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51.
The bubble eater is a device which can sense, capture, and recycle bubble gas in a bubbling fluidized bed. The theory describing the enhancement of reactant gas conversion are presented and illustrated by means of a numerical example. 相似文献
52.
MODELING LIQUID MASS TRANSFER IN HIGEE SEPARATION PROCESS 总被引:1,自引:0,他引:1
Correspondence concerning this paper should be addressed to Professor Richard S.H. Mah. Hsien-Hsin Tung is now affiliated with Department of Chemical Engineering, California Institute of Technology
Penetration theory is used to describe the liquid mass transfer in Higee separation process. Within a possible range of effective areas, it is shown that the predicted mass transfer coefficients are in reasonable agreement with the estimated mass transfer coefficients. The estimated coefficients were calculated from the experimental data and the possible effective areas. Hence it is concluded the penetration theory is generally applicable to describe liquid mass transfer in Higee separation process. The comparison also suggests that liquid mixing at the junctions of packing materials may be more complete in Higee process than in traditional process. 相似文献
Penetration theory is used to describe the liquid mass transfer in Higee separation process. Within a possible range of effective areas, it is shown that the predicted mass transfer coefficients are in reasonable agreement with the estimated mass transfer coefficients. The estimated coefficients were calculated from the experimental data and the possible effective areas. Hence it is concluded the penetration theory is generally applicable to describe liquid mass transfer in Higee separation process. The comparison also suggests that liquid mixing at the junctions of packing materials may be more complete in Higee process than in traditional process. 相似文献
53.
Basicity values have been determined for series of monoazo dyes incorporating a pyrrolidino or a piperidino moiety. In general, the pKa value is found to decrease as the donor capacity of the terminal nitrogen atom decreases.The basicities of the 4'-substituted piperidinoazobenzenes decrease as the electron withdrawing strength of the 4'-substituent increases. However, the pKa values of the related pyrrolidino compounds appear to be insensitive to the substituent. 相似文献
54.
55.
Richard J. Murray 《Information Systems Management》1991,8(3):7-15
In today's competitive world, many organizations are pursuing total quality improvement programs, and as a result of these initiatives, are seeking to define world class capabilities. The organizations with these aspirations are trying to improve product and service quality, business process quality, or delivered quality, and are becoming aware that information technology is playing a more substantial role in realizing these quality goals. 相似文献
56.
Overcoming contextual limitations on problem-solving transfer. 总被引:1,自引:0,他引:1
Five experiments investigated transfer from multiple analogs to a superficially dissimilar target problem. When subjects explicitly compared the analogs and then immediately attempted to solve the target problem in the context of a single experiment, transfer was obtained with significant frequency even without a hint that the analogs and target were related. Prehint transfer was sharply reduced or eliminated when the source analogs and the target were presented in different contexts, even when the transfer test was immediate. However, prehint transfer was enhanced, even after a context shift and a week-long delay between reading the source analogs and solving the problem, when the following conditions were met: The target problem was reworded slightly to emphasize a structural feature that it shared with the analogs; three rather than two source analogs were provided; and detailed, schema-oriented questions were used to help subjects focus on the problem-relevant aspects of the stories. Although spontaneous transfer between small numbers of dissimilar analogs is difficult to obtain, it can be achieved by manipulations that foster abstraction of a problem schema from the training examples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Carl A. Soderstrom Patricia C. Dischinger Gordon S. Smith J.Richard Hebel David R. McDuff David A. Gorelick Timothy J. Kerns Shiu M. Ho Kathleen M. Read 《Accident; analysis and prevention》1997,29(6):715-721
A structured in-depth interview employing standardized criteria was used to determine the prevalence of lifetime and current alcohol dependence (alcoholism) in unselected consecutive patients admitted to a regional Level I trauma center. Of 629 patients, 157 (25.0%) were current alcoholics at the time of injury. An additional 87 (13.8%) were diagnosed as lifetime non-current alcoholics. There was no significant difference in the rates of current alcohol dependence among patients injured in vehicular crashes (23.5%), other unintentional trauma victims (29.3%), and those injured as a result of violence (24.6%). Of BAC + (blood alcohol concentration positive) patients, 54.5% were current alcoholics. However, 14.4% of alcohol-negative patients were also diagnosed as alcohol dependent. 相似文献
58.
