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整流侧控制方式对特高压直流输电系统换相失败影响研究

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中国电力 2015年第7期48卷 1-7页

作者：陈仕龙荣俊香毕贵红李兴旺曹蕊蕊昆明理工大学电力工程学院云南昆明650500

特高压直流输电系统发生换相失败时,会引起直流电压和直流电流突变,严重影响直流系统的安全稳定运行。控制系统是特高压直流输电系统的核心部分,其控制方式对系统的输出响应有重要影响。分析特高压直流输电系统换相失败的原因,介绍整流... 详细信息

特高压直流输电系统发生换相失败时,会引起直流电压和直流电流突变,严重影响直流系统的安全稳定运行。控制系统是特高压直流输电系统的核心部分,其控制方式对系统的输出响应有重要影响。分析特高压直流输电系统换相失败的原因,介绍整流侧的控制方式,建立了云广特高压直流输电系统仿真模型,研究云广特高压直流输电系统整流侧采用定电流控制方式和定功率控制方式对换相失败的影响。仿真结果表明:当逆变侧换流变压器变比K改变时,整流侧采用定电流控制与采用定功率控制相比,系统发生换相失败时的临界变比较大;当逆变侧交流母线发生三相对称接地故障、两相短路故障及单相接地故障时,整流侧采用定电流控制与定功率控制相比,系统不发生连续换相失败的临界电阻较小。整流侧采用定电流控制方式时,对换相失败的控制能力优于定功率控制方式。

关键词：特高压直流换相失败定电流控制定功率控制

低氧和运动干预对肥胖小鼠心肌组织Ghrelin-GHSR通路及相关蛋白的影响

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中国运动医学杂志 2023年第6期42卷 460-469页

作者：王腾生付鹏宇朱镕鑫于晶晶郜瑞睿龚丽景北京体育大学运动与体质健康教育部重点实验室北京100084 西北工业大学体育部陕西西安710072 上海体育科学研究所上海2000302 北京体育大学运动人体科学学院北京100084 北京体育大学中国运动与健康研究院北京100084

目的:探究低氧和运动干预改善肥胖小鼠心肌损伤程度和对胃饥饿素-生长激素促分泌激素受体(Ghrelin-GHSR)通路及相关蛋白的影响。方法:50只雄性C57BL/6J小鼠随机分为普通对照组(N组,n=8,饲喂普通饲料)和高脂膳食组(H组,n=42,饲喂高脂饲料... 详细信息

目的:探究低氧和运动干预改善肥胖小鼠心肌损伤程度和对胃饥饿素-生长激素促分泌激素受体(Ghrelin-GHSR)通路及相关蛋白的影响。方法:50只雄性C57BL/6J小鼠随机分为普通对照组(N组,n=8,饲喂普通饲料)和高脂膳食组(H组,n=42,饲喂高脂饲料8周以建立肥胖模型)。将建模成功后的肥胖小鼠随机分为肥胖对照组(HN组,n=7)、肥胖常氧运动组(HE组,n=7)、肥胖低氧暴露组(HHN组,n=8)和肥胖低氧运动组(HHE组,n=7)。HE和HHE组进行1 h/次/天、速度12 m/min的跑台训练;HHN和HHE组进行11.2%O_(2)暴露,8 h/次/天,6次/周。4周后,测试血糖血脂水平;HE染色观察心肌组织形态,免疫组化染色观察Ghrelin蛋白水平和分布;RT-PCR和Western blotting法分别检测心肌组织中Ghrelin、GHSR-1a、Ghrelin O-酰基转移酶(GOAT)、心肌肌钙蛋白I3基因(TNNI3)、神经肽Y1R(NPY1R)、血管内皮生长因子A(VEGFA)mRNA和蛋白的表达。结果:(1)HE和HHN组体重较HN组显著降低(P<0.05);HN组血糖(GLU)、甘油三酯(TG)、总胆固醇(TC)、游离脂肪酸(FFA)和低密度脂蛋白胆固醇(LDL-C)水平显著高于N组,高密度脂蛋白胆固醇(HDL-C)水平显著低于N组(P<0.05);HE和HHN组GLU水平显著低于HN组,HHN组TC水平显著低于HN组(P<0.05);HHE组GLU和TC水平显著低于HE组,LDL-C水平显著低于HN组(P<0.05);HE、HHN和HHE三组FFA水平显著低于HN组,HDL-C水平显著高于HN组(P<0.05)。(2)HN组较N组出现心肌细胞肥大和心肌纤维形态改变及强嗜酸性染色,损伤评分显著升高(P<0.05);HHE组心肌形态明显改善,且损伤评分显著低于HN组和HE组(P<0.05);HHN组损伤评分高于HE组(P<0.05);HHE组Ghrelin在心肌组织中表达量显著高于HN组(P<0.05)。(3)HN组心肌Ghrelin和GHSR-1a mRNA表达水平较N组显著降低(P<0.05);HE组Ghrelin、GHSR-1a、GOAT和VEGFA mRNA水平显著高于HN组(P<0.05);HE组TNNI3 mRNA表达水平显著低于HN组(P<0.05);HHE组Ghrelin、GHSR-1a和VEGFA mRNA表达水平分别显著高于HHN和HE组,TNNI3和NPY1R mRNA水平分别显著低于HHN组和HE组(P<0.05)。(4)HN组心肌Ghrelin和VEGFA蛋白表达量显著低于N组,NPY1R和TNNI3显著高于N组(P<0.05);HE组Ghrelin、GHSR-1a和VEGFA蛋白水平显著高于HN组(P<0.05);HE组和HE组TNNI3表达量显著低于HN组(P<0.05);HE组Ghrelin、GOAT和VEGFA蛋白表达量分别显著高于HHN组和HE组,NPY1R蛋白表达量显著低于HE组(P<0.05)。(5)肥胖小鼠心肌Ghrelin和VEGFA蛋白水平分别受运动和运动×低氧影响,GHSR-1蛋白水平受运动影响,GOAT和NPY1R蛋白水平受运动×低氧的影响,TNNI3蛋白水平分别受运动和低氧影响(P<0.05)。结论:低氧和运动干预可改善肥胖小鼠的心肌形态及减轻其心肌损伤程度,可能机制之一是低氧和运动干预上调心肌组织Ghrelin-GHSR信号通路相关基因和蛋白的表达。

