全文获取类型
收费全文 | 98篇 |
免费 | 3篇 |
专业分类
电工技术 | 11篇 |
综合类 | 1篇 |
化学工业 | 22篇 |
机械仪表 | 2篇 |
建筑科学 | 17篇 |
能源动力 | 12篇 |
轻工业 | 3篇 |
无线电 | 1篇 |
一般工业技术 | 17篇 |
冶金工业 | 1篇 |
原子能技术 | 1篇 |
自动化技术 | 13篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2014年 | 4篇 |
2013年 | 5篇 |
2012年 | 3篇 |
2011年 | 4篇 |
2010年 | 9篇 |
2009年 | 5篇 |
2008年 | 6篇 |
2007年 | 2篇 |
2005年 | 4篇 |
2004年 | 4篇 |
2003年 | 3篇 |
2002年 | 4篇 |
2001年 | 1篇 |
1999年 | 2篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 5篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1987年 | 1篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有101条查询结果,搜索用时 0 毫秒
1.
Far-infrared reflection spectra of dielectric ceramics, BaSm2 Ti5 O14 , BaTi4 O9 , and some pcrovskites such as Ba(Zn1/3 Nb2/3 )O3 , have been measured at room temperature using a Fourier transform infrared spectrometer in order to investigate the effect of the crystal structure on the dielectric properties. As for perovskites, Sr(Zn1/3 Nb2/3 )O3 and Sr(Mg1/3 Nb2/3 )O3 , in which B site ions are ordered, were also measured. Reflectance data were analyzed by means of a factorized form of dielectric functions instead of the classical dispersion theory, and all of the spectra were well fitted. The values of dielectric constants and tan δ calculated from the reflectance data were in good agreement with resonant cavity measurements at 5 GHz. Furthermore, results of this study have shown that the main contribution to the microwave dielectric properties is caused by low-frequency optically active modes located at 50 to about 300 cm−1 , and for perovskite structures it is suggested that the ordering of B site ions is significant in obtaining low dielectric losses. 相似文献
2.
Orderly stimulation of skeletal muscle motor units with tripolarnerve cuff electrode 总被引:4,自引:0,他引:4
Baratta R. Ichie M. Hwang S.K. Solomonow M. 《IEEE transactions on bio-medical engineering》1989,36(8):836-843
An electrical nerve stimulation technique, using single tripolar electrode, was shown to be capable of recruiting motor units according to their size, while allowing simultaneous but independent control of firing rate in the active units. Test paradigms consisting of established fundamental physiological concepts of soleus-gastrocnemius architecture, motor units conduction velocity, firing rate behavior of motor units of different sizes, and their susceptibility to fatigue were employed to validate the technique and demonstrate its utility as a basic and applied research tool. 相似文献
3.
Summary CP/DD/MASS 13C-NMR spectra have been obtained for regenerated cellulose samples with different crystallinities as well as for cotton, -D-glucose, -D-cellobiose, and cellopentaose. The spectra of the regenerated cellulose samples exhibit broad multiplicities of the C-4 and C-6 resonance lines in a similar manner as those of native cellulose samples such as cotton and ramie, and, in addition, another broad tailing of the C-1 resonance. Since these multiplicities change linearly with crystallinity, it is concluded that they are ascribed to the contributions from the crystalline and noncrystalline components. Effects of hydrogen bonds and conformations of the -1,4-glycosidic linkage on the chemical shifts are also discussed. 相似文献
4.
This paper proposes a systematic technique to design multiple robust H∞ controllers. The proposed technique achieves a desired robust performance objective, which is impossible to achieve with a single robust controller, by dividing the uncertainty set into several subsets and by designing a robust controller to each subset. To achieve this goal with a small number of divisions of the uncertainty set, an optimization problem is formulated. Since the cost function of this optimization problem is not a smooth function, a numerical nonsmooth optimization algorithm is proposed to solve this problem. This method avoids the use of Lyapunov variables, and therefore it leads to a moderate size optimization problem. A numerical example shows that the proposed multiple robust control method can improve the closed‐loop performance when a single robust controller cannot achieve satisfactory performance. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
5.
Toshihiko Hirama Masashi Goto Keiji Shiba Toshio Kobayashi Ryozo Tanaka Shizuo Tsurumaki Katsuki Takiguchi Hiroshi Akiyama 《Nuclear Engineering and Design》2005,235(13):7
A 1/8-scale model was constructed of a reinforced concrete containment vessel (RCCV) used in the latest advanced boiling water reactors (ABWR). Shaking table tests were conducted on it with input motions corresponding to or exceeding a design earthquake assumed for a real Nuclear Power Plant.The objectives of the tests were to verify the structural integrity and the leak-proof functional soundness of the RCCV subjected to design earthquakes, and to determine the ultimate strength and seismic margin by an excitation that led to the model's collapse. The model, the test sequence and the pressure and leak test results were addressed in Part 1. The shaking table test method, the input motions and the test results, including the transition of the model's stiffness, natural frequencies and damping factors and the effects of vertical input motions and internal pressure on the model's characteristics and behavior, the load–deformation, the ultimate strength, the failure mode of the reinforced concrete portion and the liner plate are described here. The seismic safety margin that was evaluated by the energy input during the failure test to a design basis earthquake will be described in Part 3. The analytical results of simulation using the multi-lumped mass model will be described in Part 4. 相似文献
6.
