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He–Ar Isotopic Tracing of Pyrite from Ore-forming Fluids of the Sanshandao Au Deposit, Jiaodong Area

Acta Geologica Sinica(English Edition) 2019年第6期93卷 1797-1807页

作者： han Zhenyu YU xiaowei LI Shoujun Tian Jingxiang WANG Zhongliang YU Xiaojing WANG Ligong College of Earth Science&Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China Yantai Natural Museum YantaiShandong 264000China Shandong Institute of Geological Survey Ji’nan 250014China Shandong Institute of Geological Sciences Ji’nan 250014China Key Laboratory of Gold Mineralization Process and Resources Utilization Ministry of Land and Resources Ji’nan 250014China Key Laboratory of Metal Mineralization Geological Processes and Resources Utilization in Shandong Province Ji’nan 250014 China State Key Laboratory of Geological Process and Mineral Resources China University of GeosciencesBeijing 100083 China The third Exploration Institute of Geology and Mineral Resources of Shandong Province YantaiShandong 264000China

The Sanshandao Au deposit is located in the famous Sanshandao metallogenic belt,Jiaodong *** date,accumulative Au resources of 1000 t have been identified from the *** is a world-class gold deposit with Au mineralization hosted in Early Cretaceous Guojialing-type ***,studies on the genesis and ore-forming element sources of the Sanshandao Au deposit are *** and Ar isotopic analyses of fluid inclusions from pyrite(the carrier of Au)indicate that the fluid inclusions have 3 He/4 He=0.043–0.21 Ra with an average of 0.096 Ra and 40 Ar/36 Ar=488–664 with an average of *** values represent the initial He and Ar isotopic compositions of ore-forming fluids for trapped fluid *** comparison of H–O isotopic characteristics combined with deposit geology and wall rock alteration reveals that the ore-forming fluids of the Sanshandao Au deposit show mixed crust–mantle origin characteristics,and they mainly comprise crust-derived fluid mixed with minor mantle-derived fluid and meteoric water during the uprising *** ore-forming elements were generally sourced from pre-Cambrian meta-basement rocks formed by Mesozoic reactivation and mixed with minor shallow crustal and mantle components.

关键词： Sanshandao Au deposit He and Ar isotopes fluid inclusions crustal fluid mantle-derived fluid

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Atomic and electronic structures of p-type dopants in 4H-SiC

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Chinese Physics B 2021年第9期30卷 445-450页

作者： Lingyan Lu han Zhang xiaowei Wu Jing Shi Yi-Yang Sun Department of Physics Jiangxi Normal UniversityNanchang 330022China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China

Using hybrid density functional calculation,we study the atomic and electronic structures of p-type dopants,B,Al and Ga,in *** B,depending on the growth condition,it can occupy both Si and C *** contrast,Al and Ga on the C sites exhibit too high formation energy to exist in a significant *** 4H-SiC,there exist two types of Si sites in wurtzite-like and zincblende-like local coordination,*** calculations suggest that the dopant atoms have negligible preference occupying the two *** neutral charge state,all the dopants exhibit significant distortions from the structure in the negatively charged *** most cases,our calculations yield three distorted structures,in which the most stable one has the dopant atom displaced along its bond with one of the surrounding equatorial Si or C atoms,lowering the C_(3v) symmetry to C_(s) symmetry(i.e.,a mirror symmetry only).Among the three dopant elements,Al on Si sites exhibits overall the lowest formation energy and the shallowest acceptor ***,it is not a hydrogenic dopant with the acceptor level 0.12 eV above the valence band maximum based on calculation using a 400-atom *** corresponding defect state exhibits apparent localization along the[0001]direction,but it is relatively delocalized in the(0001)plane.

关键词： wide band gap semiconductors p-type doping SiC density functional theory

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Effect of competition on spatial patterns of oak forests on the Chinese Loess Plateau

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Journal of Arid Land 2017年第1期9卷 122-131页

作者： KANG Di DENG Jian QIN xiaowei HAO Fei GUO Shujuan han Xinhui YANG Gaihe College of Forestry Northwest A&F University Yangling 712100 China The Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province Yangling 712100 China College of Agronomy Northwest A&F University Yangling 712100 China Spice and Beverage Institute Research Chinese Academy of Tropical Agricultural Sciences Wanning 730070 China Yunnan Baiyao Group CO. LTD Kunming 650500 China

Reforestation or natural forest regeneration is an alternative measure for controlling soil erosion in degraded land on the Chinese Loess Plateau（CLP）. However, our understanding of the temporal dynamics and the spatial patterns of forest regeneration remains inadequate. Two oak forests at different development stages were investigated to determine the spatial patterns of competitions（intraspecies and interspecies） during different successional stages. The intraspecies and interspecies spatial relationships among different tree diameters at breast height were analyzed at multiple scales by Kriging interpolation method and univariate and bivariate O-ring statistics. Our analytical results indicated that self-correlation and competition intensity were relatively high between oak and pine trees in the early development stage of oak forests due to their clumped distributions of heavy seeds. Birch trees had a lower competition in comparison to oak trees although birch was the dominant species. Therefore, asymmetric competition of oak trees was most likely to have led to their edge dispersal and their success in replacing the pioneer species. Asymmetric competition means that larger individuals obtained a disproportionately large share of the resources and suppressed the growth of smaller individuals. Kriging interpolation analysis showed a tendency towards homogenization caused by interspecies competition during the succession of oak forests. Our results demonstrated that the competition was the driving factor in the spatial distribution of oak forests on the CLP.

