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1.
Haoran Feng Min Liu Wei Zeng Ying Chen 《Frontiers of Environmental Science & Engineering》2021,15(4):78
2.
Boyi Cheng Yi Wang Yumei Hua Kate V. Heal 《Frontiers of Environmental Science & Engineering》2021,15(4):73
3.
采用A/O-电催化氧化法处理村镇垃圾中转站渗滤液,并针对工艺核心电催化氧化单元的相关运行参数进行探究。结果表明:使用椰壳活性炭作为粒子电极基体材料,以Sn-Sb作为活性催化剂,在初始pH值<7、外加电压15 V条件下,电解中转站垃圾渗滤液效果较好;联合工艺连续运行阶段,当水力停留时间达到11 d时,原水COD从(31 098±1 270)mg/L下降到(391±44)mg/L,渗滤液可生化性(B/C)从0.336±0.020提升到0.719±0.024,可生化性显著增强。 相似文献
4.
对2020年4月—2021年3月北京市建成区挥发性有机物(VOCs)的化学特征、污染来源及其对臭氧(O3)污染的影响进行了研究。结果显示:O3日最大8 h滑动平均值在臭氧季(4—9月)均值为134 μg/m3,是非臭氧季(10月至次年3月)均值(59.6 μg/m3)的2.2倍。臭氧季VOCs体积浓度均值为14.3×10-9,明显低于非臭氧季(21.1×10-9),可能与光化学反应速率和VOCs来源的季节性差异有关。臭氧生成潜势(OFP)贡献率排名前10位的物种在臭氧季和非臭氧季相似,均包括间/对-二甲苯、甲苯、乙烯、邻二甲苯、异戊烷、正丁烷、丙烯、反式-2-丁烯和1,2,4-三甲基苯,但排名有所差异,燃煤源特征明显的乙烯等物种在非臭氧季上升明显,与溶剂使用、油气挥发相关的间/对二甲苯、甲苯、异戊烷和正丁烷等物种在臭氧季上升明显。甲苯/苯的值和异戊烷/正戊烷的值在臭氧季明显高于非臭氧季,反映出机动车排放和油气挥发等在臭氧季影响突出,非臭氧季是燃煤影响显著。基于正交矩阵因子分解模型(PMF),臭氧季解析出机动车尾气排放(40.9%)、溶剂使用(20%)、油气挥发(16.4%)、工业排放(17.6%)和植物排放(5.1%)等5种污染源;非臭氧季解析出机动车尾气(38.9%)、燃烧源(26.3%)、工业排放(17.8%)和溶剂使用(17%)等4种污染源。 相似文献
5.
以天然高分子化合物海藻酸钠(sodium alginate,SA)为骨架,结合磁性Fe3O4和稀土铈离子Ce(Ⅲ)通过溶液反应制备出一种新型的磁性海藻酸铈复合微球(Fe3O4@SA;Ce).采用X射线衍射(XRD)、孔结构比表面积分析(BET)、扫描电子显微镜(SEM)、红外光谱(FT-IR)及振动样品强磁计(VSM)对Fe3O4@SA;Ce的结构进行了表征,并以直接桃红12B(direct red 12B,DR 12B)和直接橙S(direct orange S,DO S)两种染料为吸附对象,探讨了Fe3O4@SA;Ce的吸附剂性能、吸附动力学和热力学.结果表明,Fe3O4@SA;Ce对室温下自然pH染料溶液中DR 12B和DO S均表现出良好的吸附效果,吸附量分别可达464 mg·g-1和730 mg·g-1.在不同温度下(298、313、328 K),Fe3O4@SA;Ce对DR 12B和DO S的吸附过程均可用拟二级吸附动力学方程准确描述.通过等温吸附研究,发现Fe3O4@SA;Ce对两种染料的等温吸附较好地符合Freundlich模型.各种表征结果表明,SA与Ce(Ⅲ)和Fe3O4交联反应后生成的Fe3O4@SA;Ce凝胶球表面有大量深浅不一的褶皱沟纹,形貌发生了显著变化.作为一种绿色环保、制备方法简单、可高效吸附的磁性高分子复合吸附剂,Fe3O4@SA;Ce对高浓度染料具有很好的吸附效果,期望能够在染料废水处理中得到广泛应用. 相似文献
6.
This paper documents the effect of primary forest cover loss on increased incidence of malaria. The evidence is consistent with an ecological response. I show that land use change, anti-malarial programs or migration cannot explain the effect of primary forest cover loss on increased malarial incidence. Falsification tests reveal that the effect is specific to malaria, with forest cover having no discernible effect on other diseases with a disease ecology different from that of malaria. Back-of-the-envelope calculations indicate that the morbidity-related malaria-reducing local benefits of primary forests are at least $1-$2 per hectare. 相似文献
7.
