检索结果-南通市图书馆

DC breakdown characteristics of XLPE/BNNS nanocomposites considering BN nanosheet concentration,space charge and temperature

在线全文

学校读者我要写书评

暂无评论

High Voltage 2020年第3期5卷 280-286页

作者： Guochang Li Xuguang zhou Xuejing Li Yanhui Wei Chuncheng Hao shengtao Li Qingquan Lei Institute of Advanced Electrical Materials Qingdao University of Science and TechnologyQingdaoPeople's Republic of China State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anPeople's Republic of China

Breakdown failure in insulation material is one of the key problems that threaten the safe operation of high-voltage direct current *** this work,the effect of boron nitride nanosheets(BNNSs)concentration,space charge and temperature on DC breakdown strength have been ***-linked polyethylene(XLPE)/BNNS nanocomposites were prepared by the melt blending method,and the basic characteristics of nanoparticles and composite were *** experimental results indicate that DC breakdown strength of nanocomposite can be effectively improved when a small amount of BN nanosheet is doped into the *** breakdown strength of the sample reaches the maximum value of 407.52 kV/mm when BNNS content is 0.5 wt%,which is about 33%higher than that of pure ***,the effect of space charge on the breakdown of nanocomposites has been studied by pre-injecting *** the samples with different BNNS contents,all the breakdown strength present ascending trend when the polarity of the applied voltage is the same as that of the pre-injected ***,it can be found that the breakdown strength of the XLPE/BNNSs composite decreases significantly at 50°C,which is due to more charge accumulation at 50°*** reaches 2.06×10^(−8)C which increases by about 2.2 times than the room temperature.

关键词： strength charge characteristics

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

一种模拟3 V锂电池供电的DC-DC设计

电子技术应用 2020年第9期46卷 47-50页

作者：杜培德李晓露朱文锦周盛涛褚祝军李亚情北方夜视技术股份有限公司云南昆明650223

微光像增强器采用3 V锂电池供电,随着电池电压下降,直流工作点变化或调整可能引起其内部高压电源输出异常,导致像管出现闪烁、熄灭或高亮等故障。通常使用具有“电池模拟功能”的直流电源进行供电特性验证,该类设备功率大,功能多,价格... 详细信息

微光像增强器采用3 V锂电池供电,随着电池电压下降,直流工作点变化或调整可能引起其内部高压电源输出异常,导致像管出现闪烁、熄灭或高亮等故障。通常使用具有“电池模拟功能”的直流电源进行供电特性验证,该类设备功率大,功能多,价格也昂贵,像增强器功率小,若采用这种设备则利用率低以至于研发成本高。基于恒流源控制LDO输出,设计一种模拟1.4 V^3.4 V锂电池充放电的DC-DC电路,经仿真和实测验证,输出电压能够线性上升或下降且速率可在数十毫秒至数小时内可调,具备模拟电池供电功能,该电路成本较低,其改进线路还可用于其它领域功率产品作直流扫描分析验证。

关键词：模拟电池供电恒流源控制直流扫描分析像增强器

Down-regulation of argininosuccinate lyase induces hepatoma cell apoptosis through activating Bax signaling pathway

在线全文

学校读者我要写书评

暂无评论

Genes & Diseases 2019年第3期6卷 296-303页

作者： Rui Gong Lin He HongZhong zhou shengtao Cheng Fang Ren Juan Chen JiHua Ren The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education Chongqing Medical University1 Yixueyuan RoadYuzhong DistrictChongqing400016China

Argininosuccinate lyase(ASL)plays an important role in the hepatic urea cycle,and can catalyze the reversible reaction of argininosuccinate to arginine and ***,the function of ASL in hepatocellular carcinoma(HCC)is not fully *** this study,we found that ASL expression was frequently upregulated in HCC tissues and HCC cell *** down of ASL inhibited cell proliferation and induced apoptosis in HCC *** studies revealed the BCL2-associated X protein(Bax)signaling pathway which determines cancer cell apoptosis was regulated by ***,the depletion of Bax restored the inhibition of cell growth and reduced apoptosis initiated by ASL ***,the study demonstrated that ASL regulated HCC cell growth and apoptosis by modulating Bax ***,the therapeutic targeting of ASL may offer options for HCC treatment.

