突发事件机理体系与现代应急管理体制设计

本文为了增加对突发事件的科学认识,提升应急管理的能力水平,首先对突发事件和应急管理的内在机理进行剖析。通过分阶段、划层次地构建"4L-5S"机理分析模型,将二者划归为统一体系,以理清其逻辑内涵;然后,为顺应时代发展特征,满足应急管理的更高要求,实现应急管理工作从非常态协同应对转为常态化职能管理,对现代应急管理体制加以总体设计。从而,突发事件机理体系设计使得我国的突发事件机理研究逐渐过渡至具有阶段性和层次性,现代应急管理体制设计使得我国应急管理整合出具备现代思维理念的逻辑框架。     

A study on oxidative degradation of polyacrylamide in wastewater with UV/FENTON/C4H4O62−

The degradation of polyacrylamide (PAM) in simulate wastewater was studied in UV/Fenton/C₄H₄O₆^2? system. The factors such as molecular ratio of H₂O₂/Fe²⁺/C₄H₄O₆^2?, pH, and the dosage of Fenton reagent that could affect the PAM degradation in the UV/Fenton/C₄H₄O₆^2? system were investigated. The experimental results showed that adding C₄H₄O₆^2? to UV/Fenton system could form photosensitive ferrous complexes, which led to higher degradation efficiency of PAM. The degradation rate of PAM could be up to 95.2% under the following conditions: the concentration of H₂O₂, Fe²⁺, and C₄H₄O₆^2? were 22.5, 2.25, and 2.25 mmol/L, respectively (i.e., molecular ratio of H₂O₂/Fe²⁺/C₄H₄O₆^2? was 10:1:1), the pH value was 3.0.     

磷酸微波活化多孔生物质炭对亚甲基蓝的吸附特性

以甘蔗渣为原料，采用微波辅助H3PO4活化法制备富含含氧酸官能团的中孔生物质炭。通过扫描电子显微镜SEM、傅立叶变换红外光谱FT-IR等技术对生物质炭物理化学性质进行表征，并通过静态实验法，探讨炭样对亚甲基蓝的吸附行为及热力学性质。结果表明，H3PO4活化制备蔗渣生物质炭的适宜条件为浸渍比1：1，烘干时间10h，活化功率900W，活化时间22min，在此条件下制得的生物质炭得率为39．2％，碘值为817mg／g，亚甲基蓝值为229mg／g，为国家一级品标准的1．7倍。红外光谱分析表明，炭样表面以羟基、羰基、羧基等酸性官能团为主。静态吸附实验表明，Freundlich方程与Redlich—Peterson方程能较好地描述等温吸附行为，表现为优惠吸附。热力学研究表明，吸附吉布斯自由能（△G0）〈0，说明吸附反应是自发过程，而吸附标准焓变（△H0）〉70KJ／mol，表明亚甲基蓝在制备炭样上的吸附是吸热反应，升温有利于吸附，且化学反应在吸附过程中发挥了重要作用。     

When and how to use Q methodology to understand perspectives in conservation research

Understanding human perspectives is critical in a range of conservation contexts, for example, in overcoming conflicts or developing projects that are acceptable to relevant stakeholders. The Q methodology is a unique semiquantitative technique used to explore human perspectives. It has been applied for decades in other disciplines and recently gained traction in conservation. This paper helps researchers assess when Q is useful for a given conservation question and what its use involves. To do so, we explained the steps necessary to conduct a Q study, from the research design to the interpretation of results. We provided recommendations to minimize biases in conducting a Q study, which can affect mostly when designing the study and collecting the data. We conducted a structured literature review of 52 studies to examine in what empirical conservation contexts Q has been used. Most studies were subnational or national cases, but some also address multinational or global questions. We found that Q has been applied to 4 broad types of conservation goals: addressing conflict, devising management alternatives, understanding policy acceptability, and critically reflecting on the values that implicitly influence research and practice. Through these applications, researchers found hidden views, understood opinions in depth and discovered points of consensus that facilitated unlocking difficult disagreements. The Q methodology has a clear procedure but is also flexible, allowing researchers explore long‐term views, or views about items other than statements, such as landscape images. We also found some inconsistencies in applying and, mainly, in reporting Q studies, whereby it was not possible to fully understand how the research was conducted or why some atypical research decisions had been taken in some studies. Accordingly, we suggest a reporting checklist.     

Estimating abundance without recaptures of marked pallid sturgeon in the Mississippi River

Abundance estimates are essential for assessing the viability of populations and the risks posed by alternative management actions. An effort to estimate abundance via a repeated mark‐recapture experiment may fail to recapture marked individuals. We devised a method for obtaining lower bounds on abundance in the absence of recaptures for both panmictic and spatially structured populations. The method assumes few enough recaptures were expected to be missed by random chance. The upper Bayesian credible limit on expected recaptures allows probabilistic statements about the minimum number of individuals present in the population. We applied this method to data from a 12‐year survey of pallid sturgeon (Scaphirhynchus albus) in the lower and middle Mississippi River (U.S.A.). None of the 241 individuals marked was recaptured in the survey. After accounting for survival and movement, our model‐averaged estimate of the total abundance of pallid sturgeon ≥3 years old in the study area had a 1%, 5%, or 25% chance of being <4,600, 7,000, or 15,000, respectively. When we assumed fish were distributed in proportion to survey catch per unit effort, the farthest downstream reach in the survey hosted at least 4.5–15 fish per river kilometer (rkm), whereas the remainder of the reaches in the lower and middle Mississippi River hosted at least 2.6–8.5 fish/rkm for all model variations examined. The lower Mississippi River had an average density of pallid sturgeon ≥3 years old of at least 3.0–9.8 fish/rkm. The choice of Bayesian prior was the largest source of uncertainty we considered but did not alter the order of magnitude of lower bounds. Nil‐recapture estimates of abundance are highly uncertain and require careful communication but can deliver insights from experiments that might otherwise be considered a failure.     

