Sphaerotilus natans对Zn~(2+)吸附的研究

以球衣菌作为生物吸附剂,研究了球衣菌对Zn2+吸附过程中的影响因素,包括吸附时间,pH,菌龄等。结果表明:Zn2+浓度为1.0mg/L,菌体浓度为0.5g/L,菌龄32h,pH7.0,吸附时间30min时,吸附的效果最好,吸附率达到77.2%,吸附量为3.86mg/g。吸附作用是一个快速的过程,30min就基本达到平衡。     

反硝化聚磷菌的富集及富集污泥活性研究

依据DPB原理,利用SBR动态反应器和静态释/聚磷装置。以A2/O厌氧段污泥为种泥,进行以硝酸盐为电子受体的反硝化聚磷菌的富集,并对富集有反硝化聚磷菌的污泥进行了反硝化聚磷活性性能考察。结果表明,利用硝酸盐为电子受体的反硝化聚磷菌存在于A2/O厌氧段污泥中,反硝化聚磷菌占总聚磷菌的比例为23%,该种污泥可作为反硝化聚磷工艺的种泥;由于常规的聚磷菌被淘汰聚磷菌的数量由6.8×107个/mL减少到1.1×103个/mL,但通过选择和富集聚磷菌总数由1.1×103个/mL增加到8.2×104个/mL,且反硝化聚磷菌占聚磷菌总数的比例也由23%提高到94%,磷酸盐去除率由最初的9.86%上升到95.2%,出水磷酸盐的浓度为0.79mg/L;通过改变进水中不同磷酸盐浓度验证体系处于稳定状态。     

陶瓷填料上TiO_2薄膜光催化降解甲苯的研究

在陶瓷填料上负载了P25纳米TiO2,对薄膜的制备和甲苯蒸汽在薄膜上的光催化降解进行了研究。在制备过程中得出如下结论:通过增加浸渍-提拉的次数来提高甲苯降解率的方法是有限的,采用长时间的浸渍或者采用自制粘结剂作下涂层都能大幅度提高甲苯的降解率,甲苯的降解率随镀膜量的增加而增加;在光催化过程中得出如下结论:甲苯的降解率随着湿度的增加而增加,随着甲苯初始浓度的增加而减小;甲苯的降解所需要的光强是一定的,在一定的范围内,甲苯的降解率随着光强的增大而增大,但是超过这个范围的过大的光强并不能提高甲苯的降解率,对于相同的光强,254 nm紫外光的降解率远大于365 nm紫外光的降解率。     

Impacts of climate change and CO2 increase on agricultural production and adaptation options for Southern Québec, Canada

This study involves the assessment of the potential impacts of greenhouse gas climate change and changing ambient carbon dioxide (CO₂) levels on crop yields in Quebec, Canada. The methodology involves coupling the transient diagnostics of two Atmosphere-Ocean General Circulation Models, namely the Canadian CGCM1 and the British HadCM3, to the Decision Support System for Agrotechnology Transfer (DSSAT) 3.5 crop models to simulate current (1961–1990) and future (2040–2069) crop yields and changes. This is done for four different crop species, namely spring wheat, maize, soybean, and potato, and for seven agricultural regions of Southern Quebec. The results of this study focus on the main causative factors influencing crop yields, namely the direct CO₂ fertilization effect, the influence of the increase in growing season temperature, including optimal thermal conditions and acceleration in crop maturation, soil moisture availability, as influenced by precipitation and evapotranspiration, and nitrogen uptake by crops. Our results show that crop yield changes may vary according to climate scenario, crop species, and agricultural region. Consistent with other similar research, it would seem that these multiple causative factors very often seem to cancel each other out and dilute the impacts of climate change on crop yields.     

N2填充对船舶压载水中浮游生物的影响研究

实验研究了N2对于船舶压载水中浮游生物生长的影响,旨在探讨利用船舶惰气系统抑止或灭除船舶压载水中浮游生物的可能性.实验结果表明,由N2形成的惰性气体保护层能够对压载水中的生物的生长起到明显的抑止和部分致死的效果.同时实验对比研究了N2填充作为电解法处理船舶压载水的前处理与直接电解对压载水中生物灭除的效果,表明N2填充提高了电解法处理船舶压载水的处理效果.     

