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排序方式: 共有447条查询结果,搜索用时 15 毫秒
51.
Richard Le Heron Glen W. Atkinson Henry Teune Greg Mason Henk Voogd Brenda J. Moscove Patricia Gober Thomas A. Reiner Richard F. Curtis Stephen F. Seninger W. W. Hall Jr. John E. Keith M. Van Naelten R. W. Keyes John Huttman Robert B. Weeden Clarence G. Ray Steven E. Daniels F. Larry Leistritz Patrizia Spinetti Peter D. Beaulieu F. J. Potgieter David L. Barkley Charles A. Berry Jean E. Weber Wieslaw Rozlucki Jesse Burkhead John R. Ottensmann Noel D. Uri Erlet Cater J. Barry Riddell Ernesto Quintanilla John F. McDonald Jon R. Miller Stan Czamanski 《The Annals of Regional Science》1986,20(1):87-144
52.
Dane L. Clark Brenda J. Hollo Paul K. Tornstrom Robert E. Turnbull Tom R. Woodley 《乙烯基与添加剂工艺杂志》1986,8(1):27-31
Although the classification of lubricants can be misleading, the classification of their actions is not only possible but very useful. By considering the basic actions which affect PVC dryblend fusion, a better understading of the characteristics and advantages of additives can be realized. The antimony and tin stabilizers used in this study have been characterized by the affects on PVC dryblend fusion. Production extrusion results confirm the laboratory classifications. 相似文献
53.
Triphenylchloromethane and p-toluenesulfonyl chloride were reacted with chopped or powdered cellulose, with and without premercerization, to form trityl–cellulose ethers or tosyl–cellulose esters. Powdered and premercerized cellulose samples were more readily derivatized. Differential scanning calorimetric (DSC) and thermogravimetric (TG) analyses were performed in nitrogen on these derivatives. DSC and TG thermograms were affected by the particular derivative and the degree of substitution. The decomposition temperatures for both derivatives were lower than for the unmodified cellulose. Trityl cleavage may have been detected by DSC as a broad endothermic area showing no weight loss that preceded the major endothermic decomposition peak. Decomposition temperatures were lowered, but not sufficiently to prevent decomposition products from being combustible. No increase in residue was effected. Thermal decomposition of tosyl–cellulose was substantially different from that of the trityl derivative. As the degree of tosyl substitution increased, decomposition occurred at lower temperatures as an increasing exotherm. Tosyl derivatives all produced high residues. These changes in thermal characteristics were indicative of increased flame resistance. Oxygen index (OI) values relate to flame resistance and show that tritylation was detrimental to the cellulose and that tosylation imparted some degree of flame resistance. 相似文献
54.
Medium weight twill fabrics constructed from cotton and cotton blended with polyester and/or wool were analyzed under nitrogen by three thermoanalytical techniques. Fabrics were tested both before and after treatment with [tetrakis(hydroxymethyl)phosphonium] sulfate (THPS), urea, and trimethylolmelamine. The presence of all fibers was distinguishable in differential scanning calorimetric analysis (DSC) of untreated fabrics; the relative positions of the endothermic, decomposition peak temperatures were only slightly changed. After flame-retardant (FR) treatment, the blended cotton and wool fibers were altered. Both fibers decomposed as exotherms during DSC analysis. These data supported earlier microscopical, X-ray evidence that wool fibers were actually reacting with the FR treatment. The two DSC peaks for polyester polymer melting and decomposing remained unaffected by either blending with other fibers or the presence of the FR finish on the fabric. There was excellent agreement between DSC peak temperatures and the temperature of maximum rate of weight loss obtained from thermogravimetric analysis (TGA). Blending cotton with either of these fibers increased the residue measured after TGA. The increased residue correlated with increased flame resistance as measured by the 45° angle, edge-ignition burning rate test. 相似文献
55.
56.
Interviewed 54 college females individually for 40 min about how they were influenced by friends, family, and persons in authority. The interviewer disclosed experiences, attitudes, and beliefs similar and dissimilar to those revealed by the S 0, 4, or 12 times during the interview. Such disclosures occurred prior to (modeling situation) or immediately after (reinforcement situation) S disclosures. An intermediate number of disclosures resulted in significantly more S disclosures and led to the interviewer's being described as significantly more empathic, warm, and congruent. Timing of interviewer disclosures had no effect. Results suggest that an intermediate level of interviewer self-disclosure may best initiate reciprocity of disclosure, which in turn can lead to more positive reactions to the interviewer. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Poulin-Dubois Diane; Serbin Lisa A.; Kenyon Brenda; Derbyshire Alison 《Canadian Metallurgical Quarterly》1994,30(3):436
The aim of this study was to seek evidence of intermodal knowledge about gender in infants that would provide direct evidence of the existence of gender categories during the 1st yr of life. In Exp 1, 20 9- and 24 12-mo-olds were presented with pairs of male and female pictures with a female or male voice presented simultaneously. Ss spent significantly more time looking at the pictures matching the voices than at the same pictures paired with mismatching voices, but only in the case of female stimuli. Comparison to chance level performance suggested that the matching effect was more consistent in older Ss. In Exp 2, 20 9-mo-olds were tested with a set of highly stereotypical faces and distinctive male and female voices. Ss showed a preference for the faces matching the voices, but this effect was again restricted to female stimuli. Results of both studies suggest that intermodal knowledge about gender develops during the 2nd half of the 1st yr. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Discusses database searching strategies for topics in psychology, using, as an example, the present authors' (1988) bibliography of research on Black males in the US, compiled from the PsycINFO database. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
This pilot study focused on the effects of assertion training on 14 physically disabled undergraduates' acceptance of disability. A pretest–posttest control group design was utilized. Ss were randomly assigned to either a treatment group or a no-treatment control group. The hypotheses analyzed were that Ss given assertion training would show increases in Acceptance of Disability Scale scores, self-concept/esteem scores (Rathus Assertiveness Scale), and social interaction skills scores (Behavioral Observation Scale) when compared with individuals who did not experience assertion training. Significant results were obtained for all hypotheses indicating that the groups differed in acceptance of disability, self-concept, and social interaction. The study suggests that assertion training may be effective for increasing acceptance of disability in physically disabled students. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Brenda M. Fox Geoffrey Hallas John D. Hepworth Donald Mason 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1980,30(1):317-323
The hydrolysis of Brilliant Green has been studied over the pH range 6–11. In neutral aqueous solution and in the absence of light, the system reaches equilibrium. In alkaline solution, complete conversion into the dye base occurs. Rate constants and activation parameters have been obtained for the hydrolysis and a reaction scheme is proposed. 相似文献