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941.
PURPOSE: To search for changes in the presence and distribution of the cell-adhesion-related HNK-1 carbohydrate epitope after cataract extraction. METHODS: Twenty-five pseudophakic and two aphakic human autopsy eyes and, for comparison, one anterior subcapsular cataract obtained at surgery were studied with monoclonal antibodies (MAbs) HNK-1 and NC-1 to the HNK-1 epitope using the avidin-biotinylated peroxidase complex method. RESULTS: MAbs to the HNK-1 epitope constantly immunolabelled the inner connective tissue layer of the ciliary body in all pseudophakic and aphakic eyes studied. The distribution of the immunoreaction was similar to that reported for normal eyes. They also labelled the extracellular matrix in each of 18 plaques of secondary cataract on the posterior capsule, in each of 13 plaques at the rim of the capsular bag, and in the anterior subcapsular cataract. Bladder cells in each of 16 Soemmering's rings remained unlabelled. CONCLUSION: The distribution of the HNK-1 epitope in the ciliary body does not appreciably change after cataract extraction, although the accommodative demand of the eye is altered. Its presence in an anterior subcapsular cataract suggests that the epitope may be locally produced by lens epithelial cells also in secondary cataract. The epitope is associated with cell adhesion and migration, both of which may play a role in the pathogenesis of secondary cataract. 相似文献
942.
Membranoproliferative glomerulonephritis induced by portosystemic shunt surgery for non-cirrhotic portal hypertension 总被引:1,自引:0,他引:1
The liver and spleen both have important phagocytic functions and contain monocytes/macrophages which clear immune complexes. We describe here three patients who presented proteinuria and hematuria 7 to 13 years after portosystemic shunt surgery, which diverted portal venous blood to the systemic circulation. They had hematemesis and/or melena and underwent mesocaval shunt surgery and splenectomy in childhood because of non-cirrhotic portal hypertension with esophageal varices. Renal biopsy specimens revealed findings characteristic of membranoproliferative glomerulonephritis (MPGN) type I. Immunohistologically, these three cases were accompanied by a distinct IgA deposition along with a marked C3 deposition. The IgA observed in these three cases contained not only IgA1 but also IgA2, which is the predominant form of mucosal IgA. On the other hand, of 20 patients with idiopathic MPGN type I with IgA deposition (n = 20), only two were positive for IgA2, and the distribution was focal and segmental. Our study shows that MPGN type I may have developed secondary to portosystemic shunt. This secondary form of MPGN type I may be caused by a reduced clearance of immune complexes in the liver and their deposition in the glomerulus, since a portosystemic shunt routes portal venous blood from the intestinal tract directly to the systemic circulation. 相似文献
943.
Ikeuchi K. Sato K. 《IEEE transactions on pattern analysis and machine intelligence》1991,13(11):1139-1153
The authors discuss a method of recovering reflectance properties of a surface from a range image given by a range finder and a brightness image given by a standard TV camera. The Torrance-Sparrow model is used for the reflectance model. The model consists of the Lambertian and specular components: its reflectance properties consist of the relative strength between the Lambertian and specular components and specular sharpness as well as light source direction. An iterative least square fitting method is used to obtain these parameters based on the range and brightness images. An input image is segmented into four different parts using the parameters: Lambertian reflection, specular reflection, interreflection, and shadow part. The authors also reconstruct ideal images that consist of only Lambertian or specular reflection 相似文献
944.
Railway Engineering Science - Three-dimensional compressible flow simulations were conducted to develop a Hyperloop pod. The novelty is the usage of Gamma transition model, in which the transition... 相似文献
945.
946.