The choice of the best mesh in terms of cost, time and accuracy of computational solutions in the CFD industry is a challenging topic and a subject of some controversy. Generating meshes based on hexahedral elements requires significant time and effort, however, these meshes are claimed to produce high quality solutions. Meshes that employ tetrahedral elements can be constructed much faster in complex geometries, but may increase the levels of numerical diffusion. The objective of this study is to better establish quantitative assessment of the influence of cell geometry in the computational mesh on the CFD results of pollutant dispersion around buildings in order to help modelers to choose the most effective mesh type for their applications. In order to achieve this objective, two widely used mesh styles, i.e., hexahedral-based and tetrahedral-based meshes, are considered in the simulation of this flow problem. Quantitative grid convergence was calculated based on a grid convergence index (GCI). The mesh style was found to have an observable effect on the calculated pollutant concentrations. For instance, the hexahedral-based mesh was observed to have GCI values that were in an order of magnitude below the tetrahedral-based mesh values for all resolutions considered, even in the very fine tetrahedral-based mesh. Furthermore, the GCI value, and hence the truncation error, remains high compared to conventional hexahedral cases. The study recommends taking special care when employing an unstructured tetrahedral-based mesh to ensure that the mesh is fine enough and any numerical errors should be documented for selected variables reported analogous to experimental uncertainty in order to assess the quality of the numerical solution. 相似文献
7.
Shuichi Kawamata Kiichi Okuda Takahiko Sasaki Ryozo Yoshizaki 《Journal of Low Temperature Physics》1999,117(3-4):891-895
The magnetic field direction dependence of the magnetic torque in the superconducting state of Bi
2
Sr
1.65
La
0.35
CuO
6+
(Bi2201) single crystal has been measured in several static magnetic fields up to 200 kOe. The applied field dependence of the anisotropy parameter, , defined by the square root of the effective mass ratio has been obtained by fitting the magnetic torque curves at 17 K by means of the effective mass model. For Bi
2
Sr
2
CaCu
2
O
8+
(Bi2212), the values up to 210 kOe were reported previously. At each field, for Bi2201 is larger than that for Bi2212. Since the value decreases as the field increases both for Bi2201 and Bi2212, the reduction of by the application of the high magnetic field is considered to be common for Bi-based layered superconductors. 相似文献
8.
Fumitaka Horii Ryozo Kitamaru Shiro Maeda A. Saika Takehiko Terao 《Polymer Bulletin》1985,13(2):179-184
Summary High-resolution solid-state 13C NMR spectra and 13C relaxation times T1 and T1 have been measured at 40–100° C for uniaxially oriented polyethylene films with the drawing direction parallel to the magnetic field; this sample has a unique morphological structure that the noncrystalline chains are nearly disordered irrespective of the high degree of drawing. A sharp resonance line(line A) appears at the position corresponding to the principal value 33 of the chemical shift tensor for the CH2 carbons with the trans-trans conformation. Another sharp linedine B) is observed at almost the same chemical shift as for the CH2 carbons of polyethylene in solution. Although these observations are similar to those for a cold-drawn polyethylene sample reported previously, line B is much enhanced in intensity and the linewidth is narrower in the present sample, reflecting the disorientation of the noncrystalline component. It is found from T1 measurements that line A contains two components with different molecular mobility, both being assigned to the crystalline components. On the other hand, the line B is composed of a single component assignable to the noncrystalline component with liquid-like molecular mobility. 相似文献
9.
Teruhiko Akazawa Hiroshi Ikeda Norihiko Ozawa Hideki Kouno Ryozo Yoshizaki 《Journal of Low Temperature Physics》1999,117(5-6):1235-1239
In order to investigate a relationship between the carrier concentration and negative magnetoresistance in the underdoped region, we have performed out-of-plane electrical resistivity measurements for underdoped Bi
2
Sr
1.6
La
0.4
CuO
6+
single crystals. Giant negative magnetoresistance has been observed in the most abundant carrier sample with = 0.12 in our experiment. The negative magnetoresistance reduces with decreasing carrier concentration. 相似文献
10.
Masakatsu Maeda Ryozo Oomoto Toshiya Shibayanagi Masaaki Naka 《Metallurgical and Materials Transactions A》2003,34(8):1647-1656
This article presents an effective way to control the interfacial reaction during solid-state diffusion bonding of silicon
nitride (Si3N4) using titanium foils. The interfacial structure and its growth kinetics were analyzed in detail with scanning electron microscopy
(SEM), electron-probe microanalysis (EPMA), and X-ray diffraction (XRD). The actual phase sequence of the joint interfaces
bonded at temperatures between 1473 and 1673 K is concluded to be Si3N4/Ti5Si3(N)/α-Ti(N)+Ti5Si3(N), which is different from the phase sequence observed at room temperature after bonding. The joints are very weak due to
the formation of a brittle Ti5Si3(N) layer at the interface. To suppress the growth of the Ti5Si3 layer, a nitrogen-solution treatment of titanium foils prior to each bonding experiment is implemented. Although a perfect
prevention of the Ti5Si3(N) layer formation is not achieved with this treatment, it is shown that the growth of the layer is effectively suppressed
enough to improve the joint strength to a level 3 times higher than the case in which pure titanium is employed. 相似文献