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Journal of Computational Mathematics 2000年第5期18卷 513-520页

作者： Yan Gao (Department of Basic Science, china university of mining and technology-beijing, beijing 100083, china) （北京）中国矿业大学北京 100083

This paper refers to Clarke generalized gradient for a smooth composition of max-type functions of the form: f(x) = g(x, maxj∈J1 f1j(x),''', maxj∈Jm fmj(x)), where x ∈Rn, Ji, i = 1,''',m are finite index sets, g and fij,j ∈ Ji, i = 1,... )m, are continuously differentiable on Rm+n and Rn, respectively. In a previous paper) we proposed an algorithm of finding an element of Clarke generalized gradient for f, at a point. In that paper, finding an element of Clarke generalized gradient for f, at a point, is implemented by determining the compatibilities of systems of linear inequalities many times. So its computational amount is very expensive. In this paper) we will modify the algorithm to reduce the times that the compatibilities of systems of linear inequalities have to be determined.

关键词： Nonsmooth optimization Clarke generalized gradient Max-type function.

Environmental benefits of underground coal gasification

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Journal of Environmental Sciences 2002年第2期14卷 284-288页

作者： LIU Shu qin, LIU Jun hua, YU LI (china university of mining & technology, beijing 100083, china. china university of mining & technology Beijing 100083 Chin

Environmental benefits of underground coal gasification are evaluated. The results showed that through underground coal gasification, gangue discharge is eliminated, sulfur emission is reduced, and the amount of ash, mercury, and tar discharge are decreased. Moreover, effect of underground gasification on underground water is analyzed and CO 2 disposal method is put forward.

关键词： environmental benefits coal underground coal gasification

Effect of activation agents on the surface chemical properties and desulphurization performance of activated carbon

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Science china(Technological Sciences) 2010年第9期53卷 2515-2520页

作者： ZHANG XiangLan,ZHANG Yan,WANG ShuangSheng,ZHANG JingJing & ZHOU Wei School of Chemical and Environmental Engineering,china university of mining and technology (beijing),beijing 100083,china 1. School of Chemical and Environmental Engineering China University of Mining and Technology (Beijing) Beijing 100083 China

Flue gas pollution is a serious environmental problem that needs to be solved for the sustainable development of *** surface chemical properties of carbon have great influence on its desulphurization performance.A series of activated carbons (ACs) were prepared using HNO3,H2O2,NH3·H2O and steam as activation agents with the aim to introduce functional groups to carbon surface in the ACs preparation *** ACs were physically and chemically characterized by iodine and SO2 adsorption,ultimate analysis,Boehm titration,and temperature-programmed reduction (TPR).Results showed that the iodine number and desulphurization capacity of NH3·H2O activated carbon (AC-NH3) increase with both activation time,and its desulphurization capacity also increases with the concentration of activation ***,HNO3 activated carbon (AC-HNO3) and H2O2 activated carbon (AC-H2O2) exhibit more complex *** their iodine numbers increase monotonously with activation *** with steam activated AC (AC-H2O),the nitrogen content increases 0.232% in AC-NH3 and 0.077% in *** amount of total basic site on AC-HNO3 is 0.19 mmol·g-1 higher than that on AC-H2O.H2O2 activation introduces an additional 0.08 mmol·g-1 carboxyl groups to AC surface than that introduced by steam *** desulphurization capacity of ACs in simulate flue gas desulphurization decreases as follows: AC-NH3 > AC-HNO3 > AC-H2O2 > *** sequence is in accord with the SO2 catalytic oxidation/oxidation ratio in the absence of oxygen and the oxidation property reflected by *** the presence of oxygen,all adsorbed SO2 on ACs can be oxidized into *** desulphurization capacity increases differently according to the activation agents;the desulphurization capacity of AC-NH3 and AC-HNO3 improves by 4.8 times,yet AC-H2O increases only by 2.62 as compared with the desulphurization of corresponding ACs in absence of oxygen.

关键词： activated carbon activation agent surface chemical property desulphurization TPR

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 university, beijing 100875, china Department of Mathematics, Linyi Normal university, Linyi 276005, 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.

