全文获取类型
收费全文 | 427篇 |
免费 | 18篇 |
专业分类
电工技术 | 3篇 |
综合类 | 1篇 |
化学工业 | 99篇 |
金属工艺 | 5篇 |
机械仪表 | 9篇 |
建筑科学 | 19篇 |
能源动力 | 6篇 |
轻工业 | 54篇 |
水利工程 | 6篇 |
无线电 | 17篇 |
一般工业技术 | 61篇 |
冶金工业 | 80篇 |
原子能技术 | 1篇 |
自动化技术 | 84篇 |
出版年
2024年 | 3篇 |
2023年 | 4篇 |
2022年 | 30篇 |
2021年 | 32篇 |
2020年 | 12篇 |
2019年 | 13篇 |
2018年 | 7篇 |
2017年 | 5篇 |
2016年 | 13篇 |
2015年 | 10篇 |
2014年 | 14篇 |
2013年 | 24篇 |
2012年 | 23篇 |
2011年 | 20篇 |
2010年 | 11篇 |
2009年 | 15篇 |
2008年 | 10篇 |
2007年 | 17篇 |
2006年 | 10篇 |
2005年 | 16篇 |
2004年 | 9篇 |
2003年 | 4篇 |
2002年 | 8篇 |
2001年 | 9篇 |
2000年 | 8篇 |
1999年 | 7篇 |
1998年 | 23篇 |
1997年 | 12篇 |
1996年 | 7篇 |
1995年 | 7篇 |
1994年 | 12篇 |
1993年 | 5篇 |
1991年 | 4篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 6篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1971年 | 1篇 |
1969年 | 1篇 |
1960年 | 1篇 |
1951年 | 1篇 |
排序方式: 共有445条查询结果,搜索用时 15 毫秒
1.
Pasquale Stano Tereza Pereira de Souza Paolo Carrara Emiliano Altamura Erica D’Aguanno Margherita Caputo 《先进材料力学与结构力学》2015,22(9):748-759
Here we report some recent biophysical issues on the preparation of solute-filled lipid vesicles and their relevance to the construction of “synthetic cells.” First, we introduce the “semi-synthetic minimal cells” as the liposome-based cell-like systems, which contain a minimal number of biomolecules required to display simple and complex biological functions. Next, we focus on recent aspects related to the construction of synthetic cells. Emphasis is given to the interplay between the methods of synthetic cell preparation and the physics of solute encapsulation. We briefly introduce the notion of structural and compositional “diversity” in synthetic cell populations. 相似文献
2.
Spectrum asked three IEEE members from the telecommunications sector to comment on the industry's current woes and prospects. Roch Guerin discusses bandwidth as a commodity and how to deal with it. The impact of technological change on telecommunications is enormous and calls for a shift in business models. Technology is making bandwidth a commodity and it should not matter who supplies it. Competition is vital and commodity providers must be decoupled from value providers. Frank Ferrante points out that the Year 2000 crisis resulted in manufacturers being deluged with orders for new upgraded systems. Vast sums were spent to meet the demand in time. However, when Y2K was over, production stayed high and inventories continued to build, while demand effectively stopped overnight. Dazzling new innovations are needed to compel the masses to spend and manufacturers must apply their resources to deliver quickly and efficiently. Jules A. Bellisio discusses the role of engineers in bringing new ideas to the market place. Many engineers have put together ventures for the sole purpose of attracting capital. The underlying technology and business propositions were there solely to lure the unsuspecting. By allowing engineers to use technology simply to cover for a scam, then the profession is also to blame for the current problems. 相似文献
3.
4.
5.
6.
As software and hardware evolve, licensing choices are becoming more complex. Understanding licensing trends and the latest models is one way to achieve the greatest return on software investment. 相似文献
7.
DellaGreca M Isidori M Lavorgna M Monaco P Previtera L Zarrelli A 《Journal of chemical ecology》2004,30(4):867-879
Twenty-five 9,10-dihydrophenanthrenes, four phenanthrenes, a dihydrodibenzoxepin, and a pyrene, isolated from the wetland plant Juncus acutus, were tested to detect their effects on the green alga Selenastrum capricornutum. Nine of the compounds were isolated and identified for the first time. Most of the compounds caused inhibition of algal growth. The 9,10-dihydrophenanthrenes 1, 5, 21, and 22 were the most active. 相似文献
8.
9.
Jepsen T.C. Laplante P.A. Williams J. Christensen K. Ferrante D. Chang J.M. Miller G. 《IT Professional》2004,6(4):10-17
What will software look like in the future? To answer this question, we conducted a survey of our editorial and industrial advisory boards, as well as a few outsiders. We constructed a set of 13 questions that we thought reflected the original query. We then circulated these questions to our boards, with a request to respond to the questions, or be extend them with additional are questions as appropriate. The answers were far ranging and sometimes surprising. 相似文献
10.
In this paper we investigate on the existence of the stabilizing solution of the algebraic Riccati equation (ARE) related to the
filtering problem with a prescribed attenuation level γ. It is well known that such a solution exists and is positive definite for γ larger than a certain γF and it does not exist for γ smaller than a certain γ0. We consider the intermediate case γ(γ0,γF] and show that in this interval the stabilizing solution does exist, except for a finite number of values of γ. We show how the solution of the ARE may be employed to obtain a minimum-phase J-spectral factor of the J-spectrum associated with the
filtering problem. 相似文献