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不同等级男子撑竿跳高运动员助跑及起跳的生物力学特征研究

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应用力学学报 2024年第4期41卷 956-972页

作者：李夏元刘飞亮夏正亮贾彬彬马远博伍勰刘宇上海体育学院“运动健身科技”省部共建教育部重点实验室上海200438 上海体育学院附属竞技体育学校上海200237 武汉体育学院运动训练学院武汉430079 莱布尼茨工作环境与人为因素研究中心心理与神经科学系多特蒙德44139

目的对不同等级男子撑竿跳高运动员质心速度、质心高度、地面反作用力和下肢关节力矩等生物力学指标的具体表现进行探讨,试图了解不同等级运动员的整体特征,并发现高水平运动员助跑及起跳过渡衔接的特点。方法使用大范围的三维动作捕捉... 详细信息

目的对不同等级男子撑竿跳高运动员质心速度、质心高度、地面反作用力和下肢关节力矩等生物力学指标的具体表现进行探讨,试图了解不同等级运动员的整体特征,并发现高水平运动员助跑及起跳过渡衔接的特点。方法使用大范围的三维动作捕捉系统以及3块测力台对优秀男子撑竿跳高运动员的运动学(200 Hz)和地面反作用力(2000 Hz)数据进行采集,分析比较了5名一级运动员、4名运动健将和3名国际级运动健将的生物力学指标。对国际级运动健将组、运动健将组和一级运动员组的同一生物力学指标两两之间采用非参数独立样本曼-惠特尼U单侧检验,对所有运动员倒2步、倒1步和起跳相应的生物力学指标两两之间采用非参数配对样本Wilcoxon符号秩单侧检验。结果不同等级撑竿跳高运动员助跑后两步和起跳的质心速度、质心高度、地面反作用力和下肢关节力矩等生物力学指标有显著性差异;倒2步、倒1步、起跳相应的生物力学指标之间有显著性差异。结论基于本研究的数据,男子撑竿跳高运动员表现出随等级而变化的生物力学特点,国际级健将运动员的质心速度、地面反作用力等指标体现了其较高的运动能力。倒2步、倒1步和起跳的质心速度、质心高度和地面反作用力等相应生物力学指标的显著差异反映了撑竿跳高技术动作的衔接特征,体现了撑竿跳高助跑向起跳过渡的运动学和动力学特点。

关键词：撑竿跳高运动表现生物力学地面反作用力关节力矩

高速铁路平面基础控制网复测数据处理及精度分析

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天津建设科技 2024年第4期34卷 9-13页

作者：王冰琰贾斌斌吕子丰吴晓华中铁十五局集团第五工程有限公司天津300133

平面精密控制网工程已成为高速铁路建设的一个重要组成部分,其精度对后续施工起决定性作用。以某新建高速铁路平面基础控制网复测为例,介绍了复测方案,对外业数据采集、内业数据处理的要求和方法进行实例分析,对平差成果使用坐标较差、... 详细信息

平面精密控制网工程已成为高速铁路建设的一个重要组成部分,其精度对后续施工起决定性作用。以某新建高速铁路平面基础控制网复测为例,介绍了复测方案,对外业数据采集、内业数据处理的要求和方法进行实例分析,对平差成果使用坐标较差、坐标较差相对精度指标进行观测精度评定,测量成果各项指标满足规范相关规定。

关键词：高速铁路平面基础控制网复测精度分析

Construction of amorphous/crystalline heterointerfaces for enhanced electrochemical processes

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eScience 2023年第2期3卷 60-76页

作者： binbin jia Baohong Zhang Zhi Cai Xiuyi Yang Lidong Li Lin Guo Beijing Advanced Innovation Center for Biomedical Engineering Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of EducationSchool of ChemistryBeihang UniversityBeijingChina

Amorphous nanomaterials have emerged as potential candidates for energy storage and conversion owing to their amazing physicochemical *** studies have proved that the manipulation of amorphous nanomaterials can further enhance electrochemical *** date,various feasible strategies have been proposed,of which amorphous/crystalline(a-c)heterointerface engineering is deemed an effective approach to break through the inherent activity limitations of electrode *** following review discusses recent research progress on a-c heterointerfaces for enhanced electrochemical *** general strategies for synthesizing ac heterojunctions are first ***,we highlight various advanced applications of a-c heterointerfaces in the field of electrochemistry,including for supercapacitors,batteries,and *** also elucidate the synergistic mechanism of the crystalline phase and amorphous phase for electrochemical ***,we summarize the challenges,present our personal opinions,and offer a critical perspective on the further development of a-c nanomaterials.

