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191.
Palaniselvam Kuppusamy Solachuddin J.A.Ichwan Narasimha Reddy Parine Mashitah M.Yusoff Gaanty Pragas Maniam Natanamurugaraj Govindan 《环境科学学报(英文版)》2015,(3):151-157
In this present study, we reported broccoli(Brassica oleracea L.) as a potential candidate for the synthesis of gold and silver nanoparticles(NPs) in green chemistry method. The synthesized metal nanoparticles are evaluated their antimicrobial efficacy against different human pathogenic organisms. The physico-chemical properties of gold nanoparticles were analyzed using different analytical techniques such as a UV–Vis spectrophotometer, Field Emission Scanning Electron Microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction and a Fourier Transform Infrared spectrophotometer. In addition, gold and silver NP antimicrobial efficacy was checked by disc diffusion assay. UV–Vis color intensity of the nanoparticles was shown at 540 and 450 nm for gold and silver nanoparticles respectively. Higher magnification of the Field Emission Scanning Electron Microscopy image shows the variable morphology of the gold nanoparticles such as spherical, rod and triangular shapes and silver nanoparticles were seen in spherical shapes. The average spherical size of the particles was observed in 24–38 nm for gold and 30–45 nm for silver NPs. X-ray diffraction pattern confirmed the presence of gold nanoparticles and silver nanoparticles which were crystalline in nature. Additionally,the functional metabolites were identified by the Fourier Transform Infrared spectroscopy. IR spectra revealed phenols, alcohols, aldehydes(sugar moieties), vitamins and proteins are present in the broccoli extract which are accountable to synthesize the nanoparticles. The synthesized gold and silver NPs inhibited the growth of the tested bacterial and fungal pathogens at the concentration of 50 μg/m L respectively. In addition, broccoli mediated gold and silver nanoparticles have shown potent antimicrobial activity against human pathogens. 相似文献
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城市生活垃圾处理现状及发展趋势 总被引:6,自引:0,他引:6
针对我国目前城市生活垃圾的现状和特点,探讨了城市垃圾产生量随年度变化的规律,垃圾产生量与人口和GDP的关系,分析了我国主要城市的垃圾组分。简要介绍了处理城市生活垃圾的几种方法和处理技术的发展趋势。 相似文献
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中国环境监测总站未来十年发展构想 总被引:1,自引:0,他引:1
阐述了总站未来十年发展的指导思想、目标和原则,明确了总站未来十年发展的重点业务领域,介绍了实现构想的保证措施和重点建设项目。 相似文献
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Dinitropyrenes (DNP) were prepared by nitration of pyrene, and the product was characterized by MS and elemental analysis. Three isomers of DNP were separated by HPLC and identified by 1H-NMR. The eating sequence on the normal phase column is 1, 3-DNP, 1, 6-DNP and 1, 8-DNP, whereas is 1, 6-DNP, 1. 8-DNP and 1. 3-DNP on the reversed phase column. The separation of three DNP isomers under different chromatographic conditions was also discussed. 相似文献