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Journal of Systematics and Evolution 2009年第3期47卷 191-201页

作者： 1Zhihua JIAO 2,3Jianhua LI 1(School of Chemical and Environmental Engineering, china university of mining and technology, beijing 100083, china) 2(The Arnold Arboretum of Harvard university, Cambridge, MA 02138, USA) 3(Adjunct Faculty of College of Life Sciences, Zhejiang university, Hangzhou 310029, china) (Adjunct Faculty of College of Life Sciences Zhejiang University Hangzhou 310029 China)

Pachysandra is an eastern Asian-North American disjunct genus with three species, two in eastern Asia (Pachysandra axillaris and Pachysandra terminalis) and one in eastern North America (Pachysandra procumbens). Although morphological and cytological studies suggest a close affinity of P. procumbens with P. axillaris, molecular data from nuclear and chloroplast DNA regions have provided conflicting signals. In this study, we tested previous phylogenetic hypotheses using sequences of nuclear ribosomal DNA internal transcribed spacers and chloroplast ndhF gene from multiple individuals of each of the three species. We also estimated the time of divergence between eastern Asia and eastern North America. Our results support the morphological and cytological conclusion that P. procumbens is more closely related to P. axillaris than to P. terminalis. The estimated time of divergence of P. axillaris and P. procumbens was 14.6±5.5 mya, consistent with estimates from many other eastern Asian-North American disjunct genera. The migration of Pachysandra populations from eastern Asia to North America might have occurred by way of the North Atlantic land bridge.

关键词： Buxaceae divergence time ndhF nrDNA ITS Pachysandra.

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软岩巷道锚喷网支护参数的合理确定

湘潭矿业学院学报 1997年第4期12卷 11-16页

作者：刘社育赵国堂中国矿业大学北京研究生部北京100083 铁道部科学研究院北京100081

通过对大量现场实测资料的分析 ,给出了软岩巷道围岩区域拉压变形机制以及应用压缩区域自承能力和控制张拉域变形的支护原理 ,针对不同尺寸的张拉域和压缩域 ,提出了采用深锚和锚杆群组合作用的锚喷网支护方法 ,介绍了不同支护工艺下支... 详细信息

通过对大量现场实测资料的分析 ,给出了软岩巷道围岩区域拉压变形机制以及应用压缩区域自承能力和控制张拉域变形的支护原理 ,针对不同尺寸的张拉域和压缩域 ,提出了采用深锚和锚杆群组合作用的锚喷网支护方法 ,介绍了不同支护工艺下支护参数的计算与选择。图 2 ,表 1 ,参 7。

关键词：软岩巷道区域拉压锚喷网支护支护参数

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地热单井回灌渗流场理论研究

太阳能学报 2003年第2期24卷 197-201页

作者：何满潮刘斌姚磊华徐能雄中国矿业大学力学与建筑工程学院中国地质大学工程技术学院北京100083 中国地质大学工程技术学院

在地热开发过程中经常遇到如下问题 :热储压力随开采量和时间的增加而降低 ,地热尾水排放造成热污染和资源浪费等。回灌是解决上述问题的有效方法。针对回灌过程中渗流场的动态变化 ,建立地热回灌渗流场数学模型 ,推导了渗透系数恒定与... 详细信息

在地热开发过程中经常遇到如下问题 :热储压力随开采量和时间的增加而降低 ,地热尾水排放造成热污染和资源浪费等。回灌是解决上述问题的有效方法。针对回灌过程中渗流场的动态变化 ,建立地热回灌渗流场数学模型 ,推导了渗透系数恒定与变化时不同条件下的单井回灌公式。实例分析表明 :所得公式能够表征回灌渗流场中各变量之间的相互关系 ,可以解释和预测回灌过程中水头与流量的变化趋势。

关键词：地热单井回灌渗流场模型

RESEARCH ON THE SAFETY GUARANTEE OPERATION SYSTEM OF COAL CORPORATE IN china

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RESEARCH ON THE SAFETY GUARANTEE OPERATION SYSTEM OF COAL CO...

Removal of Volatile Organic Compounds by Adsorption and Photocatalytic Oxydation

2005年中国机械工程学会年会

作者： YANG Guang , YANG Yongqing, XIAO Ye ( Shandong Institute of Business and technology, Yantai, 264005 china university of mining and technology, beijing, 100083)

＜正＞The present safety situation of coal corporate in china is serious. To change the passive situation needs reforming and innovating the safety production administration system. According to the advanced foreign experiences, the scientific concept of development, and modern management ideas, a more effective and scientific, legal safety guarantee operation system was proposed in this paper. It indicates that safety production is the core of such system, and views that mining corporate should depend on not only itself management but also government, insurance company, coal association and medium agency together to guarantee safety production of coal corporate. The establishment of safety guarantee operation system can drive coal corporate to promote safety production input, strengthen safety management and prevent accident effectively. The research results proved that corporate safety production can form positive interaction system and realize "Double Win", at the same time provide significant referential value for government to improve coal corporate safety situations.

