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Journal of Materiomics 2024年第2期10卷 416-422页

作者： Jianwei Zhao Hailan Qin Xiaoxin Chen shuhui yu Dawei Wang Shenzhen Institute of Advanced Electronic Materials Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055GuangdongChina College of Materials Science and Engineering Guilin University of TechnologyGuilin541004GuangxiChina Functional Materials and Acousto-Optic Instruments Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin150080HeilongjiangChina

A number of CaHfO_(3)modified BiFeO_(3)-0.33BaTiO_(3)(BF-0.33BT-xCH)lead-free piezoceramics were fabri-cated through the solid-state sintering method and comprehensively investigated in this *** the optimal sintering temperature,all compositions display a typical perovskite structure in a pseudo-cubic phase with slightly larger lattice parameters as the CH content *** electrical resistivity is highly enhanced due to the addition of ***,including the grain morphology,core-shell structure,and chemistry inhomogeneities,are demonstrated upon different BF-0.33BT-xCH *** particular,the core-shell structures with non-uniform element distributions in the compositions can be eliminated by adding sufficient CH content(x>0.05).The highest saturation polarization(40.1 mC/cm^(2)),remnant polarization(26.8 mC/cm^(2)),and converse piezoelectric coefficient(290 pm/V)are achieved in the BF-0.33BT-0.01CH piezoceramic,which are significantly enhanced in comparison with the undoped BF-0.33BT *** further increasing the CH content,the piezoelectric properties of BF-0.33BT-xCH ceramics decline rapidly,and they start to exhibit characteristics of relaxor ferroelectrics.

关键词： Lead-free piezoelectric CaHfO_(3)modified BF-0.33BT Core-shell structure Impedance Piezoelectric property

通信噪音条件下非光滑优化问题的分布式derivative-free方法

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数学进展 2024年第1期53卷 193-214页

作者：李国强余淑辉贵州财经大学数学与统计学院贵州贵阳550025 贵州财经大学大数据统计学院贵州贵阳550025

本文研究了时变有向图上的非光滑分布式优化.在这样的图中,网络拓扑不仅是强连通的,而且还存在通信噪音.每个节点只能访问其非平滑的局部成本函数.本文给出了一种derivative-free分布式方法来最小化该网络中所有节点的成本函数之和.然... 详细信息

本文研究了时变有向图上的非光滑分布式优化.在这样的图中,网络拓扑不仅是强连通的,而且还存在通信噪音.每个节点只能访问其非平滑的局部成本函数.本文给出了一种derivative-free分布式方法来最小化该网络中所有节点的成本函数之和.然后建立了所提出方法的收敛性分析,并获得了收敛速度的显式复杂性界限.当每个局部成本函数都是凸的时,我们的分析表明,所提出的算法以■的速率收敛,收敛速率取决于噪声的上限、光滑参数以及网络信息传播速度和节点间不平衡影响.当每个局部成本函数fi是强凸时,我们得到了O(lnt/t)的更快的收敛速度.最后,用一个数值实验来展示所提出方法的收敛性.

关键词：分布式优化凸优化 derivative-free算法通信噪音

Texture Evolution Induced by Deformation in Aluminum Alloy

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上海交通大学学报 2004年第Z2期38卷 206-211页

作者： Zhao Yixi Lin zhongqin Li shuhui yu zhongqi School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China

The lower formability of aluminum alloy sheets is the inherent characteristic of the material. During material forming processes the material undergoes a complex strain history. In this paper, the effect of crystallographic texture induced by deformation in aluminum sheet is studied. The transformation of crystallographic textures induced by uniaxial tensile, cup drawing and bulge tests was measured through X-ray diffraction and analyzed. The author studied the texture evolution rule under different strain paths. A qualitative relationship between the deformation and texture evolution has been founded.

