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Energy and Power Engineering 2013年第4期5卷 1093-1096页

作者： Yan li Longnv li Yongteng Jing fangxu Han Research Institute of Special Electrical Machines Shenyang University of Technology Shenyang China

It is difficult to accurately calculate the short-circuit impedance, due to the complexity of axial dual-low-voltage split-winding transformer winding structure. In this paper, firstly, the leakage magnetic field and short-circuit impedance model of axial dual-low-voltage split-winding transformer is established, and then the 2D and 3D leakage magnetic field are analyzed. Secondly, the short-circuit impedance and split parallel branch current distribution in different working conditions are calculated, which is based on field-circuit coupled method. At last, effectiveness and feasibility of the proposed model is verified by comparison between experiment, analysis and simulation. The results showed that the 3D analysis method is a better approach to calculate the short-circuit impedance, since its analytical value is more closer to the experimental value compared with the 2D analysis results, the finite element method calculation error is less than 2%, while the leakage flux method maximum error is 7.2%.

关键词： Split-winding Transformer Short-circuit Impedance Field-circuit Coupled Current Distribution

Effects of DC Magnetic Bias on the Magnetic and Sound Fields of Transformer

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Energy and Power Engineering 2013年第4期5卷 1097-1100页

作者： Yan li Yanchao Gao Longnv li Di Zhang fangxu Han Research Institute of Special Electrical Machines Shenyang University of Technology Shenyang China

DC bias current flowing into the neutral point of power transformer will seriously affect the normal operation of AC power system. In this paper, exciting current, harmonic component of the excitation current, magnetic flux density and noise of transformer were analyzed when the transformer is in the no-load operation state based on field-circuit coupled method. Through the calculation and analysis, some reference bases are provided for design of transformer.

关键词： DC Magnetic Bias Exciting Current Harmonic Magnetic Flux Density Noise

Synergic effects of Cu_xO electron transfer co-catalyst and valence band edge control over TiO_2 for efficient visible-light photocatalysis

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Chinese Journal of Catalysis 2017年第12期38卷 2120-2131页

作者： lina Kong Xintong Zhang Changhua Wang fangxu Wan Lan li a Institute of Material Physics Key Laboratory for Optoelectronic Materials and Devices of Tianjin Key Laboratory of Display Materials and Photoelectric Devices of Ministry of Education College of Materials Science and Engineering Tianjin University of Technology Tianjin 300191 China Center for Advanced Optoelectronic Functional Materials Research and Key Laboratory of UV‐Emitting Materials and Technology of Ministry of Education Northeast Normal University Changchun 130024 Jilin China

Bandgap engineering by doping and co‐catalyst loading are two primary approaches to designing efficient photocatalysts by promoting visible‐light absorption and charge separation,*** of the TiO2conduction band edge is frequently applied to increase visible‐light absorption but also lowers the reductive properties of photo‐excited ***,we report a visible‐light‐driven photocatalyst based on valance band edge control induced by oxygen excess defects and modification with a CuxO electron transfer co‐*** CuxO grafted oxygen‐rich TiO2microspheres were prepared by ultrasonic spray pyrolysis of the peroxotitanate precursor followed by a wet chemical impregnated *** found that oxygen excess defects in TiO2shifted the valence band maximum upward and improved the visible‐light *** CuxO grafted onto the surface acted as a co‐catalyst that efficiently reduced oxygen molecules to active intermediates(i.e.,O2??radial and H2O2),thus consuming the photo‐generated ***,the CuxO grafted oxygen‐rich TiO2microspheres achieved a photocatalytic activity respectively8.6,13.0and11.0as times high as those of oxygen‐rich TiO2,normal TiO2and CuxO grafted TiO2,for degradation of gaseous acetaldehyde under visible‐light *** results suggest that high visible‐light photocatalytic efficiency can be achieved by combining oxygen excess defects to improve visible‐light absorption together with a CuxO electron transfer co‐*** findings provide a new approach to developing efficient heterojunction photocatalysts.

