检索结果-南通市图书馆

Aggregation and stability of selenium nanoparticles: Complex roles of surface coating, electrolytes and natural organic matter

引用

Journal of Environmental Sciences 2023年第8期130卷 14-23页

作者： Sujuan Yu Hao Liu Rui Yang Wenjing Zhou Jingfu Liu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department of Environmental Science&EngineeringNorth China Electric Power UniversityBaoding 071000China

The application of selenium nanoparticles(SeNPs)as nanofertilizers may lead to the release of SeNPs into aquatic systems.However,the environmental behavior of SeNPs is rarely studied.In this study,using alginate-coated SeNPs(Alg-SeNPs)and polyvinyl alcohol-coated SeNPs(PVA-SeNPs)as models,we systematically investigated the aggregation and stability of SeNPs under various water conditions.PVA-SeNPs were highly stable in mono-and polyvalent electrolytes,probably due to the strong steric hindrance of the capping agent.Alg-SeNPs only suffered from a limited increase in size,even at 2500 mmol/L NaCl and 200 mmol/L MgCl_(2),while they underwent apparent aggregation in CaCl_(2) and LaCl_(3) solutions.The binding of Ca^(2+) and La^(3+) with the guluronic acid part in alginate induced the formation of cross-linking aggregates.natural organic matter enhanced the stability of Alg-SeNPs in monovalent electrolytes,while accelerated the attachment of Alg-SeNPs in polyvalent electrolytes,due to the cation bridge effects.The long-term stability of SeNPs in natural water showed that the aggregation sizes of Alg-SeNPs and PVA-SeNPs increased to several hundreds of nanometers or above 10μm after 30 days,implying that SeNPs may be suspended in the water column or further settle down,depending on the surrounding water chemistry.The study may contribute to the deep insight into the fate and mobility of SeNPs in the aquatic environment.The varying fate of SeNPs in different natural waters also suggests that the risks of SeNPs to organisms living in diverse depths in the aquatic compartment should be concerned.

关键词： Selenium nanoparticles Aggregation Stability Surface coating Electrolytes natural organic matter

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

natural organic matter quantification in the waters of a semiarid freshwater wetland (Tablas de Daimiel, Spain)

引用

Journal of Environmental Sciences 2013年第1期25卷 114-123页

作者： Montserrat Filella Juan Carlos Rodríguez-Murillo Franc ois Quentel Institute F.-A. Forel University of Geneva10 route de SuisseCH-1290 Versoix Switzerland Museo Nacional de Ciencias naturales CSICSerrano 115 E-28006 MadridSpain Laboratoire de Chimie Analytique UMR-CNRS 6521 Universit de Bretagne Occidentale6 avenue V.Le GorgeuCS 93837F-29238 Brest Cedex 3France

Dissolved organic matter （DOM） concentrations have been measured in the waters of a semiarid freshwater wetland, the Tablas de Daimiel, Spain, when the system-characterised by variable hydroperiodicity conditions, was completely flooded （February 2011）. Fluxes of DOM from the wetland soils to the overlying waters were measured by using a passive diffusion sampler （peeper）. Not only dissolved organic carbon （DOC） concentrations were measured but refractory organic matter （ROM, usually known as humic substances） was also quantified using a novel voltammetric method. Fluorescence spectra were recorded to help in selecting the appropriate standard for ROM quantification, test the homogeneity of DOM in the waters and get an indication of their source. The results obtained show a 7-fold increase in measured ROM concentrations from the Gigtiela River to the outlet, which points to a net exportation of ROM from the wetland and to the existence of an internal source of ROM in the system, probably diffusion from the wetland soils. This hypothesis is confirmed by the flux of ROM from the soils to the water column measured with the peeper and by the common fluorescence characteristics of colunm and interstitial waters. The smaller increase in DOC concentrations along the wetland, in spite of the higher DOC fluxes from soils, suggests that there is significant turnover of organic carbon （OC） in the water column. The system acts as a major carbon sink but, when flooded, exports .OC as DOM.

