Results 41 to 50 of about 15,245 (165)
The investment research on Pinggao Electric CO., Ltd [PDF]
我国证券市场经过20多年的发展,规模不断扩大,市场日趋成熟。截止2014年底,上海和深圳两地上市公司共计2657家,总市值37.25万亿元,年累计成交金额74.23万亿元,已经成为全球第二大证券市场。随着各项创新业务的兴起,特别是融资融券的大力推广,股票期权试点的推出,中国证券市场开始回暖,探底回升,进入全新发展阶段。然而,如何对上市公司的投资价值进行评估,进而对其股价进行估值,得出合理的估值范围,减少投资的盲目性和投机性,正确回避投资风险,依然是投资者十分关心的内容。 本文以上海证券交易所上市公司 ...
吴朝晖
core
Impacts of Human Development on Wildlife Use of Corridors in Botswana 人类开发对博茨瓦纳野生动物廊道利用的影响
This study examined the effect of landscape‐scale human impact on wildlife in Botswana. We examined how species use wildlife corridors in two different human‐dominated landscapes. We identified differences in temporal overlap between wildlife and humans across both landscapes, which is fundamental to consider in both current and future conservation ...
Tempe S. F. Adams +3 more
wiley +1 more source
ABSTRACT The Schottky barrier height (SBH), which serves as a pivotal determinant of charge carrier injection efficiency in electronic devices, critically governs electrical behavior at metal/semiconductor interfaces. However, pronounced metal‐induced gap states at metal contact interfaces induce Fermi‐level pinning, which constrains the ...
Xiaofei Liu +10 more
wiley +1 more source
ABSTRACT In conventional piezoceramics, the coordinated change between the dielectric constant (εr) and the piezoelectric charge constant (d33) usually limits the piezoelectric voltage constant g33 (g33 = d33/εr), a critical figure of merit for piezoelectric sensors.
Xiaoying Feng +7 more
wiley +1 more source
为了确保特高压工程跨电网、跨区域电能计量的准确可靠,促使发电、输电及用电三方的利益得到明确和保证,解决特高压交流电网中电容式电压互感器(CVT)误差特性的现场校准试验难题,研制了一种特高压标准电压互感器一体化装置。基于工频电压加法原理,采用特殊的罐式结构紧凑化设计思路,将特高压电压互感器标准电压互感器设计成上下两级GIS单元,缩小了装置的体积和重量,以适应特高压互感器现场校验车的装载。通过理论计算确定罐体尺寸及材料,使用电磁场仿真软件对隔离互感器进行3D建模及优化设计。样机的测试结果表明 ...
姜春阳 +6 more
doaj
ABSTRACT Emerging as attractive alternatives for sustainable, low‐cost, and high‐performance electromagnetic interference (EMI) shielding, biomass‐derived carbon is nonetheless constrained by a limited repertoire of shielding mechanisms. Herein, a straightforward method was employed to synthesize self‐supporting Co nanoparticles embedded in porous N ...
Yingjie Xu +6 more
wiley +1 more source
前言采用特高压系统输电,已成为大容量电力输送的必然之路。日本特高压输电委员会已经确定,日本特高压输电的额定电压为1000千伏,最大系统电压为1100千伏。在特高压输电系统中,由于系统的操作冲击电压较低,防污设计已成为外绝缘设计的决定因素。因此 ...
尾崎勇造
doaj
Tailoring Spin States of CuNNi3 via d‐d Orbital Coupling for High Performance Water Splitting
ABSTRACT Against the backdrop of escalating global energy crises and environmental challenges, the development of clean and sustainable hydrogen energy has become increasingly imperative. Hydrogen production via water electrolysis is widely regarded as a promising approach due to its green and efficient characteristics.
Weigao Zhong +6 more
wiley +1 more source
回顾总结了国内外的特高压变压器技术现状,介绍了特高压换流变的作用、绝缘结构特点以及换流变的绝缘试验,指出了特高压换流变压器800 kV端绝缘结构耐压水平最高达到1 257 kV以及阀侧套管和出线装置、陡波对绕组纵绝缘的影响和阀侧引出线等绝缘结构薄弱点,为特高压直流换流变的绝缘结构设计制造提供理论依据。
赵鑫 +6 more
doaj
This review summarizes the status of musk deer in China, highlighting severe population declines due to illegal hunting and habitat loss, and proposes integrated conservation strategies including habitat protection, captive breeding, and law enforcement to support the recovery and sustainable management of this ecologically and economically important ...
Feng Jiang +8 more
wiley +1 more source

