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951.
Billy Wu Michael A. Parkes Vladimir Yufit Luca De Benedetti Sven Veismann Christian Wirsching Felix Vesper Ricardo F. Martinez-Botas Andrew J. Marquis Gregory J. Offer Nigel P. Brandon 《International Journal of Hydrogen Energy》2014
The design and test of a 9.5 kWe proton exchange membrane fuel cell passively coupled with a 33 × 1500 F supercapacitor pack is presented. Experimental results showed that the system reduced dynamic loads on the fuel cell without the need for additional DC/DC converters. Fuel efficiency gains of approximately 5% were achieved by passive hybridisation in addition to addressing two main operational degradation mechanisms: no-load idling and rapid load cycling. 相似文献
952.
953.
Georgy Shevlyakov Vladimir Shin Seokhyoung Lee Kiseon Kim 《International Journal of Adaptive Control and Signal Processing》2014,28(9):848-858
To design highly efficient and robust detectors of a weak signal, an asymptotic approach to stable estimation exploiting redescending score functions is used. Two new indicators of robustness of detection, the detection error sensitivity and detection stability, are introduced. The optimal Neyman–Pearson rules maximizing detection efficiency under the guaranteed level of detection stability are written out. Under heavy‐tailed noise distributions, the proposed asymptotically stable detectors based on redescending score functions, namely, the minimum error sensitivity and the radical ones, outperform conventional linear bounded Huber's and redescending Hampel's detectors both on small and large samples. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
954.
Assessment of process parameters on the production of diglycerides rich in omega-3 fatty acids through the enzymatic glycerolysis of fish oil 总被引:1,自引:0,他引:1
Maria Manuela Camino Feltes J. Vladimir Oliveira Helen Treichel Jane Mara Block Débora de Oliveira Jorge Luiz Ninow 《European Food Research and Technology》2010,231(5):701-710
The main objective of this work is to present new experimental information concerning the effect of relevant process parameters
related to the production of diglycerides by enzymatic glycerolysis of fish oil. Reaction products can be applied as ingredients
in food industry, joining the emulsifying properties of partial glycerides along with the nutritional benefits attributed
to the omega-3 fatty acids. From preliminary reactions, conversion was higher for a solvent- and surfactant-free system but
the long time to reach appreciable amounts of diglycerides may be a drawback for practical purposes. To overcome this problem,
the addition of tert-butanol revealed to be relevant, leading to high diglycerides contents in short times. The system containing Tween 65 led
to the highest amount of diglycerides. This study described the feasibility of enzymatic synthesis of diglycerides rich in
EPA and DHA in short reaction times as well by using a more environmentally friendly process. 相似文献
955.
956.
Carbon fiber composite connections for hollow-core precast concrete wall panels have been investigated with respect to bond behavior. A panel assembly made up of three precast concrete walls was loaded in the in-plane direction using a cyclic quasi-static load, which was transferred to the wall interface as a shear force. The application of the carbon-fiber-reinforced polymer (CFRP) composite was varied in the covered area, number and orientation of plies, and the concrete surface preparation. An expression, which compares well with the experimental findings, is presented for the effective bond length of carbon fiber composite sheets. The effective bond length of the connection depends on the peel-off shear strength of the concrete, the maximum tensile strain in the composite, the modulus of elasticity of the composite, and thickness of the composite plate. 相似文献
957.
Recently developed kinetic model for homoepitaxial growth is extended to the case of heteroepitaxy (without lattice mismatch) by introducing different adatom surface mobilities in the first layer (heterodiffusion) and in all the next layers (self-diffusion). With this model the effect of two adatom mobilities as a function of the Schwoebel step-edge barrier is studied with an emphasis on the growth mode transitions. It is shown that the difference between homo- and heteroepitaxy is confined to the first few monolayers and is crucially sensitive to the ratio between the hetero- and self-diffusion coefficients: lower heterodiffusion coefficient with respect to that of self-diffusion improves essentially epitaxial growth and vice-versa. This is important for growing smooth ultrathin layers needed in modern nanotechnology. Island density kinetics in successive growing layers is studied and it is found that in smooth growth regime it acquires eventually (after deposition approx. 10 monolayers) a universal scaling form and corresponding scaling exponents have been determined. 相似文献
958.
959.
Electron structure of a silicon quantum dot doped with a shallow hydrogen-like donor has been calculated for the electron
states above the optical gap. Within the framework of the envelope-function approach we have calculated the fine splitting
of the ground sixfold degenerate electron state as a function of the donor position inside the quantum dot. Also, dependence
of the wave functions and energies on the dot size was obtained. 相似文献
960.
Raushan B. Koizhaiganova Vladimir B. Sigitov Larisa A. Bimendina Sarkyt E. Kudaibergenov 《Polymer Bulletin》2005,53(3):161-168
Summary Novel linear and crosslinked polyelectrolytes based on acetoacetic ester and acrylic acid were synthesized for the first time via Michael addition reaction followed by radical polymerization. The structure and properties of polyelectrolytes were characterized by FTIR, Raman and NMR spectroscopy, TGA, DSC, GPC, viscometry and potentiometric titration. Considerable influence of water content on the swelling rate of hydrogels was established. The swelling-deswelling properties of hydrogels were studied in dependence of pH, ionic strength and in water-organic solvent mixtures. 相似文献