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Cyprininae phylogeny revealed independent origins of the Tibetan Plateau endemic polyploid cyprinids and their diversifications related to the Neogene uplift of the plateau

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Science China(Life Sciences) 2016年第11期59卷 1149-1165页

作者： xuzhen wang Xiaoni Gan Junbing Li Yiyu Chen Shunping He Key Laboratory of Aquatic Biodiversity and Conservation of the Chinese Academy of Sciences Institute of Hydrobiology Chinese Academy of Sciences

Origin and diversification of the Tibetan polyploid cyprinids(schizothoracins) may help us to explore relationships between diversification of the cyprinids and the Tibetan Plateau uplift. Cyprininae phylogeny was analyzed using mitochondrial and nuclear DNA sequences to trace origins of polyploidy and diversifications of schizothoracins. Ancestral states reconstruction for ploidy levels indicated that the Cyprininae was diploid origin and the schizothoracin clades tetraploid origins. There were two diversification rate shifts along with diversification of the cyprinine fishes in response to the Tibetan uplift. The unusual diversification shifts were located to branches subtending the clades of Tibetan polyploid cyprinids. Our analyses suggested that(i) phylogeny of Cyprininae recovered two independent origins of the Tibetan polyploidy schizothoracins;(ii) diversifications of the schizothoracins were closely related to the Neogene uplift of the Tibetan plateau in the following ways: the relatively ancient Late Oligocene-Middle Miocene adaptive radiation may be associated with the uplift of the southern Tibet and Himalaya; the Middle Miocene-Early Pleistocene lineage-specific diversification broadly coincident with major phase of the Neogene Tibetan uplift; and the most recent Pleistocene diversification shift in Schizothorax closely coincident with the successive Kunlun-Huanghe and Gonghe movements of the Tibetan uplift and the glaciation-induced climate oscillations on the plateau.

关键词： Cyprininae polyploid schizothoracins the Tibetan Plateau diversifications

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Integration of Desulfurization and Lithium-Sulfur Batteries Enabled by Amino-Functionalized Porous Carbon Nanofibers

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Energy & Environmental Materials 2023年第2期6卷 334-343页

作者： Minghui Sun xuzhen wang Yong Li Zongbin Zhao Jieshan Qiu State Key Lab of Fine Chemicals School of Chemical EngineeringLiaoning Key Lab for Energy Materials and Chemical EngineeringFaculty of ChemicalEnvironmental and Biological Science and TechnologyDalian University of TechnologyDalian 116024China College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China

Hydrogen sulfide(H_(2)S)is an industrial exhausted gas that is highly toxic to humans and the environment.Combining desulfurization and fabrication of cathode materials for lithium-sulfur batteries(LSBs)can solve this issue with a double benefit.Herein,the amino-functionalized lotus root-like carbon nanofibers(NH_(2)-PLCNFs)are prepared by the amination of electrospinning carbon nanofibers under dielectric barrier discharge plasma.Selective catalytic oxidation of H_(2)S to elemental sulfur(S)is achieved over the metalfree NH_(2)-PLCNFs catalyst,and the obtained composite S@NH_(2)-PLCNFs is further used as cathode in LSBs.NH_(2)-PLCNFs enable efficient desulfurization(removal capacity as high as 3.46 g H_(2)S g^(−1) catalyst)and strongly covalent stabilization of S on modified carbon nanofibers.LSBs equipped with S@NH_(2)-PLCNFs deliver a high specific capacity of 705.8 mA h g^(−1) at 1 C after 1000 cycles based on the spatial confinement and the covalent stabilization of electroactive materials on amino-functionalized porous carbon matrix.It is revealed that S@NH_(2)-PLCNFs obtained by this kind of chemical vapor deposition leads to a more homogeneous S distribution and superior electrochemical performance to the sample S/NH_(2)-PLCNF-M prepared by the traditional molten infusion.This work opens a new avenue for the combination of environment protection and energy storage.

