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Roles of voltage in semi-insulating GaAs photoconductive semiconductor switch

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Chinese Physics B 2017年第1期26卷 493-497页

作者： hai-juan cui Hong-Chun Yang Jun Xu Yu-Ming Yang Zi-Xian Yang School of Physical Electronics University of Electronic Science and Technology of China Chengdu 610054 China School of Mathematical Sciences University of Electronic Science and Technology of China Chengdu 610054 China

An experimental study of leakage current is presented in a semi-insulating（SI） Ga As photoconductive semiconductor switch（PCSS） with voltages up to 5.8 kV（average field is 19.3 kV/cm）. The leakage current increases nonlinearly with the bias voltage increasing from 1.2×10^-9 A to 3.6×10^-5A. Furthermore, the dark resistance, which is characterized as a function of electric field, does not monotonically decrease with the field but displays several distinct regimes. By eliminating the field-dependent drift velocity, the free-electron density n is extracted from the current, and then the critical field for each region of n（E） characteristic of PCSS is obtained. It must be the electric field that provides the free electron with sufficient energy to activate the carrier in the trapped state via multiple physical mechanisms, such as impurity ionization, fielddependent EL2 capture, and impact ionization of donor centers EL10 and EL2. The critical fields calculated from the activation energy of these physical processes accord well with the experimental results. Moreover, agreement between the fitting curve and experimental data of J（E）, further confirms that the dark-state characteristics are related to these field-dependent processes. The effects of voltage on SI-Ga As PCSS may give us an insight into its physical mechanism.

关键词： photoconductive semiconductor switch leakage current dark resistance nonlinear characteristics

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火灾下预应力混凝土T形截面梁破坏模式研究

中国公路学报 2017年第2期30卷 77-85页

作者：张岗朱美春贺拴海王翠娟长安大学公路学院陕西西安710064 上海师范大学建筑工程学院上海201418 长安大学工程机械学院陕西西安710064

为了给出火灾下预应力混凝土薄腹梁的破坏准则,针对火灾下预应力混凝土T形截面梁桥的破坏问题,研究火灾高温传导模式和热传导混合边界条件,设定预应力混凝土T形截面梁的火灾作用模式,分析其温度场分布状态,并给出预应力混凝土T形截面梁... 详细信息

为了给出火灾下预应力混凝土薄腹梁的破坏准则,针对火灾下预应力混凝土T形截面梁桥的破坏问题,研究火灾高温传导模式和热传导混合边界条件,设定预应力混凝土T形截面梁的火灾作用模式,分析其温度场分布状态,并给出预应力混凝土T形截面梁变形破坏的计算细节和判定条件。采用热力场耦合计算方法,研究不同火灾模式下预应力混凝土T形截面梁桥的破坏模式,跟踪不同火灾模式下预应力混凝土T形截面梁的梁肋变形和翼缘板变形路径。研究结果表明:仅预应力混凝土T形截面梁的梁肋受火时,梁肋的破坏时间和翼缘板的破坏时间相同,其耐火时间相对于其他受火模式较长;预应力混凝土T形截面梁下部单侧受火时,T形截面梁的截面产生显著畸变,受火侧翼缘板的破坏先于梁肋的破坏,破坏时间提前10min;预应力混凝土T形截面梁下部和顶部均受火时,两侧翼缘板的破坏均先于梁肋的破坏,破坏时间提前10min;预应力混凝土T形截面梁顶板受火或整体受火时,T形截面梁的破坏时间相对较早,为40~60min,顶板受火对预应力混凝土T形截面梁的耐火极限影响显著,该研究可为预应力混凝土薄腹梁的抗火性能研究和抗火设计提供理论依据。

关键词：桥梁工程混凝土T形截面梁有限元方法破坏模式预应力火灾

Effect of h-BN rods on high-temperature properties of alumina-carbon refractory

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Journal of Iron and Steel Research International 2025年第1期32卷 115-128页

作者： Ya-ge Li Shuai-bing Wu Feng Liang Zhong Huang Tu Long Long Dong Jun-yi Lv Hong-juan Duan Biao Wen Yong Liu hai-jun Zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Sinosteel Luoyang Institute of Refractories Research Co. Ltd.Luoyang471039HenanChina

h-BN rods modified low-carbon alumina-carbon(Al_(2)O_(3)-C)refractories were prepared,and the effect of h-BN rod addition on the high-temperature properties was investigated and compared with commercial h-BN flake,carbon black,and carbon nanotubes *** results demonstrated that Al_(2)O_(3)-C refractories containing h-BN rods exhibited optimal high-temperature service performances,including 25%higher hot modulus of rupture,21.3%higher thermal shock strength residual ratio,20.9%lower in oxidation and 44.3%less in slag corrosion,compared to the counterpart specimens without ***,benefiting from the synergistic enhancement of the rod-like h-BN and in-situ generated SiC whiskers,the high-temperature service performances of h-BN rods containing specimens outperformed counterpart specimens containing commercial h-BN flake,carbon black,and carbon nanotubes,respectively.

