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991.
Highly crystalline TiO2 nanostructures were prepared through a facile inorganic acid-assisted hydrothermal treatment of hexagonal-structured assemblies
of nanocrystalline titiania templated by cetyltrimethylammonium bromide (Hex-ncTiO2/CTAB Nanoskeleton) as starting materials. All samples were characterized by X-ray diffraction (XRD) and transmission electron
microscopy (TEM). The influence of hydrochloric acid concentration on the morphology, crystalline and the formation of the
nanostructures were investigated. We found that the morphology and crystalline phase strongly depended on the hydrochloric
acid concentrations. More importantly, crystalline phase was closely related to the morphology of TiO2 nanostructure. Nanoparticles were polycrystalline anatase phase, and aligned nanorods were single crystalline rutile phase.
Possible formation mechanisms of TiO2 nanostructures with various crystalline phases and morphologies were proposed. 相似文献
992.
The effects of liquid velocity, nozzle diameter, gas chamber volume and gas flow rate on volumes, shapes and growth curves of bubbles formed at a nozzle submerged in a cocurrently upward flowing liquid in a bubble column were experimentally investigated. The bubble volume decreases with increasing liquid flow velocity. The effect of liquid flow velocity on the volume of bubble increases with an increase in the gas flow rate. To simulate bubble formation at a nozzle submerged in cocurrently upward flowing liquid, a revised non-spherical bubble formation model was proposed. Bubble volumes, bubble growth curves and shapes experimentally obtained in this study, as well as in previous experimental studies, are well predicted by the present model. 相似文献
993.
Gilson Hideki Nabechima João Gustavo Provesi Márcia Barbosa Henriquez Mantelli Manoela Alano Vieira Renata Dias De Mello Castanho Amboni Edna Regina Amante 《Journal of food science》2014,79(2):C163-C168
The green coloring is the first characteristic in mate tea (chimarrão). Mate producers perform the sapeco process by rapidly passing the leaves through flames. It has been proven that this procedure leads to high energy consumption and also to excessive exposure of the raw material to heat. In this present work, the effect of sapeco on the inactivation of peroxidase, the color, and degradation of the chlorophyll in mate was evaluated by performing the sapeco procedure in a conveyor oven, without any direct contact with the flames. The mate processed in a conveyor oven was compared with mate processed in mate factories. Inactivation of peroxidase showed that sapeco performed in a conveyor oven at 255 ºC for 20 s can replace the traditional process of the industrial sapeco. This time/temperature binomial is significantly important for the green coloring and the minimization of chlorophyll degradation, besides representing a significant reduction in the temperature traditionally applied in the industrial sapeco of mate. 相似文献
994.
Fang Fang Yang Mu Guo-Ping Sheng Han-Qing Yu Yu-You Li Kengo Kubota Hideki Harada 《International Journal of Hydrogen Energy》2013
Anaerobic hydrogen production by mixed cultures is a complex process, and information about its kinetic analysis is sparse. In this study, an integrated approach with the weighted nonlinear least-squares analysis and accelerating genetic algorithm is proposed to evaluate the kinetic parameters of biohydrogen production from a sucrose by mixed anaerobic cultures. The weighted nonlinear least-squares analysis is used to calculate the differences in gaseous and aqueous product concentrations between the predicted and the measured results, while the accelerating genetic algorithm is utilized to optimize the objective function by minimizing the total sum of the squared weighted errors. The kinetic parameters for specific maximum substrate uptake rate, substrate uptake affinity constant, yield coefficient are calculated with this approach, and are validated by the results of the independent experimental results reported in literature. This integrated approach is effective and rapid to estimate the anaerobic hydrogen production kinetics by mixed cultures. 相似文献
995.
Computational Visual Media - Although many photorealistic relighting methods provide a way to change the illumination of objects in a digital photograph, it is currently difficult to relight... 相似文献
996.
Hideyuki Morimoto Hideki Yamashita Masahiro Tatsumisago Tsutomu Minami 《Journal of the American Ceramic Society》1999,82(5):1352-1354
New amorphous materials were mechanochemically synthesized by use of crystalline starting materials of Li2 S and SiS2 . The conductivity of a mechanochemically prepared sample of 60Li2 S40SiS2 (mol%) after a milling for 20 h was around 10-4 Scm-1 at room temperature. This conductivity was comparable to that of the corresponding glassy powders prepared by twin-roller rapid quenching of melt and then pulverizing. The transport number of lithium ions in the mechanochemically prepared sample was nearly unity. Mechanochemical synthesis is a promising way to produce new solid electrolytes for solid-state lithium secondary batteries. 相似文献
997.
