全文获取类型
收费全文 | 278篇 |
免费 | 14篇 |
专业分类
电工技术 | 6篇 |
化学工业 | 71篇 |
金属工艺 | 2篇 |
机械仪表 | 2篇 |
建筑科学 | 17篇 |
矿业工程 | 1篇 |
能源动力 | 4篇 |
轻工业 | 39篇 |
水利工程 | 3篇 |
无线电 | 14篇 |
一般工业技术 | 23篇 |
冶金工业 | 29篇 |
原子能技术 | 2篇 |
自动化技术 | 79篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 5篇 |
2021年 | 10篇 |
2020年 | 2篇 |
2019年 | 8篇 |
2018年 | 4篇 |
2017年 | 6篇 |
2016年 | 9篇 |
2015年 | 9篇 |
2014年 | 12篇 |
2013年 | 8篇 |
2012年 | 11篇 |
2011年 | 21篇 |
2010年 | 11篇 |
2009年 | 15篇 |
2008年 | 14篇 |
2007年 | 18篇 |
2006年 | 12篇 |
2005年 | 10篇 |
2004年 | 21篇 |
2003年 | 15篇 |
2002年 | 13篇 |
2001年 | 3篇 |
2000年 | 9篇 |
1999年 | 13篇 |
1998年 | 4篇 |
1997年 | 5篇 |
1996年 | 1篇 |
1995年 | 4篇 |
1994年 | 3篇 |
1993年 | 4篇 |
1991年 | 2篇 |
1988年 | 1篇 |
1986年 | 2篇 |
1982年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有292条查询结果,搜索用时 46 毫秒
141.
David Sullivan Patricia Hooks Michael Mier Jaap W. van Hal Xiankuan Zhang 《Topics in Catalysis》2006,38(4):303-308
The effect of catalyst support and preparation method on silver-based catalysts for the direct vapor phase epoxidation of
propylene to propylene oxide (PO) was studied. The shape of the CaCO3 support is critical for optimum activity and selectivity of the catalyst. Among the CaCO3 materials investigated as supports, the scalenohedral shape gives the best performance. A simplified method of catalyst preparation
(referred to as “slurry method”) was developed. With this method, it is not necessary to dissolve Ag2O into a solution as in the conventional incipient wetness method for preparing silver-based catalysts for propylene and ethylene
epoxidation. The key to the slurry method is the addition of a small amount of an effective organic compound, such as ethanolamine,
during the formation of the slurry. 相似文献
142.
143.
144.
Janine Reurink Adrian Dockery Dominika Ozibo G. Jane Farrar Monika Odak Jacoline B. ten Brink Arthur A. Bergen Tuula Rinne Helger G. Yntema Ronald J. E. Pennings L. Ingeborgh van den Born Marco Aben Jaap Oostrik Hanka Venselaar Astrid S. Plomp M. Imran Khan Erwin van Wijk Frans P. M. Cremers Susanne Roosing Hannie Kremer 《International journal of molecular sciences》2021,22(12)
A substantial proportion of subjects with autosomal recessive retinitis pigmentosa (arRP) or Usher syndrome type II (USH2) lacks a genetic diagnosis due to incomplete USH2A screening in the early days of genetic testing. These cases lack eligibility for optimal genetic counseling and future therapy. USH2A defects are the most frequent cause of USH2 and are also causative in individuals with arRP. Therefore, USH2A is an important target for genetic screening. The aim of this study was to assess unscreened or incompletely screened and unexplained USH2 and arRP cases for (likely) pathogenic USH2A variants. Molecular inversion probe (MIP)-based sequencing was performed for the USH2A exons and their flanking regions, as well as published deep-intronic variants. This was done to identify single nucleotide variants (SNVs) and copy number variants (CNVs) in 29 unscreened or partially pre-screened USH2 and 11 partially pre-screened arRP subjects. In 29 out of these 40 cases, two (likely) pathogenic variants were successfully identified. Four of the identified SNVs and one CNV were novel. One previously identified synonymous variant was demonstrated to affect pre-mRNA splicing. In conclusion, genetic diagnoses were obtained for a majority of cases, which confirms that MIP-based sequencing is an effective screening tool for USH2A. Seven unexplained cases were selected for future analysis with whole genome sequencing. 相似文献
145.
Claudine Moratal Audrey Laurain Mourad Naïmi Thibault Florin Vincent Esnault Jaap G. Neels Nicolas Chevalier Giulia Chinetti Guillaume Favre 《International journal of molecular sciences》2021,22(11)
Diabetic nephropathy (DN) is characterized by albuminuria, loss of renal function, renal fibrosis and infiltration of macrophages originating from peripheral monocytes inside kidneys. DN is also associated with intrarenal overactivation of the renin–angiotensin system (RAS), an enzymatic cascade which is expressed and controlled at the cell and/or tissue levels. All members of the RAS are present in the kidneys and most of them are also expressed in monocytes/macrophages. This review focuses on the control of monocyte recruitment and the modulation of macrophage polarization by the RAS in the context of DN. The local RAS favors the adhesion of monocytes on renal endothelial cells and increases the production of monocyte chemotactic protein-1 and of osteopontin in tubular cells, driving monocytes into the kidneys. There, proinflammatory cytokines and the RAS promote the differentiation of macrophages into the M1 proinflammatory phenotype, largely contributing to renal lesions of DN. Finally, resolution of the inflammatory process is associated with a phenotype switch of macrophages into the M2 anti-inflammatory subset, which protects against DN. The pharmacologic interruption of the RAS reduces albuminuria, improves the trajectory of the renal function, decreases macrophage infiltration in the kidneys and promotes the switch of the macrophage phenotype from M1 to M2. 相似文献
146.
This paper considers the significance of organic food production in the Netherlands. It critically examines the social and political construction of food markets in the context of the dominance of industrial and corporate retailer‐led food supply chains. Two cases are used to illustrate counter or alternative trends: Frisian Organic Dairy Products (FEZ) and the case of Jan Fokke, a producer converting to organic production. Some key elements of actor‐network theory are developed which focus attention upon the social capabilities and incapacities involved in this transition. The paper highlights some of the inherently strong features of alternative food supply chains and networks, arguing for an expanded definition of ‘organic’ production as a form of social as well as technical organization. 相似文献
147.
148.
149.
Tao Cai Jaap van de Beek Jad Nasreddine Marina Petrova Petri Mähönen 《International Journal of Wireless Information Networks》2011,18(3):131-145
In this article we describe a demonstrator that shows how the cognitive resource manager (CRM) and the radio-environmental
map (REM) can be efficiently implemented in full commercial grade cellular system (i.e., LTE system). The demonstrator shows
how the modular CRM together with its open interface, the universal link-layer API (ULLA), facilitates the implementation
of efficient radio resource management techniques guaranteeing the quality of service in the LTE system. The CRM, through
ULLA, is able to obtain PHY/MAC status information of the link between the tested eNode B and the user equipment, and reconfigure
link parameters. This measure-and-control by CRM/ULLA is independent of the underlying radio access technology, which shows
the neutrality of CRM/ULLA towards PHY/MAC characteristics. The article also shows how the REM can be easily implemented in
such system and how the REM provides the CRM with environmental information that enhances system management performance. 相似文献
150.
Jurgen H. Runge Pieter J. Bakker Ingrid C. Gaemers Joanne Verheij Theo B. M. Hakvoort Roelof Ottenhoff Aart J. Nederveen Jaap Stoker 《Magma (New York, N.Y.)》2014,27(4):317-327