Sodowsky Gargi Roysircar; Taffe Richard C.; Gutkin Terry B.; Wise Steven L. 《Canadian Metallurgical Quarterly》1994,41(2):137
Presents the Multicultural Counseling Inventory (MCI), a self-report instrument that measures multicultural counseling competencies. Study 1 comprised 604 psychology students, psychologists, and counselors in a midwestern state. In Study 2, respondents were a national random sample of 320 university counselors. Instrument analysis included exploratory principal-axis factor analysis with oblique rotation, assessment of factor congruence between the factor structures of the 2 samples, LISREL confirmatory factor analysis to test the relative goodness of fit of 6 competing factor models of the MCI, and tests of internal consistency reliabilities. Results indicate that the MCI has 4 factors: Multicultural Counseling Skills, Multicultural Awareness, Multicultural Counseling Relationship, and Multicultural Counseling Knowledge. A higher order, more general multicultural counseling factor is also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
Assessed whether resting anterior asymmetry would discriminate individual differences in repressive-defensive coping styles. In 2 sessions, resting electroencephalogram was recorded from female adults during 8 60-sec baselines. Ss were classified as repressors or nonrepressors on the basis of scores on the Marlowe-Crowne Social Desirability Scale (MC), the State-Trait Anxiety Inventory (STAI), and the Beck Depression Inventory (BDI). In midfrontal and lateral frontal sites, repressors demonstrated relative left hemisphere activation when compared with other groups. The MC, but not the STAI or the BDI, contributed unique variance to frontal asymmetry. Relative left frontal activation may be linked to a self-enhancing regulatory style that promotes lowered risk for psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Purification and characterization of the alpha-agarase from Alteromonas agarlyticus (Cataldi) comb. nov., strain GJ1B 总被引:2,自引:0,他引:2
The phenotypic features of strain GJ1B, an unidentified marine bacterium that degrades agar [Young, K. S. Bhattacharjee, S. S. & Yaphe, W. (1978) Carbohydr. Res. 66, 207-212], were investigated and its agarolytic system was characterized using 13C-NMR spectroscopy to analyse the agarose degradation products. The bacterium was assigned to the genus Alteromonas and the new combination A. agarlyticus (Cataldi) is proposed. An alpha-agarase, i.e. specific for the alpha(1-->3) linkages present in agarose, was purified to homogeneity from the culture supernatant by affinity chromatography on cross-linked agarose (Sepharose CL-6B) and by anion-exchange chromatography (Mono Q column). The major end product of agarose hydrolysis using the purified enzyme was agarotetraose. Using SDS/PAGE, the purified alpha-agarase was detected as a single band with a molecular mass of 180 kDa. After the affinity-chromatography step, however, the native molecular mass was approximately 360 kDa, suggesting that the native enzyme is a dimer which is dissociated to active subunits by anion-exchange chromatography. The isolectric point was estimated to be 5.3. Enzyme activity was observed using agar as the substrate over the pH range 6.0-9.0 with a maximum value at pH 7.2 in Mops or Tris buffer. The enzyme was inactivated by prolonged treatment at a pH below 6.5, or by temperatures over 45 degrees C or by removing calcium. In addition, a beta-galactosidase specific for the end products of the alpha-agarase was present in the alpha-agarase affinity-chromatography fraction, probably as part of a complex with this enzyme. The degradation of agarose by this agarase complex yielded a mixture of oligosaccharides in the agarotetraose series and the agarotriose series, the latter consisting of oligosaccharides with an odd number of galactose residues. 相似文献