关键词： Visible light photocatalysis TiO2 CuxO cocatalyst Oxygen‐excess defect Porous microsphere

Extracellular Disintegration of Viral Proteins as an Innovative Strategy for Developing Broad-Spectrum Antivirals Against Coronavirus

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CCS Chemistry 2024年第2期6卷 487-496页

作者： Ke Sun Zhe Ding Xiaoying Jia Haonan Cheng Yingwen li Yan Wu Zhuoyu li Xiaohua Huang fangxu Pu Entao li Guiyou Wang Wei Wang Yun Ding Gary Wong Sandra Chiu Jiaming Lan Aiguo Hu Shanghai Key Laboratory of Advanced Polymeric Materials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237 CAS Key Laboratory of Molecular Virology&Immunology Chinese Academy of SciencesShanghai 200031 University of the Chinese Academy of Sciences Beijing 100049 State Key Laboratory of Virology Center for Biosafety Mega-ScienceWuhan Institute of VirologyChinese Academy of SciencesWuhan 430071 Division of life Sciences and Medicine University of Science and Technology of ChinaHefeiAnhui 230027 Department of Clinical Laboratory The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230001

The coronavirus disease 2019(COVID-19)pandemic,caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has claimedmillions of lives and caused innumerable economic losses ***,state-of-the-art treatments still lag behind the continual emergence of new *** to resolving this issue is developing antivirals to deactivate coronaviruses regardless of their structural ***,we report an innovative antiviral strategy involving extracellular disintegration of viral proteins with hyperanion-grafted enediyne(EDY)*** core EDY generates reactive radical species and causes significant damage to the spike protein of coronavirus,while the hyperanion groups ensure negligible cytotoxicity of the *** EDYs exhibit antiviral activity down to nanomolar concentrations,and the selectivity index of up to 20,000 against four kinds of human coronavirus,including the SARS-CoV-2 Omicron variant,suggesting the high potential of this new strategy in combating the COVID-19 pandemic and a future“disease X.”

关键词： enediyne broad spectrum antiviral protein disintegration coronavirus polyanions

基于真实世界研究探析纯中药“序贯三法”对252例2型糖尿病患者胰岛功能的影响

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中华中医药学刊 2021年第10期39卷 253-258页

作者：庞国明张芳李鹏辉姚沛雨马宇鹏朱璞武楠平佳宜鲍玉晓王志强付永祥李方旭王银姗娄静翟纪功高言歌陈丹丹孔丽丽曹秋平叶乃菁南凤尾陈杰郑文静王凯锋开封市中医院河南开封475000 北京中医药大学深圳医院(龙岗) 广东深圳518000 四川省第二中医院四川成都610000 扬州市中医院江苏扬州225000 镇江市中医院江苏镇江212000

目的基于真实世界研究探析纯中药治疗2型糖尿病(T2DM)的临床疗效及对胰岛功能的影响。方法收集自2018年8月—2020年8月间来自5家医疗机构的T2DM患者252例,采用纯中药"序贯三法"治疗,12周为1疗程,观察治疗前后空腹血糖(FBG)、餐后2 h血糖... 详细信息

目的基于真实世界研究探析纯中药治疗2型糖尿病(T2DM)的临床疗效及对胰岛功能的影响。方法收集自2018年8月—2020年8月间来自5家医疗机构的T2DM患者252例,采用纯中药"序贯三法"治疗,12周为1疗程,观察治疗前后空腹血糖(FBG)、餐后2 h血糖(2hPG)、空腹及餐后1 h、2 h、3 h胰岛素水平,空腹及餐后1 h、2 h、3 h胰高血糖素水平,胰岛β细胞功能(HOMA-βF)水平改善情况。结果本研究受试者252例,治疗后空腹血糖(FBG)、餐后2 h血糖(2hPG)均显著下降,差异具有统计学意义(P0.05);空腹及餐后1 h、2 h、3 h胰高血糖素水平较治疗前明显下降,差异具有统计学意义(P<0.01);胰岛β细胞功能(HOMA-βF)较治疗前明显上升,差异具有统计学意义(P<0.01)。结论纯中药"序贯三法"治疗T2DM临床疗效确切,能有效降低血糖、改善胰岛素分泌,降低胰岛素抵抗,降低胰高血糖素,改善患者胰岛功能,疗效确切,值得临床推广。

