全文获取类型
收费全文 | 886篇 |
免费 | 59篇 |
国内免费 | 4篇 |
学科分类
工业技术 | 949篇 |
出版年
2024年 | 2篇 |
2023年 | 16篇 |
2022年 | 15篇 |
2021年 | 40篇 |
2020年 | 37篇 |
2019年 | 27篇 |
2018年 | 43篇 |
2017年 | 45篇 |
2016年 | 41篇 |
2015年 | 26篇 |
2014年 | 44篇 |
2013年 | 87篇 |
2012年 | 44篇 |
2011年 | 50篇 |
2010年 | 44篇 |
2009年 | 33篇 |
2008年 | 43篇 |
2007年 | 32篇 |
2006年 | 35篇 |
2005年 | 28篇 |
2004年 | 19篇 |
2003年 | 12篇 |
2002年 | 11篇 |
2001年 | 13篇 |
2000年 | 8篇 |
1999年 | 3篇 |
1998年 | 21篇 |
1997年 | 11篇 |
1996年 | 10篇 |
1995年 | 11篇 |
1994年 | 7篇 |
1993年 | 11篇 |
1992年 | 10篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 8篇 |
1988年 | 6篇 |
1987年 | 10篇 |
1986年 | 9篇 |
1985年 | 6篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 5篇 |
1977年 | 6篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1970年 | 2篇 |
排序方式: 共有949条查询结果,搜索用时 441 毫秒
1.
Sustainable biocomposites have gained considerable interest as an alternative to conventional composites in recent years due to their cost-effectiveness and environmental friendliness. The aim of this study was to investigate the performance and durability behavior of biocomposites from sustainable biocarbon (BC) as compared to conventional established fillers. The poly(butylene terephthalate) (PBT) and its composites reinforced with BC, talc, and glass fiber (GF) were prepared and the durability performances was investigated. The study showed that BC/PBT biocomposites provided a lighter weight alternative to traditionally used fillers. After undergoes thermo-oxidative aging, the mechanical properties of BC/PBT biocomposite were deteriorated. The GF/PBT showed the most stable in retaining its mechanical properties in comparison to the talc/PBT and BC/PBT. The aging behavior and mechanism of the PBT composites were discussed. This study provides further insight on the durability-related properties progression of biocomposites as compared to traditional used fillers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47722. 相似文献
2.
Hyungson Ki Jyoti Mazumder Pravansu S. Mohanty 《Metallurgical and Materials Transactions A》2002,33(6):1817-1830
A three-dimensional laser-keyhole welding model is developed, featuring the self-consistent evolution of the liquid/vapor
(L/V) interface together with full simulation of fluid flow and heat transfer. Important interfacial phenomena, such as free
surface evolution, evaporation, kinetic Knudsen layer, homogeneous boiling, and multiple reflections, are considered and applied
to the model. The level set approach is adopted to incorporate the L/V interface boundary conditions in the Navier-Stokes
equation and energy equation. Both thermocapillary force and recoil pressure, which are the major driving forces for the melt
flow, are incorporated in the formulation. For melting and solidification processes at the solid/liquid (S/L) interface, the
mixture continuum model has been employed. The article consists of two parts. This article (Part I) presents the model formulation
and discusses the effects of evaporation, free surface evolution, and multiple reflections on a steady molten pool to demonstrate
the relevance of these interfacial phenomena. The results of the full keyhole simulation and the experimental verification
will be provided in the companion article (Part II). 相似文献
3.
4.
5.
6.
7.
8.
9.
S. Sarkar P. K. Singha S. Dey M. Mohanty B. Adhikari 《Materials and Manufacturing Processes》2006,21(3):291-296
A polyester urethane was synthesized for use in a biodegradable scaffold. The polyurethane was synthesized in a two-step process: first, ester diol was synthesized from lactic acid and polyethylene glycol 400 (PEG 400), then it was polymerized with toluene diisocyanate using dibutyl tin dilaurate (DBTDL) as a catalyst to form a polyester urethane. Polyester urethane has tensile strength of 51-59 MPa and elongation at fracture of 369-439%. FTIR and XRD were used to confirm the formation and structure of the polymer. Hydrolytic degradation was studied in different alkali solutions and in saline water. In order to assess the cellular response of this material, cytotoxicity analysis was carried out against the cell line. 相似文献
10.
Engineering with Computers - We studied a new implicit method of order three based on two off-step points for the numerical solution of second-order nonlinear initial-value problems... 相似文献