人工湿地基质对NH4＋-N吸附性能

为研究建筑废物红砖和工业废物煤渣用作人工湿地脱氮基质的可行性，分别通过静态吸附实验和动态NHf—N去除效果实验进行考察。结果表明，红砖和煤渣对NH4＋-N最大静态吸附量分别为0．2533mg／g和0．0533mg／g，其吸附等温曲线均符合Freundlich型吸附方程，吸附常数分别为0．0419和0．0091；红砖煤渣组合对污水中NH4＋-N平均动态脱除率达到41．18％，高于红砖的37．63％和煤渣的30．92％。     

受限空间内惰性气体对CH4爆炸抑制特性研究

N2和CO2是常用的惰性抑爆气体,为研究两种气体的抑爆特性,采用20L球形爆炸试验装置,分析了不同浓度配比条件下N2/CH4/空气以及CO2/CH4/空气混合气体的爆炸压力,同时采集爆炸后的气体样品,对比分析爆炸后残留气体的主要成分。结果显示:随CH4浓度从5%增加至12.5%时,完全抑制CH4爆炸需要的惰性气体最小量先增大后降低,CH4浓度在6.5%~7.5%之间时,抑爆需要的惰性气体的量最大;在同一CH4浓度条件下,抑爆需要N2的量大于CO2,并且CH4浓度在5%~6.5%时,抑爆需要两种惰性气体的量值差别最大;当CH4浓度一定时,随着加入惰性气体量的增大,爆炸最大超压逐渐降低,惰性气体浓度和爆炸超压之间基本呈线性关系;在同样条件下,相对于N2,CO2为抑爆气体时,爆炸后腔体内残留的CH4浓度较高。研究成果为惰性气体抑爆技术提供技术支撑,同时为揭示惰性气体抑爆机理有一定作用。     

羟基乙叉二膦酸镀铜废液的处理及Cu~(2+)的高附加值资源化回收

采用Na BH4还原法将羟基乙叉二膦酸(HEDP)镀铜废液中的Cu~(2+)制备成纳米铜粉,并采用聚丙烯酰胺(PAM)对还原反应后的废液进行絮凝处理。研究了n(Cu~(2+))∶n(Na BH4)、还原反应温度、还原反应时间及PAM添加量对废液中剩余Cu~(2+)质量浓度的影响,并对回收的纳米铜粉进行了XRD和TEM表征。实验结果表明:当n(Cu~(2+))∶n(Na BH4)=4∶6、还原反应温度为50℃、还原反应时间为2 h时,废液中剩余Cu~(2+)质量浓度降低至1.1 mg/L,Cu~(2+)还原率达99.99%;可获得粒径为20~45 nm的近球型、高纯度、由多晶组成的纳米铜粉;当PAM添加量为10 mg/L时,废液中剩余Cu~(2+)质量浓度降至0.35 mg/L以下,达到GB 21900—2008《电镀污染物排放标准》(小于0.5 mg/L)的要求。     

有机改性成都粘土预处理垃圾渗滤液

以成都粘土为原料,十六烷基三甲基溴化铵(HDTMA)为改性剂制备有机改性土,并将其应用于垃圾渗滤液的预处理。采用单因素静态吸附实验,以粘土对垃圾渗滤液COD和氨氮的去除率作为考查指标,初步探究有机改性土预处理垃圾渗滤液的适宜条件;并对有机改性粘土及原土进行性能表征,初步分析其吸附机理。研究结果表明,有机土的处理效果明显优于原土,处理效果上比原土提高了1.6~2.3倍;有机土预处理垃圾渗滤液适宜条件为:投加量120 g/L、搅拌速度200 r/min、搅拌时间50 min、pH=7、静置时间为6 h。     

外加微量N2H4下SBR中硝化微生物特性

运行实验室规模单级硝化序批式反应器(SBR),研究长期外加微量N_2H_4(约3 mg·L~(-1))对硝化污泥中功能微生物好氧氨氧化菌(AOB)、亚硝酸盐氧化菌(NOB)的影响.结果表明,外加微量N_2H_4的硝化污泥中,AOB主要属于亚硝化球菌(Nitrosococcu)属和亚硝化单胞菌(Nitrosomonas)属,另有少部分属于亚硝化螺旋菌(Nitrosospira)属,NOB属于硝化杆菌(Nitrobacter)属.外加微量N_2H_4前后,AOB amoA基因拷贝数(以干污泥计)由1.0×10~9copies·g~(-1)减少为2.09×10~4copies·g~(-1),NOB nxrB基因拷贝数由1.28×10~7copies·g~(-1)减少为2.56×10~5copies·g~(-1).AOB对环境因素较NOB相比更为敏感,N_2H_4对硝化微生物的抑制与毒性作用使外加微量N_2H_4的硝化污泥中AOB流失幅度大于NOB,但定量PCR方法无法准确比较N_2H_4对AOB与NOB活性抑制的强弱.长期外加微量N_2H_4破坏硝化微生物活性,使反应器崩溃.因此在没有厌氧氨氧化菌(AnAOB)消耗N_2H_4的亚硝化系统中,企图通过调控外加N_2H_4浓度水平抑制NOB活性,从而进一步洗脱NOB提高脱氮性能可能无法实现.