Materials Science and EngineeringShandong University of Science and TechnologyQingdao 266590China Qingdao Reinforced Thermoplastic Pipes Engineering Technology Center Qingdao 266590China

Fully biodegradable blends with low shape memory recovery temperature were obtained based on poly（lactic acid）（PLA） and poly（propylene carbonate）（PPC）. By virtue of their similar chemical structures, in situ cross-linking reaction initiated by dicumyl peroxide（DCP） between PLA and PPC chains was realized in PLA/PPC blends. Therefore, the compatibility between PLA and PPC was increased, which obviously changed the phase structures and increased the elongation at break of the blends. The compatibilized blends had a recovery performance at 45 °C. Combining the changes of phase structures, the mechanism of the shape memory was discussed. It was demonstrated that in situ compatibilization by dicumyl peroxide was effective to obtain eco-friendly PLA/PPC blends with good mechanical and shape memory properties.

关键词： Polylactide Poly(propylene carbonate) Dicumyl peroxide Compatibilization Shape memory

A Global-Scale Image Lossless Compression Method Based on QTM Pixels

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Journal of China University of Mining and Technology 2006年第4期16卷 466-469页

作者： SUN Wen-bin ZHAO xue-sheng Department of Surveying and Land Science China University of Mining ＆ Technology Beijing 100083 China National Geometrics Center of China Beijing 100044 China

In this paper, a new predictive model, adapted to QTM (Quaternary Triangular Mesh) pixel compression, is introduced. Our approach starts with the principles of proposed predictive models based on available QTM neighbor pixels. An algorithm of ascertaining available QTM neighbors is also proposed. Then, the method for reducing space complexities in the procedure of predicting QTM pixel values is presented. Next, the structure for storing compressed QTM pixel is proposed. In the end, the experiment on comparing compression ratio of this method with other methods is carried out by using three wave bands data of 1 km resolution of NOAA images in China. The results indicate that: 1) the compression method performs better than any other, such as Run Length Coding, Arithmetic Coding, Huffman Cod- ing, etc; 2) the average size of compressed three wave band data based on the neighbor QTM pixel predictive model is 31.58% of the origin space requirements and 67.5% of Arithmetic Coding without predictive model.

关键词： Quaternary Triangular Mesh lossless compression predictive model image entropy