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991.
The incorporation of [1-14C]linoleic acid (LA) into lipids ofMortierella ramanniana var.angulispora was studied to determine which lipid classes participated in the δ6-desaturation of [1-14C]LA. [1-14C]LA was rapidly taken up into fungal cells and esterified into various lipids. Comparison of the profile of [1-14C]LA incorporation between fungal cells at the exponential growth phase and the stationary growth phase showed that [1-14C]LA incorporation into most lipids—except for triacylglycerol (TG) and phosphatidylcholine (PC)—were greatly reduced at the
stationary growth phase. Desaturation of [1-14C]LA into λ-linolenic acid (GLA) readily occurred at the exponential growth phase, but was greatly decreased at the stationary
growth phase. Moreover, pulse-chase experiments revealed that the radiolabel incorporated into phosphatidylserine (PS) and
PC rapidly turned over, while that in TG and diacylglycerol (DG) accumulated after the 4 hr chase. In addition to the change
of the radiolabel in individual lipids, the content of radiolabeled GLA converted from [1-14C]LA varied with individual lipids. In phospholipids such as PC, phosphatidylethanolamine (PE) and PS, radiolabeled GLA rapidly
increased after 1 hr and then decreased after 4 hr. On the other hand, a gradual increase in radiolabeled GLA until 4 hr was
observed in TG. These results suggest that LA, which has been esterified into phospholipids such as PC, PE and PS, is readily
desaturated to GLA, which is then transferred to TG. These differences in the fate of GLA derived from LA between phospholipids
and neutral lipids may be reflected in the GLA content in the individual lipids. 相似文献
992.
Yoshihisa Watanabe Osamu Yamada Katsuhisa Fujita Yoshinobu Takegami Toshimitsu Suzuki 《Fuel》1984,63(6):752-755
Hydroliquefaction of Japanese Miike and Taiheiyo coals was carried out using various iron complexes as catalysts in tetralin at 375–445 °C. Iron pentacarbonyl (Fe(CO)5) showed the highest catalytic activity, increasing coal conversion by about 10% at 425 °C under an initial hydrogen pressure of 5 MPa. Amounts of hydrogen transferred to coal increased from 1.4–2.3 wt% of daf coal in the absence of the catalyst to 2.5–4.2 wt% of daf coal in the presence of Fe(CO)5 at 425 °C. 相似文献
993.
Baolu Shi Bo Li Xiaoyao Zhao Run Chen Osamu Fujita Ningfei Wang 《International Journal of Hydrogen Energy》2018,43(31):14806-14815
In this study hydrogen flames have been attempted in a rapidly mixed tubular flame combustor for the first time, in which fuel and oxidizer are individually and tangentially injected into a cylindrical combustor to avoid flame flash back. Three different cases were designed to examine the effects of fuel and oxidizer feeding method, diluent property, oxygen content and equivalence ratio on the characteristics of hydrogen flame, including the flame structure, lean extinction limit, flame stability and temperature. The results show that by enhancing mixing rate through feeding system, the range of equivalence ratio for steady tubular flame can be much expanded for the N2 diluted mixture, however, at the oxygen content of 0.21 (hydrogen/air) the steady tubular flame is achieved only up to equivalence ratio of 0.5; by decreasing oxygen content, the lean extinction limit slightly increases, and the upper limit for steady tubular flame establishment increases significantly, resulting in an expanded tubular flame range. For CO2 diluted mixture, the stoichiometric combustion has been achieved within oxygen content of 0.1 and 0.25, for which the burned gas temperature is uniformly distributed inside the flame front; as oxygen content is below 0.21, a steady tubular flame can be obtained from the lean to rich limits; and the lean extinction limit increases from 0.17 to 0.4 as oxygen content decreases from 0.21 to 0.1, resulting in a shrunk tubular flame range. Laminar burning velocity, temperature and Damköhler number are calculated to examine the differences between N2 and CO2 diluted combustion as well as the requirement for hydrogen-fueled tubular flame establishment. 相似文献
994.
Effect of sesamin on mitochondrial and peroxisomal β-oxidation of arachidonic and eicosapentaenoic acids in rat liver 总被引:1,自引:0,他引:1
The effects of dietary sesamin on the hepatic metabolism of arachidonic (AA) and eicosapentaenoic (EPA) acids, were investigated
with respect to their β-oxidation and secretion as triacylglycerol (TG). For 2 wk, rats were fed three types of dietary oils:
(i) corn oil (control) group; (ii) FPA group: FPA ethyl esters/rapeseed oil=2∶3; (iii) AA group: AA ethyl esters/palm oil/perilla
oil=2∶2∶1, with or without 0.5% (w/w) of sesamin. Dietary sesamin significantly increased the activities of hepatic mitochondrial
and peroxisomal fatty acid oxidation enzymes (mitochondrial carnitine acyltransferase I, acyl-CoA dehydrogenase, and peroxisomal
acyl-CoA oxidase). Dietary FPA increased mitochondrial carnitine acyltransferase I and peroxisomal acyl-CoA oxidase. Dietary
AA, however, had an effect on peroxisomal acyl-CoA oxidase only. In whole liver and the TG fraction, EPA and AA concentrations
were significantly increased by dietary EPA and AA, respectively, and were decreased by dietary sesamin. In hepatic mitochondria
and peroxisomes, EPA concentration was increased by dietary EPA, but AA was not changed by dietary AA. The addition of dietary
sesamin to the EPA-supplemented diet significantly decreased the EPA concentration compared to concentrations found with consumption
of dietary EPA alone. These results suggest that sesamin increased β-oxidation enzyme activities and reduced hepatic EPA and
AA concentrations by degradation. The stimulating effect of sesamin on β-oxidation, however, was more significant in the EPA
group than in the AA group. Hepatic AA concentration was altered by the joint effect of sesamin through esterification into
TG and the stimulation of β-oxidation. 相似文献
995.