关键词： mining corporate safety production guarantee system

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Journal of Wuhan university of technology(Materials Science) 2007年第3期22卷 450-452页

作者：许德平黄正宏 Lab of Advanced Materials Department of Materials Science and EngineeringTsinghua University School of Chemical and Environmental Engineering China University of Mining and Technology

Based on the study of equilibrium adsorption on viscose rayon-based activated carbon fiber （ACF） by gravimetric method, mounting of TiO2 on PAN-based activated carbon cloth （ACC） and their photocatalytic activity as well as adsorption performance for benzene were investigated. The crystallinity of TiO2 and pore structure were characterized by XRD and N2 adsorption. The results show that crystallinity of TiO2 and pore structure could be postulated by heat treatment condition. Both crystallinity of TiO2 and pore structure of hybrid have effects on photocatalytic performance of TiO2-mounted ACC. It would be more attractive and prospective for the combination of TiO2 photocatalytic activity and adsorption ability of porous materials.

关键词： volatile organic compounds activated carbon cloth TiO2

Dispersion of Co-poly Carboxylate Superplasticizer Containing Poiyether Side Chain

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Journal of Wuhan university of technology(Materials Science) 2006年第Z1期21卷 132-135页

作者：左彦峰王栋民 china university of mining and technology (beijing District) beijing 100083 China

Free radical co-polymerization was employed to synthesize co-poly carboxylate (PC) su-perplasticizers with different amount of carboxyl and methyl polyethylene glycol (MPEG) side chain. Dispersion ability and retention of PC were compared with one another. The results show that increase of side chain is advantageous to dispersion, but it decreases when amount of MPEG is beyond a certain value which is different with the proportion of carboxyl. If the amount of carboxyl increases, the influence of side chain in copolymer on dispersion diminishes. Polyether side chain is advantageous to retention. And the author explained the mechanism of PC using the theory of steric repulsive force.

关键词： co-poly carboxylate superplasticizer disperse fresh cement paste steric repulsive force

Tourism Destination Eco-Security and its Dynamic Evaluation Method

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Tourism Destination Eco-Security and its Dynamic Evaluation ...

Sequence Stratigraphy and Paleogeography of the Early and Early Middle Jurassic Coal Measures in the Turpan-Hami Basin,Northwestern china

2006（沈阳）国际安全科学与技术学术研讨会

作者： YANG Zhuquan, TANG Shilu Institute of Land Reclamation and Ecology Restoration, china university of mining and technology, beijing 100083, china College of Tourism, Guilin university of technology, Guilin 541004, china

＜正＞Ecological security of tourism destination is an important factor for the sustainable development of tourism industry. Currently , various ecological problems seriously threaten many tourism destinations. A complete understanding of eco - security situation is the foundation of maintaining sustainable development for tourism destination. However, the study of tourism destination eco - security is still in its initial stage, basing on the references at home and abroad, the connotation and dynamic characteristics of tourism destination eco - security were discussed. Then, the research of the evaluation method of tourism destination eco - security are carried out, and the standard system, evaluation mode, trend analyze mode, and the dynamic evaluation method of tourism destination eco - safety which is based on the situation evaluation and trend analyze, are put forwds.

关键词： tourism destination eco - security P - S - R mode dynamic evaluation

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地学前缘 2009年第S1期16卷 156-156页

作者： Di Gao,Longyi Shao,Zhong Luo Department of Resources and Earth Sciences,china university of mining and technology(beijing),beijing 100083,china.

This paper analyses the sequence stratigraphy and palaeogeography of the Early and early Middle Jurassic coal measures in the Turpan-Hami Basin, northwestern *** controls of the palaeogeography and sequence stratigraphy on the coal accumulation in this basin have been *** results show that the coal measures were formed in a fluvial-delta-lacustrine sedimentary system,and a total of 4 third-order sequences were developed,

关键词： lithofacies palaeogeography coal accumulation sequence stratigraphy Jurassic Turpan-Hami Basin

Classification of Coalbed Methane Enrichment Units of Qinshui Basin Based on Geological Dynamical Conditions

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地学前缘 2009年第S1期16卷 155-155页

作者： Gang Xu,Wenfeng Du,Xubiao Deng State Key Laboratory of Coal Resources and Safe mining,china university of mining and technology(beijing),beijing 100083, china.

Coalbed methane enrichment will be controlled by many good macro geological dynamical conditions; there is evident difference of enrichment grade in different area and different geological *** paper has studied tectonic dynamical conditions, thermal dynamical conditions and hydraulic conditions, which affect coalbed methane enrichment in Qinshui *** methane enrichment units have been divided based on tectonic dynamical conditions of Qinshui basin,combined with thermal dynamical conditions and hydraulic conditions.

关键词： geological dynamical conditions Qinshui basin coalbed methane enrichment units classifications