全文获取类型
收费全文 | 300篇 |
免费 | 35篇 |
国内免费 | 25篇 |
专业分类
电工技术 | 8篇 |
综合类 | 47篇 |
化学工业 | 63篇 |
金属工艺 | 6篇 |
机械仪表 | 4篇 |
建筑科学 | 144篇 |
矿业工程 | 11篇 |
能源动力 | 1篇 |
轻工业 | 7篇 |
水利工程 | 14篇 |
石油天然气 | 2篇 |
无线电 | 3篇 |
一般工业技术 | 48篇 |
冶金工业 | 2篇 |
出版年
2023年 | 6篇 |
2022年 | 15篇 |
2021年 | 16篇 |
2020年 | 12篇 |
2019年 | 16篇 |
2018年 | 9篇 |
2017年 | 16篇 |
2016年 | 13篇 |
2015年 | 16篇 |
2014年 | 10篇 |
2013年 | 33篇 |
2012年 | 22篇 |
2011年 | 17篇 |
2010年 | 19篇 |
2009年 | 20篇 |
2008年 | 12篇 |
2007年 | 14篇 |
2006年 | 20篇 |
2005年 | 16篇 |
2004年 | 8篇 |
2003年 | 11篇 |
2002年 | 5篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 4篇 |
1995年 | 4篇 |
1994年 | 5篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1989年 | 2篇 |
1980年 | 1篇 |
排序方式: 共有360条查询结果,搜索用时 15 毫秒
1.
Analyses of the practical adhesion strengths of the metal/polymer interfaces in electronic packaging
There is a plethora of techniques to measure the adhesion strength of metal/polymer interfaces. However, the practical adhesion
strength, which is the work done in separating the film from the substrate (or one film from another), is very sensitive to
the test methods and the mechanical effects, such as the residual stress, thickness and mechanical properties of the layers,
strain rate, and phase angle. Deriving intrinsic-adhesion properties of the interfaces, which are independent of such parameters,
from the practical adhesion-strength measurements is a formidable task. In the present work, data from the three commonly
used adhesion tests; pull-out, 90°-peel, and T-peel tests are compared with the intrinsic-adhesion properties of the interface,
such as the interface-fracture toughness or the interface-fracture energy, and their implications are discussed. Material
systems analyzed were Cu-based lead frame/epoxy-molding compound (EMC) and Cu/Cr/polyimide. 相似文献
2.
Theoretical analyses for the single fibre pull-out and push-out models under monotonic loading are given which are based on a shear-lag analysis in a fracture mechanics approach considering non-constant friction at the debonded interface as a result of fibre Poisson contraction (or expansion). The solutions allow the determination of typical fibre/matrix interfacial properties such as the interfacial fracture toughness, Gic, the coefficient of friction, μ, and the residual clamping stress, q0. Under cyclic loading the interfacial properties are expected to degrade as a result of repetitive abrasion, and a power law function is assumed between μ and the number of elapsed cycles, N. However, Gic is assumed to be unaffected and a fracture mechanics based debond criterion is derived for the relationship between the external applied stress, the debond length and the reduced friction coefficient for both fibre pull-out and fibre push-out. In addition, the relative displacements between the free fibre end and the matrix top are obtained for cyclic fatigue when the fibre is loaded and unloaded. A relationship obtained for the protrusion (or intrusion) length in fibre pull-out (or push-out) experiments allows the severity of the interface frictional degradation to be evaluated and characterised. Similarities and differences in the frictional degradation behaviour between fibre pull-out and push-out are also identified. 相似文献
3.
采空区治理工程中注浆管的起拔及重复利用 总被引:1,自引:1,他引:0
以某采空区治理工程为例,介绍了采用正反丝连接注浆管的新方法,成功地解决了注浆管的起拔及重复利用问题,并对新法与不拔管及常规拔管方法的经济性进行了分析比较。 相似文献
4.
采用高密度聚乙烯(HDPE)单向土工格栅与聚脂(PET)双向土工格栅,以及南水北调中线工程新乡段的膨胀性泥灰岩风化土,在填土尺寸为600 mm×600 mm×600 mm的大型叠环式剪切仪上进行拉拔试验,研究了干密度对土工格栅与膨胀土界面拉拔性状的影响.结果表明:干密度较大时,土工格栅刚体平动及其速率增大时的拉拔力较大,峰值拉拔力较大,峰值时土工格栅的变形量较大;干密度较大时,筋土界面摩阻力-相对位移曲线更偏于弹塑性特征,其界面切向刚度较小;干密度对界面似摩擦角的影响显著,而对似粘聚力的影响较小. 相似文献
5.
M. Sharan Chandran K. Padmanabhan D. K. Dipin Raj Yashasvi Chebiyyam 《Journal of Adhesion Science and Technology》2020,34(5):511-530
AbstractInterfacial adhesion of composite materials plays an important role in their mechanical properties and performance. In the present investigation, analysis of the interfacial properties of self-reinforced polyamide composites by using microbond multiple fibre pull-out test is emphasised. Microbond specimens prepared through thermal processing are tested for their interfacial properties by multiple fibre bundle pull-out tests and compared with that of traditional single fibre pull-out test specimens. Multiple fibre pull-out addresses the volume fraction as well as eliminates the possibility of fibre breakage before matrix shear. Higher scatter in the data in the samples is addressed in the present studies. FTIR and Fractographic studies are carried out for deep understanding of the post pull-out interfacial adhesion. 相似文献
6.
7.
Sang-Soo Jeon 《中南工业大学学报(英文版)》2012,19(1):262-272
The pull-out capacities for soil nailing systems comprising of one single 29 mm diameter (type A) and four 16 mm diameter
(type B) rebars with grouted cement were examined. A field test and numerical analysis for the type A and type B systems were
carried out to investigate the pull-out capacities and the slope stability reinforcement efficiency in soil and rock slopes.
The results of the pull-out tests show the mobilized shear force and load transfer characteristics with respect to soil depth.
The load-displacement relationship was examined for both type A and type B systems. Slope stability analyses were carried
out to study the relationships between soil and nail reinforcement and bending stiffness as well as combined axial tension
and shear forces. Factors of safety were calculated in relation to the number of nails and their outside diameters. Both soil
and rock slopes were included in this evaluation. 相似文献
8.
水泥基无机黏结材料植筋承载力的试验研究 总被引:1,自引:0,他引:1
通过对水泥基无机黏结材料植筋承载力的拉拔试验研究,分析了水泥基无机黏结材料植筋的破坏形态和破坏机理,讨论并给出了极限锚固承载力计算公式及建议施工锚固长度表格.通过与同条件下预埋钢筋、植筋后绑焊以及某有机黏结材料植筋承载力相比得到此水泥基无机黏结材料的工程适用性,并在实际工程中得到验证. 相似文献
9.
为了正确地选用步进电动机的驱动单元,采用分布非线性磁网络模型对电感进行准确计算,给出了步进电动机输出最大可用功率与一些参数的关系。理论分析和实验研究表明,步进电动机最大可用功率主要取决于电动机的综合参数和配套驱动器的功放级电压,从而较好地解决了步进电动机的选择中概念模糊的问题。 相似文献
10.
从能量原理出发,把钢筋混凝土看成为一种纤维增强复合材料,利用已有的实验回归公式,推导出了钢筋混凝土中钢筋与混凝土的脱开条件,给出了钢筋的拔出长度与拔出载荷的关系。 相似文献