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Discovery of Cu-Zn,Cu-Sn intermetallic minerals and its significance for genesis of the Mianning-Dechang REE Metallogenic Belt,Sichuan Province,china

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science china Earth sciences 2006年第6期49卷 597-603页

作者： xie yuling1, hou zengqian2. xu jiuhua1, YUAN Zhongxin2. BAI Ge2.& LI Xiaoyu3.1. Civil and Environmental Engineering School, University of {2. and technology beijing, beijing 100083. china 2. Institute of Geology, Chinese Academy of Geological {2.s, beijing 10003., china 3. The 109th Geological Team, Sichuan Bureau of Mineral Exploration, Chengdu 610100, china 1. Civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China 2. Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China 3. The 109th Geological Team Sichuan Bureau of Mineral Exploration Chengdu 610100 China

Mianning-Dechang Himalayan REE Metallogenetic Belt in Sichuan Province lies along the western margin of the Yangtze Craton. We have conducted detailed mineralogical studies on ore minerals collected from Maoniuping and Dalucao, the two largest deposits in the belt. With optical microscope, SEM/EDS, and EPMA, three rare intermetallic minerals, i.e., zinccopperite (Cu2.n), Sn- bearing native copper, and Cu-bearing jupiter were found to occur in the main ore along with barite, fluorite, apatite, sulfide and bastnaesite. Since the conditions under which zinccopperite and Sn- bearing native copper formed are quite unique, finding of these minerals, for the first time in domestic REE deposits, has significant implications for the genesis of the ore deposits in which they occur. In comparison with Cu-Zn intermetallic minerals in other occurrences, we propose that the formation of this REE metallogenetic belt is associated with fast upwelling of the Himalayan magma from deep source.

关键词： Mianning-Dechang REE metallogenetic belt, Cu-bearing intermetallic minerals, EPMA, genesis significance, deep source magmatic activity.

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碳酸岩研究进展

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岩石学报 2024年第3期40卷 1003-1022页

作者：尹淑苹谢玉玲侯增谦曲云伟北京科技大学土木与资源工程学院北京100083 中国地质科学院地质研究所北京100037

碳酸岩(carbonatite)一词自首次被提出至今已有一百多年的历史,它是一种神秘而颇具争议的岩石类型。碳酸岩富含碳酸盐矿物,通常与基性、超基性或碱性硅酸盐岩伴生形成碳酸岩-硅酸盐岩杂岩体,具有独特的化学成分和矿物学特征并具有承载... 详细信息

碳酸岩(carbonatite)一词自首次被提出至今已有一百多年的历史,它是一种神秘而颇具争议的岩石类型。碳酸岩富含碳酸盐矿物,通常与基性、超基性或碱性硅酸盐岩伴生形成碳酸岩-硅酸盐岩杂岩体,具有独特的化学成分和矿物学特征并具有承载重要经济矿床的能力。在过去的几十年里,碳酸岩的研究在岩石成因及岩浆起源、地球化学与地质年代学、高温高压实验、与碳酸岩相关的经济矿产、碳酸岩型稀土矿床中稀土元素的富集分异及成矿机理等领域取得了巨大进步。本文从碳酸岩的定义与分类、成岩背景与时空分布、岩石学特征及矿物组成、岩浆起源及演化过程以及与碳酸岩相关的矿产资源等方面对碳酸岩的研究进展进行了综述与评论,提出从成因角度探索碳酸岩分类方案的必要性,总结和梳理了我国目前发现的碳酸岩的产地和分布特征,并认为碳酸岩岩浆与硅酸盐岩浆演化具有差异性,应重视对碳酸岩岩浆演化过程中熔体-流体过渡阶段的研究。最后从文献计量学角度利用大数据和可视化手段对来自Scopus数据库的近十年以“carbonatite”为检索词的近千篇文献进行了可视化分析,总结归纳了碳酸岩现阶段的研究热点,并对未来碳酸岩的研究趋势进行了展望。

关键词：碳酸岩定义与分类时空分布岩石矿物学特征岩浆经济矿产

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Hybrid microsystem with functionalized silicon substrate and PDMS sample operating microchannel: A reconfigurable microfluidics scheme

