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Magnetochronology of Mid-Miocene mammalian fauna in the Lanzhou Basin,northeastern Tibetan Plateau:Implications for Asian mammal migration

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Geoscience Frontiers 2020年第4期11卷 1337-1344页

作者： Peng Zhang hong Ao Andrew P.Roberts Yongxiang Li qiang sun Jianhui Zhang Pengfei sun Xiaoke qiang State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China Open Studio for Oceanic-Continental Climate and Environment Changes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266061China School of Geography and Information Engineering China University of GeosciencesWuhan 430074China Research School of Earth Sciences Australian National UniversityCanberraACT2601Australia State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China College of Geology and Environment Xi’an University of Science and TechnologyXi’an 710054China School of Earth Science and Engineering Hebei University of EngineeringHandan 056038China

The Quantougou(QTG) Fauna in central Lanzhou Basin is an important late Mid-Miocene fauna on the northeastern Tibetan Plateau margin,but its numerical age remains a matter of ***,we present a new magnetostratigraphic record for a fluvio-lacustrine section to further constrain the age of the QTG *** suggest that the studied section spans from polarity chrons C5Cn.2n to C5 n.2n or C5 An.1n,with ages of ca.16.5 Ma to 10 Ma or 16.5 Ma to 12 *** QTG Fauna is located at the top of polarity chron C5r.3 r or C5 Ar.2 r,which corresponds to an age of 11.7 Ma or 12.8 Ma for the ***,the associated Myocricetodontinae(a subfamily of Gerbillidae,Rodentia) is suggested to have appeared in the Lanzhou Basin at 11.7 Ma or 12.8 Ma,which is the oldest Myocricetodontinae in East Asia but is still much younger than the ~20 Ma appearance of this subfamily in West and South *** age data support the interpretation that East Asian Myocricetodontinae originated from South *** QTG fauna further suggest a dry and open grassland environment,which is consistent with global cooling after the Mid-Miocene Climatic Optimum.

关键词： Magnetostratigraphy Miocene Tibetan plateau Lanzhou Basin Mammal migration Myocricetodontinae

Generation of Cenozoic intraplate basalts in the big mantle wedge under eastern Asia

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Science China Earth Sciences 2018年第7期61卷 869-886页

作者： Yigang XU hongyan LI Lubing hong Liang MA qiang MA Mingdao sun State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China School of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The roles of subduction of the Pacific plate and the big mantle wedge(BMW) in the evolution of east Asian continental margin have attracted lots of attention in past years. This paper reviews recent progresses regarding the composition and chemical heterogeneity of the BMW beneath eastern Asia and geochemistry of Cenozoic basalts in the region, with attempts to put forward a general model accounting for the generation of intraplate magma in a BMW system. Some key points of this review are summarized in the following.(1) Cenozoic basalts from eastern China are interpreted as a mixture of high-Si melts and low-Si melts. Wherever they are from, northeast, north or south China, Cenozoic basalts share a common low-Si basalt endmember, which is characterized by high alkali, Fe_2O_3~T and TiO_2 contents, HIMU-like trace element composition and relatively low ^(206)Pb/^(204)Pb compared to classic HIMU basalts. Their Nd-Hf isotopic compositions resemble that of Pacific Mantle domain and their source is composed of carbonated eclogites and peridotites. The high-Si basalt endmember is characterized by low alkali, Fe_2O_3~T and TiO_2 contents, Indian Mantle-type Pb-Nd-Hf isotopic compositions, and a predominant garnet pyroxenitic source. High-Si basalts show isotopic provinciality, with those from North China and South China displaying EM1-type and EM2-type components, respectively, while basalts from Northeast China containing both EM1-and EM2-type components.(2) The source of Cenozoic basalts from eastern China contains abundant recycled materials, including oceanic crust and lithospheric mantle components as well as carbonate sediments and water. According to their spatial distribution and deep seismic tomography, it is inferred that the recycled components are mostly from stagnant slabs in the mantle transition zone,whereas EM1 and EM2 components are from the shallow mantle.(3) Comparison of solidi of garnet pyroxenite, carbonated eclogite and peridotite with regional geoth

关键词： Big mantle wedge Subduction of west Pacific plate Cenozoic intraplate basalt Eastern China East Asia

A Local Statistical Structural Model for Amorphous Solids

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Chinese Physics Letters 2013年第12期30卷 87-90页

作者： sun qiang Key Laboratory of Orogenic Belts and Crustal Evolution(Ministry of Education) School of Earth and Planetary SciencesPeking UniversityBeijing 100871

From Raman spectroscopic study on OH stretching bands,the local statistical interpretation for water structure is *** to the closely structural relationship between amorphous solids and liquids,the structural model is extended to investigate the amorphous solids,which indicates that various intensity of potential can be expected around an atom(molecule).From this,a local statistical order parameter is proposed to understand the short-range order and long-range *** order parameter is influenced by the cooling rate in the glass formation,which means that glass is formed with a slower cooling rate,and has higher structural *** amorphous solids,the geometric topology is closely related to chemical bonding type,such as covalent bond and metallic bond.

