大气气溶胶中元素种态研究

应用化学逐级提取流程对国际原子能机构（简称IAEA）气溶胶、室内和室外气溶胶、煤飞灰中元素的组成和种态进行了分析，应用仪器中子活化法测定了各种态中元素的含量，计算出元素在各种态中的分配比例。按照气溶胶中元素不同种态的环境和生物活性以及主要来源来分类，评述了元素在环境和生态系统中的吸收和转化能力，并对气溶胶中元素对环境的影响作出了初步的探讨。实验数据表明，气溶胶中的不同元素在各种态中的分布是有差异的。地壳来源元素中，Sc,Al,Fe和Ti主要分布在不溶物态中，稀土元素主要分布在氧化物态和不溶物态；不溶物态沉降到地表后不易进行迁移和转化，对环境的影响较小；氧化物态性质比较活泼，可以在大气中发生化学反应。Mn在气溶胶中主要分布在水可溶态和氧化物态，环境可交换性要比Al,Fe,Ti等大得多。人为来源元素的环境可交换态的比例都比较高，这说明它们通过干、湿清除过程沉降到地表后，水可溶态可以直接进入水循环；碳酸盐、氧化物和有机物态可以在适当的条件下与环境中的其他物质发生化学反应，生成易溶于水的化合物进入生态环境中，对环境影响较大。     

Degradation of antipyrine in the Fenton-like process with a La-doped heterogeneous catalyst

A La-doped Co-Cu-Fe catalyst was synthesized for the antipyrine (ANT) removal. The La-doped catalyst had higher ANT removal than the control (95% vs. 54%). La reduced the particle size and increased the specific surface area of catalyst. The aim of this study was to synthesize a novel lanthanum (La) doped catalyst and to investigate antipyrine removal in wastewater using the Fenton-like process with the catalyst. The La-doped Co-Cu-Fe catalyst was synthesized using the modified hydrothermal method. Results showed that the La-doped catalyst had higher specific surface area and lower particle size than the catalyst without La doping (i.e., the control) (267 vs. 163 m²/g and 14 vs. 32 nm, respectively). Under the conditions of catalyst dosage 0.5 g/L, H₂O₂ concentration 1.70 g/L, and NaHCO₃ 0.1 g/L, the antipyrine removal within 60 min using the Fenton-like process with the La-doped catalyst was much higher than that with the control (95% vs. 54%). The hydroxyl radical concentration with the La-doped catalyst within 60 min was two times higher than that with the control (49.2 vs. 22.1 mg/L). The high catalytic activity of La-doped catalyst was mainly attributed to its high specific surface area based on the X-ray photoelectron spectroscopy result. Our La-doped catalyst should have great potential to remove antipyrine in wastewater using the heterogeneous Fenton-like process.     

冰雪灾害中交通工程的损害类型及原因分析

通过对已建及在建的高速公路在冰灾中的损害调查,详细列出了损害的类型并进行了原因分析。并将此次灾难中暴露出的设计、施工和管理方面的问题进行了分解。     

CS2在TiO2表面的多相光化学反应研究

本文运用原位漫反射红外光谱(DRIFTS)、GC、XPS等手段研究了CS2在大气半导体颗粒TiO2表面的多相光化学反应.结果表明在模拟太阳光照射下,低浓度的CS2(8.1 mg·m(-3))在TiO2:表面发生多相光化学反应,生成气态产物cos、H2S、SO2,进而在颗粒物表面生成硫酸盐.在氧气体积浓度为21%,氙灯照...     

低温低浊微污染水源水预氧化处理工艺设计

选用预氧化处理工艺以提高混凝絮凝效果,减少停留时间从而实现在小型设备中较高的处理量;占地面积小且速度快的气浮池代替了普通的沉淀池,并在混凝沉淀处理药剂和消毒处理药剂上选择了在低温条件下效果好的.     

Fe(Mn)OOH催化臭氧氧化水中扑米酮和溶解性有机物(DOMs)

使用碱式共沉淀法成功制备Fe(Mn)OOH催化剂,并且证实Fe(Mn)OOH可以高效催化臭氧降解水中扑米酮(PMD)和溶解性有机物(DOMs).表征分析表明,Fe(Mn)OOH表现出α-FeOOH和MnFe_2O_4两相的特征晶相结构.在相同条件下,Fe(Mn)OOH催化臭氧体系比单独臭氧、MnFe_2O_4和FeOOH催化臭氧体系表现出更好的扑米酮降解效能.在20 min时,Fe(Mn)OOH催化臭氧体系可以降解去离子水中97.5%的扑米酮,并且在快速和慢速反应阶段的反应速率常数分别可达0.46044 min~(-1)和0.10723 min~(-1).结果还表明,初始扑米酮和臭氧浓度以及催化剂投量之间的配比关系可能对扑米酮的降解有重要影响.Fe(Mn)OOH催化体系遵循羟基自由基的反应机制,可能是通过促进臭氧快速分解产生大量的羟基自由基,进而提高了水中有机物的降解效能.此外,Fe(Mn)OOH还具有结构稳定,可重复利用性好的优势.     

A case study of development and application of a streamlined control and response modeling system for PM2.5 attainment assessment in China

This article describes the development and application of a streamlined air control and response modeling system with a novel response surface modeling-linear coupled fitting method and a new module to provide streamlined model data for PM_(2.5) attainment assessment in China.This method is capable of significantly reducing the dimensions required to establish a response surface model,as well as capturing more realistic response of PM_(2.5) to emission changes with a limited number of model simulations.The newly developed module establishes a data link between the system and the Software for Model Attainment Test—Community Edition(SMAT-CE),and has the ability to rapidly provide model responses to emission control scenarios for SMAT-CE using a simple interface.The performance of this streamlined system is demonstrated through a case study of the Yangtze River Delta(YRD) in China.Our results show that this system is capable of reproducing the Community Multi-Scale Air Quality(CMAQ) model simulation results with maximum mean normalized error 3.5%.It is also demonstrated that primary emissions make a major contribution to ambient levels of PM_(2.5) in January and August(e.g.,more than50%contributed by primary emissions in Shanghai),and Shanghai needs to have regional emission control both locally and in its neighboring provinces to meet China's annual PM_(2.5)National Ambient Air Quality Standard.The streamlined system provides a real-time control/response assessment to identify the contributions of major emission sources to ambient PM_(2.5)(and potentially O_3 as well) and streamline air quality data for SMAT-CE to perform attainment assessments.     

Design and demonstration of a next-generation air quality attainment assessment system for PM2.5 and O3

Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test—Community Edition (SMAT-CE) is developed for demonstrating attainment of air quality standards of O₃ and PM_2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards (NAAQS) shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM_2.5 and 8-hour O₃ for a proposed emission control policy.     

Design and demonstration of a next-generation air quality attainment assessment system for PM2.5 and O3

Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test—Community Edition (SMAT-CE) is developed for demonstrating attainment of air quality standards of O₃ and PM_2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards (NAAQS) shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM_2.5 and 8-hour O₃ for a proposed emission control policy.