地下水污染修复的活性渗滤墙技术

活性渗滤墙是一种现场修复受污染地下水的新型技术，具有原理简单，施工方便，运行费用低廉等特点，活性渗滤墙垂直于地下水流动方向设置，当地下水流通过活性渗滤墙时，污染物与墙体材料发生化学反应，从而达到环境修复的目的。文中综述了活性渗滤墙技术的修复机理和实际应用，大量研究表明，应用金属铁作为活性渗滤墙材料，可以去除地下水中的重金属以及有机污染物，目前活性渗滤墙已经在世界各地应用，是一种非常有发展前景的环境污染修复技术。     

Predicting Youth Access to Tobacco: The Role of Youth Versus Store-Clerk Behavior and Issues of Ecological Validity.

Twenty-one 15- to 17-year-olds attempted to purchase cigarettes in 232 stores in the manner that confederates typically do in access studies, as well as in the manipulative ways (e.g., lying about their ages) that youth smokers do, thereby modeling youth access to tobacco within versus outside of studies, respectively. Youth typical-research versus manipulative behavior was contrasted with clerk behavior (requests for youth ID cards) to examine the relative contributions of both to youth access to tobacco for the 1st time. Results revealed that clerk behavior was the strongest predictor of cigarette sales to youth and hence underscore the need for interventions with merchants. Sales nonetheless were higher under youth-manipulative conditions and thereby highlight the low ecological validity of access research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Simulation of Economic Dynamics under Ecological Balance Conditions

A model of economic dynamics under stable ecological balance conditions is proposed. A methodology of construction of an optimal growth path is constructed for this model.     

山前平原地下水侧向补给潜力空间变异模拟

SWAT模型利用分辨率较高的DEM数据,可以估算山前地下水侧向补给的空间变异,并可以计算不同降水年型下补给量的差别。模拟需要对研究区进行填洼、流向确定、汇流和河网水系的提取四步运算,并对河道临界支撑面积的取值进行分析。分别模拟了平水年和丰水年两种降雨年型下研究区13个出水口的地下水侧向补给潜力。在研究区,由于地形的变化,导致山与平原交接断面上出水口的集水面积变异非常大,因此山前平原所接受的地下水侧向补给量的空间变异也非常大。不同的降雨年型下,降雨量转化为地下水侧向补给量的比例也不同。平水年的转化比例较小,丰水年的转化比例较大。应用SWAT模型时,与ArcView的拓展模块有机结合,可以更方便提取完整的大流域,划分出合理的子流域。     

生态环境的规划设计

本文论述了生态环境规划设计的基本理论、以生态理论为指导,提出了营造生态环境的几种方法。     

Wave drift force in a two-layer fluid of finite depth

Based on the momentum and energy conservation principles, a compact calculation formula is analytically derived for the wave-drift force on a 2-D body floating in a two-layer fluid of finite depth. In a two-layer fluid, two different wave modes (the surface-wave mode with longer wavelength and the internal-wave mode with shorter wavelength) exist not only in the incident wave but also in the body-scattered wave, and these wave characteristics are properly incorporated in the obtained formula. It is noted that, unlike the single-layer case, the wave-drift force can be negative in the incident wave of surface-wave mode, if the transmitted wave with internal-wave mode is large. Numerical computations are implemented for a Lewis-form body by means of the boundary-integral-equation method with Green’s function for the two-layer fluid problem. The effects of density ratio, interface position, and body motions on the wave-drift force are studied, and some important features are found for two-layer fluids.     

Evaluating reactivity to ecological momentary assessment during smoking cessation.

Ecological momentary assessment (EMA) consists of assessing phenomena in real time in the natural environment. EMA allows for more fine-grained analyses of addictive behavior and minimizes threats to internal validity, such as recall biases and errors. However, because of the intensive monitoring involved in EMA, measurement reactivity is a concern. To test whether EMA with palmtop personal computers induces reactivity, the authors compared smoking-related outcomes between smokers using EMA and those not using EMA during a quit attempt. The use of no-EMA control groups has been rare in reactivity investigations to date. The EMA protocol included event-contingent assessments (smoking episodes, urge episodes) and random assessments. Outcomes included biologically confirmed abstinence and self-report measures of withdrawal, self-efficacy, motivation, affect, and temptations. Participants were smokers motivated to quit (N = 96). They were randomized to 1 of 3 groups: EMA for the week preceding a planned quit date, EMA for the week following the quit date, and no EMA. Abstinence rates did not differ between the groups at Day 7 or at Day 28 postcessation. For the 20 subscales assessed at each of 3 assessment times, there were significant differences between participants with and without EMA experience for 3 subscales at the 1st of 3 assessment times, and significant differences for 3 different subscales at the 3rd assessment time. These differences suggest some reactivity to EMA, although the inconsistent pattern across time indicates that further research is needed to definitively conclude that EMA induces reactivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

叠前深度偏移中的旅行时并行计算技术

旅行时计算技术是基于波动方程叠前深度偏移方法的核心内容，射线跟踪的数值计算精度和效率直接影响着介质成像质量和实用化。基于三维射线跟踪的微变网络方法和波前重建思路，提出一种适用于三维复杂介质地震波走时的快速算法。但它所需计算量巨大。采用并行计算技术，设计出基于“任务缓冲池”的动态负载平衡策略，在现有的分布式计算机上，实现了三维射线追踪和叠前深度偏移的并行计算。     

生态公路概念浅析

通过对生态公路概念的分析,深入剖析了生态公路的内涵,总结了生态公路的特征,从宏观上科学地把握了生态公路的思想精髓,从而进行总结,为生态公路的进一步发展奠定了理论基础。