关键词： Al_(2)O_(3)-C refractory h-BN rod Microstructure High-temperature service performance

Enhancing output performance of triboelectric nanogenerator by increasing charge storage capacity of electrodes

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Nano Research 2025年第1期18卷 395-403页

作者： Congcong Hao Zekun Wang Mingzhe Cai Shuaining Cheng Zhongxin Wang Cong Zhai juan cui Yongqiu Zheng Chenyang Xue Key Laboratory of Instrumentation Science and Dynamic Measurement Ministry of Education North University of ChinaTaiyuan 030051China

The practical application of rotating triboelectric nanogenerators is often limited by the wear of high-friction surface materials and low surface charge *** addition to the charge pump replenishment strategy,suppressing charge decay is also crucial for increasing surface charge ***,we present a high performance rotary triboelectric nanogenerator(HPR-TENG)based on a coplanar charge pumping strategy and polyvinyl chloride(PVC)*** has been demonstrated that applying PVC film to the surface of the storage electrode of the main TENG(M-TENG)significantly enhances the M-TENG’s output ***,the HPR-TENG with three layers of PVC film pasted achieved the best output performance,with a peak-topeak output voltage of 2828 V,a peak-to-peak output current of 327μA and a charge transfer of 0.81μC at 500 *** addition,the output improvement effects of different materials are *** TENG with 3 layers of PVC film pasted on it has a maximum output power of 748 mW at a load resistance of 4×10^(6)Ω.HPR-TENG’s output performance remains consistent after 100,000 cycles,which shows excellent *** excellent electrical performance of the HPR-TENG can be used as the energy supply for the tip high-voltage breakdown sensor system,which can achieve 14 breakdowns in 10 *** to its extraordinary electrical performance,HPRTENG can not only serve as an energy supply for cutting-edge high-voltage breakdown sensor systems,but also has the potential to serve as an energy supply for high-pressure sterilization,high-pressure vacuum and water electrolysis.

关键词： triboelectric nanogenerator coplanar charge pump enhancing charge density suppressing charge decay polyvinyl chloride(PVC)film

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数学跨学科主题学习的任务设计原则及流程

教学与管理 2025年第2期 38-42页

作者：郭海娟江苏省海安市实验小学江苏南通226600

在跨学科主题学习中任务承载着学习的主题,是实现预期目标的关键。小学数学跨学科主题学习的任务设计要能让学生以主体身份参与,像专家一样整合多学科要素,在做数学的实践与体验中思考和创造,从而获得不同的解决问题方案;任务的设计包... 详细信息

在跨学科主题学习中任务承载着学习的主题,是实现预期目标的关键。小学数学跨学科主题学习的任务设计要能让学生以主体身份参与,像专家一样整合多学科要素,在做数学的实践与体验中思考和创造,从而获得不同的解决问题方案;任务的设计包括确定核心任务、规划分支任务,创设真实情境、预设驱动问题,设计阶段活动、制定评价方案等关键环节。如此才能帮助学生更好地理解和解决问题,不断提高跨学科主题学习的质量。

关键词：小学数学跨学科主题学习任务设计

大中小学思政课区域一体化的价值意蕴、驱动要素与推进策略

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东北师大学报（哲学社会科学版） 2025年第1期 10-18页

作者：李爱琴师海娟东北林业大学马克思主义学院黑龙江哈尔滨150040

大中小学思政课区域一体化是大中小学思政课一体化的重要组成部分和重点建设方向,其核心要义在于区域教育主体突破学段和校际壁垒,以共同体成员的协作互动促进思想政治教育资源在区域间的有序流动和优化配置,实现大中小学思政课区域一... 详细信息

大中小学思政课区域一体化是大中小学思政课一体化的重要组成部分和重点建设方向,其核心要义在于区域教育主体突破学段和校际壁垒,以共同体成员的协作互动促进思想政治教育资源在区域间的有序流动和优化配置,实现大中小学思政课区域一体化的整体内涵式发展。新时代持续推进大中小学思政课区域一体化走深走实,可广泛凝聚区域多主体人才协同共培的价值共识,形成多模态纵横连贯式的区域教育网络生态系统,全面提升大中小学思想政治教育区域一体化的建设质量。学校思想政治教育政策要求、新时代思政课改革创新发展诉求和学生个人成长发展需求对大中小学思政课区域一体化具有正向驱动作用,牵动着大中小学思政课区域一体化建设的“时”和“序”、“质”和“量”、“道”和“术”。深化大中小学思政课区域一体化建设,要健全常态长效运行机制,畅通区域管理行动经络;补足协同推进短板弱项,统筹区域格局协调发展;建立多元主题合作网络,深化区域合作互联互通;优化教育资源服务供给,实现区域资源无界共享。

关键词：大中小学思政课区域一体化立德树人思想政治教育

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工具病毒载体在针刺镇痛相关脑环路机制研究中的应用

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针刺研究 2025年第1期50卷 116-122页

作者：马翠叶钰娟严兴科甘肃中医药大学针灸推拿学院甘肃兰州730000

针刺镇痛临床疗效确切,但其中枢脑环路机制尚未完全阐明,工具病毒载体技术为针刺镇痛中枢环路机制研究提供了有效手段。本文简述了工具病毒载体的分类及特性,以及近年来工具病毒载体及其携载的功能元件光/化学遗传学技术在疼痛及针刺镇... 详细信息

