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High performance perovskite solar cells using TiO2 nanospindles as ultrathin mesoporous layer

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Journal of Energy Chemistry 2018年第4期27卷 951-956页

作者： Yinhua Lv Bing Cai yihui Wu Shubo Wang Qike jiang Qingshan Ma Jingyue(Jimmy)Liu Wen-Hua Zhang Dalian National Laboratory for Clean Energy.Dalian Institute of Chemical Physics Chinese Academy of Sciences.Dalian 116023LiaoningChina University of Chinese Academy of Sciences No.19(A)Yuquan Road.Shijingshan DistrictBeijing 100049.China Sichuan Research Center of New Materials Institute of Chemical MaterialsChina Academy of Engineering PhysicsChengdu 610200.Sichuan.China jiangsu Collaborative Innovation Center of Photovoltuic Science an Engineering.Changzhou University Changzhou 213164JiangsuChina Department of Physics Arizona State UniversityTempeArizona 85287.USA

Single crystal anatase TiO2 nanospindles （NSs） with highly exposed {101} facets were synthesized and employed as electron transport materials （ETMs） in perovskite solar cells （PSCs）. Time-resolved photoluminescence （TRPL） spectra revealed that the TiO2 NSs are more effective than TiO2 nanoparticles in accepting electrons from perovskite. Moreover. the TiO2 nanospindles further endowed the PSCs with good reproducibility and suppressed hysteresis. The best device with TiO2 NSs as ETMs yielded power conversion efficiency （PCE） of 19.6%, demonstrating that the home-made TiO2 NSs is a good ETM for PSCs.

关键词： Electron transport material Perovskite solar cell TiO2 nanospindles Ultrathin mesoporous layer

Bottleneck Analysis of the Minimum Cost Problem for the Generalized Network Based on Augmented Forest Structure

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Chinese Journal of Chemical Engineering 2003年第1期11卷 62-67页

作者：江永亨王军金以慧 Departmentof Automation Tsinghua University

The bottleneck analysis of the minimum cost problem for the generalized network (MCPGN) is discussed. The analysis is based on the network simplex algorithm, which gains negative cost graphs by constructing augmented forest structure, then augments flows on the negative cost graphs until the optimal revolution is gained. Bottleneck structure is presented after analyzing the augmented forest structure. The negative cost augmented graphs are constructed with the bottleneck structure. The arcs that block the negative cost augmented graph are the elements of the bottleneck. The bottleneck analysis for the generalized circulation problem, the minimum circulation problem and the circulation problem are discussed respectively as the basal problems, then that for MCPGN is achieved. An example is presented at the end.

关键词： bottleneck augmented forest minimum cost problem

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基于小波变换的工况区域识别

清华大学学报（自然科学版） 2000年第1期40卷 91-94页

作者：赵众金以慧蒋慰孙清华大学自动化系北京100084 华东理工大学自动化所上海200237

针对生产过程的特点 ,对过程工况区域识别问题进行了描述 ,在分析小波变换的基础上 ,研究了利用小波变换的多尺度分析特性 ,提取生产过程检测信号的多尺度定性变化特征 ,并分析和证明了提取的工况区域特征具有描述工况区域的稳定性和完... 详细信息

针对生产过程的特点 ,对过程工况区域识别问题进行了描述 ,在分析小波变换的基础上 ,研究了利用小波变换的多尺度分析特性 ,提取生产过程检测信号的多尺度定性变化特征 ,并分析和证明了提取的工况区域特征具有描述工况区域的稳定性和完备性。在此基础上 ,结合模式归纳分类算法 ,提出了一种基于小波变换的工况区域识别方法。应用实例研究。

关键词：小波变换多尺度分析工况区域识别过程控制

Stretchable polymer composites with ultrahigh piezoelectric performance

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National Science Review 2023年第8期10卷 203-210页

