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991.
Jessica L. Axson Jessie M. Creamean Amy L. Bondy Sonja S. Capracotta Katy Y. Warner 《Aerosol science and technology》2013,47(1):24-34
Particles are frequently incorporated into clouds or precipitation, influencing climate by acting as cloud condensation or ice nuclei, taking up coatings during cloud processing, and removing species through wet deposition. Many of these particles, particularly ice nuclei, can remain suspended within cloud droplets/crystals as insoluble residues. While previous studies have measured the soluble or bulk mass of species within clouds and precipitation, no studies to date have determined the number concentration and size distribution of insoluble residues in precipitation or cloud water using in situ methods. Herein, for the first time we demonstrate that nanoparticle tracking analysis (NTA) is a powerful in situ method for determining the total number concentration, number size distribution, and surface area distribution of insoluble residues in precipitation, both of rain and melted snow. The method uses 500 μL or less of liquid sample and does not require sample modification. Number concentrations for the insoluble residues in aqueous precipitation samples ranged from 2.0–3.0 (±0.3)?×?108 particles cm?3, while surface area ranged from 1.8 (±0.7)–3.2 (±1.0) × 107 μm2 cm?3. Number size distributions peaked between 133 and 150 nm, with both single and multi-modal character, while surface area distributions peaked between 173 and 270 nm. Comparison with electron microscopy of particles up to 10 μm show that, by number, >97% residues are <1 μm in diameter, the upper limit of the NTA. The range of concentration and distribution properties indicates that insoluble residue properties vary with ambient aerosol concentrations, cloud microphysics, and meteorological dynamics. NTA has great potential for studying the role that insoluble residues play in critical atmospheric processes.Copyright 2015 American Association for Aerosol Research 相似文献
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Koss Shira; Clark Robin; Vesely Luisa; Weinstein Jessica; Powers Chivon; Richmond Lauren; Farag Christine; Gross Rachel; Liang Tsao-Wei; Grossman Murray 《Canadian Metallurgical Quarterly》2010,24(4):476
Objective: We assessed the representation of numerosity in corticobasal syndrome (CBS), a neurodegenerative condition affecting the parietal lobe. Method: Patients judged whether a target numerosity (e.g., “3”) falls between two bounding numerosities (e.g., “1” and “5”). We manipulated the format for representing numerosity (Arabic numerals or dot arrays), the size of the gap between the two bounding numerosities, the absolute magnitude of the numerosities, and the order for presenting the bounding numerosities. In a subset of patients with available imaging, we related performance to cortical atrophy using voxel-based morphometry. Results: CBS patients were significantly impaired overall (65.7% ± 16.2 correct) compared to healthy seniors (96.6% ± 2.4 correct), and required three times longer than controls to judge correct stimuli. This deficit was equally evident for Arabic numeral and dot array formats. Controls were significantly slower with smaller gaps than larger gaps, consistent with the greater challenge distinguishing between numerosities that are more similar to each other than very different numerosities. However, CBS patients were equally slow and inaccurate for all gap sizes. Controls also were significantly slower with larger numerosities than smaller numerosities, but CBS patients were equally slow and inaccurate with all numerosity magnitudes. Voxel-based morphometry revealed significant cortical atrophy in parietal and frontal regions in CBS compared to controls, including the intraparietal sulcus. Conclusions: These observations are consistent with the claim that the representation of numerosity is degraded in CBS. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Identification of landslide hazard and risk ‘hotspots’ in Europe 总被引:1,自引:0,他引:1
Christian Jaedicke Miet Van Den Eeckhaut Farrokh Nadim Javier Hervás Bjørn Kalsnes Bjørn Vidar Vangelsten Jessica T. Smith Veronica Tofani Roxana Ciurean Mike G. Winter Kjetil Sverdrup-Thygeson Egil Syre Helge Smebye 《Bulletin of Engineering Geology and the Environment》2014,73(2):325-339
Landslides are a serious problem for humans and infrastructure in many parts of Europe. Experts know to a certain degree which parts of the continent are most exposed to landslide hazard. Nevertheless, neither the geographical location of previous landslide events nor knowledge of locations with high landslide hazard necessarily point out the areas with highest landslide risk. In addition, landslides often occur unexpectedly and the decisions on where investments should be made to manage and mitigate future events are based on the need to demonstrate action and political will. The goal of this study was to undertake a uniform and objective analysis of landslide hazard and risk for Europe. Two independent models, an expert-based or heuristic and a statistical model (logistic regression), were developed to assess the landslide hazard. Both models are based on applying an appropriate combination of the parameters representing susceptibility factors (slope, lithology, soil moisture, vegetation cover and other- factors if available) and triggering factors (extreme precipitation and seismicity). The weights of different susceptibility and triggering factors are calibrated to the information available in landslide inventories and physical processes. The analysis is based on uniform gridded data for Europe with a pixel resolution of roughly 30 m × 30 m. A validation of the two hazard models by organizations in Scotland, Italy, and Romania showed good agreement for shallow landslides and rockfalls, but the hazard models fail to cover areas with slow moving landslides. In general, the results from the two models agree well pointing out the same countries with the highest total and relative area exposed to landslides. Landslide risk was quantified by counting the number of exposed people and exposed kilometers of roads and railways in each country. This process was repeated for both models. The results show the highest relative exposure to landslides in small alpine countries such as Lichtenstein. In terms of total values on a national level, Italy scores highest in both the extent of exposed area and the number for exposed population. Again, results agree between the two models, but differences between the models are higher for the risk than for the hazard results. The analysis gives a good overview of the landslide hazard and risk hotspots in Europe and allows a simple ranking of areas where mitigation measures might be most effective. 相似文献
996.
