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Structural and electrical properties of high Curie temperature Aurivillius phase composite ceramics with largely enhanced piezoelectricity

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Science China(Technological Sciences) 2016年第7期59卷 1048-1053页

作者： wang yunli CAI Kai MA JingTao ZENG Fei GUO Dong Institute of Acoustics Chinese Academy of Sciences Beijing 100190 China Beijing Center for Physical and Chemical Analysis Beijing 100089 China School of Materials Science & Engineering Tsinghua University Beijing 100084 China School of Materials Science & Engineering Beihang University Beijing 100191 China

High performance piezoelectric ceramics with high Curie temperatures(TC) are the bottle necks of relevant high temperature devices. In this study, the electrical performance and microstructure of Li and Mn codoped Aurivillius-type composite ceramics with a composition Ca_(0.99-x_Bi_(6.99+x)(Li Mn)_(0.01) Nb Ti_5O_(24)(x = 0–0.8) were systematically investigated. The results indicated that uniform intergrowth structure with a lattice similar to that of the end member CBT could be formed at a low x value(x < 0.4). Phase separation occurred when more A-site Ca^(2+) ions were replaced by Bi^(3+) ions. Nevertheless, all composite samples showed d_(33) values about 2 to 3 times of that of the constituent phase Ca Bi_4Ti_4O_(15) and Bi_3 Ti NbO_9 with still a high depolarization temperature. The performance of the samples was found to be related to the density and larger lattice distortion along the polarization a axis. The results also demonstrated that formation of the compound system was an effective way in improving the performance of Aurivillius-type high TC piezoelectric ceramics.

关键词： piezoelectric ceramics Curie temperature ferroelectricity dielectric properties

Correlation of vascular endothelial growth factor to permeability of blood-brain barrier and brain edema during high-altitude exposure

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Neural Regeneration Research 2009年第10期4卷 775-779页

作者： Qiquan Zhou Chang'e Liu Jing wang yunli wang Bo Zhou Department of High Altitude Disease College of High Altitude Military Medicine Third Military Medical University of Chinese PLA Chongqing 400038 China Key Laboratory of High Altitude Medicine Ministry of Education and Key Laboratory of High Altitude Physiology and High Altitude Disease of Chinese PLA Chongqing 400038 China Department of Animal Science College of Basic Medicine Third Military Medical University of Chinese PLA Chongqing 400038 China Department of Pathology and Pathophysiology Chengdu Medical College Chengdu 610083 Sichuan Province China Clinical Laboratory the25 Hospital of Chinese PLA Jiuquan 735000 Gansu Province China

BACKGROUND： Many studies have evaluated the role of vascular endothelial growth factor （VEGF） in traumatic brain edema and hemorrhagic brain edema. OBJECTIVE： To observe the effects of VEGF expression on permeability of the blood-brain barrier （BBB） during high-altitude and hypoxia exposure, and to investigate the correlation between VEGF expression and BBB permeability with regard to Evans blue staining and brain edema during high-altitude exposure. DESIGN, TIME AND SETTING： The randomized, controlled, animal study was performed at the Tanggula Etape, Central Laboratory of Chengdu Medical College, and Central Laboratory of General Hospital of Chengdu Military Area Command of Chinese PLA, China, from July 2003 to November 2004. MATERIALS： Quantitative RT-PCR kit （Sigma, USA）, VEGF ELISA kit （Biosource, USA）, and Evans blue （Jingchun, China） were acquired for this study. METHODS： A total of 180 Wistar rats were equally and randomly assigned to 15 groups： low-altitude （500 m）, middle-altitude （2 880 m）, high-altitude （4 200 m）, super-high-altitude （5 000 m）, 1,3, 5, 7, 9, 11, 13, 15, 17, 19, and 21 days of super high-altitude exposure. Wistar rats were exposed to various altitude gradients to establish a hypoxia model. MAIN OUTCOME MEASURES： Brain water content was calculated according to the wet-to-dry weight ratio. BBB permeability to Evans blue was determined by colorimetric method. VEGF mRNA and protein levels in brain tissues were detected using RT-PCR and double-antibody sandwich ELISA. RESULTS： Brain water content, BBB permeability to Evans blue, and VEGF mRNA and protein levels in brain tissues increased with increasing altitude and prolonged exposure to altitude. The greatest increase was determined on day 9 upon ascending 5 000 m. Simultaneously, VEGF expression positively correlated to BBB permeability of Evans blue and brain water content （r = 0.975, 0.917, P〈 0.01）. CONCLUSION： Increased VEGF protein and mRNA expression was responsible for increased BBB p

关键词： high-altitude blood-brain barrier permeability vascular endothelial growth factor

