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统计与神经网络相结合的词义消歧模型
鸿
武汉理工大学学报 , 2006,
Abstract: ?介绍了一种基于bp神经网络和统计方法相结合的有导词义消歧模型,阐述了bp神经网络原理,通过对使用这种混合人工智能的消歧模型的可能性和优越性进行了讨论,最后通过试验发现实际和预测结果的误差并不随着试验迭代次数而递减,而是实际误差随着次数的增加在零的附近呈现波动状态,即使用很少的迭代次数也可以得到比较好的结果。
Tb1-xDyxFe2-y-BaTi0.99Mn0.01O3+δ层状复合材料的低频磁电耦合
鸿,刘清惓,王友保
复合材料学报 , 2013,
Abstract: 利用弹性力学模型,推导了低频下磁致伸缩-压电双层复合材料中磁电电压系数的表达式,计算了Tb1-xDyx-Fe2-y-BaTiO3层状复合材料中的横向磁电耦合。采用溶胶-凝胶法制备1.0%(摩尔分数)Mn掺杂BaTiO3(BaTi0.99Mn0.01O3+δ)压电陶瓷片。将Mn掺杂BaTiO3与Tb1-xDyxFe2-y胶合制成双层和三层复合材料,研究了复合材料在低频下的横向磁电效应。XRD和DSC分析结果表明,室温下Mn掺杂BaTiO3保持了其四方钙钛矿结构,降低了BaTiO3的居里点和相变潜热。在约33kA/m偏置磁场下,Tb1-xDyxFe2-y-BaTi0.99Mn0.01O3+δ和Tb1-xDyxFe2-y-BaTi0.99Mn0.01O3+δ-Tb1-xDyxFe2-y的横向磁电耦合峰值分别为529.4mV/A和1659.5mV/A,分别是Tb1-xDyxFe2-y-BaTiO3和Tb1-xDyxFe2-y-BaTiO3-Tb1-xDyxFe2-y的1.48和1.45倍。三层复合材料的横向磁电电压系数约是同类双层的3倍多。
水分胁迫对蔓生紫薇和亮叶忍冬生长及生理特性的影响
骆建,史燕山,鸿,王丹,李建科,武春
园艺学报 , 2006,
Abstract: 采用盆栽试验法,研究水分胁迫对蔓生紫薇(lagerstroemiaindica‘summerandsummer’)和亮叶忍冬(loniceranitida‘maigrun’)两种木本地被植物生长及生理特性的影响。结果表明:水分胁迫下,两种植物的生长受到明显抑制,蔓生紫薇受抑制程度高于亮叶忍冬,其相对生长量远小于亮叶忍冬。水分胁迫使两种植物净光合速率、蒸腾速率、气孔导度下降,胞间co2浓度则前期下降后期上升,且表现为蔓生紫薇各生理指标的变化幅度大于亮叶忍冬。综合评价两种植物的抗旱性为:亮叶忍冬>蔓生紫薇。
Elastomechanical study of interface coupling in magnetoelectric bilayers
磁电双层膜层间耦合的弹性力学研究

Cao Hong-Xia,Zhang Ning,
鸿
,张宁

物理学报 , 2008,
Abstract: 基于磁致伸缩相与压电相的本构方程,应用弹性力学模型,简要介绍了如何推导自由状态的磁电双层膜纵向、横向磁电(ME)电压系数. 并采用相应的材料参数计算了La07Sr03MnO3-Pb(Zr,Ti)O3 (LSMO-PZT),Tb1-xDyxFe2-y(TDF)-PZT双层膜中的磁电电压系数,具体分析了其与压电相
Magnetoelectric effect in transition-metal-doped BaTiO3-Tb1-xDyxFe2-y bilayer
过渡族元素掺杂BaTiO3-Tb1-xDyxFe2-y层状复合材料中的磁电效应

