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Some basic concepts and problems on the petrogenesis of intra-plate ocean island basalts

Chinese Science Bulletin 2009年第22期54卷 4148-4160页

作者： NIU Yaoling1,2.3 1 Department of Earth Sciences, Durham university, Durham DH1 3LE, UK 2.School of Earth Sciences and Resources, china university of Geosciences, Beijing 100083, china 3 School of Earth and Space Sciences, Peking university, Beijing 100871, china Department of Earth Sciences Durham University Durham DH1 3LE UK School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China School of Earth and Space Sciences Peking University Beijing 100871 China

Basaltic magmatism that builds intra-plate ocean islands is often considered to be genetically associated with "hotspots" or "mantle plumes". While there have been many discussions on why ocean island basalts (OIB) are geochemically highly enriched as an integral part of the mantle plume hypothesis, our current understanding on the origin of OIB source material remains unsatisfactory, and some prevailing ideas need revision. One of the most popular views states that OIB source material is recycled oceanic crust (ROC). Among many problems with the ROC model, the ocean crust is simply too depleted (e.g., [La/Sm]PM > 1) OIB. Another popular view states that the enriched component of OIB comes from recycled continental crust (RCC, i.e.; terrigenous sediments). While both CC and OIB are enriched in many incompatible elements (e.g., both have [La/Sm]PM >>1), the CC has characteristic enrichment in Pb and deletion in Nb, Ta, P and Ti. Such signature is too strong to be eliminated such that CC is unsuitable as source material for OIB. Plate tectonics and mantle circulation permit the presence of ROC and RCC materials in mantle source regions of basalts, but they must be volumetrically insignificant in contributing to basalt magmatism. The observation that OIB are not only enriched in incompatible elements, but also enriched in the progressively more incompatible elements indicates that the enriched component of OIB is of magmatic origin and most likely associated with low-degree melt metasomatism. H2. and CO2.rich incipient melt may form in the seismic low velocity zone (LVZ). This melt will rise because of buoyancy and concentrate into a melt rich layer atop the LVZ to metasomatize the growing lithosphere, forming the metasomatic vein lithologies. Erupted OIB melts may have three components: (1) fertile OIB source material from depth that is dominant, (2. the melt layer, and (3) assimilation of the metasomatic

关键词：岩石成因论海洋 OIB 矿物学

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Biodegradable amphiphilic block copolymers containing functionalized PEO blocks:Controlled synthesis and biomedical potentials

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Science china Chemistry 2010年第3期53卷 519-527页

作者： ZHANG Yu1,2.SUN PeiJian1,2.& GAN ZhiHua1 1CAS Key Laboratory of Engineering Plastics,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,china 2.raduate university of Chinese Academy of Sciences,Beijing 100039,china CAS Key Laboratory of Engineering Plastics Institute of Chemistry Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of Sciences Beijing China

A series of controllable amphiphilic block copolymers composed of poly(ethylene oxide)(PEO) as the hydrophilic block and poly(ε-caprolactone)(PCL) as the hydrophobic block with the amino terminal group at the end of the PEO chain(PCL-b-PEO-NH2. were *** on the further reaction of reactive amino groups,diblock copolymers with functional carboxyl groups(PCL-b-PEO-COOH) and functional compounds RGD(PCL-b-PEO-RGD) as well as the triblock copolymers with thermosensitive PNIPAAm blocks(PCL-b-PEO-b-PNIPAAM) were *** well-controlled structures of these copolymers with functional groups and blocks were characterized by gel permeation chromatography(GPC) and 1H NMR *** copolymers with functionalized hydrophilic blocks were fabricated into microspheres for the examination of biofunctions via cell culture experiments and in vitro drug *** results indicated the significance of introducing functional groups(e.g.,NH2.COOH and RGD) into the end of the hydrophilic block of amphiphilic block copolymers for biomedical potentials in tissue engineering and controlled drug release.

