基于主成分—聚类分析的贫困县（区）经济发展研究——以陕南地区国家级贫困县（区）为例

采用国内生产总值、人均纯收入、城镇固定资产投资、社会消费品零售总额等11个指标,运用主成分分析法对陕南地区20个国家级贫困县（区）的经济发展水平进行了评价,在此基础上运用聚类分析法将贫困县（区）分成四种类型：第一类是＂第二、第三产业并进型＂的汉滨区,第二类是＂特色农业带动型＂的商州区,第三类是＂优势矿业驱动型＂的洛南县和旬阳县,第四类是＂传统农业主导型＂的其余16个贫困县,针对各类型贫困县（区）提出相应的发展对策。     

Application of Wavelet Coherence Method to Investigate Karst Spring Discharge Response to Climate Teleconnection Patterns

The impact of climate teleconnections on the regional hydrometeorology has been well studied, but very little effort has been made to relate climate teleconnections with groundwater flow variation. In this study, we used a wavelet coherence method to analyze monthly climate indices, precipitation, and spring discharge data, and investigated the relation between major teleconnection patterns (the Arctic Oscillation, North Atlantic Oscillation, Pacific Decadal Oscillation, El Niño‐Southern Oscillation, and Indian Ocean Dipole) and karst hydrological process in Niangziguan Springs Basin, China. The results indicate precipitation and spring discharges correlate well with climate indices at intra‐ and inter‐annual time scales. Further, the climate indices are mainly correlated with precipitation at shorter periodicities, but correlated with spring discharge at longer scales. The difference reflects the modulation of karst aquifers on precipitation‐spring discharge during the processes of precipitation infiltration into the ground, and subsequent transformation into spring discharge. When teleconnection signals are transmitted into spring discharge via precipitation infiltration and groundwater propagation, some high‐frequency climatic signals are likely to be filtered, attenuated, and delayed, thus only low‐frequency climatic signals are preserved in spring discharge.     

偶氮二甲酰胺发泡剂清洁生产评价模型

提出了针对不同工艺的偶氮二甲酰胺（ADC）发泡剂生产企业的清洁生产综合评价方案。利用逐层序关系分析法确定各指标的影响因子,采用极差标准化法对正逆向指标数据进行初步处理,使用主成分分析法对ADC发泡剂生产企业进行排名。该研究为ADC发泡剂清洁生产评价提供了一个更加客观和精确的方案。     

基于振动传递率的钢框架损伤识别试验研究

提出了基于振动传递率和主元分析相结合的新的损伤识别方法。首先,由结构无损伤时某2个位置的振动传递率样本构成结构的参考总体,以结构损伤状态时相同位置的振动传递率构成待检样本集;其次,把待检样本逐个代入到参考总体中,构成多个原始数据矩阵;然后,对所有原始数据矩阵进行主元分析并构造相应的控制椭圆和T2控制图,以前2阶主元在控制椭圆和T2控制图中的分布来确定结构是否存在损伤;最后,用一钢框架结构试验验证了本文方法的有效性,并引入振动传递率幅值的总体变化来识别结构损伤位置,损伤识别结果显示,此损伤指标能够很好的识别结构单一位置的损伤。     

活性炭柱中砂垫层在微污染水源水处理工艺中的应用

以嘉兴市某水厂沉后水为进水进行实验,研究炭砂滤池对污染物的去除性能,以及炭砂滤池取代活性炭＋砂滤池的可能性,探讨了短流程工艺的适用性。结果表明,炭砂滤池能有效去除水中的浊度、氨氮、CODMn和铁、锰等污染物,与活性炭柱相比,炭砂滤池在降低出水浊度和水中颗粒数方面具有一定优势,即砂垫层对控制出水浊度和保障微生物安全能够起到积极作用。在实验条件下,增加活性炭层厚度或者降低滤速,在一定程度上有利于提高对CODMn的去除率。在设计滤速为9～10 m/h,CODMn〈4.5 mg/L时,可直接以炭砂滤池取代活性炭池＋砂滤池,仍然能保证出水CODMn〈3 mg/L。     

南京城市土壤重金属含量及空间分布特征

研究了南京城市土壤重金属含量、来源及空间分布特征。结果表明,南京城市土壤中V、Mn、Co、Ni、Cr污染不明显,但受到了不同程度的Cu、Pb、Zn、Sb、Hg、Cd污染,其中Hg污染比较严重。V、Mn、Co、Ni、Cr含量之间均呈极显著正相父;Cu、Pb、Zn、Sb、Hg、Cd含量之间也均呈极显著正相关。南京城市土壤V、Mn、Co、Ni、Cr主要继承了原土物质;Hg、Cd、Pb主要来源于城市燃煤、机动车尾气及工厂排放粉尘;Sb主要来源于机动车尾气和工厂排放粉尘。南京城市土壤Hg、Cd、Pb、Sb含量空间分布规律非常相似,均表现为外围向市中心有逐渐增加的趋势,并且在新街口—鼓楼、梅山硫铁矿形成异常高值的岛状、环状区域。     

