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Thermal history of the Sichuan Basin,SW China:Evidence from deep boreholes

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Science China Earth Sciences 2016年第1期59卷 70-82页

作者： ZHU Chuan Qing HU ShengBiao QIU NanSheng rao Song YUAN YuSong State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China College of Geosciences China University of PetroleumBeijing 102249China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China College of Geosciences Yangtze UniversityJinzhou 434023China Exploration and Productton Research Institute SINOPECBeijing 100083China

The Sichuan Basin is a superimposition basin composed of terrestrial and marine sediments that is well known for its abundant petroleum resources. Thermal history reconstruction using paleogeothermal indicators, including vitrinite reflectahoe and thermochronological data, shows that different structural subsections of the Sichuan Basin have experienced various paleogeothermal episodes since the Paleozoic. The lower structural subsection comprising the Lower Paleozoic to middle Permian （Pz-P2） successions experienced a high paleogeothermal gradient （23.0-42.6℃/km） at the end of the middle Permian （P2）, whereas the upper structural subsection comprising Late Permian to mesozoic strata underwent a relatively lower paleogeothermal gradient （13.2-26.9℃/km） at the beginning of the denudation （Late Cretaceous or Paleocene in the different regions）. During the denudation period, the Sichuan Basin experienced a successive cooling episode. The high paleogeothermal gradient resulted from an intensive thermal event correlated to the Emeishan mantle plume. The heat flow value reached 124.0 mW/m2 in the southwestern basin near the center of the Emeishan large igneous province. The low geothermal gradient episode with heat flow ranging from 31.2 to 70.0 mW/m2 may be related to the foreland basin evolution. The cooling event is a result of the continuous uplift and denudation of the basin.

关键词： Paleotemperature gradient Paleo-heat flow Vitrinite reflectance Emeishan mantle plume Sichuan Basin

Effect of wheel speed on phase formation and magnetic properties of (Nd_(0.4)La_(0.6))-Fe-B melt-spun ribbons

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Journal of Rare Earths 2018年第11期36卷 1179-1183页

作者： Liang Wang Jiang Wang maohua Rong Guanghui rao Huaiying Zhou School of material Science and Engineering & Guangxi Key Laboratory of Information materials Guilin University of Electronic Technology Guilin 541004China

The effect of wheel speed on phase formation and magnetic properties of （Ndo.4La0.6）lsFeTzsBzs and （Ndo.4La0.6）13.4Fe79.9B6.7 ribbons prepared by melt-spinning method was investigated experimentally. Based on X-ray diffraction results, all melt-spun ribbons consist of the main phase with the tetragonal 2：14：1 type structure and the minor α-Fe phase. magnetic measurements show the maximum magnetic energy product （（BH）max） and the remanence （mr） increases firstly and then decreases with the increase of wheel speed, while the coercivity （Hci） increases, resulting from the variation of the average volume fraction of the ^-Fe phase and the average grain size in the melt-spun ribbons. Using Henkel plots, the interaction between the 2：14：1 phase and the ^-Fe phase in the melt-spun ribbons was analyzed and the intergranular exchange coupling is manifested. Optimal magnetic properties of Hci - 7.27 kOe, mr - 90.94 emu/g and （BH）max -- 12.10 mGOe are achieved in the （Ndo.4La0.6）lsFeTzsBT.s ribbon with the wheel speed of 26 m/s. It indicates that magnetic properties of Nd-Fe-B melt-spun ribbons with highly abundant rare earth element La can be improved by optimizing alloy composition and preparation process.

关键词： Nd-La-Fe-B ribbons Phase formation melt-spinning magnetic properties Rare earths

Effect of Different Rare-Earth on microstructure and Properties of α-Sialon Ceramics

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Journal of materials Science & Technology 2008年第6期24卷 878-882页

作者： Chunfeng LIU Feng YE Yu ZHOU Yongliang WANG Jiancun rao Institute for Advanced Ceramics Harbin Institute of Technology Harbin 150001 China

Densified Yb-, Y-, Dy-, Sin- and Nd-α-Sialon ceramics were prepared by two-step hot sintering. The variation of microstructure and properties with different rare-earth was investigated. The ceramics doped with smaller cations （Yb3＋, y3＋ and Dy3＋） are fully composed of α-Sialon, while in the larger cations （Sm3＋ and Nd3＋） doped ceramics also exist a few intergranular phase mt （Re2Si3-xAlxO3＋xN4-x） in triple-point pockets. With increasing the radius of the rare-earth cations, the elongated α-Sialon grains form instead of the equiaxed grains in Yb-α-Sialon, and the aspect ratio of grains increases. All the ceramics possess high hardness, and the value of 21 GPa is achieved for Yb- and Y-α-Sialon. With increasing the ionic size of rare-earth, the hardness decreases slightly but the toughness tends to increase. Nd-α-Sialon possesses the highest toughness with the value of 5.4 mPa·m^1/2.

