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111.
高校物流实验室建设探析 总被引:2,自引:0,他引:2
分析了高校建设物流实验室的必要性和总体目标,对物流实验室实训方案设计的基本思路、具体实训课程计划等问题进行了探讨,总结了高校物流实验室建设存在的误区和需要注意的问题。 相似文献
112.
近10年来,全国高等职业教育得到了大力推进和快速发展,已占据高等教育的半壁江山。要搞好高职教育,应对高职教育的对象即高职学生情况进行分析研究,了解其特点,因材施教,特别应注重学生实践能力的培养,这样才能更有针对性的进行教育培养工作,使高职教育培养的学生能真正成为社会所需要的人才。 相似文献
113.
高许 《科技情报开发与经济》2009,19(17):225-227
从矿井中瓦斯存在的形式、瓦斯涌出条件及瓦斯涌出措施等方面入手,通过案例分析说明了砌筑通风设施位王的合理性在防治瓦斯方面的重要性. 相似文献
114.
Physicochemical and Graph Theoretical Descriptors in Developmental Toxicity SAR: A Comparative Study
O. T. Macina N. B. Sussman H. G. Claycamp S. G. Grant 《SAR and QSAR in environmental research》2013,24(5-6):345-362
Abstract Chemical insults to the developing fetus can lead to growth retardation, malformation, death, and functional deficits. The present study seeks to determine if physicochemical and/or graph theoretical parameters can be used to determine a structure-activity relationship (SAR) for developmental toxicity, and if consistency is observed among the selected features. The biological data utilized consists of a diverse series of compounds evaluated within the Chernoff-Kavlock in vivo mouse assay. Physicochemical parameters calculated correspond to electronic, steric, and transport properties. Graph theoretical parameters calculated include the simple, valence, and kappa indices. Both sets of parameters were independently applied to derive SARs in order to compare the quality of the respective models. Multiple random sampling, without replacement, was utilized to obtain ten training/test partitions. Models were built by linear discriminant analysis, decision trees, and neural networks respectively. Comparisons on identical sets of data were carried out to determine if any of the model building procedures had a significant advantage in terms of predictive performance. Furthermore, comparison of the features selected within and across the model building processes led to the determination of model consistency. Our results indicate that consistent features related to developmental toxicity are observed and that both physicochemical and graph theoretical parameters have equal utility. 相似文献
115.
116.
Wan K. Jo Jong H. Lee 《International journal of environmental analytical chemistry》2013,93(15):1412-1424
A lesser degree of information is available with respect to microenvironments associated with potential exposure to naphthalene, in comparison with other volatile organic compounds. The current study investigated the levels of benzene as well as naphthalene, both in the indoor and outdoor air of apartments and in the cabins of passenger cars. Two groups of 20 apartment buildings (20 new and 20 old) were chosen on the basis of the selection criteria (apartment location and size). In addition, 10 actual commuters were recruited for this study. The equal number of drivers was recruited for the study for comparison of two types of fuels for vehicles (five drivers of gasoline-fuelled and five drivers of diesel-fuelled passenger cars). Indoor naphthalene concentrations were similar between old and new apartments, while the benzene concentrations in new apartments were significantly higher than those of old apartments. The naphthalene concentrations in bedrooms, where wardrobes with moth repellent (MRs) were placed, were significantly higher than those for living rooms where no MRs were present. In turn, these indoor concentrations were significantly higher than outdoor levels. It is noteworthy that the mean and median values of naphthalene measured in the bedrooms exceeded the USEPA RfC (inhalation reference concentration) of 3?µg?m?3, and the living room values were close to the RfC, while the residential benzene levels exceeded the European benzene limit of 5?µg?m?3. In contrast, the maximum outdoor levels were well below that of the RfC. The use of passenger cars appeared to be a significant daily activity for both naphthalene and benzene exposure. The naphthalene-to-benzene ratios varied with the type of microenvironments. Both the indoor naphthalene and benzene concentrations in the present study were much higher than those of other studies. 相似文献
117.
本文综述了有机杂化锑基主族异金属硫属化物的研究进展,对它们的结构和异金属次级结构基元进行了描述、归类和总结;探讨了有机组分分别作为结构导向剂和配体两种角色所起到的不同作用;介绍了这类化合物在离子交换、光催化性能方面的研究;展望了该体系的发展趋势。 相似文献
118.
本文综述了有机杂化锑基主族异金属硫属化物的研究进展, 对它们的结构和异金属次级结构基元进行了描述、归类和总结;探讨了有机组分分别作为结构导向剂和配体两种角色所起到的不同作用;介绍了这类化合物在离子交换、光催化性能方面的研究;展望了该体系的发展趋势。 相似文献
119.
建设社会主义新农村既是一个涉及到经济、政治、文化和社会建设等方面的系统工程,又是一个包含着理念、战略和实践等多重规定在内的综合课题。有必要对涉及社会主义新农村建设的价值取向、个性特征和主体选择等根本性问题进行理性分析,从目标与目的的关系、共性与个性的关系、内容与形式的关系、主导与主体的关系、阶段与过程的关系等方面进行深入的辩证思考。 相似文献
120.
宁波市北仑区普通建筑石料矿产资源开发利用研究 总被引:1,自引:0,他引:1
谢立刚 《长春工程学院学报(自然科学版)》2007,8(1):49-52
针对宁波市北仑区矿产资源规划实施过程中存在的问题展开调查,调查包括议定方案、矿山实地调查、了解市场需求、综合分析资料。并对各种有待完善和需要调整、补充的问题提出应采取的对策和可操作性的建议。 相似文献