成渝产业带产业结构的相似性及其结构转换力分析

利用数据方差,相关系数和相似系数指标对成渝产业带这一长江上游具有重要地位的经济区域进行了产业和结构特征分析。从产业部门相对变动的总体方差看,第一产业在国内生产总值中的份额变动幅度最大,即第一产业在国内生产总值的比重元首衡性最弱,第三产业次之,第二产业最小;     

博乐市PM10与TSP相关性分析

选用博乐市2010年大气PM10与TSP监测数据月均值,分析了PM10与TSP在大气中的浓度变化相关性趋势、沙尘暴天气对其相关性的影响以及PM10占TSP中的浓度比,并得出PM10与TSP的浓度变化趋势除沙尘暴天气干扰外非常相似,具有很好的相关性。     

山东省生态环境质量现状及动态变化研究

以2005年和2009年美国陆地卫星(Landsat TM)影像为基本数据源,利用遥感与GIS技术对山东省生态环境状况进行了监测,并依据《生态环境状况评价技术规范(试行)》(HJT 192-2006),对山东省生态环境质量现状及动态变化趋势进行了评价。结果表明,山东省生态环境质量总体处于一般水平;2005—2009年山东省生态环境质量状况基本稳定,局部地区有所改善。     

丹江口水库流域氮素时空分布特征

为全面了解丹江口水库流域氮素污染状况,对库区26个点位及10条主要入库河流入库口处的表层水样进行了丰水期、平水期、枯水期采样与监测,探讨了氮素时空分布特征。入库口总氮检出范围为1.31~10.96 mg/L,其中泗河和神定河入库口总氮最高。总氮为库区水质主要限制因子,年均总氮质量浓度为1.13~2.71 mg/L;汉江库区整体上总氮污染水平略高于丹江库区,且与丹江库区相比,汉江库区受点源排放的影响较大。10条入库河流总氮的总年均输入量为63 347.31 t/a,其中汉江的总氮输入量最大;入库河流总氮控制的关键在于溶解性有机氮和硝酸盐氮的控制。     

大跨度偏压隧道受火损伤分析

为探明火灾对大跨度偏压隧道造成的不利影响,依托贵州省某公路隧道工程,基于ANSYS有限元软件分析不同埋深及偏压条件下大跨度隧道结构的最大损伤和相对温度损伤变化规律,并对其温度场分布和应力分布规律进行总结。结果表明:衬砌高温损伤约60 mm,温度影响深度约300 mm,内部温升过程逐渐由曲线变化转变为直线变化;最大损伤深度随偏压角度增加近似呈指数增长变化,而相对温度损伤略有减小,当偏压角度较大时,火灾将成为隧道破坏的诱导因素而非直接因素;最大损伤深度与偏压隧道埋深近似呈抛物线变化,火灾对偏压隧道影响显著,必须采取有效预防措施;随着受火时间的增加,临火侧衬砌混凝土在热膨胀及围岩约束作用下,压应力快速增加,存在较大的压溃风险。     

绿色建筑供应链主导企业结构模型与运行实践分析

建筑可持续发展涉及多主体全过程,实施有效途径是构建绿色建筑供应链,基于绿色供应链理念构建绿色建筑供应链结构模型,分析绿色建筑供应链特点,界定绿色建筑供应链协调运行的主体职责,架构绿色建筑供应链主导企业及其基于主导企业驱动的绿色建筑供应链结构模型,剖析绿色建筑供应链运行实践问题,提出基于主导企业驱动的绿色建筑供应链协调运行的内在要求。     

风致弱振下高层建筑舒适性评价研究

基于结构安全的高层建筑理论计算模型所确定的结构动力特性与实测值往往有较大差别,这会使结构动力响应的计算及风振舒适度的评价产生较大误差。针对此问题,基于风振舒适度评价的目的,考虑填充墙、楼板装饰面层、楼梯和活荷载取值四种精细化模型修正因素,提出了基于舒适度评价的高层建筑精细化计算模型的一般构建方法。通过实测和理论分析对某沿海高层建筑的精细化计算模型进行了研究,对精细化模型的修正因素进行了探讨。结果表明:精细化模型修正因素中填充墙对结构动力特性的影响最大,精细化计算模型的动力特性与实测值更吻合,更准确地反映了结构真实的振动特性。精细化计算模型的研究工作可为此类高层建筑的风振舒适度评价提供借鉴。     

低温环境下桥梁用结构钢疲劳寿命估算方法

在现有研究成果的基础上,基于断裂力学理论提出了适用于桥梁结构钢的低温疲劳寿命估算方法。利用室温环境下的疲劳性能参数和低温环境的基本力学性能参数对低温环境下的疲劳极限、疲劳裂纹扩展门槛值等进行预测,建立疲劳裂纹扩展速率模型,应用等效初始裂纹法估算低温环境下桥梁钢的疲劳寿命,并通过塑性区裂纹尺寸修正进行低周疲劳寿命预测。通过算例表明,该方法能够较为准确的预测Q345qD钢试件的拉伸疲劳寿命,从而避免了成本高昂的低温疲劳试验,为钢结构桥梁的低温疲劳分析提供简便而实用的依据。     

The Role of Organizational Perception,Perceived Consumer Effectiveness and Self-efficacy in Recycling Advocacy Advertising Effectiveness

Previous academic research into how consumers evaluate advocacy advertising identified many possible paths involving potentially reflexive effects on how people perceive an advocacy advertising sponsor, the advocated issue and themselves. This paper has examined one possible scenario within this complicated phenomenon: that of advertising advocating a specific environmental consumer action, recycling. In the specific context of this study, structural equation modelling demonstrated clear causal relationships among consumer perceptions of the recycling advertisements’ sponsoring organization, consumer self-efficacy and perceived consumer effectiveness of complying with the advocated issue (recycling behaviour). These factors were shown to impact specific advocacy advertising goals (termed message effectiveness in this study) such as behavioural intention toward the advocated recycling issue and perceived changes in how consumers evaluate the sponsoring organization.     

Industrial applications of natural fibre-reinforced polymer composites – challenges and opportunities

The growing industrial demand for sustainable materials has led to a paradigm shift in the focus from synthetic polymers towards natural fibres. This paper deals with the challenges and opportunities associated with the use of natural fibre-reinforced polymer composites in various industrial applications. Natural fibres being biodegradable, light in weight, cost-effective and environment friendly are good candidate materials for modern industrial applications. Use of natural fibres in various industries with a focus on automotive and furniture industry has been discussed. The commonly used natural fibres in polymer composites including jute, hemp, sisal, kenaf, bamboo, cotton, flax, abaca, coir etc. have been dealt with in this paper. The literature revealed that tensile strength and other mechanical properties of these fibres are comparable to synthetic fibres like glass or carbon fibres. However, the temperature stability of polymers limits their extensive use and remains an issue to be addressed.