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991.
Bovine immunoglobulins (IgG1 type) have been isolated from colostral whey. Hydrolysis by pronase, trypsin and (or) chymotrypsin yield several glycopeptides structural studies of which lead to the following results. 1. IgG1 colostral immunoglobulins possess two glycan moieties which are linked to the peptidic chain by an N-(beta-aspartyl)-N-acetylglucosaminylamine bound. 2. The peptidic sequence around the linkage region has been determined by classical methods and is as follows: Thr-Lys-Pro-Arg-Glu-Glu-Gln-Phe-Asn(Glycan)-Ser-Thr-Tyr-Arg. 3. The following procedures: partial acidic hydrolysis, periodic oxidation, hydrazinolysis-nitrous deamination, methylation and use of specific glycosidases allowed us to determine the structure of the glycan moieties which fit with the general following scheme: (see article) Thus they could be related to the general glycan structure so-called of "N-acetyllactosamine type" because they possess the pentasaccharidic core common to numerous glycoproteins Man alpha 1 leads to [Man alpha 1 leads to 6] Man beta 1 leads to 4 GlcNAc beta 1 leads to 4 GlcNAc beta 1 leads to Asn on which are conjugated 2 N-acetyllactosamine residues. Besides they present a microheterogeneity which is due to the varying number of additional N-acetylneuraminic acid and fucose residues. 4. These structures are compared to various immunoglobulin structures proposed by others: bovine serum IgG and human serum IgG, IgE and IgA. 相似文献
992.
Using the colorant proteic complex labell with Tc-99 m. we visualize--by the first time--the carotideal glomus in the human in 6 volunteers and one patient with tumor. The results are very encorageous: the method was simple and safe (one single dose endovenously) and hardless (no radiotoxicity presents in 3 months of clinical and laboratory controls) and there is a good visualization by scan of carotideal bodies "in vivo", in human being. We think this new method and labell compound could be useful in research and medical diagnoses. 相似文献
993.
J. M. Chappé J. Gavoille N. Martin J. Lintymer J. Takadoum 《Journal of Materials Science》2006,41(17):5639-5645
Dc reactive sputtering was successfully implemented to deposit titanium oxynitride thin films using a titanium metallic target, argon, nitrogen and water vapour as reactive gases. The nitrogen partial pressure was kept constant during every deposition whereas that of the water vapour was systematically changed from 0 to 0.1 Pa. The study aims at comparing the structural and mechanical properties of the coatings deposited at room temperature (293 K) and at 673 K. Surface morphology of the film was examined by atomic force microscopy and showed different aspects according to the growth temperature. Topography mainly depends on the amount of water vapour introduced during the deposition process. Some significant changes of the crystallographic structure, due to the high substrate temperature were correlated with the evolution of the surface aspect and roughness parameters. Determination of the phase occurrence by X-ray diffraction was also carried out and appeared to be a significant parameter in understanding the evolution of mechanical properties like nanohardness (H
n) and Young’s modulus (E). H
n and E values obtained by nanoindentation ranged from 16.5 to 7 GPa and from 240 to 100 GPa, respectively. For both temperatures, mechanical properties of titanium oxynitride thin films were notably reduced as a function of the water vapour supply, especially for partial pressures higher than 4 × 10−2 Pa. These mechanical behaviours were correlated and discussed with the phase occurrence and the amorphous structure of titanium oxynitride thin films. 相似文献
994.
O. Bretcanu S. Spriano C. Brovarone Vitale E. Verné 《Journal of Materials Science》2006,41(4):1029-1037
Ferrimagnetic glass-ceramics could be used for magnetic induction hyperthermia. This technique is utilised for the destruction
of solid neoplastic diseases by application of an alternating magnetic field. Biocompatible ferrimagnetic materials could
be easily incorporated into a tumour and could generate heat mainly by hysteresis loss.
A ferrimagnetic glass-ceramic in the system SiO2–Na2O–CaO–P2O5–FeO–Fe2O3 has been prepared by melting of the coprecipitation-derived raw materials. This glass-ceramic contains a unique crystalline
phase, magnetite, embedded in an amorphous matrix. Magnetite crystals precipitate during cooling from melting temperature.
This glass-ceramic would no longer require any nucleation and growth thermal treatment, since the maximal quantity of magnetite
crystals was produced during cooling. The average unit-cell parameter, crystallite size of magnetite, and the quantitative
ratio of the crystallographic phases in the glass-ceramic samples were evaluated using two different methods. Similar results
were obtained with both methods. The magnetite crystals are about 50 nm in dimensions. The samples contain 45 wt% of magnetite,
homogeneously distributed in the amorphous residual matrix.