关键词： arid and semi-arid region forest regeneration competition spatial pattern oak forests

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Divergent asymmetric synthesis of azaarene-functionalized cyclic alcohols through stereocontrolled Beckwith-Enholm cyclizations

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Science China Chemistry 2021年第9期64卷 1522-1529页

作者： Zhanghong Guo xiaowei Chen Hao Fang xiaowei Zhao Zhiyong Jiang International Scientific and Technological Cooperation Base of Chiral Chemistry Henan UniversityKaifeng475004China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang453007China

The first enantioselective Beckwith-Enholm cyclization reaction is reported *** cooperative photoredox and chiral hydrogen-bonding catalysis mediated by visible light,cyclization of carbonyls with azaarene-based olefins as a new reaction system offers a general and divergent synthetic pathway to furnish a variety of highly valuable enantioenriched azaarenefunctionalized carbocyclic and heterocyclic alcohols,which bear adjacent 1,2-or nonadjacent 1,3-stereocentres on distinct cyclic frameworks,in high yields and enantio-and *** good compatibility of various azaarenes and carbonyls as well as the diversity of cyclic structures of the products underscores the generality of the catalysis *** addition to the ability to precisely introduce deuterium into molecules in an enantioselective manner,the considerable synthetic value of this method includes the excellent antioxidant stress potential of the *** particular,molecule 29 was determined to be a promising lead compound for antioxidant stress drug design.

关键词： photoredox catalysis asymmetric catalysis Beckwith-Enholm cyclizations azaarenes antioxidant stress

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Angle Scattering Method for Soot Concentration Measurement under Ultra-Low Emissions Condition

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Energy Engineering 2022年第2期119卷 511-522页

作者： Bin Yang Xingchen Zhu Jie Deng Xiaoxu Guo Jinke han xiaowei Liu School of Energy and Power Engineering Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power EngineeringUniversity of Shanghai for Science and TechnologyShanghai200093China State Key Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan430074China

Aiming at the problem of soot concentration measurement under ultra-low emission conditions,a forward small angle soot concentration measurement method is *** a typical boiler emission of 0.1μm-3.0μm bimodal distribution soot as an object,the particle scatter simulation calculation under different parameters is carried out,and the influence of detection angle and particle size on the angular scatteringmeasurement of ultra-low emission soot is *** influence of detection angle and particle size on the angular scatteringmeasurement of ultra-lowemission soot is ***,thewavelength of incident light is 650 nm,and the forward detection angle parameter is 15◦for the design of forward small angle soot concentration measurement *** experimental system for measuring soot with standard concentration is *** of particle concentration measurement of 1.0μm and 3.0μm under ultra-low emission conditions are carried *** results show that the average deviation of soot concentration measurement is less than 0.10 mg/m3 under the condition of ultra-low emission by using 15◦of forward detection,which provides an effective way for monitoring ultra-low emission soot concentration in coal-fired power plants.

关键词： Emission monitoring ultra-low emission soot concentration angular scattering

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泵前动脉压与泵控血流速比值的绝对值对自体动静脉内瘘功能的预测研究

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护理研究 2022年第6期36卷 952-958页

作者：孙春艳宋利田秀兰韩晓苇蓝丽娟周丽芳钟咪陈迎归赵宜娜全梓林符霞广东省人民医院(广东省医学科学院) 广东510080 深圳市中医院深圳市人民医院

目的:明确泵前动脉压与泵控血流速比值的绝对值(|Pa/Qb|)对自体动静脉内瘘(AVF)功能不良的影响及其安全范围,探究|Pa/Qb|的影响因素。方法:回顾性分析2018年1月—2019年1月3所三级甲等医院血液透析中心490例长期血液透析病人临床资料,评... 详细信息

关键词：泵前动脉压泵控血流速自体动静脉内瘘功能不良血液透析护理

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调和营卫法治疗心血管疾病研究进展

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辽宁中医药大学学报 2021年第1期23卷 46-49页

作者：韩晓伟周国锋王永成马度芳杨金龙李晓山东中医药大学山东济南250014 山东中医药大学附属医院山东济南250014

营卫与心关系紧密。心者主血脉,营卫生血行血。营卫运行失常,血脉瘀滞,内生痰浊水饮,导致心血瘀阻;营卫虚损,伤及心之气血阴阳,均可导致心系疾病的发生。调和营卫法作为心血管疾病的重要治疗方法,广泛应用于心血管疾病的治疗。现代研究... 详细信息

