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951.
Lars Boeryd 《中国电子商情》2010,(6):20-21
正车载娱乐及导航系统领域正在经历着一些有趣的变化。客户更加依赖车载之外的移动设备,如手机、MP3、便携式游戏设备。人们更加希望这些设备可以在车载中进行无缝集成,甚至功能得到进一步强化。随着互联网的普及,人们也期望车载设备能够实现互联。娱乐和导航系统的设计者必须掌握这些趋势,并开发新的解决方案来满足这些需求。 相似文献
952.
Das Maule (Chile)‐Erdbeben vom 27. Februar 2010 gehört zu den stärksten, weltweit jemals registrierten Erdbeben. Das seismische Ereignis löste einen Tsunami aus, der durch mehrere Wellenfronten verheerende Schäden an der Küste Chiles verursachte. Ereignisspezifische Besonderheiten aus der überlagerung der Effekte aus Erdbeben und darauffolgenden Flutwellen (Tsunami) waren Motivation, im Rahmen einer Erkundungsmission der Ingenieurgruppe der Deutschen Task Force im betroffenen Gebiet die Bauwerksschäden aufzunehmen und ihre regionale Verteilung zu dokumentieren. Der Beitrag vermittelt einen Eindruck von den durch den Tsunami bedingten Schäden; es wird der Versuch unternommen, das Verhalten der typischen Bauweisen unter den zeitlich sequentiell auftretenden extremen Einwirkungen aufzuzeigen. Die Auswertungen schließen an die Ingenieuranalyse der Erdbebenschäden an, so dass auf die im vorangegangenen 1. Teil des Beitrags vom August 2010 [1] gegebene allgemeine übersicht zum Gebäudebestand in Chile und zur Typisierung der Bauweisen verwiesen werden kann. Die Schäden aus dem Tsunami konzentrieren sich auf die eher ländlichen und ohnehin weniger tauglichen traditionellen Bauweisen in den Küstenregionen. An den wesentlichen Wirkungsmechanismen eines Tsunami werden die Verletzbarkeit der Bauweisen und die Effizienz einfacher baulicher Schutzmaßnahmen herausgearbeitet. Wie gezeigt werden kann, tragen Schäden aus Treibgut erheblich zum Schadensbild bei. The Magnitude 8.8 Maule (Chile) earthquake of February 27, 2010 — Engineering analysis of tsunami damages. The Maule (Chile) February 27, 2010 earthquake is regarded as one of the strongest earthquakes ever recorded world‐wide. The seismic event triggered a tsunami which caused by several wave fronts serious damage alongside the coastal border. Event‐specific characteristics from the overlay of the effects from earthquakes and following flood wave (Tsunami) were motivation to examine building damage and to document their regional distribution, in the context of a reconnaissance mission of the engineering group of the German Task Force for earthquakes. The paper provides an impression from the tsunami induced damage to the different building types under the impact of time‐varying sequence of extreme natural events. First results of the studies in [1] are related to the engineering analysis of earthquake damage. Therefore it can be referred to the overview of the building stock and the predominant structural systems in Chile given there. Damage caused by the tsunami is concentrated on rural and often less resistant traditional buildings in coastal areas. The main loading and impact components induced by the tsunami are used to explain the vulnerability of building types and the efficiency of simple structural measures. As the damage cases demonstrate, debris in its general sense has contributed to the observed effects. 相似文献
953.
954.
