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1.
The bistable field effect transistor (BISFET) is a novel inversion-channel switching device exhibiting abrupt current transitions and hysteresis in its output characteristics. The semiconductor structure of the BISFET is compatible with a range of electronic and optoelectronic devices. In this work, integration of a BISFET with an LED is reported. Both devices have been implemented on a single semiconductor substrate using a single fabrication sequence. The BISFET is used to current drive the LED. Abrupt transitions and hysteresis are seen in the optical output from the circuit in the range of gate voltage from 1.75 V to 1.9 V 相似文献
2.
P. D. Srivastava Sarita Ojha 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2014,18(5):1027-1032
In this paper, we introduce the concept of $\lambda $ -statistical convergence of order $\theta $ and strong $\lambda $ -summability of order $\theta $ for the sequence of fuzzy numbers. Further the same concept is extended to the sequence of fuzzy functions and introduce the spaces like $S_\lambda ^\theta (\hat{f})$ and $\omega _{\lambda p} ^\theta (\hat{f})$ . Some inclusion relations in those spaces and also the underlying relation between these two spaces are also obtained. 相似文献
3.
The electrical conductivity, σ, and thermoelectric power, S, of copper chromite (CuCr2O4) are reported in the temperature range 295 to 815 K. A break (T B) in the slope of the plot of log σ against T ?1 was observed around 556 K. Apart from this break, the curves are linear, and their slopes correspond to activation energies of 0.60 eV (T B<556 K) and 1.22 eV (T B>556 K). A break (T′ B) in the slope of the -S against T ?1 plot was also observed round 556 K. Apart from the break at this temperature, the S against T ?1 curves are linear. At T′ B>556, S can be expressed by the relation $$S = - \left[ {\left( {\frac{{0.65 eV}}{{{\text{2}}eT}}} \right) + (0.42) mV K^{ - {\text{1}}} } \right]$$ The mechanism involved in the electrical transport is the hopping of holes from Cr4+ centres to neighbouring Cr3+ ions. The typical hopping mobility of the holes is of the order of 106 m2 V?1 sec?1. The mobility activation energy of the holes in CuCr2O4 decreases with temperature due to the smoothing of the potential barriers between Cr4+ and Cr3+ sites. 相似文献
4.
Different coloured thallous tungstates were prepared by solid state reaction between thallous carbonate and tungsten trioxide at higher temperatures. The structure and thermal stability of different thallous tungstates were determined by powder X-ray diffraction and thermogravimetric analysis, respectively. The electrical conductivity () and thermoelectric power (5) of pressed solid pellets of Tl2WO4 are reported in the temperature range 295 to 950 K. It is concluded that these materials have large numbers of oxygen ion vacancies and conduction occurs due to the electrons left by oxygen ions while escaping the solid. These electrons are trapped in the valence band and form centres analogous to a helium atom and electrical conductivity results when they enter the conduction band. The values of donor ionization energies have also been evaluated. 相似文献
5.
6.
A novel technique was used to fabricate nickel flow models of a straight pipe and a Y‐bifurcation. These were used to obtain integral mass transfer coefficients by the electrochemical technique. For the straight pipe, good agreement was obtained with previously reported mass transfer correlations. The use of an upstream anode in addition to the downstream anode led to higher mass transfer at the cathode with laminar flow because of the additional near‐wall ions produced by the upstream anode. With increasing Schmidt number, the effect of transition from laminar to turbulent flow on mass transfer was delayed to progressively higher Reynolds numbers because of the reduced mass transfer boundary layer thickness relative to the viscous sublayer. With the Y‐bifurcation, possible flow separation and the formation of a new mass transfer boundary layer in the daughter branches significantly influence the mass transfer behaviour. 相似文献
7.
Anupam Ojha Barun Das Shyamal Kumar Mondal Manoranjan Maiti 《Applied Soft Computing》2013,13(8):3703-3712
This paper presents the recently introduced modified subgradient method for optimization and its effectiveness in a fuzzy transportation model. Here a multi-item balanced transportation problem (MIBTP) is formulated where unit transportation costs are imprecise. Also available spaces and budgets at destinations are limited but imprecise. The objective is to find a shipment schedule for the items that minimizes the total cost subjected to imprecise warehouse and budget constraints at destinations. The proposed model is reduced to a multi-objective optimization problem using tolerances, then to a crisp single-objective one using fuzzy non-linear programming (FNLP) technique and Zimmermann's method. The above fuzzy MIBTP is also reduced to another form of deterministic one using modified sub-gradient method (MSM). These two crisp optimization problems are solved by Genetic Algorithm (GA). As an extension, fuzzy multi-item balanced solid transportation problems (STPs) with and without restrictions on some routes and items are formulated and reduced to deterministic ones following FNLP and Zimmermann's methods. These models are also solved by GA. Models are illustrated numerically, optimum results of fuzzy MIBTP from two deductions are compared. Results are also presented for different GA parameters. 相似文献
8.
Yi-Ming Zhao Shikha Ojha Catherine M. Burgess Da-Wen Sun Brijesh K. Tiwari 《International Journal of Food Science & Technology》2021,56(2):721-732
This study aimed to evaluate the influence of plasma treatment time, bacterial exposure time to PAW and bacterial species on the inactivation efficacy of plasma-activated water (PAW), with additional investigation of the inactivation mechanisms of PAW. Six bacterial species, including Listeria innocua, Staphyloccus aureus, Escherichia coli, Pseudomonas fluorescens, Shewanella putrefaciens and Aeromonas hydrophila were selected as the representative bacteria. The initial bacterial concentration was around 7 log CFU ml−1 after mixing with PAW, and the inactivation efficacy was measured after different exposure times during the 4 °C storage. Scanning electron microscopy (SEM) images of the bacteria after PAW treatment were carried out to inspect the cell structure damage, and physicochemical properties of PAW, including pH, conductivity and long-living reactive species of H2O2, , and , were examined. The results showed that the inactivation efficacy of PAW was positively correlated with plasma treatment time and bacterial exposure time, and for the species examined in this study, the Gram-negative species were more sensitive to PAW than the Gram-positive species. Cell structure damage, including shrinkage, distortion, or holes, was observed after PAW treatment. The pH of PAW was acidified to 2.5–2.9, and conductivity was significantly increased to 518.0 μs cm−1. and H2O2 were reduced during the 48 h storage, while an increased concentration was observed for . This study demonstrated that the processing parameters of plasma treatment time, exposure time and characteristics of bacteria can significantly affect the inactivation efficacy of PAW. 相似文献
9.
Abstract Surfactant-based fracturing gels are considered as clean gels due to the absence of insoluble residues after hydraulic fracturing of tight reservoir. Conventionally used highly viscous polymer gels damage the formation by blocking the fluid path in a fractured formation. The present work has been accomplished with the purpose of evaluating an anionic surfactant-based gel for hydraulic fracturing. Rheological properties and proppant carrying capacity of the synthesized gel were studied as a function of shear rate, temperature, and pH, which affect the gel behavior at the downhole. Proppant carrying capacity was also reported with varying proppant loadings. Rheological properties and proppant carrying capacity of synthesized gel were compared with conventionally used guar gel. 相似文献
10.