全文获取类型
收费全文 | 1354篇 |
免费 | 27篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 57篇 |
综合类 | 3篇 |
化学工业 | 308篇 |
金属工艺 | 28篇 |
机械仪表 | 36篇 |
建筑科学 | 19篇 |
能源动力 | 48篇 |
轻工业 | 129篇 |
水利工程 | 2篇 |
无线电 | 96篇 |
一般工业技术 | 186篇 |
冶金工业 | 354篇 |
原子能技术 | 48篇 |
自动化技术 | 71篇 |
出版年
2023年 | 12篇 |
2022年 | 5篇 |
2021年 | 20篇 |
2020年 | 6篇 |
2019年 | 14篇 |
2018年 | 22篇 |
2017年 | 18篇 |
2016年 | 23篇 |
2015年 | 11篇 |
2014年 | 30篇 |
2013年 | 69篇 |
2012年 | 37篇 |
2011年 | 64篇 |
2010年 | 37篇 |
2009年 | 52篇 |
2008年 | 51篇 |
2007年 | 40篇 |
2006年 | 42篇 |
2005年 | 43篇 |
2004年 | 42篇 |
2003年 | 53篇 |
2002年 | 40篇 |
2001年 | 28篇 |
2000年 | 27篇 |
1999年 | 34篇 |
1998年 | 123篇 |
1997年 | 74篇 |
1996年 | 51篇 |
1995年 | 35篇 |
1994年 | 33篇 |
1993年 | 34篇 |
1992年 | 15篇 |
1991年 | 14篇 |
1990年 | 8篇 |
1989年 | 11篇 |
1988年 | 15篇 |
1987年 | 15篇 |
1986年 | 14篇 |
1985年 | 9篇 |
1984年 | 5篇 |
1983年 | 9篇 |
1982年 | 13篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1979年 | 14篇 |
1978年 | 5篇 |
1977年 | 13篇 |
1976年 | 17篇 |
1974年 | 5篇 |
1972年 | 6篇 |
排序方式: 共有1385条查询结果,搜索用时 15 毫秒
1.
Koji Morita Byung-Nam Kim Hidehiro Yoshida Keijiro Hiraga Yoshio Sakka 《Journal of the European Ceramic Society》2018,38(6):2588-2595
Carbon contamination from the carbon paper/dies during spark-plasma-sintering (SPS) processing was examined in the MgAl2O4 spinel. The carbon contamination sensitively changes with the heating rate during the SPS processing. At the high heating rate of 100 °C/min, the carbon contamination having organized structures occurred over almost the entire area from the surface to deep inside the SPSed spinel disk. In contrast, at the slow heating rate of 10 °C/min, the carbon contamination having disordered structures occurred only around the surface area. The carbon phases transform into high pressure CO/CO2 gases by post-annealing in air and lead to pore formation along the grain junctions. The pore formation significantly occurs at the high heating rate due to the large amount of the contaminant carbon phases. This suggests that if once the carbon contamination was formed in the materials, it is very difficult to remove the carbon phases from the materials. 相似文献
2.
3.
K Endo K Morita Y Uchiyama K Takada A Tsujimoto T Dohi 《Canadian Metallurgical Quarterly》1993,62(3):325-328
Influences of drug-induced manipulations of central serotonergic function on lidocaine- and pentylenetetrazol (PTZ)-induced convulsions were examined in mice. Agents that suppressed serotonergic transmission increased, whereas drugs that facilitated serotonin (5-HT) function decreased the incidence of lidocaine-induced convulsions. These treatments had similar influences on the incidence of PTZ-induced convulsions. Lidocaine (10(-5)-10(-3) M) reduced the stimulation evoked [3H]5-HT release from cortical slices, followed with an increased spontaneous [3H] overflow at higher concentrations. These results may suggest that brain 5-HT neurons are causally involved as inhibitory neurons in lidocaine-induced convulsions as in the case of PTZ-induced convulsions. 相似文献
4.