Holck AL Axelsson L Rode TM Høy M Måge I Alvseike O L'abée-Lund TM Omer MK Granum PE Heir E 《Meat science》2011,89(3):286-295
After a number of foodborne outbreaks of verotoxigenic Escherichia coli involving fermented sausages, some countries have imposed regulations on sausage production. For example, the US Food Safety and Inspection Service requires a 5 log(10) reduction of E. coli in fermented products. Such regulations have led to a number of studies on the inactivation of E. coli in fermented sausages by changing processing and post-processing conditions. Several factors influence the survival of E. coli such as pre-treatment of the meat, amount of NaCl, nitrite and lactic acid, water activity, pH, choice of starter cultures and addition of antimicrobial compounds. Also process variables like fermentation temperature and storage time play important roles. Though a large variety of different production processes of sausages exist, generally the reduction of E. coli caused by production is in the range 1-2 log(10). In many cases this may not be enough to ensure microbial food safety. By optimising ingredients and process parameters it is possible to increase E. coli reduction to some extent, but in some cases still other post process treatments may be required. Such treatments may be storage at ambient temperatures, specific heat treatments, high pressure processing or irradiation. HACCP analyses have identified the quality of the raw materials, low temperature in the batter when preparing the sausages and a rapid pH drop during fermentation as critical control points in sausage production. This review summarises the literature on the reduction verotoxigenic E. coli in production of fermented sausages. 相似文献
955.
Kai Herbrig Lars Röntzsch Carsten Pohlmann Thomas Weißgärber Bernd Kieback 《International Journal of Hydrogen Energy》2013
The design of hydride-based hydrogen storage systems is non-trivial because numerous physical, chemical and engineering principles have to be considered. In particular, gas and heat transport properties of the hydride bed are crucial for a high-dynamic tank operation. Since most hydrides show low intrinsic heat conductivities, auxiliary materials or structures inside the reaction zone are beneficial. For that purpose, hydride–graphite composites with strong anisotropic thermal conductivities have been developed recently. 相似文献
956.
Cecilía Kristín Kjartansdóttir Lars Pleth Nielsen Per Møller 《International Journal of Hydrogen Energy》2013
A new type of electrodes for alkaline water electrolysis is produced by physical vapour depositing (PVD) of aluminium onto a nickel substrate. The PVD Al/Ni is heat-treated to facilitate alloy formation followed by a selective aluminium alkaline leaching. The obtained porous Ni surface is uniform and characterized by a unique interlayer adhesion, which is critical for industrial application. IR-compensated polarisation curves prepared in a half-cell setup with 1 M KOH electrolyte at room temperature reveals that at least 400 mV less potential is needed to decompose water into hydrogen and oxygen with the developed porous PVD Al/Ni electrodes as compared to solid nickel electrodes. High-resolution scanning electron microscope (HR-SEM) micrographs reveal Ni-electrode surfaces characterized by a large surface area with pores down to a few nanometre sizes. Durability tests were carried out in a commercially produced bipolar electrolyser stack. The developed electrodes showed stable behaviour under intermittent operation for over 9000 h indicating no serious deactivation in the density of active sites. 相似文献
957.
Do potential methylation rates reflect accumulated methyl mercury in contaminated sediments? 总被引:2,自引:0,他引:2
Relationships between the short-term mono-methyl mercury (MeHg) production, determined as the specific, potential methylation rate constant Km (day(-1)) after 48 h of incubation with isotope-enriched 201Hg(II) at 23 degrees C, and the long-term accumulation of ambient MeHg, were investigated in contaminated sediments. The sediments covered a range of environments from small freshwater lakes to large brackish water estuaries and differed with respect to source and concentration of Hg, salinity, primary productivity, quantity and quality of organic matter, and temperature climate. Significant (p < 0.001), positive relationships were observed between Km (day(-1)) and the concentration of MeHg normalized to total Hg (%MeHg) for surface sediments (0-10, 0-15, and in one case 0-20 cm) across all environments, and across subsets of organic and minerogenic freshwaters. This suggests that the methylation process (MeHg production) overruled demethylation and net transport processes in the surface sediments. The lack of a relationship between Km and %MeHg in two brackish water sediment depth profiles (0-100 cm) indicates that demethylation and the net effect of input-output are relatively more important at greater depths. Differences in the primary production and subsequent availability of easily degradable organic matter (serving as electron donor for methylating bacteria) was indicated to be the most important factor behind observed differences in %MeHg and Km among sites. In contrast, concentrations of sulfate were not correlated to Km, %MeHg, or absolute concentrations of MeHg. We conclude that total concentrations of Hg are of importance for the long-term accumulation of MeHg, and that %MeHg in surface sediments can be used as a proxy for the rate of methylation, across a range of sites from different environments. 相似文献
958.