关键词：真实世界研究 2型糖尿病纯中药治疗序贯三法胰岛功能

Gynecologic infections seen in ThinPrep cytological test in Wuhan, China

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Frontiers of Medicine 2014年第2期8卷 236-240页

作者： Hang Zhou Yao Jia Jian Shen Shaoshuai Wang Xiong li Ru Yang Kecheng Huang Ting Hu fangxu Tang Jin Zhou Jingping Yuan Lei Huang Xun Tian Zhilan Chen Qinghua Zhang Changyu Wang ling Xi Dongrui Deng Hui Wang Ding Ma Shuang li Cancer Biology Research Center Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China Department of Obstetrics and Gynecology Nanjing Drum Tower Hospital Nanjing University Medical School Nanjing 210008 China Department of Gynecology and Obstetrics the Central Hospital of Wuhan Wuhan 430014 China

This study aimed to analyze the prevalence of bacterial, Candida, Trichomonas, and human papillomavirus （HPV） infections in ThinPrep cytological test （TCT） performed on women of Wuhan, China. ThinPrep smears were screened by two independent experienced pathologists and reported from 2008 to 2010. A total of 46 866 ThinPrep smears were studied, and smears with inflammation were analyzed. Of the 44 162 enrolled patients, inflammation changes were observed in 21 935 （49.7%） and specific infections in 6884 （31.4%）. The infections detected were as follows： bacteria, 5663 （82.3%）; Candida, 825 （12.0%）; Trichomonas, 273 （4.0%）; and HPV, 148 （2.1%）. Significant changes were found in the prevalence of bacteria and Candida among women who underwent TCT before and after 2010. Z2 revealed an increasing proportion of specific infections found in smears after 2010 （P = 0.000）. In conclusion, bacterial infection was the most detectable in the ThinPrep smears, followed by Candida and Trichomonas. The prevalence of infection identified by TCT was found to be similar in previous literature in China.

关键词： ThinPrep cytological test human papillomavirus Candida infection Trichomonas infection bacterial infection

轴向双分裂发电机变压器漏磁场及穿越短路阻抗计算与分析

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高电压技术 2014年第6期40卷 1623-1629页

作者：李岩李龙女井永腾韩芳旭沈阳工业大学特种电机研究所沈阳110870 特变电工沈阳变压器集团有限公司沈阳110025

由于轴向双分裂发电机变压器绕组结构复杂,其短路阻抗较难准确地计算。为此,以1台轴向双分裂发电机变压器为例,建立了漏磁场和等效电路模型,对其进行了3维和2维漏磁场分析。并采用漏磁链法和场路耦合方法进一步计算了不同工况下的穿越... 详细信息

由于轴向双分裂发电机变压器绕组结构复杂,其短路阻抗较难准确地计算。为此,以1台轴向双分裂发电机变压器为例,建立了漏磁场和等效电路模型,对其进行了3维和2维漏磁场分析。并采用漏磁链法和场路耦合方法进一步计算了不同工况下的穿越短路阻抗以及分裂支路电流分配问题,将计算结果与实验值进行对比分析。结果表明:对于短路阻抗的计算,采用场路耦合的3维有限元法比2维有限元法及漏磁链法更接近实验值,3维有限元法计算误差<2%,而漏磁链法最大误差达到了7.2%;与漏磁链法相比,3维有限元法能够更精确地计算变压器的漏磁场以及分裂支路电流分配问题。对分裂变压器短路阻抗的计算研究为分裂变压器的合理设计提供了参考依据。

关键词：分裂式变压器短路阻抗场路耦合有限元法漏磁场电流分配

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超高压变压器铁芯硅钢片磁致伸缩力数值计算

高电压技术 2017年第3期43卷 980-986页

作者：韩芳旭李岩井永腾王欢沈阳工业大学特种电机研究所沈阳110870 特变电工沈阳变压器集团有限公司沈阳110144

超高压电力变压器本体振动噪声主要来源于铁芯磁致伸缩,为了准确计算变压器铁芯磁致伸缩效应,提出了基于磁致伸缩力–热应力比拟的数值计算方法。首先采用ANSYS有限元分析软件建立电力变压器3维瞬态电磁场数值计算分析模型,通过求解提... 详细信息

