全文获取类型
收费全文 | 99篇 |
免费 | 2篇 |
专业分类
电工技术 | 2篇 |
综合类 | 1篇 |
化学工业 | 8篇 |
机械仪表 | 16篇 |
建筑科学 | 7篇 |
能源动力 | 1篇 |
轻工业 | 16篇 |
武器工业 | 2篇 |
无线电 | 4篇 |
一般工业技术 | 33篇 |
冶金工业 | 1篇 |
自动化技术 | 10篇 |
出版年
2019年 | 2篇 |
2013年 | 1篇 |
2012年 | 9篇 |
2011年 | 8篇 |
2010年 | 2篇 |
2008年 | 10篇 |
2007年 | 4篇 |
2006年 | 8篇 |
2005年 | 11篇 |
2004年 | 7篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 4篇 |
1999年 | 7篇 |
1998年 | 8篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
排序方式: 共有101条查询结果,搜索用时 15 毫秒
1.
并行工程的实施,对提高企业的竞争力起到重要的作用。本文介绍了并行工程的概念,特点,实施环境,应用实例,重点讨论了实施并行工程的关键技术。 相似文献
2.
集成化钣金CAPP系统的研制 总被引:1,自引:0,他引:1
本文介绍一个适用于钣金加工的CAPP系统,该系统采用特征图形法描述零件的几何信息,并应用创成式原理,自动生成钣金件的工艺规程,同时以计算机图形显示方式模拟整个加工过程。 相似文献
3.
Nanoplasmonic sensing is typically based on quantification of changes in optical extinction or scattering spectra. Here we explore the possibility of facile self-referenced hydrogen sensing based on angle-resolved spectroscopy. We found that heterodimers built from closely spaced gold and palladium nanodisks exhibit pronounced directional scattering, that is, for particular wavelengths, much more light is scattered toward the Au than toward the Pd particle in a dimer. The effect is due to optical phase shifts associated with the material asymmetry and therefore highly sensitive to changes in the permittivity of Pd induced by hydrogen loading. In a wider perspective, the results suggest that directional scattering from bimetallic antennas, and material asymmetry in general, may offer many new routes toward novel nanophotonic sensing schemes. 相似文献
4.
Creating hot nanoparticle pairs for surface-enhanced Raman spectroscopy through optical manipulation
We use optical tweezers to move single silver nanoparticles into near-field contact with immobilized particles, forming isolated surface-enhanced Raman spectroscopy (SERS) active Ag particle dimers. The surface-averaged SERS intensity increases by a factor approximately 20 upon dimerization. Electrodynamics calculations indicate that the final approach between the particles is due to "optical binding". The described methodology may facilitate controlled single molecule SERS analysis. 相似文献
5.
Standardized tests fail to assess the effects of antibiotics on environmental bacteria 总被引:2,自引:0,他引:2
Pharmaceuticals are designed and used because of their specific biological effects. Over the past decade, compounds from various classes of pharmaceuticals have been detected in the environment. Concern has grown about the adverse effects pharmaceuticals in the environment might potentially have on human and ecological health. A sound risk assessment is therefore urgently needed for pharmaceuticals. Standardized tests for assessing the effects of chemicals on environmental organisms are widely used for this purpose. However it is questionable whether classical standardized tests give reliable data needed for environmental risk assessment. In this study we investigated the suitability of the respiration inhibition test OECD 209 for the assessment of the effects of antibiotics, disinfectants and cytotoxics on sewage sludge bacteria. We found that inhibition concentrations can strongly depend on the test period and the type of compound. We conclude that tests to assess the effects of pharmaceuticals on environmental organisms such as bacteria have to be evaluated before their results can be used in environmental risk assessment. 相似文献
6.
Traversing step obstacles with manual wheelchairs 总被引:1,自引:0,他引:1
Petzäll J 《Applied ergonomics》1996,27(5):327-341
In the public transport system, there are sometimes step obstacles, such as curbs, steps, entrance steps of vehicles, edges of lifting platforms, internal steps in vehicles, etc. This paper describes research work carried out in Sweden to specify the heights of step obstacles possible to traverse with a manual wheelchair manoeuvred by an attendant. The work included trials with the subjects manoeuvring two different kinds of wheelchairs, with dummies as occupants, over a step obstacle with adjustable height. It also included trials with a person in the wheelchair. The subjects were 20 healthy persons in the age range of 23-60 years, with no or only little experience of manoeuvring wheelchairs, chosen to represent bus drivers or other helpers. They rated their perceived feeling of effort on a 10-level rating scale with ratio properties. The occupant rated the feeling of comfort and safety in three grades. All trials were recorded using a video-camera. From the video-film, the situations and series of actions of the subjects were analysed and the length of time for each task was measured. The forces needed when traversing step obstacles with a wheelchair were calculated according to the principles of mechanics and processed by a computer for the different principal traversing situations. The results show that for the planning of systems for public transportation, where the passenger can get assistance, a step height of 50 mm is acceptable, and a step height of 100 mm can be acceptable if there is enough room to manoeuvre the wheelchair, so that it is possible to choose the most convenient way to traverse the step. Higher heights should be avoided. 相似文献
7.
Knoll P Gröller E Höll K Mirzaei S Koriska K Köhn H 《IEEE transactions on medical imaging》2000,19(12):1258-1261
Distributed computing that uses dynamic networks will change the way we work and communicate thanks to the interaction of devices and services, that are automatically added and removed from the network as needed. The Jini technology, which is built atop the Java programming language, provides a homogenous view of the network and extends the ability of code to migrate in Java. This software design model simplifies the configuration and access to hardware devices and software services in a network. Thus, it becomes possible to execute new services without pre-installing software on client machines. This new programming paradigm is especially important in medical applications, where the reliable transmission of information is essential. This paper demonstrates how single photon emission computerized tomography data can be iteratively reconstructed using a Jini service. 相似文献
8.
Dmitriev A Hägglund C Chen S Fredriksson H Pakizeh T Käll M Sutherland DS 《Nano letters》2008,8(11):3893-3898
We present a straightforward method to double the refractive index sensitivity of surface-supported nanoplasmonic optical sensors by lifting the metal nanoparticles above the substrate by a dielectric nanopillar. The role of the pillar is to substantially decrease the spatial overlap between the substrate and the enhanced fields generated at plasmon resonance. Data presented for nanodisks and nanoellipsoids supported by pillars of varying heights are found to be in excellent agreement with electrodynamics simulations. The described concepts apply to multitude of plasmonic nanostructures, fabricated by top-down or bottom-up techniques, and are likely to further facilitate the development of novel nanooptical sensors for biomedicine and diagnostics. 相似文献
9.
10.