全文获取类型
收费全文 | 68篇 |
免费 | 3篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 13篇 |
金属工艺 | 1篇 |
能源动力 | 13篇 |
轻工业 | 1篇 |
无线电 | 4篇 |
一般工业技术 | 22篇 |
冶金工业 | 10篇 |
自动化技术 | 5篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 1篇 |
2015年 | 6篇 |
2014年 | 5篇 |
2013年 | 4篇 |
2012年 | 5篇 |
2011年 | 7篇 |
2010年 | 6篇 |
2009年 | 2篇 |
2008年 | 3篇 |
2007年 | 1篇 |
2005年 | 1篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1983年 | 1篇 |
1976年 | 4篇 |
排序方式: 共有71条查询结果,搜索用时 703 毫秒
1.
The polycrystalline samples of Dy
x
Bi1−x
FeO3 (x = 1, 0.8, 0.6, 0.4 and 0.2) were synthesized by standard solid state reaction technique. The samples synthesized were characterized
by X-ray diffraction (XRD) technique. Further the samples were characterized by infrared (IR) spectroscopic technique. The
dielectric measurements were carried out as a function of frequency in the range 100 Hz to 1 MHz at room temperature. Also
the dielectric measurements were carried out as a function of temperature at certain fixed frequencies. The ac and dc resistivity
measurements were carried out using two probe method. Also temperature dependence of ac and dc resistivity was noted. These
measurements suggest polaron conduction in the samples. Finally, the data from XRD, IR, dielectric measurements were correlated. 相似文献
2.
Activated sludge wastewater treatment processes are difficult to be controlled because of their complex and nonlinear behavior, however, the control of the dissolved oxygen level in the reactors plays an important role in the operation of the facility. For this reason a new approach is studied in this paper using simulated case-study approach: model predictive control (MPC) has been applied to control the dissolved oxygen concentration in an aerobic reactor of a wastewater treatment plant. The control strategy is investigated and evaluated on two examples using systematic evaluation criteria: in a simulation benchmark – developed for the evaluation of different control strategies – the oxygen concentration has to be maintained at a given level in an aerobic basin; and a changing oxygen concentration in an alternating activated sludge process is controlled using MPC technique. The effect of some MPC tuning parameters (prediction horizon, input weight, sampling time) are also investigated. The results show that MPC can be effectively used for dissolved oxygen control in wastewater treatment plants. 相似文献
3.
C. S. Pawar M. P. Gujar V. L. Mathe 《Journal of Superconductivity and Novel Magnetism》2017,30(3):615-625
Nano crystalline Zn-substituted Ni ferrite films with compositions of Ni1?xZnxFe2O4 (x = 0.25, 0.50, 0.75) were synthesized by sol–gel spin coating method. The synthesized films were characterized for their structural, morphology, optical, electric, and magnetic properties using x-ray diffraction, scanning electron microscope, UV-Vis spectrometer, two probe resistivity, and vibrating sample magnetometer techniques, respectively. The corresponding results indicate that zinc content has significant effect on physical, magnetic, and optical properties of the ferrite. X-ray diffraction studies of thin films showed that the samples have pure cubic spinel phase. The crystallite size is of the nanoparticles estimated using Debey-Scherrer’s method was found to be in the range of 10.27 to 14.97 nm. The lattice parameter was found to be increased from 8.35 to 8.40 Å with increasing Zn2+ contents. The morphology of the thin films depicted the formation of well-developed nano-sized clusters with homogeneous and agglomerated. The optical absorption seen to be affected due to the presence of Zn in Ni-Zn ferrite thin films. Ni-Zn ferrite thin films possess small coercivity and remnant magnetization, which indicates the soft magnetic nature of the material. Electrical resistivity of the films decreases with increasing temperature, suggesting the semiconducting nature of the samples. 相似文献
4.