关键词：低氧运动肥胖心肌组织 Ghrelin

Cross section measurement for the^(232)Th(n,f)reaction in the 4.50−5.40 MeV region using a time projection chamber

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Chinese Physics C 2024年第10期48卷 157-167页

作者： Haofan Bai Han Yi Yankun Sun Yiwei Hu Jie Liu Zepeng Wu Cong Xia Wenkai Ren Wentian cao Tieshuan Fan Guohui Zhang ruirui Fan Yang Li Wei Jiang Yonghao Chen You Lv Changjun Ning Weihua Jia Zhiyong Zhang Haolei Chen Zhen Chen Maoyuan Zhao Changqing Feng Shubin Liu State Key Laboratory of Nuclear Physics and Technology Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China National Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear TechnologyXi'an 710024China Department of Nuclear Science and Technology School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China

Accurate cross sections of neutron induced fission reactions are required in the design of advanced nuclear systems and the development of fission *** projection chambers(TPCs),with their track reconstruction and particle identification capabilities,are considered the best detectors for high-precision fission cross section *** TPC developed by the back-streaming white neutron source(Back-n)team of the China Spallation Neutron Source(CSNS)was used as the fission fragment detector in *** this study,the cross sections of the ^(232)Th(n,f)reaction at five neutron energies in the 4.50−5.40 MeV region were *** fission fragments and α particles were well identified using our TPC,which led to a higher detection efficiency of the fission fragments and smaller uncertainty of the measured cross *** is the first measurement of the ^(232)Th(n,f)reaction using a TPC for the detection of fission *** uncertainties less than 5%,our cross sections are consistent with the data in different evaluation libraries,including JENDL-4.0,ROSFOND-2010,CENDL-3.2,ENDF/B-VⅢ.0,and BROND-3.1,whose uncertainties can be reduced after future improvement of the measurement.

关键词： ^(232)Th(n,f)fission cross section time projection chamber(TPC) ^(232)Th

In situ decomposition of metal-organic frameworks into ultrathin nanosheets for the oxygen evolution reaction

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Nano Research 2016年第6期9卷 1856-1865页

作者： Kai He Zhen cao ruirui Liu Ya Miao Yi Ding Key Laboratory of Colloid and Interface Chemistry of State Education Ministry School of Chemistry and Chemical Engineering Shandong University Jinan 250100 China Tianjin Key Laboratory of Advanced Functional Porous Materials School of Materials Science and Engineering Tianjin University of Technology Tianjin 300384 China

The oxygen evolution reaction （OER） is a pivotal process for water-splitting and many other energy technologies involving oxygen electrodes. Herein, a new synthesis strategy is proposed to prepare OER catalysts based on a simple yet flexible in situ decomposition of Co-based acetate hydroxide metal-organic frameworks （MOFs）. This process allows straightforward fabrication of various 2D hydroxide ultrathin nanosheets （UNSs） with excellent component controllability. The as-obtained Co-based hydroxide UNSs demonstrate superior catalytic activity for the OER due to the exposure of numerous active sites. In particular, the CoNi hydroxide UNSs exhibit low overpotentials （r/） of 324 and 372 mV at current densities of 10 and 100 mA-cm-2, respectively; a large turnover frequency （TOF） of 0.16 s-~ at T/= 380 mV; and a small Tafel slope of 33 ***-~ in an alkaline environment. Importantly, these values are superior to those of the state-of-the- art IrO2 commercial electrocatalyst. This facile strategy enables the exploration of more efficient and economic OER electrocatalysts with various constituents and opens a promising avenue for large-scale fabrication of functional nanocatalysts for use in clean ener~：v technologies.