关键词： Apoptosis ASL Bax HCC Proliferation

Two-dimensional van der Waals thin film transistors as active matrix for spatially resolved pressure sensing

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2021年第10期14卷 3395-3401页

作者： Chao Ma Dong Xu Peiqi Wang Zhaoyang Lin Jingyuan zhou Chuancheng Jia Jin Huang shengtao Li Yu Huang Xiangfeng Duan Department of Materials Science and Engineering University of CaliforniaLos AngelesCA 90095USA State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an 710049China Department of Chemistry and Biochemistry University of CaliforniaLos AngelesCA 90095USA

The development of pressure sensor arrays capable of distinguishing the shape and texture details of objects is of considerable interest in the emerging fields of smart robots,prostheses,human-machine interfaces,and artificial intelligence(AI).Here we report an integrated pressure sensor array,by combining solution-processed two-dimensional(2D)MoS2 van der Waals(vdW)thin film transistor(TFT)active matrix and conductive micropyramidal pressure-sensitive rubber(PSR)electrodes made of polydimethylsiloxane/carbon nanotube composites,to achieve spatially revolved pressure mapping with excellent contrast and low power *** demonstrate a 10×10 active matrix by using the 2D MoS2 vdW-TFTs with high on-off ratio>10^(6),minimal hysteresis,and excellent device-to-device *** combination of the vdW-TFT active matrix with the highly uniform micropyramidal PSR electrodes creates an integrated pressure sensing array for spatially resolved pressure *** study demonstrates that the solution-processed 2D vdW-TFTs offer a solution for active-matrix control of pressure sensor arrays,and could be extended for other active-matrix arrays of electronic or optoelectronic devices.

关键词： pressure sensor array van der Waals thin film transistor two-dimensional material active matrix micropyramids

细毛石花菜多糖自由基清除能力和理化性质的研究

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

食品与发酵工业 2022年第4期48卷 235-242页

作者：裴育杨胜涛冯瑞周春霞洪鹏志广东海洋大学食品科技学院广东省水产品加工与安全重点实验室广东省海洋食品工程技术研究中心广东湛江524088 南方海洋科学与工程广东省实验室(湛江) 广东湛江524025

该文通过研究细毛石花菜(Gelidium crinale)多糖提取物对自由基的清除能力及理化性质,为细毛石花菜的高值化加工利用提供实验依据。以细毛石花菜为原料,用0.1 mol/L的HCl提取制备细毛石花菜多糖,并对其理化性质和抗氧化活性进行研究。... 详细信息

该文通过研究细毛石花菜(Gelidium crinale)多糖提取物对自由基的清除能力及理化性质,为细毛石花菜的高值化加工利用提供实验依据。以细毛石花菜为原料,用0.1 mol/L的HCl提取制备细毛石花菜多糖,并对其理化性质和抗氧化活性进行研究。结果显示,细毛石花菜多糖中总糖占比为70.51%,还原糖占比为8.42%,硫酸基团占比为16.50%,蛋白质占比为5.27%。单糖组成分析表明,半乳糖含量最高,岩藻糖和木糖次之,相对分子质量为25.8 kDa。体外抗氧化实验结果显示,细毛石花菜多糖具有较好的抗氧化活性,其ABTS阳离子自由基清除能力、Fe^(2+)螯合能力、DPPH自由基清除能力和羟自由基清除能力的IC50分别为2.215、2.688、7.408、13.56 mg/mL。细胞实验结果显示,细毛石花莱多糖处理后细胞中的超氧化物歧化酶水平以剂量依赖的方式显著增加,对活性氧的产生有抑制作用(P<0.001)。

关键词：细毛石花菜多糖理化性质抗氧化

在线全文

学校读者我要写书评

暂无评论

水下航行体通气空化流动及其数值模拟研究

战术导弹技术 2022年第2期 120-130页

作者：崔祚向敏周后村刘圣陶贵州理工学院航空航天工程学院贵阳550003 国防科技大学空天工程学院长沙410003 中国空气动力研究与发展中心绵阳621000 北京遥测技术研究所北京100094

水下航行器大多采用人工通气的方法产生覆盖其表面的超空泡,实现不同航速下的高效减阻,但通气空化流动机理研究以及数值模拟方法尚不成熟。对此,结合通气空化流动现阶段研究成果,从空泡形态、空泡稳定性和空泡流动控制3个方面论述了实... 详细信息

水下航行器大多采用人工通气的方法产生覆盖其表面的超空泡,实现不同航速下的高效减阻,但通气空化流动机理研究以及数值模拟方法尚不成熟。对此,结合通气空化流动现阶段研究成果,从空泡形态、空泡稳定性和空泡流动控制3个方面论述了实验研究进展;阐述了数值模拟通气空泡的3类方法;从湍流模型和空泡界面捕捉方式两个方面重点讨论了通气空泡数值模拟研究的关键技术。研究表明,提高空泡稳定性和调控能力、研究多相可压空化流数值模拟方法以及小尺度空化流动微观物理机制将成为未来研究的方向,为后续通气空化流动研究以及水下超高速导弹研制提供参考。