Toyoji Kakuchi Osamu Haba Yasuhiro Harada Hisaho Hashimoto Kazuaki Yokota 《Polymer Bulletin》1992,27(6):599-605
Summary Cyclopolymerization of 2,6-bis[3-(4,5-epoxy-2-oxapentyl)-2-methoxy-5-methylphenyl]-4-methylanisole was carried out with cationic, anionic, and coordination catalysts. The polymers obtained with BF3·OEt2 or SnCl4 in dichloromethane and with t-BuOK in DMSO were soluble in benzene, chloroform, and THF. The mole fractions of the cyclic units in these polymers were from 0.65 to 0.75. The resulting poly(hemispherand) bound alkali metal cations and the selectivity was in the order of Rb+>K+>Cs+>Na+>Li+. 相似文献
996.
Molecular orientation of polycarbonate (PC) in injection‐molded parts with microscale features was characterized by means of polarized Raman spectroscopy, and the relationship between microstructure and replication was discussed. The microscale feature size of continuous v‐groove was 20 μm in depth and 50 μm in width. PC injection‐molded parts were molded with various molding conditions. The molecular orientation distribution along flow direction on the cross‐section of molding parts were evaluated by the intensity ratio of the bands at 635 to 703 cm?1 (I635/I703) in the Raman spectra. Molecular orientation along the flow direction inside the v‐groove was higher than that of the core and the opposite surface region. In particular, the highest molecular orientation was at the surface of the v‐groove. Among the injection molding conditions, the mold temperature showed significant effect on the molecular orientation and replication. Higher mold temperature caused high replication and low molecular orientation. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
997.
The elongational viscosity of polypropylene has been investigated by isothermal melt spinning, carried out over a range of experimental conditions. The filament diameter and the elongational force were measured for running filaments and the relationship between elongational viscosity and elongational strain rate reported. The elongational viscosity was observed to decrease in the vicinity of the spinneret and then remained constant before increasing along the thread line. An increase in elongational viscosity did not occur within the isothermal zone until the elongational flow was fully developed. The onset of an increase in elongational viscosity was determined from the constant total elongational strain. The degree of molecular orientation was also studied by birefringence measurements and was investigated as a function of elongational stress. At a high elongational stress, the relation between birefringence and elongational stress departed from linearity and exhibited a rapid increase which can be related to the increase in elongational viscosity. 相似文献
998.
The diameters of C60 nanowhiskers (C60NWs), which are prepared by a simple liquid–liquid interfacial precipitation method, can be tuned appropriately by controlling the area size of liquid–liquid interface. The diameters of C60NWs decrease with decreasing the area size of liquid–liquid interface. The electronic spectra of C60NWs show a dependence on the diameters of C60NWs, reflecting strength of interaction among the C60 molecules in each C60NW. 相似文献
999.
Shuichi Sakuma Shiro Yamauchi Osamu Takai 《Journal of Applied Electrochemistry》2010,40(12):2153-2160
A two-layer model for a solid polymer electrolytic (SPE) dehumidifier is applied to a system in which the chamber to be dehumidified
has some leakage area. By introducing this area, the attainable humidity in the chamber, which is the steady-state humidity
to be attained after a long-time dehumidification, can be defined. Experimental results of dehumidification by an SPE dehumidifier
are compared to the calculations based on the two-layer model for the SPE dehumidifier, which was presented in our previous
paper. Equations for the two-layer model are simplified by making use of assumptions for the current characteristics and a
constant environmental condition, and it is reduced to equations including a differential equation on the time variation of
the humidity in the chamber. The differential equation to describe the attainable humidity in the chamber and time constant
for the dehumidification is obtained. The current flowing in the dehumidifier under steady state conditions is also given
as a function of the humidities in the spaces facing the anode and the cathode. A diagram to estimate the attainable humidity
and the time required for dehumidification from the dehumidifying area and leakage area is also given. 相似文献
1000.
In the ITER edge Thomson scattering measurement system, polychromators with optical band-pass filters and avalanche photodiodes are planned to be used. In this paper, we optimized the transmission wavelength ranges of the optical filters by a numerical method. Since measurements in a high electron temperature range are required for the measurement system, the Thomson spectrum could overlap a strong line emission of Dα when the electron temperature is rather high. It is shown that a filter whose transmission wavelength range is shorter than Dα becomes important to decrease the measurement error in the high temperature range. Moreover, it is found that a filter whose transmission wavelength range is above 1064 nm (laser wavelength) is useful to improve the measurement accuracy, in particular, when the number of filters is more than six. 相似文献