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21.
The objective of the present study was to generate submicrometer calcium hydroxide aerosols and to investigate the effectiveness of such aerosols in sulfur capture. The effectiveness of SO2 removal by Ca(OH)2 aerosol has been investigated in an isothermal reactor. Ca(OH) 2 aerosol was generated by a novel fluidizer system in which submicrometer-sized powders were entrained in gases. SO2 was added to this aerosol to a concentration of 2000 ppm. The aerosol-SO2 mixture was heated to 550°C-750°C in an isothermal tube reactor. The SO2 removal efficiency, which varied from 20% to 70%, was determined to be a function of the aerosol concentration, reactor temperature and residence time. The fraction of aerosol reacted was not affected strongly by the aerosol concentration. The reaction kinetics were determined from the experimental data using a simple analytical model in which the rate is first order in both SO2 and calcium hydroxide aerosol concentrations.  相似文献   
22.
Explored the construct validity of transactional analysis (TA) ego state concepts. Ego states are defined as coherent systems of thoughts, feelings, and behaviors. 65 university students seeking therapy and 95 university students not receiving therapy completed the Adjective Checklist (ACL) and the Brief Symptom Inventory (BSI). Ego state scores from the ACL correlated with BSI psychological distress in predicted directions. Four of the 5 TA ego state scores differentiated Ss seeking therapy from Ss not seeking therapy. Furthermore, ego state scores changed over the course of therapy, indicating a reduction of distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
In order to implement the Accreditation Board for Engineering and Technology (ABET) engineering criteria, it is important for engineering educators to understand different types of knowledge and how these types relate to the outcomes described in Criterion 3. This paper first provides a heuristic for framing a program's educational objectives by identifying exemplars of the types of engineers a program seeks to graduate. Three sections then follow, each addressing categories of knowledge: tacit knowledge, four types of knowledge that can either be tacit or explicit, and knowledge created and shared in teams. Examples of the relationship of traits of knowledge to the outcomes in Criterion 3 are provided. The paper concludes with a brief discussion of how these types of knowledge are imbued in engineering students at the University of Virginia, as well as suggestions for additional ways in which they could be infused into engineering curricula.  相似文献   
24.
A 3·2 kb EcoRI fragment of yeast Saccharomyces cerevisiae was entirely sequenced. Two new open reading frames were identified. The first is extremely hydrophobic, and would likely be an integral membrane protein. It has significant similarity to only one reported gene, a gene of unknown function from Drosophila melanogaster. The second ORF is asparagine-rich and very serine-rich, with a remarkable stretch of nearly 26 consecutive asparagine residues comprised of the same codon. It has no significant similarity to any reported gene. The fragment maps to chromosome II on the left arm between the CDC27 and ILS1 loci. The nucleotide sequence reported in this paper has been deposited in the GenBank database with the Accession Number M89908.  相似文献   
25.
MKT1 is required for m aintenance of K2 above 30°C in strains with the L-A-HN variant of the L-A double-stranded RNA virus of Saccharomyces cerevisiae. We report that MKT1 encodes a 92 979 Da protein with serine-rich regions and the retroviral protease signature, DTG, but with no substantial homology to proteins presently in the databases. This sequence is available from GenBank under Accession Number U09129.  相似文献   
26.
Metelli's theory of the perception of translucency models the effective reflectance of a translucent sheet on a background as a partitive mixture of the color of the sheet and the color of the background. In the achromatic case, the usable (that is, scale-invariant) rules governing the apparent reflectances are the same as those that would emerge from the Kubelka-Munk theory. For chromatic translucency, the relationships are more complex, but a set of rules still emerge from the partitive-mixture theory that are invariant to tradeoffs between illuminant and reflectances. This column sets forth the rules in the hopes that they will have graphical applications, both on computer VDUs and in hardcopy.  相似文献   
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Coating experiments were conducted to assess the inter-unit uniformity using individual weight gains of glass beads. Applying more aqueous film coating and prolonging the film-coating process by diluting the coating suspension did improve the coating variability among glass beads. It appears that run time is an important underlying factor which affecting the inter-unit coating uniformity.  相似文献   
30.
A generalized parameter-level statistical model, called statistical MOS (SMOS), capable of generating statistically significant model decks from intra- and inter-die parameter statistics is described. Calculated model decks preserve the inherent correlations between model parameters while accounting for the dependence of parameter variance on device separation distance and device area. Using a Monte Carlo approach to parameter sampling, circuit output means and standard deviations can be simulated. Incorporated in a CAD environment, these modeling algorithms will provide the analog circuit designer with a method to determine the effect of both circuit layout and device sizing on circuit output variance. Test chips have been fabricated from two different fabrication processes to extract statistical information required by the model. Experimental and simulation results for two analog subcircuits are compared to verify the statistical modeling algorithms  相似文献   
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