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61.
Biogenic volatile organic compounds (BVOCs) in the atmosphere play important roles in the formation of ground-level ozone and secondary organic aerosol (SOA) in global scale and also in regional scale under some condition due to their large amount and relatively higher reactivity. In places with high plant cover in the tropics and in China where air pollution is serious, the effect of BVOCs on ozone and secondary organic aerosols is strong. The present research aims to provide a comprehensive review about the emission rate, emission inventory, research methods, the influencing factors of BVOCs emissions, as well as their impacts on atmospheric environment quality and human health in recent years in Asia based on the summary and analysis of literatures. It is suggested to use field direct measurement method to obtain the emission rate and model method to calculate the emission amount. Several recommendations are given for future investigation and policy development on BVOCs emission.  相似文献   
62.
真菌修复砷污染土壤是一种能够有效吸附固化环境中砷的重要措施.生物炭作为目前修复重金属的热点,其多空疏松的结构、较高的离子交换量、丰富的有机碳含量等都说明了其在土壤修复中的地位.为了探究生物炭与青霉菌在修复砷污染土壤的同时对土壤中微生物活性及其多样性的影响,在室内孵育条件下,运用Biolog法研究了3×3随机区组试验(3个生物炭梯度分别为0%、2%、4%,3个青霉菌梯度分别为0%、10%、20%)下土壤微生物对不同类型碳源的利用能力以及多种功能性指数的影响.结果表明:①添加青霉菌与生物炭后,土壤中有效砷含量较对照组显著下降,从而影响其微生物群落功能多样性.②砷污染土壤中微生物群落功能多样性、碳源利用丰富度随生物炭浓度梯度的升高呈先升后降的趋势.③高接菌量(20%)与低接菌量(10%)对砷污染土壤中微生物群落功能多样性的影响没有显著性差异.④2%生物炭与10%青霉菌处理土壤中微生物群落功能多样性、碳源利用丰度最高.⑤青霉菌对胺类及少部分酸类碳源的利用能力较弱(AWCD < 0.5,AWCD为Biolog微平板孔中溶液吸光值平均颜色变化率),对氨基酸类中大部分碳源以及脂类碳源的代谢能力较强(AWCD>1.0),对糖类、酚酸类的代谢能力稍弱(AWCD为0.3~1.0),青霉菌对D-半乳糖醛酸、L-天冬酰胺酸、L-丝氨酸、L-精氨酸、r-羟基丁酸这5种碳源的利用率最高(AWCD>1.2).研究显示,低浓度生物炭可增加砷污染土壤中微生物群落多样性,生物炭含量的继续增加会对微生物产生抑制作用;青霉菌添加到砷污染土壤后,会显著提升砷污染土壤中微生物的群落功能多样性,改善砷污染土壤中微生的物群落结构;青霉菌的优势碳源大多为植物根系分泌物,可为后续青霉菌与超积累植物复合修复砷污染土壤提供参考.   相似文献   
63.
为揭示升流式厌氧污泥床(UASB)反应器启动运行效能与互营丙酸降解菌群数量之间的关系,以稀释的玉米淀粉生产废水为底物,考察了UASB启动期的运行特征,并采用实时荧光定量PCR技术(qPCR)分析了互营丙酸降解菌群(丙酸氧化菌和产甲烷菌)的演替规律.结果表明,在进水COD 2000mg/L和水力停留时间(HRT)24h条件下,经过38d的连续运行,COD去除率达到了91.9%.当HRT分阶段缩短至8h时,比产甲烷速率达到了315LCH4/(kg COD·d),且形成了沉降性能良好的颗粒污泥.qPCR检测结果表明,至少有5种已鉴定的丙酸氧化菌存在于UASB反应器中.Pelotomaculum propionicum为接种污泥中的主要丙酸氧化菌,约占检测到丙酸氧化菌总数的45.7%.它的数量随着HRT缩短不断减少.而Syntrophobacter sulfatireducens和S.wolinii的数量随着HRT缩短不断增加,并在启动完成时达到最大值,分别为1.3×103,5.5×103个16S rRNA基因拷贝数/ng DNA,演替成为成熟颗粒污泥中的优势丙酸氧化菌群.Methanobacterium和Methanosarcina为接种污泥中的主要氢营养型产甲烷菌和乙酸营养型产甲烷菌,其数量随着HRT的缩短而逐渐减少,而Methanospirillum和Methanosaeta的数量随HRT的缩短逐渐增加,成为成熟颗粒污泥中的优势产甲烷菌群.  相似文献   
64.
Mitigation and Adaptation Strategies for Global Change - Low-carbon pilot (LCP) policy aims to not only achieve economic development but also address climate change problems in China. With a...  相似文献   
65.

