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Chinese Science Bulletin 2002年第13期47卷 1113-1118页

作者： ZHANG Xiaohui, LI Tiesheng & PU ZhipingResearch Center of mineral resources Exploration, institute of geology and Geophysics, Chinese Academy of Sciences, beijing 100101, china Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51 Research Center of mineral resources Exploration Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Two ductile shear zones trending EW and NNE respectively not only controlled the tectonic framework of the northern North china, but also constrained the geody-namic background for gold mineralization in this region. Field observations and microstructural analyses reveal that the EW trending ductile shear zones are mainly contributed to dextral compressional deformation resulting from top-to-the-southeast oblique thrust shearing, whereas the NNE trending ones are genetically related to sinistral strike-slip and extensional faulting. One sample from the former yielded an 40Ar-39Ar plateau age of (219±4) Ma (Bi) and two samples from the latter gave 40Ar-39Ar plateau ages of (116± 2) Ma (Bi) and (127±3) Ma (Bi). These ages provide constraints on the top-to-the-southeast oblique thrusting event occurring in Late Triassic and the sinistral extensional and strike-slip faulting event which occurred in Early Cretaceous.

关键词： 40Ar-39Ar age biotite ductile shear zone West Liaoning Region.

^(40)Ar-^(39)Ar ages of the Louzidian-Dachengzi ductile shear zone near Chifeng,Inner Mongolia and their tectonic significance

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Chinese Science Bulletin 2002年第15期47卷 1292-1297页

作者： ZHANG Xiaohui, LI Tiesheng, PU Zhiping & WANG HuiResearch Center for mineral resources Exploration, institute of geology and Geophysics, Chinese Academy of Sciences, beijing 100101, china Guangzhou institute of Geochemistry, Chinese Academy of Sciences, G Research Center for mineral resources Exploration Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

The Louzidian normal fault occurs as the eastern detachment fault of the Kalaqin metamorphic core complex. Field observations and microstructural analyses reveal that the Louzidian-Dachengzi ductile shear zone developed in its lower-plate was genetically related to sinistral strike-slips and extensional faulting. Two samples from this ductile shear zone yield 40Ar-39Ar plateau ages of 133 Ma (Bi) and 126 Ma (Kp), which are concordant with their isochron ages. The plateau age of 133 Ma (Bi) records the formation age of the ductile shear zone. The inconsistent relationship between the earlier strike-slip ductile shear zone and the later normal fault makes the Kalaqin Quasi-metamorphic core complex distinctive from Cordil-leran nietamorphic core complex. These ages provide important geochronological data for putting constraints on the formation age and genesis of such ductile shear zones.

关键词： 40Ar-39Ar age Sinistral strike-slip Louzidian-Dachengzi ductile shear zone Metamorphic core complex.

Si-and alkali-rich melt inclusions in minerals of mantle peridotites from eastern china:Implication for lithospheric evolution

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Science china Earth Sciences 2006年第1期49卷 43-49页

作者： FAN Qicheng1, SUI Jianli2, XU Ping2, LI Ni1, SUN Qian1 & WANG Tuanhua1 1. institute of geology, china Seismological Bureau, beijing 100029, china 2. institute of geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china institute of geology China Seismological Bureau Beijing China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

minerals of spinel- and garnet-facies mantle xenoliths entrained in Cenozoicbasalts from eastern china (North china, Northeastern china and Southeastern china coastal area)contains lots of melt inclusions. Studies on these melt inclusions show that the glass inclusionsare rich in SiO_2 (60%—68%) and alkalis (K_2O+Na_2O = 5%—11%, especially for K_2O) as well asvolatiles such as H_2O and CO_2 (2%—7%), which belong to dacites and andesites of the high-K calcicalkali series rocks with few shoshonites. High Al and Ca diopside in melt inclusion is the productof melt crystallization at high temperature and pressure, rather than the product ofdevitrification. Results show that these K-rich (in general K_2O > 3%) intermediate-acidic silicatemelt inclusions have characteristics of continent without a genetical link to host basalts and theirphenocrystic minerals. Thus, these trapped melt inclusions represent melts of Mesozoic lithosphericmantle-crust interaction and imply that the continental lithospheric mantle beneath eastern chinahad undergone fragmentation and recreation processes during the Mesozoic and Cenozoic periods. Thisresult undoubtly provides important implication for the evolution of sub-continental lithospherebeneath eastern china. We propose that these Si- and alkalis-rich melts should be responsible forthe mantle chemical heterogeneity underneath eastern china.

