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设计了乙醇发酵与膜透析耦合系统并进行了试验研究.结果表明,该过程可减少产物乙醇对发酵的抑制作用,膜透析系统的乙醇总量比对照组提高20%~80%,基质转化率提高30%~80%. 相似文献
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Rose Marie Salazar‐Clemea 《The Career development quarterly》2002,50(3):246-256
The article's 1st section provides an overview of the historical development of career counseling in the Philippines from an economic‐political perspective. The 2nd section raises current challenges and concerns, highlighting the need for a career counseling model that would address, among other things, Filipinos' valued characteristics of close family ties and desire for economic progress. 相似文献
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Abstract In recent years, church burnings in the South have attracted a great deal of attention. Many commentators have charged that they are a product of strained race relations throughout the South, and particularly of severe racial tensions in Southern rural areas. In this study we evaluate these claims. We begin by mapping the spatial coordinates of recorded church burnings from 1990 to 1997, and find that church arsons indeed are concentrated in the South. Church burnings, however, are a more urban phenomenon than popular media accounts would suggest. Our analysis then explores the influence of contextual factors (population and locale, racial composition and inequality, so‐cioeconomic conditions, local religious ecology, and patterns of reported crime) on church burnings in counties located in the study region. Logistic regression models confirm that church arsons are most likely to occur in small metropolitan statistical areas (MSAs) and non‐MSA counties containing a city of at least 10,000 residents. Church burnings also are especially likely in counties with a higher percentage of black residents, a larger number of churches relative to the rest of the state, and a higher arson rate. We conclude by discussing the implications of these findings for future research and public policy. 相似文献
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The hypothesis that irritability and contingency detection are negatively correlated was examined in thirty‐one 6‐month‐old infants. Observation and maternal report‐based assessments of irritability were correlated with both a criterion score and a continuous score of contingency detection. Results indicated that greater irritability in infants was associated with lower contingency detection scores. Discussion focuses on identifying processes by which the 2 constructs may be associated. 相似文献
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Martin D. Ruck Michele Peterson‐Badali David M. Day 《Journal of research on adolescence》2002,12(3):373-398
Adolescents' and mothers' understanding of children's self‐determination and nurturance rights was examined in the context of the home. In individual interviews, 141 sixth, eighth, and tenth graders and their mothers responded to hypothetical vignettes in which a child story character wished to exercise a right that conflicted with parental practices. For each vignette, participants were asked to judge whether the story character should have the right in question and to provide a justification for their decision. Generally, eighth and tenth graders were more likely than their mothers to endorse requests for self‐determination and less likely than their mothers to support requests for nurturance. Mothers of tenth graders were more likely to support requests for self‐determination and less likely to favor adolescents' request for nurturance in the home than were mothers of sixth and eighth graders. In terms of reasoning, adolescents and mothers were more likely to consider the individuals' rights when discussing self‐determination situations, whereas nurturance situations elicited responses pertaining to participants' understanding of familial roles and relationships. Furthermore, mothers' reasoning about childrenà s rights reflected sensitivity to the developmental level of their children. The findings are discussed in terms of previous research on the development of children's understanding of rights and adolescent autonomy. 相似文献
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本文报道了在LRH-250E型培养箱中对平均尾重0.2g和1.2g的虎鲨进行温度耐受性试验,并对均重1.2g的虎鲨做了pH耐受性研究。结果表明:尾重O.2g的虎鲨在驯化温度为20℃时,水温突变引起的致死高温为41℃,致死低温为14℃;尾重1.2g虎鲨在驯化温度为24℃时,水温突变引起的致死高温是42℃,致死低温为14.5℃。尾重1.2g虎鲨能够耐受的pH值其上限是11.51,下限是2.52。 相似文献
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张玉柯 《河北大学学报(哲学社会科学版)》2002,27(2):91-95
建立一个调整世界各国贸易关系的组织 ,以便在比较宽松的环境下开展国际贸易 ,是世界各国的共同愿望。经过战后近半个世纪的艰苦努力 ,从GATT到WTO ,在循序渐进的过程中 ,形成了当今比较完整的国际贸易体系 相似文献