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121.
122.
Hisatake Kondo 《Microscopy research and technique》1984,1(3):227-241
A simple and reliable method to make resinless sections for electron microscopy was recently developed by using polyethylene glycol (PEG) as a transient embedding media. In this paper the practical procedure of this PEG method is described in detail. Normal ultrastructure of several types of in-situ cells in resinless sections is demonstrated. The cytoplasmic matrix of all in-situ cells examined is revealed to consist of the microtrabecular lattice. A result from application of this technique to immuno-electron microscopy is also illustrated. This method is shown to have potential in overcoming the problem of intracellular penetration of macromolecular antibodies. Several artifacts caused by failures in specimen preparations are displayed. The real or artifactual nature of the microtrabecula is briefly discussed. 相似文献
123.
P. Kubisa L. S. Corley T. Kondo M. Jacovic O. Vogl 《Polymer Engineering and Science》1981,21(13):829-838
Samples of chloral homopolymers and copolymers with aromatic isocyanates of high chloral content were prepared by cryotachensic polymerization as films of 0.1 to 5 mm thickness. Thermal, mechanical, and electrical properties of these polymers were measured. Polychloral is unlike most other linear polymers as it does not show any melting or glass transition below 220°C, at which temperature the polymer starts to degrade by depolymerization to monomer. The polymer is of moderate crystallinity and shows properties characteristic of engineering plastics. 相似文献
124.
H. Tsukada Z. Asaki T. Tanabe Y. Kondo 《Metallurgical and Materials Transactions B》1981,12(3):603-609
. A rectangular plate of mixed copper-iron sulfide composed of bornite (Cu5FeS4) and troilite (FeS) was oxidized in an O2-Ar mixed gas stream at 1023 to 1123 K. At the start of the oxidation, iron was preferentially oxidized with the rapid formation
of a dense Fe3O4 layer of about 10 μm thickness on the sample surface, without the evolution of SO2 gas. Following this reaction, layers of both Fe3O4 and Fe2O3 grew on the sulfide surface in accordance with the parabolic rate law. The diffusion of iron through the oxide layers was
assumed to control the oxidation rate during this stage. The effect of oxygen partial pressure on the parabolic rate constants
was minor and an apparent activation energy of 126 kJ/mol was obtained. During the later stages of the reaction, when the
sulfur activity in the inner sulfide core increased, the oxidation proceeded irregularly to the interior of the remaining
sulfide with the formation of a porous oxide and the evolution of gaseous SO2. The remaining sulfide core was found to be
a mixture of bornite (Cu5FeS4) and djurleite (Cu1.96S).
H. TSUKADA, former Graduate Student at Kyoto University 相似文献
125.
Computed tomography (CT) is increasingly employed in orthodontic treatment. One of the most successful applications is in dental implantology, in which an artificial root is surgically inserted into the jawbone to provide anchorage for a dental prosthesis. For successful implant surgery, it is crucial to locate internal structures such as the inferior alveolar nerve canal (IAC). This paper presents a computerized technique for extracting the IAC. To facilitate the extraction, we first generate panoramic CT images (panoramics) by reformatting the original CT images. The panoramics are a series of cross-sectional images along curved planes through the mandible (lower jawbone). Hollow canals are subsequently detected by analyzing the voxel intensities and 3-D gradient orientations in the panoramics. The axis of the IAC is then traced out by a novel 3-D line-tracking technique. The method is effective for extracting the IAC despite the open structure of the surrounding bone. 相似文献
126.
In learning machines the key problem is to determine weight vectors satisfying linear inequalities. In two-category classification only one weight is needed, but in multicategory classification the weight vectors which have to be found are as many as the number of pattern classes. The letter shows that, for linear machines, it is necessary to find only one weight vector, which the authors call the multiweight, by applying the steepest descent method in a learning algorithm. 相似文献
127.
