首页 | 官方网站   微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   430篇
  免费   5篇
  国内免费   5篇
工业技术   440篇
  2023年   7篇
  2022年   9篇
  2021年   10篇
  2020年   13篇
  2019年   8篇
  2018年   12篇
  2017年   14篇
  2016年   11篇
  2015年   13篇
  2014年   30篇
  2013年   34篇
  2012年   14篇
  2011年   19篇
  2010年   15篇
  2009年   24篇
  2008年   14篇
  2007年   43篇
  2006年   25篇
  2005年   19篇
  2004年   17篇
  2003年   13篇
  2002年   10篇
  2001年   9篇
  2000年   11篇
  1999年   6篇
  1998年   6篇
  1997年   4篇
  1996年   4篇
  1995年   4篇
  1994年   4篇
  1993年   7篇
  1992年   2篇
  1991年   3篇
  1990年   4篇
  1988年   1篇
  1987年   1篇
排序方式: 共有440条查询结果,搜索用时 15 毫秒
91.
The mechanical integrity of a flexible ZnO-doped In2O3 (IZO)/Ag/IZO multilayer electrode deposited onto a flexible PET substrate using a continuous roll-to-roll (R2R) sputtering system was investigated by means of outer/inner bending, twisting and stretching tests. The R2R-sputtered flexible IZO (40 nm)/Ag (12 nm)/IZO (40 nm) electrode with a sheet resistance of 5.37 Ω/sq and an optical transmittance of 87.3% exhibited superior flexibility due to existence of a ductile Ag layer with high strain failure. It was noteworthy that the failure bending radius (5.5 mm) of the inner bending test was lower than that (6.5 mm) of the outer bending test due to complete separation of the cracks on the top IZO layer during the outer bending test. In addition, the twisting test showed that the resistance of the flexible IZO/Ag/IZO electrode began to increase at an angle of 26°. Furthermore the stretching test demonstrated that the strain failure of the IZO/Ag/IZO multilayer was 2.4%, which is higher than those of conventional flexible ITO electrodes. The mechanical integrity of the R2R-sputtered IZO/Ag/IZO multilayer indicated that hybridization of an oxide and Ag metal is a promising flexible electrode scheme for next generation flexible organic solar cells.  相似文献   
92.
The mechanical flexibility of transparent poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) films printed onto a flexible PET substrate using a gravure printing method was investigated using a lab-made bending test system. Gravure-printed PEDOT:PSS electrodes with a sheet resistance of 359 Ω/square and a transparency of 88.92% showed outstanding flexibility in several types of flexibility tests, including outer/inner bending, twisting and stretching. Notably, the PEDOT:PSS electrode had a constant resistance change (ΔR/R0) within an outer and inner bending radius of 10 mm. In addition the stretched PEDOT:PSS electrode showed a fairly constant resistance change (ΔR/R0) up to 4%, which is more stable than the resistance change of conventional amorphous ITO electrode. The twisting test revealed that the resistance of the PEDOT:PSS electrode began to increase at an angle of 36° due to delamination of the film from the PET substrate. Despite the high sheet resistance of the PEDOT:PSS electrode the flexible organic solar cells fabricated on the PEDOT:PSS electrode showed a power conversion efficiency of ∼2% (FF: 44.9%, Vo: 0.495 V and Jsc: 9.1 mA/cm2), indicating the possibility of using gravure printed PEDOT:PSS as a flexible and transparent electrode for printing-based flexible organic solar cells.  相似文献   
93.
碳纤维复合材料(CFRP)加固混凝土结构是一种新型结构加固方法。在大比例模型试验的基础上,应用有限元程序对 T 型梁进行了加固分析,以研究 CFRP 布加固对混凝土梁抗弯能力及刚度的提高程度。分析结果表明,CFRP 布加固可应用于大型钢筋混凝土桥梁。  相似文献   
94.