This study explored the national hydrogen refueling infrastructure requirement along major United States (US) interstate highway corridors to support the deployment of fuel cell electric trucks (FCETs) for the national long-haul trucking fleet. Given the long-haul trucking shipment demand in 2025 projected by the Freight Analysis Framework, locations and capacities of hydrogen stations were identified for inter-zone freight flows, and the total daily refueling demand was estimated for intra-zone flows for each FAF zone. Based on the infrastructure deployment results, we conducted an economic feasibility analysis of FCETs by evaluating the total ownership cost. We found that when the FCET penetration is relatively high (e.g., 10% penetration), FCETs become more competitive in terms of fuel cost and idling cost and could be economic viable if the incremental vehicle cost is reduced to meet the near-term FCET technology cost targets and the liquefaction cost is reduced to an optimal case. We also observed that the station cost depends on regional factors, particularly regional demand, which is used to determine station capacity. Thus, one possible strategy for station roll-out is to have early investment in target regions where station costs are expected to be relatively low such as the Pacific and West South Central regions.

  相似文献   
66.
TiO_2 nanoparticles(NPs) could adversely impact aquatic ecosystems. However, the aggregation of these NPs could attenuate this effect. In this work, the biological effects of TiO_2 NPs on a marine microalgae Isochrysis galbana were investigated. The aggregation kinetics of TiO_2 NPs under different conditions was also investigated to determine and understand these effects. Results showed that, though TiO_2 NPs had no obvious impact on the size and reproducibility of algal cells under testing conditions, they caused a negative effect on algal chlorophyll, which led to a reduction in photosynthesis. Furthermore, fast aggregation of TiO_2 NPs occurred under all conditions, especially at the pH close to the p Hzpc. Increasing ionic strength and NP concentration also enhanced the aggregation rate.The aggregation and the following sedimentation of TiO_2 NPs reduced their adverse effects on I. galbana.  相似文献   
67.
Sewage sludge (SS) and deinking sludge (DS) were used to comparatively study the hydrothermal dewatering of sludge with different components. For a better overview, an insight into the relationship between physicochemical properties and dewaterability of hydrothermal sludge was provided. Results found that not all kinds of sludge were suitably conditioned by hydrothermal treatment (HT) in term of the elevation of dewaterability. Higher hydrothermal temperature tended to enhance the dewaterability of SS rather than DS, which was supported by the variation of their physicochemical properties (including water distribution, bonding energy, extracellular polymeric substance (EPS), particles size, acid functional groups and zeta potential in this study). In addition, the changes in surface morphology suggested that the reverse effect of HT on sludge dewaterability was mainly due to their dewatering behavior. For SS, the destruction of EPS structure leaded to the release of bound water, thereby strengthening sludge dewatering. Conversely, “Bridging effect” generated by lignocellulose in DS was beneficial for sludge dewatering; however, the increasing hydrothermal temperature degraded part of lignocellulose and weakened “bridging effect”, finally resulting in worse dewaterability of DS.  相似文献   
68.
生活垃圾焚烧设施的建立是解决城市生活垃圾逐年增多的有效方式之一,但其所引发的环境与健康问题成为公众关注的热点。基于广东省对生活垃圾焚烧设施的研究,以环境管理为目标,结合国内外在该领域的研究现状,提出广东省生活垃圾焚烧设施环境与健康风险评估构架。通过该构架的多年实践,总结了广东省生活垃圾焚烧设施环境与健康风险评估研究所取得的成效,有望将该成果推而广之,从而使该行业实现绿色生态的蓬勃发展。  相似文献   
69.
为了解重庆市九龙坡区城区和城郊大气污染物浓度特征,分析了城区和城郊国控空气站点2014年3月~2015年2月典型污染物的浓度变化。结果表明,除O_3表现出夏高冬低的季节变化趋势外,其它污染物均表现出冬高夏低的季节变化趋势。PM_(2.5)污染最严重,城区和郊区日均值超标率分别为31.4%和33.4%。城区和城郊的PM_(2.5)浓度之间没有显著性差异(p0.05),城郊O_3浓度显著高于城区(p0.01),NO_2、SO_2、CO和PM_(10)则是城区显著高于城郊(p0.01)。  相似文献   
70.
构建雾霾环境天气下户外体育运动生理健康指标参数,以最大摄氧量(VO2)、最大通气量(VEmax)、氧脉搏O2P、心率(HR)等参量为约束指标,构建户外体育运动人群身体健康指标的约束体系,采用心电图的负荷试验和代谢分析实验方法测试雾霾环境天气下对户外体育运动人群健康影响,根据受测运动员的气体代谢和心肺功能指标进行雾霾环境天气下运动人群的心肺机能特征分析。雾霾环境天气下,应当减少户外运动,在空气质量好的环境下进行一定的有氧运动,避免吸入污染空气,导致肺部疾病。  相似文献   
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