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排序方式: 共有532条查询结果,搜索用时 15 毫秒
1.
I. D. Kashcheev S. N. Sychev M. N. Dunaeva L. A. Karpets P. A. Emel’yanov O. S. Ryakhova 《Refractories and Industrial Ceramics》2008,49(2):131-134
Compositions have been developed for nonshrinking vibrocast thermally insulating light refractory concretes with densities
of 1.0, 1.3, 1.5, and 1.8 g/cm3 for temperatures of use up to 1400°C. The structure and properties have been examined for the concrete of density 1.3 g/cm3.
__________
Translated from Novye Ogneupory, No. 4, pp. 29–32, April, 2008. 相似文献
2.
M. O. Petrushkov M. A. Putyato I. B. Chistokhin B. R. Semyagin E. A. Emel’yanov M. Yu. Esin T. A. Gavrilova A. V. Vasev V. V. Preobrazhenskii 《Technical Physics Letters》2018,44(7):612-614
An original technology of zinc diffusion into InP via a narrow gap is described, which allows reproducible formation of p–n junctions with preset depth of doping and retained surface morphology of the doped layers. Using the proposed method, desired charge carrier distribution profiles in Zn-doped InP layers were obtained. It has been experimentally confirmed that the method of cross-sectional scanning electron microscopy allows to precision measure of the zinc diffusion depth. 相似文献
3.
A. Oral S. J. Bending R. G. Humphreys M. Henini 《Journal of Low Temperature Physics》1996,105(5-6):1135-1140
We have used a low noise Scanning Hall Probe Microscope (SHPM) to study vortex structures in superconducting films. The microscope has high magnetic field (2.9×10–8T/Hz at 77K) and spatial resolution, 0.85m. Magnetic field profiles of single vortices in High Tc YBa2Cu3O7– thin films have been successfully measured and the microscopic penetration depth of the superconductor has been extracted as a function of temperature. Flux penetration into the superconductor has been imaged in real time (8s/frame). 相似文献
4.
5.
Micro-milling performance of AISI 304 stainless steel using Taguchi method and fuzzy logic modelling
In this study, micro-milling of AISI 304 stainless steel with ball nose end mill was conducted using Taguchi method. The influences of spindle speed, feed rate and depth of cut on tool wear, cutting forces and surface roughness were examined. Taguchi’s signal to noise ratio was utilized to optimize the output responses. The influence of control parameters on output responses was determined by analysis of variance. In this study, the models describing the relationship between the independent variables and the dependent variables were also established by using regression and fuzzy logic. Efficiency of both models was determined by analyzing correlation coefficients and by comparing with experimental values. The results showed that both regression and fuzzy logic modelling could be efficiently utilized for the prediction of tool wear, cutting forces and surface roughness in micro-milling of AISI 304 stainless steel. 相似文献
6.
V. F. Savchenko L. V. Makhnach I. I. Emel’yanova V. V. Pan’kov 《Inorganic Materials》2006,42(7):788-793
The formation of LaSrNiO4-and LaSrScO4-based solid solutions with the general stoichiometry LaSrNi1 ? x ScxO4 (0 < x < 1) has been studied in air at temperatures from 700 to 1300°C. According to x-ray diffraction results, the former solid solutions exist in the composition range 0 < x ≤ 0.2. Their lattice parameters have been determined, and their resistivity and thermoelectric power have been measured as functions of temperature. Oxygen release and absorption measurements at temperatures from 20 to 1000°C and oxygen partial pressures from 2 to 330 Pa suggest that the presence of scandium has a stabilizing effect on the oxygen sublattice of the solid solutions. The possible mechanisms of this effect are discussed. 相似文献
7.
Experimental investigation of the current-induced breakage of metal-coated polymer films 总被引:1,自引:0,他引:1
We have experimentally studied the phenomenon of current-induced breakage of thin (∼20-to 30-nm-thick) metal films deposited
onto poly(ethylene terephthalate) (PETP) and poly(propylene) (PP) substrates. Two mechanisms leading to the current-induced
breakage of the metal film are established, which are characterized by different average threshold current densities: j
H ∼ 1.5 × 1010 A/m2 and j
L ∼ 0.7 × 1010 A/m2. The possible nature of these mechanisms is discussed. 相似文献
8.
A. M. Emel’yanov 《Semiconductors》2013,47(1):110-115
The experimental results and model representations of the edge electroluminescence of two published studies for small-area silicon p +-n diodes heavily doped with boron are analyzed. In one of these studies it was assumed that edge electroluminescence appears in the p + region of the diode, and in the other, in the n region of the diode. In the latter case, it was demonstrated that electroluminescence indeed arose in the n region and was caused predominantly by the radiative recombination of free excitons. It is shown that similar model concepts are also applicable to the other study. Based on several independent experimental studies (of edge photoluminescence, electroluminescence, and radiation absorption by free carriers), it is demonstrated that the linear or close-to-linear dependences of the edge-luminescence intensity on the excitation intensity, observed in single-crystal silicon at high injection levels, are caused by the close-to-linear dependences of the exciton concentration on the free-carrier concentration. The results of this study extend the capability of luminescence methods for determining the carrier lifetimes to the region of high injection levels. 相似文献
9.
V. I. Melik-Gaikazyan N. P. Emel’yanova D. V. Dolzhenkov 《Russian Journal of Non-Ferrous Metals》2014,55(4):309-317
The energy possibility of the transition of free bubbles A to adherent bubbles M, or the A → M (TAM) transition, is calculated on substrates with different wetting abilities: extremely hydrophilic (Φ), extremely hydrophobic (Γ), and with incomplete wetting ability (H x ), where x is the substrate surface fraction covered by a monolayer of collector molecules). Calculations of TAM for bubbles with a diameter (d e ) of 2 mm to 20 nm on Φ, Γ, and H x substrates showed that the change in specific energy (ΔG/V) in a bubble in the case of TAM depends on the value of d e , substrate wetting ability, and surface area of its contact with the bubble. According to the results of studies, high capillary pressure (P c) in nanobubbles M promotes their instantaneous spreading over the substrate. Herewith, P c decreases considerably. The adhesion and spreading processes occur as a single process, irreversibly, one-way, and fast, because they are not complicated by counterprocesses. Upon a decrease in equatorial diameter d e and wetting ability of the substrate, the decrease in G/V reaches several million J/m3. The actual simultaneity of the processes of bubble adhesion and spreading is illustrated by microphotographs of larger bubbles with a luminescent apolar reagent eliminating the effect of wetting hysteresis that is easily overcome in nanobubbles in the case of high P c values. 相似文献
10.
S. A. Blokhin A. M. Nadtochiy S. A. Mintairov N. A. Kalyuzhny V. M. Emel’yanov V. N. Nevedomsky M. Z. Shvarts M. V. Maximov V. M. Lantratov N. N. Ledentsov V. M. Ustinov 《Technical Physics Letters》2012,38(11):1024-1026
Results of a comparative study of the internal quantum yield of AlGaAs/GaAs photovoltaic converters (PVCs) with variable position of the array of vertically coupled InGaAs quantum dots (QDs) are presented. It is established that the QD array placed immediately at the i-region/base interface does not change the PVC sensitivity compared to that for QDs arranged inside the i-region of the p-n junction. However, the QD array shifted to the base or the back potential barrier decreases the contribution of a base layer to the PVC photocurrent and reduces the photosensitivity of the QD-based medium. 相似文献