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science china(Technological sciences) 2010年第8期53卷 2272-2277页

作者： LEI YinHua 1 ,xie Fei 1 ,WANG Wei 1,2.,WANG HaiBin 3.&LI ZhiHong 1,2.1 Institute of Microelectronics,Peking University,{3. 100871,{2. 2.ational Key Laboratory of {2. and technology on Micro/Nano Fabrication,{3. 100871,{2. 3.No.3.2.Hospital,{3. 10003.,{2. 1. Institute of Microelectronics Peking University Beijing 100871 China2. National Key Laboratory of Science and Technology on Micro/Nano Fabrication Beijing 100871 China3. No. 302 Hospital Beijing 100039 China

A hybrid microsystem with separately functioned temperature controlling substrate and sample operating fluidic microchannel was developed to demonstrate a reconfigurable microfluidics *** temperature controlling substrate integrated a micro heater and a temperature sensor by using traditional silicon-based micromechanical system(MEMS)technique,which guaranteed high performance and robust reliability for repeatable *** sample operating fluidic microchannel was prepared by poly-(dimethylsiloxane) (PDMS)based soft lithography technique,which made it cheap enough for disposable *** PDMS microchannel chip was attached to the temperature controlling substrate for reconfigurable thermal applications.A thin PDMS film was used to seal the microchannel and bridge the functionalized substrate and the sample inside the channel,which facilitated heat transferring and prevented sample contaminating the temperature controlling *** by a one dimensional thermal resistance model,the thin PDMS film was important for the present reconfiguration *** performance of this hybrid microsystem was examined,and the experimental results demonstrated that the chip system could work stably over hours with temperature variation less than *** PDMS microchannel chips were tested on one heating substrate sequentially with a maximum intra-chip temperature difference of *** extracted from serum of a chronic hepatitis B virus(HBV)patient was amplified by this hybrid microsystem and the gel electrophoresis result indicated that the present reconfigurable microfluidic scheme worked successfully.

关键词： reconfigurable microfluidics hybrid microdevice thin PDMS film

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Prediction method for October 2.03.solar storm

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science china(Technological sciences) 2006年第5期49卷 629-640页

作者： xie Yanqiong1, 2. 3. WEI Fengsi1, FENG xueshang1 & ZHONG Dingkun1, 2.1. State Key Laboratory of Space Weather, Center for Space {2. and Applied Research, Chinese Academy of {2.s, {2. 100080, china 2. Graduate School, Chinese Academy of {2.s, {2. 10003., china 3. Institute of Meteorology, PLA University of {2. and {13., Nanjing 2.1101, china State Key Laboratory of Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100039 China Institute of Meteorology PLA University of Science technology Nanjing 211101 China

Aiming at two intense shock events on October 2. and 2., 2.03. this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

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Photogeneration of the free radicals and singlet oxygen by chrysophanol from rheum

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science china Chemistry 2004年第5期47卷 381-387页

作者： RAO Jing1,2. xie Jie1, ZHAO Jingquan1 & ZHU Teng2.1. Key Laboratory of Photochemistry, Center for Molecular {3., Institute of Chemistry, The Chinese Academy of {3.s, {2. 100080, china 2. University of {3. and technology {2., {2. 10083. china 1. Key Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry The Chinese Academy of Sciences 100080 Beijing China 2. University of science and technology {2. 10083 Beijing China