关键词： amorphous solids structural

Supporting feature model refinement with updatable view

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Frontiers of Computer Science 2013年第2期7卷 257-271页

作者： Bo WANG Zhenjiang HU qiang sun Haiyan ZHAO Yingfei XIONG WeiZHANG hong MEI Key Laboratory of High Confidence Software Technologies Peking UniversityChina Beijing 100871 GRACE Center National Institute of InformaticsJapan Tokyo 101843 Department of Computer Science Shanghai Jiao Tong UniversityChina Shanghai 200240

In the research of software reuse, feature models have been widely adopted to capture, organize and reuse the requirements of a set of similar applications in a software do- main. However, the construction, especially the refinement, of feature models is a labor-intensive process, and there lacks an effective way to aid domain engineers in refining feature models. In this paper, we propose a new approach to support interactive refinement of feature models based on the view updating technique. The basic idea of our approach is to first extract features and relationships of interest from a possibly large and complicated feature model, then organize them into a comprehensible view, and finally refine the feature model through modifications on the view. The main characteristics of this approach are twofold： a set of powerful rules （as the slicing criterion） to slice the feature model into a view auto- matically, and a novel use of a bidirectional transformation language to make the view updatable. We have successfully developed a tool, and a nontrivial case study shows the feasi- bility of this approach.

关键词： feature model refinement slicing bidrectionaltransformation

经口底入路腔镜与开放甲状腺切除术治疗良性甲状腺结节性疾病的临床研究

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中国当代医药 2017年第5期24卷 34-36页

作者：陈晓英韩宏斌陈强孙红戈王宇翔晏党辽宁省辽河油田总医院肿瘤诊治中心辽宁盘锦124010

目的探讨经口底入路腔镜甲状腺切除术与传统开放甲状腺切除术治疗良性甲状腺病变的临床效果。方法选取2013年11月~2015年8月我院收治的甲状腺腺瘤或结节性甲状腺肿患者62例,按照患者意愿分为观察组和对照组。观察组25例采用经口底入路... 详细信息

目的探讨经口底入路腔镜甲状腺切除术与传统开放甲状腺切除术治疗良性甲状腺病变的临床效果。方法选取2013年11月~2015年8月我院收治的甲状腺腺瘤或结节性甲状腺肿患者62例,按照患者意愿分为观察组和对照组。观察组25例采用经口底入路腔镜手术治疗;对照组37例采用传统开放甲状腺切除治疗。比较两组手术时间、术中出血量、术后引流量、住院时间、术后并发症发生率及美观满意度。结果观察组甲状腺切除术均成功完成,围术期无明显并发症,观察组术中出血为(25±5)ml,术后住院时间为(4.4±0.6)d;对照组术中出血量为(35±5)ml,术后住院时间为(6.6±0.7)d,差异有统计学意义(P0.05)。结论与传统开放甲状腺切除术比较,经口底入路甲状腺切除术具有切口隐蔽、术后恢复快的优点,同样安全且可靠。

关键词：甲状腺切除术经口底入路腔镜

Correlation between microstructure and impact toughness of weld heat-affected zone in 5 wt.% manganese steels

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Journal of Iron and Steel Research International 2019年第7期26卷 761-770页

作者： Jun-hui Li hong-hong Wang qiang Luo Li Li Chao sun R.D.K. Misra The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Wuhan 430081 Hubei China Research Institute of Nanjing Iron and Steel Co. Ltd. Nanjing 210035 Jiangsu China Laboratory for Excellence in Advanced Steel Research Department of Metallurgical Materials and Biomedical Engineering University of Texas at El Paso El Paso TX 7996& USA

The microstructure in welding heat-affected zones of 5 wt.% manganese steels was studied, and its effect on impact toughness was analyzed. The simulated coarse-grained heat-affected zone (CGHAZ) had the lowest impact toughness of ~39 J at — 40℃ because of coarse-grained structure and least volume fraction of retained austenite (RA) of 1.2 vol.%. The impact toughness of simulated intercritical heat-affected zone (ICHAZ) and fine-grained heat-affected zone (FGHAZ) were ~165 and ~45 J, respectively, at — 40℃. The effective grain size of simulated FGHAZ was smaller than that of the simulated ICHAZ. Furthermore, microstructural investigation revealed that the simulated FGHAZ and ICHAZ had similarity in volume fraction and stability of RA. However, tempered martensite was present in ICHAZ and absent in FGHAZ. It is proposed that the presence of tempered martensite contributed to good impact toughness in simulated ICHAZ.