关键词： texture evolution aluminum alloy deformation strain path

新生儿科护士早产儿体位支持行为评估量表的编制及信效度检验

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护理研究 2024年第6期38卷 1107-1111页

作者：蒙景雯李变于书慧葛侯睿杜雪燕北京大学第一医院北京100034

目的:编制新生儿科护士早产儿体位支持行为评估量表并验证其信效度。方法:以健康行为改变的多理论模型为指导,通过文献回顾形成新生儿科护士早产儿体位支持行为评估量表初稿,通过专家小组讨论对量表初稿条目进行修订,通过专家函询、预... 详细信息

目的:编制新生儿科护士早产儿体位支持行为评估量表并验证其信效度。方法:以健康行为改变的多理论模型为指导,通过文献回顾形成新生儿科护士早产儿体位支持行为评估量表初稿,通过专家小组讨论对量表初稿条目进行修订,通过专家函询、预调查形成新生儿科护士早产儿体位支持行为评估量表。采用便利抽样法对203名新生儿重症监护室(NICU)和新生儿科病房临床护士进行测评,检验量表信效度。结果:新生儿科护士早产儿体位支持行为评估量表包括4个维度(体位支持的意义、体位支持的自我努力与社会支持、体位支持的物理环境支持、体位支持的信心),共25个条目。探索性因子分析显示,4个维度的累计方差贡献率为87.143%。量表水平的内容效度指数为0.941。量表总体的Cronbach′s α系数为0.972,折半信度为0.765,重测信度为0.862。结论:新生儿科护士早产儿体位支持行为评估量表具有良好的信效度,可用于护士的早产儿支持行为评估。

关键词：早产儿体位支持多理论模型德尔菲法信度效度护理

Advanced electrospinning nanomaterials:From spinning fabrication techniques to electrochemical applications

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Nano Research 2024年第8期17卷 7077-7116页

作者： Jie Zhang Miao yu shuhui Tao College of Materials Science and Engineering Sichuan UniversityChengdu 610065China School of Mechanical Engineering Sichuan UniversityChengdu 610065China National University of Singapore(Chongqing)Research Institute Chongqing 401123China

Fuel cells,rechargeable metal–air batteries,metal-ion batteries,and supercapacitors have been regarded as prospective energy sources technologies to replace the fossil ***,electrochemical sensors also have been successfully developed as promising platforms for detecting pollutants,drug analysis,and healthcare *** is a scalable and suitable technique to design and fabricate diverse nanofibers and their nanocomposites for key components in electrochemical ***,a comprehensive review of electrospinning,from the technological innovations to the novel electrospun composite nanofibers,is *** importantly,the recent advances on the diverse components of electrochemical devices are highlighted,followed with the detailed discussion about the corresponding enhancement mechanism based on the electrospun ***,the currently faced challenges on the fabrication of electrospun nanomaterials are raised and a brief perspective for the future development of electrospun nanomaterials-based electrochemical applications is prospected.

关键词： electrospinning carbon nanofibers metal-organic frameworks electrode materials electrochemical applications

Surface-modified barium titanate by MEEAA for high-energy storage application of polymer composites

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High Voltage 2016年第4期1卷 175-180页

作者： Yanbin Shen Suibin Luo shuhui yu Rong Sun Ching-Ping Wong Center for Advanced Materials Research Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenPeople’s Republic of China Department of Nano Science and Technology Institute Nano Science and Technology InstituteUniversity of Science and Technology of ChinaSuzhouPeople’s Republic of China Faculty of Engineering The Chinese University of Hong KongHong KongPeople’s Republic of China

In this study,2-[2-(2-methoxyethoxy)ethoxy]acetic acid(MEEAA)was used to modify the surface of barium titanate nanoparticles(BT NPs)to enhance the compatibility and dispersion of the BT ceramic fillers in polymer matrix.A uniform coating layer with a thickness about 2 nm was formed on the surface of BT after *** poly(vinylidene fluoride)-hexafluoropropene[P(VDF-HFP)]composites filled with MEEAA-modified BT NPs achieved higher permittivity(∼13 at 3.0 vol%filler)and discharged energy density than that of the untreated BT filled *** maximum discharge energy density of 7.8 J/cm^(3)was obtained in the nanocomposites with 3 vol%MEEAA-modified BT NPs at electric field of 425 kV/mm,which is 77%higher than that of 4.4 J/cm^(3)of pure P(VDF-HFP)film at electric field of 420 kV/mm.