In the current work, chryosphanol (MHAQ) was isolated and purified from rheum, and the photosensitization activities were studied. In nitrogen-saturated DMSO solution, irradia- tion of chryosphanol (MHAQ) with visible light (>43. nm) produced the semiquinone radical anions (MHAQ??), which was intensified significantly by an electron donor NADH, suggesting electron transfer between the excited and ground state photosensitizer molecules. In an air-saturated DMSO solution, superoxide radical anions (O2.), trapped by DMPO, were detected. ?? It was proved that O2.was not originated from the singlet oxygen (1O2. but dependent on DMPO, ?? chrysophanol, oxygen and the irradiation time. The singlet oxygen and OH could also be pro- ? duced by the photosensitization of the photosensitizer. These suggest that chrysophanol pos- sesses the photosensitization activity via Type I mechanism and Type II mechanism. To evaluate the photosensitization activities of MHAQ, emodin and mixed anthraquinone derivatives ex- tracted from rheum, the relative productivities of O2.were estimated to be 1.8, 1.1 and 1.0 re- ?? spectively and the quantum yields for singlet oxygen to be 0.3., 0.53.and 0.14 respectively. Therefore, these low-cost pigments may be potentially used as phototherapeutic medicine for some kind of vascular diseases or photo-activated pesticides.

关键词： chrysophanol, ESR, semiquinone radical anions, superoxide radical anions, hydroxyl radical, singlet oxygen.

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Self-healing routing: failure,modeling and analysis

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science china(Information sciences) 2011年第3期54卷 609-622页

作者： xu MingWei 1,2., LI Qi 1,2., YANG Yuan 1,2., hou MeiJia 1,2.& PAN LingTao 1,2.1 Department of Computer {2., Tsinghua University, beijing 100084, {2. 2.Tsinghua National Laboratory for Information {2. and technology (TNList), beijing 100084, {2. 1. Department of Computer science Tsinghua University Beijing 100084 China2. Tsinghua National Laboratory for Information Science and Technology (TNList) Beijing 100084 China

Network failures occur frequently, and self-healing ability of existing routing protocols cannot guarantee fast route convergence under these failures without impacting packet forwarding. During routing convergence, network routes may be incorrect and even routing black holes and loops occur, which will result in extensive packet loss and thus influence network performance. To solve this problem, several improved routing solutions have been proposed. In this paper, we propose the concept and model of self-healing routing and analyze the key problems in current intra-domain and inter-domain self-healing routing protocols after briefly reviewing the characteristics of network failures. We classify the different self-healing solutions into two categories based on their design principles: routing restoration and routing protection, and systematically analyze these different typical solutions. Finally, we discuss several key issues in self-healing routing and propose a hybrid protection and restoration based routing scheme.

关键词： failure intra-domain routing inter-domain routing self-healing routing

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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. Z{3. HongWei1,2.PENG SuPing1 1 State Key Laboratory of Coal Resources and Safe Mining, {2. University of Mining and technology,{2. 2.Institute of Rock Mechanics and Fractals, {2. University of Mining and technology,{2. 3.Sichuan University, Chengdu 610065, {2. 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

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Wear-resistant Ag-MAX phase 3. interpenetrating-phase composites:Processing,structure,and properties

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Nano Research 2024年第2期17卷 806-819页

作者： Yu Guo Xi xie zengqian Liu Longchao Zhuo Jian Zhang Shaogang Wang Qiqiang Duan Qing Jia Dake {2. Weihai {2.e Deli Duan Filippo Berto Zhefeng Zhang Rui Yang Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials science and Engineering Xi’an University of TechnologyXi’an 710048China Electrobiomaterials Institute Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China Shenyang National Laboratory for Materials science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Chemical Engineering Materials and EnvironmentSapienza University of RomeRoma 00185Italy

Electrical contact materials are generally Ag-or Cu-based composites and play a critical role in ensuring the reliability and efficiency of electrical equipments and electronic *** MAX(M is an early transition metal,A is an element from III or IV main groups,and X is carbon or/and nitrogen)phase ceramics display a unique combination of properties and may serve as an ideal reinforcement phase for electrical contact *** biological materials evolved in nature generally exhibit three-dimensional(3.)interpenetrating-phase architectures,which may offer useful inspiration for the architectural design of electrical contact ***,a series of bi-continuous Ag-Ti_(3.SiC_(2. MAX phase composites with high ceramic contents exceeding 50 vol.%and having micron-and ultrafine-scaled 3. interpenetrating-phase architectures,wherein both constituents were continuous and mutually interspersed,were exploited by pressureless infiltration of Ag melt into partially sintered Ti_(3.SiC_(2. *** mechanical and electrical properties as well as the friction and wear performance of the composites were investigated and revealed to be closely dependent on the ceramic contents and characteristic structural *** composites exhibited a good combination of properties with high hardness over 2.3.GPa,high fle{3.ral strength exceeding 53. MPa,decent fracture toughness over 10 MPa·m^(1/2.,and good wear resistance with low wear rate at an order of 10^(-5)mm^(3./(N·m),which were much superior compared to the counterparts made by powder metallurgy *** particular,the hardness,electrical conductivity,strength,and fracture toughness of the composites demonstrated a simultaneous improvement as the structure was refined from micron-to ultrafine-scales at equivalent ceramic *** good combination of properties along with the facile processing route makes the Ag-Ti_(3.SiC_(2.3. interpenetrating-phase composites appealing for electrical contact applicatio

