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Edaphic factors determining variation of two ecotypes of Leymus chinensis in North China

Progress in Natural Science:Materials International 2006年第11期16卷 1150-1155页

作者： ZHOU Chan~1.and YANG Yunfei~2**(1. MOE key Laboratory of Environmental Change and Natural Disasters, College of Resources Science and Technology, Beijing Normal University, Beijing 1.0875, China 2. key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland Science, Northeast Normal University, Changchun 1.0024, China) [a]MOE key Laboratory of Environmental Change and Natural Disasters College of Resources Science and Technology Beijing Normal University Beijing China [b]key Laboratory of Vegetation Ecology Ministry of Education Institute of Grassland Science Northeast Normal University Changchun China

To identify ecotypic variation of L. chinensis, the physiological characteristics and environmental factors were measured and assessed for grey-green and yellow-green ecotypes of L. chinensis grown in the salt-alkalized and aeolian sandy soils. Although both ecotypes presented a similar salt-alkaline tolerance under the experimental conditions, they differed in several aspects. The L. chinensis grown in the aeolian sandy soils had higher water potential and chlorophyll content and lower proline content in their leaves than those grown in the salt-alkalized habitat, and the grey-green ecotype of L. chinensis in both types of soils had higher water potential, chlorophyll and proline contents than the yellow-green ecotype. Besides, grey-green ecotypes had higher salt-alkaline tolerance than the yellow-green ecotype. The stepwise regression analysis showed that soil conductance and pH value were the main ecological factors affecting the physiology of L. chinensis. From the natural distribution of the two ecotypes, we considered that salt-alkaline in the soils is the leading factor in determining ecotypic variation of L. chinensis. The two ecotypes were first named grey-green and yellow-green ecotypes respectively.

关键词： L.chinensis ecotype adaptability variation ecological factor salt-alkaline in soil.

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Anatexis in Himalayan crust:Evidence from geochemical and chronological investigations of Higher Himalayan Crystallines

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Science China Earth Sciences 2005年第9期48卷 1347-1356页

作者： YANG Xiaosong1. JIN Zhenmin2 & MA Jin1.1. State key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing 1.0029, China 2. Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China 1. State key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration 100029 Beijing China 2. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

Migmatization in Higher Himalayan Crystallines (HHC) results from anatexis. The widely distributed migmatites in HHC are an important clue to investigate the relationship be- tween anatexis and the origins of Higher Himalayan leucogranites (HHL), and to understand the effect of anatexis on crustal evolution during the post-collision period. We studied in detail the chemical features of three basic constituent parts of the migmatites, i.e. leucosome, mesosome and melanosome, and determined the K-Ar ages of leucosomes. Our studies indicate that type-I leucosome is the product of crystallization of melt generated by partial melting of mesosome at source region, but type-II leucosome and HHL probably underwent crystallization differentiation of plagioclase during melt aggregation and migration. The age of 22.67 Ma of Type-I leucosome, which is a little older than the beginning of MCT movement, indicates that anatexis may have played an important role in the formation of MCT. That the ages of type-II leucosome (ranging from 1..82 to 1..37 Ma) are consistent with that of HHL provides new chronological evidence for the relationship between migmatization and HHL. We obtained a very young age of 6.23 Ma of Type-II leucosome that provides new time constraint on magma activity in the central segment of Higher Himalayas.

关键词： Higher Himalayan Crystallines, migmatite, anatexis, leucosome, K-Ar age.

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Rhodium catalyzed asymmetric Pauson-Khand reaction using SDP ligands

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Science China Chemistry 2006年第1期49卷 81-87页

作者： FAN Baomin1. LI Shen2, XIE Jianhua2, WANG, Lixin2, TU Yongqiang1.& ZHOU Qilin2 1. State key Laboratory of Applied Organic Chemistry,Lanzhou University,Lanzhou 730000,China 2. State key Laboratory of Elemento-organic Chemistry,Nankai University,Tianjin 300071. China 1. State key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China 2. State key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China

The activity and enantiocontrol ability of the chiral catalysts prepared from spiro di-phosphine ligands, SDP, and rhodium precursor were investigated in the asymmetric catalytic Pau-son-Khand reaction. The results showed that SDP ligands were very effective in Rh-catalyzed Pau-son-Khand reaction, and their complexes with rhodium could convert a variety of 1.6-enyne compounds into bicyclopentone derivatives under CO atmosphere in high yields with good enantioselec-tivities. The SbF6- was found to be a suitable counter anion of the catalyst, and 1.2-dichloroethane was the best choice of the solvent for Pauson-Khand reaction.

关键词： Pauson-Khand reaction, asymmetric catalysis, diphosphine ligand, rhodium.