Effect of minor Sc addition on microstructure and stress corrosion cracking behavior of medium strength Al–Zn–Mg alloy

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Journal of Materials Science & Technology 2018年第7期34卷 1172-1179页

作者： Zhaoming Li Haichang Jiang yunli wang Duo Zhang Desheng Yan Lijian Rong CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research. Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

Influence of Sc content on microstructure and stress corrosion cracking behavior of medium strength AI-Zn-Mg alloy have been investigated by optical microscopy, scanning electron microscopy, electron backscatter diffraction, transmission electron microscopy and slow strain rate test. The results indicate that the addition of Sc results in the formation of the quaternary coherent AI3（Sc, Zr, Ti） dispersoids during homogenization treatment, which will inhibit the dynamic recrystallization behavior. The number density ofAl3（Sc, Zr, Ti） particles increases with the increase of Sc content, and thus the recrystallization fraction of hot-extruded alloy is reduced and the peak strength in two-stage artificial aging sample is enhanced. At the same time, the wide of precipitation free zone is reduced, and the content of Zn and Mg in grain boundary particles and precipitation free zone is increased with the increase of Sc content. In peak-aged state, the 0.06 wt% Sc added alloy shows the better stress corrosion cracking resistance than the Sc-free alloy because of the reduction of recrystallization fraction and the interrupted distribution of grain boundary precipitates along grain boundary. However, the further addition of Sc to 0.11 wt% will result in the deterioration of stress corrosion cracking resistance due to the increase of electrochemical activity of grain boundary particles and precipitation free zone as well as hydrogen embrittlement.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Aluminium alloy Al3 (Sc Zr Ti) Recrystalization Stress corrosion cracking

Accumulation of carotenoids and expression of carotenoid biosynthesis genes in fruit flesh during fruit development in two Cucurbita maxima inbred lines

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Horticultural Plant Journal 2021年第6期7卷 529-538页

作者： Yusong Luo Chaojie wang Manman wang yunli wang Wenlong Xu Hongyu Han Zhichao wang Yujuan Zhong Hexun Huang Shuping Qu Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(Northeast Region) Ministry of Agriculture and Rural Affairs/Northeast Agricultural UniversityHarbin150030China College of Horticulture and Landscape Northeast Agricultural UniversityHeilongjiangHarbin150030China Vegetable Research Institute Guangdong Academy of Agricultural SciencesGuangzhou 510640China

Mesocarp color is an important agronomic trait of Cucurbita maxima and is determined mainly by the contents and compositions of the *** two inbred lines with significant differences in fruit flesh color were used in the study,the orange’312-1’and white’98-2’.Changes in seven carotenoid contents and compositions in the flesh of fruit produced by inbred lines’312-1’and’98-2’were analyzed during fruit *** expression of eight key carotenoid biosynthesis genes in the fruit flesh were investigated during five fruit development stage in two inbred *** the flesh color intensified,the orange flesh color of’312-1’was determined mainly by the increased contents of lutein,β-carotene and zeaxanthin and the lack of carotenoid accumulation led to the formation of white flesh in’98-2’*** expression of the LCY-e and CHYb genes was significantly stronger in’312-1’than in’98-2’,and their expression was strongly correlated with lutein andβ-carotene contents during fruit *** study provides a deep understanding of the molecular mechanism of carotenoid biosynthesis in fruit flesh and provides a basis for additional studies on the highly refined improvement of squash quality.

关键词： Cucurbita maxima Flesh color Lutein β-carotene Zeaxanthin

A Comprehensive Study of the High Temperature Performance and Microstructure of Different High Tc Piezoelectric Ceramics

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功能材料信息 2016年第1期13卷 57-58页

作者： Dong Guo Kai Cai yunli wang Beihang University Beijing 100191 China Beijing Center for Physical and Chemical Analysis Beijing 100089 China Institute of Acoustics Chinese Academy of Sciences Beijing 100190 China

The expanding demand for piezoelectric devices working at elevated temperatures,particularly those for aerospace and automotive industries,has stimulated a great deal of research effort on high Cu-rie Temperature(T C)... 详细信息

关键词：英语阅读理解陶瓷材料

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浅谈电网中各电压等级下的谐波电压问题

轻金属 2001年第12期 51-52页

作者：王云利包头铝厂内蒙古包头014046

对国家标准GB/T14 5 49-93《电能质量公用电网谐波》中谐波电压限值的确定作了说明。分析了 0 38kV电压等级的电压总谐波畸变率限值取 5 %为国家标准的合理性。提出了相邻各电压等级总谐波畸变率限值所应取比值的计算式。并结合我国电... 详细信息