关键词： oxygen evolution reaction metal-organic frameworks(MOFs) in situ decomposition ultrathin nanosheets electrocatalyst

Effects of stochastic food deprivation on energy budget,body mass and activity in Swiss mice

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Current Zoology 2009年第4期55卷 249-257页

作者： Zhijun ZHAO Jing cao Ye TIAN ruirui WANG Guiying WANG School of Agricultural Science Liaocheng University Liaocheng Shandong 252059 China

When small animals are faced with an unpredictable food supply,they can adapt by altering different components of their energy budget such as energy intake,metabolic rate,rate of non-shivering thermogenesis(NST)or *** present study examined the effect of stochastic food deprivation(FD)on body mass,food intake,resting metabolic rate(RMR),NST and behaviour in male Swiss *** a period of 4 weeks' FD,animals were fed ad libitum for a randomly assigned 4 days each week,but were deprived of food for the other 3 *** results showed that body mass significantly dropped on FD days compared to *** intake of FD mice increased significantly on ad libitum days,ensuring cumulative food intake,final body mass,fat mass,RMR and NST did not differ significantly from ***,gastrointestinal tract mass increased in FD mice,but digestibility *** general,activity was higher on deprived days,and feeding behaviour was higher on ad libitum days suggesting that Swiss mice are able to compensate for stochastic FD primarily by increasing food intake on ad libitum days,and not by reducing energy expenditure related to RMR or NST.

关键词： Behaviour Body mass Food availability Food intake Swiss mice

合并微血管侵犯的HCC患者术后辅助治疗:现状与前景

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保健医学研究与实践 2024年第1期21卷 150-156页

作者：黄俊杰黄平廖锐孙锐睿曹洪祥重庆医科大学第一临床学院重庆400016 重庆医科大学附属第一医院肝胆外科重庆400016

原发性肝细胞肝癌是世界上常见的恶性肿瘤,手术切除是其首选的治疗方式,但微血管侵犯(MVI)作为其独立的危险因素影响着手术后患者的生存情况。本文介绍了术后MVI阳性对患者预后的影响,同时介绍了目前常用于预防术后复发,改善肝切除患者... 详细信息

原发性肝细胞肝癌是世界上常见的恶性肿瘤,手术切除是其首选的治疗方式,但微血管侵犯(MVI)作为其独立的危险因素影响着手术后患者的生存情况。本文介绍了术后MVI阳性对患者预后的影响,同时介绍了目前常用于预防术后复发,改善肝切除患者生存情况的一系列辅助治疗方法,包括放射疗法、肝动脉化疗栓塞术(TACE)、肝动脉灌注化疗(HAIC)、靶向疗法、免疫疗法、抗病毒及营养支持疗法,评述了各类疗法对MVI阳性患者的治疗效果。作者认为,大多数治疗均展现了相应的应用前景,但疗效和适用人群有待进一步探索,而联合治疗可能是未来术后辅助治疗前进的方向。

关键词：原发性肝癌微血管侵犯肿瘤复发术后辅助治疗

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整体式自航浮体水动力性能数值研究

船舶 2024年第4期35卷 29-37页

作者：张瑞瑞严亮张曙光曹稼秀江苏科技大学船舶与海洋工程学院镇江212003 中国人民解放军92228部队北京102488

发生海难时,船舶配备的救生浮体就位速度对救援效率和成功率起着很大的作用,而救生浮体在波浪中的水动力性能对其就位速度又有着至关重要的影响。该文针对自主研发的整体式自航浮体,从提高速度角度出发,采用数值方法研究浮体以不同尾倾... 详细信息

发生海难时,船舶配备的救生浮体就位速度对救援效率和成功率起着很大的作用,而救生浮体在波浪中的水动力性能对其就位速度又有着至关重要的影响。该文针对自主研发的整体式自航浮体,从提高速度角度出发,采用数值方法研究浮体以不同尾倾角度和航速在静水和规则波中航行的水动力学性能。研究结果发现:自航浮体在静水和规则波中受到的阻力随航行速度增加近乎呈线性增大,且在规则波中受到的阻力普遍大于静水中的。自航浮体的高压区增大、低压区的出现以及波浪作用浮体周围高低压区交替出现,会进一步引起浮体的运动响应。自航浮体的运动响应受吃水影响大,初始吃水较小或较大时,浮体的纵摇运动更加明显,而自航浮体的垂荡运动是随着吃水增大而愈发显著。研究结论可为自航浮体的研发提供必要的数据支撑。