关键词： composites barium modified

术前盆底肌电生理参数对前列腺癌根治性切除术后早期尿失禁的预测价值

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北京大学学报（医学版） 2024年第4期56卷 594-599页

作者：于书慧韩佳凝钟丽君陈聪语肖云翔黄燕波杨洋车新艳北京大学第一医院泌尿外科北京100034 北京大学护理学院北京100191

目的:探索术前盆底肌电生理参数对前列腺癌术后尿失禁风险的预测价值。方法:选择2020年1月至2022年10月在北京大学第一医院泌尿外科行根治性前列腺切除术患者的病例资料进行回顾性分析,记录患者的年龄、体重指数(body mass index,BMI)... 详细信息

目的:探索术前盆底肌电生理参数对前列腺癌术后尿失禁风险的预测价值。方法:选择2020年1月至2022年10月在北京大学第一医院泌尿外科行根治性前列腺切除术患者的病例资料进行回顾性分析,记录患者的年龄、体重指数(body mass index,BMI)、国际前列腺症状评分(international prostate symptom score,IPSS)、前列腺特异性抗原(prostate-specific antigen,PSA)水平、Gleason评分、手术方式、是否尿道功能重建、是否淋巴结清扫、性神经是否保留、留置导尿时间、D’Amico风险分级、美国麻醉医师协会(American Society of Anesthesiologists,ASA)评分、查尔森(Charlson)合并症指数、术后随访时间、前列腺体积,以及盆底肌电生理参数(前静息均值、快肌均值和慢肌均值)。通过多因素Logistic回归分析,筛选出影响术后早期尿失禁发生的独立危险因素,并通过计算受试者工作特征曲线(receiver operating characteristic,ROC)下面积,评估盆底肌电参数的预测效能,再利用约登指数(Youden index)并结合临床意义,共同确定术后早期尿失禁发生的最佳临界值。结果:纳入患者271例,术后自主控尿率为81.9%。患者快肌评分为23.5(18.2,31.6)分,慢肌评分为12.5(9.6,17.3)分,179例(66.1%)患者未保留性神经,110例(40.6%)患者进行了尿道功能重建。高龄和盆底快肌评分低被确认为尿失禁发生的独立危险因素。≤60岁患者是≥70岁患者自主控尿率的5.482倍(95%CI:1.532~19.617,P<0.05);患者的盆底快肌评分与尿失禁恢复的关系密切(OR=1.209,95%CI:1.132~1.291,P<0.05)。当术前盆底快肌评分的最佳临界值设定为18.5分时,ROC的敏感度和特异度分别为80.6%和61.2%。结论:术前盆底肌电生理参数对于前列腺癌术后尿失禁风险表现出较好的预测准确性和临床应用性,能够用于前列腺癌术后尿失禁风险的早期识别,其中年龄和盆底快肌评分是重要的预测因子。

关键词：盆底肌电生理参数前列腺癌根治性切除尿失禁

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北方平原区农村低效建设用地空间格局与影响因素分析——以深泽县为例

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河北地质大学学报 2024年第5期47卷 108-112页

作者：齐志国张浩然白雪宇雯张红娟白浩然于淑会河北地质大学土地科学与空间规划学院河北石家庄050031 河北省农业干旱遥感监测国际联合研究中心河北石家庄050031

优化农村低效建设用地空间格局可协调城乡布局、改善乡村用地结构以及促进农村低效建设用地可持续发展。以河北省深泽县农村低效建设用地的斑点数据为基础,借助ArcGIS10.8软件平台的空间分析功能,经过密度分析、标准差椭圆分析等方法,... 详细信息

优化农村低效建设用地空间格局可协调城乡布局、改善乡村用地结构以及促进农村低效建设用地可持续发展。以河北省深泽县农村低效建设用地的斑点数据为基础,借助ArcGIS10.8软件平台的空间分析功能,经过密度分析、标准差椭圆分析等方法,定量研究深泽县农村低效建设用地空间格局,同时运用SPSS 22.0软件与有序Probit模型探讨了深泽县农村建设用地低效利用的影响因素。结果表明:深泽县农村低效建设用地总面积较大、分布广泛,深泽县农村低效建设用地在空间分布上具有十分显著的分异特征;基础设施、历史、产业、位置四种因素是影响深泽县农村低效建设用地形成的主要因素。研究结果为深泽县农村优化用地结构、统筹资源配置及实现土地的可持续利用提供参考。

