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91.
开发了一种干式喷射隔热材料,其热导率与隔热板一样低.它正取代普通的隔热板,因它的安装方便,工作环境较好.另外,我们已开发了新的湿式喷射料体系,它效率高,工作环境好. 相似文献
92.
K Makino H Kuwahara N Masuko Y Nishiyama T Morisaki J Sasaki M Nakao A Kuwano M Nakata Y Ushio H Saya 《Canadian Metallurgical Quarterly》1997,14(20):2425-2433
We have cloned a cDNA for a novel human homolog of the Drosophila discs large (dig) tumor suppressor protein, termed NE-dlg (neuronal and endocrine dig). Northern blot analysis revealed that the gene is highly expressed in neuronal and endocrine tissues. Fluorescence in situ hybridization (FISH) and radiation hybrid mapping studies localized the NE-dlg gene to chromosome Xq13. We also found that the NE-dlg gene encoded a 100 kDa protein. Immunolocalization studies using an NE-dlg antibody showed that the protein tended to be expressed in non-proliferating cells, such as neurons, cells in Langerhans islets of the pancreas, myocytes of the heart muscles, and the prickle and functional layer cells of the esophageal epithelium. Proliferative cells, including various cultured cancer cell lines and basal cells in the esophageal epithelium, showed little expression of the NE-dlg protein. In addition, yeast two-hybrid screening and in vitro binding assays revealed that the NE-dlg interacted with the carboxyl-terminal region of the APC tumor suppressor protein. These data suggest that NE-dlg negatively regulates cell proliferation through its interaction with the APC protein. 相似文献
93.
Nowadays our society demands the reuse of industrial products. Then we should not only re-investigate the materials of products but also originate a new design method of industrial products. We have investigated the cellular structure by using abandoned paper, because the cell's shape can be proposed arbitrarily by folding a paper. As examples, we have proposed the structure constructed by connecting many folded cells formed in a hexagonal cross area. This structure will have characteristics such as almost high rigidity, high stiffness, crushing stress, relative insensitivity to the overall loss of stability. To estimate the characteristics of these structures, we must analyze the deformation in loading. When the structure with thin walls formed by paper is loaded, the shape of deformation is different from that of the metal, wall swells and does not maintain its flatness. Therefore, we cannot apply the traditional theory of elasticity for the analysis. In this paper, we propose a new estimation method by analyzing the swelling. 相似文献
94.
Proposes a simple automatic chromatic dispersion compensation system that can detect the zero-dispersion point of an installed fiber span. This technique realizes high sensitivity without requiring the system to be extensively modified. The alternating chirp signal, which is used as the zero-dispersion-detection signal, has alternating optical frequency shift. It can be generated simply by changing the input signals of multiplexer circuits and shifting the bias voltage of the LiNbO/sub 3/ modulator. This technique is shown to detect the zero-dispersion point in the range of -600 to +600 ps/nm by using the signal modulated at 10 GHz; automatic dispersion compensation is successfully demonstrated in a 20-Gb/s, 400-km transmission experiment in our laboratory. Compensation is also demonstrated in 281-km-installed dispersion-shifted fiber using a 20-GHz alternating chirp signal. 相似文献
95.
Radiocardiography has been widely used as a method for the quantification of cardiac output by applying the principle of the dye dilution method. This paper deals with an automatic analyzing system of radiocardiograms and a parameter estimation procedure using a linear system made up of four compartments with two time delays as a model of transport process in the blood circulatory system. The parameter estimation procedure named the window method in frequency domain is very effective for shortening the computing time and can be easily performed using a minicomputer. Parameter sensitivity analysis is also applied to study behavior of parameters on the model. Some analyzed results of radiocardiograms are shown and it is verified that the procedure is sufficiently useful and efficient for routine clinical use. 相似文献
96.
Satoshi Kaneco Nobu-hide HieiYue Xing Hideyuki KatsumataHisanori Ohnishi Tohru SuzukiKiyohisa Ohta 《Electrochimica acta》2002,48(1):51-55
The electrochemical reduction of CO2 on a Cu electrode was investigated in aqueous NaHCO3 solution, at low temperature. A divided H-type cell was employed, the catholyte was 0.65 mol dm−3 NaHCO3 aqueous solution and the anolyte was 1.1 mol dm−3 KHCO3 aqueous solution. The temperature during the electrolysis of CO2 was decreased stepwise to 271 K. Methane and formic acid were obtained as the main products. The maximum Faradaic efficiency of methane was 46% at −2.0 V and 271 K. The efficiency of hydrogen formation, a competing reaction of CO2 reduction, was significantly depressed with decreasing temperature. Based on the results of this work, the proposed electrochemical method appears to be a viable means for removing CO2 from the atmosphere and converting it into more valuable chemicals. The synthesis of methane by the electrochemical method might be of practical interest for fuel production and the storage of solar energy. 相似文献
97.
In this paper an overview is presented on R&D of medical imaging and image processing techniques in Japan during the last decade, focusing on case studies in the diagnosis of cardiac diseases.Various problems of image processing of left ventricular images obtained from x-ray, ultrasound and radionuclides are discussed. Also reviewed are boundary detection methods of left ventricular inner cavity and myocardium, analysis of left ventricular wall motion and various kinds of cardiac functions using conventional and newly developed methods, and display methods of these cardiac functions.Microcomputerized on-line image processing systems and a compound sector scan echocardiography using two probes developed for echocardiographic examinations are shown with some results in clinical applications.3-dimensional reconstruction methods of the left ventricle and other organs from multiple 2-dimensional images are shown with 3-dimensional shapes reconstructed from images by x-ray, ultrasound and radionuclides. Moreover, 3-dimensional functional images of the left ventricle are shown as well. Transferring the 3-dimensional consecutive left ventricular images during a cardiac cycle onto a CRT display under the control of a microprocessor, we can observe the pulsating 3-dimensional left ventricle on the CRT. 相似文献
98.
Theoretically studies the crosstalk penalty of coherent optical frequency division multiplexing systems by varying the intermediate frequency and the channel spacing. Results, applicable to ASK, PSK and CPFSK modulation formats, provide a quantitative criterion for designing a practical multichannel coherent lightwave system 相似文献
99.
100.
Tritium radioluminography has been applied to determine the hydrogen (H) diffusion coefficients in Ti50Cr50 and Ti40Cr60 alloys, both with two-phase structures of a body-centered cubic (bcc) phase and a Laves phase. Using radioluminography, H distributions in those phases have been observed, and H penetration profiles have been measured. The tritium diffusion coefficients in the Ti50Cr50 and Ti40Cr60 alloys have been successfully determined by analyzing the tritium penetration profiles to be 3.3±0.3 × 10?12 and 1.4±0.1×10?12 m2/s, respectively. These values suggest that the H diffusion in the Laves phase is slower than that in the bcc phase. It is also suggested that H diffuses by short-circuiting diffusion through the interface between the bcc phase and the Laves phase. 相似文献