全文获取类型
收费全文 | 132篇 |
免费 | 7篇 |
国内免费 | 1篇 |
专业分类
综合类 | 22篇 |
化学工业 | 4篇 |
金属工艺 | 4篇 |
机械仪表 | 18篇 |
建筑科学 | 27篇 |
矿业工程 | 2篇 |
轻工业 | 16篇 |
水利工程 | 3篇 |
石油天然气 | 25篇 |
武器工业 | 1篇 |
无线电 | 4篇 |
一般工业技术 | 3篇 |
冶金工业 | 1篇 |
原子能技术 | 2篇 |
自动化技术 | 8篇 |
出版年
2023年 | 3篇 |
2022年 | 2篇 |
2021年 | 7篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 4篇 |
2015年 | 5篇 |
2014年 | 4篇 |
2013年 | 5篇 |
2012年 | 10篇 |
2011年 | 3篇 |
2010年 | 8篇 |
2009年 | 12篇 |
2008年 | 17篇 |
2007年 | 6篇 |
2006年 | 6篇 |
2005年 | 6篇 |
2004年 | 10篇 |
2003年 | 7篇 |
2002年 | 4篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
排序方式: 共有140条查询结果,搜索用时 15 毫秒
41.
42.
The electrohydrodynamic instability of the interface between two viscous fluids with different electrical properties in plane Poiseuille flow has recently found applications in mixing and droplet formation in microfluidic devices. In this paper, we perform the stability analysis in the case where the fluids are assumed to be leaky dielectrics. The two-layer system is subjected to an electric field normal to the interface between the two fluids. We make no assumption on the magnitude of the ratio of fluid to electric time scales, and thus solve the full conservation equation for the interfacial charge. The electric field is found to be either stabilizing or destabilizing, and the influence of the various parameters of the problem on the interface stability is thoroughly analyzed. 相似文献
43.
Mitsuishi K Iakoubovskii K Takeguchi M Shimojo M Hashimoto A Furuya K 《Ultramicroscopy》2008,108(9):981-988
An efficient, Bloch wave-based method is presented for simulation of high-resolution scanning confocal electron microscopy (SCEM) images. The latter are predicted to have coherent nature, i.e. to exhibit atomic contrast reversals depending on the lens defocus settings and sample thickness. The optimal defocus settings are suggested and the 3D imaging capabilities of SCEM are analyzed in detail. In particular, by monitoring average image intensity as a function of the probe focus depth, it should be possible to accurately measure the depth of a heavy-atom layer embedded in a light-element matrix. 相似文献
44.
D'Alfonso AJ Cosgriff EC Findlay SD Behan G Kirkland AI Nellist PD Allen LJ 《Ultramicroscopy》2008,108(12):1567-1578
The implementation of spherical aberration-corrected pre- and post-specimen lenses in the same instrument has facilitated the creation of sub-Angstrom electron probes and has made aberration-corrected scanning confocal electron microscopy (SCEM) possible. Further to the discussion of elastic SCEM imaging in our previous paper, we show that by performing a 3D raster scan through a crystalline sample using inelastic SCEM imaging it will be possible to determine the location of isolated impurity atoms embedded within a bulk matrix. In particular, the use of electron energy loss spectroscopy based on inner-shell ionization to uniquely identify these atoms is explored. Comparisons with scanning transmission electron microscopy (STEM) are made showing that SCEM will improve both the lateral and depth resolution relative to STEM. In particular, the expected poor resolution of STEM depth sectioning for extended objects is overcome in the SCEM geometry. 相似文献
45.
Inelastic image simulation software is presented, implementing the double channeling approximation which takes into account the combination of multiple elastic and single inelastic scattering in a crystal. The approach is described with a density matrix formalism. Two applications in high resolution energy filtered (EFTEM) transmission electron microscopy (TEM) images are presented: thickness-defocus maps for SrTiO3 and exit plane intensities for an (LaAlO3)3(SrTiO3)3 multilayer system. Both systems show a severe breakdown in direct interpretability which becomes worse for higher acceleration voltages, thicker samples and lower excitation edge energies. Since this effect already occurs in the exit plane intensity, it is a fundamental limit and image simulations in EFTEM are indispensable just as they are indispensable for elastic high resolution TEM images. 相似文献
46.
归纳总结了长江马鞍山河段基本情况、近期河道演变特点和河道治理概况;根据现有河势条件及近年崩岸险情,分析指出了目前本河段存在的主要问题;结合河道治理规划情况,探讨了下一步河道治理措施。研究认为:河势调整工程是该河段整治的关键,重点是通过数学模型和河工模型试验研究提出河势调整工程方案;主要是在左岸新河口一带布置导流工程和上下何家洲及心滩串沟封堵并岸工程,并辅以江心洲尾的何家洲尾挖槽工程。鉴于整治工程的紧迫性和时效性,建议相关部门尽快开展相关前期工作,为整治工程早日实施创造条件,进而实现该河段河势的稳定。 相似文献
47.
针对准噶尔盆地西北缘玛2井区致密储层裂缝的发育情况及空间分布和尺寸难以定量预测的难题,在利用岩心、薄片、成像测井等资料对裂缝特征进行分析的基础上,利用Petrel的Kinetix裂缝模拟模块,基于地应力场的数值模拟技术,定量预测裂缝尺寸及空间分布,并对模拟结果进行验证。研究结果表明:玛2井区裂缝以剪切裂缝为主,裂缝密度为5~6条/m,并逐渐向两翼延伸,裂缝开度为0.00~0.20 mm;玛2井区裂缝分布具有明显的纵向非均质性和平面非均质性特征,裂缝集中发育段和裂缝不发育段相间出现,大部分断裂带附近裂缝发育程度高。利用水平井微地震监测资料与裂缝模型模拟结果相互证实裂缝分布的长度、宽度等空间展布特征更合理。该研究成果可为玛湖油田玛2井区开发方案的实施与优化提供重要依据。 相似文献
48.
长庆气田可动地层水特征及意义 总被引:6,自引:0,他引:6
长庆气田的出水层主要分布于马五1段,根据测井检测数据,可分为产水不产气、气水同产及产气不(少)产水型.表面上看,长庆气田马五1储层的地层水呈块状或透镜状分布,无连片水体.实际上,该区地层水并非完全独立,气藏中不存在"边水"或"底水",找不到绝对的气水边界,只存在一些相对富集的区域,即相对富水区.通过利用地震、测井资料对地层水横向追踪,发现该区存在约20个相对富水区.大面积气区中气井出水,并不影响气的产出,在相对富水区边缘,由于出水采气导致水体与井底压差增大,可能造成气井很快出水且水量急增,但可通过控制生产压差(<3 MPa)或采用排水恢复产气. 相似文献
49.
Karen A Franck 《Architectural Design》2005,75(1):117-124
Amid the chaotic frenzy of Hong Kong emerges an architectural voice of calm Karen A Franck encounters the work of Denise Ho, an architect who distinguishes herself through her quest for harmony and her careful consideration of her clients' needs. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
50.
Edward Denison and Guang Yu Ren, authors of Building Shanghai (Wiley-Academy 2006), a narrative history of Shanghai's architectural development, review two new books on China that focus solely on its 21st-century resurgence. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献