汉江流域上游作物水分生态适应性研究

采用农田水量平衡模型,结合GIS技术,通过构建作物水分亏缺风险指数,对汉江流域上游区小麦、玉米等主要作物的水分生态适应性进行了系统研究。结果表明：就全生育期而言,自然降水不能满足作物生长发育的需求,水分亏缺是汉江流域上游区农田水分平衡的主要特征;就不同作物来讲,水稻多年平均水分亏缺风险指数达23.26%,是全流域生态适应性最差的作物,麻类、薯类生态适应性较强;作物生长发育不同时段,各作物水分生态适应性差异较大,春旱应引起足够重视。     

自然灾害风险分析的时空尺度初探

自然灾害风险存在着显著的动态特性,即灾害风险会随时间与空间的变化而呈现出差异。研究自然灾害风险的时空差异是对自然灾害风险研究的进一步深化。其中,时空差异研究的一个重要前提条件是选择恰当的灾害风险分析的时空尺度。广度与粒度是时空尺度的两个孪生指标,时空广度限定了灾害风险评估在时间和空间上的有效范围,而时空粒度则是量度灾害风险时间和空间差异的最小单元。列出了风险时空差异的表达式,深入探讨自然灾害风险的时空尺度,并对我国三种典型的自然灾害(地震、洪涝和台风)风险分析的时空尺度选择进行了讨论,为进一步深入开展自然灾害风险时空差异分析奠定了基础。     

The use (and abuse) of the new environmental paradigm scale over the last 30 years: A meta-analysis

This paper reports a meta-analysis of studies using the New Environmental Paradigm (NEP) Scale over the last 30 years. A review of 69 studies from 36 countries (including 58,279 participants from 139 samples) shows that there is considerable variation in the way the NEP Scale is used, particularly with regards to the number of items used and the number of points on the Likert scale employed. Results from weighted regression analyses reveals that variations in sample type and scale length have a significant effect on NEP scores. In particular, environmentalist and white-collar samples scored significantly higher on the NEP Scale than nationally or regionally representative samples, while blue-collar samples scored significantly lower; and participants scored higher on 6-item versions of the scale than on the revised 15-item version, and lower on versions of the scale containing 5, 7, 8 or 10 items. Implications of this research for the comparability of previous studies using the NEP Scale are discussed and guidelines for future research are presented.     

流域土地利用变化的水质响应研究进展

探讨流域土地利用变化的水质响应,有利于从源头上控制水污染。不同学者在多种边界条件下研究了流域土地利用变化的水质响应,发现流域土地利用变化是造成河流水质发生变化的重要原因。根据是否可以将土地利用活动概化为点状,流域土地利用变化的水质响应研究可分为点状土地利用的水质响应和非点状土地利用的水质响应。准确边界土地利用的水质响应一般是研究流域土地利用空间特征和土地利用结构与水质变化的关系。对于用全流域尺度还是用缓冲区的尺度分析土地利用的水质响应更准确仍存在争论。水域边缘几何形状影响了土地利用与水质的关系。     

不锈钢酸洗过程中NOx的产生机制及控制

为降低奥氏体不锈钢混酸(HNO_3+HF)酸洗过程中产生的NO_x量,利用自制的酸洗-吸收装置研究了HNO_3和HF质量浓度及抑制剂和促进剂加入量对NO_x生成量的影响,探讨了NO_x的产生机制。结果表明,奥氏体不锈钢酸洗的优化工艺条件为:酸洗温度20～50℃,HNO_3质量浓度90～110 g/L,HF质量浓度40 g/L,抑制剂加入量30 g/L,促进剂加入量1～2 g/L。抑制剂的加入降低了NO_x的生成量,促进剂的加入减少了氧化皮酸洗时间,提高了酸洗效率。酸洗产生的NO_x来源于两部分:一是氧化皮与酸洗液反应,约占NO_x生成量的70%,二是裸露基体与酸洗液反应,约占NO_x生成量的30%。     

沸石强化A/O生物脱氮工艺氨氮去除机理研究

沸石强化A/O生物脱氮实验研究表明,沸石对配水氨氮具有良好的吸附性能,其吸附特征可以通过Frend lich和Langmu ir吸附等温线表征,但对污水中氨氮的吸附较配水吸附要复杂。由于沸石能与微生物构成沸石-生物复合体,从而增加了系统的硝化细菌和反硝化细菌数量,改善了A段的反硝化作用和O段的硝化作用。吸附饱和的铵沸石在硝化细菌和电导率的协同作用下,经好氧曝气4.5 h,能再生69.8%。在A段,进水氨氮浓度较高,沸石吸附氨氮,提高污水碳氮比,促进生物反硝化;进入O段,在盐度和微生物的协同作用下,混合液氨氮浓度因为生物降解而逐渐降低,不断打破铵沸石的吸附-脱附平衡,铵沸石不断释放氨氮而得到充分的再生。     