关键词： amphiphilic block copolymers biodegradable polymers functional terminal group cell growth drug release

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Research on Vibration Cutting Performance of Particle Reinforced Metallic Matrix Composites SiC_p/Al

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厦门大学学报（自然科学版） 2002年第S1期41卷 70-71页

作者： ZHAO Bo 1,2. LIU Chuan-shao 2. ZHU Xun-sheng 1, XU Ke-wei 1 (1. Institute of Mechanical Engineering, Shanghai Jiaotong U niversity, Shanghai 2.0030, china 2. Department of Mechanical Engineering, Jiaozuo Institute of technology, Hena n 454000, china)

The cutting performance of particle reinforced meta ll ic matrix composites (PRMMCs) SiC p/Al in ultrasonic vibration cutting and comm on cutting with carbide tools and PCD tools was experimentally researched in the paper. The changing rules of chip shape, deformation coefficient, shear angle a nd surface residual stress were presented by ultrasonic vibration cutting. Resul ts show: when adopting common cutting, spiral chip with smaller curl radius will be obtained. The chip with zigzag contour is short and thick. There are lots of sheet cracking both on the face of the chip and on the machined surface. That i s to say, the cutting process of metallic matrix composites(MMCs) is not all lik e the cutting process of plastic material. It is akin to the breaking process of brittle material. By comparison, when adopting ultrasonic cutting, because tool contacts with workpiece intermittently in high frequency, deformation of chip i s small, loose spiral chip with larger curl radius is long and thin. The phenome non is just similar to vibration cutting of plastic material. But the chip still belongs to plastic or semi-plastic segmental chip due to the structure charact eristics of the material itself. Furthermore, the tangential residual compressio n stress of vibration cutting is larger than that of common cutting, axial resid ual stress has a relation to the feed rate and residual stress does not changes obviously with cutting depth and they are in the same order of magnitude on the whole. According to the test result analyzing, the following conclusions are put forward: 1) The extruding deformation is serious in common cutting PRMMCs, defo rmation of it’s chip is larger, and the chip with lesser curl radius is short. Whereas, the deformation of chip in vibration cutting PRMMCs is lesser, the curl radius is bigger, and the loose chips are obtained at every turn. 2. The cuttin g deformation coefficient of chip in vibration cutting is lesser than that in co mmon cutting, h

关键词： PRMMCs ultrasonic vibration cutting chip deform ation chip shape

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CALIS联合目录数据库的质量控制

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图书馆论坛 2004年第4期24卷 90-92页

作者：万荣花华南理工大学图书馆广东广州510640

分析了当前CALIS联合目录数据库的质量问题。

关键词： CALIS “中国高等教育文献保障系统” 联合目录数据库质量控制

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Application of the Algorithm of Fractional Dimension to Extraction Image Edge

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稀有金属材料与工程 2006年第S3期 605-606页

作者： Qiang Luo~1 Qingli Ren~(2.3) (1.The Second Artillery Engineering college,Xi'an 71002.,china) (2.School of Technical Physics,Xidian {2.,Xi'an 710071,china) (3.Xi'an Jiaotong {2.,Xi'an 710049,china)

The idea of fractional dimension was stated in brief ***,adopting the fractional statistical similar principle, the method of the least square minimum error was applied to evaluate the fractional dimension of per image pixel depending on the fractional property of *** the image edge is extracted by magnitude of fractional dimension of image *** presented the algorithm of the local fractional dimension,which made the rule of window size and sentencing the fractional dimension of *** this algorithm was waste time,it is better than the classical ones in extraction edge and anti-jamming.

关键词： fractional dimension image edge fractional Brownian random field

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Analysis on Dam-Breaking Mode of Tangjiashan Barrier Dam in Beichuan County

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Journal of Mountain Science 2011年第2期8卷 354-362页

作者： HU Xiewen LUO Gang LV Xiaoping HUANG Runqiu SHI Yubin Faculty of Geosciences and Environmental Engineering Southwest Jiaotong University Chengdu 610031 China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China Aseismic Engineering technology Key Laboratory of Sichuan Province Southwest Jiaotong UniversityChengdu 610031 China Chengdu Hydroelectric Investigation and Design Institute China Hydropower Consulting Group Chengdu 610072 China

Tangjiashan landslide is a typical high-speed consequent landslide of medium-steep dip angle. This landslide triggered by earthquake took place in about semi-minute. The relative sliding displacement is 900 meters, so average sliding speed is about 30 meters per second. The longitudinal length of barrier dam which is formed by high-speed landslide along river is 803.4 meters; and maximum width crossing river is 611.8 meters. And its volume is estimated about 2..37 million steres. Through detailed geological investigation of the barrier dam, together with early geological information before earthquake, geological structures of the barrier dam and its stability of upstream and downstream slopes are studied when water level reaches different elevations in condition of continual after shocks with seismic intensity of 7 or 8 Richter scale. On this basis, dam-breaking mode of barrier dam is discussed deeply. Thereby, analytic results provide significant guidance and advices to front headquarters of Tangjiashan barrier dam, so that some proper engineering measures can be implemented and flood discharge can be carried out well.

