全文获取类型
收费全文 | 940篇 |
免费 | 113篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 14篇 |
综合类 | 22篇 |
化学工业 | 833篇 |
金属工艺 | 4篇 |
机械仪表 | 10篇 |
建筑科学 | 43篇 |
矿业工程 | 1篇 |
能源动力 | 6篇 |
水利工程 | 2篇 |
石油天然气 | 9篇 |
武器工业 | 4篇 |
无线电 | 1篇 |
一般工业技术 | 92篇 |
冶金工业 | 5篇 |
原子能技术 | 9篇 |
自动化技术 | 1篇 |
出版年
2024年 | 4篇 |
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 22篇 |
2020年 | 8篇 |
2019年 | 7篇 |
2018年 | 21篇 |
2017年 | 15篇 |
2016年 | 10篇 |
2015年 | 10篇 |
2014年 | 30篇 |
2013年 | 72篇 |
2012年 | 45篇 |
2011年 | 75篇 |
2010年 | 43篇 |
2009年 | 55篇 |
2008年 | 58篇 |
2007年 | 51篇 |
2006年 | 57篇 |
2005年 | 47篇 |
2004年 | 48篇 |
2003年 | 51篇 |
2002年 | 57篇 |
2001年 | 42篇 |
2000年 | 46篇 |
1999年 | 54篇 |
1998年 | 41篇 |
1997年 | 19篇 |
1996年 | 16篇 |
1995年 | 13篇 |
1994年 | 8篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1984年 | 1篇 |
排序方式: 共有1056条查询结果,搜索用时 15 毫秒
1.
橡胶卷材挤出连续硫化生产线的结构特色与工作原理 总被引:1,自引:0,他引:1
介绍了橡胶防水防腐卷材挤出连续硫化生产线的结构、特点和工作原理;指出在目前国内同类设备中,该生产设备具有先进性,并可替代引进设备。 相似文献
2.
Dynamic vulcanisation of EPDM/PE-based thermoplastic vulcanisates studied along the extruder axis 总被引:1,自引:0,他引:1
Simple blending and dynamic vulcanisation of EPDM/PE blends using the resol/SnCl2 system was studied in an extruder using a series of sampling devices. The melting of the PE pellets occurs just in front of and in the first kneading zone. Upon complete melting of the PE phase, the EPDM/PE blends reach very quickly their final morphology. Crosslinking of the EPDM phase to high levels occurs already when the PE phase is not yet fully molten. The higher the EPDM content, the higher the viscous dissipation, the higher the melt temperature and, consequently, the higher the crosslinking rate. For the EPDM/PE (50/50; w/w) TPV a transition from continuous via co-continuous to fully dispersed EPDM is observed, which is driven by crosslinking. Although the degree of crosslinking of the EPDM rubber is very high, this does not prevent phase inversion of the blend. The EPDM/PE interface is rather blurred, because PE crystalline lamellae are growing into the EPDM domains, probably because of the high compatibility between PE and EPDM (60 wt% of ethene). This study shows that dynamic vulcanisation in extruders proceeds quite differently from that in batch kneaders, where melting, mixing and crosslinking are separated in time. In extruders mass and heat transport, melting of the thermoplastic, morphology development (including dispersion and phase inversion), distribution and dissolution of (crosslinking) chemicals and crosslinking of the rubber do not occur as independent phenomena, but mutually and/or continuously interact. 相似文献
3.