关键词： α-Sialon Rare-earth microstructure mechanical properties

Thermal and maturation history for Carboniferous source rocks in the Junggar Basin, Northwest China: implications for hydrocarbon exploration

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Petroleum Science 2020年第1期17卷 36-50页

作者： Di Hu Song rao Zhu-Ting Wang Sheng-Biao Hu State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China Key Laboratory of Exploration Technologies for Oil and Gas Resources Ministry of EducationYangtze UniversityWuhan 430100HubeiChina

The reconstruction of thermal history is an important component of basin evolution and hydrocarbon *** on vitrinite reflectance data,we integrate the paleo-temperature gradient and paleo-heat flow methods to reconstruct the thermal history of Junggar *** with present thermal state,the Junggar Basin experienced much a higher heat flow of ca.80–120 mW/m2 during the *** feature can be attributed to large-scale volcanic events and related thermal *** hydrocarbon maturation history of Carboniferous source rocks indicates that the temperature rapidly reached the threshold of hydrocarbon generation during the Late Carboniferous and has never achieved such a high level since *** characteristic resulted in the early maturation of hydrocarbons in Carboniferous source ***,the results reveal that hydrocarbon maturities are different among various tectonic units in Junggar *** kerogen either rapidly broke through the dry gas period so that cracking of gas occurred or remained in the oil maturation window forming oil reservoirs,which depended on the tectonic background and depositional *** this study,we present the thermal and hydrocarbon maturation history since the Carboniferous,which has important implications for further hydrocarbon exploration in Junggar Basin.

关键词： Thermal history Hydrocarbon maturation modeling Vitrinite reflectance Carboniferous Source rocks Junggar Basin

Loss Analysis of magnetic Gear with Slotted in magnetic modulation Ring

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CES Transactions on Electrical machines and Systems 2023年第1期7卷 110-117页

作者： Can Tan Wei Liu Yingying rao Weizhao Tang Libing Jing the College of Electrical Engineering and New Energy China Three Gorges UniversityYichang443002China

In order to improve the operation efficiency of coaxial magnetic gear(CmG),in this paper,a CmG model with slotted in magnetic modulation ring is *** this model,the permanent magnets(Pms)of internal and external rotors are distributed in Halbach array,the inner rotor Pms are equally divided into 3 small pieces,and the outer rotor Pms are equally divided into 2 small *** the same time,the static magnetic modulation ring iron blocks are slotted,each iron block has 3 slots,the width of the slot is 0.4°,and the depth of the single side slot is ***,a two-dimensional model is established,and the eddy current loss and iron loss of the model are optimized,compared with the conventional CmG model,it is found that the changed pattern can increase the internal and external output torque by 4%and 4.12%,*** eddy current loss is reduced by 66.57%,and the iron loss is reduced by 8.9%,which significantly improve the operation efficiency of the CmG.

关键词： Coaxial magnetic gear Electromagnetic torque Halbach array Loss Slotting

Record Flood-Producing Rainstorms of July 2021 and August 1975 in Henan of China:Comparative Synoptic Analysis Using ERA5

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Journal of meteorological Research 2022年第6期36卷 809-823页

作者： Jian rao Jin XIE Yong CAO Suxing ZHU Qian LU Key Laboratory of meteorological Disaster of ministry of Education(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of meteorological Disasters Nanjing University of Information Science&TechnologyNanjing210044China National meteorological Centre China Meteorological AdministrationBeijing100081China School of Atmospheric Sciences Nanjing University of Information Science&TechnologyNanjing210044China

This study compares two rainstorms that swept through Henan Province of China in July 2021 and August *** heavy rainfall and related synoptic systems and processes are diagnosed based on hourly ERA5 reanalysis data and precipitation observations from the China meteorological *** is estimated that most of the daily rainfall in Henan was caused by synoptic-scale precipitation,with the sub-synoptic convective rainfall intermittently dominating some of the hourly total *** rainband moved at about 2 m s^(-1) during the July 2021 rainstorm,whereas it was almost stationary during the August 1975 rainstorm when the heavy rainfall was concentrated in southern Henan.A double-typhoon circulation pattern with a subtropical high over the Bohai and Yellow Seas was observed during both *** heavy rainfall during the July 2021 event was controlled remotely by Typhoons Cempaka and In-Fa,which provided a path for the transport of moisture via the southerly jet associated with Typhoon Cempaka and the easterly(or southeasterly)jet associated with Typhoon *** rainstorm in August1975 was caused more directly by Typhoon Nina,which made landfall in Fujian Province and moved toward Henan *** rainfall around the inverted trough of the motionless Typhoon Nina produced a cumulative *** two rainstorms also differed in their circulation patterns in the upper *** intrusion of high potential vorticity air over Central China occurred in the July 2021 extreme rainstorm,whereas the South Asian high was enhanced and biased further north during the August 1975 *** analysis showed that the northward and westward transport of moisture took place during the July 2021 rainstorm,whereas the westward transport of moisture from the east of Henan dominated near the inverted trough of Typhoon Nina during the August 1975 rainstorm.