基于主成分分析法的长江经济带省会城市水生态文明评价

城市水生态文明评价指标体系是测量水生态文明,指导城市水生态文明建设的基础。在综述国内水生态文明评价研究文献基础上,按水生态、水经济和水社会三大系统,从水生态、水工程、水经济、水管理和水文化等方面筛选了18项指标构建了水生态文明城市建设平价指标体系,并应用主成分分析法对长江经济带11个省会城市的水生态文明建设水平进行测度分析。结果显示长沙、杭州、成都和贵阳的城市水生态文明综合得分靠前,上海、南京得分较低,并且与其他城市相比差距较为明显;将长江经济带11个省会城市的水生态文明状况划分为5个等级,以体现不同城市水生态文明的差异性,并按空间格局分析了长江经济带东部、中部和西部三大区域的水生态文明程度。     

Spatial and Seasonal Variations of Disinfection Byproducts (DBPs) in Drinking Water Distribution Systems of Istanbul City,Turkey

This study presents the seasonal and spatial variations of trihalomethanes (THMs) and haloacetic acids (HAAs) in 30 sampling points within three water distribution systems of Istanbul City, Turkey. The effects of surface water quality, seasonal variation, and species differences were examined. The occurrence of chlorinated THMs and HAAs levels was considerably lower in the system in which raw water is subjected to pre-ozonation versus pre-chlorination. Seasonal analysis of the data indicated that the median concentration of four THMs (THM₄) was higher than nine HAAs (HAA₉) concentrations in all three distribution systems sampling points. For all distribution systems monitored, the highest median THM₄ and HAA₉ concentrations were observed in the spring and summer season, while the lowest concentrations of these disinfection byproduct (DBP) compounds were obtained in the fall and winter period. Due to the higher level of bromide in supplying waters of these two systems, moderate levels of brominated DBP species have been observed in the Kagithane and Buyukcekmece distribution systems districts. In fact, Spearman partial correlations (Spearman rank correlation coefficients [rs]) tend to be higher among analogues in terms of number and types of substituent, especially TCAA with TCM (rs 0.91), and DBAA with DBCM (rs 0.90). In contrast, the hydraulic (residence time and flow rate) and chemical mechanisms (hydrolysis, volatilization, and adsorption) affect the fate and transport of DBPs in distribution systems. Seasonal and spatial variations of DBPs presented in this study have important implications on regulatory issues and from an epidemiological point of view.     

西安大气气相中的多环芳烃

利用PUF被动采样器于2008年8月—2009年7月采集了西安大气样品,研究了大气气相中多环芳烃（PAHs）的含量和季节分布特征。结果表明,西安大气气相中16种美国EPA优控的PAHs（Σ16PAHs）质量浓度为10.9-489.6 ng/m3（平均为143.4 ng/m3）,四季具有明显的季节差异,依次为夏季（62.5 ng/m3）〈春季（80.1 ng/m3）〈秋季（175.8 ng/m3）〈冬季（255.2 ng/m3）。气相中PAHs主要以3-4环为主,占总量的86.5%-94.1%。利用主成分分析法判断四季气相中PAHs的污染来源类型,主要为燃煤和机动车尾气及生物质燃烧的复合源。     

Comprehensive quality assessment of municipal organic waste composts produced by different preparation methods

In the first part of this work, the effect of municipal organic waste (MOW) composts on plant growth was evaluated in a greenhouse trial. The treatments included soil amended with 14 different composts (prepared by shredding, adding wood shavings, cocomposting with biosolids or vermicomposting), an inorganically fertilized soil, and a control soil. All of the treatments significantly increased plant growth compared to the control, and yields of three of the amended treatments were as high as that of the inorganic fertilizer treatment. When comparing differently prepared composts to the conventional compost, it was found that cocomposting MOW with biosolids was the method which most positively influenced yields (26-41% yield increases). In the second part of this work, we evaluated the effects of the different preparation methods on compost quality, using a multivariate approach. Three main quality aspects were considered collectively in a principal component analysis: organic matter and nutrient concentrations, degradability and capacity to mineralize these nutrients, and plant growth. The model was restricted to the first and second components (PC1 and PC1) which accounted for 94% of data variance. On the resulting factorial plane, four groups were distinguished. Each of the groups was compared to the reference compost to determine quality increases or decreases. Based on this analysis, it was found that cocomposting MOW with biosolids produced the highest quality products (higher total nutrient and OM concentration, nutrient mineralization potential, and plant growth). Addition of wood shavings increased OM concentration, but reduced quality in terms of the other aspects studied. Shredding was only effective to increase product quality when it was not combined with other methods, whereas vermicomposting only increased quality when MOW was not mixed with biosolids.