全文获取类型
收费全文 | 1007篇 |
免费 | 28篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 74篇 |
综合类 | 3篇 |
化学工业 | 312篇 |
金属工艺 | 31篇 |
机械仪表 | 21篇 |
建筑科学 | 22篇 |
能源动力 | 53篇 |
轻工业 | 95篇 |
石油天然气 | 1篇 |
无线电 | 48篇 |
一般工业技术 | 179篇 |
冶金工业 | 64篇 |
原子能技术 | 47篇 |
自动化技术 | 88篇 |
出版年
2023年 | 10篇 |
2022年 | 15篇 |
2021年 | 31篇 |
2020年 | 19篇 |
2019年 | 15篇 |
2018年 | 19篇 |
2017年 | 18篇 |
2016年 | 34篇 |
2015年 | 21篇 |
2014年 | 37篇 |
2013年 | 73篇 |
2012年 | 52篇 |
2011年 | 71篇 |
2010年 | 46篇 |
2009年 | 44篇 |
2008年 | 53篇 |
2007年 | 50篇 |
2006年 | 50篇 |
2005年 | 33篇 |
2004年 | 36篇 |
2003年 | 30篇 |
2002年 | 18篇 |
2001年 | 18篇 |
2000年 | 19篇 |
1999年 | 19篇 |
1998年 | 24篇 |
1997年 | 21篇 |
1996年 | 15篇 |
1995年 | 16篇 |
1994年 | 14篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1991年 | 9篇 |
1990年 | 9篇 |
1989年 | 7篇 |
1988年 | 6篇 |
1987年 | 9篇 |
1986年 | 8篇 |
1985年 | 5篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 7篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 5篇 |
1966年 | 1篇 |
1964年 | 2篇 |
排序方式: 共有1038条查询结果,搜索用时 15 毫秒
991.
Adrian F. L. Hyde Toru Higuchi Kazuya Yasuhara 《Canadian Metallurgical Quarterly》2007,133(4):416-423
Low plasticity silts are liquefiable and the dissipation of pore pressures after an earthquake will be accompanied by densification and compression of the soil skeleton. Anisotropic rather than isotropic stress distributions are commonly found to exist in slopes or silty fills placed under K0 conditions and this can be enhanced further by the weight of overlying structures. Compression after an earthquake generally increases soil resistance but it can still be liquefied by aftershocks. The postcyclic recompression of silt, and postdrainage monotonic and cyclic strength and stiffness have therefore been investigated with respect to the effect of initial anisotropic consolidation. The compressibilities during postcyclic recompression were similar to those for isotropic consolidation. Samples with a greater initial anisotropy had less volumetric strain but larger axial strains during postcyclic drainage. Under stress reversal conditions failure occurred as a result of the development of double amplitude cyclic strains, whereas under nonreversal conditions compressive axial plastic strain was accumulated. Postdrainage second loading cyclic strength increased with increasing anisotropy. For isotropically consolidated samples failure under reversal cyclic loading resulted in a weaker soil structure even after postcyclic reconsolidation. 相似文献
992.
Toru Araki 《Information Processing Letters》2007,104(3):86-90
In a digraph G, a vertex u is said to dominate itself and vertices v such that (u,v) is an arc of G. For a positive integer k, a k-tuple dominating set D of a digraph is a subset of vertices such that every vertex is dominated by at least k vertices in D. The k-tuple domination number of a given digraph is the minimum cardinality of a k-tuple dominating set of the digraph. In this letter, we give the exact values of the k-tuple domination number of de Bruijn and Kautz digraphs. 相似文献
993.
Hamiltonian laceability of bubble-sort graphs with edge faults 总被引:1,自引:0,他引:1
It is known that the n-dimensional bubble-sort graph Bn is bipartite, (n − 1)-regular, and has n! vertices. We first show that, for any vertex v, Bn − v has a hamiltonian path between any two vertices in the same partite set without v. Let F be a subset of edges of Bn. We next show that Bn − F has a hamiltonian path between any two vertices of different partite sets if ∣F∣ is at most n − 3. Then we also prove that Bn − F has a path of length n! − 2 between any pair of vertices in the same partite set. 相似文献
994.