关键词： organic carbon natural organic matter refractory organic matter DOC ROM humic wetland Daimiel

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of a seasonal diffuse pollution migration on natural organic matter behavior in a stratified dam reservoir

引用

Journal of Environmental Sciences 2010年第6期22卷 908-914页

作者： Soon Ju Yu Jae Yil Lee Sung Ryong Ha National Institute of Environmental Research Department of Urban Engineering Chungbuk National University

This article aims to describe the influence of diffuse pollution on the temporal and spatial characteristics of natural organic matter （NOM） in a stratified dam reservoir, the Daecheong Dam, on the basis of intensive observation results and the dynamic water quality simulation using CE-QUAL-W2. Turbidity is regarded as a comprehensive representation of allochothonous organic matter from diffuse sources in storm season because the turbidity concentration showed reasonable significance in a statistical correlation with the UV absorbance at 254 nm and total phosphorus. CE-QUAL-W2 simulation results showed good consistency with the observed data in terms of dissolved organic matter （DOM） including refractory dissolved organic carbon （RDOC） and labile DOC and also well explained the internal movement of constituents and stratification phenomenon in the reservoir. Instead turbidity and NOM were related well in the upper region of the reservoir according to flow distance, gradually as changing to dissolved form of organic matter, RDOM affected organic matter concentration of reservoir water quality compared to turbidity. To control the increase of soluble organic matters in the dam reservoir, appropriate dam water discharge gate operation provided effective measurement. Because of the gate operation let avoid the accumulation of organic matter within a dam reservoir by shorten of turbid regime retention time.

关键词： CE-QUQL-W2 natural organic matter stratified dam reservoir turbidity flow

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Membrane flux dynamics in the submerged ultrafiltration hybrid treatment process during particle and natural organic matter removal

引用

Journal of Environmental Sciences 2011年第12期23卷 1970-1976页

作者： Wei Zhang Xiaojian Zhang Yonghong Li Jun Wang Chao Chen Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China Beijing Special Engineering Design and Research Institute Beijing 100028 China

Particles and natural organic matter （NOM） are two major concerns in surface water, which greatly influence the membrane filtration process. The objective of this article is to investigate the efiect of particles, NOM and their interaction on the submerged ultrafiltration （UF） membrane flux under conditions of solo UF and coagulation and PAC adsorption as the pretreatment of UF. Particles, NOM and their mixture were spiked in tap water to simulate raw water. Exponential relationship, （JP/JP0 = a×exp{-k[t-（n-1）T]}）, was developed to quantify the normalized membrane flux dynamics during the filtration period and fitted the results well. In this equation, coefficient a was determined by the value of JP/JP0 at the beginning of a filtration cycle, refiecting the flux recovery after backwashing, that is, the irreversible fouling. The coefficient k refiected the trend of flux dynamics. Integrated total permeability （ΣJP） in one filtration period could be used as a quantified indicator for comparison of different hybrid membrane processes or under different scenarios. According to the results, there was an additive effect on membrane flux by NOM and particles during solo UF process. This additive fouling could be alleviated by coagulation pretreatment since particles helped the formation of flocs with coagulant, which further delayed the decrease of membrane flux and benefited flux recovery by backwashing. The addition of PAC also increased membrane flux by adsorbing NOM and improved flux recovery through backwashing.

关键词： ultrafiltration membrane flux particles natural organic matter hybrid process backwashing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Removal of natural organic matter by Forward Osmosis Membrane： Flux Behaviour and Foulant Characterization

引用

Chemical Research in Chinese Universities 2015年第2期31卷 308-314页

作者： XIA Shengji YANG Ruilin ZHANG Xinhuan NI Muzi WAN Yukun YAO Lijuan GAO Naiyun State Key Laboratory of Pollution Control and Resources Reuse Tongji University Shanghai 200092 P. R. China

