CNTs-CeO_2/H_2O_2复合光催化氧化体系降解水中酸性橙Ⅱ

运用"化学沉淀法",将Ce O2负载到碳纳米管(CNTs)上制备复合光催化剂,采用"单因素实验法"优化了制备条件。运用透射电镜和X射线衍射仪对复合光催化剂进行了表征。结果表明,负载到CNTs上的Ce O2为多晶面心立方结构,尺寸大小在6~10 nm之间,其在CNTs上分散效果好,负载均匀且负载率高。在溶液p H为5,CNTs-Ce O2用量为0.50g/L并光照2 h后,酸性橙Ⅱ的光脱色率和TOC去除率分别达到64.71%和44.25%;加入0.02 mmol/L H2O2后,CNTsCe O2/H2O2复合体系对酸性橙Ⅱ的光脱色率和TOC去除率分别提高至91.35%和82.40%。这预示着CNTs-Ce O2/H2O2复合光催化氧化体系在对水中偶氮染料的光催化处理方面具有潜在的应用价值。     

Enhancing the Ability of a Soil Moisture‐based Index for Agricultural Drought Monitoring by Incorporating Root Distribution

Agricultural drought differs from meteorological, hydrological, and socioeconomic drought, being closely related to soil water availability in the root zone, specifically for crop and crop growth stage. In previous studies, several soil moisture indices (e.g., the soil moisture index, soil water deficit index) based on soil water availability have been developed for agricultural drought monitoring. However, when developing these indices, it was generally assumed that soil water availability to crops was equal throughout the root zone, and the effects of root distribution and crop growth stage on soil water uptake were ignored. This article aims to incorporate root distribution into a soil moisture‐based index and to evaluate the performance of the improved soil moisture index for agricultural drought monitoring. The Huang‐Huai‐Hai Plain of China was used as the study area. Overall, soil moisture indices were significantly correlated with the crop moisture index (CMI), and the improved root‐weighted soil moisture index (RSMI) was more closely related to the CMI than averaged soil moisture indices. The RSMI correctly identified most of the observed drought events and performed well in the detection of drought levels. Furthermore, the RSMI had a better performance than averaged soil moisture indices when compared to crop yield. In conclusion, soil moisture indices could improve agricultural drought monitoring by incorporating root distribution.     

湖南长株潭城市群灾害应急管理能力评价

以城市应急管理能力及其内涵为基础,运用层次分析法,对湖南长株潭城市群灾害应急管理能力进行综合评价.结果表明:①从时间上看,长株潭灾害应急管理能力综合评分值由2005年的5.67、3.66、3.34分别增加到2006年的5.82、4.20、3.98,说明长株潭灾害应急管理能力均有所增强,这是因为应急管理能力是随城市社会经济的发展而增强的;②从空间上看,长株潭灾害应急管理能力存在一定的区域差异;③从整体上看,长株潭的灾害应急管理能力排名为长沙市＞株洲市＞湘潭市,其主要是由城市化水平及经济实力的差异所致.     

Photocatalytic purification of volatile organic compounds in indoor air: A literature review

Volatile organic compounds (VOCs) are prevalent components of indoor air pollution. Among the approaches to remove VOCs from indoor air, photocatalytic oxidation (PCO) is regarded as a promising method. This paper is a review of the status of research on PCO purification of VOCs in indoor air. The review and discussion concentrate on the preparation and coating of various photocatalytic catalysts; different kinetic experiments and models; novel methods for measuring kinetic parameters; reaction pathways; intermediates generated by PCO; and an overview of various PCO reactors and their models described in the literature. Some recommendations are made for future work to evaluate the performance of photocatalytic catalysts, to reduce the generation of harmful intermediates and to design new PCO reactors with integrated UV source and reaction surface.     

