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Crisis communication is a field dominated by case studies and is lacking of systematic knowledge and theoretical framework analysis. Functionalist and objectivist perspectives have dominated the field even though there are exceptions. This may be one reason why multicultural approaches to crisis communication, increasingly relevant in contemporary society, are very few and undeveloped. The aim in the article is to give a critical analysis of research that has been done on crisis communication as well as intercultural public relations and develop a different theoretical framework. We propose the use of ethnicity, focusing collective cultural identity as dynamic, relational and situational in crisis theory and practice. Ethnic differences seem to escalate during crises. Media use and access are also discussed. A Swedish survey shows, among other things, that people with a foreign background read mainstream newspapers more seldom than average Swedes, but that the access to Internet and mobile phones is very high. Based on a social constructionist epistemology, the article ends with four proposals for future research and practice in multicultural crisis communication: (1) audience‐orientation – focusing sense‐making, (2) a proactive and interactive approach – focusing dialogue, (3) a community‐focused approach – focusing a long‐range pre‐crisis perspective and, (4) an ethnicity‐approach towards intercultural communication. 相似文献
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Thomas MacDougal Clunie Vladimir I. Nikora Stephen E. Coleman Heide Friedrich Bruce W. Melville 《Canadian Metallurgical Quarterly》2007,133(12):1345-1355
An innovative measurement system of “flying” acoustic Doppler velocimeters was designed in order to allow rapid velocity measurement over a large flow field. Such measurements are necessary, for example, when measuring over a temporally varying and locally nonuniform rough bed. The measurement technique was verified by comparison with measurements taken in the same flows using a traditional stationary probe technique. Comparison showed that the flying-probe approach performs similarly to stationary measurements in capturing the mean flow field and turbulent fluctuations. The data obtained from flying probe experiments can be used to describe the flow in terms of double-averaged hydrodynamic variables, obtained by averaging in time and spatial domains within a thin slab parallel to the mean bed. Examples are presented of flow measurements over a fixed flat bed, a fixed dune bed, and over mobile developing bed forms. It is shown that near-bed measurements suffer from boundary reflection interference, though affected data can be filtered out based on the ADV-measured correlation coefficient. Measurement below roughness tops is possible, with in-bed records being detectable by spikes in measured signal-to-noise-ratio and by comparison with measured bed topography. 相似文献
214.
Aluminium bronze, well known for its good sliding properties, is frequently applied as tool material in sheet metal forming (SMF) of stainless steel, e.g. for the production of washing, refrigeration and cooking equipment. The limited hardness of the material makes it, however, sensitive to tool wear that is: volumetric wear of the tool due to sliding contact with the sheet material. Conventional wear tests like the rubber wheel abrasion test or the Taber abrader test cannot be used to simulate the interaction of the tooling with lubricated sheet material. Dedicated tribo tests are therefore conducted with the slider-on-sheet test. The aim of the research is to measure the specific wear rate of aluminium bronze at SMF-like conditions. Experimental results showed a pronounced influence of lubricant selection and sheet material selection. The measured specific wear rate varied from 10−8 mm3/N m for a smooth stainless steel sheet quality to 10−6 mm3/N m for a rough surface quality. 相似文献
215.
Hedrich S Lünsdorf H Kleeberg R Heide G Seifert J Schlömann M 《Environmental science & technology》2011,45(18):7685-7692
Schwertmannite has previously been found in iron- and sulfate-rich mine waters at pH 2.8-4.5. In the present study, schwertmannite (Fe(8)O(8)(OH)(6)SO(4)) was shown to be the major mineral in a mine water treatment plant at pH 3, in which ferrous iron is mainly oxidized by bacteria belonging to the species Ferrovum myxofaciens. Strain EHS6, which is closely related to the type strain of Fv. myxofaciens, was isolated from the pilot plant and characterized as an acidophilic, iron-oxidizing bacterium. In contrast to the pilot plant, the mineral phase formed by a pure culture of Fv. myxofaciens EHS6 was a mixture of schwertmannite and jarosite (KFe(3)(SO(4))(2)(OH)(6)). In contrast to other reports of neutrophilic, iron-oxidizing bacteria, acidophilic microorganisms in the pilot plant and cultures of strain EHS6 did not show encrustation of the cell surface or deposition of minerals inside the cell, though a few cells appeared to be in contact with jarosite crystals. It was concluded that no direct biomineralization occurred in the pilot plant or in laboratory cultures. The lack of encrustation of bacterial cells in the pilot plant is considered advantageous since the cells are still able to get in contact with ferrous iron and the iron oxidation process in the mine water treatment plant can proceed. 相似文献
216.
Heide Humburg Eike Volkmann Dietmar Koch Jörg Müssig 《Journal of Materials Science》2014,49(23):8040-8050
The biological materials nacre and wood are renowned for their impressive combination of toughness and strength. The key mechanisms of these highly complex structures are crack deflection at weak interfaces, crack bridging, functional gradients and reinforcing elements. These principles were applied to a more fracture-tolerant model material which combined porous stiff ceramic layers, manufactured by freeze casting, infiltrated and bonded by a polymer phase reinforced with fabric layers. In the hybrid composites, crack deflection occurred at the ceramic–fabric interface and the intact fabric layers served as crack-bridging elements. Fabric-reinforced epoxy layers stabilized the fracture behaviour and delayed catastrophic failure of the material. The influence of the different components was analysed by varying the ceramic, fabric and interface properties. More ductile fabrics lead to larger strain to failure and more crack bridging but reduced the composite strength and stiffness after initial cracking. Higher elastic mismatch between the components improved crack deflection and bridging but resulted in deterred load transfer and a lower strength. The stiffness and strength of the ceramic layers influenced the elastic properties of the laminar composite and the initial crack resistance. Flaw tolerance was increased with polymer infiltration. We show with our hybrid ceramic–fabric composite as a bio-inspired concept study how fracture toughness, work of fracture and tolerance for cracking can be tailored when the contributing factors, i.e. the ceramic, the fabric and their interface, are modified. 相似文献
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Beate Brett Daniel Schrader Konstantin Räuchle Gerhard Heide Martin Bertau 《化学,工程师,技术》2015,87(10):1383-1391
The unexploited potential of ashes, especially from lignite combustion in power plants, for the strategic recovery of secondary resources requires a sufficient, substantial and reliable analysis. Thus, information facilitates pathways to dedicated metal extractions and optimized recovery strategies. Based on two fly ashes and a stabilized form, delivered from Lusatia, the characterization, concerning the particle size distribution, elemental and mineralogical composition and the ratio of network former to modifier, led to a significant increase in the mobilization of metals by the leaching of the educts with hydrochloric acid. 相似文献