Global emission and production of mercury during the pyrometallurgical extraction of nonferrous sulfide ores 总被引:1,自引:0,他引:1
The contribution of the milling, smelting, and refining of sulfide ores to Hg emissions and to Hg byproduction is not adequately quantified in a global context. In this study, we estimate Hg emissions from the pyrometallurgical treatment of Cu, Pb, and Zn sulfide ores. We base our calculations on quantities processed and Hg content in Cu, Pb, and Zn concentrates, derived from unique global databases on smelter feed and production. In 2005, about 275 tons of Hg were emitted globally to the atmosphere from Cu, Pb, and Zn smelters. Nearly one-half was emitted from Zn smelters and the other half equally divided between Cu and Pb smelters. Most Hg was emitted in China, followed by the Russian Federation, India, and South Korea. Global emission factors were 5.81, 15.71, and 12.09 g of Hg ton(-1) of metal for Cu, Pb, and Zn smelters, respectively. Calculations indicate that Hg abatementtechnologies applied to flue gases may have recovered 8.8 tons and 228 tons Hg from Pb and Zn smelters, respectively, most of which was probably sold as a byproduct. In conclusion, Hg emitted from processing copper, lead, and zinc ores has been largely underestimated in Hg emission inventories. Reducing these emissions may be one of the most economical measures to reduce global Hg emissions. 相似文献
959.
In recent years some research towards developing forecasting models for wind power or energy has been carried out. In order to evaluate the prediction ability of these models, the forecasts are usually compared with those of the persistence forecast model. As shown in this article, however, it is not reasonable to use the persistence model when the forecast length is more than a few hours. Instead, a new statistical reference for predicting wind power, which basically is a weighting between the persistence and the mean of the power, is proposed. This reference forecast model is adequate for all forecast lengths and, like the persistence model, requires only measured time series as input. Copyright © 1998 John Wiley & Sons, Ltd. 相似文献
960.
Jennifer Sun Lars G. Rudstam Brent T. Boscarino Maureen G. Walsh Brian F. Lantry 《Journal of Great Lakes research》2013
Hemimysis anomala is a warm-water mysid that invaded the Great Lakes region in 2006 and has since rapidly spread throughout the basin. We conducted three laboratory experiments to better define the temperature preference, tolerance limits, and temperature effects on feeding rates of juvenile Hemimysis, using individuals acclimated to mid (16 °C) and upper (22 °C) preferred temperature values previously reported for the species. For temperature preference, we fit a two-parameter Gaussian (μ, σ) function to the experimental data, and found that the peak values (μ, interpreted as the preference temperature) were 22.0 °C (SE 0.25) when acclimated to 16 and 21.9 °C (SE 0.38) when acclimated to 22 °C, with the σ-values of the curves at 2.6 and 2.5 °C, respectively. No mysids were observed in temperatures below 10 or above 28 °C in these preference experiments. In short-term tolerance experiments for temperatures between 4 and 32 °C, all mysids died within 8 h at 30.2 °C for 16 °C acclimated mysids, and at 31.8 °C for 22 °C acclimated mysids. No lower lethal limit was found. Feeding rates increased with temperature from an average of 4 Bosmina eaten per hour at 5 °C to 19 Bosmina eaten per hour at 27 °C. The results of our experiments indicate an optimal temperature for Hemimysis between 21 and 27 °C, which corresponds with temperatures during periods of high population growth in the field. These results contribute a better understanding of this species' biological response to temperature that will help guide field studies and inform bioenergetics modeling. 相似文献