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161.
The possibility is demonstrated of using an addition of periclase-chromite filler (PCF) prepared from PCF grade broken material
articles in medium-cement concrete with chamotte filler. The effect of this addition on cement hardening duration, strength
and heat resistance is considered.
Translated from Novye Ogneupory, No. 8, pp. 42–46, August 2008. 相似文献
162.
Programs are presented for calculating dusty air flow in ventilation systems, which have been derived from the method of singular
integral equations. They allow one to construct flow lines and determine the velocity pattern for the air in a closed rectangular
region with outlet, flow, and extraction holes; a study is made on the dust particle behavior in the aerodynamic field in
which there may be a rotating cylinder or pumping cylinder; determinations are made of the concentration and grain-size composition
of the dust in the extraction hole; one can construct flow lines and single-particle paths in multicoupled regions of potential
flows containing any number of rotating cylinders and cylinder pumps.
Translated from Novye Ogneupory, No. 5, pp. 53–58, May, 2008. 相似文献
163.
A very important characteristic of coking coal is its clinkering ability, i.e., its ability to form a nonvolatile solid residue, consisting of disparate grains, on heating in specific conditions. The clinkering ability of the coal is determined by the properties of its plastic mass. Various methods may be used to evaluate the plastic-ductile properties of the coal. However, since the 1930s, the main method used to evaluate the clinkering properties of coal, within the nations of the former Soviet Union, has been the Sapozhnikov-Bazilevich plastometric method, because it provides more information than competing approaches. For the same reason, the thickness of the plastic layer, which is one of the parameters determined by this method, is used for coal classification in State Standard GOST 25543-88 (Lignite, Coal, and Anthracite: Genetic and TEchnological Classification) and its Ukrainian counterpart DSTU 3472-96 (Lignite, Coal, and Anthracite: Classification). This explains the strict requirements on the accuracy and reliability of the plastometric characteristics. 相似文献
164.
A technique is proposed for introducing microdoses (10?5–10?10 g) of germanium and indium metals into semiconductor compounds by coulometric titration in a solid electrolyte cell. The solid electrolytes that are reversible with respect to germanium cations (the GeSe-GeI2 system containing 5 mol % GeI2) and indium cations (the InCl3-MgCl2 system containing 15 mol % MgCl2, the InCl3-CdCl2 system containing 1.5 mol % CdCl2, and the In2S3-InCl3 system containing 5 mol % InCl3) are chosen, and their electric transport properties are characterized. The optimum conditions for electrochemical doping (temperature, current density), under which the current efficiency reaches 90–100%, are determined. The doping with germanium and indium is performed for nonstoichiometric compounds, such as lead monotelluride, indium sulfide, and ternary chalcogenide spinel Cd1 ± δCr2Se4. The doping efficiency is controlled by measuring the electromotive force of the corresponding electrochemical cells and the Hall effect, as well as using the electrical conductivity method. The solid electrolytes that are reversible with respect to indium are used to determine the standard Gibbs energies of formation of a number of indium-containing semiconductors. 相似文献
165.
166.
J.A. Giroto A.C.S.C. Teixeira C.A.O. Nascimento R. Guardani 《Chemical Engineering and Processing: Process Intensification》2008,47(12):2361-2369
This paper presents the results of experiments carried out in a laboratory-scale photochemical reactor on the photodegradation of different polymers in aqueous solutions by the photo-Fenton process. Solutions of three polymers, polyethyleneglicol (PEG), polyacrylamide (PAM), and polyvinylpyrrolidone (PVP), were tested under different conditions. The reaction progress was evaluated by sampling and analyzing the total organic carbon concentration in solution (TOC) along the reaction time. The behavior of the different polymers is discussed, based on the evolution of the TOC–time curves. Under specific reaction conditions, the formation and coalescence of solid particles was visually observed. Solids formation occurred simultaneously to a sharp decrease in the TOC of the liquid phase. This may be favorable for the treatment of industrial wastewater containing polymers, since the photodegradation process can be coupled with solid separation systems, which may reduce the treatment cost. 相似文献
167.
Vjacheslav V. Zuev 《Journal of Polymer Research》2008,15(5):351-356
Functionalized polyanilines containing biphenyl, terphenyl, carbazole, anthracene, and 4-n-hexylphenyl moieties were synthesized though the reaction of polyaniline in emeraldine base form with sodium salt of corresponding
vinylketoaromatics with quantitative yields. Polymers were characterized with Fourier transform infrared spectroscopy, proton
nuclear magnetic resonance spectroscopy, and thermogravimetry. The emission characteristics of these polymers in N-methyl-2-pyrrolidone solution were examined. The functionalized polyanilines exhibited an intense green emission. 相似文献
168.
The results of computer simulations demonstrate the possibility of light energy transmission through band gaps of a one-dimensional photonic crystal with fluctuating lengths of individual layers. In the case of weak (±5%) fluctuations, the light pulse energy partly penetrates in depth a photonic crystal. If fluctuations of the layer length are strong (±20%), the light pulse energy can be partly transmitted through the crystal. 相似文献
169.
This paper presents the mass transfer results from an impinging liquid jet to a rotating disk. The mass transfer coefficients were measured using the electrochemical limiting diffusion current technique (ELDCT). Rotational Reynolds number (Rer) in the range of 3.4 × 104–1.2 × 105, jet Reynolds number (Rej) 1.7 × 104–5.3 × 104 and non-dimensional jet-to-disk spacing (H/d) 2–8 were taken into consideration as parameters. It was found that the jet impingement resulted in a substantial enhancement in the mass transfer compared to the case of the rotating disk without jet. 相似文献
170.
During experiments on the MSL-1 (first microgravity science laboratory) mission of the space shuttle (STS-83 and STS-94, April
and July 1997), a droplet of palladium-silicon alloy was electromagnetically levitated for viscosity measurements. For the
nondeforming droplet, the resultant magnetohydrodynamic (MHD) flow inside the drop can be inferred from motion of impurity
particulates on the surface. In the experiments, subsequent to melting, Joule heating produces a continuous reduction of viscosity
of the fluid resulting in an acceleration of the flow with time. These observations indicate formation of a pair of co-rotating
toroidal flow structures inside the spheroidal drop that undergo flow instabilities. As the fluid temperature rises, the amplitude
of the secondary flow increases, and beyond a point, the tracers exhibit noncoherent chaotic motion signifying emergence of
turbulence inside the drop. Assuming that the observed laminar-turbulent transition is shear-layer type, the internal structure
of the toroidal loops is used to develop a semiempirical correlation for the onset of turbulence. Our calculations indicate
that the suggested correlation is in modest agreement with the experimental data, with the transition occurring at a Reynolds
number of 600. 相似文献