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Test structures intended for performance verification of transmission line pulse (TLP) systems have been designed and tested. They consist of simple resistors in either copper or silicide clad polysilicon. The copper structures proved unsuitable due to excess heating and melting of any reasonable geometry. The silicide clad polysilicon proved more successful. A simple model of resistive heating accounts for observed nonlinearity in the structures under high current stress. The availability of a verification structure on wafer ensures the proper performance of the full measurement system, including contact to the wafer and the pad structure, ensuring valid TLP measurements. 相似文献
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The design of industrial distillation columns is normally based on estimated values of plate efficiencies. Several different plate efficiency models have been proposed in the literature and among them the one presented by Murphree is widely used in spite of its limitations. However the difficulties involved in the use of Murphree's model are not present if Hausen's model is considered.In the present paper a comparative study of the two models considering both binary and multicomponent systems is presented. A graphical relationship beExperimental composition profiles obtained in small laboratory columns with binary and ternary systems are interpreted in terms of Hausen efficiencies.It is argued that the use of the Hausen efficiency model should be wider as it overcomes limitations of Murphree's model and is in agreement with physi 相似文献
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International Journal of Coal Science & Technology - A mutualistic relationship between grasses, coal-degrading fungi, and arbuscular mycorrhizal fungi was proposed to account for the... 相似文献
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Lee Kibeom; Ashton Michael C.; Pozzebon Julie A.; Visser Beth A.; Bourdage Joshua S.; Ogunfowora Babatunde 《Canadian Metallurgical Quarterly》2009,96(2):460
The authors obtained self- and observer reports of personality from pairs of well-acquainted college students. Consistent with previous findings, results of Study 1 showed strong cross-source agreement for all 6 HEXACO personality factors (rs ≈ .55). In addition, the authors found modest levels of similarity (r ≈ .25) between dyad members' self-reports on each of 2 dimensions, Honesty-Humility and Openness to Experience. For these same 2 factors, dyad members' self-reports were correlated with their observer reports of the other dyad member (r ≈ .40), thus indicating moderately high assumed similarity. In Study 2, Honesty-Humility and Openness to Experience were the 2 personality factors most strongly associated with the 2 major dimensions of personal values, which also showed substantial assumed similarity. In Study 3, assumed similarity was considerably stronger for close friends than for nonfriend acquaintances. Results suggest that assumed similarity for Honesty-Humility and Openness to Experience reflects a tendency to overestimate one's similarity to persons with whom one has a close relationship, but only on those personality characteristics whose relevance to values gives them central importance to one's identity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The rate constant k2 has been measured in flames of H2 + O2 + N2 for the ionization of alkali metal atoms M in collisions with flame species X in . Results are compared with every previously reported measurement of k2 in similar flames for each alkali metal. It is concluded that , ml molecule ?1 sec?1, where V is the ionization potential of the alkali metal atom and T the temperature. k2 does not depend on flame composition and is the same for each alkali to a good approximation.The third-order recombination rate constant k?2 for the reverse of (II) can be written as , ml2 molecule?2 sec?1. There is no significant dependence of k?2 on flame composition or on which alkali metal is considered. These facts enable the rates of the forward and reverse processes in (II) to be estimated in flames generally. 相似文献
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ABSTRACT: Five strains of bifidobacteria were screened for β-glucosidase activity using p-nitrophenyl-β-D-glucopyranoside as the substrate, and selected strains were used to ferment soymilk. Enumeration of viable bifidobacteria and quantification of isoflavones using HPLC were performed at 0, 12, 24, 36, and 48 h of incubation. Four strains produced β-glucosidase. B. pseudolongum and B. longum -a displayed the best growth in soymilk, with an increase of 1.3 log10 CFU/mL after 12 h. B. animalis, B. longum -a, and B. pseudolongum caused hydrolysis of isoflavone malonyl-, acetyl- and β-glucosides to form aglycones, and transformed daidzein to equol in soymilk. Fermentation of soymilk with Bifidobacterium sp. resulted in a significant increase (p < 0.05) in the concentration of aglycones. 相似文献
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Prasad S Thenkabail Eden A Enclona Mark S Ashton Christopher Legg 《Remote sensing of environment》2004,90(1):23-43
The goal of this research was to compare narrowband hyperspectral Hyperion data with broadband hyperspatial IKONOS data and advanced multispectral Advanced Land Imager (ALI) and Landsat-7 Enhanced Thematic Mapper Plus (ETM+) data through modeling and classifying complex rainforest vegetation. For this purpose, Hyperion, ALI, IKONOS, and ETM+ data were acquired for southern Cameroon, a region considered to be a representative area for tropical moist evergreen and semi-deciduous forests. Field data, collected in near-real time to coincide with satellite sensor overpass, were used to (1) quantify and model the biomass of tree, shrub, and weed species; and (2) characterize forest land use/land cover (LULC) classes.The study established that even the most advanced broadband sensors (i.e., ETM+, IKONOS, and ALI) had serious limitations in modeling biomass and in classifying forest LULC classes. The broadband models explained only 13-60% of the variability in biomass across primary forests, secondary forests, and fallows. The overall accuracies were between 42% and 51% for classifying nine complex rainforest LULC classes using the broadband data of these sensors. Within individual vegetation types (e.g., primary or secondary forest), the overall accuracies increased slightly, but followed a similar trend. Among the broadband sensors, ALI sensor performed better than the IKONOS and ETM+ sensors.When compared to the three broadband sensors, Hyperion narrowband data produced (1) models that explained 36-83% more of the variability in rainforest biomass, and (2) LULC classifications with 45-52% higher overall accuracies. Twenty-three Hyperion narrowbands that were most sensitive in modeling forest biomass and in classifying forest LULC classes were identified and discussed. 相似文献
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