作者： Tongxiang Tang Zhonghui Shen Jian Wang Shiqi Xu Jiaxi jiang Jiahui Chang Mengfan Guo Youjun Fan Yao Xiao Zhihao Dong Houbing Huang Xiaoyan Li yihui Zhang Danyang Wang Long-Qing Chen Ke Wang Shujun Zhang Ce-Wen Nan Yang Shen State Key Lab of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Center of Smart Materials and Devices Wuhan University of Technology Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Applied Mechanics Laboratory Department of Engineering Mechanics Tsinghua University Center for Flexible Electronics Technology Tsinghua University School of Materials Science and Engineering University of New South Wales Department of Materials Science and Engineering The Pennsylvania State University State College Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of Wollongong

Flexible piezoelectric materials capable of withstanding large deformation play key roles in flexible electronics. Ferroelectric ceramics with a high piezoelectric coefficient are inherently brittle, whereas polar polymers exhibit a low piezoelectric coefficient. Here we report a highly stretchable/compressible piezoelectric composite composed of ferroelectric ceramic skeleton, elastomer matrix and relaxor ferroelectric-based hybrid at the ceramic/matrix interface as dielectric transition layers, exhibiting a giant piezoelectric coefficient of 250 picometers per volt, high electromechanical coupling factor keff of 65%,ultralow acoustic impedance of 3MRyl and high cyclic stability under 50% compression strain. The superior flexibility and piezoelectric properties are attributed to the electric polarization and mechanical load transfer paths formed by the ceramic skeleton, and dielectric mismatch mitigation between ceramic fillers and elastomer matrix by the dielectric transition layer. The synergistic fusion of ultrahigh piezoelectric properties and superior flexibility in these polymer composites is expected to drive emerging applications in flexible smart electronics.

关键词： polymer composites piezoelectric materials structure design flexible electronics

Reduction in polycyclic aromatic hydrocarbon exposure in Beijing following China’s clean air actions

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Science Bulletin 2024年第20期69卷 3283-3290页

作者： Yan Lin Xiaodi Shi Xinghua Qiu Xing jiang Jinming Liu Peiwen Zhong yihui Ge Chi-Hong Tseng Junfeng(Jim)Zhang Tong Zhu Jesus A Araujo Yifang Zhu SKL-ESPC&SEPKL-AERM College of Environmental Sciences and Engineeringand Center for Environment and HealthPeking UniversityBeijing 100871China Department of Environmental Health Sciences Jonathan and Karin Fielding School of Public HealthUniversity of California Los AngelesLos Angeles 90095USA Division of Cardiology Department of MedicineDavid Geffen School of Medicine at University of California Los AngelesLos Angeles 90095USA Nicholas School of the Environment and Global Health Institute Duke UniversityDurham 27708-0187USA

Exposure to polycyclic aromatic hydrocarbons(PAHs)in the Chinese population was among the highest globally and associated with various adverse *** study examines the impact of China’s twophase clean air initiatives,namely the Air Pollution Prevention and Control Action Plan(APPCAP)in2013–2017 and the Blue-Sky Defense War(BSDW)in 2018–2020,on PAH levels and human exposures in *** evaluate the effects of APPCAP,we measured 16 PAHs in 287 PM_(2.5)samples collected in Beijing and 9 PAH metabolites in 358 urine samples obtained from 54 individuals who traveled from Los Angeles to Beijing between 2014 and *** concentration of PM_(2.5)-bound benzo[a]pyrene equivalents(BaPeq)decreased by 88.5%in 2014–2018 due to reduced traffic,coal,and biomass *** metabolite concentrations in travelers’urine decreased by 52.3%in Beijing,correlated with changes in PM_(2.5)and *** contrast,no significant changes were observed in Los *** evaluate BSDW’s effects,we collected 123 additional PM_(2.5)samples for PAH measurements in 2019–*** observed sustained reductions in BaPeq concentrations attributable to reductions in coal and biomass emissions during the BSDW phase,but those from traffic sources remained *** accounting for meteorological factors,China’s two-phase clean air initiatives jointly reduced Beijing’s PM_(2.5)-bound BaPeq concentrations by 96.6%from 2014 to *** findings provide compelling evidence for the effectiveness of China’s clean air actions in mitigating population exposure to PAHs in Beijing.

