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191.
Kinetic knowledge is of great importance in achieving good control of the pyrolysis and gasification process and optimising
system design. An overall kinetic pyrolysis scheme is therefore addressed here. The kinetic modelling incorporates the following
basic steps: the degradation of the virgin biomass materials into primary products (tar, gas and semi-char), the decomposition
of primary tar into secondary products and the continuous interaction between primary gas and char. The last step is disregarded
completely by models in the literature. Analysis and comparison of predicted results from different kinetic schemes and experimental
data on our fixed bed pyrolyser yielded very positive evidence to support our kinetic scheme.
Project (No. 2001CB409600) Supported by the National Key Basic Research Program (973) of China 相似文献
192.
Parents' role in the decision process 总被引:1,自引:0,他引:1
193.
Fourteen behavioral measures were ranked according to their ability to differentiate performances of a wild population of mice from three domestic inbred strains. These “wildness” rankings were then analyzed for their ability to predict genetic and Genotype by Environment interactions. Genetic parameters were derived from analysis of three inbred domestic strains and their three hybrid crosses via the diallel technique of genetic analysis. Genotype by Environment interactions were assessed both as mean differences in stock performances resulting from rearing in a laboratory vs naturalistic environment and as differences in environmental variability within stock genotypes. Behavioral characters ranking high on “wildness” failed to demonstrate any unitary pattern of Genotype by Environment interactions. The diallel genetic analysis revealed many examples of additive variation but relatively few examples of dominant variation. An extremely wide range of interactions occurred between genotype and rearing environments, with “wildness” and “developmental homeostasis” concepts both failing to account for all the observed interactions. 相似文献
194.
195.
196.
Thomas H. Turney 《Learning & behavior》1976,4(4):363-366
Long-Evans rats were trained on an easy simultaneous discrimination problem and then transferred to a hard discrimination problem. The discriminanda were different orientations of stripes. In Experiment I, transfer was intradimensional with stimulus generalization controlled. The easy-to-hard effect was not found. In Experiment II transfer was intradimensional and either compatible (nonreversal) or incompatible (reversal). With compatible transfer, rats trained on a prior easy problem learned the hard problem faster than rats trained only on the hard problem. Persistent negative transfer was found with incompatible transfer. Attention was not supported as underlying the easy-to-hard effect. Explanations based on specific sources of intradimensional transfer, such as stimulus generalization or adaptation level, are suggested. 相似文献
197.
198.
Attitudinal data were collected for a sample of 492 parents and public school children before implementation of a metropolitan desegregation plan and for 2 years after implementation. The variables measured included racial attitudes, feelings out desegregation, and school-related attitudes. There were small but significant changes on 7 of the 11 measures, with most of the changes occurring during the first year. There were race and grade-level differences on some of the variables before desegregation, but race and grade level were generally not related to changes over time.This research has been supported by a grant from the Rockefeller Foundation, Division of Social Sciences. 相似文献
199.
William H. Angoff 《Journal of Educational Measurement》1989,26(4):323-336
This study examines the claim that attempting, or guessing at, more items yields improved formula scores. Two samples of students who had taken a form of the SA T- Verbal consisting of three parallel half-hour sections, were used to form the following scores on each of the three sections: the number of attempts, a guessing index, the formula score, and (indirectly) an approximation to an ability score. Correlations were obtained separately for the two samples between the attempts, and the guessing index, on one section, the formula score on a second section, and ability as measured by the third section. The partial correlations obtained hovered near zero, suggesting, contrary to conventional opinion, that, on average, attempting more items and guessing are not helpful in yielding higher formula scores, and that, therefore, formula scoring is not generally disadvantageous to the student who is less willing to guess and attempt an item that he or she is not sure of. On closer examination, however, it became clear that the advantages of guessing depend, at least in part, on the ability of the examinee. Although the relationship is generally quite weak, it is apparently the case that more able examinees do tend to profit somewhat from guessing, and would therefore be disadvantaged by their reluctance to guess. On the other hand, less able examinees may lower their scores i f they guess. 相似文献
200.
C. DEAN MILLER WESTON H. MORRILL ALLEN E. IVEY CHERYL J. NORMINGTON MAX R. UHLEMANN 《Counselor Education & Supervision》1973,13(1):14-23
Microcounseling techniques were used to conduct an experimental study. The objective was to train naive college students who were interested in counseling to assess clients' attitudes toward guidance tests. A correlation of .797 was obtained between clients' ratings of attitudes toward tests and the trainees' ratings of clients' attitudes toward tests. Findings were consistent with the results of other microcounseling studies. Individual differences among the trainees were noted and comparisons were made between the trainees' own ratings, judges' ratings, and clients' ratings of trainees. Lack of a control group imposes a serious limitation on interpretation of the results. 相似文献