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111.
Ebara Y. Koizumi T. Sone H. Nemoto Y. 《Components and Packaging Technologies, IEEE Transactions on》2000,23(2):293-299
The authors have observed the relationship between waveform of electromagnetic noise and change of surface for opening Ag-Pd electric contacts. In case of Ag-Pd electrodes, continuous noise is observed in the whole period of arc discharge in both current polarities. Fluctuations of are voltage and noise are large in the middle part of arc discharge duration. The noise decreases in the later half. The authors proposed a classification of noise waveforms and pattern of surface changes. As a result, patterns of noise waveform and changes of electrode surface at various circuit conditions are classified into three categories. In this paper, the authors showed the correlation between pattern of noise waveform and the change of electrode surface 相似文献
112.
113.
This paper proposes a CTI client/server coordination system exclusively for use with a smart phone. The system makes use of a CTI client, performing combined functions of a SIP phone and a Web browser. The proposed CTI client/server coordination system comprises SIP servers and Web servers, both of which are installed in enterprises, and CTI clients that run on smart phones in a mobile environment. Furthermore, the CTI clients perform the function of SIP phone by communicating with SIP servers. In addition, CTI clients can display telephone directories and logging of phone calls stored in Web servers. They can display screens of ordinary Web browsers. Here, one might switch between a SIP phone function and a Web communication screen with merely a single touch of the tab key. Consequently, smart phones in the mobile environment make it possible to conduct telephone meetings while browsing with a Web screen. 相似文献
114.
Naomitsu Tsuyuki Koshiro Koizumi Yasuhiro Umemura 《Journal of the American Ceramic Society》2007,90(1):225-229
Converter slag contains free lime (CaO) and unstable iron oxides (FeO, FeOOH) that may lead to expansive self-destruction. A typical industry practice for converter slag has been stabilization by steam curing and autoclaving; however, the stabilization can only reach the surface, and not the inside, of slag particles. A new method is proposed in this study to stabilize the converter slag by heating at a low temperature. After magnetic separation, specimens of converter slag were subjected to heating for 2 h at a temperature of 500°C, resulting in a decrease of free lime content irrespective of the particle size. This effect was attributed to the formation of Ca2 Fe9 O13 and complicated apatite groups owing to the heating. The iron oxides in the converter slag were analyzed by X-ray photoelectron spectra. It was found that after heating, the unstable FeO (wustite) content decreased and an oxidized α-Fe2 O3 (hematite) increased. This led to the prevention of the iron-induced expansion. The rate of heat liberation by the free lime in converter slag was smaller than that of the reagent CaO. This suggests that the presumed free lime is in a different form based on the Ca bond energy in the surface of slag particles. 相似文献
115.
Isao Ishii Shotaro Kamata Saki Ito Aya Shimonaga Maika Koizumi Maiko Tsushima Asumi Miura Tomoko Nagata Yuka Tosaka Haruka Ohtani Waka Kamichatani Noriyuki Akahoshi 《International journal of molecular sciences》2022,23(2)
Methionine (Met) is considered the most toxic amino acid in mammals. Here, we investigated biochemical and behavioral impacts of ad libitum one-week feeding of high-Met diets on mice. Adult male mice were fed the standard rodent diet that contained 0.44% Met (1×) or a diet containing 16 graded Met doses (1.2×–13×). High-Met diets for one-week induced a dose-dependent decrease in body weight and an increase in serum Met levels with a 2.55 mM peak (versus basal 53 µM) on the 12×Met diet. Total homocysteine (Hcy) levels were also upregulated while concentrations of other amino acids were almost maintained in serum. Similarly, levels of Met and Hcy (but not the other amino acids) were highly elevated in the cerebrospinal fluids of mice on the 10×Met diet; the Met levels were much higher than Hcy and the others. In a series of behavioral tests, mice on the 10×Met diet displayed increased anxiety and decreased traveled distances in an open-field test, increased activity to escape from water soaking and tail hanging, and normal learning/memory activity in a Y-maze test, which were reflections of negative/positive symptoms and normal cognitive function, respectively. These results indicate that high-Met ad libitum feeding even for a week can induce bipolar disorder-like disease models in mice. 相似文献
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117.
