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31.
Weak amylopectin gels have been formed directly following dissolution of waxy maize granules. Rheological characterisation of these gels has been carried out as a function of stress and frequency. The gels are visually clear and homogeneous, and environmental scanning electron microscopy shows no trace of the original granules remaining. It is postulated that the origin of the gel network lies in pairwise aggregation of outer chains of the amylopectin molecules, presumably via double helix formation. However, these pairs of chain segments do not aggregate to develop crystallinity. 相似文献
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Matin Mason 《中国电子商情》2006,(8):24-25
根据主要从事半导体及电子市行业市场调研的机构Databeans调查.电气和电子元件占一般汽车总成本约20%。该公司估计一辆2004年生产的低价位汽车上有150到180个电子元件.而现在生产的高价位汽车上则最少包含400个电子元件。 相似文献
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In this paper, we describe a self-aligned process to produce short-channel vertical power DMOSFETs in 4H-SiC. By reducing the channel length to /spl les/0.5 /spl mu/m, the specific on-resistance of the MOSFET channel is proportionally reduced, significantly enhancing performance. 相似文献
34.
Mohamed Abusnina Helio Moutinho Mowafak Al-Jassim Clay DeHart Mohammed Matin 《Journal of Electronic Materials》2014,43(9):3145-3154
In this work, Cu2ZnSnS4 (CZTS) thin films were prepared by the sulfurization of metal precursors deposited sequentially via radio frequency magnetron sputtering on Mo-coated soda-lime glass. The stack order of the precursors was Mo/Zn/Sn/Cu. Sputtered precursors were annealed in sulfur atmosphere with nine different conditions to study the impact of sulfurization time and substrate temperature on the structural, morphological, and optical properties of the final CZTS films. X-ray fluorescence was used to determine the elemental composition ratio of the metal precursors. Final CZTS films were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). XRD and EDS were combined to investigate the films’ structure and to identify the presence of secondary phases. XRD analysis indicated an improvement in film crystallinity with an increase of the substrate temperature and annealing times. Also indicated was the minimization and/or elimination of secondary phases when the films experienced longer annealing time. EDS revealed slight Sn loss in films sulfurized at 550°C; however, an increase of the sulfurization temperature to 600°C did not confirm these results. SEM study showed that films treated with higher temperatures exhibited dense morphology, indicating the completion of the sulfurization process. The estimated absorption coefficient was on the order of 104 cm?1 for all CZTS films, and the values obtained for the optical bandgap energy of the films were between 1.33 eV and 1.52 eV. 相似文献
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Houwen Tang M. A. Matin Heli Wang Shet Sudhakar Le Chen Mowafak M. Al-Jassim Yanfa Yan 《Journal of Electronic Materials》2012,41(11):3062-3067
A major drawback for CuO as an efficient photocathode in photoelectrochemical (PEC) water splitting is its instability in aqueous solution. In this paper, we report that Ti alloying can enhance the stability of CuO in PEC water splitting but at the cost of reduced crystallinity and optical absorption, and therefore reduced photocurrent. We further report that a balance between the stability and photocurrent can be realized by a bilayer configuration—a thin Ti-alloyed CuO layer on a pure CuO thin film. Our results indicate that the thickness of the top Ti-alloyed CuO layer should be optimized to realize the best stability and photocurrent. 相似文献
37.
Rubayyat Mahbub Takian Fakhrul Md. Fakhrul Islam Mehedi Hasan Arman Hussain M.A. Matin M.A. Hakim 《金属学报(英文版)》2015,28(8):958
The main focus of the research was to correlate the microstructure with dielectric and magnetic properties of Bi1-xBaxFeO3 samples. Bi1-xBaxFeO3 samples(x = 0.1, 0.2 and 0.3) were synthesized by the conventional solid-state reaction method using nano-powders of Bi2O3, Fe2O3, and BaCO3. Thereafter, field emission scanning electron microscope and X-ray diffraction(XRD) techniques were used to examine the structure and phase of the samples. Phase analysis by XRD indicated that the single-phase perovskite structure was formed with possible increment in lattice parameter with increasing Ba doping. Complex permeability(u'iand u'i) measured using impedance analyzer confirmed the increase in magnetic property with increasing Ba doping. Finally, dielectric constant(k) was analyzed as a function of temperature at different frequencies. Dielectric constant as high as 2900 was attained in this research for Bi0.8Ba0.2FeO3 sample due to reduction in leakage current at this composition. 相似文献
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Information-processing time was compared for serial and spatially distributed visual presentations with performance measures that permit the separation of total time into its during-display and post-display components. For all subjects, there was a significant saccadic overhead, that is, less time was required with the serial format, which allowed data access without eye movements. However, the magnitude of the overhead decreased as task complexity increased. All subjects were able to exercise some control over the distribution of total processing time, trading off short during-display times with longer post-display times and vice versa. 相似文献