关键词：力学特性流场特性运动响应规则波计算流体力学(CFD)

Dynamic recrystallization-induced temperature insensitivity of yield stress in single-crystal Al1.2CrFeCoNi micropillars

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Science China(Technological Sciences) 2021年第1期64卷 11-22页

作者： HUANG ruirui ZHANG Qian ZHANG Xuan LI JianGuo cao TangQing YAO JiaHao XUE YunFei GAO HuaJian LI XiaoYan Center for Advanced Mechanics and Materials Applied Mechanics LaboratoryDepartment of Engineering MechanicsTsinghua UniversityBeijing 100084China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Mechanical and Aerospace Engineering College of EngineeringNanyang Technological UniversitySingapore 639798Singapore Institute of High Performance Computing A*STARSingapore 138632Singapore

High-entropy alloys, a new class of metallic materials, exhibit excellent mechanical properties at high temperatures. In spite of the worldwide interest, the underlying mechanisms for temperature dependence of mechanical properties of these alloys remain poorly understood. Here, we systemically investigate the mechanical behaviors and properties of Al_(1.2)CrFeCoNi(comprising a body-centered cubic phase) and Al_(0.3)CrFeCoNi(comprising a face-centered cubic phase) single-crystal micropillars with three orientations([100], [110], and [111]) at temperatures varying from 300 to 675 K by using in situ compression of micropillars inside a scanning electron microscope. The results show that the yield stresses of Al_(1.2)CrFeCoNi micropillars are insensitive to temperature changes, and their flow stresses and work hardening rates increase slightly with increasing temperature from 300 to550 K, which differs from the typical temperature dependence of yield/flow stresses in metals and alloys. In contrast,Al_(0.3)CrFeCoNi micropillars exhibit typical thermal softening. Furthermore, it is found that the Al_(1.2)CrFeCoNi micropillars exhibit a transition from homogenous deformation to localized deformation at a critical temperature, while the Al_(0.3)CrFeCoNi micropillars always maintain a well-distributed and fine slip deformation. Detailed transmission electron microscopy analyses reveal that dynamic recrystallization(involving dislocation tangles, and formation of dislocation cell structures and sub-grains)plays a key role in the observed temperature insensitivity of the yield stress and increasing flow stress(and work hardening rate)with increasing temperature in the Al_(1.2)CrFeCoNi micropillars, and that thermally activated dislocation slip leads to thermal softening of the Al_(0.3)CrFeCoNi micropillars. The differences in deformation modes and temperature dependence of the mechanical properties between Al_(1.2)CrFeCoNi and Al_(0.3)CrFeCoNi essentially originate from the d

关键词： high entropy alloy temperature insensitivity dynamic recrystallization micropillar deformation twin

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石首鱼药用的本草考证

今日药学 2024年第7期34卷 555-560页

作者：张睿蕊姚英吴科锋吴孟华曹晖国家中药现代化工程技术研究中心广东珠海519000 珠海市丽珠中药现代化科技有限公司广东珠海519000 暨南大学药学院/暨南大学岭南传统中药研究中心广东广州510632 国家中药现代化工程技术研究中心岭南资源分中心广东广州510632 广东医科大学海洋医药研究院广东湛江524023 国家中药现代化工程技术研究中心海洋中药分中心广东湛江524023

自古以来,石首鱼既是我国重要的经济鱼类,又是珍贵的海洋中药来源。本研究通过系统查阅历代本草及各地方志,结合现代文献、权威鱼类书籍进行综合分析,对石首鱼的名称以及各部位入药的历史记载进行梳理与考证,为明确石首鱼的药用价值提... 详细信息

自古以来,石首鱼既是我国重要的经济鱼类,又是珍贵的海洋中药来源。本研究通过系统查阅历代本草及各地方志,结合现代文献、权威鱼类书籍进行综合分析,对石首鱼的名称以及各部位入药的历史记载进行梳理与考证,为明确石首鱼的药用价值提供历史依据。经考证,石首鱼的别名众多,主要与其外观、渔汛等相关。石首鱼的肉、鱼耳石、鱼鳔、鱼鳞等均有入药的记载,在内科、皮肤科、耳鼻喉科及泌尿科均见使用。本研究的考证结果厘清了我国习见石首鱼的品名及各部位的药用功效等历史脉络,可为石首鱼药用资源的开发利用提供文献支持。

关键词：石首鱼大黄鱼小黄鱼鱼肉本草考证