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991.
鞍钢铁水脱硫扒渣发展综述   总被引:1,自引:0,他引:1  
为了满足生产低硫高附加值产品的需要,铁水预处理作为钢铁冶金生产工艺的一个重要手段,越来越得到业内人士的认同,特别是铁水炉外脱硫扒渣近年来发展较快。介绍鞍钢铁水脱硫扒渣发展的3个阶段及扒渣工艺设备的优化与改进情况;对国产脱硫工艺设备、美国ESM复合喷粉脱硫工艺设备以及德国POLYSUIS复合喷粉脱硫工艺进行了全面的对比分析。鞍钢铁水脱硫扒渣发展过程充分实践了鞍钢“高起点、少投入、快产出、高效益”的技改方针。  相似文献   
992.
从行业分析法入手,分析了高职机械专业群必须具备的一般能力、专业基础能力和专业技术能力和应具备的八个方面的知识,从而设计出机械专业群能力、知识和素质结构图,完成课程开发中的课程分析和课程设计工作。  相似文献   
993.
介绍了日标对SD390的要求及其开发过程。  相似文献   
994.
从分析化学的研究对象、发展规律入手,展望新世纪分析化学更加辉煌的发展。  相似文献   
995.
Increasing complexity of many constructed facilities and escalating demands for project performance are driving significant changes in design and construction. Increased project integration and technical support of construction operations provide a promising response to these demands. This paper identifies and describes nine critical activities to increase technical support for construction: integrate early planning; plan for regulatory compliance; consider construction methods and sequences in design; tailor and time technical information to users’ needs; provide materials to support effective construction; identify and provide construction-applied resources; create an environment for safe, productive, and high quality work; technically support efficient construction operations and completion; and transfer experience between projects. The paper’s relevance to industry practitioners includes multiple benefits of completing these activities for firms, projects, and professionals, along with the necessary steps to develop this capability and gain these benefits. Educators and researchers can use the activities to structure course topics related to technical fundamentals of construction and integration with design, along with future investigations of construction process knowledge.  相似文献   
996.
Community involvement is an important factor for sustainable highway construction. Information and communication technologies provide a new and more effective approach to facilitate community involvement. However, there are too many parameters with conflicting and subjective definitions related to sustainability and too many stakeholders with varying degrees of interest and sophistication. There is a need for an effective tool to communicate project impacts on sustainability to local communities. This paper presents an ontology for stakeholder management and sustainability in highway construction. An ontology is a conceptual semantic model that attempts to capture human knowledge (both explicit and tacit) in a consistent manner. Ontologies include three main elements: a taxonomy (common vocabulary presented in concept trees), set of relationships (linking concepts across trees), and axioms (limitation/constraints on the behavior of concepts). The ontology was used to develop a portal for broadcasting highway design features to local communities. By browsing through the portal, a user can learn about project elements, the impacts of each element on sustainability issues, who is sponsoring such element, and what efforts have been made to reduce any impacts of such elements on local communities.  相似文献   
997.
The effects of serotonergic agonists were examined in intact and spinal fetuses, using an in vivo fetal rat preparation. On Gestational Day 20, fetuses were prepared with a midthoracic or sham spinal transection. Dose-response curves were obtained for quipazine (nonselective 5-hydroxytryptamine [5-HT] agonist; 1.0-10.0 mg/kg), CGS-12066A (5-HT1B agonist; 1.0-30.0 mg/kg), and α-methylserotonin (α-Me-5-HT; 5-HT? agonist; 0.2-15.0 mg/kg). During a 10-min test, each of the agonists (delivered via intraperitoneal injection) influenced fetal behavior: They increased the occurrence of head movements, mouthing, and hindlimb stepping. Quipazine and α-Me-5-HT also promoted hindlimb activity in spinal fetuses. Thus, stimulation of the fetal 5-HT system modulates motor activity at multiple levels of the developing central nervous system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
Despite anecdotal evidence suggesting that air travel is personally demanding, little research has examined air travel stress. To address these issues, the author developed and evaluated the 1st known measure of air travel stress--the Air Travel Stress Scale--in 3 studies. Exploratory and confirmatory factor analysis indicated 3 components: (a) anxious reactions to adverse air travel events, (b) angry reactions to other passengers as well as an antecedent of air travel stress, and (c) the lack of trust that the airlines/airports will ensure one's comfort and safety. Each component had good internal reliability and test-retest reliability over a 6- to 7-week interval. Each component showed evidence for discriminant and convergent validity. Implications for research into understanding and intervening on air travel stress are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
999.
This study adds to the growing literature linking children's experiences in the environment to individual differences in their developing skills in attention, memory, and planning. The authors asked about the extent to which stimulating and sensitive care in the family and in the child-care or school environments would predict these cognitive outcomes. The authors also questioned the primacy of experiences in the first 3 years of life. Data from a sample of 700 first graders whose experiences in the home and in child care or school were evaluated since early infancy revealed that the cumulative quality of the child-rearing environment was related to attention and memory but not to planning and that the quality of the family environment was more strongly associated with outcomes than was the quality of child care and of school. The quality of both children's early (6 through 36 months) and later (54 months and first grade) environments predicted performance on the attention and memory tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
Early Head Start, a federal program begun in 1995 for low-income pregnant women and families with infants and toddlers, was evaluated through a randomized trial of 3,001 families in 17 programs. Interviews with primary caregivers, child assessments, and observations of parent-child interactions were completed when children were 3 years old. Caregivers were diverse in race-ethnicity, language, and other characteristics. Regression-adjusted impact analyses showed that 3-year-old program children performed better than did control children in cognitive and language development, displayed higher emotional engagement of the parent and sustained attention with play objects, and were lower in aggressive behavior. Compared with controls, Early Head Start parents were more emotionally supportive, provided more language and learning stimulation, read to their children more, and spanked less. The strongest and most numerous impacts were for programs that offered a mix of home-visiting and center-based services and that fully implemented the performance standards early. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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