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91.
Bharti K. Iyer 《LWT》2008,41(6):1053-1059
Idli is a fermented breakfast food widely consumed in Southern India. It is liked by people mainly due to its sensory attributes such as mouthfeel, appearance, taste and aroma. Fermentation time of the batter varies from 14 to 24 h with overnight fermentation being the most frequent time interval. Reduction in the fermentation time of the idli batter is of great commercial significance for large-scale idli production and this can be potentially achieved by addition of enzymes externally. The present study was undertaken to explore the possibility of expediting the idli batter fermentation process by adding an exogenous source of α-amylase enzyme. 5, 15 and 25 U per 100 g batter of amylase were added to the idli batter which was allowed to ferment. Different parameters were monitored and sensory attributes were also studied and compared with that of the control set. The fermentation time was reduced from a conventional 14 h to 8 h and the sensory attributes of the final product were also successfully maintained. 相似文献
92.
Poly(phenylene oxide)s were synthesized by the oxidative polymerization of 2‐phenyl phenol (PP) and 2‐allyl phenol (AP). The copolymers were also synthesized with 80 mol % PP and 20 mol % AP and with equimolar monomers. The polymers were characterized. Blends of these polymers with poly(vinylidene fluoride) were prepared. These blend membranes were sulfonated, and their suitability for applications in fuel cells was evaluated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 307–311, 2003 相似文献
93.
This paper aims to open a new line of research by demonstrating the feasibility of monitoring breathing function in a highly automated and noncontact fashion. The method is based on the statistical modeling of dynamic thermal data captured through a highly sensitive infrared imaging system. This method achieved an accuracy of 96.43% on a small set of subjects during rest and after brief exercise. It has the potential to provide a unique capability for sustained monitoring of chronic or acute breathing problems and in sleep studies by overcoming the deficiencies of the existing measurement modalities. The method also opens the way for the next generation contact-free polygraphy that will not affect the subject's psychophysiology. 相似文献
94.
The rate of formation of intermetallic compounds between aluminum and three ferritic steels, one austenitic steel, and Inconel
has been determined by an electrolytic method. The steel was held at zero potential with respect to aluminum in a NaCl-AlCl3 melt, and the current measured. Comparison of measured thicknesses of intermetallic layers with those calculated from the
integrated current gives an average deposition efficiency of 95 pct. For the Type 304 austenitic steel thickness
(min), andk is given by logk= −6400/T(0K) +4.469. The ferritic steels show a linear rate of growth of Al5Fe2, with an initial higher rate such that extrapolation of the linear curve back to zero time gives an intercept of 16±7 μm.
The rate constants (mm min−1) may be represented by log (rate)=α/T+β, and the values of α and β are respectively −2650 and−0.788 for a plain carbon steel,−6580 and + 3.469 for a 1.3 pct Cr,
0.4 pct Mo steel, and−5950 and +2.466 for a 2.2 pct Cr, 0.9 pct Mo steel. The more highly alloyed steels are thus attacked,
more slowly. Results for Inconel could not be fitted to any simple equation. With the ferritic steels growth is by aluminum
diffusing inwards; with Inconel it is by nickel diffusing outward. 相似文献
95.
96.
It has been found that stabilization of austenite by hydrogen is governed not by its amount but by the manner of its introduction into the austenite just prior to transformation into martensite. In this case stabilization is to be understood as a decreasing tendency to transformation into martensite. The experimental results obtained using an appropriate material (steel No. 1.4576) show that cathodic impregnation brings about a stabilization of austenite as defined above. 相似文献
97.
N. Subramanyan K. Ramakrishnaiah S. Venkatakrishna Iyer V. Kapali 《Corrosion Science》1978,18(12):1083-1089
The corrosion and polarization of steel have been investigated in 1N sulphuric acid, containing n-dibutyl sulphide labelled with radioactive sulphur atom. In addition, the electrocapillary behaviour of the radioactive substance on a mercury surface in the acid has been tested. Similar experiments employing non-radioactive dibutyl sulphide (d.b.s.) and hydrogen peroxide have been carried out.The inhibition of corrosion of steel in IN sulphuric acid by d.b.s. is significantly reduced and under some conditions corrosion is accelerated by the radioactive form. The polarization and the electrocapillary behaviour of radioactive d.b.s. solutions are clearly different from that of the non-radioactive compound. There is some similarity in the effects produced by radioactive d.b.s. and by a combination of non-radioactive d.b.s. and hydrogen peroxide, in respect of corrosion inhibition and electrocapillary behaviour. It is concluded that the effects produced by radioactive d.b.s. can be attributed mainly to the hydrogen peroxide produced by radiolysis, though the radioactivity can also affect the electrical characteristics at the metal-solution interface. 相似文献
98.
Patton G.L. Iyer S.S. Delage S.L. Tiwari S. Stork J.M.C. 《Electron Device Letters, IEEE》1988,9(4):165-167
The devices were fabricated using molecular-beam epitaxy (MBE), low-temperature processing, and germanium concentrations of 0, 6%, and 12%. The transistors demonstrate current gain, and show the expected increase in collector current as a result of reduced bandgap due to Ge incorporation in the base. For a 1000-Å base device containing 12% Ge, a six-times increase in collector current was measured at room temperature, while a 1000-times increase was observed to 90 K. The temperature dependence of the collector current of the Si0.88Ge0.12 base transistor is consistent with a bandgap shrinkage in the base of 50 meV. For the homojunction transistors, base widths as thin as 800 Å were grown, corresponding to a neutral base width of no more than 400 Å 相似文献
99.
100.
The limiting noise mechanism in field effect transistors is thermal noise of the conducting channel. An analysis of the thermal noise in a linearly tapered inhomogeneous channel FET is presented leading to a solution for the open circuit noise voltage and the short circuit noise current. Improvement in the open circuit noise voltage for the inhomogeneous FET is shown directly from a comparison with the solution for a homogeneous channel FET. 相似文献