全文获取类型
收费全文 | 1451篇 |
免费 | 9篇 |
国内免费 | 15篇 |
专业分类
电工技术 | 12篇 |
综合类 | 40篇 |
化学工业 | 1034篇 |
金属工艺 | 19篇 |
机械仪表 | 20篇 |
建筑科学 | 74篇 |
矿业工程 | 6篇 |
能源动力 | 12篇 |
轻工业 | 57篇 |
水利工程 | 4篇 |
石油天然气 | 31篇 |
武器工业 | 1篇 |
无线电 | 5篇 |
一般工业技术 | 118篇 |
冶金工业 | 1篇 |
原子能技术 | 31篇 |
自动化技术 | 10篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 8篇 |
2021年 | 21篇 |
2020年 | 31篇 |
2019年 | 13篇 |
2018年 | 15篇 |
2017年 | 20篇 |
2016年 | 9篇 |
2015年 | 24篇 |
2014年 | 60篇 |
2013年 | 162篇 |
2012年 | 76篇 |
2011年 | 109篇 |
2010年 | 89篇 |
2009年 | 90篇 |
2008年 | 80篇 |
2007年 | 70篇 |
2006年 | 63篇 |
2005年 | 68篇 |
2004年 | 64篇 |
2003年 | 72篇 |
2002年 | 47篇 |
2001年 | 41篇 |
2000年 | 56篇 |
1999年 | 55篇 |
1998年 | 25篇 |
1997年 | 14篇 |
1996年 | 17篇 |
1995年 | 16篇 |
1994年 | 13篇 |
1993年 | 10篇 |
1992年 | 15篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 2篇 |
排序方式: 共有1475条查询结果,搜索用时 10 毫秒
81.
82.
相容剂对聚丙烯/滑石粉增容作用研究 总被引:3,自引:0,他引:3
作者采用熔融接技方法制备PP-g-AA和PP-g-MAH,并比较了这两种相容剂对PP/滑石粉体系的增容效果。着重研究了引发剂含量、单体含量对PP-g-AA增容作用的影响以及PP-g-AA用量对PP/滑石粉体系力学强度的影响。 相似文献
83.
《Polymer-Plastics Technology and Engineering》2013,52(3):453-468
Acacia mangiumwood flour (AMWF)–polypropylene (PP) composites were produced at different filler loading (20, 30, 40, and 50 w/w) and mesh no. (35, 60, 80, and 100 mesh). The AMWF–PP composites (using unmodified or modified wood flour) were compounded using a Haake Rheodrive 500 twin screw compounder. The mechanical and water absorption (WA) properties of modified (only at mesh no. 100) and unmodified AMWF–PP composites were investigated. Increase in the mesh number (35–100) of the unmodified AMWF showed increased flexural and impact properties. Flexural modulus exhibited higher properties as the filler loading increased (20–50). However, flexural and impact strength showed the opposite phenomenon. Water absorption and thickness swelling increased as the mesh number and filler loading increased. This has been attributed to the presence of hydrophilic hydroxyl groups of the filler. Modified AMWF–PP composites exhibited higher mechanical properties and good water resistance when compared to unmodified AMWF–PP composites at all values of filler loading. The evidence of the failure mechanism (from impact strength) of the filler–matrix interface was analyzed using scanning electron microscope. 相似文献
84.
85.
86.
The molecular orientation and deformation mechanisms of a quenched isotactic polypropylene (iPP) film deformed at temperatures between 303 K and the melting point are studied. At draw temperature TE less than 400 K where the degree of crystallinity does not change markedly, a linear relationship between molecular orientations of the crystalline and the amorphous phases is revealed and the slope is estimated about 1.82. The interpenetrating network (IPN) model, that takes into account the plastic response of the crystalline (C) network formed by a small portion of crystallites adhered through intercrystalline links and the pseudo-affine deformation of the crystallite enhanced amorphous matrix (CEAM) network, is able to account for inhomogeneous deformation behavior on the mesoscale accompanied with the localized necking in this TE range. Meanwhile, the initial Young's modulus and the true yield stress exerted by the deformation of the rigid C network exhibit the Arrhenius type of dependence on TE. The apparent shear modulus of the CEAM network as a function of TE is discussed in relation to variations in numbers and average molecular weights of the crystalline and the amorphous sequences being manifested by small consecutive endothermic and exothermic peaks in the DSC curve. The IPN model becomes invalid for deformations above TE=400 K where morphological changes are induced due to melting of crystallites as proved from the DSC measurement. 相似文献
87.
常用的几种低热粘结温度柔软型PP短纤维的剖析与研讨 总被引:2,自引:0,他引:2
应用DSC,WAXD,SEM和红外光谱等技术对热轧法生产卫生用薄型非织造布的几种常用纤维进行了剖析,并对其形态结构、热性能、力学性能、含油率、含湿率、抗静电性和渗水性等进行了比较和研讨。结果表明:低热粘结温度PP短纤维多为细旦、低强、高伸度、低起始熔融温度和低序态,且适宜的含油率、含湿率和表面比电阻可保证梳理性好,成网均匀 相似文献
88.
对夏季高温日晒、风吹的施工环境进行了模拟,考察了采取两种养护措施和掺加三种特殊材料对混凝土在此模拟环境下早期收缩性能的影响.通过复掺聚丙烯纤维和膨胀剂,研制了一种在夏季施工环境下10d内几乎不产生收缩的混凝土,并对在夏季环境下混凝土的养护提出了具体的建议. 相似文献
89.
90.
结合工程特点及工艺流程,阐述了300 kt/a聚丙烯装置的布置原则,管道、管架设计要点和方法,以及需要注意的问题。 相似文献