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841.
Abstract

Cooking of foods and the burning of biomass and fossil fuels in stoves are the main sources of cooking fumes, with carbon black and polycyclic aromatic hydrocarbons as main components. The toxicity of carbon black and polycyclic aromatic hydrocarbons has been well studied individually, but the combined toxicity is much less understood. Carbon black can adsorb benzo(a)pyrene to form a complex which displays an altered physical form which in this study has been constructed to simulate particles in the cooking fumes and explore the combined toxic effect on rat alveolar macrophages. The complex-induced cell apoptosis and blocked cell autophagy flux compared with both individually. The mechanism of toxicity may be by intracellular reactive oxygen species generation, impairing the mitochondrial membrane potential and activating apoptosis signaling pathways.  相似文献   
842.
Policy-makers are interested in cost-effective and socially acceptable ways of encouraging the public to adopt more environmentally-friendly lifestyles. One area which UK policy-makers are focussing on is ‘catalyst behaviour’, the notion that taking-up a new behaviour (such as recycling) may cause people to adopt other pro-environmental behaviours. Yet, evidence for such ‘spill-over’ effects is so far limited, and it is unclear when and how cross-situational motivations (e.g., pro-environmental identity) may predict behaviour and when contextual factors are more important. We report on a postal survey (N = 551) of pro-environmental behaviours amongst the UK public. We assess the influence of pro-environmental self-identify on consistency across a range of behaviours. Pro-environmental values, perceived behavioural control, subjective norm, attitudes, and demographic factors were also measured. Findings show self-identity to be a significant behavioural determinant over and above theory of planned behaviour variables for carbon offsetting behaviour. However, pro-environmental self-identity was only a significant predictor for certain other pro-environmental behaviours; background variables were also important predictors. Limitations of the study, and implications for theory and policy, are discussed.  相似文献   
843.
Canopies of adult European beech (Fagus sylvatica) and Norway spruce (Picea abies) were labeled with CO2 depleted in 13C to evaluate carbon allocation belowground. One-half the trees were exposed to elevated O3 for 6 yrs prior to and during the experiment. Soil-gas sampling wells were placed at 8 and 15 cm and soil CO2 was sampled during labeling in mid-late August, 2006. In beech, δ13CO2 at both depths decreased approximately 50 h after labeling, reflecting rapid translocation of fixed C to roots and release through respiration. In spruce, label was detected in fine-root tissue, but there was no evidence of label in δ13CO2. The results show that C fixed in the canopy rapidly reaches respiratory pools in beech roots, and suggest that spruce may allocate very little of recently-fixed carbon into root respiration during late summer. A change in carbon allocation belowground due to long-term O3 exposure was not observed.  相似文献   
844.
Nearly three-quarters of global natural rubber production is used to produce tyres, supporting mobility around the globe. The projected increase in mobility could contribute to further expansion of rubber plantations and impact tropical ecosystems. We quantified the use of natural rubber in tyres in the European Union (EU), the corresponding land footprint, and explored drivers of tyre use using country-specific transport statistics and trade registers of rubber goods. Five percent of the world’s natural rubber is consumed in tyres used in the EU, using up to a quarter of the area under rubber plantations in some producing countries. Car use is responsible for 58% of this consumption, due to car-dependent lifestyles that are associated with economic prosperity and spatial planning paradigms. While the EU’s transport policy focuses on reducing dependence on fossil-fuels, cross-cutting policies are needed to address car-dependency and reduce the EU’s land footprint in tropical landscapes without compromising progress towards decarbonisation.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01579-x.  相似文献   
845.