关键词： Polycyclic aromatic hydrocarbons Air pollution Exposure biomarker Clean air action

Guidelines on multidisciplinary approaches for the prevention and management of diabetic foot disease(2020 edition)

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Burns & Trauma 2020年第1期8卷 217-268页

作者： Aiping Wang Guozhong Lv Xingbo Cheng Xianghua Ma Wei Wang Jianchao Gui JiHu Meng Lu Guoping Chu Jin’an Chen Hao Zhang Yiqiu jiang Yuedong Chen Wengbo Yang Lin jiang Houfa Geng Rendong Zheng yihui Li Wei Feng Boey Johnson Wenjuan Wang Dalong Zhu Yin Hu Diabetic Foot Centre The Air Force Hospital From Eastern Theater of PLANanjing210002China Department of Burn and Plastic Surgery Affiliated Hospital of Jiangnan UniversityWuxi214062China Department of endocrinology the First Affiliated Hospital of Suzhou UniversitySuzhou215006China Department of endocrinology Jiangsu Province HospitalNanjing210029China Vascular Surgery Gulou HospitalNanjing210008China Department of orthopedics Nanjing First HospitalNanjing210006China Department of endocrinology The Second Affiliated Hospital of Suzhou UniversitySuzhou215004China Department of endocrinology Xuzhou Central HospitalXuzhou221009China Department of endocrinology Jiangsu Province Hospital on Traditional of Chinese and Western Medicine210028China Operating department Jiangsu Medical AssociationNanjing210008China Diabetic Foot Centre The National University Hospital119077Singapore Department of Chronic Non-Communicable Diseases Chinese Center for Disease Control and PreventionBeijing102206China

In recent years,as living standards have continued to improve,the number of diabetes patients in China,along with the incidence of complications associated with the disease,has been *** these complications,diabetic foot disease is one of the main causes of disability and death in diabetic *** to the differences in economy,culture,religion and level of medical care available across different regions,preventive and treatment methods and curative results for diabetic foot vary *** multidisciplinary models built around diabetic foot,the timely assessment and diagnosis of wounds and appropriate methods of prevention and treatment with internal and external surgery are key to clinical practice for this *** 2019,under the leadership of the jiangsu Medical Association and Chinese Diabetes Society,the writing group for the Guidelines on multidisciplinary approaches for the prevention and management of diabetic foot disease(2020 edition)was established with the participation of scholars from the specialist areas of endocrinology,burn injury,vascular surgery,orthopedics,foot and ankle surgery and *** lessons from diabetic foot guidelines from other countries,this guide analyses clinical practices for diabetic foot,queries the theoretical basis and grades and gives recommendations based on the characteristics of the pathology in *** paper begins with assessments and diagnoses of diabetic foot,then describes treatments for diabetic foot in detail,and ends with protections for high-risk feet and the prevention of *** manuscript covers the disciplines of internal medicine,surgical,nursing and rehabilitation and describes a total of 50 recommendations that we hope will provide procedures and protocols for clinicians dealing with diabetic foot.

关键词： Diabetic foot disease Diabetic peripheral neuropathy Peripheral arterial disease Diabetic foot osteomyelitis Diabetic foot infection Diabetic complication Ankle-brachial index Transcutaneous oxygen pressure Recommendation Randomized controlled trials

C/C坯体密度对2D C_f/SiC复合材料结构和性能的影响

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复合材料学报 2016年第12期33卷 2840-2845页

作者：凌艺辉江品颐黄向东福州大学材料科学与工程学院福州350000 福州赛瑞特新材料技术开发有限公司福州350000

通过理论计算,探究C_f/SiC复合材料密度与C/C坯体密度的相关性;而后采用碳纤维布叠层制作2D C/C坯体,经先驱体浸渍裂解工艺增密,制得密度分别为0.98、1.06、1.12g/cm^3的C/C坯体,通过液相渗硅法反应合成2DC_f/SiC复合材料,探究C/C坯体... 详细信息

