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Gaze-controlled interfaces have become a viable alternative to hand-input-based displays and present a particular value to the field of assistive technologies, allowing people with motor disabilities to partake in activities that otherwise would have been inaccessible to them. The present paper gives an overview of the key problems associated with the user experience in gaze-controlled human–computer interfaces and introduces two areas of psychological research that could contribute to the development of gaze-controlled interfaces that give a more intuitive sense of control and are less likely to interfere with ongoing cognitive processes. Such interfaces are referred to as cognitively grounded. The two areas of psychological research that lead to the design of cognitively grounded gaze-controlled interfaces are the sense of agency and the cognitive embodiment. This overview builds on findings within these areas and outlines research questions essential to the design of cognitively grounded gaze-controlled interfaces.  相似文献   
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Abstract  

Alkylation of benzene with n-hexane was performed over H-ZSM-5 and monometallic Ga- and Pt- and bimetallic Ga- and Pt-modified ZSM-5. The influence of the particle size and the method of incorporation of Ga (during hydrothermal synthesis, by solid-state ion exchange, or by liquid-state ion exchange) was determined. The presence of Pt and well-dispersed extraframework Ga in H-ZSM-5 increased the selectivity in alkylation and suppressed cracking reactions. Well-dispersed Pt particles led to better catalytic performance. The method of Ga incorporation played an important role in obtaining higher selectivity to alkylation products and in the suppression of side reactions. Up to 93% selectivity in alkylation (of which >95% was to 2-phenylhexane) was reached over 2 wt% Pt/H-GafZSM5, in which Ga occupied framework positions. We propose that the close proximity of very small Pt nanoparticles and Ga–(OH)–Si acid sites results in the optimal bifunctional catalyst for selective production of 2-phenylhexane from benzene and n-hexane. During the reaction, the catalyst deactivated, most probably due to the sintering of the Pt particles.  相似文献   
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A new copolymer of N-[(tert-butylperoxy)methyl]acrylamide (tBPMAAm), containing a primary–tertiary peroxide group and maleic anhydride (MA), was synthesized and employed as a reactive surfactant (inisurf) for the emulsion polymerization of styrene to yield surface-functionalized (peroxidized) reactive latex particles. The copolymerization characteristics were analyzed to determine the monomer reactivity ratios and to provide a way to control the copolymer composition. The ability of tBPMAAm–MA to act as a reactive surfactant during emulsion polymerization was confirmed by the synthesis of monodisperse polystyrene latexes of varying particle size. In addition, peroxide groups were localized on the surface of the particles in a controllable amount (depending on the copolymer concentration), thus, providing the opportunity for further modification of the surface of the particles. This novel copolymer is expected to be a promising and efficient material in the synthesis of functional polymer nanoparticles with well-defined core–shell morphologies.  相似文献   
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An efficient way through borohydride synthesis route using NaBH4 was performed to prepare pure zirconia nanopowders via three different conditions such as gelation, precipitation, and constant pH. Zirconia powders prepared through constant pH route show highest activation energy of crystallization (Ea = 260 kJ/mol) or higher exothermic peak temperature (717°C), when compared with gelation or precipitation route due to its controlled growth of smaller crystallites. The released huge amount of H2 gas bubbles during borohydride synthesis via constant pH route play a major role for formation of loose smaller crystallites and thus enhances the activation energy of crystallization of pure zirconia. So, the as‐prepared zirconia powders prepared through constant pH route remain amorphous up to 600°C and pure t‐ZrO2 (~20 nm) was stable up to 800°C.  相似文献   
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In the present work, the influence of Cr and Ca co-additives on the phase formation under conditions emulated the real sintering process of Cr4+:YAG ceramics is studied. The XRD analysis of the treated samples revealed the difference in formation rates of intermediate phases between the samples with and without the Cr2O3 additive. The formation of intermediate phases in the solid-state reaction between Y2O3 and Al2O3 is observed to shift toward higher temperatures (ie, toward the stage of fast shrinkage) if the mixture of Cr2O3 and CaO is added. The reason for such shift is the appearance of new intermediate, which contains Cr4+ ions in perovskite structure, as has been established by optical absorption and luminescent investigations. It is found that the Cr,Ca:YAG ceramics prepared by vacuum solid state reaction sintering at 1750°C, 10 hours possesses better optical transparency than Ca:YAG ceramics prepared under the same conditions.  相似文献   
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Surface functionalization of magnetic particles is an elegant way to bridge the gap between heterogeneous and homogeneous catalysis. The introduction of magnetic particles (MPs) in a variety of solid matrices allows the combination of well‐known procedures for catalyst heterogenization with techniques for magnetic separation. We have conveniently loaded sulfonic acid groups on magnetic particles supports in which chlorosulfonic acid is used as sulfonating agent. The main targets are room temperature, solvent‐free conditions, rapid (immediately) and easy immobilization technique, and low cost precursors for the preparation of highly active and stable MPs with high densities of functional groups. The inorganic, magnetic, solid acid catalyst was characterized via Fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), thermal gravimetric analysis (TGA), X‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), dynamic light scattering (DLS), vibrating sample magnetometer (VSM) and titration. The catalyst is active for the Hantzsch reaction and the products are isolated in high to excellent yields (90–98%). Supporting this acid catalyst on magnetic particles offers a simple and non‐energy‐intensive method for recovery and reuse of the catalyst by applying an external magnet. Isolated catalysts were reused for new rounds of reactions without significant loss of their catalytic activity.  相似文献   
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The effect of titanium addition on the SAW weld metal microstructure of API 5L-X70 pipeline steel was investigated. The relationship between microstructure and toughness of the weld deposit was studied by means of full metallographic, longitudinal tensile, Charpy-V notch and HIC tests on the specimens cut transversely to the weld beads. The best combination of microstructure and impact properties was obtained in the range of 0.02–0.05% titanium. By further increasing of titanium content, the microstructure was changed from a mixture of acicular ferrite, grain-boundary ferrite and Widmanstätten ferrite to a mixture of acicular ferrite, grain-boundary ferrite, bainite and ferrite with M/A microconstituent. Therefore, the mode of fracture also changed from dimpled ductile to quasi-cleavage. The results showed an increase in the titanium content of inclusions with increased titanium levels of weld metal. Titanium-base inclusions improve impact toughness by increasing the formation of acicular ferrite in the microstructure. No HIC susceptibility was found in the weld metals with titanium contents less than 0.09%.  相似文献   
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