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71.
Sona Chavoshizadeh Sajad Pirsa Forough Mohtarami 《European Journal of Lipid Science and Technology》2020,122(3)
In this study, a smart biodegradable film based on wheat gluten modified with chlorophyll (WG/Ch) is presented. The effect of chlorophyll on the antioxidant activity and mechanical properties of WG/Ch film is studied. Scanning electron microscopy and Fourier‐transform infrared spectroscopy (FT‐IR) analyses are used to study the structure and chemical composition of gluten‐based films. The WG/Ch film is used in the packaging of sesame oil. The effect of WG/Ch film on increasing the shelf life and detecting expiration time of oil is studied. FT‐IR results show that weak interactions are created between gluten and chlorophyll. The antioxidant activity of the WG film is 60% and it increases to 85% by the addition of chlorophyll. The results show that with the increasing storage time of oil samples, oxidative indices are increased, but the WG/Ch film decreases the sesame oil oxidation significantly (almost in the all oxidative indices 50% decrease is observed). Practical Applications: The WG/Ch film is used in the packaging of sesame oil. The effect of WG/Ch film on the increasing of shelf life and detecting expiration time of oil is studied. By increasing storage time and oxidant, acidity, acid number, PA, and oil color change are increased, but the WG/Ch active film decreases the sesame oil oxidation significantly. Also, by examining the color properties of the active film, it is observed that with increasing storage time and oxidant percent, the color of the film is changed (from green to yellow), which can be used to estimate the oil expiration time. It should be mentioned that the film's color changes are visible to the naked eye. 相似文献
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Mrunali Sona K. N. Prabhu 《Journal of Materials Science: Materials in Electronics》2013,24(9):3149-3169
The use of Pb-bearing solders in electronic assemblies is avoided in many countries due to the inherent toxicity and environmental risks associated with lead. Although a number of “Pb-free” alloys have been invented, none of them meet all the standards generally satisfied by a conventional Pb–Sn alloy. A large number of reliability problems still exist with lead free solder joints. Solder joint reliability depends on mechanical strength, fatigue resistance, hardness, coefficient of thermal expansion which are influenced by the microstructure, type and morphology of inter metallic compounds (IMC). In recent years, Sn rich solders have been considered as suitable replacement for Pb bearing solders. The objective of this review is to study the evolution of microstructural phases in commonly used lead free xSn–yAg–zCu solders and the various factors such as substrate, minor alloying, mechanical and thermo-mechanical strains which affect the microstructure. A complete understanding of the mechanisms that determine the formation and growth of interfacial IMCs is essential for developing solder joints with high reliability. The data available in the open literature have been reviewed and discussed. 相似文献
76.
Vitturi S. Carreras I. Miorandi D. Schenato L. Sona A. 《Industrial Informatics, IEEE Transactions on》2007,3(4):275-288
Several recent studies have addressed the suitability of current wireless technologies for industrial communications which, frequently, are requested to cope with severe timing constraints. Most of the analysis that have lately appeared in the literature have focused on the performance offered by the lower layers of the communication stack. However, in order to obtain a complete picture, it is important to analyze how this gets coupled with the features of higher layer protocols typically employed by industrial communication applications. In this paper, we investigate the performance obtained by an application layer protocol, derived from those currently employed by wired fieldbuses, running over COTS devices based on two popular wireless communication standards, namely, IEEE 802.15.4 and IEEE 802.11. In particular, we present a mapping of the application service elements onto the services offered by the mentioned wireless systems and discuss some possible design choices. A prototype of the application layer protocol is then implemented for each considered wireless technology and the performance figures evaluated by means of experimental measurements. 相似文献
77.
Methyl tert-butylether (MTBE) used as fuel oxygenate poses problems for water suppliers since it is persistent in the aquatic environment and the removal efficiency by conventional water treatment methods (aeration or activated carbon filtration) is rather low. Substitution by other ether compounds such as ethyl tert-butylether (ETBE), tert-amylmethylether (TAME) or di-isopropylether (DIPE) is discussed, however, their environmental behaviour is similar to that of MTBE. Experiments investigating the elimination efficiency of AOP were carried out in tap water and water from Lake Constance. The elimination efficiency for all treatment processes was found to follow the order: MTBE < TAME approximately equal ETBE < DIPE For all compounds under investigation, neither pure ozonation nor UV irradiation yield a considerable concentration decline. Only the formation of highly reactive OH radicals shows a potential for removing the ethers from water. Therefore the addition of H2O2 in equimolar ratio prior to ozone admixing proved to be quite efficient. The application of combined UV/H2O2 showed good results in all cases; the best concentration decline was achieved with UV/ozone. The rate of elimination of the three substitutes for MTBE (ETBE, TAME and DIPE) is higher in all processes; nevertheless, no complete removal could be achieved. Therefore, from the point of view of water suppliers, the use of other ethers as substitute for MTBE is posing the same problems as MTBE. 相似文献
78.
This paper propose a first approach to deal with contextual information in structured domains by recursive neural networks. The proposed model, i.e., contextual recursive cascade correlation (CRCC), a generalization of the recursive cascade correlation (RCC) model, is able to partially remove the causality assumption by exploiting contextual information stored in frozen units. We formally characterize the properties of CRCC showing that it is able to compute contextual transductions and also some causal supersource transductions that RCC cannot compute. Experimental results on controlled sequences and on a real-world task involving chemical structures confirm the computational limitations of RCC, while assessing the efficiency and efficacy of CRCC in dealing both with pure causal and contextual prediction tasks. Moreover, results obtained for the real-world task show the superiority of the proposed approach versus RCC when exploring a task for which it is not known whether the structural causality assumption holds. 相似文献
79.
Bertocco M. Farias M. Fortin D. Sona A. 《IEEE transactions on instrumentation and measurement》2008,57(7):1304-1312
This paper deals with cross-layer measurements for the efficient analysis of Digital Video Broadcasting-Terrestrial (DVB-T) system performance. In particular, valuable relationships between some cross-layer DVB-T system parameters are investigated through measurements conducted at the physical and application layers. Specifically, channel power, error vector magnitude, and modulation error ratio are assessed at the physical layer, whereas objective video quality indices are estimated at the application layer. To this aim, a number of real-life experiments are executed through a purposely developed testbed that enlists a suitable DVB-T transmission platform and real-life receivers. The ultimate goal is to highlight the importance of cross-layer measurements in the analysis and troubleshooting of DVB-T system operation and to show how to deduce from such measurements practical information and hints to be profitably used in the design and setup of any DVB-T broadcasting system. 相似文献