全文获取类型
收费全文 | 87篇 |
免费 | 8篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 23篇 |
金属工艺 | 1篇 |
机械仪表 | 14篇 |
能源动力 | 2篇 |
轻工业 | 4篇 |
石油天然气 | 2篇 |
无线电 | 14篇 |
一般工业技术 | 18篇 |
冶金工业 | 3篇 |
自动化技术 | 12篇 |
出版年
2021年 | 2篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2018年 | 4篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 4篇 |
2014年 | 2篇 |
2013年 | 4篇 |
2012年 | 7篇 |
2011年 | 2篇 |
2010年 | 3篇 |
2009年 | 7篇 |
2008年 | 7篇 |
2007年 | 5篇 |
2006年 | 4篇 |
2005年 | 4篇 |
2004年 | 2篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有95条查询结果,搜索用时 375 毫秒
81.
Amorphous Semiconductors: Ionic Liquid Activation of Amorphous Metal‐Oxide Semiconductors for Flexible Transparent Electronic Devices (Adv. Funct. Mater. 17/2016)
下载免费PDF全文
![点击此处可从《Advanced functional materials》网站下载免费的PDF全文](/ch/ext_images/free.gif)
82.
Park YK Bold B Lee WK Jeon MH An KH Jeong SY Shim YK 《International journal of molecular sciences》2011,12(5):2946-2957
d-(+)-Galactose-conjugated single-walled carbon nanotubes (SWCNTs) were synthesized for use as biosensors to detect the cancer marker galectin-3. To investigate the binding of galectin-3 to the d-(+)-galactose-conjugated SWCNTs, an electrochemical biosensor was fabricated by using molybdenum electrodes. The binding affinities of the conjugated SWCNTs to galectin-3 were quantified using electrochemical sensitivity measurements based on the differences in resistance together with typical I-V characterization. The electrochemical sensitivity measurements of the d-(+)-galactose-conjugated SWCNTs differed significantly between the samples with and without galectin-3. This indicates that d-(+)-galactose-conjugated SWCNTs are potentially useful electrochemical biosensors for the detection of cancer marker galectin-3. 相似文献
83.
Seon Hak Kim Oh Jung Kwon Deoksu Hyon Seung Ho Cheon Jin Su Kim Byeong Heon Kim Sung Tack Hwang Jun Seok Song Man Taeck Hwang Byeong Soo Oh 《International Journal of Hydrogen Energy》2013
The fuel cell hybrid system for automobiles consists of a fuel cell/battery or fuel cell/super-capacitor. The motor in the regenerative braking system revives electrical energy instead of dissipating heat during braking. In this study, an additional generator in a fuel cell/battery hybrid system is equipped and tested as an alternative to using a motor for regenerative braking. The fuel cell hybrid system uses the Nexa™ Power Module from Ballard Power Systems Inc. and a Ni-MH battery from Global Battery Co., Ltd. In the hybrid system, the battery's voltage undershoots, while the fuel cell's voltage does not undershoot. In this study, the fuel cell hybrid system is affected by the load share rates due to the SoC of the battery. Therefore, the SoC of the battery needs to be managed. Also, the dynamic performance of the fuel cell is more stable when comprising the hybrid system. In addition, the efficiency of regenerative braking by using the generator is 63.8%. This shows that the efficiency is significantly improved compared with the 24.2% efficiency of regenerative braking using the motor. 相似文献
84.
The skew-derivative problem for harmonic functions in the exterior of an open arc in a plane is considered. This problem models
the electric current in a semiconductor film from an electrode of arbitrary shape in the presence of a magnetic field. A numerical
method for solving the problem is proposed. The method is based on a boundary-integral-equation approach. The proposed numerical
method is tested. The numerical simulation is presented for different values of the parameters and different shapes of the
electrode. Physical effects found in numerical experiments are discussed. 相似文献
85.
A conservative finite-volume numerical method for unstructured grids with the cell-centered method has been developed for
computing flow and heat transfer by combining the attractive features of the existing pressure-based procedures with the advances
made in unstructured grid techniques. This method uses an integral form of governing equations for arbitrary convex polyhedra.
