天然土壤有机质中菲的分配行为

天然土壤吸附不同初始浓度的菲后,提取胡敏酸组分(包括胡敏酸和富里酸),通过计算得到胡敏素组份所吸附的菲,用以研究菲在2种组份中的动态吸附/分配行为,以及初始浓度的影响,并利用Freundlich式进行拟合.结果表明:天然土壤中菲的吸附/分配过程表现出分阶段特征:从最初的快吸附至48 h左右达到转折点,然后进入慢吸附过程.在快吸附至转折点阶段,胡敏酸组分中菲的吸附比例(吸附量与初始量之比)出现先升后降的波动,可归因于初始时段矿物表面吸附、胡敏素竞争吸附的影响.在慢吸附阶段,胡敏酸中菲的吸附比例变化很小,菲初始浓度的影响也不大;而对于胡敏素组份,低初始浓度条件下菲的吸附比例明显大于高初始浓度条件,并呈现逐步增加的趋势,表明胡敏素组份是慢吸附的主要发生域.模型参数拟合结果显示:胡敏酸、全土、胡敏素吸附的非线性程度依次增加,并随时间逐渐加强.在吸附/分配的动力学过程中,胡敏酸和胡敏素分阶段不同的变化特征反映出土壤有机质组分异质性对非线性吸附行为的影响.     

Supercritical gasification for the treatment of o-cresol wastewater

The supercritical water gasification of phenolic wastewater without oxidant was performed to degrade pollutants and produce hydrogen-enriched gases. The simulated o-cresol wastewater was gasified at 440-650℃ and 27.6 MPa in a continuous Inconel 625 reactor with the residence time of 0.42-1.25 min. The influence of the reaction temperature, residence time, pressure, catalyst, oxidant and the pollutant concentration on the gasification efficiency was investigated. Higher temperature and longer residence time enhanced the o-cresol gasification. The TOC removal rate and hydrogen gasification rate were 90.6% and 194.6%, respectively, at the temperature of 650℃ and the residence time of 0.83 min. The product gas was mainly composed of H2, CO2, CFL and CO, among which the total molar percentage of H2 and CFL was higher than 50%. The gasification efficiency decreased with the pollutant concentration increasing. Both the catalyst and oxidant could accelerate the hydrocarbon gasification at a lower reaction temperature, in which the catalyst promoted H2 production and the oxidant enhanced CO2 generation. The intermediates of liquid effluents were analyzed and phenol was found to be the main composition. The results indicate that the supercritical gasification is a promising way for the treatment of hazardous organic wastewater.     

化学合成聚3-羟基丁酸酯薄膜的生物降解性

利用土壤埋藏,海水降解,活性污泥及高等真菌降解实验对化学法合成的聚３－羟基丁酯,薄膜进行了生物降解性研究。结果表明,降解ＰＨＢ薄膜的微生分布比较广泛;     

日照近岸海域春秋季浮游植物群落结构研究

本文根据2016年5月和11月日照近岸海域的浮游植物调查数据,分析了该海域浮游植物的群落结构特征及其与环境因子的关系。研究海域共发现浮游植物78种,其中,硅藻门（Bacillariophyta）66种,甲藻门（Pyrrophyta）10种,金藻门（Chrysophyta）2种。主要优势种为夜光藻（Noctiluca scintillans）、细弱圆筛藻（Coscinodiscus subtilis）和密连角毛藻（Chaetoceros densus）。春、秋两季平均丰度分别为69.38×104 cells/m3、24.61×104 cells/m3;平均多样性指数为1.56、2.99;平均丰富度指数为2.21、4.00;平均均匀度指数为0.44、0.73。聚类分析表明,研究海域可划分为3个群落。BIOENV分析表明,与研究海域浮游植物群落相关性最密切的环境因子组合为水深、水温、油类、总悬浮物和Zn。Pearson相关分析表明,影响春季浮游植物丰度的环境因子为水深、水温、铵盐、总悬浮物和重金属（Cu、Zn、Hg）;影响秋季浮游植物丰度的环境因子为水深、pH、盐度、DO和铵盐。本研究可为深入研究该海域浮游植物群落结构和影响因子提供重要的基础数据。     

Enhanced performance of alkali-modified Bi2WO6/Bi0.15Ti0.85O2 toward photocatalytic oxidation of HCHO under visible light

Environmental Science and Pollution Research - Photocatalytic oxidation of formaldehyde (HCHO) is considered as one of the promising ways to resolve indoor air HCHO pollution. TiO2 has been well...     

环境监测综合管理平台中应用互联网技术的重点

互联网技术已经出现在了各行各业当中,极大地改变了现代生活的生产实践方式。也可以将互联网技术应用到环境监测综合管理平台当中去,建立起一体化式的管理模式,从数据监测、数据处理、预报预警、呈现展示等多个平台进行高效应用,全面提升环境监测综合管理平台的运行水平,这也是提高环境监测工作质量的重要举措。     

西藏芒康滇金丝猴国家级自然保护区变化监测

以第一次全国地理国情普查与基础性地理国情监测数据为数据源,开展西藏芒康滇金丝猴国家级自然保护区内2015、2016、2017、2018年自然保护区建设与管理情况监测,分别从人工地物、林草资源、露天采掘场等方面进行统计,分析人类活动对自然保护区内的生态系统胁迫以及区内生态恢复情况等。     

Decadal and Episodic Changes in Morphology and Migration of the Confluence Bar of Two Alluvial Rivers in Louisiana,USA

Past research on fluvial dynamics at the confluence of two alluvial rivers has mainly focused on downstream flow structure and bed scoring, often using laboratory experiments and numerical modeling. Little is investigated about yearly and episodic dynamics of confluence mouth bars that can affect downstream morphology using field measurements. In this study, we analyzed the migration of a confluence mouth bar of two free meandering alluvial rivers, the Amite and Comite Rivers in coastal Louisiana, USA from 2002 to 2017. Remote sensing images were utilized to investigate the decade‐long morphologic changes. To assess episodic dynamics, we employed terrestrial laser scanning measurements to acquire high‐accuracy digital elevation models at the confluence before and after three floods in 2017. Our study found that the Amite‐Comite confluence mouth bar migrated downstream 55 m in the past 15 years, and its angle reduced by 55° from 100° to 45°. The fast migration was a result of sediment deposition and channel deformation around the confluence mainly during the years when the tributary‐to‐main channel discharge was lower (<0.25). The study further reveals that a single moderate flood could strongly affect the mouth bar, as shown by an increase of the projected surface area by 114% and an increase of volume of the confluence mouth bar by 68%.