关键词： Si- and alkali-rich melt inclusion, mantle peridotite, lithospheric evolution, eastern china.

Paleomagnetic study on orogenic belt:An example from Early Cretaceous volcanic rocks,Inner Mongolia,china

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Science china Earth Sciences 2004年第12期47卷 1127-1133页

作者： REN Shoumai 1,2 ,ZHU Rixiang 1 ,HUANG Baochun 1 ,ZHANG Fuqin 1 & WANG Hongqiang 1 1.institute of geology and Geophysics,Chinese Academy of Sciences,beijing 100029,china 2.Strategic Research Center for Oil and Natural Gas,The Ministry of Land and resources of china,beijing 100034,china Strategic Research Center for Oil and Natural Gas The Ministry of Land and Resources of China Beijing China Chinese Academy of Sciences Institute of Geology and Geophysics Beijing China

We report paleomagnetic results for Early Cretaceous lava flows collected from the Suhongtu area of Inner Mongolia, the middle part of the Tianshan-Mongolia Fold Belt (TMFB). Rock-magnetic experiments for different lava flows indicate that the main magnetic mineral is pseudo-single-domain (PSD) magnetite. The characteristic high-temperature remanence com- ponent is isolated by thermal demagnetization temperature steps between 300°C and 585"C, which yields a mean direction of D = 23.6°, I=56.0° with α 95 = 2.3°. We interpret this high-temperature remanence component as primary magnetization based mainly upon the petrographic analysis, which shows that the shape of magnetite crystal is relatively rounded square or polygon without internal reflection and deuterogenous phenomenon. The correspond- ing pole of the high-temperature remanence component is at 71.1°N, 200.5°E with A 95 = 2.7°. This Early Cretaceous pole is in good agreement with those for Siberia, North china, and Inner Mongolia, suggesting that these continental blocks had already sutured together in the Early Cretaceous, which would further provide constraints on better understanding of the formation and evolution of the TMFB.

关键词： orogenic belt, paleomagnetism, Suhongtu of Inner Mongolia, Eurasia.

The relative generalized Hamming weight and the semilinear equivalence of codes

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Science china(Information Sciences) 2011年第4期54卷 787-794页

作者： LIU ZiHui 1 & WANG Jie 2 1 Department of Mathematics,beijing institute of Technology,beijing 100081,china 2 School of Mathematical Sciences,beijing University,beijing 100871,china Department of Mathematics Beijing Institute of Technology Beijing China School of Mathematical Sciences Beijing University Beijing China

Certain equivalent conditions are given for the semilinear equivalence of linear codes by using the relative generalized Hamming weight and the value function.

关键词： value function semilinear equivalence support weight relative generalized Hamming weight

Microstructure and Frictional Behavior of Fe-based Amorphous Metallic Coatings Prepared by Atmospheric Plasma Spraying

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稀有金属材料与工程 2011年第S3期40卷 160-165页

作者： Zhou Zheng1,2, Wang Lu2, He Dingyong1, Liu Yanbo2, Zhang Guanzhen1 1 beijing University of Technology, beijing 100124, china 2.beijing institute of Technology, beijing 100081, china beijing Univ Technol Beijing 100124 Peoples R China beijing Inst Technol Beijing 100081 Peoples R China