Radiological hazards of TENORM in the wasted petroleum pipes

Disposal petroleum pipes containing sludge and scale as a technically enhanced natural occurring radioactive material (TENORM) leads to internal and external radiation hazards and then a significant radiation dose to the workers. In order to contribute to a future waste management policy related to the presence of TENORM in the disposal sites of wasted petroleum pipes, scale and sludge as TENORM wastes are collected form these disposal pipes for radiometric analysis. These pipes are imported from onshore oilfields at south Sinai governorate, Egypt. The highest mean ²²⁶Ra and ²²⁸Ra concentrations of 519 and 50 kBq/kg respectively, were measured in scale samples. Sludge lies within the normal range of radium concentration. The average absorbed dose caused by the exposure to the wasted pipes equal to 4.09 μGy h⁻¹ from sludge and 262 μGy h⁻¹ from scale. This is much higher than the acceptable level of 0.059 μGy h⁻¹. Due to radon inhalation, important radon related parameters are calculated which advantage in internal dose calculation. Fairly good correlation between real radium content and radon exhalation rate for sludge samples is obtained. The hazards from sludge come from its high emanation power for radon which equal to 3.83%. The obtained results demonstrate the need of screening oil residues for their radionuclide content in order to decide about their final disposal.     

基于集约评价的城市开发区规模计量研究——以南京市省级以上开发区为例

随着开发区集约利用评价工作的全面开展,合理界定其用地规模成为研究的重点。本文以南京市为例,首先运用多目标决策法评价开发区集约利用等级,然后采用逐步回归法选取与集约利用相关度较大的因素作为预测依据,进而计量其合理的规模。研究结果表明:其一,A、B和C开发区集约等级为II级,可以适当扩大开发区规模;D、E、F和G开发区集约等级为III级,应该维持开发区规模;而H和I开发区集约等级为IV级,应适当缩小开发区规模。其二,当B开发区、A开发区和其他开发区地均工业总产值增长率分别达到23.10%、18.18%和15%时,可以充分发挥土地利用潜力。其三,即使实现土地集约利用,B开发区仍需扩充6.08 km2。最后,本文提出通过科学设定地均工业总产值增长率来提升开发区集约利用水平的政策建议。     

Approach of technical decision-making by element flow analysis and Monte-Carlo simulation of municipal solid waste stream

This paper deals with the procedure and methodology which can be used to select the optimal treatment and disposal technology of municipal solid waste （MSW）, and to provide practical and effective technical support to policy-making, on the basis of study on solid waste management status and development trend in China and abroad. Focusing on various treatment and disposal technologies and processes of MSW, this study established a Monte-Carlo mathematical model of cost minimization for MSW handling subjected to environmental constraints. A new method of element stream （such as C, H, O, N, S） analysis in combination with economic stream analysis of MSW was developed. By following the streams of different treatment processes consisting of various techniques from generation, separation, transfer, transport, treatment, recycling and disposal of the wastes, the element constitution as well as its economic distribution in terms of possibility functions was identified. Every technique step was evaluated economically. The Mont-Carlo method was then conducted for model calibration. Sensitivity analysis was also carried out to identify the most sensitive factors. Model calibration indicated that landfill with power generation of landfill gas was economically the optimal technology at the present stage under the condition of more than 58% of C, H, O, N, S going to landfill. Whether or not to generate electricity was the most sensitive factor. If landfilling cost increases, MSW separation treatment was recommended by screening first followed with incinerating partially and composting partially with residue landfilling. The possibility of incineration model selection as the optimal technology was affected by the city scale. For big cities and metropolitans with large MSW generation, possibility for constructing large-scale incineration facilities increases, whereas, for middle and small cities, the effectiveness of incinerating waste decreases.     

氙灯曝露试验中标准物质的用途及使用方法

本文介绍了氙灯曝露试验中应用的主要标准物质,它们的用途及使用方法,着重介绍了蓝色羊毛标准、聚苯乙烯标准塑料片的应用.