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结构简单的并联谐振直流环节型逆变器及其调制策略研究

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中国电机工程学报 2023年第18期43卷 7202-7214页

作者：李思杨明马宇宋天佑徐殿国哈尔滨工业大学电气工程及自动化学院黑龙江省哈尔滨市150001

针对一种新型并联谐振直流环节逆变器的辅助换流电路存在的电流应力高、导通损耗大、元器件数目多等问题,该文提出一种优化改进调制策略,其由3部分组成:基于1型不连续的脉冲宽度调制策略,且以斜率正负交替的锯齿波作为载波,在此二者基... 详细信息

针对一种新型并联谐振直流环节逆变器的辅助换流电路存在的电流应力高、导通损耗大、元器件数目多等问题,该文提出一种优化改进调制策略,其由3部分组成:基于1型不连续的脉冲宽度调制策略,且以斜率正负交替的锯齿波作为载波,在此二者基础上施用分流死区。在所提调制策略下可以对原拓扑的辅助换流电路进行化简,减少一组谐振电路,以降低硬件成本。与原调制策略相比,所提调制策略在不改变辅助换流电路动作频率的前提下,不仅可以实现所有开关器件的软开关动作,而且可以避免辅助换流电路工作过程中产生的谐振电流与负载电流的叠加,从而有效降低辅助换流电路的导通损耗及其内部开关器件的电流应力。文中对所提调制策略的原理进行详细叙述,由此推导简化拓扑的工作模式,并分析其电压/电流应力、元器件数目、参数设计等特性,最后通过一台通用实验样机(SiC MOSFET,5kW/40kHz),对比于原拓扑及原调制策略,以验证所提理论的有效性。

关键词：并联谐振直流环节逆变器辅助换流电路导通损耗电流应力调制策略

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激光引信光束布局方式的选择与分析

红外与激光工程 2006年第6期35卷 700-704页

作者：张正辉杨明许士文哈尔滨工业大学航天学院空间光学工程中心黑龙江哈尔滨150001 天津津航技术物理研究所天津300192

随着光电技术的发展,激光近炸引信已经广泛应用于面空导弹、空空导弹等领域。针对大探测场激光近炸引信在国内外导弹中的实际应用,综合目标特性、目标探测、判别要求、以及工程实践经验,根据实验结果,重点分析了其常用的四种光束布局方... 详细信息

随着光电技术的发展,激光近炸引信已经广泛应用于面空导弹、空空导弹等领域。针对大探测场激光近炸引信在国内外导弹中的实际应用,综合目标特性、目标探测、判别要求、以及工程实践经验,根据实验结果,重点分析了其常用的四种光束布局方式的特点和适用范围,给出了不同光束布局方式的分析、比较方法。研究成果已应用于实际设计中。

关键词：激光近炸引信探测场光束布局导弹

Microbubble-enhanced ultrasound exposure improves gene transfer in vascular endothelial cells

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World Journal of Gastroenterology 2006年第46期12卷 7508-7513页

作者： Fang Nie Hui-Xiong xu Qing Tang ming-De Lu Department of Medical Ultrasonics First Affiliated Hospital Sun Yat-Sen UniversityGuangzhou 510080 Guangdong Province China Department of Hepatobiliary Surgery First Affiliated Hospital Sun Yat-Sen University Guangzhou 510080Guangdong Province China

