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101.
102.
Results are presented on the construction of a thin‐layer photovoltaic cell on glass‐fiber fabric. The unevenness of the fabric was first smoothed by the application of a high‐temperature stable resin before photovoltaic layer deposition. We obtained an efficiency of light‐to‐current conversion of more than 8%. This constitutes a remarkably high value for a photovoltaic cell on a flexible substrate. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
103.
Bartosz Krajnik Magdalena Gajda-R?czka Dawid Pi?tkowski Piotr Nyga Bart?omiej Jankiewicz Eckhard Hofmann Sebastian Mackowski 《Nanoscale research letters》2013,8(1):146
In this work we demonstrate enhancement of the fluorescence collection efficiency for chlorophyll-containing photosynthetic complexes deposited on SiO2 spherical nanoparticles. Microscopic images of fluorescence emission reveal ring-like emission patterns associated with chlorophyll-containing complexes coupled to electromagnetic modes within the silica nanoparticles. The interaction leaves no effect upon the emission spectra of the complexes, and the transient behavior of the fluorescence also remains unchanged, which indicates no influence of the silica nanoparticles on the radiative properties of the fluorophores. We interpret this enhancement as a result of efficient scattering of electromagnetic field by the dielectric nanoparticles that increases collection efficiency of fluorescence emission. 相似文献
104.
Ramesh Chandra Mallik Christian Stiewe Gabriele Karpinski Ralf Hassdorf Eckhard Müller 《Journal of Electronic Materials》2009,38(7):1337-1343
The properties of Co4Sb12 with various In additions were studied. X-ray diffraction revealed the presence of the pure δ-phase of In0.16Co4Sb12, whereas impurity phases (γ-CoSb2 and InSb) appeared for x = 0.25, 0.40, 0.80, and 1.20. The homogeneity and morphology of the samples were observed by Seebeck microprobe and scanning
electron microscopy, respectively. All the quenched ingots from which the studied samples were cut were inhomogeneous in the
axial direction. The temperature dependence of the Seebeck coefficient (S), electrical conductivity (σ), and thermal conductivity (κ) was measured from room temperature up to 673 K. The Seebeck coefficient of all In-added Co4Sb12 materials was negative. When the filler concentration increases, the Seebeck coefficient decreases. The samples with In additions
above the filling limit (x = 0.22) show an even lower Seebeck coefficient due to the formation of secondary phases: InSb and CoSb2. The temperature variation of the electrical conductivity is semiconductor-like. The thermal conductivity of all the samples
decreases with temperature. The central region of the In0.4Co4Sb12 ingot shows the lowest thermal conductivity, probably due to the combined effect of (a) rattling due to maximum filling and
(b) the presence of a small amount of fine-dispersed secondary phases at the grain boundaries. Thus, regardless of the non-single-phase
morphology, a promising ZT (S
2
σT/κ) value of 0.96 at 673 K has been obtained with an In addition above the filling limit. 相似文献
105.
Lage E Kirchhof C Hrkac V Kienle L Jahns R Knöchel R Quandt E Meyners D 《Nature materials》2012,11(6):523-529
Magnetoelectric composite materials are promising candidates for highly sensitive magnetic-field sensors. However, the composites showing the highest reported magnetoelectric coefficients require the presence of external d.c. magnetic bias fields, which is detrimental to their use as sensitive high-resolution magnetic-field sensors. Here, we report magnetoelectric composite materials that instead rely on intrinsic magnetic fields arising from exchange bias in the device. Thin-film magnetoelectric two-two composites were fabricated by magnetron sputtering on silicon-cantilever substrates. The composites consist of piezoelectric AlN and multilayers with the sequence Ta/Cu/Mn(70)Ir(30)/Fe(50)Co(50) or Ta/Cu/Mn(70)Ir(30)/Fe(70.2)Co(7.8)Si(12)B(10) serving as the magnetostrictive component. The thickness of the ferromagnetic layers and angle dependency of the exchange bias field are used to adjust the shift of the magnetostriction curve in such a way that the maximum piezomagnetic coefficient occurs at zero magnetic bias field. These self-biased composites show high sensitivity to a.c. magnetic fields with a maximum magnetoelectric coefficient of 96 V cm(-1) Oe(-1) at mechanical resonance. 相似文献
106.
Eduardo Navarro de Andrade Eric Skowron Victor W. Goldschmidt Eckhard A. Groll 《International Journal of Refrigeration》1999,22(6):499
The concentration of oil in refrigerants (while in liquid state) can be measured with an acoustic velocity sensor. The transit time for an acoustic signal can be related to the oil concentration and temperature of the liquid mixture. The performance of the sensor is dependent on the properties of the oil and refrigerant, and their miscibility. In general, a thorough calibration becomes necessary. It is shown in this paper that for concentrations less than 10%, an approximation can be made for the estimate of concentration hence eliminating the need for an elaborate calibration procedure. 相似文献
107.
108.
Organic Tube/Rod Hybrid Nanofibers with Adjustable Segment Lengths by Bidirectional Template Wetting
O. Kriha L. Zhao E. Pippel U. Gösele R. B. Wehrspohn J. H. Wendorff M. Steinhart A. Greiner 《Advanced functional materials》2007,17(8):1327-1332
Segmented nanotubes and nanorods exhibiting a variation in their composition along their long axes represent a new and exciting class of nanomaterials. It is shown that bidirectional template wetting enables the integration of functional and complex polymeric materials into segmented nanofibers. First, a template is wetted under conditions in which a solid polymeric thread with adjustable length fills a pore segment starting from one template surface. Subsequently, a second wetting step starting from the opposite template surface yields segmented nanofibers. The exploitation of different wetting mechanisms results in the formation of tube/rod hybrid nanofibers. 相似文献
109.
Mark Bertram Corrine Manschot‐Lawrence Eckhard Flöter Uwe T. Bornscheuer 《European Journal of Lipid Science and Technology》2007,109(2):180-185
A microtiter plate (MTP) method was developed to determine the quality of fats that are used in large‐scale processing using lipase catalysis. Two assay formats were followed: In the first approach, the fats were interesterified with p‐nitrophenol laurate using a lipase from Thermomyces lanuginosa; in the second approach, pH indicators were added to the fat samples containing lipase. A blind study using 29 fats showed that the MTP method using p‐nitrophenol as pH indicator allowed a rapid and reliable assignment of bad fats and an acceptable differentiation between fats of moderate and good quality. 相似文献
110.
This article introduces a new high-pressure process for the gentle drying, micronisation and formulation of high molecular mass gelatine. Spray drying of gelatine solutions is a well-established process for very low molecular weight gelatine, aqueous solutions containing low gelatine concentrations or gelatine solutions containing viscosity reducing additives. In the introduced process, supercritical CO2 was applied to micronised aqueous gelatine solutions and was then expanded from high pressure into a spraying chamber to remove the water content by extraction and evaporation under moderate conditions. The resulting product was analysed using common powder analysis methods. Aqueous gelatine solutions with a dry mass content of up to 50 wt.% with a molecular mass of 156,000 g mol?1 were pulverised and dried with this process, with only limited degradation by hydrolysis during processing. 相似文献