青岛大气气溶胶中游离氨基化合物的浓度、组成和来源

氨基化合物是大气气溶胶中一类重要的有机氮化合物,由于其具有吸湿性,且沉降入海后可被海洋浮游生物直接利用,因此,可能在大气化学方面和海洋生态系统中具有重要作用.基于此,本研究利用2007年6月至2008年5月在青岛采集的55个总悬浮颗粒物样品,采用邻苯二甲醛/N-乙酰-L-半胱氨酸柱前衍生高效液相色谱法,分析了其中游离氨基化合物(FAC)的浓度.结果表明,气溶胶中总FAC浓度为0.14~8.33 nmol·m^-3,其中,精氨酸、甲胺和丙氨酸的贡献最大.不同季节FAC的组成不同,精氨酸在夏、秋季节对FAC的贡献高于冬、春季节,甲胺的相对贡献则在夏季较低,而冬、春季较高.采样期间气团来源和天气状况的不同会影响气溶胶中FAC的浓度和组成.FAC在受南方陆源影响的气溶胶中浓度最高,北方陆源次之,海洋源气溶胶中的浓度最低,蛋白质类氨基化合物对总FAC的贡献在海洋源气溶胶中最高,在南方陆源气溶胶中最低.雾天和烟霾时气溶胶中FAC的浓度分别为晴天时的2.5倍和1.8倍,沙尘天气时FAC浓度与晴天时基本相当,蛋白质类氨基化合物对总FAC的贡献在晴天和雨后相对较高,在烟霾和雾天时相对较低.     

连续进水对好氧颗粒污泥稳定维持的影响

为了考察连续进水对好氧颗粒污泥稳定维持的影响,在SBR反应器中接种成熟的好氧颗粒污泥,采用连续进水、间歇出水的方式运行.在反应器运行过程中,部分好氧颗粒污泥解体,完整存在的好氧颗粒污泥表面附着生长树枝状污泥和少量丝状菌.SVI在最初的13d内逐步上升,随后趋于稳定.同时,考察了好氧颗粒污泥在连续进水运行过程中EPS含量的变化以及EPS的空间分布变化:胞外多糖的含量在运行过程中呈下降趋势;胞外蛋白的含量整体呈先上升后下降的趋势;反应器运行15d后,胞外蛋白和胞外多糖的含量趋于稳定.连续进水运行30d后,EPS空间分布最大变化是β-D吡喃葡萄糖,它大量聚集在颗粒的表层及颗粒中伸出的树枝状污泥及丝状菌的表层.本研究表明,连续进水的运行方式不利于好氧颗粒污泥的稳定维持,底物浓度梯度为好氧颗粒污泥稳定维持的重要因素之一;EPS的分泌量以及空间分布对好氧颗粒污泥的形成及其稳定维持起着至关重要的作用.     

基于三角模糊数和重金属化学形态的土壤重金属污染综合评价模型

将三角模糊数理论引入环境评价领域,构建了量化表征不同重金属自身生物毒性及同一重金属不同化学存在形态生物毒性的土壤重金属生物毒性双权重评价体系,并结合地累积指数评价模型,建立了土壤重金属污染综合评价模型.最后,采用该综合评价模型评价了寺庄顶典型污灌区的土壤重金属污染状况.评价结果表明,寺庄顶典型污灌区土壤中5种重金属的综合污染评价值差异较大,各重金属的综合污染程度排序为:Cd＞Ni＞Cu＞Zn＞Cr,Cd、Ni、Cu应成为今后该地区土壤污染治理的主要控制因子.与确定性模型评价结果的对比分析表明,综合评价模型较好地弥补了确定性评价的不足,并能更全面、真实地综合表征评价区域土壤重金属富集污染和潜在生物毒性风险信息,为科学决策提供了理论基础.     

微波加热再生废弃的净化石油化工废水活性炭

为了对石油化工废水净化处理后的废弃活性炭实现循环利用,提出了在无保护气体和活化气体条件下进行微波加热的方法。主要评估了再生温度和再生时间对再生活性炭的吸附性能和得率的影响。结果表明,在再生温度为600℃,再生时间为15 min时,活性炭的碘吸附能力达到最大值971 mg/g,得率为82.36%。再生活性炭比表面积高达1 028m2/g,总孔体积为1.23 m L/g,平均孔径为4.89 nm。通过废弃活性炭和再生活性炭进行了SEM对比分析,再生活性炭表面杂质减少,孔隙数量明显增多。     

Clusters of community exposure to coastal flooding hazards based on storm and sea level rise scenarios—implications for adaptation networks in the San Francisco Bay region

Regional Environmental Change - Sea level is projected to rise over the coming decades, further increasing the extent of flooding hazards in coastal communities. Efforts to address potential...     