In this study, a pilot-scale plant was built to examine the practicality of producing biogas from seaweeds, widely available in Japan. Laminaria sp. and Ulva sp. seaweeds were mixed with other organic waste (milk) and used as fermentation materials. Though quantities and ratios of the materials were varied, the ratio of generated methane to input chemical oxygen demand (COD) was largely stable (0.2–0.3 m3 methane/kg COD) and the organic acid concentration in the methane fermentation solution was low (< 1200 ppm) during prolonged operation. These findings indicate that stable methane fermentation was achieved and that mixing with other organic material was effective in suppressing fluctuations in material amounts caused by the variable supply of seaweeds. Our results demonstrate the practical feasibility of biogas generation using seaweeds. 相似文献
995.
Metallurgical and Materials Transactions B - The recovery of platinum group metals (PGMs) from spent automobile catalysts is a difficult process because of their relatively low contents in the... 相似文献
996.
In-situ experiments on the Ni/Al2O3 interface reaction were carried out with a high temperature X-ray diffractometer capable of measuring the X-ray diffraction pattern in 1–2 s using an imaging plate. The kinetic formation processes of the interface reaction layer were measured by short-period exposure experiments with a high temperature X-ray diffractometer. NiAl2O4 was formed at the Ni/Al2O3 interface from 1468 K to 1673 K in air. The formation of NiAl2O4 obeyed the parabolic rate law. The value of the activation energy suggests that the diffusion of Al through NiAl2O4 controls the rate of formation. The results of thermal expansion coefficient measurements suggest that when a sample is cooled to room temperature, the magnitude of the stress on the Al2O3 owing to NiAl2O4 is smaller than that caused by NiO. 相似文献
997.
Parit Kanjanavirojkul Nguyen Ngoc Mai-Khanh Tetsuya Iizuka Toru Nakura Kunihiro Asada 《Analog Integrated Circuits and Signal Processing》2018,95(3):457-465
Hierarchical temporal memory (HTM) is a neuromorphic algorithm that emulates sparsity, hierarchy and modularity resembling the working principles of neocortex. Feature encoding is an important step to create sparse binary patterns. This sparsity is introduced by the binary weights and random weight assignment in the initialization stage of the HTM. We propose the alternative deterministic method for the HTM initialization stage, which connects the HTM weights to the input data and preserves natural sparsity of the input information. Further, we introduce the hardware implementation of the deterministic approach and compare it to the traditional HTM and existing hardware implementation. We test the proposed approach on the face recognition problem and show that it outperforms the conventional HTM approach. 相似文献
998.
Toru Noguchi Ken-ichi Niihara Keiichi Kawamoto Masanori Fukushi Hiroshi Jinnai Ken Nakajima Morinobu Endo 《应用聚合物科学杂志》2021,138(22):50512
Polyamide 66 (PA66) nanocomposites were prepared by compounding carbon nanotubes (CNTs) using an elastic high-shear kneading method, and the mechanism to understand their excellent properties was verified. In addition, we developed a microwave heat treatment that increases toughness quickly and at low cost. By combining 6.6 vol% or more of CNTs, PA66 with improved mechanical properties, such as higher elastic modulus and yield strength, was achieved, making it possible to obtain a composite having excellent high-temperature characteristics that does not melt even at a temperature above the melting point. These effects appeared to be due to defibration of CNT aggregates and isolation and dispersion in PA66. A lamellar crystal of PA66 grows around the CNT, forming an interphase. The higher performance appeared to be attributable to a continuous three-dimensional structure in which CNTs are bound via the interphase, and the improvement of the elastic modulus of the composite material was tentatively ascribed to a Halpin-Tsai model in which the size of the unit cell of the three-dimensional structure is introduced. The resulting CNT/PA66 composite materials are superior not only in performance but also in price. 相似文献
999.
Naoto Tomite Yukitaka Arai Yoshimichi Ohki Toru Hinata Masakazu Washio 《IEEJ Transactions on Electrical and Electronic Engineering》2015,10(3):237-241
Five typical insulating polymers and a carbon‐loaded polyethylene were irradiated with 200‐keV electrons, and the space charge distributions remaining in the polymers were measured. When the polymer film is short‐circuited after irradiation, the amount of space charge gradually decreases monotonically. By analyzing such decay profiles, it becomes clear that the decay of the charges remaining after the irradiation is governed by the conductivity of the polymer. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
1000.