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121.
Correlation of structural characterization and viscosity measurements with total unsaturation: An effective method for controlling ozonation in the preparation of ozonated grape seed and sunflower oils
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122.
Machine Translation - Self-attention-based encoder-decoder frameworks have drawn increasing attention in recent years. The self-attention mechanism generates contextual representations by attending... 相似文献
123.
K.R. Acchutharaman N. Santhosh R. Isaac Daniel Muthu Senthil Pandian P. Ramasamy 《Ceramics International》2021,47(15):21263-21270
Titanium dioxide (TiO2) nanoparticles (NPs) were synthesized through solvothermal route by changing the rate of hydrolysis in the catalytic process. In order to change the hydrolysis rate, the concentration of acetic acid, as additive, was varied as 2 M, 3 M and 4 M. The synthesized NPs were examined by various physico-chemical characterization techniques. The powder X-ray diffraction (PXRD) analysis of the NPs reveals only the anatase phase of TiO2. The spherical shaped morphology of the NPs was observed in the high-resolution transmission electron microscopy (HR-TEM) analysis. The optical behaviour such as absorption, bandgap, diffuse reflectance and photoluminescence (PL) emission of the NPs were studied. The material's nature and behaviors were scrutinized and they were employed as photoanode in dye sensitized solar cell (DSSC) and as electron transport layer (ETL) in carbon-based perovskite solar cell (C-PSC). The charge transfer at the interface of the devices was studied with electrochemical impedance spectroscopy (EIS). The fabricated DSSC and C-PSC show highest power conversion efficiency (PCE) of 6.1% and 10.6%, respectively. The highest current collection was detected in C-PSC and the results are discussed in detail. 相似文献
124.
Mauro Zammarano John R. Shields Isaac Leventon Ickchan Kim Shonali Nazare Andre Thompson Rick D. Davis Artur Chernovsky Matthew Bundy 《火与材料》2021,45(1):114-126
Herein, we describe a reduced‐scale test (“Cube” test), measuring the fire performance of specimens including a fire barrier (FB) and a flammable core material, which acts as the main fuel load. The specimen is intended to reproduce a cross‐section of a composite product where heat/mass transfer occurs primarily in a direction perpendicular to the FB. The Cube test procedure and benefits are discussed in this work by adopting residential upholstery furniture as an exemplary study. One flexible polyurethane foam, one polypropylene cover fabric, and 10 commercially available FBs were selected. They were used to compare the fire performance of FBs, measured in terms of peak of heat release rate, in the ASTM E1474‐14 standard test and the newly developed Cube test. Edge effects severely affected the performance of FBs in the ASTM E1474‐14 standard test but not in the Cube test. Furthermore, appropriate test conditions were determined in the Cube test to measure the so‐called “wetting point,” that is, the time and value of heat release rate measured when flammable liquid products were first observed on the bottom of the specimen. The relevance of the “wetting point” in terms of full‐scale fire performance and failure mechanism of FBs is discussed. 相似文献
125.
126.
de Diego Isaac Martín Román Ignacio San Montero Javier Cano Conde Cristina Cabello Enrique 《Multimedia Tools and Applications》2019,78(13):17437-17459
Multimedia Tools and Applications - This paper presents a novel distributed intelligent video surveillance architecture based on Wireless Multimedia Sensor Networks (WMSNs). This architecture is... 相似文献
127.
A methodology for predicting and comparing the full‐scale fire performance of similar materials based on small‐scale testing
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Reconstructive fire testing is an important tool used by fire investigators to determine the cause, origin, and progression of a particular fire. Accurate reconstruction of the fire requires the laboratory structure to be outfitted with materials that, in terms of contribution to fire growth, perform similarly to the original materials found at the fire scene. Therefore, a procedure was developed to enable fire investigators to select these replacement materials on the basis of a quantitative assessment of their relative fire performance. This procedure consists of gram‐scale and/or milligram‐scale standard testing accompanied by inverse numerical modeling of these tests, which is used to obtain relevant material properties. A numerical model composed of a detailed pyrolysis submodel and empirical flame heat feedback submodels, which were developed in this study, is subsequently employed to simulate the early stages of the Room Corner Test, which was selected to represent full‐scale material performance. The results of these simulations demonstrate that this procedure can successfully differentiate between fire growth propensities of several commercially available medium density fiberboards. 相似文献
128.
Isaac Monroy Péter Bakonyi Germán Buitrón 《Clean Technologies and Environmental Policy》2018,20(7):1581-1588
Continuous hydrogen production stability and robustness by dark fermentation were comprehensively studied at laboratory scale. Continuous bioreactors were operated at two different hydraulic retention times (HRT) of 6 and 10 h. The reactors were subjected to feeding shocks given by decreases in the HRT, and therefore the organic loading increases, during 6 and 24 h. Results indicated that the H2 productivity was significantly improved by the temporary organic shock loads, increasing the hydrogen production rate up to 40%, compared to the rate obtained at the steady-state condition. Besides, it was observed that after the shock load, the stability of the reactor (measured as the hydrogen production rate) was recovered attaining the values observed before the feeding shocks. The bioreactor operated at shorter HRT (6 h) showed better H2 productivity (17.3?±?1.1 L H2/L-d) in comparison with the other one operated at 10-h HRT (12.4?±?1.6 L H2/L-d). 相似文献
129.
130.
Paul E. Barbone Navid Nazari Isaac Harari 《International journal for numerical methods in engineering》2019,120(8):1027-1046
The propagation of waves in elastic solids at or near the incompressible limit is of interest in many current and emerging applications. Standard low-order Galerkin finite element discretization struggles with both incompressibility and wave dispersion. Galerkin least squares stabilization is known to improve computational performance of each of these ingredients separately. A novel approach of combined pressure-curl stabilization is presented, facilitating the use of continuous, equal-order interpolation of displacements and pressure. The pressure stabilization parameter is determined by stability considerations, while the curl stabilization parameter is determined by dispersion considerations. The proposed pressure-curl–stabilized scheme provides stable and accurate results on a variety of numerical tests for incompressible and nearly incompressible elastic waves computed with linear elements. 相似文献