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131.
Yong-Hong Ye Y.J. HuangW.T. Lu B.D.F. CasseD. Xiao S.P. BennettD. Heiman L. MenonS. Sridhar 《Optical Materials》2011,33(11):1667-1670
We fabricated a series of gold nanowires/alumina composite films with different wire lengths. Optical transmission measurements confirmed that the composite films exhibit transverse and longitudinal surface plasmon resonances. We show that the wavelength of the longitudinal resonance is sensitive to nanowire length, while that of the transverse resonance is not. The experimental results are in agreement with the modeled results based on the Maxwell Garnett effective medium theory. Moreover, the window for negative refraction of the samples can be tuned in synchronism with the longitudinal resonance by the nanowire length. 相似文献
132.
A non-linear form relating vegetation indices (VI) to crop grain yields which normalizes for differences in acquisition date is suggested. It is based on the assumption that deviations in VI near the peak VI follow a quadratic behaviour. This form gave a higher R2 value than a simple VI-yield linear model on a multi-year, multi-location data set of IRS (Indian Remote Sensing Satellite-1A) LISS-I(Linear Imaging Self Scanner-I) derived near-infrared (NIR)/red radiance ratios and wheat grain yields in a study site in Madhya Pradesh (India). As the suggested model includes time of peak as a variable, it allows integration of results from other sources, such as, weather-based crop phenology model or high repetivity spectral data into the VI-yield relation. 相似文献
133.
Ronald G. Harvey Qing Dai Chongzhao Ran Sridhar R. Gopishetty Trevor M. Penning 《Polycyclic Aromatic Compounds》2013,33(4-5):257-269
Three mechanisms have been proposed to explain the carcinogenic activities of polycyclic aromatic hydrocarbons (PAHs). On the basis of the nature of the active metabolites involved, they may be termed: the diol epoxide mechanism, the quinone mechanism, and the radical-cation mechanism. In connection with studies to evaluate the relative importance of these pathways, we required practical methods for the syntheses of the active PAH metabolites involved. We now report efficient new synthesis of the o-quinones of benzo[a]pyrene (BPQ), 7,12-dimethylbenz[a]anthracene (DMBAQ), and benz[a]anthracene (BAQ). These quinones are convenient synthetic precursors of the related o-catechols, trans-dihydrodiols, and diol epoxides, as well as the stable adducts of the o-quinones with 2-deoxyadenosine and 2′-deoxyguanosine. 相似文献
134.
135.
This communication is based on exergy concept for the utilization of solar thermal energy in a Rankine cycle‐based fuel‐fired thermal power plant (FFTPP). It has been shown that solar thermal energy as an aided source for feed water preheating helps to reduce the exergy loss in feed water heater (FWH) of Rankine cycle and develops more work than that could have been produced in a solar thermal power plant (STPP). It has been found that this enhancement in work increases for low‐pressure FWHs. For further illustration, a case study has been carried out of a typical 50 kW STPP and a 220 MW FFTPP. The effect of utilizing the same input solar thermal energy of typical STPP, if used as an aided source in a 220 MW FFTPP for feed water preheating is investigated. The work output of STPP is 59.312 kW, while the extra work output of FFTPP by using solar thermal energy of STPP is 90.27 kW. It has been found that the efficiency of work conversion of aided solar thermal energy in FFTPP is higher than the efficiency of work conversion in STPP. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
136.
Takayuki Tsukada Sridhar Venigalla James H. Adair 《Journal of the American Ceramic Society》1997,80(12):3187-3192
The feasibility of synthesizing crystalline ZrO2 films at low temperatures was evaluated using an electrochemical method. Anodization of zirconium-metal substrates in tetraethyl ammonium hydroxide (TEAOH) solutions under constant applied voltage conditions at ∼25° and ∼100°C was investigated. The chemistry and microstructure of the anodic oxide films deposited on the zirconium-metal substrates under the above conditions were characterized using X-ray diffractometry and scanning electron microscopy. The results indicated that, with sufficiently high applied voltages (in the range of 300 V) at pH ∼9.5, the initial dissolution of the zirconium anode resulted in the local saturation of the electrolyte solution with Zr4+ , forming Zr(OH)− 5 , which deposited electrophoretically on the anode as a thick, gelatinous film at 25°C. Similar treatments at 100°C resulted in an in situ crystallization of Zr(OH)4 gel to monoclinic ZrO2 . 相似文献
137.
M. P. Sridhar Kumar B. Viswanathan C. S. Swamy V. Srinivasan 《Journal of Materials Science》1986,21(7):2335-2338
X-ray photoelectron spectroscopic studies on the activated pure CaNi5 alloy as well as the hydride formed at 1 atm pressure and room temperature, CaNi5H4.8, showed that on activation calcium segregates to the surface and forms the oxide, whereas most of the nickel on the surface is present in the metallic form. This indicates that the coexistance of the oxide phase and the metal phase is essential for the facile hydriding behaviour of CaNi5. 相似文献
138.
A relationship between copper in slag and copper in matte during copper sulfide smelting has been derived using industrial
data from 42 plants employing blast furnaces, reverberatory furnaces, flash furnaces, and Mitsubishi smelting furnaces together
with the available thermodynamic equilibrium data for Cu-Fe-S-O, FeO-SiO2, and Cu-Fe-S systems and laboratory slag-matte equilibrium information. A copper smelting diagram showing oxygen potential;
sulfur potential; and copper, magnetite, and sulfur contents in slag during the smelting of different grades of copper mattes
is developed for mattes containing less than 70 pct copper. The data presented can be used to determine the entrained copper
losses in slag. Further, by combining the calculated value of the entrained matte with the corresponding plant data for the
sulfur content of the slag, it is possible to derive the dissolved sulfur content of the slag. These calculated values were
in excellent agreement with the experimentally determined sulfide capacity of fayalite slags. It is shown that there is no
need to assume the presence of dissolved copper sulfide species in industrial slags. The existing equilibrium data that relate
the copper content of slags to oxygen potential adequately describe the copper losses in industrial slags. 相似文献
139.
140.
W. Deweerd V. Kaushik J. Chen Y. Shimamoto T. Schram L.-. Ragnarsson A. Delabie L. Pantisano B. Eyckens J.W. Maes S. De Gendt M. Heyns 《Microelectronics Reliability》2005,45(5-6):786
In this paper, we report on several different approaches that were implemented on both capacitor and scaled planar MOS transistor devices in order to prevent or undo the commonly observed VT/Vfb-shift and –instability for Hf-based high-κ gate stacks in conjunction with a poly-Si electrode. While the latter issue can eventually be mitigated, the VT-shift problem jeopardizes initial high-κ integration with poly-Si for the 65 nm and also for the 45 nm node. The different attempts to circumvent this problem include (1) bulk modifications of the high-κ stack/process, (2) the use of various thin capping layers at the poly/high-κ interface and (3) chemical and process modifications of the gate electrode deposition. We have observed that, although considerable improvements have been made in terms of e.g. yield, performance and instability, none of these techniques succeeded in obtaining VT-values in line with the ITRS device specifications, i.e. avoiding Fermi Level Pinning to occur for poly-Si/Hf(Si)O(N) stacks. 相似文献