城市污泥及落叶蚯蚓处理最优条件因子实验研究

蚯蚓的环境生态作用具有促进微生物和其他土壤动物活动、消化分解土壤中重金属的功能,并且能够破碎与分解枯落物。通过城市污泥和城市落叶发酵后建立起蚯蚓养殖基床,以赤子爱胜蚓为主体,通过蚯蚓对污泥中重金属的富集作用实现城市污泥无害化,达到城市污泥与落叶资源化的目的。通过设计四因子四水平正交试验探索赤子爱胜蚓处理城市污泥及落叶的最优条件组合。实验结果表明:在落叶添加比例为35%,蚓床湿度为75%,培养温度为14℃,饲养密度为32mg/g时,赤子爱胜蚓对城市污泥和落叶的处理指标达到峰值,蚯蚓床对于污泥中重金属Cu和Zn的富集量分别为274.32μg/箱和420.98μg/箱,处理效果最佳。     

离子色谱法测定PM_(2.5)中水溶性无机阴离子

为确定PM2.5中水溶性无机阴离子的含量,本文采用戴安ICS900离子色谱仪对F-、Cl-、NO-2、NO-3、SO2-4进行测量,实验表明,这种测量方法操作简单、测量结果准确度高、测量速度快,能同时测定多种水溶性无机阴离子。     

Social capital and food security in post-conflict rural Lira District,northern Uganda

While a strong relationship has been established between social capital and food security in the research literature, it is uncertain whether this holds in post-conflict situations. This study examines associations between social capital and food security in post-conflict Lira District, northern Uganda. Since factors affecting food security are complex, we explored the roles of households' characteristics in food security outcomes. Data were collected from March to July 2011 through face-to-face interviews with 221 heads of household in rural Lira. Using multinomial logistic regression, a strong positive association was identified between social capital and household food security. The study also found significant associations of food security with sex, education of household head, amount of cultivated land, and farm and home possessions. The results of this analysis can aid the design of food security programmes that empower poor people while targeting the most vulnerable groups, thereby promoting sustainable development in post-conflict communities.     

基于系统基模的甘肃白银“5·22”越野马拉松事件分析*

为系统研究越野马拉松产业快速发展背后的安全问题,以甘肃白银“5·22”越野马拉松事件为例,采用系统基模工具,构建“5·22”越野马拉松事件系统中企业方、政府方和个体方3方主体行为模式的因果循环回路,并进行系统致因分析。研究结果表明:“5·22”越野马拉松事件是运营企业、政府职能部门、参赛者和志愿者行为逻辑偏差造成共同回应机制失衡的结果,基于此提出同类事件中主体因素的长期杠杆解,为企业安全文化建设、制定相匹配的安全保障制度和完善的个体组织参与机制,指出要解决安全问题必须降低杠杆解的时滞效应,实现杠杆解之间的正反馈机制。     

应用PART5模式计算机动车尾气管的颗粒物排放

采用修正的PART5模式获得了北京市机动车尾气管的颗粒物(PM10和PM2.5)排放因子.在此基础上,计算了北京市1995和1998年机动车PM10和PM2.5的排放总量,并确定了分车型的排放分担率和颗粒物中各组分(铅、硫酸盐、可溶性有机物和残余碳等)的比例.结果表明,北京市机动车PM10和PM2.5的平均排放因子很高,其中汽油车、摩托车和重型柴油车的排放因子分别是美国同期水平的1.7～8.6倍、2.1～3.5倍和1.3～1.5倍.1995年北京市机动车尾气管排放的PM10和PM2.5分别为2445t和1890t,1998年则分别增至3359t和2694t,增加的幅度为37.4%和42.5%.     