关键词： August 1975(“75.8”)rainstorm July 2021(“21.7”)rainstorm Henan rainstorms double-typhoon circulation patterns

Enrichment of Nb and Ti from carbonatite pyrochlore ore via calcining-slaking followed by gravity separation

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International Journal of mining Science and Technology 2022年第3期32卷 615-626页

作者： Shuhui Zhang mingjun rao Rendong Xiao Jinxiang You Guanghui Li Tao Jiang School of minerals Processing&Bioengineering Central South UniversityChangsha 410083China

In this work,a novel process consisting of calcining-slaking followed by gravity separation for the enrichment of niobium(Nb)and titanium(Ti)from carbonatite pyrochlore ore was proposed,validated and compared with the current mainstream flotation *** calcining of the pyrochlore ore,within which the carbonates were transformed into ***,when the calcined ore was slaked,lime was transformed into hydroxide with fine particles which were amenable to gravity *** calcining at 900℃for 60 min,slaking at 90℃for 10 min with a liquid–solid ratio of 3:1(mL/g),approximately 40%of tailings can be removed by gravity separation,the recoveries of Nb and Ti were 94.7%and 91.0%,and the enrichment ratios of Nb and Ti were 1.61 and 1.43,*** new approach exhibits high separation efficiency of carbonate gangue minerals and valuable minerals,satisfactory recoveries of niobium as well as titanium can be achieved.

关键词： Niobium Titanium Pyrochlore ore Calcination Gravity separation

Spatiotemporal variations of benthic macrofaunal community in the Xiamen Amphioxus Nature Reserve, eastern South China Sea

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Acta Oceanologica Sinica 2020年第6期39卷 10-18页

作者： Yiyong rao Lizhe Cai Wenjun Li Xinwei Chen Deyuan Yang College of the Environment and Ecology Xiamen UniversityXiamen 361102China Key Laboratory of the Coastal and Wetland Ecosystems(Xiamen University) Ministry of EducationXiamen 361102China

In order to realize the spatiotemporal variations of benthic macrofaunal communities at the"Amphioxus Sand"habitat,six surveys including four seasons and three consecutive summers(i.e.,2014,2015 and 2016)were conducted in two core sites,i.e.,Huangcuo(HC)and Nanxian-Shibaxian(NX),in the Xiamen Amphioxus Nature Reserve in China.A total of 155 species of macrofauna were recorded,therein,polychaetes were dominant in terms of species number and *** spatiotemporal variations of macrofaunal communities were *** density of polychaetes and the biomass of molluscs in the HC site were higher than those in the NX *** were more diverse and abundant in the cold seasons(winter and spring)than that in the warm seasons(summer and autumn).The annual variations of macrofaunal communities may be attributed to the changes in sediment texture among the three years of the *** variations in macrofaunal communities were mainly related to the proportion of polychaetes within the *** addition,the density of amphioxus(include Branchiostoma japonicum and ***)was negatively correlated to that of polychaetes,bivalves,and *** was less likely to be found in the sediments with higher silt and clay *** biotic indices including margaref’s richness index(d),Peilou’s evenness index(J′),Shannon-Wiener diversity index(H′),AmBI and m-AmBI were calculated in the present *** seems suitable in assessing benthic health at the"Amphioxus Sand"habitat,and a potential risk of ecological health in Xiamen Amphioxus Nature Reserve should be aware.

关键词： spatiotemporal variation Amphioxus Sand benthic macrofaunal community Branchiostoma biotic index

Friction stir surfacing of cast A356 aluminiumesilicon alloy with boron carbide and molybdenum disulphide powders

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Defence Technology（防务技术） 2015年第2期11卷 140-146页

作者： R.SRINIVASU A.SAmBASIVA rao G.mADHUSUDHAN REDDY K.SRINIVASA rao Department of metallurgical Engineering Andhra University Defence metallurgical Research Laboratory

Good castability and high strength properties of Ale Si alloys are useful in defence applications like torpedoes,manufacture of missile bodies,and parts of automobile such as engine cylinders and *** wear resistance of the alloys is major limitation for their *** stir processing(FSP) is a recognized surfacing technique as it overcomes the problems of fusion route surface modification *** in view of the requirement of improving wear resistance of cast aluminiumesilicon alloy,friction stir processing was attempted for surface modification with boron carbide(B4C) and molybdenum disulfide(mo S2) ***,micro compositional analysis,hardness and pin-on-disc wear testing were used for characterizing the surface composite *** study revealed breaking of coarse silicon needles and uniformly distributed carbides in the A356 alloy matrix after *** and uniformity in hardness was obtained in surface composite *** wear resistance was achieved in friction stir processed coating with carbide *** of solid lubricant mo S2 powder was found to improve wear resistance of the base metal significantly.

关键词： A356合金二硫化钼堆焊技术硅合金钼粉末碳化硼摩擦铸铝