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41.
The paper investigates a new technique to predict error rates in digital architectures based on microprocessors. Three studied cases are presented concerning three different processors. Two of them are included in the instruments of a satellite project. The actual space applications of these two instruments were implemented using the capabilities of a dedicated system. Results of the fault injection and radiation testing experiments and discussions about the potentialities of this technique are presented  相似文献   
42.
Isomerization of n-heptane over Ni-WO x /Al2O3-SiO2 catalysts was carried out in a continuous flow fixed-bed reactor under atmospheric pressure. The first part of this study deals with the preparation of two series of catalysts (A and B) by the sol-gel method, while the second part deals with the isomerization of n-heptane. The principal objective of this study was to choose the catalyst giving the best isomer yield (di- and tri-branched ones) with optimum reaction conditions (reaction temperature, reduction temperature and time on stream). From the results obtained, the optimum nickel content was found to be 15 wt% and it seems that the incorporation of tungsten (B series) leads to a significant enhancement in the activity of the prepared catalysts. After running on stream for 100 min, the catalyst with 15% nickel and 10% tungsten (B4 catalyst) gives the best results (29% conversion and 70% selectivity) at 250 °C.  相似文献   
43.
The paper provides a synthesis of the construction industry needs and requirements in relation to the adoption and use of information and communication technologies (ICT). This is based, on the one hand, on existing research and technology development initiatives commissioned at a national and European level, and, on the other, on a wide consultation with construction industry key players across Europe. A framework, used as a basis for capturing industry requirements, and formulating an ICT vision, has been defined. Five priority areas have been identified with the potential to solve the ICT related problems of the construction industry, namely: knowledge management, legal and contractual aspects management, quality and performance management, total lifecycle management, and human aspects management. The ICT vision, enabled by addressing these priority areas, has been formulated on a consensus basis, and a detailed roadmap has been developed providing a pragmatic implementation of the proposed vision.  相似文献   
44.
Poly(lactic acid)/2 wt % organomodified montmorillonite (PLA/OMMT) was toughened by an ethylene‐methyl acrylate‐glycidyl methacrylate (E‐MA‐GMA) rubber. The ternary nanocomposites were prepared by melt compounding in a twin screw extruder using four different addition protocols of the components of the nanocomposite and varying the rubber content in the range of 5–20 wt %. It was found that both clay dispersion and morphology were influenced by the blending method as detected by X‐ray diffraction (XRD) and observed by TEM and scanning electron microscopy (SEM). The XRD results, which were also confirmed by TEM observations, demonstrated that the OMMT dispersed better in PLA than in E‐MA‐GMA. All formulations exhibited intercalated/partially exfoliated structure with the best clay dispersion achieved when the clay was first mixed with PLA before the rubber was added. According to SEM, the blends were immiscible and exhibited fine dispersion of the rubber in the PLA with differences in the mean particle sizes that depended on the addition order. Balanced stiffness‐toughness was observed at 10 wt % rubber content in the compounds without significant sacrifice of the strength. High impact toughness was attained when PLA was first mixed with the clay before the rubber was added, and the highest tensile toughness was obtained when PLA was first compounded with the rubber, and then clay was incorporated into the mixture. Thermal characterization by DSC confirmed the immiscibility of the blends, but in general, the thermal parameters and the degree of crystallinity of the PLA were not affected by the preparation procedure. Both the clay and the rubber decreased the crystallization temperature of the PLA by acting as nucleating agents. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41518.  相似文献   
45.
With the new regulations and policies related to climate change, the construction industry has been put under pressure to increase the sustainability of its practices. Many organisations are now adapting their practices to meet government legislative targets (e.g. reducing carbon emissions) and consider the environmental, social and economic performance of buildings. In addition, the sustainable construction is also a rapidly changing field, with technological advances, changes in legislation and increasingly educated clients driving the industry to constantly adapt to remain competitive. This represents a key problem for construction professionals as they must continually be aware of new information, best practices, technologies and changing legislation (at a local, national and international level) which are often disseminated from different organisations/individuals through dispersed media.  相似文献   
46.
Candesartan is an angiotensin receptor blocker (ARB) used to treat hypertension. However, its poor aqueous solubility and oral bioavailability have limited its therapeutic applications. In order to increase bioavailability and control the release of candesartan condensation, microspheres containing biodegradable polymers (polyvinylpyrrolidone [PVP K30] and polylactic acid [PLA]) in different ratios were prepared by the o/o solvent evaporation method using Span 80 as a surfactant. In addition, the impact of encapsulation parameters (i.e., PVP K30 and PLA concentrations) on the encapsulation ratio and release percentage was investigated by the mixed factorial design method. The release kinetics of the microspheres was simulated by combining two methods, the Dragonfly algorithm and a support vector machine (DA-SVM). The experimental data were in good agreement with the predicted data, with a coefficient of determination close to unity and a mean square error close to zero. Fourier-transfer infrared spectrometry (FTIR) analysis revealed the presence of condensation in all formulations without reporting distortion in the spectra. Scanning electron microscopy (SEM) confirmed the successful synthesis of microspheres, whose sizes were between 12 and 26 μm. Formulations with a PLA-drug ratio of 6:1 (N15, N17, and N18) showed the highest encapsulation efficiency (68%, 71%, and 70%, respectively), while formulations that do contain PVP K30, such as N5, N4, and N3, showed a higher release (83%, 84%, and 89%, respectively), indicating that the agent (PVP K30) enhanced the bioavailability and release of candesartan. Overall, N3 showed a higher drug release rate at 12 h and important encapsulation efficiency, making it the optimal formulation obtained in this study.  相似文献   
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