关键词： 5 wt.% manganese steel Welding heat-affected zone Retained austenite Tempered martensite Impact toughness

Relationship Between Polyamines Metabolism and Cell Death in Roots of Malus hupehensis Rehd. Under Cadmium Stress

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Journal of Integrative Agriculture 2012年第7期11卷 1129-1136页

作者： JIANG Qian-qian YANG hong-qiang sun Xiao-li LI qiang RAN Kun ZHANG Xin-rong College of Horticulture Science and Engineering Shandong Agricultural University Tai'an 2 71018 P.R. China State Key Laboratory of Crop Biology Shandong Agricultural University Tai'an 271018 P.R.China

The free putrescine （Put） content, the hydrogen peroxide （H202） content and the polyamine oxidase （PAO） activity in roots of Malus hupehensis Rehd. var. pinyiensis Jiang （PYTC） were significantly increased, and reached its peak at 1, 2 and 6 h, respectively, under cadmium treatment. The free spermine （Spin） and spermidine （Spd） contents were dramatically decreased, and reached the minimum value at 4-6 h, then remained relatively stable. The change in total free polyammes （PAs） content was consistent with that of free Put. The number of root dead cells was gradually increased after treatment for 24 h, and the typical characteristics of programmed cell death （PCD） were displayed at 48 h. Throughout the Cd treatment process, changes in PAs metabolism appeared to be prior to cell death increase, and the H2O2 content was always maintained at a high level. These results indicated that polyamines could initiate cell death by generating H2O2 in roots of Malus hupehensis Rehd. under CdSO4 stress.

关键词： Malus hupehensis Rehd. cadmium cell death polyamines metabolism

Effect of reductant type on the embedding direct reduction of beach titanomagnetite concentrate

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International Journal of Minerals,Metallurgy and Materials 2019年第2期26卷 152-159页

作者： Yong-qiang Zhao Ti-chang sun hong-yu Zhao Chao Chen Xiao-ping Wang Key Laboratory for High-Efficient Mining and Safety of Metal Mines Ministry of Education University of Science and Technology Beijing School of Civil and Resource Engineering University of Science and Technology Beijing

Iron and titanium were recovered from beach titanomagnetite(TTM) concentrate by embedding direct reduction and magnetic separation. The reduction products and the effects of the reductant type and reduction temperature on the reduction behavior were investigated. The results showed that the reduction of TTM concentrate was strongly related to the gasification reactivity of the reductant. Bitumite presented a better product index than wheat-straw biochar and coke, mainly because the gasification reactivity of bitumite was better than that of the other reductants. In addition, high temperatures were not beneficial to embedding direct reduction because of the emergence of a molten phase and iron-joined crystals, which in turn reduced the diffusion rate of the reducing gas and impeded the reduction reaction in the central area of the roasted briquette. The use of bitumite as the reductant at a C/Fe molar ratio of 1.4 and a reduction temperature of 1200°C for 120 min resulted in direct-reduction iron powder assaying 90.28 wt% TFe and 0.91 wt% TiO_2 with an iron recovery of 91.83% and titanium concentrate assaying 46.01 wt% TiO_2 with a TiO_2 recovery of 91.19%. Titanium existed mainly in the form of anosovite and ilmenite in the titanium concentrate.

关键词： beach titanomagnetite concentrate embedding direct reduction magnetic separation reductant reduction temperature

Cavitation performance of high-speed centrifugal pump with annular jet and inducer at different temperatures and void fractions

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Journal of Hydrodynamics 2019年第1期31卷 93-101页

作者： Jin Jiang Yan-hui Li Chong-yan Pei Lin-lin Li You Fu hong-gui Cheng qiang-qiang sun Key Laboratory of Hydraulic Machinery Transient MOEWuhan UniversityWuhan 430072China Science and Technology on Scramjet Laboratoty The 31st Research Institute of CASICBeijing 100074China

The cavitation is very common in a centrifugal pump,especially when the speed is very high,and it seriously influences the centrifugal pump *** this investigation,the RNG k-ε turbulence model and the cavitation model with consideration of the mass transferring are first used to simulate the cavitation performance of the high-speed centrifugal pump without taking any measure for improving the pump cavitation *** calculation results reveal that a number of bubbles appear in the centrifugal pump flow channel,and the head as well as the flow rate of the high-speed centrifugal pump are far from its design *** cavitation performance can be improved effectively by arranging a variable pitch inducer and adopting an annular nozzle *** flow field analysis of the pump is conducted to obtain the suitable working temperature distribution at different void *** one hand,with the same void fraction,the head of the centrifugal pump drops slowly with the increase of ***,when the temperature exceeds 90°C,the head of the pump drops *** the other hand,at the constant temperature,the higher the void fraction,the worse the cavitation *** research conducted under different temperatures and void fractions provides some guidance for designing an effective high-speed centrifugal pump.

关键词： High-speed centrifugal pump cavitation performance inducer annular nozzle void fraction