东莞工业集中区夏季臭氧污染与非污染期间VOCs组分特征及其来源

为探讨东莞典型工业区夏季大气挥发性有机物（VOCs）污染特征及来源,于2020年夏季在厚街镇对大气环境中56种VOCs开展了在线观测,并同步收集了臭氧（O₃）、氮氧化物（NO_x）和一氧化碳（CO）等气体污染物浓度和气象因子等资料,在此基础上分析了VOCs总体积分数和主要物种体积分数特征,进一步估算了主要VOCs物种对臭氧生成潜势的贡献和不同臭氧浓度下VOCs的主要污染源贡献率.结果表明,观测期间56种VOCs的体积分数平均值为53.1×10^-9,其中φ（芳香烃）、φ（烷烃）、φ（烯烃）和φ（炔烃）分别为24.7×10^-9、23.7×10^-9、3.9×10^-9和0.7×10^-9.与非臭氧污染期间相比,臭氧污染期间φ（芳香烃）、φ（烷烃）、φ（烯烃）和φ（炔烃）分别上升约10%、43%、38%和98%.无论是臭氧污染还是非臭氧污染期间,芳香烃对臭氧生成潜势的贡献率均最大,其次为烷烃、烯烃和炔烃.整个夏季观测期间,溶剂源、液化石油气泄漏、化石燃料燃烧源和油气挥发源对VOCs的贡献率分别为60%±20%、16%±11%、15%±11%和9%±6%;臭氧污染期间,溶剂源的贡献率下降到44%,而液化石油气泄漏和油气挥发源的贡献率分别上升到21%和16%.     

在线柱浓缩-液相色谱法测定水体中痕量敌草快和百草枯

采用在线柱浓缩-超快速液相色谱联用技术测定水体中痕量百草枯和敌草快.水样无需样品前处理,过滤后即可进样.采用固相萃取小柱富集待测物,以色谱梯度泵完成样品的净化后,利用阀切换技术将待测物反冲至分析柱进行分离,以二极管阵列检测器定量.方法在1.0—20.0μg.L-1范围内线性良好,百草枯和敌草快的线性相关系数分别为0.9997和0.9989.百草枯和敌草快的检出限(S/N=3)分别为0.10、0.12μg.L-1,加标回收率在96.0%—98.0%之间.用所建立的方法测定了水中痕量的百草枯与敌草快的含量,结果令人满意.     

Take Action Now: Motivational Framing and Action Requests in Climate Advocacy

This article explores similarities and differences between Internet-mediated climate change advocacy organizations and their legacy counterparts. It relies on a content analysis of advocacy emails produced by Environmental Defense Fund, Natural Resources Defense Council, Sierra Club, Greenpeace USA, League of Conservation Voters, Climate Reality Project, 1Sky, and 350.org. The study finds differences and similarities in strategic Internet use, including greater emphasis by climate groups on high threshold, offline actions; greater emphasis by legacy groups on low threshold, online actions; and high reliance by both framings that demand accountability from political elites. Implications for Internet-mediated and climate advocacy are discussed.     

Quantifying the role of online news in linking conservation research to Facebook and Twitter

Conservation science needs to engage the general public to ensure successful conservation interventions. Although online technologies such as Twitter and Facebook offer new opportunities to accelerate communication between conservation scientists and the online public, factors influencing the spread of conservation news in online media are not well understood. We explored transmission of conservation research through online news articles with generalized linear mixed‐effects models and an information theoretic approach. In particular, we assessed differences in the frequency conservation research is featured on online news sites and the impact of online conservation news content and delivery on Facebook likes and shares and Twitter tweets. Five percent of articles in conservation journals are reported in online news, and the probability of reporting depended on the journal. There was weak evidence that articles on climate change and mammals were more likely to be featured. Online news articles about charismatic mammals with illustrations were more likely to be shared or liked on Facebook and Twitter, but the effect of news sites was much larger. These results suggest journals have the greatest impact on which conservation research is featured and that news site has the greatest impact on how popular an online article will be on Facebook and Twitter. Cuantificación del Papel de las Noticias En Línea en el Enlazamiento de la Investigación para la Conservación con Facebook y Twitter     