Amorphous metallic coatings with a composition of Fe48Cr15Mo14C15B6Y2 were prepared by means of atmospheric plasma spraying (APS) process under different conditions. The microstructure and frictional behavior were characterized simultaneously in this article. The results show that the as-deposited coatings consist of amorphous matrix and some precipitated nanocrystals, while the amorphous fraction and particle deformation as well as crystallization mechanism are significantly sensitive to the spraying parameters. The amorphous coatings express high microhardness and excellent wear resistance under dry frictional wear condition, which attributes to the inherent characteristic of amorphous phase and the dispersion strengthening of precipitated nanocrystals. The dominant wear mechanism of the amorphous coatings is fatigue wear accompanying with oxidative wear. In addition, the microhardness and wear resistance of the amorphous coatings were improved by optimizing spraying parameters, owing to the effect of both structural character and proper proportional of amorphous and nanocrystals fraction.

关键词： Fe-based amorphous coating APS microstructure friction

Corrosion and electrochemical behavior of as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys in 5%NaCl aqueous solution

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Progress in Natural Science:Materials International 2011年第4期21卷 314-321页

作者： Xin ZHANG~(1,2,3),Kui ZHANG~1,Xing-gang LI~1,Cong WANG~4,Hong-wei LI~(2,3),Chang-shun WANG~(2,3),Xia DENG~1 1.State Key Laboratory for Fabrication and Processing of Nonferrous Metals, beijing General Research institute for Nonferrous Metals,beijing 100088,china 2.beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts,beijing 100072,china 3.institute of Technology,beijing North Vehicle Group Corporation,beijing 100072,china 4.Fengtai Military Representative Office,beijing Military Representative Office,PLA,beijing 100072,china State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts Beijing 100072 China institute of Technology Beijing North Vehicle Group Corporation Beijing 100072 China Fengtai Military Representative Office Beijing Military Representative Office PLA Beijing 100072 China

The corrosion mechanism of the as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloy immersed in 5%NaCl aqueous solution was investigated by electrochemical test and *** electrochemical results indicate that the corrosion resistance of Mg-5Y-7Gd-1Nd-0.5Zr alloy in 5%NaCl aqueous solution gradually deteriorates with immersion time increasing from 2 h,24 h,60 h,to 108 h,which is consistent with the SEM observation of corrosion *** Cl-anion leads to the initiation and development of the corrosion pits,and Mg-5Y-7Gd-1Nd-0.5Zr alloy exhibits filiform type of attack under significant anodic control of magnesium solution *** corrosion potential becomes noble with increasing immersion time.

关键词： magnesium alloys Mg-5Y-7Gd-1Nd-0.5Zr corrosion electrochemical behavior

Rare Earth Element Behaviour in theWunugetushan Copper - Molybdenum Deposit,Inner Mongolia, and Its Implications

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Acta Geologica Sinica(English Edition) 1994年第2期68卷 153-167页

作者： Qin Kezhang and Wang Zhitianbeijing institute of geology for M ineral resources, CNNC, beijing beijing institute of geology for mineral resources CNNC Beijing

Considering porphyry and wall rocks as a whole system, the behaviour of rare earth elements (REE) in hydrothermal alteration and mineralization of the exceedingly large Wunugetushan porphyry Cu-Mo deposit of Inner Mongolia has been studied. It has been found for the first time that there exists complementary REE variation in hydrothermal alteration between porphyry and wall rocks, and Eu depletion has certain significance in indicating mineralization. Based on an analysis of the variation in REE contents of relevant minerals during the hydrothermal alteration, the ore-forming fluids are inferred to be depleted in ∑REE, comparatively enriched in ∑Y and strongly depleted in Eu. In the intermediate-strong alteration zones, porphyry and wall rock took part in hydrothermal metasomatism and alteration almost in equal ratio mass. Furthermore, studies of REE and hydrogen and oxygen isotopes and fluid inclusions confirm the existence of hydrothermal convection and the possibility of supplying part of ore materials by the wall rock and indicate that the application of REE geochemistry in mineral prospecting is promising.

