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排序方式: 共有1109条查询结果,搜索用时 31 毫秒
51.
52.
Since the introduction of the energy label for household dishwashers in the EU, manufacturers have been incentivised to reduce resource consumption and increase the energy efficiency of their appliances. Technological progress has led to very efficient programmes with cleaning cycles of 3 to 4 h or longer. The European Commission recently initiated a revision of the energy label and Ecodesign requirements, leading to their adjustment to the state of the art and to actual usage patterns. The University of Bonn was tasked with investigating dishwashing habits in Europe. An online survey was conducted in 11 countries of the EU with more than 5000 participants. The survey focused on the choice of programme, attitudes towards energy-saving programmes and practices and the willingness to apply them. It appears that consumers are willing to apply energy-saving practices and to use energy-saving programmes, but the acceptance of long cycles that take more than 2 h is low, which stands in contradiction to the fact that 19% of all dishwashing cycles are run in the Eco programme, which takes more than 2 h in most cases. The percentage of people who understand that long cycles can be energy-efficient is smaller than the percentage of those who do not believe this. The statements of the participants are contradictory regarding the importance of saving energy and of programme duration. The results of the survey point out the importance of better consumer education and better communication by manufacturers, consumer organisations and legislation. 相似文献
53.
Samples of (Cu46Zr46Al8)100?xZx metallic glass forming alloys with diameters 2–6 mm were prepared by injection casting. The effect of minor amounts of elements Z = Gd, Co and Re with positive enthalpy of mixing within the Gd–Zr, Cu–Co and Cu–Re terminal systems was compared. The addition of Gd up to x = 2 slightly enhances the glass forming ability, Co reduces the critical diameter of bulk metallic glass formation, whereas even for small fractions of Re bulk samples were crystalline, but only amorphous splats can be prepared. Both Gd and Co diminish the crystallization temperature Tx with respect to the Cu46Zr46Al8 master alloy, but in Re-bearing splats Tx is increased. Alloying with optimum amounts of Gd and Co up to x = 2 leads to plastic deformability of rods, 2 and 3 mm in diameter, in comparison with the brittle Cu46Zr46Al8 bulk metallic glass. 相似文献
54.
Electrochemical characterization of electrolytes for lithium-ion batteries based on lithium difluoromono(oxalato)borate 总被引:1,自引:0,他引:1
Sandra ZugmannDominik Moosbauer Marius AmerellerChristian Schreiner Franz WudyRené Schmitz Raphael SchmitzPhilipp Isken Christian DippelRomek Müller Miriam KunzeAlexandra Lex-Balducci Martin WinterHeiner Jakob Gores 《Journal of power sources》2011,196(3):1417-1424
The salt lithium difluoromono(oxalato)borate (LiDFOB) showed some promising results for lithium-ion-cells. It was synthesized via a new synthetic route that avoids chloride impurities. Here we report the properties of its solutions (solvent blend ethylene carbonate/diethyl carbonate (3:7, mass ratio), including its conductivity, cationic transference number, hydrolysis, Al-current collector corrosion-protection ability and its cycling performance with some electrode materials. Some Al-corrosion studies were also performed with the help of our recently developed computer controlled impedance scanning electrochemical quartz crystal microbalance (EQCM) that proofed to be a useful tool for battery material investigations. 相似文献
55.
G. Schmitz C. Ene H. Galinski R. Schlesiger P. Stender 《JOM Journal of the Minerals, Metals and Materials Society》2010,62(12):58-63
In recent years, atom probe tomography has advanced to an outstanding tool of analyzing interfacial chemistry in nanostructured
materials. In this article, quantitative measurements of the natural width of multilayer interfaces and of segregation at
grain boundaries and even at separate triple junctions of the boundary structure are presented and their physical consequences
discussed. 相似文献
56.
57.