江苏近岸海域富营养化特征研究

近年来,江苏近岸海域水质不佳,赤潮、绿潮等生态灾害屡屡发生,富营养化是其潜在原因之一。本文对该海域2019年和2020年春、夏、秋季航次监测的无机氮（DIN）、活性磷酸盐（SRP）、叶绿素a(Chl a)等水质参数进行了空间分析,采用指数评价法量化了该海域的富营养化程度,并基于统计分析研究了该海域的富营养化特征。结果表明：江苏近岸海域DIN浓度和SRP浓度总体呈现近岸高、远岸低的分布特征,营养盐浓度与盐度呈显著负相关关系;在降水量和径流量更大的夏季,营养盐浓度和Chl a浓度比春季和秋季更高;丰水年（2020年）相较平水年（2019年）,该海域的氮磷比和富营养化程度均更高。因此,陆源输入对江苏近岸海域的富营养化程度有至关重要的影响,加强对入海河流的监测和排污治理是缓解该海域富营养化的关键。     

海州湾渔港经济区及邻近海域沉积物主要污染物分布特征和潜在风险

本文利用2021年8月海州湾渔港经济区及邻近海域表层沉积物中的主要污染物调查结果,讨论分析了调查海域沉积物中污染物的分布特征及生态风险。结果表明：海州湾渔港经济区沉积物中石油类、有机碳、Cu、Zn、Pb、Cd、Cr、Hg、As的含量都高于渔港邻近海域沉积物;有机碳、石油类、Zn、Cd、Cr、Hg的含量总体上从渔港向邻近海域呈现明显的下降趋势;硫化物的含量总体上从渔港向邻近海域呈现升高趋势;Cu、Pb、As的含量在渔港口门最低,总体上呈现从渔港港口向港内和邻近海域升高的趋势。部分渔港沉积物中石油类含量超过国家一类沉积物质量标准。调查海域重金属综合潜在生态风险总体上较低,但渔港经济区处于中等生态风险水平,其中,Hg和Cd潜在生态风险因子较大。     

西藏盐井地区盐泉同位素特征示踪研究

对西藏盐井地区盐泉、曲孜卡泉、地表水及重要地层进行了同位素测定和分析,结合区域地质构造条件、辅以水化学证据确定泉水的补径排模式。δD~δ18O规律指示出盐泉和温泉的补给类型的差异;用δ18O对泉水的补给区海拔高程进行恢复;泉水、岩样的δ13C~δ18O规律指示出盐泉流经的主要相关层位为上三叠统地层T3b~T3d;其排泄主要受到芒康-盐井复式向斜次级背斜核部的张性裂隙所控制。     

废钻井液对环境污染及固化处理室内研究

目前我国许多油田钻井井场位于稻田、麦田、虾池和鱼塘周围，而废钻井液中含有无机盐、重金属组分、油品及大量有机聚合物，其中有些是有害物质，一口井的废钻井液一般可达200～300m~3。这些废钻井液堆放在井场不进行处理会对周围环境造成较大污染。为此，如何处理这些废钻井液是目前令人极为关心的课题。本文分析了我国一些油田废钻井液的毒性；介绍了毒性提取、评价方法及其对土壤、植物和海洋生物的影响，同时重点介绍用化学固化方法处理废钻井液的结果。通过对现场的5个废钻井液的固化处理室内试验证实，废钻井液固化后有一定强度，其水浸出液清彻透明，达到排放标准，固化体可进行掩埋恢复地貌，也可作为建筑材料使用。     

西藏盐井盐泉地下热卤水水化学特征分析

地下水化学成分受地质、水文地质、岩性等因素的控制，水化学特征研究对水资源的利用、管理及保护具有重要的指导作用。西藏自治区芒康县盐井乡境内，沿澜沧江近岸边长约1．5km范围内出露有50余处矿化度较高、水温为中高温、无色、味咸的天然盐泉。这种地下热卤水的分布特征、水化学特征和化学组分的形成，受地质构造、地下水径流通道、径流速度等条件的影响，因此通过对其水样水化学特征的研究，进一步阐明盐泉形成的基本规律。