On three-dimensional geological modeling and visualization

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Science china Earth Sciences 2004年第8期47卷 739-748页

作者： WU Qiang1 & XU Hua2 1. Department of Resource Exploitation Engineering, china university of mining and technology, beijing 100083, china 2. beijing Institute of Petrochemical technology, beijing 102617, china 1. Department of Resource Exploitation Engineering China University of Mining and Technology 100083 Beijing China 2. beijing Institute of Petrochemical technology 102617 Beijing China

The technology of 3D geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3D geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3D geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3D dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3D geological modeling,geometrical model,system architecture,visualization

Thermal-mechanical coupled effect on fracture mechanism and plastic characteristics of sandstone

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Science china(Technological Sciences) 2007年第6期50卷 833-843页

作者： ZUO JianPing1,2, XIE HePing2,3, ZHOU HongWei1,2 PENG SuPing1 1 State Key Laboratory of Coal Resources and Safe mining, china university of mining and technology, beijing 100083, china 2 Institute of Rock Mechanics and Fractals, china university of mining and technology, beijing 100083, china 3 Sichuan university, Chengdu 610065, china 1. State Key Laboratory of Coal Resources and Safe mining China University of Mining and Technology Beijing 100083 China 2. Institute of Rock Mechanics and Fractals China University of Mining and Technology Beijing 100083 China 3. Sichuan university Chengdu 610065 China

Scanning electronic microscopy (SEM) was employed to investigate fractographs of sandstone in mine roof strata under thermal-mechanical coupled effect. Based on the evolution of sandstone surface morphology in the failure process and frac- tography, the fracture mechanism was studied and classified under meso and mi- cro scales, respectively. The differences between fractographs under different tem- peratures were examined in detail. Under high temperature, fatigue fracture and plastic deformation occurred in the fracture surface. Therefore, the temperature was manifested by these phenomena to influence strongly on micro failure mechanism of sandstone. In addition, the failure mechanism would transit from brittle failure mechanism at low temperature to coupled brittle-ductile failure mechanism at high temperature. The variation of sandstone strength under differ- ent temperature can be attributed to the occurrence of plastic deformation, fatigue fracture, and microcracking. The fatigue striations in the fracture surfaces under high temperature may be interpreted as micro fold. And the coupled effect of tem- perature and tensile stress may be another formation mechanism of micro fold in geology.

关键词： sandstone, thermal-mechanical coupled effects, fractograph, plastic deformation, SEM, micro fold

Molecular mechanism of dehydrin in response to environmental stress in plant

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Progress in Natural Science:Materials International 2007年第3期17卷 237-246页

作者： ZHANG Yuxiu , WANG Zi and XU Jin (Department of Bioengineering, School of Chemical and Environmental Engineering, china university of mining and technology (beijing), beijing 100083, china Department of Biology, Graduate university of Chinese Academy of Sciences, beijing 100049, china) [a]Department of Bioengineering School of Chemical and Environmental Engineering China University of Mining and Technology (Beiing) Beijing China [b]Department of Biology Graduate University of Chinese Academy of Sciences Beijing China

Dehydrins, known as the D-11 subgroup of late embryogenesis abundant (LEA) protein, are an immunologically distinct family of proteins, which typically accumulate in desiccation-tolerant seed embryo or in vegetative tissues in response to various environmental stresses such as drought, salinity and freezing. The existence of conservative sequences designated as K, S, and Y segments is a structural feature of dehydrins, and the K segment found in all dehydrins represents a highly conserved 15 amino acid motif (EKKGIMDKIKEKLPG) and forms an amphiphilicα-helix. According to the arrangement of these domains and clustering analysis, dehydrins are subdivided into 5 subtypes: YnSK, Kn, KnS, SKn and YnK. Different types of dehydrins are induced by different environmental stress in plants. Study results showed that dehydrins might play important protective roles under abiotic stress via a number of different mechanisms, including improving or protecting enzyme activities by the cryoprotective activity in responding to freeze/thaw or dehydration; stabilizing vesicles or other endomembrane structures by function as the membrane stabilizer during freeze induced dehydration, and preventing the membrane system from the oxidative damage induced by reactive oxygen radicals as the radical scavenger. Here, the gene expression and molecular mechanisms of dehydrin in response to stress in plants are discussed.

关键词： dehydrin stress mechanism.