关键词： Tangjiashan Barrier Dam High-speed landslide Blocking river Dam-breaking

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Electrochemical behaviour of commercially pure titanium and Co-Cr alloy in Ringer's solution

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Rare Metals 2002年第4期21卷 266-270页

作者： LIANG Chenghao and MOU ThanqiSchool of Chemical Engineering, Dalian university of technology, Dalian 116012. {2. School of Chemical Engineering Dalian University of Technology Dalian 116012

The electrochemical behaviors of commercially pure titanium (CP Ti) and Co-Cralloy in Ringer's solution have been investigated. The results indicate that the electric potentialof passive region for CP Ti is up to 3000 mV, and its passive current density is 3.078 μA/cm^*** excellent corrosion resistance of CP Ti can be attributed to the formation of TiO_2.oxide *** passive region of Co-Cr alloy is 770 mV, which is narrower than that of CP Ti. However, nohysteresis loops are found in the reverse scanning curves of Cu-Cr alloy. A complex oxide film ofCo_3O_4, Co_2._3, and Cr_2._3 formed on the surface provides Co-Cr alloy with a stableelectrochemistry property. The corrosion rates of the crevice samples increase with the pH value ofmedium decreasing. The electron probe microanalyzer (EPMA) analysis indicates that Ti in CP Ti andCo, Cr in Co-Cr alloy dissolve in crevice area due to the Sealed-Cell effect.

关键词： ringer's solution biomedical material electrochemical behaviors

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ICALCIUM IS INVOLVED IN THE ABSCISICACID-INDUCEDCHILLING RESISTANCE,ASCORBATE PEROXIDASE AND SUPEROXIDE DISMUTASE IN STYLOSANTHES GUIANENSIS

ICALCIUM IS INVOLVED IN THE ABSCISICACID-INDUCEDCHILLING RES...

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中国草学会青年工作委员会学术研讨会

作者： ZHOU Biyan GUO Zhenfei (Biotechnology Laboratory for Turfgrass and Forages,college of Life Science,{2. china Agricultural university,guangzhou 510642.china)

The objective of this work was to test whether Ca

关键词： ABA calcium chilling resistance Stylosanthes guianensis

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Partial Inverse Grain Size Dependence of Strength in High Mn Steels Microalloyed With Nb

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Journal of Iron and Steel Research International 2012年第9期19卷 68-72页

作者： DING Hua 1 , 2., LI Hua-ying 1 , DING Hao 1 , QIU Chun-lin 2., TANG Zheng-you 1 ( 1.School of Materials and Metallurgy , Northeastern university , Shenyang 110819 , Liaoning , china 2.State Key Lab of Rolling and {2.mation , Northeastern university , Shenyang 110819 , Liaoning , china ) School of Materials and Metallurgy Northeastern University Shenyang Liaoning China State Key Lab of Rolling and automation Northeastern University Shenyang Liaoning China

Two steels without and with Nb addition were chosen to investigate the effects of Nb on the microstructures and the mechanical properties of Fe-Mn-Al-Si *** results revealed that Nb refined the grains markedly and both TRIP and TWIP effects occurred during deformation *** Nb containing steel possesses higher yield strength and much lower tensile strength , the latter being explained by the suppression of TRIP effect due to the increase of stacking fault *** indicates grain refining is secondary for strengthening of steels when TRIP or TWIP effect exists during the deformation of low carbon and high Mn steels.

关键词： grain size strength high Mn steel Nb

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Mechanism and control of ground residual deformation over longwall goaf

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中国有色金属学会会刊：英文版 2005年第S1期15卷 76-79页

作者： GUO Guang-li~1, WEI Kuang-ling~2. MU Bin-shan~3, Gao Jing-xiang~1, HE Guo-qing~1 (1. china university of Mining and {2., Xuzhou 2.1008, china 2. Chongqing university, Chongqing 400044, china 3. Qiwu Coal Mine, Jining 2.7606, china)

The deformation of rupture rock mass in goaf is the main reason for ground terrene residual deformation. Based on field measurement and similar material simulation, the rupture strata structure and its residual deformation characteristics in the longwall goaf and its overburden are pointed out. On the basis of these achievements, the authors propose the mechanism of strengthening rupture rock mass ground and the control measures of deformation resistant structure. Using the case of main coal building in Xinzhuangzi Coal Processing Plant, this paper introduces the influence of strengthening rupture rock mass and deformation resistant structure.

关键词： abandoned goaf residual deformation rupture rockmass deformation mechanism deformation control

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