一种改性柱撑蒙脱石的制备及其对废水中SO2-4吸附效率研究

蒙脱石具有较大的比表面积和阳离子交换容量,吸附性能较好.但其不能有效地吸附疏水性物质,应用中常将一些聚合羟基金属阳离子引入到蒙脱石层间制成柱撑蒙脱石以提高其孔道特性和热稳定性.为了进一步提高其吸附效率,在柱撑蒙脱石中加入了物料A,高温焙烧,对其进行了一系列的改性,并确定了改性条件,制备了一种新型的SO2-4高效吸附剂,并应用于煤矿矿井废水的治理,改性后的吸附剂较柱撑蒙脱石对水中SO2-4的吸附率提高了54.6%.最佳焙烧温度为800℃,焙烧时间为4 h,焙烧的最佳物料配比为1:4.     

Influence of environmental temperature and relative humidity on photocatalytic oxidation of toluene on activated carbon fibers coated TiO2

TiO₂ supported on active carbon fiber (TiO₂/ACF), an absorbable photocatalyst, is a new kind of material applied in air purification. In this paper, the influence of environmental temperature (T) and relative humidity (RH) on the gas-solid adsorption of toluene and the photocatalytic oxidation (PCO) efficiency of adsorbed toluene on TiO₂/ACF were studied, and then, the purification capability of TiO₂/ACF was estimated. PCO results showed that although the PCO efficiency increased under high RH and T levels, the amount of adsorption of toluene decreased. Moreover, quantitative analysis results of intermediates indicated that more environmental risk emerged when PCO of toluene was carried out at higher environmental T and RH levels because more toxic intermediates would be accumulated on the TiO₂/ACF. So, it is significant to control the environmental T and RH conditions in the application of the PCO technique. T = 25°C and RH530% is the optimal condition for purifying toluene in our experimental system. __________ Translated from Urban Environment & Urban Ecology, 2007, 20(5): 10–13 [译自: 城市环境与城市生态]     

国际城市CO2排放清单研究进展及评述

综述和分析了国际城市CO2排放清单研究进展,及国际组织/机构建立的城市清单标准和协议.将城市清单方法划分为直接排放法、碳足迹法和直接-间接排放混合法,并比较分析了各种方法的特点和优劣势.探讨了城市清单中范围3的内容和计算深度及城市交通排放分配问题.早期城市排放清单基本沿用国家清单方法,但当城市作为消费者的特色愈加明显,其清单方法学受城市物质循环思想的影响,已经不同于国家清单方法并逐渐成熟.在准确性、公平性和效率性原则下,直接-间接排放混合法成为城市清单的主流方法,当前排放主要包括范围1+范围2,但未来范围1+范围2+范围3(重点产品和服务)将成为主流趋势.城市清单中范围3的标准化和可操作性问题,及城市交通分配方法的统一和规范是近期城市清单研究的重点和难点.城市CO2排放监测将会成为城市清单的重要支撑,其作为独立数据源将在城市清单的可测量、可报告、可核查中会发挥重要作用.     

Empirically Analysis of the CO2 Emissions Embodied in Exports of China

Abstract

In this paper, using the input-output model, the author first calculated the CO₂ emissions embodied in exports of China in 2002 and 2007. Then, the author empirically analyzed problems existing in the composition of exported products and analyzed its possible reasons. The research results of this paper are as follows: Since China’s entry into WTO, the CO₂ emissions embodied in exports of China have been increasing rapidly; the value of exported products of high-carbon emissions industries accounts for a relatively higher proportion to China’s total exports value because China’s carbon intensive products have a certain competitive advantage. Additionally, this paper has put forward relevant suggestions based on these results.     

基于地统计模型的上海大气污染物多建模方法的比较

地统计模型被广泛应用于环境空气污染物暴露模拟,但不同建模方法及其模拟结果之间的对比研究较少.基于上海2016~2019年55个环境空气监测点位的NO₂和PM_2.5观测数据,以及交通路网、排放源兴趣点和卫星数据等地统计变量,应用偏最小二乘回归（PLS）、监督学习线性回归（SLR）和机器学习随机森林（RF）这3种建模方法创建年暴露模型,并进一步应用普通克里金插值（OK）法分析模型残差,构建复合模型.应用交叉验证对模型的模拟效果进行检验,选取每一种建模方法的最优模型结构（是否应用OK）作为最终模型.结果表明,NO₂模型中表现最好的是RF-OK （R_mse²为0.70~0.82）和PLS-OK模型（R_mse²为0.78~0.84）;PM_2.5模型中PLS模型（R_mse²为0.62~0.71）优于SLR-OK （R_mse²为0.40~0.79）和RF-OK （R_mse²：0.31~0.56）模型.应用3种建模方法对上海1 km网格开展年暴露模拟和对比,NO₂模型间模拟结果的相关性（r为0.82~0.91）高于PM_2.5模拟结果的相关性（r为0.66~0.96）.基于3种模型2019年的模拟结果,评估了上海NO₂和PM_2.5的人群暴露水平.