Deformation mechanism and excavation process of large span intersection within deep soft rock roadway

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mining Science and technology 2010年第1期20卷 28-34页

作者： LI Guofeng, HE Manchao, ZHANG Guofeng, TAO Zhigang Institute of Geotechnical Engineering, china university of mining & technology, beijing 100083, china [a] Institute of Geotechnical Engineering China University of Mining & Technology Beijing 100083 China

The FLAC3D software was used to simulate and analyze numerically the displacement, stress and plastic zone distribu-tion characteristics of a large span intersection in a deep soft rock roadway after the surrounding rock was excavated. Our simula-tion results show that there are two kinds of dominating factors affecting roadway stability at points of intersection, one is the angle between horizontal stress and axial direction of the roadway and the other are the angles at the points of intersection. These results are based on a study we carried out as follows: first, we analyzed the failure mechanism of a large span intersection and then we built a mechanical model of a rock pillar at one of the points of intersection. At the end of this analysis, we obtained the failure characteristics of the critical parts on the large span intersection. Given these failure characteristics, we proposed a new supporting method, i.e., a Double-Bolt Control technology (DBCT). By way of numerical simulation, DBCT can effectively control the deformation of the surrounding rock at the points of intersection in roadways.

关键词： deep soft rock junction numerical simulation

Water distribution extracted from mining subsidence area using Kriging interpolation algorithm

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中国有色金属学会会刊：英文版 2011年第S3期21卷 723-726页

作者： DAI Hua-yang, REN Li-yan, WANG Meng, XUE Hai-bing College of Geosicence and Surveying Engineering, china university of mining & technology, beijing 100083, china College of Geosicence and Surveying Engineering China University of Mining & Technology Beijing 100083 China

By comprehensively analyzing the data of geology and mining, Kriging algorithm was introduced to analyze the thematic information of geological data, to rapidly extract mining parameters for predicting mining subsidence, and to effectively integrate geomorphology and predict information. As a result, the change information of water body is successfully detected from the prediction of surface subsidence due to mining activity. Analysis shows that the elevation of farmland in the west side of water body will be lower than ever, and the west part farmland will be submerged. However, there is no evidence for impacting the villages. All the information provides a reference for efficiently assessing environmental impact due to mining activity, which can help to govern the subsidence of the area reasonably.

关键词： Kriging interpolation water body mining subsidence prediction parameters data fusion

Process optimization of reaction of acid leaching residue of asbestos tailing and sodium hydroxide aqueous solution

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Science china(Technological Sciences) 2009年第1期52卷 204-209页

作者： DU GaoXiang1,3, ZHENG ShuiLin2 & DING Hao1 1 School of Materials Science and technology, china university of Geosciences (beijing), beijing, 100083, china 2 School of Chemical and Environment Engineering, china university of mining and technology (beijing), beijing 100083, china 3 Hebei Qinghe Refractory Group Co. Ltd., Xingtai 054804, china 1. School of Materials Science and technology China University of Geosciences (Beijing) Beijing 100083 China 3. Hebei Qinghe Refractory Group Co. Ltd. Xingtai 054804 China 2. School of Chemical and Environment Engineering China University of Mining and Technology (Beijing) Beijing 100083 China

Silica is the major component of the acid leaching residue of asbestos tailing. The waterglass solution can be prepared by the reaction of the residue with sodium hydroxide aqueous solution. Compared to the high temperature reaction method, this process is environmental friendly and low cost. In this paper, the reaction process of the residue and the sodium hydroxide aqueous solution is optimized. The optimum reaction process parameters are as follows: the usage of sodium hydroxide is 26.4 g/100 g acid leaching residue, the reaction temperature is 90℃, the reaction time is 1 h, and the ratio of the liquid/solid is 2.0. The significance sequence of the process parameters to the alkali leaching reaction effect is the usage of sodium hydroxide > the ratio of the liquid/solid > the reaction time > the reaction temperature. The significance sequence to the leaching ratio of SiO2 is the ratio of the liquid/solid > the usage of sodium hydroxide > the reaction time > the reaction temperature. The significance sequence to the modulus of the sodium silicate is the ratio of the liquid/solid > the usage of sodium hydroxide > the reaction time > the reaction temperature. Under the optimum conditions, the leaching ratio of the SiO2 is 77.5%, and the modulus of the sodium silicate is 3.15. The XRD analysis result indicates that the major components of the alkali leaching residue are serpentine, talc, quartz and some albite.

关键词： asbestos tailing acid leaching residue sodium hydroxide process optimization