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991.
特大型全纤维台车式电阻炉设计 总被引:1,自引:0,他引:1
介绍了自行设计、制造的大型全纤维台车式电阻炉的总体设计方案。该炉经试运行表明,具有隔热性能好、操作方便、温度控制平稳等优点,可满足热处理工艺的要求。 相似文献
992.
E. A. Salgansky V. M. Kislov S. V. Glazov A. F. Zholudev G. B. Manelis 《Combustion, Explosion, and Shock Waves》2008,44(3):273-280
Superadiabatic regimes of combustion of carbon mixed with an inert solid with filtration of the steam-air mixture are studied
theoretically and experimentally. The temperature in the combustion wave and the composition of gaseous products are obtained
as functions of the fraction of carbon in the fuel and the amount of steam in the gaseous oxidant. In the examined range of
the control parameters, the maximum temperature in the combustion wave is shown to depend only slightly on the fraction of
carbon in the mixture and the amount of steam in the oxidant gas. Simulations of filtration combustion of carbon with allowance
for the kinetics of its oxidation are in good agreement with experimental results. The calculated combustion temperature coincides
with that measured in experiments. In calculating the composition of the gaseous products, coincidence with experimental data
is observed only for particular compositions with the mass content of carbon under 60%. As the fraction of the fuel exceeds
60%, the yield of CO and H2 increases in experiments, though such a behavior is not predicted by the theoretical analysis. Hypotheses on the reasons
for the disagreement in results are put forward and experimentally checked.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 3, pp. 30–38, May–June, 2008. 相似文献
993.
994.
995.
45钢脉冲放电超快速加热淬火 总被引:5,自引:2,他引:3
利用电容器组脉冲放电装置对45钢施行快速加热淬火,加热速度可达10^6℃/s,功率密度可达10^5/cm^2,试验表明,脉冲放电淬火法是实现超快速加热的好方法,具有一定的实用价值。 相似文献
996.
ABSTRACT A numerical solution of the diffusion equation to describe solute transport inside ellipsoids, assuming a constant difiusion coefficient and a corrective boundary condition, is presented. The difiusion equation in a prolate spheroidal coordinate system was used for a hidimensional case. The finite volume method was employed to discretize the basic equation, utilizing a uniform grid size. The equation was solved irteratively using the Gauss-Seidel method. The effect of Biot number and the aspect ratio of the body on diffusion rate and concentration during the process is presented. Plots are presented for Biot numbers from 0.05 to infinity and aspect ratios of 1.1, 2.0 and 5.0. To investigate the effect of the aspect ratio, different results changing the aspect ratio for Bi= 1.0 are shown. The results show that the model is consistent and it may be used to solve other cases such as those that include cylinder and sphere geometry, and/ or those with variable diffusion coefficients with small modifications. 相似文献
997.
998.
In 2007 Ireland supplied 96% of the total energy demand with fossil fuels (7% domestic and 89% imported) and 3% with renewable energy, even though there are enough renewable resources to supply all the energy required. As energy prices increase and the effects of global warming worsen, it is essential that Ireland begins to utilise its renewable resources more effectively. Therefore, this study presents the first step towards a 100% renewable energy-system for Ireland. The energy-system analysis tool used was EnergyPLAN, as it accounts for all sectors of the energy-system that need to be considered when integrating large penetrations of renewable energy: the electricity, heat, and transport sectors. Initially, a reference model of the existing Irish energy-system was constructed, and subsequently three different 100% renewable energy-systems were created with each focusing on a different resource: biomass, hydrogen, and electricity. These energy-systems were compared so that the benefits from each could be used to create an ‘optimum’ scenario called combination. Although the results illustrate a potential 100% renewable energy-system for Ireland, they have been obtained based on numerous assumptions. Therefore, these will need to be improved in the future before a serious roadmap can be defined for Ireland’s renewable energy transition. 相似文献
999.
F. Pellemoine W. MittigM. Avilov D. IppelJ. Lenz J. OlivaI. Silverman D. YouchisonT. Xu 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,655(1):3-9
One of the major challenges of the FRIB project (Facility for Rare Isotope Beams) at Michigan State University is the design and integration of the production target to produce rare isotope beams via fragmentation reaction. In the most extreme case, a 400 kW uranium beam of 200 MeV/u will be focused in a 1 mm diameter spot, leading to a power density of 60 MW/cm3 for a C target. Up to 200 kW may be dissipated in the target.A rotating solid carbon disk concept has been selected as the target design approach for all primary beams up to uranium to provide high-power operation. A high rotational speed is necessary to compensate for the high power density. A multi-slice approach allows the evacuation of the large amount of heat deposited by the increase of the radiating area. In the present design study, the multi-slice target device has a diameter of about 30 cm and rotates at about 5000 RPM (revolutions per minute). The first step of the R&D strategy consists in the development and test of a 20 kW single-slice target prototype. This single disk device is designed to accept the same fraction of power as each disk of the final multi-slice target. Critical information on thermal-mechanical properties can be obtained thus at a lower power level than the one of the full device. Different carbon materials were tested. An electron beam of ∼20 keV was used for the thermal tests. Simulations were performed using the ANSYS code for the thermo-mechanical behaviour of the target, the resulting deformation and the stress profiles of heated graphite disks. Results of the simulations were compared with experimental data. 相似文献
1000.
The thermal dissipation of radiation is main heat shield mechanism for non-ablative thermal protection materials on hypersonic vehicles withstanding high temperature dynamic heating cycle during endo-atmospheric ascent, cruise and reentry. Therefore, it is necessary to know the thermal radiative properties of the material under the simulated high temperature dynamic heating conditions on the ground. The emissivity depends on the surface state and its temperature. A new simultaneous measurement technology of emissivity and varying surface temperature is proposed under high temperature dynamic heating conditions. This new technology solved synchronous measurement problems by utilizing spectral signal of Fourier transform infrared (FTIR) spectroscopy. The calibration of different temperature ranges, the background disturbances, the influences on temperature measurement by wavelength range and its corresponding fluctuations of measurement signal, were thoroughly investigated. The measured results of steel and graphite as reference materials proved the effectiveness of this simultaneous measurement technology and showed great potential in engineering applications under high temperature dynamic heating conditions. 相似文献