全文获取类型
收费全文 | 435篇 |
免费 | 40篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 104篇 |
金属工艺 | 7篇 |
机械仪表 | 8篇 |
建筑科学 | 10篇 |
矿业工程 | 1篇 |
能源动力 | 6篇 |
轻工业 | 24篇 |
水利工程 | 8篇 |
石油天然气 | 2篇 |
无线电 | 31篇 |
一般工业技术 | 139篇 |
冶金工业 | 62篇 |
原子能技术 | 1篇 |
自动化技术 | 70篇 |
出版年
2023年 | 10篇 |
2022年 | 10篇 |
2021年 | 30篇 |
2020年 | 18篇 |
2019年 | 24篇 |
2018年 | 21篇 |
2017年 | 14篇 |
2016年 | 24篇 |
2015年 | 13篇 |
2014年 | 23篇 |
2013年 | 29篇 |
2012年 | 25篇 |
2011年 | 45篇 |
2010年 | 26篇 |
2009年 | 17篇 |
2008年 | 20篇 |
2007年 | 15篇 |
2006年 | 22篇 |
2005年 | 16篇 |
2004年 | 9篇 |
2003年 | 6篇 |
2002年 | 5篇 |
2001年 | 7篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 9篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1984年 | 2篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 3篇 |
1973年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有475条查询结果,搜索用时 0 毫秒
471.
Filipa Mota Tamas Yelland Jennie A. Hutton Jennifer Parker Anastasia Patsiarika A. W. Edith Chan Andrew O'Leary Constantina Fotinou John F. Martin Ian C. Zachary Snezana Djordjevic Paul Frankel David L. Selwood 《Chembiochem : a European journal of chemical biology》2022,23(1):e202100463
Vascular endothelial growth factors (VEGFs) regulate significant pathways in angiogenesis, myocardial and neuronal protection, metabolism, and cancer progression. The VEGF-B growth factor is involved in cell survival, anti-apoptotic and antioxidant mechanisms, through binding to VEGF receptor 1 and neuropilin-1 (NRP1). We employed surface plasmon resonance technology and X-ray crystallography to analyse the molecular basis of the interaction between VEGF-B and the b1 domain of NRP1, and developed VEGF-B C-terminus derived peptides to be used as chemical tools for studying VEGF-B - NRP1 related pathways. Peptide lipidation was used as a means to stabilise the peptides. VEGF-B-derived peptides containing a C-terminal arginine show potent binding to NRP1-b1. Peptide lipidation increased binding residence time and improved plasma stability. A crystal structure of a peptide with NRP1 demonstrated that VEGF-B peptides bind at the canonical C-terminal arginine binding site. VEGF-B C-terminus imparts higher affinity for NRP1 than the corresponding VEGF-A165 region. This tight binding may impact on the activity and selectivity of the full-length protein. The VEGF-B167 derived peptides were more effective than VEGF-A165 peptides in blocking functional phosphorylation events. Blockers of VEGF-B function have potential applications in diabetes and non-alcoholic fatty liver disease. 相似文献
472.
Yadong Zhang Dragos SegheteAziz Abdulagatov Zachary GibbsAndrew Cavanagh Ronggui YangSteven George Yung-Cheng Lee 《Surface & coatings technology》2011,205(10):3334-3339
The film perfection in terms of pinhole defect densities of ultra-thin Al2O3 grown by atomic layer deposition (ALD) has been quantitatively characterized. A significant defect density reduction from ~ 1.2 × 105/cm2 to ~ 90/cm2 was demonstrated for 2 nm-thick Al2O3 by using an ALD tungsten (W) buffer layer on the nickel (Ni) substrate. The reason for the defect reduction was attributed to efficient nucleation of ALD Al2O3 on ALD W. The effect of the buffer layer becomes less essential as the Al2O3 thickness increases, where the substrate surface physical conditions such as particle contamination become the main cause for defects. 相似文献
473.
Zachary N. Wing Brian Wang John W. Halloran 《Journal of the American Ceramic Society》2006,89(12):3696-3700
Relative permittivities ranging from 12 to 100 were obtained from porous titania. Relative permittivities from 8 to 30 were obtained from porous calcium magnesium titanates. Porosity was introduced as microporosity by partial sintering, as 15 μm diameter spherical pores with porogens, and by fabrication of a microcellular structure with cylindrical pores. The relative permittivity as a function of porosity was compared with effective media models. Permittivity could be fitted to the Bruggeman 1/3 power law over a porosity range from 5% to 78%. 相似文献
474.
We present a study of the drift, in terms of cantilever deflections without probe/target interactions, of polymeric SU8 cantilevers. The drift is measured in PBS buffer (pH 7.4) and under vacuum (1 mbar) conditions. We see that the cantilevers display a large drift in both environments. We believe this is because the polymer matrix absorbs liquid in one situation whereas it is being degassed in the other. An inhomogeneous expansion/contraction of the cantilever is seen because one surface of the cantilever may still have remains of the release layer from the fabrication. To further study the effect, we coat the cantilevers with a hydrophobic coating, perfluorodecyltrichlorosilane (FDTS). Fully encapsulating the SU8 cantilever greatly reduces the drift in liquid whereas a less significant change is seen in vacuum. 相似文献
475.
Zachary J. Taylor Gregory A. Kopp 《Journal of Wind Engineering & Industrial Aerodynamics》2010,98(12):864-871
Although the aerodynamic cause of the collapse of the Tacoma Narrows Bridge is known to be flutter, there is still little known about the fluid mechanics of this phenomenon. Wind tunnel testing ensures that other bridges should not fail due to this instability, but flow field measurements, other than point measurements, are rare. Recent hypotheses have attributed the cause of the instability to the timing of vortices moving around the deck; however, there is minimal flow data to support this notion. In the current work, measurements were performed using the section model technique on a rectangular cross-section (chord/thickness=7) at different points during the build-up of flutter. These measurements include displacement measurements and high-speed PIV measurements. Experiments were also performed on a static body. The results confirm that the shedding frequency and frequency of the body motion are indeed distinct and both can be observed throughout the build-up of flutter. Moreover, it is shown that the vortex shedding activity changes minimally from that of a static body to one that is experiencing bluff body flutter. These results indicate that the timing of leading edge vortices cannot be the cause of the flutter instability. 相似文献