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141.
Bernd Propfe Danny Kreyenberg Joerg Wind Stephan Schmid 《International Journal of Hydrogen Energy》2013
There is currently intensive public discussion of fuel cell electric vehicles (FCEV) and other electric powertrains, such as battery electric vehicles (BEV), plug-in hybrid electric vehicles (PHEV) and hybridized combustion engine vehicles (HEV). In this context, the German government has set the target of one million electric vehicles on the road by 2020, and six million by 2030 [1]. The goal of this paper is to identify the possible market share of electric vehicles in the German new car fleet in three scenarios in the timeframe from 2010 to 2030. The VECTOR21 vehicle technology scenario model is used to model the fleet in three scenarios. In the reference scenario with business-as-usual parameters, 189,000 electric vehicles will be sold in Germany by 2020. Scenario two with purchase price incentives from 5000 EUR, high oil prices, and low prices for hydrogen and electricity will result in 727,000 vehicles. In the last scenario with substantial OEM mark-up reductions and external conditions as in the business-as-usual scenario, 3.28 million vehicles will be sold. 相似文献
142.
The spectacular recent economic growth in the Asia-Pacific region in general, and in many of the economies of Northeast Asia in particular, has spurred a vast expansion in the need for energy services, and an expansion in the demand for the fuels that help to supply these services. Future projections suggest that the growth of fossil fuel use in Northeast Asia, especially in China, will have major consequences for financial and fuel markets and pollution both regionally and globally. Before the project described in this paper was initiated, there was no ongoing forum for energy experts from all of the countries of the region to meet, informally and in an unofficial capacity, to discuss openly and in a targeted fashion the energy situations in their countries, and to work together to evaluate the energy efficiency costs and benefits of different ways of meeting regional demand. The Asian Energy Security (AES) project provides such a forum, and as such constitutes a unique resource in the engagement of the countries of Northeast Asia on the topic of energy security. 相似文献
143.
Oxidation of antibacterial molecules by aqueous ozone: moiety-specific reaction kinetics and application to ozone-based wastewater treatment 总被引:2,自引:0,他引:2
Ozone and hydroxyl radical (*OH) reaction kinetics were measured for 14 antibacterial compounds from nine structural families, to determine whether municipal wastewater ozonation is likely to result in selective oxidation of these compounds' biochemically essential moieties. Each substrate is oxidized by ozone with an apparent second-order rate constant, k'(O3,app) > 1 x 10(3) M(-1) s(-1), at pH 7, with the exception of N(4)-acetylsulfamethoxazole (K'(O3,app) is 2.5 x 102 M(-1) s(-1)). k'(O3,app) values (pH 7) for macrolides, sulfamethoxazole, trimethoprim, tetracycline, vancomycin, and amikacin appear to correspond directly to oxidation of biochemically essential moieties. Initial reactions of ozone with N(4)-acetylsulfamethoxazole, fluoroquinolones, lincomycin, and beta-lactams do not lead to appreciable oxidation of biochemically essential moieties. However, ozone oxidizes these moieties within fluoroquinolones and lincomycin via slower reactions. Measured k'(O3,app) values and second-order *OH rate constants, k'(*OH,app) were utilized to characterize pollutant losses during ozonation of secondary municipal wastewater effluent. These losses were dependent on k'(O3,app), but independent of k'(*OH,app). Ozone doses > or =3 mg/L yielded > or =99% depletion of fast-reacting substrates (K'(O3,app) > 5 x 10(4) M(-1) s(-1)) at pH 7.7. Ten substrates reacted predominantly with ozone; only four were oxidized predominantly by .OH. These results indicate that many antibacterial compounds will be oxidized in wastewater via moiety-specific reactions with ozone. 相似文献
144.