Development of rearing and testing protocols for a new freshwater sediment test species: the gastropod Valvata piscinalis

This paper aimed at proposing rearing and testing protocols for Valvata piscinalis, a new potential species for sediment toxicity testing. Such tests were developed since this species reliably represents the bio/ecological characteristics of other gastropods. It may thus be representative of their sensitivity to chemicals. V. piscinalis was successfully cultured in our laboratory for six generations. Cultures provided a high productivity for a low working time and low costs. The tests conditions we proposed seemed to be relevant for the development of reliable tests with this species. Indeed, hatching probability of egg-capsules, as well as embryo, newborn and juvenile survival rates, were close to 100%. Moreover, growth rates and fecundity were significantly higher than in field and in other laboratory studies. Partial life-cycle tests on clean sediments were achieved for various feeding levels to determine survival, growth and reproduction patterns, ad libitum feeding level and life cycle parameters values. Ad libitum feeding levels for newborn, juveniles and adults were 0.1, 0.4 and 0.8 mg Tetramin/individual/working day. Growth tests with zinc-spiked sediments provided a no-effect concentration and a lowest effect concentration of respectively 200 and 624 mg zinc/kg dry sediment. Other growth tests on spiked sediments we ran at our laboratory with second, third and fourth instars larvae of Chironomus riparius pointed out that V. piscinalis was more sensible to zinc than the chironomid, which is a routine test species in ecotoxicology. According to these results, V. piscinalis is a promising candidate species for sediment toxicity testing.     

改进SBR工艺运行方式强化脱氮除磷的效果

由于传统序批式活性污泥法SBR处理工艺的局限性,当要求同时进行有机物、氮和磷的去除时,基本的运行方式虽在有机物的去除方面可达到较为满意的处理效果,但难以达到满意的脱氮除磷效果.通过对SBR法运行工况分析后提出了兼有脱氮功能、除磷功能及同时具备脱氮除磷功能的3种不同运行方式的改进流程,从而在不改变原有SBR反应池主体结构的基础上可满足不同尾水排放标准的要求.     

Knowledge co‐production and boundary work to promote implementation of conservation plans

Knowledge co‐production and boundary work offer planners a new frame for critically designing a social process that fosters collaborative implementation of resulting plans. Knowledge co‐production involves stakeholders from diverse knowledge systems working iteratively toward common vision and action. Boundary work is a means of creating permeable knowledge boundaries that satisfy the needs of multiple social groups while guarding the functional integrity of contributing knowledge systems. Resulting products are boundary objects of mutual interest that maintain coherence across all knowledge boundaries. We examined how knowledge co‐production and boundary work can bridge the gap between planning and implementation and promote cross‐sectoral cooperation. We applied these concepts to well‐established stages in regional conservation planning within a national scale conservation planning project aimed at identifying areas for conserving rivers and wetlands of South Africa and developing an institutional environment for promoting their conservation. Knowledge co‐production occurred iteratively over 4 years in interactive stake‐holder workshops that included co‐development of national freshwater conservation goals and spatial data on freshwater biodiversity and local conservation feasibility; translation of goals into quantitative inputs that were used in Marxan to select draft priority conservation areas; review of draft priority areas; and packaging of resulting map products into an atlas and implementation manual to promote application of the priority area maps in 37 different decision‐making contexts. Knowledge co‐production stimulated dialogue and negotiation and built capacity for multi‐scale implementation beyond the project. The resulting maps and information integrated diverse knowledge types of over 450 stakeholders and represented >1000 years of collective experience. The maps provided a consistent national source of information on priority conservation areas for rivers and wetlands and have been applied in 25 of the 37 use contexts since their launch just over 3 years ago. When framed as a knowledge co‐production process supported by boundary work, regional conservation plans can be developed into valuable boundary objects that offer a tangible tool for multi‐agency cooperation around conservation. Our work provides practical guidance for promoting uptake of conservation science and contributes to an evidence base on how conservation efforts can be improved.     

Environmental effects of heavy metals derived from the e-waste recycling activities in China: A systematic review

As the world’s leading manufacturing country, China has become the largest dumping ground for e-waste, resulting in serious pollution of heavy metals in China. This study reviews recent studies on environmental effects of heavy metals from the e-waste recycling sites in China, especially Taizhou, Guiyu, and Longtang. The intensive uncontrolled processing of e-waste in China has resulted in the release of large amounts of heavy metals in the local environment, and caused high concentrations of metals to be present in the surrounding air, dust, soils, sediments and plants. Though the pollution of many heavy metals was investigated in the relevant researches, the four kinds of heavy metals (Cu, Pb, Cd and Cr) from e-waste recycling processes attracted more attention. The exceedance of various national and international standards imposed negative effects to the environment, which made the local residents face with the serious heavy metal exposure. In order to protect the environment and human health, there is an urgent need to control and monitor the informal e-waste recycling operations.     

应用蒸汽相变促进WFGD系统脱除细颗粒的技术分析

依据蒸汽相变促进细颗粒凝并长大的机理及典型的湿法烟气脱硫(WFGD)工艺特征,提出脱硫塔出口设置蒸汽相变室,以建立细颗粒凝结长大所需要的过饱和环境,进而提高WFGD系统对细颗粒的脱除效率.综合WFGD系统的腐蚀机理及水汽不易在低表面能材料表面凝结的特性,提出采用具有良好耐腐蚀性能的低表面能材料作为凝结室的内壁面或壁面衬...