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Study on the cluster of floating dross before nucleating during hot-dipping process

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Science China Chemistry 2005年第1期48卷 83-88页

作者： WEI Yunhe1. ZHANG Changqiao1. QIN Jingyu2 & LIU Chengbu1.1. School of Chemistry and Chemical Engineering, Shandong University, Jinan 2501.0, China 2. The key Laboratory of Liquid Structure and Heredity of Materials of Ministry of Education, Shandong University, Jinan 250061. China 1. School of Chemistry and Chemical Engineering Shandong University 250100 Jinan China 2. The key Laboratory of Liquid Structure and Heredity of Materials of Ministry of Education Shandong University 250061 Jinan China

During hot-dipping in molten Zn-55Al, the forming of “floating” dross is closely re- lated with the interaction between the Al and the Fe atoms. Utilizing the thita-thita X-ray diffraction and the Percus-Yevick hard sphere model, this paper investigates the structure of molten Al3Fe that is an approximant of partial melt in practical Zn-55Al alloy melt. It is found that in the melt there exist clusters that resemble the structure of intermetallic compound Al3Fe. The strong in- teraction between Al and Fe atoms is also indicated by the deficiency of the coordination number from 1. and the shrinkage of averaged atomic diameter. Based on such information, it is specu- lated that in the molten Zn-55Al, with the accumulation of Fe, Al3Fe-like clusters form with priority, then grow into dross. On the other hand, after deflating of the effective hard sphere diameter of pure Al atom and enlarging that of the pure Fe atom, the modified model can achieve reasonable fit to the experimental structure factor. Hard sphere modeling also gave a good estimation of the mass density 3.65 g/cm3 of liquid Al3Fe alloy at 1.50℃. Compared with the density of 3.7 g/cm3 of Zn-55Al, the reason for dross floating is satisfactorily understood.

关键词： hot-dipping, dross, Al3Fe alloy, molten structure, P-Y model.

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Grain evolution of nano-crystals ZnO under HP and HT

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Science China(Physics,Mechanics & Astronomy) 2006年第3期49卷 281-290页

作者： SHAO Guangjie1. QIN Xiujuan1. LIU Riping1. WANG Wenkui1.2 & YAO Yushu2 1. key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China 2. Institute of Physics, Chinese Academy of Sciences, Beijing 1.0080, China 1. key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China 2. Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Grain evolution of nano-crystals ZnO under high temperature and pressure is studied using a cubic high pressure apparatus. The structure, grain sizes and morphology of the samples are characterized by X-ray diffraction and field emission scanning electron microscopy. The results show that the grain sizes of ZnO grow rapidly at temperature 200℃ under pressure. At temperature lower than 300 ℃ (including 300 ℃), the grain sizes of the samples first increase with the pressure increasing from 1.to 3 GPa and later de- crease from 4 to 6 GPa. The activation volume from 1.to 3 GPa and from 4 to 6 GPa is calculated respectively using the phenomenological kinetic grain growth equation at temperature 300 ℃. At temperature higher than 400℃ (including 400 ℃), the grain sizes of the samples increase with the pressure increasing from 1.to 6 GPa. ZnO nano-bulks with good quality can be obtained under the specific conditions.

关键词： nano-crystals ZnO,high temperature and pressure,grain evolution

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Tensile and compression properties of Zr-based bulk amorphous alloy at different temperatures

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Science China(Technological Sciences) 2005年第5期48卷 489-495页

作者： WANG Xu1.3, LOU Decheng1. GAO Zhanjun4, LIU Lei1. LIANG Hongmei1. WANG Qingfeng1. LI Qiang1.3 & MA Mingzhen1.2 1. key Laboratory of Metastable Materials Science & Technology of Hebei, Yanshan University, Qinhuangdao 066004, China 2. National key Laboratory for Precision Hot Processing of Metals, Harbin Institute of Technology, Harbin 1.0001. China 3. College of Mechanical Engineering, Yanshan University, Qinhuangdao 066004, China 4. Chinese Academy of Engineering, Beijing 1.0038, China 1. key Laboratory of Metastable Materials Science & Technology of Hebei Yanshan University 066004 Qinhuangdao China 2. College of Mechanical Engineering Yanshan University 066004 Qinhuangdao China 3. Chinese Academy of Engineering 100038 Beijing China 4. National key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology 150001 Harbin China

Mechanical properties of the Zr41.i1.Cu1..5Ni1.Be22.5 bulk amorphous alloy at different temperatures were investigated. The compression test was carried out on a Gleebe-3200 machine at 345 and 375°C, respectively, in the supercooled liquid region. It is shown that decreasing the compressive rate and increasing temperature have a similar influence trend on the compressive behavior of the bulk amorphous alloy. Room and low temperature tensile strengths were tested on the Instron materials testing system. At low temperature, the tensile strength decreased with decreasing of the testing temperature. Hardness measurement indicated that below the glass transition temperature, the hardness decreased with increasing of the annealing temperature and duration time. It, however, increased when the annealing treatment was performed above the glass transition temperature.

关键词： Zr41.i1.Cu1..5Ni1.Be22.5 bulk amorphous alloy, mechanical properties, compressive deformation.

