土地利用规划的生态风险分析

本文通过对土地利用及土地利用规划基本特性分析,提出土地利用规划生态风险源的五个方面,即土地利用规划的预测性、实施的长期性、决策主观性、土地利用的低可逆性、土地资源的系统性,描述了土地利用规划生态风险的主要表征:诱发泥石流或其发生频率增加、水土流失加剧、人居环境恶化、森林覆盖率降低、气候异常变化。     

A characterization of the gamma process by conditional moments

Summary The gamma process is determined by the form of conditional expectations and conditional variances. Also a new characterization of the gamma law is obtained and then applied to characterize the gamma process among the processes with independent increments.     

钒改性催化剂的制备及表征

为了提高废水处理的效果,文章以高岭土为载体,制备了负载型的钒改性高岭土催化剂,并通过X射线单晶衍射、傅立叶红外光谱、扫描电子显微镜等手段对催化剂进行了表征,结果表明:高岭土经改性后,高岭土中的Al-O八面体结构部分被破坏,导致结构无序化,高岭土的层间距和比表面积显著增大,改性后的催化剂负载铁离子时催化效果较好。     

马克思主义中国化学科的基本问题及体系构建

马克思主义中国化不断实现由实践形态向理论形态的提升和发展,构成了马克思主义中国化学科的基本问题;这一基本问题具体体现在宏观学科建设、学科内容建设和学科方法建设等三个层次;这些层次的具体展开为马克思主义中国化学科体系的构建奠定了客观基础。     

5-乙酰基-2-氨基-4-甲基噻吩-3-甲酸乙酯的合成、表征及荧光性能研究

用乙酰丙酮、氰乙酸乙酯和硫粉为原料在三乙胺的作用下合成了5-乙酰基-2-氨基-4-甲基噻吩-3-甲酸乙酯,通过元素分析、核磁对其结构进行表征,并对其荧光性能进行了初步测试,对反应机理和反应条件进行了讨论。     

Proposal of a model to measure competitiveness through factor analysis

This article presents a proposal for a simultaneous competitiveness measurement model for the three geographical levels: country, states, and municipalities. For this, a multivariate factor analysis method is used to help identify five factors, seven sub-factors, and thirty variables, which will be used for the measurement and to present the results of an empirical study on eleven entities: the country, the State of Sonora, and nine municipalities, which represent 80% of the population and 80% of their TGP. The results indicate that, in 2010, the municipality of Hermosillo was the most competitive.     

Multivariate distributions characterized by a relationship between mean residual life and hazard rate

In this paper, we characterize some multivariate distributions based on a relationship between the multivariate hazard rate, as defined by Johnson and Kotz (1975) and Marshall (1975), and the multivariate mean residual life as defined by Arnold and Zahedi (1988). The results are extensions of the results obtained earlier by Roy (1989, 1990) and Ma (1996, 1997). Received July 1997     

现代服务业/制造业的发展与产品服务化的关系

产品服务化成为许多跨国制造企业新的经营策略,从单纯提供有形产品扩展到基于有形产品的增值服务,有形产品本身甚至只作为传送服务的媒介或平台,该现象将从现在的中间产品(即企业投入品)为主向最终消费品领域扩散,从大件耐用消费品向一般消费品延伸,客户从以企业为主转向消费者为主,成为服务业和经济发展的主要动力来源。     

基于灰关联分析的常州市物流需求表征量选择

在进行物流需求预测时,选择正确的物流需求表征量尤为重要,它将直接影响预测的精度。本文利用灰关联分析法对常州市物流需求表征量进行建模分析,最终选取货运量来表征常州市物流需求水平。     

磁性淀粉的制备及表征

本试验利用玉米淀粉制备了具有特殊性能的磁性淀粉,并利用X-衍射对所制备的磁性淀粉进行了表征。得出磁性淀粉的最佳合成条件为：氯化亚铁用量250ml,pH11,反应时间120min,搅拌速率400r/min。通过X-衍射的分析表明,在此条件下制备的磁性淀粉具有良好的性能。