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101.
In the present work, the increase in the basicity index of the slag system of the flux, represented by the ternary system of MnO–SiO2–CaO oxides, is evaluated. The increment of the basicity index is performed by the addition of CaO, keeping the MnO/SiO2 percentage relation of the system constant, in order to evaluate the behaviour of the chemical composition resulting from the metal deposited by SAW. As a result, it is possible to intensify the Mn transfer to the deposited metal and at the same time attenuate that of the Si, S, P and the carbon remains basically unalterable. All this makes it possible, in combination with low-manganese wire, to obtain similar results to those obtained with fluxes of lower basicity in combination with medium manganese wires. 相似文献
102.
Koh Matsumoto Kazutada Ikenaga Jun Yamamoto Kazuki Naito Yoshiki Yano Akinori Ubukata Hiroki Tokunaga Tadanobu Arimura Katsuaki Cho Toshiya Tabuchi Akira Yamaguchi Yasuhiro Harada Yuzaburo Ban Kousuke Uchiyama 《半导体学报》2011,32(1):21-23
Growth rate has a direct impact on the productivity of nitride LED production.Atmospheric pressure growth of GaN with a growth rate as high as 10μm/h and also Al0.1Ga0.9N growth of 1μm/h by using 4 inch by 11 production scale MOVPE are described.XRD of(002) and(102) direction was 200 arcsec and 250 arcsec, respectively.Impact of the growth rate on productivity is discussed. 相似文献
103.
A method to determine direct‐ and quadrature‐axis inductances of permanent magnet synchronous motors
Shu Yamamoto Takashi Kano Yoshihiro Yamaguchi Takahiro Ara 《Electrical Engineering in Japan》2010,171(3):41-50
The equivalent circuit constants of permanent magnet synchronous motors are needed in the calculation of operation characteristics, construction of a control system, etc. These constants can be computed from the data on structural form and materials. However, measurements are necessary to obtain highly precise values. Methods for measurement of the d‐ and q‐axis inductances can be roughly divided into rotational and standstill methods. The standstill methods have the advantage that they are easy to carry out. However, it is difficult to consider magnetic saturation and distortion of the change in the armature winding inductance. The accuracy of the standstill method can be improved if these effects can be readily taken into account. This paper describes a standstill method for measuring accurate d‐ and q‐axis synchronous inductances of permanent magnet synchronous motors. By utilizing the fact that the EMF interference terms in the motor voltage equation considering the distortion of the inductance change are equal to zero when the rotor is in a specific position, the proposed method determines the inductances considering both magnetic saturation and inductance distortion effects from simple off‐line standstill testing. In addition, this method is capable of taking cross‐magnetic saturation into account when used with the necessary testing equipment. The proposed method was implemented on a 0.4‐kW interior permanent magnet synchronous motor with concentrated stator winding. The validity of the proposed method was demonstrated by comparing the measured and calculated results of the no‐load and on‐load characteristics. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(3): 41–50, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20969 相似文献
104.
Micafungin (FK463), a novel water-soluble echinocandin-like lipopeptide, exerted fungicidal action toward growing cells of Candida albicans at concentrations of 0.1 microg ml(-1) or above. The drug at these levels induced osmotically fragile cells and the resulting fungicidal effect was partially reversed when cultures were grown in the presence of an osmotic stabilizer. Candida cells incubated with fungicidal concentrations of micafungin gradually increased in size and/or became deformed. An electron microscopic study of such micafungin-treated cells revealed morphological alterations in the cell wall; deformation in contour, abnormal septum formation and decrease in thickness of the intermediate layer of the cell wall were prominent. In addition, the structure of cell membranes as well as of membranous cytoplasmic organelles was slightly impaired. These data suggest that micafungin principally affects the normal formation of the cell wall in growing Candida cells. 相似文献
105.
Victor Efimov Ken Obara Daigo Ueno Akira Yamaguchi Hidehiko Ishimoto 《Journal of Low Temperature Physics》2002,126(1-2):121-126
The behaviour of
4
He impurities has been investigated through positive ion mobility measurements in liquid
3
He at milliKelvin temperatures. In spite of the enormous surface area of the cell, the influence of
4
He lasted for hundreds of hours at temperatures of 20 mK. However below 10 mK, the
4
He impurities were quickly frozen out on the cell walls and we were free from the impurity problem. Nevertheless the multiple ion signal occasionally appeared even at a few mK, although it disappeared for a number of ionization pulses. 相似文献
106.
Takada M Yamaguchi H Kitamura H Uchihori Y Fujitaka K 《Radiation protection dosimetry》2002,99(1-4):391-392
Microdosimetric measurements of 19, 32, 43, 55, and 65 MeV protons were carried out with the A-150-walled low pressure proportional counter (LPPC). The spectra are deconvoluted into three components, which are energy loss by directly incident protons, secondary electrons, and scattered protons and heavy charged particle (including protons) produced by proton nuclear reactions with the TE wall. Dose-mean lineal energies of protons are large as usual, because larger lineal energies by proton reaction events are affected. 相似文献
107.