Kinetics and mechanistic aspects of As(III) oxidation by aqueous chlorine, chloramines, and ozone: relevance to drinking water treatment 总被引:1,自引:0,他引:1
Dodd MC Vu ND Ammann A Le VC Kissner R Pham HV Cao TH Berg M Von Gunten U 《Environmental science & technology》2006,40(10):3285-3292
Kinetics and mechanisms of As(III) oxidation by free available chlorine (FAC-the sum of HOCl and OCl-), ozone (O3), and monochloramine (NH2Cl) were investigated in buffered reagent solutions. Each reaction was found to be first order in oxidant and in As(III), with 1:1 stoichiometry. FAC-As(III) and O3-As(III) reactions were extremely fast, with pH-dependent, apparent second-order rate constants, k'app, of 2.6 (+/- 0.1) x 10(5) M(-1) s(-1) and 1.5 (+/- 0.1) x 10(6) M(-1) s(-1) at pH 7, whereas the NH2Cl-As(III) reaction was relatively slow (k'app = 4.3 (+/- 1.7) x 10(-1) M(-1) s(-1) at pH 7). Experiments conducted in real water samples spiked with 50 microg/L As(III) (6.7 x 10(-7) M) showed that a 0.1 mg/L Cl2 (1.4 x 10-6 M) dose as FAC was sufficient to achieve depletion of As(III) to <1 microg/L As(III) within 10 s of oxidant addition to waters containing negligible NH3 concentrations and DOC concentrations <2 mg-C/L. Even in a water containing 1 mg-N/L (7.1 x 10(-5) M) as NH3, >75% As(III) oxidation could be achieved within 10 s of dosing 1-2 mg/L Cl2 (1.4-2.8 x 10(-5) M) as FAC. As(III) residuals remaining in NH3-containing waters 10 s after dosing FAC were slowly oxidized (t1/2 > or = 4 h) in the presence of NH2Cl formed by the FAC-NH3 reaction. Ozonation was sufficient to yield >99% depletion of 50 microg/L As(III) within 10 s of dosing 0.25 mg/L O3 (5.2 x 10(-6) M) to real waters containing <2 mg-C/L of DOC, while 0.8 mg/L O3 (1.7 x 10(-5) M) was sufficientfor a water containing 5.4 mg-C/L of DOC. NH3 had negligible effect on the efficiency of As(III) oxidation by O3, due to the slow kinetics of the O3-NH3 reaction at circumneutral pH. Time-resolved measurements of As(III) loss during chlorination and ozonation of real waters were accurately modeled using the rate constants determined in this investigation. 相似文献
145.
Hermanns JF Piérard-Franchimont C Piérard GE 《International journal of cosmetic science》2000,22(1):67-71
Synopsis
Few subjects are as problematical to dermatologists, cosmetologists and related experimenters involved in safety testing as the clinical assessment of skin colour. At the core of the problem is the word erythema, which does not communicate a sense for the nuance of red. In addition, light shades of red are not visible in dark-skinned people. Human assays aiming at evaluating the irritancy and allergic potential of cosmetics take advantage to use instrumental assessments of skin colour. However, there are pitfalls related to the complex biological aspects of the cutaneous reactivity, to the design of the in vivo assay, and to technical aspects bound to the principle of the measuring methods. Sound information can only be reached when these concerns are solved.
Résumé
Peu de sujets sont aussi problématiques pour les dermatologues, cosmétologues et autres expérimentateurs impliqués dans les tests de sûreté que l'évaluation clinique des couleurs cutanées. Au centre du problème est le mot érythème qui ne communique pas la notion des nuances de rouge. De plus, un érythème discret peut ne pas être visible chez des individus à la peau foncée. Les tests humains visant àévaluer les potentialités d'irritation et d'allergie aux cosmétiques bénéficient des évaluations instrumentales de la couleur cutanée. Cependant, il existe des pièges liés aux aspects biologiques complexes de la réactivité cutanée, au choix du test in vivo et à des aspects techniques en relation avec le principe du système de mesure. Une information adéquate ne peut être obtenue qu'après avoir résolu ces problèmes. 相似文献
Few subjects are as problematical to dermatologists, cosmetologists and related experimenters involved in safety testing as the clinical assessment of skin colour. At the core of the problem is the word erythema, which does not communicate a sense for the nuance of red. In addition, light shades of red are not visible in dark-skinned people. Human assays aiming at evaluating the irritancy and allergic potential of cosmetics take advantage to use instrumental assessments of skin colour. However, there are pitfalls related to the complex biological aspects of the cutaneous reactivity, to the design of the in vivo assay, and to technical aspects bound to the principle of the measuring methods. Sound information can only be reached when these concerns are solved.