新型水处理活性炭选型技术   总被引:8,自引:5,他引:3  
活性炭依其原料不同、生产工艺不同,而有不同的吸附性能.使用简易的活性炭选型方法,可以减少应用测试时的备选炭型,从而大大降低活性炭水处理技术的运行成本.以碘值、甲基蓝值、苯酚值和丹宁酸值4种吸附容量性能指标为依据的活性炭选型技术,可以有效地预测活性炭对于水中各种大小不同污染物的去除能力.BET测试结果证明了这4项指标数据对于活性炭孔径分布预测的准确性.2,4-二氯苯酚和腐殖酸等目标化合物的吸附容量实验结果也都验证了这4项指标的预测功用,说明这种简便的活性炭选型技术有着广泛的应用价值.  相似文献   
846.
以Na2CO3和NaHCO3的混合液作为用碱液吸收CO2气体的模拟液,用两室单阴膜电渗析装置对其在小于5V的低电压下进行脱碳处理,并且得出电渗析的方法可以增加回收液中Na2CO3和NaHCO3的浓度比,减少碳的总浓度,起到了对CO2的碱吸收液再生利用的作用。  相似文献   
847.
超临界二氧化碳中的化学反应   总被引:2,自引:0,他引:2  
介绍了超临界二氧化碳的性质,总结了超临界二氧化碳中的加氢反应、氢甲酰化反应和氧化反应,并找出存在的问题,提出解决的建议。  相似文献   
848.
采用顶空气相色谱(GLC-HS)分析技术测定了代森锰锌、ND-901中代森锰锌在大棚黄瓜上的残留动态。喷施70%代森锰锌可湿性粉剂的500倍、250倍药液,测出黄瓜上原始沉积量分别为0.88~2.70mg/kg、1.11~3.79mg/kg;半衰期为1.6~9.5天、2.3~10.9天。黄瓜叶片上原始沉积量分别为148.01~164.08mg/kg、246.26~254.51mg/k;半衰期为15.8~16.2、18.4天。ND-901中代森锰锌的残留量均低于单剂。另外,自来水去污处理可有效地减少瓜上代森锰锌的残留量,平均去污率87%。  相似文献   
849.
The concentrations of EC, BC and dust aerosols were determined for atmospheric samples collected from an observation station in Xi'an, China. The results show that the averaged correlation coefficient between EC and BC was founded to be 0.72 with 0.81 (n = 49) in autumn, 0.70 (n = 112) in winter and 0.69 (n = 57) in spring, respectively. Absorption coefficients of dust aerosol were estimated to be 2.7 m2 g−1 in autumn and 4.4 m2 g−1 in winter. The comparison of absorption coefficients of dust aerosol with those of BC implies that BC is the principal light-absorbing aerosol over Xi'an atmosphere. By combining thermal analysis of elemental carbon and dust contents in the aerosol samples, however, the fraction of dust absorption to total light absorption is estimated to be 19% in autumn and 31% in winter, respectively.  相似文献   
850.
Arctic warming is causing ancient perennially frozen ground (permafrost) to thaw, resulting in ground collapse, and reshaping of landscapes. This threatens Arctic peoples'' infrastructure, cultural sites, and land-based natural resources. Terrestrial permafrost thaw and ongoing intensification of hydrological cycles also enhance the amount and alter the type of organic carbon (OC) delivered from land to Arctic nearshore environments. These changes may affect coastal processes, food web dynamics and marine resources on which many traditional ways of life rely. Here, we examine how future projected increases in runoff and permafrost thaw from two permafrost-dominated Siberian watersheds—the Kolyma and Lena, may alter carbon turnover rates and OC distributions through river networks. We demonstrate that the unique composition of terrestrial permafrost-derived OC can cause significant increases to aquatic carbon degradation rates (20 to 60% faster rates with 1% permafrost OC). We compile results on aquatic OC degradation and examine how strengthening Arctic hydrological cycles may increase the connectivity between terrestrial landscapes and receiving nearshore ecosystems, with potential ramifications for coastal carbon budgets and ecosystem structure. To address the future challenges Arctic coastal communities will face, we argue that it will become essential to consider how nearshore ecosystems will respond to changing coastal inputs and identify how these may affect the resiliency and availability of essential food resources.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01666-z.  相似文献   
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