We consider the estimation of affine transformations aligning a known 2D shape and its distorted observation. The classical way to solve this registration problem is to find correspondences between the shapes and then compute the transformation parameters from these landmarks. Here we propose a novel approach where the exact transformation is obtained as the solution of a polynomial system of equations. The method has been tested on synthetic as well as on real images and its robustness in the presence of segmentation errors and additive geometric noise has also been demonstrated. We have successfully applied the method for the registration of hip prosthesis X-ray images. The advantage of the proposed solution is that it is fast, easy to implement, has linear time complexity, works without established correspondences and provides an exact solution regardless of the magnitude of transformation. 相似文献
5.
Tendamudzimu Ramulifho Kenneth I. Ozoemena Remegia M. Modibedi Charl J. Jafta Mkhulu K. Mathe 《Electrochimica acta》2012
The preparation of metal nanoparticles (Pd, Ni, Sn) supported on sulfonated multi-walled carbon nanotubes (SF-MWCNTs) using a very rapid microwave-assisted solvothermal strategy has been described. Electrocatalytic behaviour of the SF-MWCNT-Pd and its ‘mixed’ bimetallic electrocatalysts (i.e., SF-MWCNT-PdSnmix and SF-MWCNT-PdNimix) towards ethanol oxidation in alkaline medium was investigated. The result shows that the mixed Pd-based catalysts (obtained by simple ultrasonic-mixing of the individual MWCNT-metal nanocomposites) gave better electrocatalytic activity than their alloy nanoparticles (obtained by co-reduction of metal salts) or Pd alone. The SF-MWCNT platform gave better electrocatalytic performance compared to the unsulfonated and commercial Vulcan carbons. Detailed electrochemical studies (involving cyclic voltammetry, chronoamperometry, chronopotentiometry, and impedance spectroscopy) prove that the electrocatalytic oxidation of ethanol at the SF-MWCNT-PdNimix platform is more stable, occurs at lower potential, gives lower Tafel slopes, with faster charge-transfer kinetics compared to its SF-MWCNT-PdSnmix counterpart. Also, result revealed that SF-MWCNT-PdNimix is more tolerant to CO poisoning than the SF-MWCNT-PdSnmix. The results provide some important insights into the electrochemical response of microwave-synthesised Pd-based bimetallic catalysts for potential application in direct ethanol alkaline fuel cell technology. 相似文献
6.
7.
Jianwei Ren Nicholas M. Musyoka Henrietta W. Langmi Brian C. North Mkhulu Mathe Xiangdong Kang 《International Journal of Hydrogen Energy》2014
The fabrication of core–shell nanocrystals by incorporating microporous UiO-66 into mesoporous MIL-101 is reported. The growth of the core–shell MIL-101@UiO-66 nanocrystals was observed and supported by TEM and PXRD. The accessible pore volumes of the individual metal-organic framework (MOF) components and the core–shell hybrid crystals were also characterized. The hydrogen storage capacity exhibited by the resulting core–shell nanocrystals was 26% and 60% higher than those of pure phase MIL-101 and UiO-66, respectively. Finally, the fabricated core–shell MIL-101@UiO-66 structure exhibited a high degree of moisture tolerance. 相似文献
8.
太赫兹波段电磁超介质的应用及研究进展 总被引:1,自引:0,他引:1
太赫兹波和电磁超介质是电磁学领域关注的热点.太赫兹波与电磁超介质相互作用可以实现对太赫兹波的操纵和调控,有望填补"太赫兹空白".介绍了太赫兹波段电磁超介质的研究进展,包括电磁超介质电磁性能可调谐的实施途径,电磁超介质在太赫兹功能器件方面的应用(调制器/开关、传感器/探测器、滤波器、偏振元件和吸波器),太赫兹波段表面等离... 相似文献
9.
Abstract It is shown that the deflection of an atom de Broglie wave at two adjacent cavities containing non-resonant weak fields can yield a highly entangled quantum state of the atom–field system in which discernible atomic beams are entangled to internal states of the atom and to two-mode photon-number states of the fields. Two-mode anticorrelated entangled photon-number states characterized by the total photon number can be prepared by the detection of the atom in given directions of the propagation. 相似文献
10.