超高压电力变压器本体振动噪声主要来源于铁芯磁致伸缩,为了准确计算变压器铁芯磁致伸缩效应,提出了基于磁致伸缩力–热应力比拟的数值计算方法。首先采用ANSYS有限元分析软件建立电力变压器3维瞬态电磁场数值计算分析模型,通过求解提取铁芯每个节点不同时刻的的磁密值;其次根据磁致伸缩力–热应力的比拟,加载试验测得的硅钢片磁致伸缩特性曲线,计算得到铁芯不同时刻各个节点的磁致伸缩力;然后将铁芯磁致伸缩力导入到结构场和声场计算模型中,求得铁芯本体的振动位移及其声压分布;最后对通过减小磁密来降低铁芯本体振动噪声的效果进行了分析,并对比了不同磁密下铁芯本体振动噪声的强度与分布,证明了该方法的有效性,对比结果表明铁芯磁密降低0.05 T,其声压最大值降低约1.26 d B。

关键词：超高压变压器铁芯磁致伸缩热应力比拟振动噪声

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超高压双器身结构的变压器设计与电磁分析

高电压技术 2016年第7期42卷 2322-2328页

作者：李洪奎井永腾李岩李龙女韩芳旭沈阳理工大学自动化与电气工程学院沈阳110159 沈阳工业大学电气工程学院沈阳110870

由于超高压变压器采用独立调压结构(分为主体变压器和调压变压器),此结构变压器占地面积大,安装、调试和维修工作复杂。因此,提出一种新型器身结构,为双器身共箱式结构,即主体变压器和调压变压器设计在同一油箱内,可使占地面积大大减小... 详细信息

由于超高压变压器采用独立调压结构(分为主体变压器和调压变压器),此结构变压器占地面积大,安装、调试和维修工作复杂。因此,提出一种新型器身结构,为双器身共箱式结构,即主体变压器和调压变压器设计在同一油箱内,可使占地面积大大减小,并降低了安装、调试和维修工作的难度。首先利用三维有限元分析方法,结合超高压双器身变压器的磁路特点,建立"磁场-电路"耦合数学模型,计算分析该产品漏磁场,并对金属结构件磁密、损耗进行计算和分析。同时,采用能量法对产品短路阻抗进行求解,最后通过实验值定量地分析此结构对短路阻抗的影响。结果表明:采用调压变压器新结构后,油箱磁密幅值降低了0.01 T;夹件磁密幅值降低了4.16%;夹件损耗降低了8.1%,短路阻抗略有增加,增加的最大幅值为2.56%,并通过与实验数据的对比得到计算误差<2%,验证了计算的有效性。通过计算与分析表明,新结构与原结构的产品特性变化不大,新结构符合生产技术要求。

关键词：超高压变压器双器身漏磁场短路阻抗电磁分析

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跨介质航行器高速入水冲击载荷特性

兵工学报 2021年第7期42卷 1440-1449页

作者：袁绪龙栗敏丁旭拓任伟周方旭西北工业大学航海学院陕西西安710072

跨介质航行器组合了导弹与超空泡武器的优势,比导弹的末段突防能力强,同时弥补了超空泡武器航程不足的缺点,是未来反舰武器的重要发展方向。跨介质航行器高速入水冲击载荷特性及其降载方法是跨介质航行器研发中的关键技术之一。建立跨... 详细信息

跨介质航行器组合了导弹与超空泡武器的优势,比导弹的末段突防能力强,同时弥补了超空泡武器航程不足的缺点,是未来反舰武器的重要发展方向。跨介质航行器高速入水冲击载荷特性及其降载方法是跨介质航行器研发中的关键技术之一。建立跨介质航行器高速入水多相流场与弹道耦合仿真模型,进行模型验证与校核。对典型工况下的跨介质航行器高速入水过程冲击载荷特性进行仿真,并对不同速度下的高速入水过程弹道参数进行对比。结果表明:预置舵角引起的尾拍运动产生周期性的法向过载,达到轴向过载的2.7倍左右;法向力主要由振荡攻角引起的位置力构成,惯性力很小,可以忽略;入水速度的增大引起尾拍频率加快,攻角振荡幅度降低,入水速度对法向冲击力系数影响很小。

关键词：跨介质航行器高速入水冲击载荷尾拍运动仿真建模