Dr Niels Grabow David P. Martin Klaus‐Peter Schmitz Katrin Sternberg 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2010,85(6):744-751
Stents are structural implants with widespread clinical use in vascular intervention to re‐open stenotic vessels for the treatment of coronary artery disease and peripheral arterial occlusive disease. Apart from their mechanical function, current drug‐eluting stents (DES) utilize local drug delivery from a drug‐incorporated permanent polymer coating to prevent in‐stent restenosis. This delayed closure of the stented vessel is considered one of the major limitations of conventional bare metal stents (BMS). The long‐term safety of DES, however, is still under debate, with reported cases of delayed healing, late thrombosis and hypersensitivity demanding further evolution in this field. A promising approach to circumvent the limitations of first generation DES is the application of degradable polymer coatings in second generation DES, and fully absorbable polymer stents. From a materials and engineering perspective, this paper provides a mini‐review of current clinically relevant DES technology and recent advancements in the development of stents from degradable polymeric materials as an alternative to permanent BMS and DES. This review, includes work on degradable stents and coatings based on blends of polylactic acid and the microbially‐produced poly(4‐hydroxybutyrate). Copyright © 2009 Society of Chemical Industry 相似文献
58.
In this work we present studies on applicability of transition metal additives as sintering and electrical conductivity aids for cerium gadolinium oxide electrolyte. The nanosized Ce0.85Gd0.15O1.925 powder obtained by coprecipitation method was modified with Cr3+, Fe3+, Ni2+ or Cu2+ ions. Using high-intensity high-resolution X-ray powder diffraction data we have determined that Cr, Fe and Ni ions do not incorporate into the cerium gadolinium oxide surface or bulk when sintered at 1300 °C, but react with Gd ions to form Cr0.9Gd0.1O, GdFeO3 and GdNiO3 phases, while Cu incorporates in the material up to 0.7 mol% with a significant fraction of remaining material showing poorly crystalline CuO phase. The nanosized Ce0.85Gd0.15O1.925 material shows already improved sintering properties than previous reports but full sintering is not achieved below 1300 °C, however Cr, Fe and mainly Cu impregnation allows full sintering at 1300 °C. 0.5 mol% Ni impregnated material sintered at 1500 °C shows enhanced grain boundary conductivity that probably indicates that Ni incorporates into Ce0.84Gd0.15O1.925 above 1300 °C. The global results indicate, however, that optimization of ceria microstructure is at least of equal importance for sinterability and grain boundary conductivity than impregnation of the material with transition metal ions. 相似文献
59.
Bruno Schmitz 《国际钢铁研究》2001,72(11-12):522-527
To promote continuous dry coatings for steel strip by PVD, CRM develops its own JVD (jet vapour deposition) simulator and applies an economical integration strategy combining continuous annealing of steel and vapour deposition by JVD. The JVD system is a very compact system, characterised by a high productivity, a very high metal yield, possibility of working at high partial pressure (up to 1 mbar), homogeneous metal distribution and alloy composition and good coating adherence. It was verified that continuous annealing is a very efficient surface pre‐treatment for steel strip in a wide range of industrial dew points. No additional thermal energy is needed for strip heating since this PVD system is introduced in the end section just after continuous annealing. Application to the Zn‐Mg system is described. Influence of annealing parameters, residual gas pressure, coating speed, steel strip temperature and chemistry are discussed. 相似文献
60.
Schmitz J. Tuinhout H.P. Kretschmann H.J. Woerlee P.H. 《Device and Materials Reliability, IEEE Transactions on》2001,1(3):150-157
This work quantitatively compares soft breakdown identification methods for constant voltage stress of large-area nMOS capacitors (up to 10 mm2) with 1.8- to 12-nm gate-oxide thickness (with negative gate voltage). We conclude that in the studied range, breakdown is identified more reliably with a current step trigger than through increased current fluctuation. We present a method to quantify the system background noise, and show results of data filtering algorithms that significantly enhance the ratio between the breakdown signal and background noise level 相似文献