对国家标准GB/T14 5 49-93《电能质量公用电网谐波》中谐波电压限值的确定作了说明。分析了 0 38kV电压等级的电压总谐波畸变率限值取 5 %为国家标准的合理性。提出了相邻各电压等级总谐波畸变率限值所应取比值的计算式。并结合我国电网枢纽点额定容量和短路容量的平均情况 ,提出了一个典型的 ,包含了 0 38、10、35、110kV以及 2 2 0kV各电压等级的供电网络接线。通过它作了计算 ,并参照其结果。

关键词：谐波电压谐波畸变率电网电能质量

1959—2022年青海省食源性肉毒中毒事件流行病学分析

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中国食品卫生杂志 2024年第2期36卷 207-211页

作者：王云丽郭学斌青海大学医学部公共卫生系青海省疾病预防控制中心青海西宁810000

目的分析青海省食源性肉毒中毒事件流行特征及影响因素,为防控提供科学依据。方法收集1959—2022年青海省肉毒中毒数据,应用Excel 2021进行流行病学特征分析,利用R 4.2.3对事件数和病死率进行Mann-Kendall趋势检验,运用ArcGis 10.2软件... 详细信息

目的分析青海省食源性肉毒中毒事件流行特征及影响因素,为防控提供科学依据。方法收集1959—2022年青海省肉毒中毒数据,应用Excel 2021进行流行病学特征分析,利用R 4.2.3对事件数和病死率进行Mann-Kendall趋势检验,运用ArcGis 10.2软件制作空间分布图。结果1959—2022年发生食源性肉毒中毒事件86起,发病348人,死亡195人,病死率为56.03%。中毒主要发生在第二、三季度,牧民为主要的发病人群,肉毒毒素型别主要为E型,“风干肉”为主要的中毒食品,生食和开锅即食为主要的食用方式。结论青海省食源性肉毒中毒病死率整体呈下降趋势,发病地区也逐渐缩小,但作为我国高发地区之一,病死率仍处于较高水平,应进一步加强对高危人群食品安全教育,提高基层医疗机构对肉毒中毒的救治能力,减少中毒事件的发生和死亡。

关键词：肉毒杆菌肉毒毒素食源性致病菌青海

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活性红195在中性电解质溶液中的聚集行为

纺织学报 2019年第4期40卷 77-82页

作者：王阿明夏良君王运利武汉纺织大学纺织新材料与先进加工技术国家重点实验室培育基地湖北武汉430200 迪肯大学前沿材料研究院

为研究染料聚集行为及其对染色上染率的影响,将不同质量浓度的6种中性电解质加入到活性红195染料溶液中,借助紫外-可见分光光度计和激光粒度仪等研究了活性红195染料在不同电解质溶液中的聚集行为,并探讨了电解质对染色上染率的影响。... 详细信息

为研究染料聚集行为及其对染色上染率的影响,将不同质量浓度的6种中性电解质加入到活性红195染料溶液中,借助紫外-可见分光光度计和激光粒度仪等研究了活性红195染料在不同电解质溶液中的聚集行为,并探讨了电解质对染色上染率的影响。结果表明:随着电解质质量浓度的增大,染料聚集程度增大;常温下,6种金属离子对染料聚集的影响程度依次为Al^(3+)> Ca^(2+)> Mg^(2+)> K^+> Na^+> Li^+;电解质中所含金属离子的离子半径越大、化合价越高,越易引发染料聚集,其中金属离子的化合价是影响染料聚集的主要因素;染色时染料聚集程度越大,上染率越高。

关键词：活性染料电解质聚集行为粒径上染率

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清代纺织品中明黄色色彩研究

故宫博物院院刊 2022年第5期241卷 122-132,139页

作者：王允丽王春蕾故宫博物院文保科技部

清代典制文献中对于服饰颜色的使用有详细规定,“明黄色”是等级最高的一种。本文在对故宫博物院藏纺织品整理与研究的过程中,发现清代同种颜色名称的纺织品普遍存在色差。作者通过对档案记录为“明黄色”的实物进行科学检测,给出其色度... 详细信息

清代典制文献中对于服饰颜色的使用有详细规定,“明黄色”是等级最高的一种。本文在对故宫博物院藏纺织品整理与研究的过程中,发现清代同种颜色名称的纺织品普遍存在色差。作者通过对档案记录为“明黄色”的实物进行科学检测,给出其色度值,讨论其色度范围,同时结合清代服饰图样及根据内务府档案中的染料配方进行复染试验,分析了“明黄色”色彩存在差异的原因。此项研究对于客观认识清代纺织品色彩分类有积极意义,也为探讨清代冠服制度等提供了可参考的依据。

关键词：清代纺织品明黄色分光测色仪古代服饰研究