关键词：通气空化空泡形态空泡稳定性流动控制湍流模型界面处理

拮抗炭疽病的茶树内生菌筛选、鉴定及培养条件优化

在线全文

学校读者我要写书评

暂无评论

茶叶科学 2023年第2期43卷 205-215页

作者：郑世仲周子维陈晓慧蔡烈伟江胜滔刘盛荣宁德师范学院生命科学学院福建宁德352100

为筛选高效拮抗茶树炭疽病的内生细菌,以茶树健康叶片为材料,采用平板对峙拮抗法进行筛选,并对筛选到的菌株进行鉴定、抑菌效果评价及培养条件优化。从分离的162株内生细菌中筛选到1株对茶树胶孢炭疽菌有较好抑制效果的拮抗细菌X13。形... 详细信息

为筛选高效拮抗茶树炭疽病的内生细菌,以茶树健康叶片为材料,采用平板对峙拮抗法进行筛选,并对筛选到的菌株进行鉴定、抑菌效果评价及培养条件优化。从分离的162株内生细菌中筛选到1株对茶树胶孢炭疽菌有较好抑制效果的拮抗细菌X13。形态学、生理生化鉴定及16 S rDNA系统进化发育分析显示,分离的菌株X13为枯草芽孢杆菌(Bacillus subtilis)。菌株X13对病原菌菌丝生长抑制率为61.6%。生长曲线表明,菌株X13对数生长期为接种后2~14 h。响应面优化的培养条件为4.0%(质量百分浓度)玉米粉,1.0%(质量百分浓度)的硝酸钠,接种量3.5%(体积分数)。本研究结果可为茶树炭疽病防治及生防菌剂的开发提供重要参考。

关键词：茶树炭疽病内生细菌枯草芽孢杆菌培养条件

The Application of GNSS to Fault Deformation Studies

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Earthquake Research in China 2014年第4期28卷 510-519页

作者： Bo Wanju Feng shengtao Su Jianfeng zhou Haitao Du Xuesong Wan Wenni Liu Tianhai The First Crustal Deformation Monitoring and Application Center CEA National Earthquake Response Support Service

Great earthquakes often occur along or near active fault belts. Thus,monitoring and research on fault deformation are quite important. Methods such as short-leveling,shortbaseline and integrated monitoring profile across fault belts have been used to monitor fault activities for many years. GNSS observations are mainly used to obtain the horizontal velocity field in large areas and to study the activities and deformation of major *** technology has been used to monitor and study the deformation of faults from a different aspects. In this paper,some applications and new explorations of GNSS are discussed. They are:( 1) Research and monitoring of strike-slip activities of faults with GNSS.( 2) Research and monitoring of vertical activities of faults with GNSS.( 3)Investigating the laws of deformation of blocks on the sides of fault zone and setting up strain models to deduce the activities and deformation of faults with respective models and compare the deduced results with the actual measurements across fault. It is concluded that a larger discrepancy between the deduced and the observed deformation indicates a stronger interaction between the blocks,which can be important for predicting the location of a strong earthquake and assessing seismic hazard,as well as the seismicity trend.

关键词：全球导航卫星系统断层形变应用监测信息 GNSS 地震活动趋势水平速度场地震危险性

在线全文

学校读者我要写书评

暂无评论

中国全球卫星导航信号基本框架设计

中国空间科学技术 2011年第4期31卷 9-14,29页

作者：谭述森周兵郭盛桃刘志俭北京环球信息中心北京100094

中国的全球卫星导航信号设计必须遵循许多约束条件,具备国际可协调性,导航信号的服务类型、载波中心频率、调制方式和伪随机码序列均需参加与GPS、Galileo进行的频率协调。依据参加与GPS频率协调的参考假设文件,描述了中国的全球卫星导... 详细信息

中国的全球卫星导航信号设计必须遵循许多约束条件,具备国际可协调性,导航信号的服务类型、载波中心频率、调制方式和伪随机码序列均需参加与GPS、Galileo进行的频率协调。依据参加与GPS频率协调的参考假设文件,描述了中国的全球卫星导航信号结构、基本参数、公开导航信号的伪随机扩频码序列和二次编码序列,计算表明伪随机扩频序列的性能与GPS信号伪随机扩频序列性能相当。

关键词：信号体制调制方式相关特性伪随机码北斗卫星导航系统