AIM： To explore the effects of ultrasound exposure combined with microbubble contrast agent （SonoVue） on the permeability of the cellular membrane and on the expression of plasrnid DNA encoding enhanced green fluorescent protein （pEGFP） transfer into human umbilical vein endothelial cells （HUVECs）. METHODS： HUVECs with fluorescein isothiocyanatedextran （FD500） and HUVECs with pEGFP were exposed to continuous wave （1.9 MHz, 80.0 mW/cm^2） for 5 min, with or without a SonoVue. The percentage of FD500 taken by the HUVECs and the transient expression rate of pEGFP in the HUVECs were examined by fluorescence microscopy and flow cytornetry, respectively. RESULTS： The percentage of FDS00-positive HUVECs in the group of ultrasound exposure combined with SonoVue was significantly higher than that of the group of ultrasound exposure alone （24.0%± 5.5% vs 66.6% ± 4.1%, P 〈 0.001）. Compared with the group of ultrasound exposure alone, the transfection expression rate of pEGFP in HUVECs was markedly increased with the addition of SonoVue （16.1% ± 1.9% vs 1.5% ± 0.2%, P 〈 0.001）. No statistical significant difference was observed in the HUVECs survival rates between the ultrasound group with and without the addition of SonoVue （94.1% ± 2.3% vs 91.1% ± 4.1% ）. CONCLUSION： The cell membrane permeability of HUVECs and the transfection efficiency of pEGFP into HUVECs exposed to ultrasound are significantly increased after addition of an ultrasound contrast agent without obvious damage to the survival of HUVECs. This non- invasive gene transfer method may be a useful tool for clinical gene therapy of hepatic tumors.

关键词： Microbubble Ultrasound Gene transfer Human umbilical vein endothelial cell Enhanced green fluorescent protein

Orientation selectivity in cat primary visual cortex: local and global measurement

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Neuroscience Bulletin 2015年第5期31卷 561-571页

作者： Tao xu Hong-Mei Yan xue-Mei Song ming Li Key Laboratory for Neuroinformation of Ministry of Education University of Electronic Science and Technology of China Shanghai Institutes of Biological Sciences Chinese Academy of Sciences The Department of Automatic Control College of Mechatronics and Automation National University of Defense Technology

In this study,we investigated orientation selectivity in cat primary visual cortex（V1） and its relationship with various *** found a strong correlation between circular variance（CV） and orthogonal-topreferred response ratio（O/P ratio）,and a moderate correlation between tuning width and O/P ***,the suppression far from the peak that accounted for the lower CV in cat V1 cells also contributed to the narrowing of the tuning width of *** also studied the dependence of orientation selectivity on the modulation ratio for each cell,which is consistent with robust entrainment of the neuronal response to the phase of the drifting grating *** conclusion,the CV（global measure） and tuning width（local measure） are significantly correlated with the modulation ratio.

关键词： cat orientation selectivity tuning width circular variance primary visual cortex

Selective Hydrogenation of Phenylacetylene by Carbon Monoxide and Water

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CCS Chemistry 2023年第10期5卷 2358-2365页

作者： xuetao Qin Ruiqi Zhang ming xu Yao xu Lirong Zheng Chengyu Li Shixiang Yu Jie Yan Jinglin Xie Genghuang Wu Junfeng Rong Meng Wang Ding Ma College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871 State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029 Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049 Research Institute of Petroleum Processing SINOPECBeijing 100083

Catalytic selective hydrogenation of alkynes to the corresponding alkenes is an important process in industrial *** the selective hydrogenation of alkynes to the alkenes requires ingenuity since alkenes can easily be converted into the corresponding alkanes under reductive *** different reductive reagents to prevent the direct usage of H_(2)can avoid difficulties in hydrogen storage and ***,we demonstrate a tandem process to hydrogenate phenylacetylene by CO and H_(2)Oviathecouplingof thelow-temperaturewater-gas shift reaction and selective hydrogenation of phenylacetylene utilizing theα-MoC *** reductive reagent,CO,not only produces H_(2)from H_(2)O to drive the reaction forward,but it also regulates the selectivity of styrene by preventing further hydrogenation.