关键词： three-dimensional(3.)interpenetrating-phase architecture Ag-MAX(M=early transition metal A=element from III or IV main groups and X=carbon or/and nitrogen)phase composites melt infiltration electrical contact materials mechanical

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Effects of Cobalt on the Sintering Behavior of Mechanically Activated Tungsten Powder

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Rare Metals 2001年第3期20卷 183-186页

作者： Chengchang Jia, Xiaoyang Liu, Xiuhu Guan, xuekuan Su, Jun Zhao, Zizhang xie 1) Materials {2. and Engineering School, University of {2. and {2. beijing, beijing 100083. china 2. beijing Research Institute of Powder Metallutrgy, beijing 10005 Univ Sci & Technol beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China beijing Res Inst Powder Met Beijing 100053 Peoples R China beijing Polytech Univ Beijing 100022 Peoples R China

Tungsten alloys were prepared with mechanically activated powder added microelement cobalt in order to improve the process and properties of alloys. Properties of alloys such as density, hardness and bending strength were measured. The results show that through mechanical activation, cobalt can accelerate the sintering process of these alloys By the combination of mechanical activation and adding microelement cobalt, tungsten alloys with higher density and better properties can be obtained.

关键词： powder metallurgy tungsten alloys cobalt mechanical activation sintering behavior

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Energy analysis for damage and catastrophic failure of rocks

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science china(Technological sciences) 2011年第S1期54卷 199-209页

作者： xie HePing 1,2.LI LiYun 2.1,JU Yang 2.PENG RuiDong 2.& YANG YongMing 2.1 Sichuan University,Chengdu 610065,china 2.State Key Laboratory of Coal Resources and Safe Mining,{2. Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete,china University of Mining and technology,{2. 100083.china 1. Sichuan University Chengdu 610065 China 2. State Key Laboratory of Coal Resources and Safe Mining Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete China University of Mining and Technology Beijing 100083 China

The development history and current state of studies on the characteristics and mechanisms of deformation and failure of rock materials were briefly reviewed from the viewpoint of *** main scope and the achievable objectives of the energy-based research system were *** was validated by experiments that the damage process of rocks can be well described by the rock damage evolution equation established based on energy *** was found from the uniaxial compression and biaxial compression tests that only a small proportion of the total input energy in hard rocks is dissipated before peak load and a large proportion in soft rocks is dissipated before peak *** both hard and soft rocks,the energy dissipated after peak load accounts for a greater *** energy would be required for rock failure under equal biaxial compression than under unequal biaxial *** total absorbed energy is different for rock failure under high-rate loading and low-rate *** fragmented failure pattern usually corresponds to higher energy *** mesoscopic analysis on the damage and failure of bedded salt rocks showed that the energy dissipation is prominent and the total absorbed energy for rock failure is low when cracks propagate in the weak mud interlayer while it is contrary when cracks propagate in the salt *** energy accumulation,transfer,dissipation and release during the failure process of tunnel with impending failure under disturbance were analyzed theoretically based on the elastoplastic mechanics ***,the spatial distribution of energy dissipation and energy release of fractured rocks under unloading was simulated *** was demonstrated that energy is likely to be released from the weakest surface under compression,which triggers the global failure of rocks.

关键词： rock deformation failure energy accumulation energy dissipation energy release

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