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Joaquin  Jeremiah Joven  Tan  Raymond R. 《Scientometrics》2021,126(12):9633-9637
Scientometrics - Short communications are an integral part of academic journal publishing since they serve as a forum for scholarly debate on recently published journal articles. Their prestige and...  相似文献   
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In this work a new methodology based on thermo-pressing a resin made from gliadins and glycerol has been developed to obtain water resistant films. The effect of processing temperature was studied on the functional properties of the films. The results of SDS-PAGE analysis of the molecular weight profiles of the resulting films were indicative of disulfide/sulfhydryl interchange reactions giving rise to the formation of intermolecular disulfide bonds between the gliadin units. These reactions augmented the degree of cross-linking of the matrix, which increased with thermo-pressing temperature, as evidenced by the residual reaction enthalpy values determined by MDSC as well as by cross-linking density values determined from tensile tests. In consequence the films produced at high temperature had better water resistance upon immersion, greater maximum tensile strength and Young's modulus values, and lower water vapor and oxygen permeabilities compared with cast films. Based on the analytical test results, thermo-pressing the resin in successive time/force steps along with a temperature of 130 °C produced gliadin films with improved properties.  相似文献   
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Telecommunication Systems - The Software-Defined Networking (SDN) architecture decouples the control plane from the data plane, but it does not explicitly state where the control should be located....  相似文献   
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A new approach for multiantenna broadcast channels in cellular networks based on multiuser diversity concept is introduced. The technique called opportunistic interference management achieves dirty paper coding capacity asymptotically with minimum feedback required. When there are K antennas at the base station with M mobile users in the cell, the proposed technique only requires K integer numbers related to channel state information between mobile users and base station. The encoding and decoding complexity of this scheme is the same as that of point‐to‐point communications, which makes the implementation of this technique easy. An antenna selection scheme is proposed at the base station to reduce the minimum required mobile users significantly at the expense of reasonable increase in feedback. In order to guarantee fairness, a new algorithm is presented that incorporates opportunistic interference management into existing Global System for Mobile communications (GSM) standard. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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A simple strategy for the synthesis and functionalization of polyurethanes is described. Anionic ring‐opening polymerization was combined with ‘click’ chemistry to synthesize polyols with fluorescent properties. This route allows the incorporation of a wide range of functionalities in the polyols with an easy, clean and highly selective process compatible with several types of functional groups. The proposed strategy opens the way to the production, in a cost‐effective way, of ‘smart’ polyurethanes with non‐conventional properties like fire retardancy, antimite properties, antibacterial properties, etc. Alkynyl groups were introduced into the polyol chains by the controlled addition of glycidyl propargyl ether as co‐monomer during a conventional anionic ring‐opening copolymerization with propylene oxide. Subsequently 4‐azidomethyl‐7‐methoxycoumarin molecules were introduced onto the alkynyl‐polyether polyols by copper‐catalysed cycloaddition reactions to produce end‐functionalized polyols. The chemical structure of the novel polyols was characterized using infrared spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography with triple detection and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectroscopy. These characterization techniques confirmed the presence of a considerable amount of functional groups in the structure of the polyols. Finally, various fluorescent rigid foams, based on the functionalized polyols, were synthesized. Copyright © 2012 Society of Chemical Industry  相似文献   
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In the last years the amount of information being transmitted through communication networks has increased, and this has lead to an increased use of security protocols. The implementations of security protocols do not accurately follow the standards and this causes many malfunctions and security flaws. In this paper we will analyze the different approaches followed by the scientific community to evaluate security protocols' implementations, and will also analyze the special characteristics of security protocols, in order to deduce which are the key points for such an evaluation, how they can be evaluated and also if existing evaluation techniques can be used.  相似文献   
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The wetting of molten aluminum on the “c”-plane (0001) of single-crystal α-Al2O3 (sapphire) was studied by the sessile drop technique from 800 °C (1073 K) to 1200 °C (1473 K). Systematically increasing the (0001) surface roughness by SiC abrasion increased the wetting contact angle, resulting in reduced wetting. The surface roughness factor R originally defined by Wenzel, was determined as a function of the abrasion, temperature, and time. The wetting decreases as the surface roughness increases. Rough surfaces also create time and temperature effects on wetting, changing those for a smoothly polished surface. The existence of a high-temperature surface structural transition for (0001) of α-Al2O3, which has been previously suggested, was confirmed. Increased roughness R accents the effect of the surface structural transition, increasing the wetting contact angle changes during the transition.  相似文献   
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The effect of prereduction on CO oxidation activity of unsupported copper-chromite oxide catalysts was examined. Results were found to be in good agreement with two mechanisms for a surface copper enrichment due to CO prereduction which produced an activity increase in the copper-chromite catalyst.  相似文献   
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