关键词： water-gas shift reaction selective hydrogenation of phenylacetylene α-MoC catalyst modulating selectivity by CO

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变频驱动的闭式回路节能型液压升降系统

浙江大学学报（工学版） 2008年第2期42卷 209-214页

作者：胡东明徐兵杨华勇浙江大学流体传动及控制国家重点实验室浙江杭州310027

为进一步降低液压升降系统的装机功率和能耗,提出了一种新式的节能型液压升降系统,其原理是将变转速容积调速、活塞拉缸和蓄能器作液压配重技术结合在一起,构成变频驱动的闭式回路液压系统.研究了该原理在液压电梯中的典型应用,给出了... 详细信息

为进一步降低液压升降系统的装机功率和能耗,提出了一种新式的节能型液压升降系统,其原理是将变转速容积调速、活塞拉缸和蓄能器作液压配重技术结合在一起,构成变频驱动的闭式回路液压系统.研究了该原理在液压电梯中的典型应用,给出了系统装机功率的计算公式,得到了系统装机功率、蓄能器容积与蓄能器工作压力比(最低工作压力与最高工作压力之比)的关系.试验研究了在不同负载工况下电梯轿厢的速度运行性能,并对比分析了该系统与阀控等系统的节能性能.结果表明,采用此新型节能方案不仅能够大幅降低液压电梯系统的装机功率和能耗,使系统平均总效率提高至70%,而且具有良好的速度运行性能.

关键词：液压升降系统液压电梯液压闭式回路变频驱动节能性能

Identification of novel soybean oil content-related genes using QTL-based collinearity analysis from the collective soybean genome

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Journal of Integrative Agriculture 2018年第8期17卷 1727-1735页

作者： xu ming-yue LIU Zhang-xiong QIN Hong-tao QI Hui-dong WANG Zhong-yu MAO Xin-rui XIN Da-wei HU Zhen-bang WU Xiao-xia JIANG Hong-wei QI Zhao-ming CHEN Qing-shan Key Laboratory of Soybean Biology Ministry of Education/College of AgricultureNortheast Agricultural University National Key Facility for Crop Gene Resources and Genetic Improvement(NFCRI)/Key Laboratory of Germplasm Utilization Ministry of Agriculture/Institute of Crop SciencesChinese Academy of Agricultural Sciences

Soybean is a global principal source of edible plant oil. As more soybean oil-related quantitative trait loci(QTLs) have been located in the collective genome, it is urgent to establish a classification system for these distributed QTLs. A collinear platform may be useful to characterize and identify relationships among QTLs as well as aid in novel gene discovery. In this study, the collinearity MCScan X algorithm and collective soybean genomic information were used to construct collinearity blocks, to which soybean oil-related QTLs were mapped. The results demonstrated that 666 collinearity blocks were detected in the soybean genome across 20 chromosomes, and 521 collinearity relationships existed in 231 of the 242 effective soybean oil-related QTLs. This included 214 inclusion relationships and 307 intersecting relationships. Among them, the collinearity among QTLs that are related to soybean oil content was shown on a maximum of seven chromosomes and minimum of one chromosome, with the majority of QTLs having collinearity on two chromosomes. Using overlapping hotspot regions in the soybean oil QTLs with collinearity, we mined for novel oil content-related genes. Overall, we identified 23 putatively functional genes associated with oil content in soybean and annotated them using a number of annotation databases. Our findings provide a valuable framework for elucidating evolutionary relationships between soybean oil-related QTLs and lay a foundation for functional marker-assisted breeding relating to soybean oil content.

关键词： soybean oil QTLs collinearity analysis candidate genes

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应重视甲状旁腺癌的诊治

中华外科杂志 2010年第17期48卷 1281-1284页

作者：徐少明浙江大学医学院附属第二医院普通外科杭州310009

1904年de Quervain首先报告了无功能的甲状旁腺癌（parathyroid carcinoma,PC）,至1933年Sainto等报告了功能性PC以后,人们逐渐对PC有了进一步的认识.PC是甲状旁腺素（PTH）依赖性高钙血症病因之一,其恶性程度差异很大,多数相对较低,但... 详细信息

1904年de Quervain首先报告了无功能的甲状旁腺癌（parathyroid carcinoma,PC）,至1933年Sainto等报告了功能性PC以后,人们逐渐对PC有了进一步的认识.PC是甲状旁腺素（PTH）依赖性高钙血症病因之一,其恶性程度差异很大,多数相对较低,但对人体靶器官损害严重.由于人们认识水平与重视程度不一,PC术前诊断常较困难,治疗常不及时,治疗方法亦常不当,影响疗效.