Fouling of cellulose triacetate（CTA） forward osmosis（FO） membranes by natural organic matter（NOM） was studied by means of a cross-flow fiat-sheet forward osmosis membrane system. The NOM solution was employed as the feed solution（FS）, and a sodium chloride solution（3 tool/L） was used for the draw solution（DS）. The process was conducted at various temperatures and cross-flow velocities. The flux decline was investigated with 3 h forward osmosis operation. The substances absorbed on the membranes were cleaned by ultrasonic oscillation of the fouled membranes and were characterized by methodologies including fluorescence excitation-emission matrices （EEMs） and liquid chromatography with an organic carbon detector（LC-OCD）, and the variations of membrane properties were also investigated by Fourier transform infrared spectrometer（FTIR） and a contact angle meter. It was noted that the rejection efficiency of NOM is remarkable and that ultrasonic oscillation is an effective method to extract the NOM fouled on the CTA membranes after FO process. A higher cross-flow velocity and lower temperature benefit the anti-fouling capacity of the membrane significantly. Although humic substances accounted for the majority of the NOM, aromatic proteins and amino acids were the main fouling components on the membranes, with symbolic FTIR peaks at 2355, 1408 and 873 cm^-1. The present surface foulant made the membranes becoming more hydrophilic, as demonstrated by a significant decrease in contact angle（ranging from 20% to 46%） under all the operation conditions.

关键词： Drinking water Forward osmosis Fouling natural organic matter Extraction Membrane flux

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microbial Changes in the Fluorescence Character of natural organic matter from a Wastewater Source

引用

Journal of Water Resource and Protection 2016年第9期8卷 873-883页

作者： Rémi Riopel Stefan Siemann François Caron Chemistry and Biochemistry Department Laurentian University Sudbury Canada Radiological Protection Research and Instrumentation Branch Canadian Nuclear Laboratories (CNL) Chalk River Canada School of the Environment Laurentian University Sudbury Canada

natural organic matter (NOM) is a mixture of aromatic and aliphatic organic compounds of natural origin in any type of aquatic system. Human activities impact the constituents of NOM, from its production to its fate, particularly in the treatment of domestic waste waters. In this work, the impact of microorganisms isolated from a Waste Water Treatment Plant (WWTP) was investigated to determine the fate of NOM fractions in raw sewage, using fluorescence spectroscopy. Wastewater samples were taken at three different times from a WWTP, and incubated for 4 days under two treatments: 1) “raw sewage”, and 2) “spiked”, i.e., the same raw sewage, spiked with bacteria previously isolated from the WWTP. The incubated waters were analyzed by fluorescence spectroscopy, digitally resolved into NOM components: humic- and fulvic-like, and two types of protein-like, i.e., tryptophan- and tyrosine-like, using a Parallel Factor Analysis routine (PARAFAC). The results demonstrate that the “spiked” samples showed the largest changes with incubation time. The signals of the tryptophan- and tyrosine-like components decreased, suggesting a net microbial digestion of proteinaceous material. In contrast, the fulvic-like signals, and to some extent, the humic-like signals increased, suggesting the production of the associated molecular materials during the incubation period. This study provides direct evidence of human impact on the make-up of NOM: the cultures of microbes found at a WWTP consume the proteinaceous material, whereas humic-like and fulvic-like materials are produced.

关键词： natural organic matter Wastewater Microbial Utilization Fulvic-Like Protein-Like Incubation Fluorescence PARAFAC

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Phosphorus features in FT-IR spectra of natural organic matter

引用

Acta Geochimica 2006年第S1期 259-260页

作者： C. Wayne Honeycutt Tsutomu Ohno James F. Hunt Barbara J. Cade-Menun USDA-ARS New England Plant Soil and Water Laboratory Orono ME 04469 USA Dept. of Plant Soil and Environmental Sciences Univ. of Maine Orono ME 04469 USA Geol. & Environ. Sci. Dept. Stanford University Stanford CA 94305 USA

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Forms and bioavailability of phosphorus associated with natural organic matter

引用

Acta Geochimica 2006年第S1期 259-259页

作者： Tsutomu Ohno Barbara J. Cade-Menun M. Susan Erich C. Wayne Honeycutt Dept. of Plant Soil and Environmental Sciences Univ. of Maine Orono ME 04469 USA Geol. & Environ. Sci. Dept. Stanford University Stanford CA 94305 USA

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Insight into the mechanisms of trichloronitromethane formation by vacuum ultraviolet: QSAR model and FTICR-MS analysis