Toshihiko Hoshide Motoki Tanaka Hideki Tsujiai 《Journal of Materials Engineering and Performance》2013,22(4):1079-1084
The long-term durability of ceramics coated glass with high performance should be appropriately evaluated prior to their applications. Fatigue properties of such materials should be clarified to ensure the long-term durability. In this work, a borosilicate glass was coated with single- and two-layered ceramic thin films by a sputtering method. Fatigue tests of coated glass were conducted under bending mode, and fatigue properties of coated glass were investigated. It was revealed that the fatigue life of glass coated with two-layered film became longer compared with those of glass substrate and glass coated single-layered film. Hardness as surface characteristics of coated films, and bending strength as bulk property of coated glass were correlated with the average fatigue life, though no good correlation was found between them. Fatigue resistance strength was proposed as another strength parameter. It was found that the average fatigue life was adequately expressed by a power function of fatigue resistance strength. 相似文献
998.
Xiangqing Pan Hiroyuki Kaneko Hideki Ushio Toshiaki Ohshima 《European Journal of Lipid Science and Technology》2005,107(4):228-238
The isomeric hydroperoxide distribution and the composition of volatiles generated by oxidation of all‐cis‐7,10,13,16,19‐docosapentaenoic acid ethyl ester (DPA Et) were determined. DPA Et was prepared by using seal blubber oils as raw material and purified by urea complexation and reverse‐phase high‐performance liquid chromatography (HPLC). The DPA Et of over 96% purity thus obtained was dissolved in methanol and subsequently divided into two portions. One portion was added with methylene blue and exposed to a tungsten bulb light at 5 °C for photosensitized oxidation. The other portion was added with 2,2'‐azobis (2,4‐dimethylvaleronitrile) as an azo‐radical initiator and kept in the dark at room temperature for autoxidation. Positional isomers of hydroperoxides generated by autoxidation or photosensitized oxidation of DPA Et were separated by normal‐phase HPLC and detected by a fluorescence detection system as well as UV absorption. The peak components were identified by gas chromatography‐mass spectrometry (GC‐MS). Eight isomeric hydroperoxides, including certain amounts of 7‐, 10‐, 11‐, 13‐, 14‐, 16‐, 17‐, and 20‐hydroperoxy docosapentaenoate, were generated by autoxidation of DPA Et. The photosensitized oxidation of DPA Et yielded not only the above eight hydroperoxide isomers but also two additional isomeric hydroperoxides, 8‐ and 19‐hydroperoxy docosapentaenoate, which are characteristic hydroperoxide isomers generated by singlet oxygen‐mediated oxidation. Volatiles formed by autoxidation of DPA Et at 50 °C were collected and analyzed by solid‐phase micro‐extraction and GC/GC‐MS. A number of aldehydes, ketones, alcohols, acids, furans and hydrocarbons were identified. The formation mechanisms of certain volatiles are discussed. 相似文献
999.
Tadaaki Shimizu Mirko PeglowKazuaki Yamagiwa Masato TanakaShinichi Sakuno Nobuhiro MisawaNobuyuki Suzuki Hachiro UedaHiroshi Sasatsu Hideki Gotou 《Chemical engineering science》2002,57(19):4117-4128
A mathematical model of SO2 capture by uncalcined limestone particles with solid attrition under pressurized fluidized bed combustion conditions was developed based on the shrinking unreacted-core model. Since the thickness of the product layer is sufficiently much smaller than the particle size, a flat surface model was employed. The difference in SO2 capture behavior between continuous solid attrition and intermittent attrition was investigated. The reaction rate for intermittent solid attrition was found to be lower than that for continuous attrition mode under low SO2 concentration conditions. A simple mathematical expression to calculate reaction rate of SO2 capture per unit external surface area of limestone is proposed.The present simplified mathematical model of SO2 capture by single limestone particle under periodical attrition conditions was applied to the analysis of a large-scale pressurized fluidized bed combustor. By giving the period of attrition as a parameter, the experimental results agreed well with the model results. From the vertical concentration profile of SO2 concentration, the emission of SO2 was found to be governed by the balance between SO2 formation rate from char and SO2 capture by limestone at the upper surface of the dense bed. A simplified expression to estimate SO2 emission from pressurized fluidized bed combustors was proposed. 相似文献
1000.
Mitsuo Miyazawa Hideki Kawazoe Mitsuro Hyakumachi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2002,77(1):21-24
The biotransformation of l‐menthol was investigated by using nine isolates of Rhizoctonia solani (AG‐1‐IA Rs24, Joichi‐2, RRG97‐1; AG‐1‐IB TR22, R147, 110.4; AG‐1‐IC F‐1, F‐4 and P‐1) as a biocatalyst. In the cases of Rhizoctonia solani F‐1, F‐4 and P‐1, almost all of the substrate was consumed in 3 days and the major metabolite increased rapidly for the first of 3 days incubation. The structure of the major metabolite was elucidated on the basis of its spectral data. The major metabolite was determined to be (?)‐(1S,3R,4S,6S)‐6‐hydroxymenthol which indicated that l‐menthol was hydroxylated at the C‐6 position. From the main component analysis, the nine isolates of Rhizoctonia solani were divided into two groups based on their ability to transform l‐menthol to (?)‐(1S,3R,4S,6S)‐6‐hydroxymenthol. This is the first report on the biotransformation of l‐menthol by Rhizoctonia solani. © 2001 Society of Chemical Industry 相似文献