Cao Hong-Xia,Zhang Ning,
鸿
,张 宁

物理学报 , 2008,
Abstract: 用溶胶-凝胶法制备1.0%mol Mn,Cr,Co掺杂 BaTiO3(BTO)粉体,在1350℃下烧结成多晶陶瓷样品.X射线衍射和差示扫描量热分析表明,室温下掺杂BaTiO3具有四方钙钛矿结构;居里点和相变潜热随Cr,Mn,Co掺杂逐渐降低.将掺杂BaTiO3与Tb1-xDyxFe2-y(TDF)胶合制成双层磁电复合材料,并研究了Cr:BTO-TDF,Mn∶BTO-TDF,Co:BTO-TDF层状复合材料中的磁电效应.实验表明,在340×80 A·m-1偏置磁场下, Cr:BTO-TDF的横向磁电电压系数达到最大值586 mV·cm-1·(80 A·m-1)-1.在400×80 A·m-1偏置磁场下,Mn∶BTO-TDF和Co:BTO-TDF的横向磁电电压系数的最大值分别为480 mV·cm-1·(80 A·m-1)-1和445mV·cm-1·(80 A·m-1)-1.研究表明掺杂BaTiO3-TDF层状复合材料中具有较强的磁电耦合.作为无铅压电材料,掺杂BaTiO3制备的磁电效应器件颇具应用前景.
压电-磁致伸缩双层磁电复合材料的机电谐振
鸿,李敏,张闯,刘清惓,王友保
复合材料学报 , 2013,
Abstract: 基于压电相和磁致伸缩相的本构方程以及弹性体的运动方程,简要推导了一维机电谐振模式下压电-磁致伸缩双层磁电复合材料横向磁电电压系数的表达式。采用相应的材料参数计算分析了Tb1-xDyxFe2-y(TDF)-Pb(Zr,Ti)O3(PZT)双层磁电复合材料的横向磁电电压系数与交流磁场频率的关系,以及复合材料的长度和压电相体积分数对机电谐振频率的影响。计算与分析结果表明,双层磁电复合材料在机电谐振频率处具有明显的磁电响应特性。当有效机械品质因数为50,在谐振频率55.2kHz处横向磁电电压系数达到峰值11.2V·cm-1·Oe-1,是低频下峰值(281.9mV·cm-1·Oe-1)的40倍。机电谐振频率随复合材料长度的减小和压电相体积分数的增加而上升。实验结果说明TDF-PZT双层磁电复合材料在机电谐振频率处具有显著增强的磁电效应,实际有效机械品质因数约为48。
聚氯代对亚苯基二亚甲基的化学气相沉积聚合及表征
鸿,晓星,,杨正龙
华东理工大学学报 , 2006,
Abstract: 用化学气相沉积(CVD)聚合法制备的聚氯代对亚苯基二亚甲基(PPX-C)膜,除了具有聚对亚苯基二亚甲基(PPX)膜的保形涂覆和物理性能外,还具有更好的粘附能力。研究表明:PPX-C膜具有优异的耐溶剂性和抗化学氧化性能;氯的引入使膜的玻璃化转变温度降低,室温柔性增强,动态力学阻尼性能增大,热降解起始温度比PPX膜低,主链降解温度与PPX膜相近。此外,氯的引入对膜的亲水性能影响不大,但膜的水汽渗透率却因此明显降低,与PPX膜相比PPX-C膜具有更好的防潮性能。
葡萄染色体倍性鉴定方法研究进展
Research Progress on Identification Methods of Grape Chromosome Ploidy
 [PDF]

孜义, 陈佰鸿
World Journal of Forestry (WJF) , 2014, DOI: 10.12677/WJF.2014.34010
Abstract:
对葡萄染色体倍性的间接、直接鉴定方法进行了综述,并对各种方法的优越性和不足之处进行了评价。指出葡萄染色体倍性鉴定应因陋就简,早期采用简单鉴定和破坏性较小的鉴定方法,其后用准确的鉴定方法进行综合鉴定。对不同来源的葡萄倍性采用不同的鉴定办法,准确确定倍性为葡萄育种实践服务。
It summarized indirect and direct identification methods of grape chromosome ploidy, and eva-luated that the ploidy identification should be rough. In the early stage, we have to use the simple appraisal method with less destruction. Then, we should use the accurate method to do compre-hensive appraisal, adopting different means for grape ploidy from different sources. Determining the grape ploidy accurately can serve for grape breeding practice.
Chemical composition and magnetism of Ag doped LaMnO3
Zhang Ning,Geng Tao,Cao Hong-Xia,Bao Jian-Chun,
张宁
,耿滔,鸿,包建春