Résumé
Peu de sujets sont aussi problématiques pour les dermatologues, cosmétologues et autres expérimentateurs impliqués dans les tests de sûreté que l'évaluation clinique des couleurs cutanées. Au centre du problème est le mot érythème qui ne communique pas la notion des nuances de rouge. De plus, un érythème discret peut ne pas être visible chez des individus à la peau foncée. Les tests humains visant àévaluer les potentialités d'irritation et d'allergie aux cosmétiques bénéficient des évaluations instrumentales de la couleur cutanée. Cependant, il existe des pièges liés aux aspects biologiques complexes de la réactivité cutanée, au choix du test in vivo et à des aspects techniques en relation avec le principe du système de mesure. Une information adéquate ne peut être obtenue qu'après avoir résolu ces problèmes. 相似文献
146.
147.
148.
Wolter Marc Tedjo-Palczynski Irene Hentschel Bernd Kuhlen Torsten 《Computer Graphics and Applications, IEEE》2009,29(6):54-64
Scientific-visualization tools can make time-varying simulations easier to understand. The growing efficiency of today's high-performance computers enables simulation of physical phenomena with a high temporal resolution. Consequently, visualization systems require efficient navigation in the temporal dimension. This 3D user interface employs direct-manipulation metaphors for temporal navigation in scientific visualizations. By interacting with objects using their 3D trajectory, users can navigate in time by specifying spatial inputs. This article is part of a special issue on 3D user interfaces. 相似文献
149.
Chiara Uboldi Daniele Bonacchi Giada Lorenzi M Iris Hermanns Christine Pohl Giovanni Baldi Ronald E Unger C James Kirkpatrick 《Particle and fibre toxicology》2009,6(1):18-12
Background
During the last years engineered nanoparticles (NPs) have been extensively used in different technologies and consequently many questions have arisen about the risk and the impact on human health following exposure to nanoparticles. Nevertheless, at present knowledge about the cytotoxicity induced by NPs is still largely incomplete. In this context, we have investigated the cytotoxicity induced by gold nanoparticles (AuNPs), which differed in size and purification grade (presence or absence of sodium citrate residues on the particle surface) in vitro, in the human alveolar type-II (ATII)-like cell lines A549 and NCIH441. 相似文献150.
Rainer Dudek Ralf Doering Christine Bombach Bernd Michel 《Microelectronics Reliability》2009,49(8):839-845
Secondary effects on thermal fatigue of solder joints, which frequently have been neglected, were studied by means of the finite element method (FEM). Based on a semi-empirical approach to predict fatigue life by evaluating the cyclic accumulated equivalent creep strain or energy density, effects of organic boards intrinsic properties on solder joint fatigue were investigated. Aspects of more realistic FR-4 board modelling were studied, in particular concerning its in-plane anisotropy and intrinsic warpage behaviour. Intrinsic board warpage was measured on test board level as well as for boards from series production. High intrinsic warpage was in particular found for several test boards. The effects for the worst case scenario observed so far were analysed for both first level and second level interconnects. The change in predicted fatigue life varied between 30% and 500%, the latter most critical effects were found at large QFN components. Another secondary effect studied was to include the frequently neglected interfacial intermetallics into FEM. It turned out that for components with relatively large standoff like LFBGAs the effects were actually negligible, but for the highly miniaturized components like chip resistors CR0201 they are the decisive factor. 相似文献