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891.
The three-dimensional fine architecture of the red pulp of human and animal spleens, which as fixed by a modified version of the arterial and venous pressure-loading perfusion fixation (AVPL perfusion fixation) method, is demonstrated by scanning and transmission electron microscopy. In the human spleen, changes in splenomegalias associated with hereditary spherocytosis and chronic portal hypertension are also introduced in addition to the normal architecture of the red pulp of spleens removed from patients with stomach cancer. The AVPL perfusion fixation of these spleens clearly visualized complicated three-dimensional fine architecture of the red pulp and provided much important information on in situ morphology and dynamic change of the terminal vascular bed, including venous pressure-dependent size change of the stomata and three-dimensional shapes of the capillary terminal, with positive proof of their opening into the cordal reticular tissue. In studies of the spleen associated with portal hypertension, the AVPL perfusion fixation is considered a necessary technique for analysis of the structural deviation closely relating to a very high venous pressure. 相似文献
892.
893.
The relationship between the permeation characteristics of an aqueous polymer solution and the asymmetric structure of cellulose nitrate membranes was investigated under various conditions. The conditions and mechanism of the formation of finger-like cavities in cellulose nitrate membranes are discussed in some detail. 相似文献
894.
895.
The polymerization of acrylonitrile and methyl methacrylate initiated by polyvinylamine-copper(II) chelate was studied in dimethylsulfoxide solution, in the presence and absence of carbon tetrachloride. For comparison, the dimeric chelate(1,3-diaminopropane-copper(II) chelate) was also chosen as an initiator. The initiation activity of the dimeric chelate was found to be higher than that of the polymeric chelate in dimethylsulfoxide solution, different from the cases in aqueous media. The dimeric chelate could initiate the polymerization of acrylonitrile effectively, even in the absence of carbon tetrachloride. 相似文献
896.
Growth of fibrous hydroxyapatite in the gel system 总被引:3,自引:0,他引:3
Kanichi Kamiya Toshinobu Yoko Katsuhisa Tanaka Yoshiaki Fujiyama 《Journal of Materials Science》1989,24(3):827-832
Hydroxyapatite (HAP) was prepared in the agar gel system, where Ca2+ ions were incorporated in the gel and PO
4
3–
solution was layered over the gel. When the concentration of Ca2+ was lower than 1.0 M and the initial solution Ca/P molar ratio was lower than about unity, fibrous HAP several centimetres to several tens of centimetres in length was grown upwards in the PO
4
3–
solution from the gel phase, while at the larger Ca2+ concentration and initial Ca/P molar ratio CaHPO4 · 2H2O (DCPD) in the form of gelatinous precipitate, particulate precipitates or needle-like crystals were preferred to HAP. The fibrous HAP was calcium deficient and composed of small elongated hollow ovals linked in a zigzag row. This was considered to be formed in the following manner. First, Ca2+ ions supplied through pores in the gel reacted with PO
4
3–
ions to form a small spherulite at the pore exit, then the spherulite was bloated and elongated by the osmotic pressure or capillary force until a part of the oval was broken for Ca2+ ions to be gushed out into the PO
4
3–
solution. The above two processes were repeated to form elongated hollow ovals linked to the preceding ones. 相似文献
897.
Yaqin Hu Katsuji Morioka Yoshiaki Itoh 《Journal of the science of food and agriculture》2010,90(3):370-375
BACKGROUND: Endogenous proteases, among them cysteine‐type proteases, are reported to contribute to gel disintegration, resulting in kamaboko of poor quality. Severe gel disintegration occurs in red bulleye surimi gel paste. The objective of this study was to clarify the participation of cysteine protease cathepsin L in the gel disintegration of red bulleye surimi. The surimi was made into kamaboko with and without cathepsin L inhibitors. To confirm its hydrolysis action, crude cathepsin L was also extracted and added to the surimi to make kamaboko. RESULTS: The gel strength of kamaboko obtained by both one‐step (50 °C, 2 h) and two‐step (50 °C, 2 h + 80 °C, 20 min) heating was very low in the absence of inhibitors. Protease inhibitors E‐64 and leupeptin were found to enhance the gel strength considerably. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed that the hydrolysis of kamaboko was promoted by crude cathepsin L and inhibited by E‐64 and leupeptin. The gel strength of two‐step heated kamaboko was increased from 12 to 110 and 130 g cm?2 by E‐64 and leupeptin respectively at a concentration of 0.2 g kg?1 surimi. CONCLUSION: Endogenous cathepsin L of red bulleye surimi participates in gel disintegration during kamaboko processing. It does so by degrading the myosin heavy chain of actomyosin and consequently hindering the gelation of red bulleye surimi. Copyright © 2009 Society of Chemical Industry 相似文献
898.
Kouhei Ebihara Jun Kikkawa Yoshiaki Nakamura Akira Sakai Gang Wang Matty Caymax Yasuhiko Imai Shigeru Kimura Osami Sakata 《Solid-state electronics》2011,60(1):26-30
We used X-ray microdiffraction (XRMD) to investigate the crystallinity and strain relaxation of Ge thin lines with widths of 100, 200, 500 and 1000 nm selectively grown on Si(0 0 1) substrates using a patterned SiO2 mask by chemical vapor deposition. The variations of the strain relaxation in the line and width directions were also investigated in Ge thin lines with a width of 100 nm. After growth, crystal domains with very small tilt angles were detected in Ge lines with all four line widths. The tilt angle range was larger in thinner Ge lines. After annealing at 700 °C, the formation of a single, large domain with a specific tilt angle was detected by XRMD for Ge thin lines with widths of 100 and 200 nm. These experimental results reflect the effects of SiO2 side walls around the Ge thin lines on crystallinity and strain relaxation of Ge. 相似文献
899.
Yoshiaki Kano Shigeo Morimoto Yoshinari Asano Yuji Enomoto 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(6):804-811
This paper presents an overview of the recent technical trends in permanent magnet synchronous motors (PMSMs), especially the rare earth (RE)‐less PMSMs that have been developed in Japan. The RE‐less PMSMs, along with PMSMs with reduced RE permanent magnets (PMs), PM‐assisted synchronous reluctance motors (PMASynRM) with ferrite PMs, spoke‐type interior PMSMs (IPMSMs) with ferrite PMs, and axial‐gap PMSMs with ferrite PMs, are reviewed. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
900.
Mixtures of C2H4---O2---CF3Cl and CH4---O2---CF3Cl, highly diluted with argon, were heated to the temperature range 1350–2200K behind reflected shock waves, and the additive effects of CF3Cl on OH*, CH*, and C2* emissions in the ethylene and methane combustion processes were examined by observing the delay time, and the intensities of OH*, CH*, and C2* emissions. It was found that, in ethylene combustion, the addition of CF3Cl prolonged the delay times to the maximum intensities, decreased the intensities of OH* and CH* emissions, and had little influence on that of C2* emission. However, in methane combustion, it was found that the addition of CF3Cl shortened the delay times to the maximum intensities and to the onset of ignition, increased the intensities of CH* and C2* emissions, and had little influence on that of OH* emission. 相似文献