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131.
Prior studies have suggested that despite increasing sustainability awareness, many consumers are confused about the impact of green products on their health and the environment. Unlike those studies that privilege professional discourse and adopt unrealistic presumptions of rationality and morality, this article showcases consumers as active co-producers of value and meanings. Using netnography, it analyzes social media conversations around Naked Juice and Innocent smoothies—two products marketed as healthy, all-natural, and environmentally sustainable beverages. The findings reveal a baseline picture of the products' virtues of healthiness feeling (hedonic) and holistic health image (symbolic). The article illustrates how this moral conception was dynamically constructed and transformed in the course of consumers' communicative practices. It proposes three discursive strategies by which consumers negotiate the nature and boundaries of good and bad choices vis-à-vis the products: highlighting (separating virtue from vice), balancing (reconciling virtue and vice), and resisting (reconstructing virtue as vice).  相似文献   
132.
采用活性污泥对经炉渣吸附后的松香废水进行二级生化处理。试验过程中对污泥进行驯化培菌;试验结果表明,经驯化的污泥对松香废水进行二级处理,COD_(Cr)、BOD_5的去除率分别达到65.5%和82.3%,色度由724倍降低到135倍,为开发松香废水治理的实用技术提供了途径。  相似文献   
133.
本文对多拉纳萨依金矿次生晕中金含量空间变化性进行自相关分析,并用对自相关系数进行最小二乘法拟合。通过计算方差与假设样长的关系,考核了一阶马尔科夫模型。利用最佳双边指数滤波器,输入信号(记录)进行滤被面得出各测线上金的信号输出模塑。  相似文献   
134.
Integrating mitigation and adaptation (M&A) is a practical reality for climate change response policy, despite a range of conceptual and methodological challenges. Based on the papers in this special issue, some preliminary findings about appropriate integrated portfolios are offered, along with several implications for climate policy.  相似文献   
135.
城市垃圾焚烧处理中重金属和有机氯化物的二次污染与防治   总被引:17,自引:0,他引:17  
概述城市垃圾焚烧法处理的二次污染问题,着重分析重金属和有机氯化物二次污染物的形成和排放机制,结合我国实际,提出我国垃圾焚烧处理中重金属和有机氯化物二次污染的防治措施。  相似文献   
136.
The biogenic species α-pinene, β-pinene, and d-limonene are among the most abundant monoterpenes emitted globally. They are also important precursors to secondary organic aerosol (SOA) formation in the atmosphere. This study involves the development of proposed oxidation mechanisms for these three species. Semi- and non-volatile oxidation products with the potential to lead to SOA formation are predicted explicitly. Simulation code that describes the gas-phase oxidation mechanisms including reactions that lead to ozone (O3) formation is coupled to an equilibrium absorptive partitioning code. The coupled model is used to simulate both gas-phase chemistry and SOA formation associated with oxidation of these three species in chamber experiments involving single as well as multiple oxidants. For the partitioning model, required molecular properties of the oxidation products are taken from the literature or estimated based on structural characteristics. The predicted O3 and SOA concentrations are typically within ±50% of measured values for most of the experiments except for the experiments with low initial hydrocarbon concentrations and the nitrate radical experiments with α-pinene. The developed model will be used to update a gas-phase chemical mechanism and a SOA formation module used in a three-dimensional air quality model.  相似文献   
137.
Bird song is a typical sexual trait that may have evolved at least partly to reflect health and vigor. However, the role of pathogens in modulating acoustic communication systems in birds is still less than clear as studies testing the relationship between parasites and song have provided inconsistent results both within and among species. It is often neglected that avian song is complex trait consisting of numerous and variable features with potentially different biological backgrounds. By using meta-analytic approaches to the available intraspecific evidence I demonstrate that different roles are applicable to song traits with different signal design, which could explain, to some extent, the inconsistency of results. I found that condition-dependent, performance-related traits are more closely related to immediate health status, whereas condition-independent features are more likely to be associated with intrinsically determined parasite resistance. Hence, parasitism may mediate the evolution of different acoustic features. Considering the signal function of songs, a communication system depends on the reaction of the receivers, but little is known about how mate choice and male–male competition are affected by parasite-mediated song production. This review of the literature thus suggests that receivers of songs may benefit by responding to these acoustic signals of health through the acquisition of resistance genes, paternal care of superior assistance, success in territory disputes, and the avoidance of directly transmitted parasites.  相似文献   
138.
Summary Adult male tree lizards, Urosaurus ornatus, practise alternative (territorial or sneaker/satellite) reproductive strategies that are correlated with differences in throat color and body size. In this study we raised tree lizards from hatching in the laboratory to examine the question of whether the phenotypic expression of secondary sex coloration and body size can be facultatively influenced by social or abiotic environmental factors. We compared males reared in the laboratory under different social and environmental conditions to males in the field and found no effect of different conditions on phenotypic differentiation (Figs. 2–4). Thus, phenotypic differences between morphs probably result largely from nonfacultative expression of different genotypes. This suggests that alternative male morphs practise a mixed evolutionary stable strategy (ESS) rather than one morph making the best of a bad situation. However, in the context of ESS theory it is difficult to explain our further result that the nonterritorial morph in this species grows faster and reaches a larger adult body size than the territorial morph (Fig. 5).  相似文献   
139.
反硝化除磷工艺中二次曝气作用分析   总被引:2,自引:1,他引:1  
王春英 《环境科技》2008,21(4):72-74
反硝化除磷工艺是根据反硝化除磷菌开发的新工艺.结合试验重点探讨了二次曝气在该工艺中的作用:吹脱反硝化产生的附着于活性污泥上的氮气;缺氧段硝酸盐不足时提供O2作为二级电子受体使DPB污泥充分吸磷:p(COD)/p(N),p(COD)/p(P)比值偏高时,再生活性污泥。指出二次曝气在反硝化除磷工艺中具有重要作用。  相似文献   
140.
分析了地震发生后,可能发生的火灾、有毒有害物泄漏、水源污染等多种次生灾害,及目前现有的震后环境监测手段,提出针对可能的污染状况,应采取的环境监测措施及方法。  相似文献   
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