关键词：甲状旁腺癌 carcinoma 诊治治疗方法甲状旁腺素靶器官损害高钙血症恶性程度

Prevalence of minimal hepatic encephalopathy and quality of life evaluations in hospitalized cirrhotic patients in China

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World Journal of Gastroenterology 2013年第30期19卷 4984-4991页

作者： Ji-Yao Wang Ning-Ping Zhang Bao-Rong Chi Yu-Qing Mi Li-Na Meng Ying-Di Liu Jiang-Bin Wang Hai-Xing Jiang Jin-Hui yang Yun xu Xiao Li Jian-ming xu Guo Zhang Xin-Min Zhou Yu-Zheng Zhuge De-An Tian Jin Ye Yu-Lan Liu Department of Gastroenterology and Hepatology Zhongshan HospitalFudan University Department of Digestive Diseases The First Hospital of Jilin University Department of Hepatology Tianjin Infectious Disease Hospital Department of Digestive Diseases Zhejiang Provincial Hospital of Traditional Chinese Medicine Department of Digestive Diseases Chinese PLA General Hospital(301 Hospital) Department of Digestive Diseases ChinaJapan Union HospitalJilin University Department of Digestive Diseases The First Affiliated Hospital of Guangxi Medical University Department of Hepatology the Second Affiliated Hospital of Kunming Medical College Department of Digestive Diseases the First Affiliated Hospital of Zhengzhou University Department of Digestive Diseases West-China HospitalSichuan University Department of Digestive Diseases the FirstAffiliated Hospital of Anhui Medical University Department of Digestive Diseases the People's Hospital of Guangxi Zhuang Autonomous Region Department of Digestive Diseases Xijing Hospitalthe Fourth Military Medical University Department of Digestive Diseases Nanjing Drum Tower Hospitalthe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008Jiangsu ProvinceChina Tongji Hospital Tongji Medical CollegeHuazhong University of Science and Technology Department of Gastroenterology Union HospitalTongji Medical CollegeHuazhong University of Science and Technology Department of Digestive Diseases Peking University People's Hospital

AIM:To investigate the prevalence of minimal hepatic encephalopathy(MHE)and to assess corresponding health-related quality of life(HRQoL)in hospitalized cirrhotic patients in ***:This multi-center cross-sectional study included 16 teaching hospitals,which were members of "Hepatobiliary Cooperation Group,Society of Gastroenterology,Chinese Medical Association",from different areas of China carried out between June and October in *** the eligible hospitalized cirrhotic patients(n = 538)were required to complete triplicate number connection tests combined with one digit symbol test for diagnosing ***' clinical examination data were complemented by a modified questionnaire assessing *** informed consent was obtained from each ***:Male was predominant(68.6%)in 519 patients who met the criteria of the study,with a mean age of 49.17 ± 11.02 *** most common cause of liver cirrhosis was chronic hepatitis B(55.9%).The prevalence of MHE was 39.9% and varied by ChildPugh-Classification score(CPC-A:24.8%,CPC-B:39.4% and CPC-C:56.1%,P < 0.01).MHE(P < 0.01)and higher CPC scores(P < 0.01)were associated with a high HRQoL scores(reflecting poorer quality of life).The prevalence of MHE was proportionate to CPC(P = 0.01)and high quality of life scores(P = 0.01).CONCLUSION:Hospitalized cirrhotic patients have a high prevalence of MHE that is proportionate to the degree of liver function and HRQoL impairment.

关键词： Minimal hepatic encephalopathy Healthrelated quality of life China Child-Pugh Classification Liver cirrhosis