To overcome adoption barriers and promote battery electric vehicles (BEVs) as an energy efficient consumer transportation option, a number of states offer subsidies to consumers for BEVs. We use a national data set of vehicle registrations and state-level financial incentives to assess the impact of vehicle purchase subsidies on adoption using both difference-in-differences and synthetic controls methods. We find that incentives offered as direct purchase rebates generate increased levels of new BEV registrations at a rate of approximately 8 percent per thousand dollars of incentive offered. Between 2011 and 2015, vehicle rebate incentives are associated with an increase in overall BEV registrations of approximately 11 percent. Our findings indicate incentives offered as state income tax credits do not have a statistically significant effect on BEV adoptions, though we caution this may be a result of limited temporal variation in BEV incentives across our sample. Responses to rebate incentives do not differ significantly by the make of the vehicle purchased (i.e., Tesla and non-Tesla vehicles). We combine our results with recent assessments of marginal environmental costs of electric vehicle charging and measure net welfare effects of BEV subsidy programs. Our analysis indicates these programs are not welfare-improving if only considering benefits associated with avoided emissions. Additional benefits associated with long-term market growth, production cost savings, network externalities, or accelerated innovation could substantially impact the net welfare outcomes. 相似文献
8.
Fishing‐gear restrictions and biomass gains for coral reef fishes in marine protected areas 下载免费PDF全文
Stuart J. Campbell Graham J. Edgar Rick D. Stuart‐Smith German Soler Amanda E. Bates 《Conservation biology》2018,32(2):401-410
Considerable empirical evidence supports recovery of reef fish populations with fishery closures. In countries where full exclusion of people from fishing may be perceived as inequitable, fishing‐gear restrictions on nonselective and destructive gears may offer socially relevant management alternatives to build recovery of fish biomass. Even so, few researchers have statistically compared the responses of tropical reef fisheries to alternative management strategies. We tested for the effects of fishery closures and fishing gear restrictions on tropical reef fish biomass at the community and family level. We conducted 1,396 underwater surveys at 617 unique sites across a spatial hierarchy within 22 global marine ecoregions that represented 5 realms. We compared total biomass across local fish assemblages and among 20 families of reef fishes inside marine protected areas (MPAs) with different fishing restrictions: no‐take, hook‐and‐line fishing only, several fishing gears allowed, and sites open to all fishing gears. We included a further category representing remote sites, where fishing pressure is low. As expected, full fishery closures, (i.e., no‐take zones) most benefited community‐ and family‐level fish biomass in comparison with restrictions on fishing gears and openly fished sites. Although biomass responses to fishery closures were highly variable across families, some fishery targets (e.g., Carcharhinidae and Lutjanidae) responded positively to multiple restrictions on fishing gears (i.e., where gears other than hook and line were not permitted). Remoteness also positively affected the response of community‐level fish biomass and many fish families. Our findings provide strong support for the role of fishing restrictions in building recovery of fish biomass and indicate important interactions among fishing‐gear types that affect biomass of a diverse set of reef fish families. 相似文献
9.
Understanding implications of consumer behavior for wildlife farming and sustainable wildlife trade 下载免费PDF全文
A. Nuno J. M. Blumenthal T. J. Austin J. Bothwell G. Ebanks‐Petrie B. J. Godley A. C. Broderick 《Conservation biology》2018,32(2):390-400
Unsustainable wildlife trade affects biodiversity and the livelihoods of communities dependent upon those resources. Wildlife farming has been proposed to promote sustainable trade, but characterizing markets and understanding consumer behavior remain neglected but essential steps in the design and evaluation of such operations. We used sea turtle trade in the Cayman Islands, where turtles have been farm raised for human consumption for almost 50 years, as a case study to explore consumer preferences toward wild‐sourced (illegal) and farmed (legal) products and potential conservation implications. Combining methods innovatively (including indirect questioning and choice experiments), we conducted a nationwide trade assessment through in‐person interviews from September to December 2014. Households were randomly selected using disproportionate stratified sampling, and responses were weighted based on district population size. We approached 597 individuals, of which 37 (6.2%) refused to participate. Although 30% of households had consumed turtle in the previous 12 months, the purchase and consumption of wild products was rare (e.g., 64–742 resident households consumed wild turtle meat [i.e., 0.3–3.5% of households] but represented a large threat to wild turtles in the area due to their reduced populations). Differences among groups of consumers were marked, as identified through choice experiments, and price and source of product played important roles in their decisions. Despite the long‐term practice of farming turtles, 13.5% of consumers showed a strong preference for wild products, which demonstrates the limitations of wildlife farming as a single tool for sustainable wildlife trade. By using a combination of indirect questioning, choice experiments, and sales data to investigate demand for wildlife products, we obtained insights about consumer behavior that can be used to develop conservation‐demand‐focused initiatives. Lack of data from long‐term social–ecological assessments hinders the evaluation of and learning from wildlife farming. This information is key to understanding under which conditions different interventions (e.g., bans, wildlife farming, social marketing) are likely to succeed. 相似文献
10.
利用化学沉淀法制备磁性四氧化三铁/石墨烯(Fe3O4/GE)纳米复合材料,并将其与H2O2构成非均相Fenton体系用于催化降解水中微量的17β-雌二醇(E2),研究了初始p H值,初始H2O2浓度,催化剂用量对E2降解的影响。结果表明,Fe3O4/GE纳米复合材料在无需外加光源的条件下能够有效催化降解E2。在p H 7.0,E2初始浓度为1 mg/L,初始H2O2浓度为15 mmol/L,Fe3O4/GE投加量为15 mg/L的条件下,反应8 h后可去除92.9%的E2。Fe3O4/GE具有便捷的磁分离特性和稳定的催化活性,经过7次循环使用后对E2的降解效率仍保持在91.5%左右。 相似文献