Comparison of thermal tolerance and standard metabolic rate of two Great Lakes invasive fish species
Ken G. Drouillard David A. Feary Xin Sun Jessica A. ONeil Todd Leadley Timothy B. Johnson 《Journal of Great Lakes research》2018,44(3):476-481
Round goby (Neogobius melanostomus) and western tubenose goby (Proterorhinus semilunaris) invaded the Laurentian Great Lakes at approximately the same time and area yet have shown substantial differences in their post-invasion success with more rapid establishment and development of much larger abundances of round goby populations throughout the invaded habitat. In this study, we compared differences in physiological performance (thermal tolerance and standard metabolic rate) between round and tubenose goby collected from the Huron-Erie corridor. Tubenose goby were observed to have lower thermal tolerance but exhibited similar standard metabolic rate across environmental temperatures compared to round goby. At temperatures exceeding 31 °C, tubenose goby demonstrated significantly higher mortalities and shorter times to death relative to round goby. The observed differences in thermal tolerance were consistent with differences in the native geographic ranges observed for each species at their southern ranges. The observed differences in physiological performance combined with species differences in other life history traits such body size, reproduction, feeding ecology and habitat affiliation may also explain differences in the invasiveness experienced by these two Great Lakes invasive fish including a greater ability of round gobies to occupy extreme habitats with large water temperature fluctuations. 相似文献
997.
Nysse-Carris Kari L.; Bottoms Bette L.; Salerno Jessica M. 《Canadian Metallurgical Quarterly》2011,17(1):76
We investigated adults' abilities to detect lies told by 3- to 6-year-old children. Expert forensic interviewers and novices watched videotapes of children who either lied or told the truth about their parent's transgression, rendered a dichotomous judgment of whether the child lied, rated their confidence in that judgment, and rated the children on various characteristics. Adults detected lies with greater than chance—but not impressive—accuracy, regardless of expertise level. Older children's lies were more detectable by experts than were younger children's. Adults were more confident in their judgments about older than younger children. Confidence in lie/truth judgments was not significantly correlated with actual lie detection accuracy. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
998.
Jessica A. Krogstad Rafael M. Leckie Stephan Krämer Julie M. Cairney Don M. Lipkin Curtis A. Johnson Carlos G. Levi 《Journal of the American Ceramic Society》2013,96(1):299-307
The correlation between microstructural and phase evolution in aged, yttria‐partially‐stabilized zirconia, air plasma‐sprayed coatings is discussed. Freestanding coatings with the dense, vertically cracked structure were isothermally aged at 1482°C (2700°F) in air. Characterization of the resulting microstructures was conducted using transmission electron microscopy, then compared with a parallel analysis of the phase evolution via synchrotron X‐ray diffraction (XRD) described in Part I. Additional context was provided by related studies on vapor‐deposited coatings. Several salient points can be extracted from these assessments. XRD was further validated as a practical method for studying phase stability after clarification of how the possible phases are defined, including the following: (i) the nature of the t′ phase observed in XRD after phase decomposition has begun and (ii) the relationship between the Y‐rich tetragonal (t″) and Y‐rich cubic (c) phases reported to coexist via XRD. A strong relationship between the initial microstructure and the subsequent phase destabilization is also reported. As a result, phase evolution is proposed to proceed via two competing routes. The interplay between these mechanisms dictates the incubation time for monoclinic formation within a given coating. 相似文献
999.
With the expansion of advanced metering and increased use of energy analytics tools, the energy efficiency community has begun to explore the application of advanced measurement and verification (or ‘M&V 2.0′) technologies. Current literature recognizes their promise, but does not offer in-depth assessment of technical underpinnings. This paper assesses the state of the technology and its application. Sixteen commercially available technologies were characterized and combined with a national review of their use. 相似文献
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