This paper describes a power-efficient distributed TDMA slot scheduling algorithm which the slot allocation priority is controlled by distance measurement information in details. In our former proposed scheme, L-DRAND+, an extension of Lamport’s bakery algorithm for prioritized slot allocation based on the distance measurement information between nodes and a packet-based transmission power control had been applied. In this paper, we propose its enhanced scheme with a weighted rule control and state machines refinements of L-DRAND+, named L-DRAND++. This aims at the achievement of media access control methods which can construct a local wireless network practically by limiting the scope, and eliminate the redundant power consumption in the network. The proposed scheme can be shown as a possible replacement of DRAND algorithm for Z-MAC scheme in a distance-measurement-oriented manner. In addition, to evaluate the ordered node sequence determined by the algorithm, node sequence metric is proposed. By using the metric, we can evaluate protocol behaviors according to the environmental situation around the node. 相似文献
947.
Shoya Uchida Akihiro Sato Mamiko Inamori Yukitoshi Sanada Mohammad Ghavami 《Wireless Personal Communications》2014,79(2):987-1002
Overlapped FFT has been proposed as a signal detection scheme in dynamic spectrum access to reduce the variance of the noise and improve the detection probability. However, the improvement of the detection probability in the conventional overlapped FFT is bounded with the upper limit of the overlap ratio. This paper proposes a new overlapped FFT scheme using additional frames. In the proposed scheme, in addition to the original FFT frames, new frames that consist of multiple subframes with non-continuous samples are constructed and included. It can realize the increase of the number of the FFT frames and the improvement of the detection probability compared with the conventional scheme. Numerical results through computer simulation show that the proposed scheme improves the detection probability by up to 0.07. On indoor channel models the proposed scheme also improves the detection probability. In addition, it is clarified that as the delay spread increases the detection probability reduces due to the correlation between the frames. 相似文献
948.
S. Okada D. A. Bennett W. B. Doriese J. W. Fowler K. D. Irwin S. Ishimoto M. Sato D. R. Schmidt D. S. Swetz H. Tatsuno J. N. Ullom S. Yamada 《Journal of Low Temperature Physics》2014,176(5-6):1015-1021
We are preparing for an ultra-high resolution X-ray spectroscopy of kaonic atoms using an X-ray spectrometer based on an array of superconducting transition-edge-sensor microcalorimeters developed by NIST. The instrument has excellent energy resolutions of 2–3 eV (FWHM) at 6 keV and a large collecting area of about 20 mm \(^2\) . This will open new door to investigate kaon-nucleus strong interaction and provide new accurate charged-kaon mass value. 相似文献
949.
K. Takehara Y. Sato T. Tohei N. Shibata Y. Ikuhara 《Journal of Materials Science》2014,49(11):3962-3969
Dislocations are linear lattice defects in a crystalline solid. Since the unusual atomistic environment of the dislocation may greatly influence various material properties, control of the composition would offer more opportunities to obtain unique one-dimensional structures. In the present study, we have characterized the structure of dislocations in a low-angle tilt grain boundary of strontium titanate (SrTiO3). High-spatial resolution elemental mapping by electron energy loss spectroscopy combined with scanning transmission electron microscopy has enabled visualization of the enrichment of titanium (Ti) and the depletion of strontium (Sr) near the dislocation cores. The Ti enrichment and the Sr depletion have been observed at all of the dislocations, and the grain boundary is considered to be Ti excess. The extra Ti ions are located on the positions different from the normal perovskite lattice, suggesting that the local structure is largely reconstructed. It has been proposed that tensile strain at the dislocations may be a cause of the Ti enrichment. 相似文献
950.
Degradation mechanism of H2 permselectivity under atmosphere of steam/N2 = 3 at 773 K was investigated among amorphous silica membranes on γ-Al2O3-coated α-Al2O3 or Ni-doped γ-Al2O3-coated α-Al2O3 synthesized by counter diffusion chemical vapor deposition. Helium and H2 permeance drastically decreased during the first few hours of hydrothermal exposure. On the other hand, N2 permeance fluctuated during hydrothermal treatment in silica membrane on γ-Al2O3-coated α-Al2O3. The degree of N2 permeance change depended on the hydrothermal stability of the intermediate layer. Hydrogen permselectivity was affected by both the densification of amorphous silica and the sintering of the intermediate layer during hydrothermal exposure. 相似文献