In randomized clinical trials comparing treatment effects on diseases such as cancer, a multicentre trial is usually conducted to accrue the required number of patients within a reasonable period of time. The fundamental point of conducting a multicentre trial is that all participating investigators must agree to follow the common study protocol. However, even with every attempt having been made to standardize the methods for diagnosing severity of disease and evaluating response to treatment, for example, they might be applied differently at different centres, and these may vary from comprehensive cancer centres to university hospitals to community hospitals. Therefore, in multicentre trials there is likely to be some degree of variation (heterogeneity) among centres in both the baseline risks and the treatment effects. While we estimate the overall treatment effect using a summary measure such as hazard ratio and usually interpret it as an average treatment effect over the centre, it is necessary to examine the homogeneity of the observed treatment effects across centres, that is, treatment-by-centre interaction. If the data are reasonably consistent with homogeneity of the observed treatment effects across centres, a single summary measure is adequate to describe the trial results and those results will contribute to the scientific generalization, the process of synthesizing knowledge from observations. On the other hand, if heterogeneity of treatment effects is found, we should carefully interpret the trial results and investigate the reason why the variation is seen. In the analyses of multicentre trials, a random effects approach is often used to model the centre effects. In this article, we focus on the proportional hazards models with random effects to examine centre variation in the treatment effects as well as the baseline risks, and review the parameter estimation procedures, frequentist approach-penalized maximum likelihood method--and Bayesian approach--Gibbs sampling method. We also briefly review the models for bivariate responses. We present a few real data examples from the biometrical literature to highlight the issues. 相似文献
108.
The experience of an emotion considered to be culturally unique (i.e., Japanese Amae) was tested in the United States, where there is no word to describe the concept. North American and Japanese participants read scenarios in which a friend made an inappropriate request (Amae), made no request, or made the request to another friend. Both American and Japanese participants felt more positive emotion and perceived the requester as feeling closer to them in the Amae condition than in the other two conditions. However, Americans felt more in control when asked for a favor than when not asked, a pattern that did not emerge among the Japanese. Cultural specificity of hypocognized emotions is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
Hiroyasu Hotokezaka Noboru Aoyagi Yasuhiro Kawahara Noriko U. Yamaguchi Shinya Nagasaki Ken Sasaki Satoru Tanaka 《Microsystem Technologies》2005,11(8-10):974-979
Laser-induced breakdown spectroscopy (LIBS) has been applied for quantitative analysis of Al2O3, CaCO3 and MgO particles suspended in water. In the single elemental system, the plasma emission intensities of Al, Ca and Mg were linearly increased with concentration of elements in the range of 1.0×10?5–1.0×10?3 M, 1.0×10?4–2.0×10?3 M and 8.0×10?5 –4.0×10?3 M, respectively. We also investigated the concentration dependence of breakdown spectra for suspended mixtures of Al2O3, CaCO3 and MgO particles. The emission lines, such as Al I, Ca I, Ca II and Mg I, were appeared in the LIBS spectrum simultaneously, and each emission peak could be deconvoluted. The plasma emission intensities of Al, Ca and Mg in the multielemental system were also linearly increased with their concentrations in the range of 1.0×10?5–1.0×10?3 M, 1.0×10?4–2.0×10?3 M and 4.0×10?4–2.0×10?3 M, respectively. LIBS was found to be available for quantitative and qualitative measurement of the concentrations of Al2O3, CaCO3 and MgO particles suspended in water. The present results suggest that LIBS is a potentially useful tool for in-situ analysis on particles composition and concentrations for environmental monitoring by the wearable information equipments. 相似文献
110.
Large-scale molecular dynamics simulations with high acceleration energy cluster impact on a diamond surface are performed
in order to investigate the surface erosion process. A CO2 cluster of 960 atoms with different acceleration energy (10, 50 and 100 keV/cluster) impacts on the (1 1 1) surface of diamond
that consists of more than one million carbon atoms. A typical transient crater and two or three-layered shockwaves are formed
for 50 and 100 keV impacts while only small elastic deformation can be seen for 10 keV. The kinetic energy and the volume
of the crater are almost linear functions of the acceleration energy, but the erosion is only enhanced by the 100 keV impact.
A strong peak of CO appears in the size distribution of the evaporating clusters in that case.
Received: 10 August 2001/Accepted: 24 September 2001
This work was supported by Grant-in-Aid for JSPS Fellows (No.11-08826) from the Ministry of Education, Science, Sports and
Culture, Japan.
This paper was presented at the Fourth International Workshop on High Aspect Ratio Microstructure Technology HARMST 2001
in June 2001. 相似文献