关键词： Nanocomposites Amorphous/crystalline heterogeneous interfaces Synthetic strategy Electrochemical process

核电厂放射性废液环境对设备衬胶耐老化性能的影响

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科技资讯 2024年第4期22卷 186-189页

作者：贾斌斌黄皓张树刚韩健彭舒舒关银柏苏州热工研究院有限公司江苏苏州215004 台山核电合营有限公司广东江门529228

国内某核电厂放射性废液收集、处理、贮存、排放系统容器类设备采用内衬橡胶防腐设计,随着服役时间增长,内衬橡胶层性能会逐渐降低,乃至老化失效,影响设备运行安全,甚至导致放射性液体泄漏。通过橡胶热老化实验,推算对比内衬胶板在辐照... 详细信息

国内某核电厂放射性废液收集、处理、贮存、排放系统容器类设备采用内衬橡胶防腐设计,随着服役时间增长,内衬橡胶层性能会逐渐降低,乃至老化失效,影响设备运行安全,甚至导致放射性液体泄漏。通过橡胶热老化实验,推算对比内衬胶板在辐照、辐照浸渍等不同条件下的使用寿命;通过红外测试、热重测试、冲击强度测试、硬度测试,对比原始胶板、辐照胶板、辐照浸渍胶板等各项理化性能的变化,最终确定核电厂放射性废液环境下橡胶老化的主要影响因素。

关键词：放射性废液辐照橡胶老化性能寿命评估

Rational design of asymmetric atomic Ni-P1N3 active sites for promoting electrochemical CO_(2)reduction

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Nano Research 2023年第2期16卷 2170-2176页

作者： Ming Qu Zhe Chen Zhiyi Sun Danni Zhou Wenjing Xu Hao Tang Hongfei Gu Tuo Liang Pengfei Hu Guangwen Li Yu Wang Zhuo Chen Tao Wang binbin jia Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Beijing 102249China Center of Artificial Photosynthesis for Solar Fuels School of ScienceWestlake UniversityHangzhou 310024China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China School of Chemistry Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 102206China Research Institude of Petroleum Processing Sinopec Group(SINOPEC)Beijing 100083China Shanghai Synchrotron Radiation Facilities Shanghai Institute of Applied PhysicsChinese Academy of ScienceShanghai 201204China

The atomic-level interfacial regulation of single metal sites through heteroatom doping can significantly improve the characteristics of the catalyst and obtain surprising ***,nickel single-site catalysts(SSCs)with dual-coordinated phosphorus and nitrogen atoms were developed and confirmed(denoted as Ni-PxNy,x=1,2 and y=3,2).In CO_(2)reduction reaction(CO_(2)RR),the CO current density on Ni-PxNy was significantly higher than that of Ni-N4 catalyst without phosphorus ***,Ni-P1N3 performed the highest CO Faradaic efficiency(FECO)of 85.0%–98.0%over a wide potential range of−0.65 to−0.95 V(*** reversible hydrogen electrode(RHE)).Experimental and theoretical results revealed that the asymmetric Ni-P1N3 site was beneficial to CO_(2)intermediate adsorption/desorption,thereby accelerating the reaction kinetics and boosting CO_(2)RR *** work provides an effective method for preparing well-defined dual-coordinated SSCs to improve catalytic performance,targetting to CO_(2)RR applications.