Boron removal by titanium addition in solidification refining of silicon with Si-Al melt 总被引:4,自引:0,他引:4
Takeshi Yoshikawa Kentaro Arimura Kazuki Morita 《Metallurgical and Materials Transactions B》2005,36(6):837-842
In order to effectively remove B from Si for its use in solar cells, a process involving B removal by solidification refining
of Si using a Si-Al melt with Ti addition was investigated. For clarifying the effect of Ti addition on B removal from the
Si-Al melt, TiB2 solubilities in Si-64.6 at. pct Al melt at 1173 K and Si-60.0 at. pct Al melt at 1273 K were determined by measuring the
equilibrium concentrations of B and Ti in the presence of TiB2 precipitates. The small solubilities of TiB2 in the Si-Al melt indicate the effective removal of B from the Si-Al melt by Ti addition. Further, solidification experiments
of Si-Al alloys containing B by Ti addition were performed, and the effect of Ti addition on the solidification refining of
Si with the Si-Al melt was successfully confirmed. 相似文献
5.
On‐Line Detection Of State‐Of‐Charge In Lead Acid Battery Using Radial Basis Function Neural Network
To realize a stable supply of electric power in an automobile, an accurate and reliable detection method of SOC (state‐of‐charge) in a lead acid battery is required. However the dynamics of the battery is very complicated. The characteristics of the battery greatly change due to its degradation. Moreover a automobile has many driving patterns, which are unknown beforehand. Thus it is not easy to detect the SOC analytically. In this paper, to overcome this problem, a new on‐line SOC detection method with a radial basis function neural network is proposed. In order to increase the detection accuracy of degraded batteries, physical values related to the degradation degree are used as input signal in the neural network. The detection accuracies for different sized batteries and various degradation states are investigated. 相似文献
6.
The absorption spectrum of poly(3-alkylthiophene) gel changes drastically in association with a volume instability upon changing the solvent composition and also the temperature. In the expanded state in chloroform and at high temperature, the photoluminescence is much enhanced compared with the shrunken state in ethanol and at low temperature. This gel chromism and anomalous luminescence are discussed in terms of the change of effective conjugation length induced by the steric hindrance and the dynamics of the photoexcited species. 相似文献
7.
8.
This paper presents a new method for power system planning which considers uncertainties of various system parameters as a part of the criterion function. The criterion function involves both the expected values of total system costs and the cost variances of different power plants. Previously, the authors proposed that these cost variances be evaluated from the existing power system plans in the form of the solutions to the inverse optimization problem, and then applied this procedure to the planning of power systems in Japan. However, because of the correlation between fuel and facility costs, the cost variances could not be determined as specific values. Here, to overcome this difficulty, the authors now introduce hydropower plants into the model as the so-called nonrisky elements and focus on the expenditure shares rather than the plant capacity shares. As a result, more reasonable results are obtained. This improved methodology is applied and the derived cost variances are shown. Further, using the resultant cost variances, the authors make Pareto-optimal power generation plans and demonstrate also the robustness of the method to price fluctuations. 相似文献
9.
Ikuro Morita 《Electrical Engineering in Japan》1992,112(3):171-181
The relationship between the magnetomotive force distribution of a three-phase induction motor and various cage rotor faults, such as broken bars and end rings, is discussed in detail. Search coil output and its harmonic components are analyzed to allow the determination of faults from the air-gap flux density. The results obtained in tests on a motor into which faults were intentionally introduced confirm the effectiveness of this method of analysis. 相似文献
10.
K. Nakano S. Tomiya M. Ukita H. Yoshida S. Itoh E. Morita M. Ikeda A. Ishibashi 《Journal of Electronic Materials》1996,25(2):213-216
Using electroluminescence (EL) topography and transmission electron microscopy (TEM), we investigated the nonluminescent regions
which form while current is being injected into ZnMgSSe/ZnSSe/ZnCdSe-based blue light emitters. Small dark spots were observed
just after turn-on and spread out forming rough nonluminescent triangles in the <100> directions in the EL image of the active
region. TEM studies showed that the small dark spots are pre-existing stacking faults originating at the substrate/epitaxial
layer interface. The nonluminescent triangles were found to be a dense region of dislocation dipoles and dislocation loops.
Each dipole was aligned along two <110> directions in the {111} planes. The Burgers vectors were of the type a/2<011> inclined
at 45° to the (001) junction plane. 相似文献