关于培养学生环境意识的思考

环境问题作为人类面临的共同挑战，日益为国际社会广泛关注。开展环境教育，普及环境科学知识，提高人们的环境意识，是解决环境问题最基本，最有效的措施，如何认识和进行环境教育是广大教育工作应该给予关注的重大课题，笔对其中的几个问题，诸如环境意识、环境教育的目的和方法等进行了研究和探讨，提出了自己的观点和建议。     

加强高校德育工作必须处理好的几个关系

从摆正立足点、调动积极性、优化育人环境、发挥主渠道作用等几个方面论述了加强高校德育工作必须处理好的几个关系     

碳纤维复合材料(CFRP)约束矩形截面混凝土柱应力-应变关系研究

现有对于CFRP约束混凝土圆柱的应力-应变关系的研究已经开展得较为广泛，但对于实际中存在更多的矩形柱而言，其相关研究却非常有限。本文对14根碳纤维（CFRP）约束矩形截面混凝土柱进行了轴压试验，分析了试验现象和受力机理，研究了圆角半径，截面长宽比、外包纤维量对承载性能的影响，给出了试验结果，并基于试验数据验证了Lamand Teng（2003）提出的面向设计的纤维约束混凝土矩形柱应力-应变模型，所得的计算值与试验结果基本吻合，证明了该模型的可靠性，能够满足设计要求。     

型钢-方钢管混凝土轴压荷载-变形关系曲线的计算

在合理选择钢材和核心混凝土的本构关系模型的基础上,利用通用有限元软件ABAQUS对型钢-方铜管混凝土轴压荷载-变形关系曲线进行计算,计算曲线与试验曲线吻合较好,在此研究结果的基础上,可利用ABAQUS对型铜-方钢管混凝土轴压工作机理进行较为深入的研究.研究成果可为相关研究提供参考.     

我国城乡发展的“刘易斯转折点”辨析及延伸探讨——基于湖北省村镇调研的城乡二元关系研究

日益严峻的"民工荒"现象引发了我国是否已出现所谓"刘易斯转折点"的讨论。刘易斯二元经济模型将"城市—乡村"的发展看成一个交互的连续过程,而我国独特的城乡二元体制和显著的区域差异则导致了该理论分析上的诸多困惑。文章在厘清刘易斯模型的各种预设条件及其与中国现实差异的基础上,对相关研究进行归纳和述评;然后以湖北省村镇调研为例,从城镇化的微观机制视角检验相关研究的主要观点及政策建议。最后,文章试图为中国特色的"二元关系转折点"现象提供解释框架,并基于微观机制研究的启示而讨论其政策含义。     

The Bacterial Quality of an Upland Stream

Faecal coliform concentrations were determined at stream and water inflow sampling sites within an upland catchment in North Derbyshire containing rough, semiimproved and improved pastures. The results indicated that, during its passage through the catchment, the faecal indicators of the stream increased, and this may constitute a health risk to cavers using a popular recreational cave into which the stream drains. The decline in streamwater quality suggests that a semipermanent store of bacteria existed in catchment soils, and hydrological processes operated to transfer bacteria from the land to the stream channel. Contrary to expectations, intra-catchment differences in the bacterial quality of water at inflow and stream sampling sites could not be related to the intensity of agricultural land use in adjacent areas. This is explained with reference to changes in the nature of hydrological transport pathways associated with the improvement of pastures.     

DYNAMICS OF SEDIMENT-ASSOCIATED METALS IN A HIGHLY URBANISED CATCHMENT: BRADFORD, WEST YORKSHIRE

Urban watercourses are potential hazards because of their rapid flow changes, poor water quality and contaminated sediments. This study is a preliminary field investigation into fine sediment-associated metal contamination and its transport dynamics in a highly urbanised catchment in West Yorkshire, UK. Spatial and temporal changes in the concentration of channel-bed sediment-associated metals are investigated, and the fluxes of selected suspended sediment-associated metals, during an extreme high flow event, are determined. Channel-bed sediments were more contaminated at the most heavily urbanised sites. Data suggest that contaminated bed sediments could accumulate and possibly become increasingly contaminated between high-flow events, prior to being flushed from the system. Fluxes of contaminated suspended sediments were very high at the peak of the high flow event. The spatial and temporal dynamics of contaminated fine sediment which were identified in this study could inform planners with regard to future monitoring strategies.     

同位素测年新发展:~(81)Kr测定古老地下水年龄理论

自从1966年Loosli&Oeschchger测定出大气中的81Kr,就已经有人设想放射性81Kr(半衰期为(2.29±0.11)×105年)可能成为测定古老地下水年龄(105~106年)的有效工具。但一直没有付诸实践,直到2000年,Collon等人首次利用81Kr同位素确定澳大利亚大自流盆地(GAB)的古老地下水年龄。本篇文章中主要介绍了影响81Kr同位素测年的因素,81Kr的取样制样分析过程,回旋加速质谱仪分析81Kr同位素的原理。     

我国城市房地产评价因素选取研究

介绍了城市房地产发展评价因素选取的原则,对城市房地产发展评价选取的因素进行了研究,构建了影响房地产发展因素的体系并对影响房地产发展的相关指标进行了分析,进而促进房地产的发展。