关键词： REE complementary nature Eu depletion hydrothermal convection Wunugetushan Cu-Mo deposit Inner Mongolia

Hydraulic characteristics of converse curvature section and aerator in high-head and large discharge spillway tunnel

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Science china(Technological Sciences) 2011年第S1期54卷 33-39页

作者： LIU ZhiPing 1,2,ZHANG Dong 2,ZHANG HongWei 2 &WU YiHong 1,2 1 State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,beijing 100038,china 2 china institute of Water resources and Hydropower Research,beijing 100038,china State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin Beijing China china institute of Water resources and Hydropower Research Beijing China

The hydraulic characteristics and cavitation erosion near the converse curvature section in the high-head and large discharge spillway tunnel have been important issues of concern to the hydropower *** this paper,the evolutions of hydraulic elements such as pressure,flow velocity,wall shear stress,*** the converse curvature section are analyzed and the impacts of bottom aerator on hydraulic characteristics are discussed,with the commercial software FLUENT6.3 as a platform and combining the k-model and VOF *** flow pattern in the converse curvature section of spillway tunnel is given by the three-dimensional numerical *** indicates that the pressure changes rapidly with great pressure gradient from the beginning to the end of the *** also shows that the shear stress on side wall just downstream the end of the converse curvature curve is still increasing;the aeration cavity formed downstream the bottom aerator may cause the side wall pressure decreased to worsen the cavitation characteristics near the side *** means of the physical model experiment,the three-dimensional aerator composed of side wall baffling aerator and bottom aerator is studied,the baffling aerator suitable for the water flow conditions with water depth of 6.0 to 8.0 m and flow velocity of 35 to 50 m/s is proposed.

关键词： spillway tunnel baffling aerator converse curvature section hydraulic characteristics

Zijinshan-Bitian Cu-Au-Mo orefield, SW Fujian——An example of gold-rich PCS zoning

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Chinese Science Bulletin 1999年第S2期44卷 134-135页

作者： QI Jianzhong~1, LI Zhaonai~2, ZHANG Dequan~3, FANG Xiheng~4 and XIAO Huiliang~1 1. Nanjing institute of geology and mineral resources, Chinese Academy of Geological Sciences, Nanjing 210016, china 2. institute of geology, Chinese Academy of Geological Sciences, beijing 100037, china 3. institute of mineral Deposits, Chinese Academy of Geological Sciences, beijing 100037, china 4. institute of geology, Ministry of Nuclear Industry, beijing 100013, china Nanjing institute of geology and mineral resources Chinese Academy of Geological Sciences Nanjing 210016 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China institute of mineral Deposits Chinese Academy of Geological Sciences Beijing 100037 China institute of geology Ministry of Nuclear Industry Beijing 100013 China

THE Zijinshan-Bitian Cu-Au-Mo orefield is spread to north of the Shanghang County, SW *** geological structure it is located at the plunging end of NE-trending Xuanhe anticlinorium, in the NE rim ofthe NW trending Shanghang volcano-sedimentary basin. Orefield basement is composed of the Archean-Middle Proterozoic low-grade metamorphic rock formations, containing marine basic metavolcanic sequenses. Lower Cretaceous subaerial volcanic rocks of andesite-trachy andesite-rhyolite composition fill inthe volcano-sedimentary basin. Pre-mineralization granitic batholith dated 145Ma（Rb-Sr）and 157Ma（U-Pb） occupies the axial part of the plunging anticlinorium, which was regarded as crust-remelting typegranitoids. mineralization-affiliated subvolcanic dacite porphyrite, co-volcanic granodiorite and quartzdiorite porphyrite （102.2 Ma（Rb-Sr）, Sr1 = 0.708 9） belong to syntactic type in genesis and

关键词： gold-rich porphyre copper system zoning Fujian Zijinshan.