关键词： amino-functionalization desulfurization lithium-sulfur batteries porous carbon nanofiber sulfur immobilization

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3D Carbon Frameworks for Ultrafast Charge/Discharge Rate Supercapacitors with High Energy‑Power Density

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Nano-Micro Letters 2021年第1期13卷 112-122页

作者： Changyu Leng Zongbin Zhao Yinzhou Song Lulu Sun Zhuangjun Fan Yongzhen Yang Xuguang Liu xuzhen wang Jieshan Qiu State Key Lab of Fine Chemicals School of Chemical EngineeringLiaoning Key Lab for Energy Materials and Chemical EngineeringDalian University of TechnologyDalian 116024People’s Republic of China College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China School of Materials Science and Engineering China University of PetroleumQingdao 266580ShandongPeople’s Republic of China Key Lab of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024People’s Republic of China

Carbon-based electric double layer capacitors(EDLCs)hold tremendous potentials due to their high-power performance and excellent cycle stability.However,the practical use of EDLCs is limited by the low energy density in aqueous electrolyte and sluggish diffusion kinetics in organic or/and ionic liquids electrolyte.Herein,3D carbon frameworks(3DCFs)constructed by interconnected nanocages(10-20 nm)with an ultrathin wall of ca.2 nm have been fabricated,which possess high specific surface area,hierarchical porosity and good conductive network.After deoxidization,the deoxidized 3DCF(3DCFDO)exhibits a record low IR drop of 0.064 V at 100 A g^−1 and ultrafast charge/discharge rate up to 10 V s^−1.The related device can be charged up to 77.4%of its maximum capacitance in 0.65 s at 100 A g^−1 in 6 M KOH.It has been found that the 3DCF-DO has a great affinity to EMIMBF4,resulting in a high specific capacitance of 174 F g^−1 at 1 A g^−1,and a high energy density of 34 Wh kg^−1 at an ultrahigh power density of 150 kW kg^−1 at 4 V after a fast charge in 1.11 s.This work provides a facile fabrication of novel 3D carbon frameworks for supercapacitors with ultrafast charge/discharge rate and high energy-power density.

关键词： 3D carbon frameworks Nanocages Ultrafast charge/discharge rate High energy-power density Supercapacitors

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青藏公路初建路线选定的因由抉择

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重庆交通大学学报（社会科学版） 2024年第3期24卷 137-144页

作者：王旭臻青海师范大学历史学院西宁810016 中共青海省委党史研究室西宁810000

青藏公路的修建受命于中华人民共和国成立初期中国共产党解放西藏、维护国家完整统一、支援边疆建设的关键时刻。然而,公路建设初期并非按照既定路线一以贯之修建到底,而是与解放军进军昌都解放西藏、中共中央西北局护送班禅返藏、国家... 详细信息

青藏公路的修建受命于中华人民共和国成立初期中国共产党解放西藏、维护国家完整统一、支援边疆建设的关键时刻。然而,公路建设初期并非按照既定路线一以贯之修建到底,而是与解放军进军昌都解放西藏、中共中央西北局护送班禅返藏、国家支援西藏建设发展三项重大任务紧密关联,在历经抢修西宁至黄河沿段公路,勘察西宁经玉树至拉萨段公路,修建格尔木至拉萨段、敦煌至拉萨段公路三次筑路勘测之后,最终改初始西宁经玉树至拉萨路线为西宁向西经格尔木再南折进藏至拉萨路线,修筑并贯通青藏公路。

关键词：青藏公路西藏运输总队慕生忠格尔木玉树

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Nitrogen-doped hierarchical porous carbon derived from metal–organic aerogel for high performance lithium–sulfur batteries

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Journal of Energy Chemistry 2017年第6期26卷 1282-1290页

作者： Han Zhang Zongbin Zhao Yang Liu Jingjing Liang Yanan Hou Zhichao Zhang xuzhen wang Jieshan Qiu State Key Lab of Fine Chemicals Liaoning Key Lab for Energy Materials and Chemical EngineeringPSU-DUT Joint Center for Energy ResearchSchool of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina School of Chemistry Dalian University of TechnologyDalian 116024LiaoningChina

Nitrogen-doped three-dimensional(3 D) porous carbon materials have numerous applications due to their highly porous structures, abundant structural nitrogen heteroatom decoration and low densities. Herein,nitrogen doped hierarchical 3 D porous carbons(NHPC) were prepared via a novel metal–organic aerogel(MOA), using hexamethylenetetramine(HMT), 1,3,5-benzenetricarboxylic acid and copper(II) as starting materials. The morphology, porous structure of the building blocks in the NHPC can be tuned readily using different amount of HMT, which makes elongation of the pristine octahedron of HKUST-1 to give rise to different aspect ratio rod-like structures. The as-prepared NHPC with rod-like carbons exhibit high performance in lithium sulfur battery due to the rational ion transfer pathways, high N-doped doping and hierarchical porous structures. As a result, the initial specific capacity of 1341 m A h/g at rate of 0.5 C(1 C = 1675 m A h/g) and high-rate capability of 354 m A h/g at 5 C was achieved. The decay over 500 cycles is 0.08% per cycle at 1 C, highlighting the long-cycle Li–S batteries.