营卫与心关系紧密。心者主血脉,营卫生血行血。营卫运行失常,血脉瘀滞,内生痰浊水饮,导致心血瘀阻;营卫虚损,伤及心之气血阴阳,均可导致心系疾病的发生。调和营卫法作为心血管疾病的重要治疗方法,广泛应用于心血管疾病的治疗。现代研究表明调和营卫法具有缓解内皮功能障碍、调节自主神经重构、重塑肠道菌群、抗炎、逆转纤维化、抑制氧化应激和改善心功能等作用,在治疗冠心病、高血压病、心力衰竭、心律失常等心血管疾病中取得显著疗效。该文通过将调和营卫法对于心血管疾病的基础研究及临床应用进行总结,分析调和营卫法干预心血管疾病的作用机制,从而为心血管疾病的防治提供借鉴。

关键词：调和营卫法心血管疾病研究进展

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泵站出水池-无压隧洞过渡段体型优化研究

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水资源与水工程学报 2018年第4期29卷 138-142页

作者：王月华王斌吴德忠韩晓维张鸿清王自明浙江省水利河口研究院浙江杭州310020 余姚市水利局浙江余姚315400

泵站出水池到无压隧洞过渡段体型对隧洞的过流能力、沿程水面线及局部水头损失影响显著。针对某泵站工程过渡段的水流特性问题,采用比尺为1∶25物理模型对该过渡段进行了优化研究,延长了过渡段长度,增加了边墙扭曲段。研究发现:模型改进... 详细信息

泵站出水池到无压隧洞过渡段体型对隧洞的过流能力、沿程水面线及局部水头损失影响显著。针对某泵站工程过渡段的水流特性问题,采用比尺为1∶25物理模型对该过渡段进行了优化研究,延长了过渡段长度,增加了边墙扭曲段。研究发现:模型改进后,过流能力增加,水流平稳;局部水头系数从原设计的0.057~0.111减小至0.051~0.111;中心线水面线的纵向变化幅度减小。通过各项指标表明,优化后的过渡段比原设计方案显现出更为优良的特性,提出的优化设计方法可为其他类似工程提供借鉴经验。

关键词：泵站出水池无压隧洞过渡段体型优化模型试验

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矮小症病因及临床特征分析

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临床儿科杂志 2019年第1期37卷 39-42页

作者：韩晓伟董治亚张婉玉马晓宇安静静肖园陆文丽王伟倪继红王德芬上海交通大学医学院附属瑞金医院儿内科上海200025

目的探讨矮小症的病因及临床特点。方法回顾分析1995年5月到2017年7月治疗的2 075例矮小症患儿的临床资料,分析病理性矮小和正常变异性矮小的病因及分布频率,分析生长激素缺乏症(GHD)、特发性矮小(ISS)、体质性生长延迟(CDG)和家族性矮... 详细信息

目的探讨矮小症的病因及临床特点。方法回顾分析1995年5月到2017年7月治疗的2 075例矮小症患儿的临床资料,分析病理性矮小和正常变异性矮小的病因及分布频率,分析生长激素缺乏症(GHD)、特发性矮小(ISS)、体质性生长延迟(CDG)和家族性矮小(FSS)的临床特征差异,分析严重矮小(身高SDS≤-3)及一般性矮小(身高SDS>-3)的病因差异。结果在2 075例诊断为矮小症的患儿中,1 719例(82.84%)为病理性矮小,其中GHD(38.60%)和ISS(22.02%)较为多见。356例(17.16%)为正常变异性矮小,FSS、CDG分别占10.70%和6.46%。4种常见儿童矮小症(GHD、ISS、CDG和FSS)的性别比、初诊年龄、身高标准差比值(SDS)、体质指数(BMI)、骨龄、骨龄延迟的差异均有统计学意义(P<0.01)。4种儿童矮小症均男性多于女性。GHD组身高SDS最低,CDG组最高;GHD组BMI最高,而CDG和ISS组则较低;GHD组骨龄延迟最多,而CDG组最少。严重矮小组中,完全性生长激素缺乏症、多垂体激素缺乏症、小于胎龄儿、特纳综合征、甲状腺功能减退症、Russell-Silver综合征的比例高于一般性矮小组;而部分性生长激素缺乏症、ISS、FSS、CDG的比例低于一般性矮小组。结论矮小症病因复杂,分析病因及临床特征有助于临床诊断和治疗。

关键词：病理性矮小正常变异性矮小矮小症

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Semi-empirical Formula of the Gas Gain in Limited Proportional Region

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Chinese Physics Letters 1991年第5期8卷 229-231页

作者： TANG xiaowei Institute of High Energy Physics Academia SinicaBeijing 100039

Considering the space charge effect on gas multiplication a semi-empirical formula of the gas gain in limited proportional region is *** parameters of gas multiplication,the,threshold of limited proportional region Vs and the coefficient of space charge suppression B,are *** the experimental data the values of these parameters under different experimental conditions are obtained.

关键词： empirical charge semi

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