LiFePO4 as a cathode material for rechargeable lithium batteries was prepared by hydrothermal process at 170 °C under inert atmosphere. The starting materials were LiOH, FeSO4, and (NH4)2HPO4. The particle size of the obtained LiFePO4 was 0.5 μm. The electrochemical properties of LiFePO4 were characterized in a mixed solvent of ethylene carbonate and diethyl carbonate (1:1 in volume) containing 1.0 mol dm−3 LiClO4. The hydrothermally synthesized LiFePO4 exhibited a discharge capacity of 130 mA h g−1, which was smaller than theoretical capacity (170 mA h g−1). The annealing of LiFePO4 at 400 °C in argon atmosphere was effective in increasing the discharge capacity. The discharge capacity of the annealed LiFePO4 was 150 mA h g−1. 相似文献
118.
Lauwereyns Johan; Koizumi Masashi; Sakagami Masamichi; Hikosaka Okihide; Kobayashi Shunsuke; Tsutsui Ken-ichiro 《Canadian Metallurgical Quarterly》2000,26(3):352
To study the operation of selective attention in a conflict situation with automatic processes, we trained 4 Japanese macaques; (Macaca fuscata) extensively on a manual go/no-go task. The monkey had to discriminate either the color, shape, motion direction, or location of a visual stimulus. In each trial, the behavioral meaning of the relevant feature (go or no-go) could either be congruent or incongruent with irrelevant features of the same stimulus. Reaction times were slowed, and error rates increased when irrelevant stimulus features were incongruent with the required response. The effects were obtained when the monkey attended to the color, shape, or motion direction, but not when it attended to the location of the stimulus. The effects were cumulative so that the interference from 1 incongruent feature was smaller than that from 2 incongruent features. We propose that the present paradigm provides a behavioral analogue of the human Stroop effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
119.
Y. Minamino Y. Koizumi N. Tsuji M. Morioka K. Hirao Y. Shirai 《Science and Technology of Advanced Materials》2000,1(4):143
Diffusion of platinum element which increase protectivity of NiAl layer for hot corrosion and oxidation of Ni-base superalloys was investigated in NiAl compound with compositions of 43.7–51.9 at% Al at 1373–1673 K by the diffusion couple method. The diffusion coefficients, DPt, exhibit a large concentration dependence of valley type-shape; the DPt has the minimum value quite near the stoichiometric composition and it increases with deviation from the stoichiometry. On the other hand, the activation energy, Q, shows the maximum value near the stoichiometry. Q slightly decreases with Ni composition in Ni-rich side, while it decrease dramatically with Al composition in Al-rich side. Diffusion of platinum element in NiAl occurs mainly by the Triple defect mechanism at stoichiometry, by the anti-site atom bridge mechanism in considerably off-stoichiometry in Ni-rich side and by the next nearest neighbor-jump mechanism with constitutional Ni vacancies in quite off-stoichiometry in Al-rich side. 相似文献
120.
K Sawada K Koizumi T Tarumi H Takano M Ieko M Nishio Y Fukada T Yasukouchi M Yamaguchi T Koike 《Canadian Metallurgical Quarterly》1999,23(1):1-11
Extrapolation of animal data to assess pharmacokinetic parameters in humans is an important tool in drug development. Allometric scaling has many proponents, and many different approaches and techniques have been proposed to optimise the prediction of pharmacokinetic parameters from animals to humans. The allometric approach is based on the power function Y = aWb, where the bodyweight of the species is plotted against the pharmacokinetic parameter of interest on a log-log scale. Clearance, volume of distribution and elimination half-life are the 3 most frequently extrapolated pharmacokinetic parameters. Clearance is not predicted very well (error between predicted and observed clearance > 30%) using the basic allometric equation in most cases. Thus, several other approaches have been proposed. An early approach was the concept of neoteny, where the clearance is predicted on the basis of species bodyweight and maximum life-span potential. A second approach uses a 2-term power equation based on brain and body weight to predict the intrinsic clearance of drugs that are primarily eliminated by phase I oxidative metabolism. Most recently, the use of the product of brain weight and clearance has been proposed. A literature review reveals different degrees of success of improved prediction with the different methods for various drugs. In a comparative study, the determining factor in selecting a method for prediction of clearance was found to be the value of the exponent. Integration of in vitro data into in vivo clearance to improve the predictive performance of clearance has also been suggested. Although there are proponents of using body surface area instead of bodyweight, no advantage has been noted in this approach. It has also been noted that the unbound clearance of a drug cannot be predicted any better than the total body clearance (CL). In general, there is a good correlation between bodyweight and volume of the central compartment (Vc); hence, Vc does not face the same complications as CL. The relationship between elimination half-life (t 1/2 beta) and bodyweight across species results in poor correlation, most probably because of the hybrid nature of this parameter. When a reasonable prediction of CL and Vc is made, t 1/2 beta may be predicted from the equation t 1/2 beta = 0.693 Vc/CL. 相似文献