检索结果-南通市图书馆

Occurrence and ecotoxicological risk assessment of pesticides in sediments of the Rosetta branch,Nile River, Egypt

Journal of Environmental Sciences 2022年第8期34卷 21-31页

作者： fawzy eissa Mahmoud Al-Sisi Khaled Ghanem Environment and Bio-agriculture Department Faculty of AgricultureAl-Azhar UniversityNasr CityCairo 11884Egypt Central Laboratory of Residue Analysis of Pesticides and Heavy Metals in Food(QCAP) Agricultural Research CenterDokkiGiza 12311Egypt

This study aimed to(1) monitor the occurrence and spatiotemporal variations of 100 pesticides in sediments collected monthly from July 2018 to June 2019 from sampling sites in El-Rahawy, Sabal, and Tala, along the Rosetta branch of the Nile River, Egypt, and(2) perform an ecological risk assessment for aquatic organisms upon exposure to the detected sediment pesticides based on the risk quotient(RQ) method. Out of the 100 pesticides monitored, 16 pesticides belonging to seven chemical families were detected, and 55% of the sediment samples were contaminated with one or more pesticide residues. The mean concentration(mg/kg dry weight(dw)) and detection frequency(%) of the four most frequently detected pesticides in the sediment samples were as follows: chlorpyrifos(0.18 mg/kg dw and 34%), p,p-DDE(0.018 mg/kg dw and 30%), cypermethrin(0.03 mg/kg dw and 14%), and deltamethrin(0.026 mg/kg dw and 13%). The spatial distribution exhibited that El-Rahawy had the highest pesticide load(2.86 mg/kg dw) among the studied sites, whereas the temporal variations revealed that the highest total pesticide concentrations were detected in winter season(1.73 mg/kg dw). Meanwhile, 12 pesticides showed high RQs(>1), posing a potential ecological risk to aquatic species that live and feed on such sediments.

关键词： Pesticide residues Sediments Spatiotemporal variations Risk quotient

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

Optical Properties of CR-39 Track Etch Detectors Irradiated by Alpha Particles with Different Energies

引用

材料科学与工程（中英文版） 2011年第1期5卷 26-31页

作者： Mostafa fawzy eissa Physics Department Faculty of Science Beni-suef University Beni-Suef 62511 Egypt

Because of the immense variety of applications of CR-39 track detectors, the optical properties of CR-39 polymer track detectors which irradiated by alpha particle at different energies and constant fluence were investigated. The optical properties were studied with ultraviolet-visible (UV-Vis.) spectroscopy. The track properties were verified by using etching technique. Moreover, the optical energy band gap was calculated at different etching times (1.50, 3.00 and 6.00 h). The optical properties studies for the samples and track diameter measurements showed a fair agreement in which a scission occurred in CR-39 polymer chains etched at times 1.50 and 3.00 h when alpha particle irradiation 2.17 MeV. The etching time at 1.50 h was the optimum condition as a method to determine the alpha particle energies by the corresponding optical properties of CR-39.

关键词：径迹探测器光学特性径迹蚀刻粒子辐照能量通量 CR 阿尔法光学性质

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

The Effect of （x-Radiation Dose on CR-39 Polymer Track Detectors Using Positron Annihilation Lifetime and UV-Spectroscopy

引用

材料科学与工程（中英文版） 2010年第11期4卷 48-52页

作者： Mostafa fawzy eissa Esmat Mohamed Hassan Emad A. Badawi Physics Department Faculty of Science Beni-Suef University Beni-Suef 62511 Egypt Physics Department Faculty of Science Aswan South rally University Aswan 81528 Egypt Physics Department Faculty of Science EI-Minia University EI-Minia 61519 Egypt

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

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

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

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：