Simultaneous removal of NOx and chlorobenzene on V2O5/TiO2 granular catalyst: Kinetic study and performance prediction

• A V₂O₅/TiO₂ granular catalyst for simultaneous removal of NO and chlorobenzene. • Catalyst synthesized by vanadyl acetylacetonate showed good activity and stability. • The kinetic model was established and the synergetic activity was predicted. • Both chlorobenzene oxidation and SCR of NO follow pseudo-first-order kinetics. • The work is of much value to design of multi-pollutants emission control system. The synergetic abatement of multi-pollutants is one of the development trends of flue gas pollution control technology, which is still in the initial stage and facing many challenges. We developed a V₂O₅/TiO₂ granular catalyst and established the kinetic model for the simultaneous removal of NO and chlorobenzene (i.e., an important precursor of dioxins). The granular catalyst synthesized using vanadyl acetylacetonate precursor showed good synergistic catalytic performance and stability. Although the SCR reaction of NO and the oxidation reaction of chlorobenzene mutually inhibited, the reaction order of each reaction was not considerably affected, and the pseudo-first-order reaction kinetics was still followed. The performance prediction of this work is of much value to the understanding and reasonable design of a catalytic system for multi-pollutants (i.e., NO and dioxins) emission control.     

Preparation of nZVI embedded modified mesoporous carbon for catalytic persulfate to degradation of reactive black 5

• The MCNZVI is prepared as an interesting material for PS activation. • Graphitized carbon shells facilitate electron transfer from Fe⁰. • The MCNZVI exhibits excellent performance to degrade RB5 by ¹O₂. • The MCNZVI has high stability and reusability in the oxidation system. High-efficiency and cost-effective catalysts with available strategies for persulfate (PS) activation are critical for the complete mineralization of organic contaminants in the environmental remediation and protection fields. A nanoscale zero-valent iron-embedded modified mesoporous carbon (MCNZVI) with a core-shell structure is synthesized using the hydrothermal synthesis method and high-temperature pyrolysis. The results showed that nZVI could be impregnated within mesoporous carbon frameworks with a comparatively high graphitization degree, rich nitrogen doping content, and a large surface area and pore volume. This material was used as a persulfate activator for the oxidation removal of Reactive Black 5 (RB5). The effects of the material dosage, PS concentration, pH, and some inorganic anions (i.e., Cl⁻, SO₄²⁻) on RB5 degradation were then investigated. The highest degradation efficiency (97.3%) of RB5 was achieved via PS (20 mmol/L) activation by the MCNZVI (0.5 g/L). The pseudo-first-order kinetics (k = 2.11 × 10⁻² min⁻¹) in the MCNZVI/PS (0.5 g/L, 20 mmol/L) was greater than 100 times than that in the MCNZVI and PS. The reactive oxygen species (ROS), including ¹O₂, SO₄^·−, HO^·, and ·O₂⁻, were generated by PS activation with the MCNZVI. Singlet oxygen was demonstrated to be the primary ROS responsible for the RB5 degradation. The MCNZVI could be reused and regenerated for recycling. This work provides new insights into PS activation to remove organic contamination.     

带有阶跃函数的GIM（1）预测模型及其应用

结合某水域地面水ＲＯＤ５的预测实践,研究提出了带有阶跃函数的ＧＩＭ（１）预测模型,并给出了估计这种模型参数的简便方法,从而扩大了ＧＩＭ（１）模型在环境系统中的应用范围,实例表明,运用该方法得到的模型比常规ＧＩＭ（１）具有更高的精度。     

新试剂5—（3—甲基—2—吡啶）亚甲基若丹宁光度法测定汞的研究

研究了新试剂5-（3-甲基-2-毗啶）亚甲基若丹宁（MPMR）与汞的显色反应,在弱酸性介质中和CTMAB微乳液存在下,MPMR与Hg2 生成2：1稳定络合物,λmax=445nm,ε=1.04X105L.mol－1.cm－1。汞的含量在0～1．2mg几内符合比耳定律。方法用于水样中汞的测定,结果满意。     

Human–environment interactions: towards synthesis and simulation

Leaders of the PAGES Focus 5 programme ‘Past Ecosystem Processes and Human–Environment Interactions’ identify key issues for research on human–environment interactions for wider discussion. These include the need for long-term perspectives, the opportunities for maximising palaeoenvironmental research, the need for integration and regionalisation and the challenge of developing dynamic simulation models. A new organisational matrix for regional studies is outlined, based on a series of zonal/azonal regions and on the degree of human impact. Future priorities for palaeoenvironmental research include new studies in degraded human-dominated landscapes, highly-valued ecosystems and sites relevant to other IGBP Core Projects. Simulation of future human–environment interactions using modelling approaches that have been tested against long records lags behind global climate modelling, but cellular approaches for biogeophysical and multi-agent systems show promise.