Fault arcs effects in cable bundles for space applications invacuum

A multitude of `arc tracking' tests on cables for space applications has been performed to improve the basic understanding of the phenomena responsible for the fault arc behavior. The damage in a cable bundle develops in a complex system consisting of metallic conductors, insulation materials and arc plasma. Considering the degradation effects, vacuum as one of the applied test parameters, has turned out to be an important test environment. The investigations are based on a new test method, developed to assess arc tracking properties of cables for space applications. Tests were conducted with different insulation materials at cables with different AWG at 125 V dc and nominal currents. The tests were focused on the vacuum environment, using air only for the purpose of comparison. For some cable types, vacuum has turned out to be a worst-case environmental condition with respect to fault arc effects, such as the conductor burn-off, degradation of the insulation of adjacent cables and the extension of the fault arc. This paper presents these worst case experiments in detail     

Investigation of Functional Hemispheric Asymmetry of Language in Tinnitus Sufferers.

The authors tested functional hemispheric asymmetry through word dichotic listening and lateralized lexical decision tasks in tinnitus patients and controls stimulated by a continuous tinnitus-like noise to test the influence of a tinnitus-like external stimulation. A classic right-ear advantage was shown in the auditory task for all but right-ear tinnitus patients, who performed as equally badly when the stimuli were presented to the right and left ears. Concerning the visual task, all participants demonstrated the expected right visual field advantage for word stimuli. Moreover, those who submitted to external stimulation demonstrated normal asymmetric patterns. These data suggest a specific effect of tinnitus on central processing and provide evidence for a functional reorganization induced by this auditory phantom perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Silicon-29 solid-state nuclear magnetic resonance spectroscopy of composite interfaces

The types of structures and bonds that are formed with silicons in the composite interface were studied using ²⁹Si cross-polarization/magic angle sample spinning (CP/MAS) nuclear magnetic resonance spectroscopy (NMR). The change in mobility of silane coupling agent bonded to silica, as compared with bulk hydrolyzed silane coupling agent, can be monitored by the change in line width and the shift of resonances to higher fields, as well as by the change in the silicon-proton cross-polarization time T_SiH. In the silane coupling agent-matrix resin interface, the T_SiH values reflect the change in mobility as a function of the concentration and degree of hydrolysis of the silane coupling agent. It has been demonstrated that quantitative measurements of T_SiH can be used to investigate relative mobilities.     

Comparison of primary and secondary aminosilance coupling agents in anhuydride-curde epoxy fiberglass composites

Fourier transform infrared spectroscopy (FT-IR) has been utilized to investigate the interfacial chemical bonding at the interfaces of the aminosilanes and the nedic methyl anhydiride cured epoxy matrix in fiber-reinforced composites. It is found that the nedic methyl anhydride can react with γ-aminopropyltriethoxysilane (APS) and N-methylaminoproplytrimethoxysilane (MAPS). In comparing the relative reactivities of two coupling agents to the epoxy resin, the secondary aminosilance has a higher reactivity than the primary aminosilance. An elevated temperature is required for the copolymerization to take place between the silane and the epoxy resin. The results indicate that covalent bonds form at the coupling agents. The molecular structure of the interface in MAPS treated fiberglass reinforced composites is different from that of the APS treated fiber composites. In addition, an accelerated copolymerization initiated by the coupling agent treated surface is also found in the resin interphase which may be important in determining the mechanical properties of the composites.     

Chemical reactions occurring at the interface of epoxy matrix and aminosilane coupling agents in fiber-reinforced composites

The chemical reactions at the interface between an anhydride-cured epoxy resin and an aminosilane treated fiber have been investigated using Fourier transform infrared methods (FT-IR). The results indicate that chemical bonds are formed in the interfacial region between the matrix and the coupling agents. The amount of interfacial bonding depends on the composition and the processing conditions.     

南京钢铁联合有限公司应用清洁生产技术提高余热余压综合利用效率

清洁生产是指不断采取改进设计、使用清洁的能源和原料、采用先进的工艺技术与设备、改善管理、综合利用等措施,从源头削减污染,提高资源（含能源）利用效率,减少或者避免生产、服务和产品使用过程中污染物的产生和排放。以减轻或者消除对人类健康和环境的危害。我国先后颁布了“中华人民共和国清洁生产促进法”和“清洁生产审核暂行办法”等法律法规。鼓励和促进清洁生产,以实现节能、降耗、减污、增效。为宣传在实施清洁生产过程中取得的成功经验,我刊将陆续刊登清洁生产实施案例以飨读者。同时欢迎您积极参与![编者按]     

Caffeine intake and its sources: A review of national representative studies

Aim of this review is to summarize current daily caffeine intake of children, adolescents, and adults, and trends in caffeine intake over the past decade. A literature search was conducted (1997–2015) which yielded 18 reports on nationally representative studies, describing caffeine consumption of over 275,000 children, adolescents and adults. The data revealed that mean total daily caffeine intake in children, adolescents, and adults is below caffeine intake recommendations such as those stated by Health Canada (2.5 mg/kg bw/day for children and adolescents, and 400 mg/day for adults) and the European Food Safety Authority, EFSA (3 mg/kg bw/day for children and adolescents, and 400 mg/day for adults). Total daily caffeine intake has remained stable in the last 10–15 years, and coffee, tea and soft drinks are the most important caffeine sources. Across all age groups, energy drinks contribute little to total caffeine intake. The highest potential for reducing daily caffeine intake is by limiting coffee consumption, and in some countries and age groups, by reducing tea and soft drink consumption.     

Electrochemical performance and modeling of lithium‐sulfur batteries with varying carbon to sulfur ratios

Lithium‐sulfur batteries have attracted much research interest because of their high theoretical energy density and low‐cost raw materials. While the electrodes are composed of readily available materials, the processes that occur within the cell are complex, and the electrochemical performance of these batteries is very sensitive to a number of cell processing parameters. Herein, a simple electrochemical model will be used to predict, with quantitative agreement, the electrochemical properties of lithium‐sulfur cathodes with varying carbon to sulfur ratios. The discharge capacity and the polarization were very similar for the lowest sulfur loadings, while above 23.2 wt% sulfur the gravimetric capacity dropped significantly, and there was an increase in the cell polarization. In addition, a transition in the electrode morphology, from well dispersed to aggregated sulfur at the surface, will be reflected in the change in a critical model parameter demonstrating the sensitivity and functionality of even this simple model in predicting complex behavior in the lithium‐sulfur cells.