引用

Journal of Environmental Sciences 2023年第3期125卷 215-222页

作者： Xiaojun Chen Yangtao Wu Weiqiu Zhang Lingjun Bu Shumin Zhu Da Sheng Shiqing Zhou John C.Crittenden Key Laboratory of Building Safety and Energy Efficiency Ministry of EducationDepartment of Water Engineering and ScienceCollege of Civil EngineeringHunan UniversityChangsha 410082China School of Civil and Environmental Engineering and the Brook Byers Institute for Sustainable Systems Georgia Institute of TechnologyGeorgia 30332USA

Vacuum ultraviolet(VUV) photolysis is recognized as an environmental-friendly treatment process. Nitrate(NO-3) and natural organic matter(NOM) are widely present in water source.We investigated trichloronitromethane(TCNM) formation during chlorination after VUV photolysis, because TCNM is an unregulated highly toxic disinfection byproduct. In this study:(1) we found reactive nitrogen species that is generated under VUV photolysis of NO-3react with organic matter to form nitrogen-containing compounds and subsequently form TCNM during chlorination;(2) we found the mere presence of 0.1 mmol/L NO-3can result in the formation of up to 63.96 μg/L TCNM;(3) we found the changes in pH(6.0-8.0), chloride(1-4 mmol/L), and bicarbonate(1-4 mmol/L) cannot effectively diminish TCNM formation;and,(4) we established the quantitative structure-activity relationship(QSAR) model,which indicated a linear relationship between TCNM formation and the Hammett constant(σ) of model compounds;and,(5) we characterized TCNM precursors in water matrix after VUV photolysis and found 1161 much more nitrogen-containing compounds with higher aromaticity were generated. Overall, this study indicates more attention should be paid to reducing the formation risk of TCNM when applying VUV photolysis process at scale.

关键词： Vacuum ultraviolet natural organic matter Hammett constant FTICR-MS Trichloronitromethane

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Comparison of UV-based advanced oxidation processes for the removal of different fractions of NOM from drinking water

引用

Journal of Environmental Sciences 2023年第4期126卷 387-395页

作者： Zhenxing Yao Mingquan Wang Ruibao Jia Qinghua Zhao Li Liu Shaohua Sun Shandong Province City Water Supply and Drainage Water Quality Monitoring Center Jinan 250101China

This study examined the effectiveness for degradation of hydrophobic (HPO),transphilic(TPI) and hydrophilic (HPI) fractions of natural organic matter (NOM) during UV/H_(2)O_(2),UV/TiO_(2)and UV/K2S2O8(UV/PS) advanced oxidation processes (AOPs).The changing characteristics of NOM were evaluated by dissolved organic carbon (DOC),the specific UV absorbance (SUVA),trihalomethanes formation potential (THMFP),organic halogen adsorbable on activated carbon formation potential (AOXFP) and parallel factor analysis of excitation–emission matrices (PARAFAC-EEMs).In the three UV-based AOPs,HPI fraction with low molecular weight and aromaticity was more likely to degradate than HPO and TPI,and the removal efficiency of SUVA for HPO was much higher than TPI and HPI fraction.In terms of the specific THMFP of HPO,TPI and HPI,a reduction was achieved in the UV/H_(2)O_(2)process,and the higest removal rate even reached to 83%.UV/TiO_(2)and UV/PS processes can only decrease the specific THMFP of HPI.The specific AOXFP of HPO,TPI and HPI fractions were all able to be degraded by the three UV-based AOPs,and HPO content is more susceptible to decompose than TPI and HPI content.UV/H_(2)O_(2)was found to be the most effective treatment for the removal of THMFP and AOXFP under given conditions.C1 (microbial or marine derived humic-like substances),C_(2) (terrestrially derived humic-like substances)and C_(3) (tryptophan-like proteins) fluorescent components of HPO fraction were fairly labile across the UV-based AOPs treatment.C_(3) of each fraction of NOM was the most resistant to degrade upon the UV-based AOPs.Results from this study may provide the prediction about the consequence of UV-based AOPs for the degradation of different fractions of NOM with varied characteristics.

关键词： Advanced oxidation processes natural organic matter Trihalomethanes organic halogen adsorbable on activated carbon Parallel factor analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：