通过理论计算,探究C_f/SiC复合材料密度与C/C坯体密度的相关性;而后采用碳纤维布叠层制作2D C/C坯体,经先驱体浸渍裂解工艺增密,制得密度分别为0.98、1.06、1.12g/cm^3的C/C坯体,通过液相渗硅法反应合成2DC_f/SiC复合材料,探究C/C坯体密度对其结构和性能的影响。与理论计算结果来对比。研究结果表明:试验结果与理论数学计算结果基本一致。随着C/C坯体密度的增加,C_f/SiC复合材料的密度出现先上升后下降的趋势,当C/C坯体密度大于0.98g/cm^3后,复合材料的弯曲强度随着C/C坯体密度的增加而降低,C/C坯体密度为0.98g/cm^3时,2DC_f/SiC复合材料结构和性能较优。

关键词： 2D Cf/SiC复合材料 C/C坯体密度液相渗硅结构性能

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粉料粒度对氮化硅陶瓷性能的影响

中国粉体技术 2012年第3期18卷 48-52页

作者：江涌赵益辉北方民族大学材料科学与工程学院宁夏银川750021

用球磨的方式将平均粒径为6.46μm的β-氮化硅原料粉细化为不同粒度的亚微米级起始粉料,加入适宜的添加剂,以无压液相烧结的方法研究起始粉料粒度对氮化硅陶瓷的强度、硬度等机械性能的影响。用扫描电镜、X射线衍射等方法测试分析试样... 详细信息

用球磨的方式将平均粒径为6.46μm的β-氮化硅原料粉细化为不同粒度的亚微米级起始粉料,加入适宜的添加剂,以无压液相烧结的方法研究起始粉料粒度对氮化硅陶瓷的强度、硬度等机械性能的影响。用扫描电镜、X射线衍射等方法测试分析试样的显微结构、相组成等。结果表明,试样密度、强度、硬度等均随起始粉料粒度的减小而增大;试样显微结构显示了烧结体晶粒尺寸随起始粉料粒度的减小而减小,且粒度小的试样烧结的晶粒均匀、致密;烧结后试样的物相主要是β-氮化硅和少量黄长石,粉料的粒度对烧结后样品的物相没有影响。

关键词：粒度氮化硅陶瓷机械性能显微结构

脊椎髓外硬膜下血管瘤MRI征象与临床病理特征分析

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中华放射学杂志 2022年第2期56卷 201-204页

作者：杨欢江波潘碧涛马怡辉郑州大学第一附属医院放射科郑州450052 中山大学附属第一医院放射诊断科广州510080 郑州大学第一附属医院病理科郑州450052

本研究通过回顾性分析经病理证实的5例髓外硬膜下毛细血管瘤(CAPH)和3例髓外硬膜下海绵状血管瘤(CAVH)的临床病理与MRI资料,以探讨脊椎髓外硬膜下血管临床病理及MR特点。8例髓外硬膜下血管瘤位于脊椎胸段4例,腰段2例,颈胸段、腰骶段各1... 详细信息

本研究通过回顾性分析经病理证实的5例髓外硬膜下毛细血管瘤(CAPH)和3例髓外硬膜下海绵状血管瘤(CAVH)的临床病理与MRI资料,以探讨脊椎髓外硬膜下血管临床病理及MR特点。8例髓外硬膜下血管瘤位于脊椎胸段4例,腰段2例,颈胸段、腰骶段各1例。瘤体呈结节状,5例边缘光整,3例边缘分叶。CAPH以T_(1)WI等信号、T2WI稍高信号及显著强化为主,镜下为均质的毛细血管样血管结节;CAVH以T_(1)WI等信号、T_(2)WI稍高信号混杂极低信号及异质性强化为主,镜下可见出血及血栓。5例可见瘤周血管征,其中CAVH 1例,CAPH 4例。5例可见脊髓水肿,其中CAVH 2例,CAPH 3例。总之,脊椎髓外硬膜下血管瘤MRI表现多样,CAVH较CAPH更易发生出血;瘤周血管征和脊髓水肿是脊椎髓外硬膜下血管瘤的特征性MRI征象。

关键词：血管瘤,海绵状血管瘤,毛细管磁共振成像