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Pegmatite remote sensing extraction and metallogenic prediction in Azubai area,Xinjiang

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中国有色金属学会会刊：英文版 2011年第S3期21卷 543-548页

作者： PENG Guang-xiong1. 2, YE Zhen-chao1. 2, GAO Guang-ming1. 2, FENG De-shan1. XIONG Yun1.1. School of Geosciences and Info-Physics, Central South University, Changsha 41.083, China 2. key Laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education, Changsha 41.083, China [a] School of Geosciences and Info-Physics Central South University Changsha 410083 China [b] key Laboratory of Metallogenic Prediction of Nonferrous Metals Ministry of Education Changsha 410083 China

Remote sensing technique plays an important role in geological prospecting in Altay because of the remote location and steep terrain with mountains. Pegmatite has important implications for metallogenic prospecting as most of rare metals occurs in it. Pegmatite information from optical and radar images was extracted, and the spatial distribution and scale of pegmatite were generalized in Azubai, Altay. Three mining targets, that is, Halon-Azubai, Kuermutu-Tuyibaguo and Zhuolute-Akuoyige, were delineated based on the analysis of pegmatite information, structure interpretation and other geological data.

关键词： pegmatite remote sensing information extraction metallogenic prediction

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Arbuscular mycorrhizal for-mation of crucifer leaf mus-tard induced by flavonoids apigenin and daidzein

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Chinese Science Bulletin 2004年第12期49卷 1254-1261页

作者： DONG Changjin1.2 & ZHAO Bin1.1. State key Laboratory of Agricultural Microbiology, Huazhong Agri- cultural University, Wuhan 430070, China 2. Department of Biology, Hubei Normal University, Huangshi 435002, China 1. State key Laboratory of Agricultural Microbiology Huazhong Agricultural University 430070 Wuhan China 2. Department of Biology Hubei Normal University 435002 Huangshi China

Flavonoids from legume root secretion may probably act as signal molecules for expression of Rhizobial “nod” nodulation genes and AM fungal symbiotic gene. Leaf mustard is a non-mycorrhizal plant; it does not contain fla- vonoids and other signal molecules. AM fungi could not in- fect the roots of leaf mustard and form a symbiont in nature, when it was treated with flavonoids (apigenin or daidzein). The results of trypan blue staining showed that two kinds of AM fungi (G. intraradices and G. mosseae) successfully in- fected the roots of non-mycorrhizal plant leaf mustard. AM fungi grew towards and colonized the roots of leaf mustard, producing young spores and completing the course of life. AM fungi are the only one kind of fungi with ALP activity. The result of ALP staining has also proved that AM fungi infected successfully the roots of leaf mustard. AM fungi (G. intraradices and G. mosseae) that existed in the roots of non-mycorrhizal plant leaf mustard were probed by nested PCR and special molecular probes. The above-mentioned proof chains have fully proved that flavonoids induced AM fungi (G. intraradices and G. mosseae) to infect non-my- corrhizal plant and establish symbiotic relationship.

关键词：非菌根植物免疫十字花科叶芥菜芹甙元大豆黄酮类黄酮灌木菌根真菌嵌套PCR trypan蓝色染色

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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 University of Mining and Technology, Xuzhou 221.1., China 2. Jiangsu key Laboratory of Resources and Environmental Information Engineering, China University of Mining and Technology, Xuzhou 221.1., 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, 2π] 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

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Wave tectono-sedimentary processes in Tarim basin

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Science China Earth Sciences 2005年第11期48卷 1949-1959页

作者： JIN Zhijun1.2, ZHANG Yiwei1.& CHEN Shuping1.1. key Laboratory for Hydrocarbon Accumulation, Ministry of Education, China University of Petroleum, Beijing 1.2249, China 2. Exploration and Production Research Institute, China Petroleum & Chemical Corporation, Beijing 1.0083, China 1. key Laboratory for Hydrocarbon Accumulation Ministry of Education China University of Petroleum 102249 Beijing China 2. Exploration and Production Research Institute China Petroleum & Chemical Corporation 100083 Beijing China

Based on the unconformities, the formation times of structures, and geological wave filtering applied to basin fills of typical wells around the Manjiaer area in the Tarim basin, the wave tectono-sedimentary processes in the Tarim Basin are discussed. The results of geological wave filtering of basin fills of typical wells show that, in time domain, the evolution of the Tarim basin was controlled by various wave processes with the periods of 740±Ma, 200±Ma, 1.0±Ma and 30±Ma. The analyses of basin fills, basin subsidence and unconformities show that the trends of the sedimentary facies belts, depocenters, and centers of subsidence migrated and interchanged periodically with periods of 200±Ma. These show the propagation of wave movements in space domain. The wave evolution of the Tarim basin is of significance to understanding the formation of the oil and gas reservoirs in the basin.

关键词： Tarim basin, tectonics, sedimentation, crustal undation, wave evolution

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