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991.
In this paper, we have developed a new full-adder cell using multiplexing control input techniques (MCIT) for the sum operation and the Shannon-based technique to implement the carry. The proposed adder cell is applied to the design of several 8-bit array multipliers, namely a Braun array multiplier, a CSA multiplier, and Baugh–Wooley multipliers. The multiplier circuits are designed using DSCH2 VLSI CAD tools and their layouts are generated by Microwind 3 VLSI CAD tools. The output parameters such as propagation delay, total chip area, and power dissipation are calculated from the simulated results. We have also calculated energy per instruction (EPI), throughput, latency, signal-to-noise ratio (SNR), and the effect of temperature on the drain current by using the generated layout output parameter of a BSIM 4 advanced analyzer. The simulated results of the proposed adder-based multiplier circuit are compared with a cell multiplier that utilizes a MCIT-based adder, a cell multiplier composed of complementary pass transistor logic-based (CPL) adders and those of other published multipliers circuits. From the analysis of these simulated results, it was found that the proposed multiplier circuit gives better performance in terms of power, propagation delay, latency and throughput than other published results. 相似文献
992.
S. N. Singh R. Gandotra P. K. Singh B. C. Chakravarty 《Bulletin of Materials Science》2005,28(4):317-323
Minority carrier lifeline, τ, is one of the most important parameters which has a decisive effect on the performance of silicon
devices based on excess carriers. The value of τ is greatly affected by the presence of impurities and defects in silicon
and its value provides a fair indication of quality of the material. Photoconductivity decay (PCD) and photocurrent generation
(PCG) methods are simple and low cost methods of measurement of minority carrier lifetime in silicon wafers. However, their
application requires care. The PCD method can give quite misleading results in case of polycrystalline wafers if there exists
potential barriers at the grain boundaries which may affect majority carrier mobility significantly. PCG needs creation of
an inducedp
+-p-n
+ structure of substantially good quality that should not degrade with time. For PCG method the T measurement under vacuum
conditions provides correct and consistent results. 相似文献
993.
Ripening affects the quality and nutritional contents of fleshy fruits. Mango, a climacteric fruit, is very susceptible to post-harvest losses, due to fast softening. In the present paper we report the effect of 1-methylcyclopropene (1-MCP) and Ethrel on antioxidant levels in mango fruit during ripening. Use of 1-MCP is applied commercially to delay ripening while Ethrel is used to accelerate ripening of climacteric fruits. 1-MCP treatment led to decreased levels of H2O2 and lipid peroxidation, concomitant with increased activities and isozymes of catalase (CAT) and superoxide dismutase (SOD), as compared to respective controls. On the other hand, Ethrel treatment led to an increase in H2O2 and lipid peroxidation, concomitant with a decrease in the activities and isozymes of catalase and SOD. Guaiacol peroxidase (GPX) could not be detected in the control or in treated fruits. Activity of ascorbate peroxidase (APX) was found to drastically increase in the presence of Ethrel while 1-MCP treatment led to only a marginal increase in APX. 相似文献
994.
Air flow through a solar-cum-wind aspirator is induced by both thermal buoyancy and wind effects. A similitude study has been conducted to characterize air flow rates through solar-cum-wind aspirators. A relationship between the air flow rate and height and diameter of the aspirator, wind speed, temperature rise inside the stack, and relevant air properties has been developed on the basis of the experimental data collected under field conditions. 相似文献
995.
This paper deals with cost analysis of a single server two-unit (one priority and the other ordinary) cold standby system with two modes—normal and total failure. A switch is used to operate the standby unit (ordinary) and it works successfully with known probability p( = 1 ? q). Priority unit gets preference both for operation and repair. Failure and repair time distributions are arbitrary. System fails when switch or both the units fail totally. The system is observed at suitable regenerative epochs in order to obtain reliability characteristics of interest to system designers and operations managers. Explicit results for the exponential time distributions have been obtained in particular cases. 相似文献
996.
997.
A simple concentric cylinder model is developed for the fibre push-out test in order to interpret the experimentally observed indenter load-displacement curves in ceramic-matrix composites. The fibre-matrix interface is assumed to be partially bonded and partially frictionally coupled. It is shown that a slope change in the loading curve corresponds to bonding at the fibre-matrix interface. In contrast an insignificant change in the slope is predicted for composites in which the fibre-matrix interface is frictionally coupled. This model also provides a framework for determining the interfacial debond energy and the interfacial shear strength in ceramic composites using the fibre push-out tests. The predictions of this model are compared with the push-out test results performed on zircon-SiC composites uniaxially reinforced with either uncoated or BN-coated SiC monofilaments, which suggested that the fibre-matrix interfaces in both of these composites are frictionally coupled. 相似文献
998.
Background
The ability to reduce inflammation in overweight and obese individuals may be valuable in preventing the progression to metabolic syndrome with associated risks for heart disease and diabetes. The purpose of this study was to evaluate the effect of multiple dosages of a proprietary Mangosteen Juice blend on indicators of inflammation and antioxidant levels in obese patients with elevated C-reactive protein (CRP) levels. 相似文献999.
We investigated the mobility and distribution of cadmium (Cd), nickel (Ni) and zinc (Zn) in four contaminated soil profiles
from Bangladesh. The sources of contamination of these profiles were tannery wastes, city sewage and the wastes of pharmaceutical
and paper mill factories at different locations in Bangladesh. The samples were collected from the A-, B- and C-horizons of
each profile: two sub-samples from the A-horizon at depths of 0–5 cm (A1) and >5 cm (A2), and one sample each from the B-
and C-horizons. Soil samples were analysed for total metal content by dissolution in aqua regia followed by sequential extraction
of the fractions based on their varying solubility. There were six operationally defined groups of extraction sequences: water
soluble (F1), exchangeable (F2), carbonate (F3), oxide (F4), organic (F5) and residual (F6). The total concentration of Cd,
Ni and Zn in the A-horizon (0–5 cm) ranged from 0.10 to 0.62, from 31 to 54 and from 85 to 838 mg kg−1, respectively. In the B- and C-horizons, the concentrations of these metals decreased many fold, particularly in the city
sewage profile where the decrease for Cd and Zn was approximately fourfold. The distribution of metals among the chemical
fractions depended on their total concentrations. In the A1-horizon, Cd had the highest mobility factor [MF = (F1+F2+F3)/(F1+F2+F3+F4+F5+F6) × 100]
at 41–43% and Ni had the lowest at 3–13%, while Zn, showed intermediate values at 8–25%. The MF decreased with depth in all
soil profiles. Among the fractions, the residual fraction contained the lowest levels of Cd but the highest levels of Ni and
Zn. This state affected their relative mobility and distribution in soil profiles. Of the soil profiles, the mobility of all
metals was higher in the city sewage soil than in any of the other three soils investigated, suggesting that the former may
create a health risk by contaminating agricultural products and ground water as it also contained higher amounts of Cd and
Zn. 相似文献
1000.
Virpal Singh V. N. Singh Ashok Mittal 《Journal of Infrared, Millimeter and Terahertz Waves》2000,21(3):421-428
This paper describes the Integrated Finline Front-end Radar Receivers at Ka-Band. The Front-receivers developed for Radar applications include combining of finline components on a single MIC substrate with various planar transmission lines. The integrated systems so developed have better noise figure and control over phase and gain imbalances as compared to discrete component systems. Two types of Integrated Front-ends Radar receivers are described here. The developed systems are highly compact and reliable. 相似文献