冗余度柔性机器人协调操作刚性和柔性负载的仿真分析   总被引:2,自引:0,他引:2  
采用有限元方法建立了冗余度柔性机器人协调操作柔性负载的模型。首次对两4R冗余度柔性机器人协调操作刚性和柔性负载进行了不同目标任务的对比数值仿真分析,指出任务空间和初始角度均是影响系统性能的因素,在设计任务时应选择较好的机器人可操作空间给定任务,使机器人采用较好的初始位形进行运动以提高系统性能。在对系统精度要求较高并且负载与机器人杆件具有接近的尺寸、材料更轻、刚度相近或更小时,需要考虑负载的柔性,以获知精确的负载位姿信息,利用运动补偿等方法消除不利因素,提高系统精度。  相似文献   
95.
2009年,上海能源供应体系自从引入液化天然气以来,进口液化天然气对全市天然气供应总量和来源多元化做出了重要贡献。2013年,液化天然气消费在全市天然气消费总量中占比达50%,在天然气供应体系中发挥了越来越重要的作用。近年来,上海天然气市场发生了深刻变化,天然气需求增长放缓,与2013年之前十多年的两位数增长形成了鲜明对比。为了更好地理解市场的基本面,首先回顾了上海天然气消费的历史趋势,随后分析了影响需求增长的驱动因素和约束条件,以判断未来天然气需求的趋势和液化天然气在市场中扮演的角色,认为天然气需求增长的潜力主要在民用及商业领域。结合分析可能的供应选择,其结论是未来液化天然气将继续作为上海天然气供应体系的主力气源,同时提供市场急需的灵活性以保障高峰时段的用气需求。  相似文献   
96.
Flexibility receives increased interest in chemical engineering and is discussed as one measure to deal with upcoming challenges for the chemical industry. In this paper, different types of flexibility are presented, and flexibility needs are illustrated. The focus is on the evaluation and classification of available solutions to enhance flexibility. Solutions and future challenges across all length scales of chemical engineering are discussed: from tailored catalyst properties to decoupling of processes by means of storage.  相似文献   
97.
针对6R工业机器人,在机器人连杆刚性的假设下,推导了机器人柔度矩阵。分析柔度矩阵将其划分为四个子矩阵:力—位移柔度矩阵、力—角位移柔度矩阵、力矩—位移柔度矩阵、力矩—角位移柔度矩阵。在非奇异位姿下,单独考虑力矢量(或力矩矢量)对末端线位移(或角位移)的影响,研究使末端产生单位变形时需要在末端施加的作用力,提出机器人力—位移、力—角位移、力矩—位移、力矩—角位移‘刚度椭球’,来表述机器人末端的刚度特性,为机器人刚度研究提供了一种新思路。最后以库卡Kr360机器人为例进行计算。计算表明对于Kr360机器人,在末端作用力矢量、力矩矢量在同一数量级时,可忽略力矩矢量对末端的作用效果。  相似文献   
98.
立足于普通建筑院校的实情,借鉴利物浦大学的“双线”体系,提出针对一般建筑院校设计课教学的弹性模式。  相似文献   
99.
本文通过解读近年来医疗建筑界一些重要国际会议的议题和内容,分析当前医院建筑设计创新和研究现状,进而总结出该学术领域内的国际新动向。  相似文献   
100.
A variety of model-based approaches for supporting decision-making under deep uncertainty have been suggested, but they are rarely compared and contrasted. In this paper, we compare Robust Decision-Making with Dynamic Adaptive Policy Pathways. We apply both to a hypothetical case inspired by a river reach in the Rhine Delta of the Netherlands, and compare them with respect to the required tooling, the resulting decision relevant insights, and the resulting plans. The results indicate that the two approaches are complementary. Robust Decision-Making offers insights into conditions under which problems occur, and makes trade-offs transparent. The Dynamic Adaptive Policy Pathways approach emphasizes dynamic adaptation over time, and thus offers a natural way for handling the vulnerabilities identified through Robust Decision-Making. The application also makes clear that the analytical process of Robust Decision-Making is path-dependent and open ended: an analyst has to make many choices, for which Robust Decision-Making offers no direct guidance.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号