关键词： Metal–organic aerogel N-doped porous carbon Lithium–sulfur batteries

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Diversification of Sisorid catfishes(Teleostei: Siluriformes)in relation to the orogeny of the Himalayan Plateau

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Science Bulletin 2016年第13期61卷 991-1002页

作者： Chuanjiang Zhou xuzhen wang Xiaoni Gan Yaping Zhang David M.Irwin Richard L.Mayden Shunping He Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of HydrobiologyChinese Academy of Sciences Key Laboratory of Freshwater Fish Reproduction and Development (Southwest University) Ministry of EducationSchool of Life Science Southwest University State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences College of Fisheries Henan Normal University Department of Laboratory Medicine and Pathobiology University of Toronto Banting and Best Diabetes Centre University of Toronto Department of Biology 3507 Laclede Ave. Saint Louis University

Sisorid catfishes are primarily limited in distribution to rivers of the Himalayan region and Tibetan Plateau. These species have external morphologies that are adapted for extremely fast-flowing riverine systems. Given the diversity of the group and the above qualities of these catfishes, this lineage serves as an ideal group for inferring the geological history of this region based on their phylogenetic relationships reflecting evolutionary history. We sequenced the complete mitochondrial genome and four nuclear genes of representative sisorids distributed across river systems in China. Phylogenetic analyses strongly support the monophyly of the Sisoridae and the glyptosternoids. An analysis of the reconstructed ancestral states derived from inferred genealogical relationships suggests that the evolution of this lineage was accompanied by convergent evolution in morphological traits that were presumably in response to environmental pressure involving the rapid flowing river system that were generated during the uplift of the Tibetan Plateau(UTP).Molecular dating indicates that the Chinese sisorids and the glyptosternoids originated at the later Miocene(*10.9–9.8Mya), and with further biogeographic analyses indicates that the species of Sisoridae likely originated from a widely distributed ancestor. Moreover, the divergence of the Sisoridae in China can be divided into two phases consistent with the UTP. All of these results indicate that the diversification and dispersal events in this lineage occurred as a result of drainage systems formed during and after the UTP in the late Miocene and Quaternary periods.

关键词：喜马拉雅地区西藏高原造山运动多样化亲缘关系分析河流系统线粒体基因组系统发育分析

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新中国成立初期青海探索实施民族区域自治的实践与经验(1949-1956)

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档案 2024年第1期 33-41页

作者：王旭臻姚三刚青海师范大学历史学院青海西宁810008 中共青海省委党史研究室青海西宁810000

民族区域自治制度是我国的一项基本政治制度,是中国特色解决民族问题的正确道路的重要内容和制度保障,在边疆民族地区的推行和实施是中华人民共和国成立后国家治理实现一体化的关键。根据中共中央在边疆民族地区开展工作应遵循的“慎重... 详细信息

民族区域自治制度是我国的一项基本政治制度,是中国特色解决民族问题的正确道路的重要内容和制度保障,在边疆民族地区的推行和实施是中华人民共和国成立后国家治理实现一体化的关键。根据中共中央在边疆民族地区开展工作应遵循的“慎重缓进”“稳步前进”原则方针,青海省以《共同纲领》《中华人民共和国民族区域自治实施纲要》《中华人民共和国宪法》三部立法为遵照,以“探索推进”“全面实施”“完善发展”三大阶段为划分,实事求是、因地制宜,结合当地建政实际情况,以及旧制度和政权组织影响程度、各少数民族参政议政情况、游牧地区藏族同胞成分占比情况、各民族分布聚居情况等,审慎对待新旧政权过渡转接问题,有序稳步推进实施民族区域自治。

关键词：青海少数民族聚居地区民族区域自治制度千百户制度

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Approximate Analysis of Power Offset over Spatially Correlated MIMO Channels

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Communications and Network 2009年第1期1卷 25-34页

作者： Guangwei YU xuzhen wang 不详

Power offset is zero-order term in the capacity versus signal-to-noise ratio curve. In this paper, approximate analysis of power offset is presented to describe MIMO system with uniform linear antenna arrays of fixed length. It is assumed that the number of receive antenna is larger than that of transmit antenna. Spatially Correlated MIMO Channel is approximated by tri-diagonal toeplitz matrix. The determinant of tri-diagonal toeplitz matrix, which is fitted by elementary curve, is one of the key factors related to power offset. Based on the curve fitting, the determinant of tri-diagonal toeplitz matrix is mathematically tractable. Consequently, the expression of local extreme points can be derived to optimize power offset. The simulation results show that approximation above is accurate in local extreme points of power offset. The proposed expression of local extreme points is helpful to approach optimal power offset.