关键词：农村低效建设用地空间格局影响因素二次开发

花生与绿肥轮作对土壤含水量和土壤肥力的影响

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中国农学通报 2024年第8期40卷 74-79页

作者：于淑慧朱国梁牟小翎董浩史桂芳郑铮张卫建泰安市农业科学院山东泰安271000 中国农业科学院作物科学研究所/农业农村部作物生理生态重点实验室北京100081

探讨在冬春裸地上种植绿肥对后茬作物春花生养分含量、土壤含水量和土壤肥力的影响,为山东地区春花生等冬闲田建立一种合理的轮作方式提供理论依据。在田间试验条件下,设置了春花生—冬闲田、夏花生—冬小麦、春花生—二月兰和春花生—... 详细信息

探讨在冬春裸地上种植绿肥对后茬作物春花生养分含量、土壤含水量和土壤肥力的影响,为山东地区春花生等冬闲田建立一种合理的轮作方式提供理论依据。在田间试验条件下,设置了春花生—冬闲田、夏花生—冬小麦、春花生—二月兰和春花生—毛叶苕子4种轮作处理。结果表明:种植二月兰和毛叶苕子绿肥作物,可促进后茬作物花生氮磷钾养分增加,二月兰增加程度高于毛叶苕子。种植二月兰和毛叶苕子绿肥作物,可提高后茬作物花生土壤含水量和土壤肥力,在0~20 cm土层中,2021年,与春花生—冬闲田相比,春花生—二月兰、春花生—毛叶苕子土壤相对含水量分别升高了4.70%、6.14%,在20~40、40~60 cm土层中也表现出相似趋势,2022年与2021年相比,表现出相似规律;与春花生—冬闲田相比,春花生—二月兰处理有机质、碱解氮、有效磷和速效钾含量平均增加了5.71%、8.98%、7.22%和7.72%,春花生—毛叶苕子处理有机质、碱解氮含量平均增加了4.54%、14.91%。可以利用春花生种植期间的冬春裸地种植一季冬绿肥,促进后茬作物养分积累量增加,改善土壤肥力。

关键词：春花生二月兰毛叶苕子土壤含水量土壤肥力

Construction of MnS/MoS_(2) heterostructure on two-dimensional MoS_(2) surface to regulate the reaction pathways for high-performance Li-O_(2) batteries

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Journal of Energy Chemistry 2024年第6期93卷 443-452,I0012页

作者： Guoliang Zhang Han yu Xia Li Xiuqi Zhang Chuanxin Hou shuhui Sun Yong Du Zhanhu Guo Feng Dang Key Laboratory for Liquid-Solid Structure Evolution and.Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061ShandongChina School of Environmental and Material Engineering Yantai UniversityYantai 264005ShandongChina Institute National de la Recherche Scientifique CentreÉnergie Matériaux et TélécommunicationsVarennesQuébec J31S2Canada State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083HunanChina Integrated Composites Lab Department of Mechanical and Construction EngineeringNorthumbria UniversityNewcastle Upon TyneNE18STUK

The inherent catalytic anisotropy of two-dimensional(2D) materials has limited the enhancement of LiO_(2) batteries(LOBs) performance due to the significantly different adsorption energies on 2D and edge *** the adsorption strength in 2D materials to the reaction intermediates is essential for achieving high-performance ***,a MnS/MoS_(2) heterostructure is designed as a cathode catalyst by adjusting the adsorption behavior at the *** from the toroidal-like discharge products on the MoS_(2) cathode,the MnS/MoS_(2) surface displays an improved adsorption energy to reaction species,thereby promoting the growth of the film-like discharge *** can disturb the layer growth of MoS_(2),in which the stack edge plane features a strong interaction with the intermediates and limits the growth of the discharge *** and theoretical results confirm that the MnS/MoS_(2) heterostructure possesses improved electron transfer kinetics at the interface and plays an important role in the adsorption process for reaction species,which finally affects the morphology of Li_2O_(2),In consequence,the MnS/MoS_(2) heterostructure exhibits a high specific capacity of 11696.0 mA h g^(-1) and good cycle stability over 1800 h with a fixed specific capacity of 600 mA h g^(-1) at current density of100 mA g^(-1) This work provides a novel interfacial engineering strategy to enhance the performance of LOBs by tuning the adsorption properties of 2D materials.

关键词： Li-O_(2)batteries Two-dimensional materials MnS/MoS_(2)heterostructure Edge plane Adsorption behavior