针刺镇痛临床疗效确切,但其中枢脑环路机制尚未完全阐明,工具病毒载体技术为针刺镇痛中枢环路机制研究提供了有效手段。本文简述了工具病毒载体的分类及特性,以及近年来工具病毒载体及其携载的功能元件光/化学遗传学技术在疼痛及针刺镇痛研究中的应用概况。目前,在针刺镇痛中枢机制研究中,工具病毒结合化学遗传学技术主要用于研究前喙扣带皮层→腹外侧中脑导水管周围灰质(rACC→vlPAG)、前扣带回皮层→丘脑(rACC→Th)及腹外侧中脑导水管周围灰质→海马(vlPAG→HPC)等神经环路机制;工具病毒结合光遗传学技术主要用于研究内侧前额边缘下皮层→伏隔核(IL→NAc)等神经环路。工具病毒及光/化学遗传学技术既可靶向性、精确性地标记特定神经元或神经环路,又能动态、实时监测神经网络功能,为针刺镇痛脑环路机制研究带来了新的实验手段和突破口。

关键词：工具病毒针刺镇痛光遗传学化学遗传学脑环路

Developing a nomogram for postoperative delirium in elderly patients with hip fractures

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World Journal of Psychiatry 2025年第3期15卷 142-155页

作者： Liang Li Wei-Wei Sheng Li-juan Song Shuai Cheng En-Gang cui Yong-Bing Zhang Xue-Zhong Yu Yan-Li Liu Department of Orthopaedics and Traumatology Dongying People’s HospitalDongying 257091Shandong ProvinceChina Department of Health Care Dongying People’s HospitalDongying 257091Shandong ProvinceChina Department of Medical Imaging Dongying People’s HospitalDongying 257091Shandong ProvinceChina Department of Joint Surgery Dongying People’s HospitalDongying 257091Shandong ProvinceChina Department of Spine Surgery Dongying People’s HospitalDongying 257091Shandong ProvinceChina

BACKGROUND Postoperative delirium(POD)is a prevalent complication,particularly in elderly patients with hip fractures(HFs).It significantly affects recovery,length of hospital stay,healthcare costs,and long-term *** studies have investigated risk factors for POD,but most are limited by single-factor analyses or small sample *** study systematically determines independent risk factors using large-scale data and machine learning techniques and develops a validated nomogram model to support early prediction and management of *** To investigate POD incidence in elderly patients with HF and the independent risk factors,according to which a nomogram prediction model was developed and *** This retrospective study included elderly patients with HF who were surgically treated in Dongying People’sHospital from April 2018 to April 2022. The endpoint event includes POD. They were categorized into themodeling and validation cohorts in a 7:3 ratio by randomization. Both cohorts were further classified into thedelirium and normal (non-delirium) groups according to the presence or absence of the endpoint event. Theincidence of POD was calculated, and logistic multivariate analysis was conducted to determine the independentrisk factors. The calibration curve and the Hosmer-Lemeshow test as well as the net benefit threshold probabilityinterval by the decision curve were utilized to statistically validate the accuracy of the nomogram predictionmodel, developed according to each factor’s influence *** study included 532 elderly patients with HF, with an overall POD incidence of 14.85%. The comparison ofbaseline data with perioperative indicators revealed statistical differences in age (P < 0.001), number of comorbidities(P = 0.042), American Society of Anesthesiologists grading (P = 0.004), preoperative red blood cell(RBC) count (P < 0.001), preoperative albumin (P < 0.001), preoperative hemoglobin (P < 0.001), preoperativeplatel

关键词： Hip fracture Postoperative delirium Nomogram Risk factor Retrospective study

线性Markov跳变随机系统的Pareto最优控制

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控制理论与应用 2025年第1期42卷 59-66页

作者：王乐崔凯蒋秀珊赵东亚张维海中国石油大学(华东)新能源学院山东青岛266580 山东科技大学电气与自动化工程学院山东青岛266590

目前针对多个主体、多个目标的带有Markov跳变的线性随机系统的控制问题的研究较少且较为浅显.本文研究了具有乘性噪声的连续时间线性Markov跳变随机系统的Pareto最优控制问题.假设多个主体、多个性能指标由状态和控制变量中的二次部分... 详细信息

目前针对多个主体、多个目标的带有Markov跳变的线性随机系统的控制问题的研究较少且较为浅显.本文研究了具有乘性噪声的连续时间线性Markov跳变随机系统的Pareto最优控制问题.假设多个主体、多个性能指标由状态和控制变量中的二次部分和线性部分的线性组合而形成,证明了Pareto最优与加权和优化之间的关系,从而将多目标优化问题转化为特殊的单目标加权和最优控制问题.基于Pareto博弈理论与广义Itô公式,系统的Pareto有效策略可以通过一组耦合的广义Riccati微分方程与一组耦合的线性微分方程求解,并且可以得到每一个控制器的Pareto解.最后,本文通过数值仿真验证理论结果的有效性.

关键词： Markov跳变随机系统 Pareto控制最优控制系统