关键词： MIMO multiplexing gain power offset high snr region toeplitz matrix

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CBL联合“互联网+教育平台”在危重病医学见习教学中的应用效果

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临床医学研究与实践 2024年第3期9卷 179-182页

作者：王旭珍万真南昌大学第一附属医院重症医学科江西南昌330000 南昌大学第一附属医院普外科江西南昌330000

目的探讨以病例为基础的学习(CBL)联合“互联网+教育平台”在危重病医学见习教学中的应用效果。方法选取2020年10月至12月及2021年10月至12月在南昌大学第一附属医院重症医学科见习的108名麻醉学本科生作为研究对象,其中2020年学生纳入... 详细信息

目的探讨以病例为基础的学习(CBL)联合“互联网+教育平台”在危重病医学见习教学中的应用效果。方法选取2020年10月至12月及2021年10月至12月在南昌大学第一附属医院重症医学科见习的108名麻醉学本科生作为研究对象,其中2020年学生纳入传统教学组(54名,传统教学法),2021年学生纳入联合教学组(54名,CBL联合“互联网+教育平台”教学)。比较两组的应用效果。结果两组的理论考试成绩比较,差异无统计学意义(P>0.05);联合教学组的操作考试成绩高于传统教学组,差异具有统计学意义(P<0.05)。联合教学组的教学质量、知识掌握、批判思维、学习兴趣、独立思考、师生交流、沟通能力评分高于传统教学组,差异具有统计学意义(P<0.05)。联合教学组的课前准备花费时间长于传统教学组,差异具有统计学意义(P<0.05)。结论CBL联合“互联网+教育平台”能够提高危重病医学见习教学质量,激发学生学习兴趣,提高临床思维能力及沟通技巧,但需要学生投入更多时间进行课前准备。

关键词：以病例为基础的学习学习通平台互联网+ 危重病医学以问题为基础的教学法

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50CrV4链板晶界氧化对疲劳强度的影响

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物理测试 2024年第1期42卷 44-49页

作者：张孟九谢爱军逄宁宁王绪珍王魁王俊杰青岛征和工业股份有限公司山东青岛266705

50CrV4作为优质的Cr-Mn-V系列合金弹簧钢,经过等温淬火+回火热处理后,获得下贝氏体+回火马氏体+少量残留奥氏体+弥散分布的颗粒状碳化物的复相组织。用50CrV4带钢制成的汽车正时齿形链链板,经过热处理后,保证高疲劳强度的同时,又兼具较... 详细信息

50CrV4作为优质的Cr-Mn-V系列合金弹簧钢,经过等温淬火+回火热处理后,获得下贝氏体+回火马氏体+少量残留奥氏体+弥散分布的颗粒状碳化物的复相组织。用50CrV4带钢制成的汽车正时齿形链链板,经过热处理后,保证高疲劳强度的同时,又兼具较好的耐磨性。但是由于50CrV4中Cr、Mn、V的存在,使得50CrV4过冷奥氏体较为稳定,在热轧卷板时,冷却不能过快,否则易出现马氏体和贝氏体,导致卷板过程中开裂,所以在高温区停留时间较长,不可避免地存在不同程度的晶界氧化,对晶界氧化程度不同的50CrV4带钢分别进行晶界氧化深度检测并冲裁成链板,在同样的热处理条件下,制作出成品链条,分别测试链条的拉力和疲劳强度,得出不同程度的晶界氧化对链条拉力和疲劳强度的影响,通过对比分析发现,纵向晶界氧化会造成链条拉力降低和链条疲劳强度降低,横向晶界氧化比纵向晶界氧化对链条的拉力的影响更严重,并且严重降低链条的疲劳强度。

关键词： 50CrV4钢晶界氧化疲劳强度链条拉力

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