在线实时监测微气泡尺寸系统的构建及效果分析

为在线监测污水处理、水体增氧和气液相化学反应过程中的气泡粒径的实时变化情况,构建了一种在线测试微气泡群的测试系统,并进行气泡粒径的实时监测;将微细气泡发生装置产生的气泡水引入到粒度分析仪的测试区样品池,形成一个稳定的动态循环流动的系统;通过调节分流阀和分散剂阀同时实现样品的均匀混合和在线取样,再将样品输送至样品池进行快速检测,实现气泡尺寸的在线实时监测。结果表明：当遮光率为10%,从样品槽混合好的样品到样品池的距离为6 cm,测试时间为10 s时,可获得测试微细气泡粒径的最佳条件,精度为±6%;溶气-释气法产生的微细气泡粒径为10~150 μm;随着进气量的增加,气泡的尺寸逐渐增加,其对应的体积比逐渐较小;气泡的粒径还会受到液相水样的影响,当液相为循环水时,气泡粒径呈双峰分布;当液相为新鲜自来水时,气泡粒径呈单峰分布。微气泡尺寸在线测试平台具有具有重复性好、精度高、可控性强、操作简单等特点。本研究结果可为微气泡在污水处理、水体增氧和气液相反应等场合的应用提供参考。     

在线液液萃取-气相色谱-质谱法测定生活饮用水中卤代乙腈

优化建立了在线液液萃取-气相色谱-质谱法测定饮用水中7种卤代乙腈的方法。通过多功能在线进样装置,研究设计了在线液液萃取的技术流程,优化了液液萃取关键参数,并建立了气相色谱-质谱检测方法。该方法对氯乙腈、二氯乙腈、三氯乙腈、溴乙腈、二溴乙腈、溴氯乙腈和碘乙腈等7种卤代乙腈都有较好的检测灵敏度,方法检测限为0.1~0.8 μg/L,纯水中高浓度加标回收率为72.0%~91.4%,精密度为1.8%~3.9%。经技术对比和应用验证,该方法具有高效灵敏、简便快速等特点,样品检测无干扰,自动化程度高,适用于饮用水中卤代乙腈类消毒副产物的检测。     

Focus and social contagion of environmental organization advocacy on Twitter

Agriculture, overexploitation, and urbanization remain the major threats to biodiversity in the Anthropocene. The attention these threats garner among leading environmental nongovernmental organizations (eNGOs) and the wider public is critical in fostering the political will necessary to reverse biodiversity declines worldwide. I analyzed the advocacy of leading eNGOs on Twitter by scraping account timelines, screening content for advocacy relating to biodiversity threats and, for prevalent threats, further screening content for positive and negative emotional language with a sentiment lexicon. Twitter advocacy was dominated by the major threats of climate change and overexploitation and the minor threat of plastic pollution. The major threats of agriculture, urbanization, invasions, and pollution were rarely addressed. Content relating to overexploitation and plastic pollution was more socially contagious than other content. Increasing emotional negativity further increased social contagion, whereas increasing emotional positivity did not. Scientists, policy makers, and eNGOs should consider how narrowly focused advocacy on platforms like Twitter will contribute to effective global biodiversity conservation.     

丙烯槽车特大泄漏事故的应急处置方法

如何快速有效地处置危险化学品槽车突发泄漏事故，目前还是一个世界性的难题。本文介绍了吉林市6．26丙烯槽车特大泄漏事故发生后的报警、接警、启动应急预案、现场侦察、现场警戒、禁绝火源、交通管制、紧急疏散、喷雾稀释、着装防护、丙烯的特性、健康危害、急救措施等。阐述了夹具捆绑法带压堵漏的机理，提供了丙烯泄漏槽车的勘测数据、夹具设计思路、夹具制造图纸、现场应急处置方法及现场照片。本案例表明，只要有可靠的安全措施及特殊的技术手段，危险化学品槽车泄漏事故是可以进行应急处置的，实现控制、降低、消除泄漏，避免灾害性事故的发生。文中方法同样适用于铁路槽车泄漏事故的应急处置。     

准组织化:“互联网+线上应急救援”的实践路径和现实困境*—以河南郑州“7·20”特大暴雨灾害事件为例

为响应我国应急管理现代化和信息化建设需要,采用参与式观察、网络民族志和深度访谈方法,从准组织化集体行动视角切入,对河南郑州“7·20”特大暴雨灾害事件中救援模式相对成熟的“互联网+线上应急救援”实践路径和现实困境进行探讨。研究结果表明:线上应急救援实践路径涵盖聚合、运转、高效、离散4个阶段,且以持续不断的行动流呈现,具有准组织化集体行动特征;同时,线上救援形式面临“合法性”不确定、救援质量不稳定、风险评估主观性和政府正式沟通渠道有限性等现实困境,研究结果可为我国应急管理信息化建设提供参考。     

Characterising the performance of a tapered scrubber for controlling particulate emission

The performance of a modified tapered scrubber using water is presented in this article. The column is fabricated with internals so as to improve the performance of a simple tapered bubble scrubber. Experimentation indicates that the system developed can obtain almost 100% particulate (fly ash) removal efficiency under certain hydrodynamical conditions and the removal efficiency has been found to be higher than the existing similar systems. An empirical correlation is put forward for the prediction of removal efficiency as a function of relevant variables of the system. Experimental results agree very well with the correlation.