Care is taken in the discretization and solution procedure to avoid formulations that are cell-shape-specific. A collocated
variable arrangement formulation is developed, i.e. all dependent variables such as pressure and velocity are stored at cell
centers. For both convective and diffusive fluxes the forms superior to both accuracy and stability are particularly adopted
and formulated through a systematic study on the existing approximation ones. Gradients required for the evaluation of diffusion
fluxes and for second-order-accurate convective operators are computed by using a linear reconstruction based on the divergence
theorem. Momentum interpolation is used to prevent the pressure checkerboarding and a segregated solution strategy is adopted
to minimize the storage requirements with the pressure-velocity coupling by the SIMPLE algorithm. An algebraic solver using
iterative preconditioned conjugate gradient method is used for the solution of linearized equations. The flow analysis code
(PowerCFD) developed by the present method is evaluated for its application to several 2-D structured-mesh benchmark problems
using a variety of unstructured quadrilateral and triangular meshes. The present flow analysis code by using unstructured
grids with the cell-centered method clearly demonstrate the same accuracy and robustness as that for a typical structured
mesh. 相似文献
86.
87.
A question answering (QA) system can be built using multiple QA modules that can individually serve as a QA system in and of themselves. This paper proposes a learnable, strategy‐driven QA model that aims at enhancing both efficiency and effectiveness. A strategy is learned using a learning‐based classification algorithm that determines the sequence of QA modules to be invoked and decides when to stop invoking additional modules. The learned strategy invokes the most suitable QA module for a given question and attempts to verify the answer by consulting other modules until the level of confidence reaches a threshold. In our experiments, our strategy learning approach obtained improvement over a simple routing approach by 10.5% in effectiveness and 27.2% in efficiency. 相似文献
88.
Four different structure polyimide thin films based on 1,4‐phenylene diamine (PDA) and 4,4′‐oxydianiline (ODA) were synthesized by using two different dianhydrides, pyromellitic dianhydride (PMDA) and 3,3′,4,4′‐biphenyltetracarboxylic dianhydride (BPDA), and their residual stress behavior and mechanical properties were investigated by using a thin film stress analyzer and nanoindentation method. The residual stress behavior and mechanical properties were correlated to the morphological structure in polyimide films. The morphological structure of polyimide thin films was characterized by X‐ray diffraction patterns and refractive indices. The residual stress was in the range of ?5 to 38 MPa and increased in the following order: PMDA‐PDA < BPDA‐PDA < PMDA‐ODA < BPDA‐ODA. The hardness of the polyimide films increased in the following order: PMDA‐ODA < BPDA‐ODA < PMDA‐PDA < BPDA‐PDA. The PDA‐based polyimide films showed relatively lower residual stress and higher hardness than the corresponding ODA‐based polyimide films. The in‐plane orientation and molecularly ordered phase were enhanced with the increasing order as follows: PMDA‐ODA < BPDA‐ODA < BPDA‐PDA ~ PMDA‐PDA. The PDA‐based polyimides, having a rigid structure, showed relatively better‐developed morphological structure than the corresponding ODA‐based polyimides. The residual stress behavior and mechanical properties were correlated to the morphological structure in polyimide films. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
89.
Myung-Chan Jo Arthur R. Tarrer Young W. Jeon Sang Joon Park Hyon Hee Yoon 《Petroleum Science and Technology》1997,15(3):245-271
Addition of Chemical antistripping agents (ASA)to asphalt has inherent disadvantages such as reduction of the effectiveness of ASA in hot asphalt and formation of relatively weak bond with the aggregate surface. To circumvent such problems, a novel approach of aggregate pretreatment with ASA was investigated in this study. The aggregate was pretreated with aqueous emulsions/solutions of different organic surface modifiers. The effectiveness of this aggregate pretreatment procedure was evaluated to ascertain the asphalt-aggregate bond strength using the boiling water test. Boiling water test was selected for its rapidity and simplicity. The 相似文献
90.
Ivan Arellano Mihail Nazarov Clare Chisu Byeon Elisabeth-Jeanne Popovici Hyojung Kim Hyon Chol Kang Do Young Noh 《Materials Chemistry and Physics》2010,119(1-2):48-51
Yttrium tantalate (YTaO4), yttrium niobium-tantalate (YTaNbO4) and yttrium niobate (YNbO4) doubly doped by Eu3+ and Tb3+, were investigated using X-ray diffraction and X-ray excitation luminescence in order to study their structural and luminescent properties. By means of X-ray diffraction, the crystallographic data for YTaO4 and YNbO4 with double activation by Eu3+ and Tb3+ were first calculated. Under X-ray excitation luminescence, the rare earth emission centers contribute to the overall luminescence. Due to their various luminescence chromaticities, the proposed rare earth activated phosphors are promising materials for optoelectronics as well as for X-ray intensifying screens for medical diagnosis providing the broad variation of visible photoluminescence from blue to red. 相似文献