中国物理 B , 2008,
Abstract: By using a sol-gel clue, a set of polycrystalline perovskite samples La粒状系统 复合材料 磁力 Ag LaMnO3granular system, composite, magnetismProject supported by the National Natural Science Foundation of China (Grant Nos 10674071 and 20473038), the Foundation of High-Tech Project in Jiangsu Province, China (Grant No BG-2005041).2005-12-242007-07-09By using a sol-gel clue, a set of polycrystalline perovskite samples La1-xAgxMnO3 with a nominal doping level x ranging from 0.05 to 0.45 has been synthesized. The chemical composition and the magnetism of the samples were investigated. A little Ag was: found seeping from the samples in the sintering process when the doping level exceeded 0.05 and the sintering temperature was higher than 700℃ resulting in the samples being in multiphase. The magnetic transition points of the samples have been found to decrease with increasing sintering temperature. A concentration-dependent Tc similar to that of bivalent metal ion doped perovskite, has been obtained. We believe that the Ag seeping in the sintering process is responsible for those magnetic characteristics.Magnetoeletronic Laboratory, Nanjing Normal University, Nanjing 210097, ChinaLaboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China;University of Shanghai for Science and Technology, Shanghai 200000, China;Magnetoeletronic Laboratory, Nanjing Normal University, Nanjing 210097, ChinaLaboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China;Chemical Department, Nanjing Normal University, Nanjing 210097, ChinaCorresponding author. E-mail: zhangning@njnu.edu.cn/qk/85823A/200801/26433208.html7560J, 8160H, 7550DBy using a sol-gel clue, a set of polycrystalline perovskite samples La粒状系统 复合材料 磁力 Ag LaMnO3granular system, composite, magnetismProject supported by the National Natural Science Foundation of China (Grant Nos 10674071 and 20473038), the Foundation of High-Tech Project in Jiangsu Province, China (Grant No BG-2005041).2005-12-242007-07-09By using a sol-gel clue, a set of polycrystalline perovskite samples La1-xAgxMnO3 with a nominal doping level x ranging from 0.05 to 0.45 has been synthesized. The chemical composition and the magnetism of the samples were investigated. A little Ag was: found seeping from the samples in the sintering process when the doping level exceeded 0.05 and the sintering temperature was higher than 700℃ resulting in the samples being in multiphase. The magnetic transition points of the samples have been found to decrease with increasing sintering temperature. A concentration-dependent Tc similar to that of bivalent metal ion doped perovskite, has been obtained. We believe that the Ag seeping in the sintering process is responsible for those magnetic characteristics.Magnetoeletronic Laboratory, Nanjing Normal University, Nanjing 210097, ChinaLaboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China;University of Shanghai for Science and Technology, Shangha
中外"小矿"法律概念比较研究——写在我国《矿产资源法》修改之际
,
自然资源学报 , 2010, DOI: 10.11849/zrzyxb.2010.08.003
Abstract: ?"小矿"是"小型矿山"的简称,因规模小、投资少、见效快等特点在发展中国家普遍存在,是各国矿业和农村经济的重要组成部分。但同时,它又因浪费资源、破坏环境、安全事故频发等问题而受到国际社会的高度关注。然而,到目前为止,国内外对小矿尚无一个公认的概念。论文基于对现有"小矿"定义以及与小矿相关概念的细致比较,试图给小矿下一个定义,籍此为我国修订中的《矿产资源法》献计献策。笔者以为,小矿是"以谋生或营利为目的,采用简单或基础的采掘设备与技术,在有限的矿藏范围内从事某种矿产品采选活动的小规模、劳动密集型矿山企业。其中包括开采规模达到国家规定的小型矿山标准的小型矿山企业和开采规模在小型矿山上限1/10以下的小矿山企业(含零星个体采矿)。小矿是采矿业最基本的构成部门。"
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