S Iwasa C Kitada I Yoshida K Kondo M Hori M Fujino 《Canadian Metallurgical Quarterly》1981,89(4):1091-1099
A highly specific enzyme immunoassay for determining hCG was established by using beta-D-galactosidase as label. In order to increase the specificity of the assay, an antiserum against whole hCG was purified on a column of hCG beta carboxyl-terminal peptide (residues 123-145) covalently linked to Sepharose 4B. The antibody (N101S) thus prepared showed a weak cross-reactivity with human LH in an assay using hCG-enzyme conjugate, but the slight cross-reactivity was virtually avoided when an hCG beta carboxyl-terminal peptide was used as a peptide in the enzyme conjugate. N101S antibody was compared with antiserum (B1B) directed against a carboxyl-terminal peptide (123-145). In hCG measurement N101S gave about 30 times higher sensitivity than B1B, although the former antibody was less sensitive to carboxyl-terminal peptides of hCG beta. The enzyme immunoassay using a combination of N101S antibody and a carboxyl-terminal peptide (130-145)-enzyme conjugate was able to detect as little as 0.25 mIU of hCG without the interference of LH. The performance and validity of this assay were comparable to those of conventional radioimmunoassay. 相似文献
128.
Experimental exploration of discrepancies in F-number correlation of flammability limits 总被引:3,自引:0,他引:3
Flammability limits measurement has been made by ASHRAE method for some 20 kinds of combustible gases and vapors. These compounds have been selected mainly because the literature values of flammability limits are not consistent with the F-number calculated ones [J. Hazard. Mater. A 82 (2001) 113]. As a result, it has been found that the newly obtained values of flammable range are classified into three groups. For the first group of compounds, the present values agree well to the literature values. For the second group, the present values do not agree to the literature values but agree with the calculated ones. For the third group ones, the present values neither agree to the literature values nor to the calculated ones. There are 4, 13, and 6 compounds in the respective groups. 相似文献
129.
Chunqing?HeEmail author Takenori?Suzuki Eisaku?Hamada Hitoshi?Kobayashi Kenjiro?Kondo Victor?P.?Shantarovich Yasuo?Ito 《Materials Research Innovations》2003,7(1):37-41
Polymer structures have been investigated using positron annihilation lifetime spectroscopy (PALS) with a slow positron beam
as well as a conventional radioactive source (22Na). The properties of the free volume holes near the polymer surface were studied as a function of the positron implantation
energy. The longest lifetime was associated with ortho-positronium (o-Ps) annihilation in the free volume holes. In polytetrafluoroethylene film, the lifetime of o-Ps was observed to decrease with increasing positron implantation depth, and a significant change in the o-Ps lifetime was found at a short distance (about 10 nm) from the surface, while its intensity increased. This result implies
that near the polymer surface the free volume holes become larger that in the bulk. The effect of temperature on the polymer
sub-surface layers was also studied. For high molecular weight polystyrene, the glass transition temperature for the sub-surface
was lower than that for the bulk and thermal expansion coefficient of the sub-surface layers was found to be larger than the
bulk value.
Electronic Publication 相似文献
130.
Air has been irradiated with high energy protons at the 12 GeV proton synchrotron to obtain the following parameters essential for the internal dose evaluation from airborne 11C produced through nuclear spallation reactions: the abundance of gaseous and particulate 11C, chemical forms, and particle size distribution. It was found that more than 98% of 11C is present as gas and the rest is aerosol. The gaseous components were only 11CO and 11CO2, and their proportions were approximately 80% and 20%, respectively. The particulate 11C was found to be sulphate and/or nitrate aerosols having a log-normal size distribution; the measurement using a diffusion battery showed a geometric mean radius of 0.035 micron and a geometric standard deviation of 1.8 at a beam intensity of 6.8 x 10(11) proton.pulse-1 and an irradiation time of 9.6 min. By taking the chemical composition and particle size into account, effective doses both from internal and from external exposures per unit concentration of 11C were calculated for various room sizes. The values can be used to evaluate the effective dose from the airborne 11C produced in the accelerator tunnels. 相似文献