关键词： nickel single-site catalysts asymmetric coordination CO_(2)reduction reaction atomic interface

Valence-tailored copper-based nanoparticles for enhanced chemodynamic therapy through prolonged ROS generation and potentiated GSH depletion

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Nano Research 2024年第7期17卷 6342-6352页

作者： Xinyang Li binbin Ding Jing Li Di Han Hao Chen jia Tan Qi Meng Pan Zheng Ping’an Ma Jun Lin State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Chemodynamic therapy(CDT),an inventive approach to cancer treatment,exploits innate chemical processes to trigger cell death through the generation of reactive oxygen species(ROS).While offering advantages over conventional treatments,the optimization of CDT efficacy presents challenges stemming from suboptimal catalytic efficiency and the counteractive ROS scavenging effect of intracellular glutathione(GSH).In this study,we aim to address this dual challenge by delving into the role of copper valence states in *** the unique attributes of copper-based nanoparticles,especially zero-valent copper nanoparticles(CuPd NPs),we aim to enhance the therapeutic potential of *** experiments reveal that zero-valent CuPd NPs outperform divalent copper nanoparticles(Ox-CuPd NPs)by displaying superior catalytic performance and sustaining ROS generation through a dual approach integrating peroxidase-like(POD-like)activity and Cu+***,zero-valent NPs exhibit enhanced GSH depletion compared to their divalent counterparts,thereby intensifying CDT and inducing ferroptosis,ultimately resulting in high-efficiency tumor growth *** findings reveal the impact of valences on CDT,providing novel insights for the optimization and design of CDT agents.

关键词： CuPd nanoparticle ferroptosis chemodynamic therapy valance tailoring tumor therapy

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新疆阿尔泰山东段冰碛物光释光测年研究

地理学报 2018年第5期73卷 957-972页

作者：贾彬彬周亚利赵军陕西师范大学地理科学与旅游学院西安710062 中国人民武装警察部队黄金第八支队乌鲁木齐830057

冰川是塑造地表形态最积极的外营力之一,对冰川地貌的年代学研究是重建古冰川发展史的关键,也是研究气候变化的重要途径。冰碛物是冰川作用的直接产物,代表过去发生的冰川事件,对冰碛物进行准确测年能够为重建古冰川的进退、理解区域古... 详细信息

冰川是塑造地表形态最积极的外营力之一,对冰川地貌的年代学研究是重建古冰川发展史的关键,也是研究气候变化的重要途径。冰碛物是冰川作用的直接产物,代表过去发生的冰川事件,对冰碛物进行准确测年能够为重建古冰川的进退、理解区域古气候变化提供年代学支撑。本文在新疆阿尔泰山东段采集了8个冰碛物样品以进行光释光测年,利用单片再生剂量法对90~125μm的石英颗粒进行等效剂量的测定。通过等效剂量值频率分布特征及De(t)坪区图分析得出大部分冰碛物的光释光信号晒退不彻底,所以利用一阶动力学公式对持续激发的光释光信号晒退曲线(CW-OSL)进行多组分拟合拆分,得到快速、中速、慢速3种组分,依据分离出的快速组分确定等效剂量值。研究结果显示,距今32 ka以来阿尔泰山东段区域在MIS3阶段、MIS2阶段、8.2 ka左右、全新世大暖期及新冰期等5个时段有冰川发育,冰川发育与气候变化密切相关。

关键词：阿尔泰山冰碛物光释光测年冰川作用

Ultraviolet Photodetector based on Sr_(2)Nb_(3)O_(10) Perovskite Nanosheets

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 282-287页

作者：张斌斌 jia Mengmeng LIANG Qi WU Jinsong ZHAI Junyi 李宝文 School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China CAS Center for Excellence in Nanoscience Beijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijin 100083China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Liquid-phase exfoliation was employed to synthesize Sr_(2)Nb_(3)O_(10) perovskite nanosheets with thicknesses down to 1.76 *** electron microscopy(TEM),atomic force microscope(AFM),X-ray photoelectron spectrometer(XPS),and other characterization techniques were used to evaluate the atomic structure and chemical composition of the exfoliated nanosheets.A UV photodetector based on individual Sr_(2)Nb_(3)O_(10) nanosheets was prepared to demonstrate the application of an ultraviolet(UV) *** UV photodetector exhibited outstanding photocurrent and responsivity with a responsivity of 3×10^(5) A·W^(-1) at 5 V bias under 280 nm illumination,a photocurrent of 60 nA,and an on/off ratio of 3×10^(2).

关键词： perovskite nanosheets liquid-phase exfoliation ultraviolet photodetector