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In this work, an innovative procedure for real-time heat transfer modelling and dimensional change estimation during meat cooking was presented. By using a multipoint temperature probe, a punctual calculation of slowest heating point (SHP) temperature was obtained at each time from the radial temperature distribution inside the product. Experimental temperature data from the multipoint probe was combined with a mathematical algorithm previously validated to perform a real-time estimation of SHP temperature and residual cooking time on the basis of the data stored at each instant. The developed procedure and algorithm were validated by cooking pork loin and roast beef samples at 180 and 200 °C both under natural and forced convection regimes. Real-time predicted cooking time and SHP endpoint temperature values were very close to those experimentally obtained: at the 85% of the cooking process, the maximum percentage errors for SHP endpoint temperature and cooking time prediction were 1.72 and 1.67%, respectively. In addition, SHP location inside the meat samples was also obtained at each time instant and used to estimate dimensional changes during cooking: calculated final characteristic dimensions were very similar to those experimentally obtained for all cooking trials. The developed approach could be useful for the automatic cooking operations planning in food-service with microbial safety assurance. 相似文献
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Emma R. Power 《Housing Studies》2017,32(3):336-360
Companion animals are rarely considered in rental policy or research. This absence belies their prevalence and growing centrality within practices of family and home, and persists despite evidence of links between companion animals and rental insecurity. This paper begins to address this gap. Through an online survey and in-depth interviews with people who rented with companion animals in Sydney, Australia, over the 10 years to 2013, the paper identifies connections between pet ownership and rental insecurity, including perceptions about the low availability and poor quality of advertised ‘pet-friendly’ properties. The paper argues that pet ownership can trigger feelings of rental insecurity, and advocates for inclusion of pet ownership as a variable impacting secure occupancy. It suggests companion animals are an escalating rental risk, their significance to their owners causing some to accept accelerating levels of rental insecurity by keeping pets without landlord knowledge. These experience impact on the ability of renters to feel ‘at home’ in rental properties. 相似文献
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Emma Alexander Qi Guo Sanjeev Koppal Steven J. Gortler Todd Zickler 《International Journal of Computer Vision》2018,126(10):1062-1083
We present the focal flow sensor. It is an unactuated, monocular camera that simultaneously exploits defocus and differential motion to measure a depth map and a 3D scene velocity field. It does this using an optical-flow-like, per-pixel linear constraint that relates image derivatives to depth and velocity. We derive this constraint, prove its invariance to scene texture, and prove that it is exactly satisfied only when the sensor’s blur kernels are Gaussian. We analyze the inherent sensitivity of the focal flow cue, and we build and test a prototype. Experiments produce useful depth and velocity information for a broader set of aperture configurations, including a simple lens with a pillbox aperture. 相似文献
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Olga Becconi Emma Ahlstrand Andrea Salis Ran Friedman 《Israel journal of chemistry》2017,57(5):403-412
Specific interactions that depend on the nature of electrolytes are observed when proteins and other molecules are studied by potentiometric, spectroscopic and theoretical methods at high salt concentrations. More recently, it became clear that such interactions may also be observed in solutions that can be described by the Debye-Hückel theory, i.e., at physiological (0.1 mol dm−3) and lower concentrations. We carried out molecular dynamics simulations of bovine serum albumin in physiological solutions at T=300 and 350 K. Analysis of the simulations revealed some differences between LiCl solutions and those of NaCl and KCl. The binding of Li+ ions to the protein was associated with a negative free energy of interaction whereas much fewer Na+ and K+ ions were associated with the protein surface. Interestingly, unlike other proteins BSA does not show a preference to Na+ over K+. Quantum chemical calculations identified a significant contribution from polarisation to the hydration of Li+ and (to a lesser degree) Na+, which may indicate that polarisable force-fields will provide more accurate results for such systems. 相似文献
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Rachael Jaenke Federica Barzi Emma McMahon Jacqui Webster Julie Brimblecombe 《Critical reviews in food science and nutrition》2017,57(16):3357-3372
Food product reformulation is promoted as an effective strategy to reduce population salt intake and address the associated burden of chronic disease. Salt has a number of functions in food processing, including impacting upon physical and sensory properties. Manufacturers must ensure that reformulation of foods to reduce salt does not compromise consumer acceptability.The aim of this systematic review is to determine to what extent foods can be reduced in salt without detrimental effect on consumer acceptability.Fifty studies reported on salt reduction, replacement or compensation in processed meats, breads, cheeses, soups, and miscellaneous products. For each product category, levels of salt reduction were collapsed into four groups: <40%, 40–59%, 60–79% and ≥80%. Random effects meta-analyses conducted on salt-reduced products showed that salt could be reduced by approximately 40% in breads [mean change in acceptability for reduction <40% (?0.27, 95% confidence interval (CI) ?0.62, 0.08; p = 0.13)] and approximately 70% in processed meats [mean change in acceptability for reductions 60–69% (?0.18, 95% CI ?0.44, 0.07; p = 0.15)] without significantly impacting consumer acceptability. Results varied for other products.These results will support manufacturers to make greater reductions in salt when reformulating food products, which in turn will contribute to a healthier food supply. 相似文献