首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   50篇
  免费   2篇
化学工业   12篇
金属工艺   1篇
机械仪表   2篇
能源动力   1篇
轻工业   2篇
石油天然气   2篇
无线电   7篇
一般工业技术   10篇
冶金工业   7篇
自动化技术   8篇
  2023年   1篇
  2021年   4篇
  2020年   4篇
  2019年   4篇
  2018年   3篇
  2017年   2篇
  2016年   2篇
  2015年   1篇
  2014年   2篇
  2013年   1篇
  2011年   3篇
  2008年   2篇
  2006年   3篇
  2002年   1篇
  1998年   4篇
  1997年   3篇
  1996年   1篇
  1992年   2篇
  1990年   3篇
  1988年   1篇
  1985年   1篇
  1984年   2篇
  1983年   1篇
  1982年   1篇
排序方式: 共有52条查询结果,搜索用时 0 毫秒
1.
Indium tin oxide‐coated thin films (200 nm) are deposited on glass substrates by using R.f. sputtering technique. Here, we investigate the influence of new technique of treatment, which is called as “oil thermal annealing” on the nano‐structured indium tin oxide thin films at fixed temperature (150 °C) which improves adhesion strength, electrical conductivity and optical properties (transmittance) of the films. Oil thermal annealing is used to reduce inherent defects that may be introduced during the prepared thin film and cooling processes. Proposed technique is highly suitable for liquid crystal displays, solar cells and organic light emitting diodes, and many other display‐related applications.  相似文献   
2.
3.
We derive an expression for the rate of spin diffusion between 13C nuclei based on a simple model appropriate for organic solids. In this model, couplings between carbons and protons and among protons are included only as a source of fluctuating local magnetic fields at the carbon nuclei. Our results are essentially equivalent to the results of previous calculations in which the surrounding protons are treated quantum mechanically using memory function formalisms.  相似文献   
4.
Amyloid is a biophysically defined, biochemically non-uniform protein which is deposited in the tissue, forming a cross-beta configuration. In paraffin sections it is demonstrated using Congo red staining according to Puchtler et al. and a polarizing microscope with a tension-free clean optic system that shows a typical apple-green birefringence. The identification of amyloid has to be followed by immunostaining for AA, ATTR, A lambda, A kappa and A beta 2 microglobulin and possibly further types of amyloids for classification purposes. Considering the localization, expansion and type localized and generalized types probably can be differentiated. The latter should be correlated to a basic disease. The treatment of the basic disease is the only chance for reducing or eliminating the amyloid deposits. In this review, the modern morphological methods for demonstration and both immunohistological and clinical classification of amyloid and amyloidoses are presented. Rare types are mentioned in the tables.  相似文献   
5.
6.
Studies of air pollution by metals contained in dust particules usually require mineralization of a dust-collecting filter. This treatment introduces impurities into the sample. To avoid such contamination, an anodic stripping cell was constructed requiring no preliminary treatment of the sample filter. The cell uses a three-electrode amperometric system in differential pulse anodic stripping mode (DPAS). Solubilization of the metals from dust by a complexing agent, instead of the strong acid normally encountered in other methods, allows selective determination of metals according to their chemical form. With this cell, minimal handling of the collection filter and a large area mercury-coated vitreous carbon electrode located close to the sample filter (2 mm) lead to limits of detection as low as 0.15 μg of lead and 10 ng of copper. Precision is 2% for lead determination and 4% for copper determination (RSD).  相似文献   
7.
In this paper, we consider the downlink of a multiuser wireless communication system with multiple antennas at the base station and users each with a single receive antenna. It is known that when channel state information (CSI) is available at the transmitter a large performance gain can be achieved. In a system employing time-division duplexing (TDD), CSI can be obtained at the base station if there is reciprocity between the forward and reverse channels. CSI can also be conveyed from the users to the base station via a limited-rate feedback channel in a frequency-division duplexing (FDD) system. In any case, channel estimation errors are inevitable due to the presence of background noise in the estimated signal and due to the finite number of feedback bits used in a limited-rate feedback system model. In this paper, we first consider the general case when partial CSI is available at the transmitter. We derive an MMSE based precoding technique that considers channel estimation errors as an integral part of the system design. Using rate-distortion theory and the generalized Lloyd vector quantization algorithm, we then specialize our results for the more practical limited-rate feedback system model. Compared to previously proposed precoding techniques such as channel inversion and regularized channel inversion, it is shown that the proposed precoding technique significantly improves the average bit error rate (BER) in the system. Furthermore, the performance of the proposed technique is investigated in the high signal-tonoise ratio (SNR) regime, and similar to [1], [2], it is shown that the proposed technique suffers from a ceiling effect that asymptotically limits the system performance.  相似文献   
8.
Microsystem Technologies - This article deals with the wave propagation problem of nanosize double-layered plates while subjected to a longitudinal magnetic field. To achieve more reliable answers,...  相似文献   
9.
Wireless Networks - Radio over free space optics (Ro-FSO) systems have previously relied on the signal intensity, wavelength and polarization for multiplexing data streams in...  相似文献   
10.
We propose a multiscale approach to study the influence of carbon nanotubes’ agglomeration on the stability of hybrid nanocomposite plates. The hybrid nanocomposite consists of both macro- and nano-scale reinforcing fibers dispersed in a polymer matrix. The equivalent material properties are calculated by coupling the Eshelby-Mori-Tanaka model with the rule of mixture accounting for effects of CNTs inside the generated clusters. Furthermore, an energy based approach is implemented to obtain the governing equations of the problem utilizing a refined higher-order plate theorem. Subsequently, the derived equations are solved by Galerkin’s analytical method to predict the critical buckling load. The influence of various boundary conditions is studied as well. After validation, a set of numerical examples are presented to explain how each variant can affect the plate’s natural frequency.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号