In the research presented here, we explore the use of a low‐energy plasma to deposit thin silicone polymer films using tetramethyldisiloxane (TMDSO) (H(CH3)2? Si? O? Si? (CH3)2H) on the surface of an ethylene propylene diene elastomeric terpolymer (EPDM) in order to enhance the surface hydrophobicity, lower the surface energy and improve the degradation/wear characteristics. The processing conditions were varied over a wide range of treatment times and discharge powers to control the physical characteristics, thickness, morphology and chemical structure of the plasma polymer films. Scanning electron microscopy (SEM) shows that pore‐free homogeneous plasma polymer thin films of granular microstructure composed of small grains are formed and that the morphology of the granular structure depends on the plasma processing conditions, such as plasma power and time of deposition. The thicknesses of the coatings were determined using SEM, which confirmed that the thicknesses of the deposited plasma‐polymer films could be precisely controlled by the plasma parameters. The kinetics of plasma‐polymer film deposition were also evaluated. Contact angle measurements of different solvent droplets on the coatings were used to calculate the surface energies of the coatings. These coatings appeared to be hydrophobic and had low surface energies. X‐ray photoelectron spectroscopy (XPS) and photoacoustic Fourier‐transform infrared (PA‐FT‐IR) spectroscopy were used to investigate the detailed chemical structures of the deposited films. The optimum plasma processing conditions to achieve the desired thin plasma polymer coatings are discussed in the light of the chemistry that takes place at the interfaces. Copyright © 2004 Society of Chemical Industry 相似文献
4.
5.
6.
Canchen Sun Yuanyuan Wang Bin Wang Yanxia Cao Jianfeng Wang Yanyu Yang Wanjie Wang 《大分子材料与工程》2021,306(5):2000813
Here, zinc-neutralized ethylene propylene diene monomer (EPDM) ionomers with different neutralization levels are prepared through melt blending, and are then incorporated with polyamide 1012 (PA1012) to fabricate PA1012/EPDM ionomer blends. Interestingly, complex crosslinking networks are formed in the blends due to the construction of sacrificial bonds (Zn2+-carboxyl, Zn2+-amide). The as-formed network structure and sacrificial bond endow the PA/EPDM blends with largely enhanced toughness (16 times higher than that of neat PA), as well as balanced strength and stiffness. Meanwhile, the rheological behaviors of PA1012/EPDM ionomer blends indicate their relative low melting viscosity, which can avoid the processing shortcomings of plastics toughened with rubber. Moreover, PA1012/EPDM ionomer blends show obvious gelation behavior, and a maximum notched Izod impact strength exhibited at the gel point, in which unique double network structure can be observed obviously, indicating that there is a corresponding correlation between the rheological and mechanical parameters. Furthermore, the supper-toughening mechanism of PA1012/EPDM ionomer blends at gel point is explored, which origins from the large deformation and cavitation of rubber particles and the destruction of special double network morphologies. This study provides a novel and effective strategy to fabricate PA materials with outstanding toughness and excellent strength simultaneously. 相似文献
7.
介绍了FR-1型粘合剂用于氟橡胶、硅橡胶、三元乙丙橡胶与金属热硫化粘着,制作橡胶金属复合制品的情况。金属骨架经喷砂或表面化学处理并用溶剂清洗之后,涂FR—1型粘合剂,经预烘干后与橡胶进行热硫化粘着,效果良好。 相似文献
8.
9.
NBR/EPDM的增容共混研究 总被引:4,自引:1,他引:4
本文采用第三组份增容途径,改善了NBR/EPDM并用胶的相容性、加工性和力学性能。通过对不同增容体系的研究对比,发现不同增容剂的增容效果差异很大,其巾以EVA-14增容效果最为显著,加入该增容剂的并用胶,在适当的工艺条件及硫化体系下,可获得最佳力学性能。本文还研究了不同增容剂对并用炭黑胶各种性能的影响,可以做到在不降低并用胶的力学性能的同时,提高并用胶的耐热空气老化、耐大气老化和耐臭氧老化性能.透射电镜实验和动态力学谱图证明了加与未加增容剂时,NBR/EPDM并用胶均为两相结构,增容剂起表面活性剂的作用,加强了两相界面间的相互作用,使分散相EPDM细微化和均匀化。 相似文献
10.
橡胶/蒙脱土纳米复合材料的优异性能使其成为橡胶工业中富有潜力的一类新型材料。笔者综述了三元乙丙橡胶(EPDM)/蒙脱土纳米复合材料的制备方法、性能和工业应用领域等,讨论了蒙脱土片层的表面修饰、插层剂的选择以及复合材料的制备方法对材料性能的影响,并提出了三元乙丙橡胶/蒙脱土纳米复合材料这一新型橡胶材料在轮胎工业上的应用前景。 相似文献