The as prepared glass-ceramic has a saturation magnetisation of 34 A·m2/kg and a coercive force of 6.7 kA/m. The estimated magnetic loss/cycle under the magnetic field up to 796 kA/m is around
1.45 mJ/g. The specific power loss of this glass-ceramic under a magnetic field of 40 kA/m and a frequency of 440 kHz is 25 W/g.
This material showed a bioactive behaviour, as after 2 weeks of soaking in a simulated body fluid the formation of a hydroxylapatite
layer on their surface was observed. This feature makes it also suitable for bone cancer. 相似文献
995.
In this study, an experimental study was carried out to examine the effect of different clearances on smooth-sheared depth, burr height and blanking force. Aluminium sheet metals with 0.8, 1, and 1.5 mm thicknesses were used in the experiments. These experiments were carried out in circular blanking dies to 6, 8, 10, and 12 mm diameters. Six different clearances (0.009, 0.064, 0.12, 0.175, 0.231 and 0.287 mm) were used for every material and diameter. The results of the experiment show that burr, smooth-sheared and punch force is strongly related to the clearance value. The results are in agreement with the results of previous theoretical and experimental work in the literature. 相似文献
996.
High conductivity and transparent ZnO:Al films prepared at low temperature by DC and MF magnetron sputtering 总被引:2,自引:0,他引:2
C. Guillén 《Thin solid films》2006,515(2):640-643
Aluminum-doped zinc oxide thin films have been deposited by DC and MF magnetron sputtering from a ceramic oxide target in argon atmosphere without direct heating of the substrates. The samples were prepared at different predetermined conditions of input power or discharge voltage and the influence upon electronic, optical, and microstructural properties has been investigated. The as-deposited layers show low resistivity, such as 9 × 10− 4 Ω cm minimum for DC excitation and 1.2 × 10− 3 Ω cm for MF mode, with growth rates up to 130 nm/min, and resulting substrate temperatures always below 200 °C. Low resistivity of the films is combined with high transmission, 85-90% in the visible wavelength range (400-800 nm). A strong (002) texture perpendicular to the substrate has been found, with lower strain for DC than for MF sputtering. 相似文献
997.
Besides space laboratories for in-orbit experimentation, Earth based facilities for laboratory experimentation are of paramount importance for the enhancement on liquid bridge knowledge. In spite of the constraints imposed by simulated microgravity (which force to work either with very small size liquid bridges or by using the Plateau tank technique, amongst other techniques), the availability and accessibility of Earth facilities can circumvent in many cases the drawbacks associated with simulated microgravity conditions. To support theoretical and in orbit experimental studies on liquid bridges under reduced gravity conditions, several ground facilities were developed at IDR. In the following these ground facilities are briefly described, and main results obtained by using them are cited. 相似文献
998.
999.
We try to reproduce experimental mobility curves in ultrathin silicon-on-insulator inversion layers using a Monte Carlo simulator
and a bulk model for the electron scattering with acoustic phonons. While it is possible to reproduce the experimental behavior
for the thicker samples, the electron mobility is strongly overestimated when the thinnest samples are considered. The mobility
curves for the thinnest samples can be reproduced using the same model if the deformation potential parameter increases as
the silicon thickness decreases. This fact shows that acoustic phonons are also confined in ultrathin silicon on insulator
layers. We then study confined phonons in single and three layer structures in order to give a physical motivation to the
increase of acoustic phonon scattering rate for in ultrathin silicon layers. 相似文献
1000.
Guillermo de Len Adams Pere Grima Cintas Xavier Tort‐Martorell Llabrs 《Quality and Reliability Engineering International》2006,22(7):803-810
When analysing the effects of a factorial design, it is customary to take into account the probability of making a Type I error (the probability of considering an effect significant when it is non‐significant), but not to consider the probability of making a Type II error (the probability of considering an effect as non‐significant when it is significant). Making a Type II error, however, may lead to incorrect decisions regarding the values that the factors should take or how subsequent experiments should be conducted. In this paper, we introduce the concept of minimum effect size of interest and present a visualization method for selecting the critical value of the effects, the threshold value above which an effect should be considered significant, which takes into account the probability of Type I and Type II errors. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献