Methotrexate(MTX)is one of the most consumed anti-cancer drugs in the pharmaceutical market around the world.The widespread occurrence of MTX in aquatic environment through hospital effluent has attracted increasing c...Methotrexate(MTX)is one of the most consumed anti-cancer drugs in the pharmaceutical market around the world.The widespread occurrence of MTX in aquatic environment through hospital effluent has attracted increasing concern due to its potential to induce water pollution.In the present study,the degradation of MTX in aqueous medium was investigated by UV-activated peroxymonosulfate(PMS).A significant improvement in degradation rate by increasing UV intensity and PMS concentration while the decrease in degradation efficiency with the increase of solution p H and initial concentration of MTX was observed.The proposed UV/PMS process could achieve more than 90%MTX degradation in 30 min with a good mineralization degree(65%).A pseudofirst order kinetic model was employed and successfully predicted the degradation of MTX.The effect of other operational parameters such as the initial concentration of the targeted compound,dosage of oxidant(PMS),solution p H and UV intensity on the degradation rate were investigated.At the last,the main transform intermediates were identified using LC–MS and possible degradation pathways were proposed.The results show that UV/PMS can be used as an efficient technology to treat pharmaceuticals such as methotrexate containing water and wastewater.展开更多
电光相位调制器(Phase Modulator,PM)因无需偏置,线性调制和插损小等优点,被广泛应用于相干光通信、微波信号产生、处理和测量等领域.调制指数和半波电压是评估PM性能的关键参数.传统基于(Optical Spectrum Analyzer,OSA)的方法面临测...电光相位调制器(Phase Modulator,PM)因无需偏置,线性调制和插损小等优点,被广泛应用于相干光通信、微波信号产生、处理和测量等领域.调制指数和半波电压是评估PM性能的关键参数.传统基于(Optical Spectrum Analyzer,OSA)的方法面临测量分辨率低和存在测量盲区问题.为此,本文提出了一种基于电谱分析(Unequal Voltage based on Electrical Spectrum Analyzer,UV-ESA)的自校准、高精度的PM特性参数测量方法.该方法利用同频、不同驱动电压比的情况下,通过分析失谐光学载波和调制边带分别与载波拍音电谱,实现PM调制指数和半波电压的高频特性参数测量.该方法不需改变测量链路结构,无需辅助宽带微波源或电光调制器,验证了所提方法的有效性,并对比OSA方法对结果的准确性进行了验证.展开更多
β-lactam antibiotics in aquatic environment have severely damaged ecological stability and caused a series of environmental pollution problems to be solved urgently.Herein,a novel composite photocatalyst prepared by ...β-lactam antibiotics in aquatic environment have severely damaged ecological stability and caused a series of environmental pollution problems to be solved urgently.Herein,a novel composite photocatalyst prepared by loading carbon dots(CDs)onto rod-like CoFe_(2)O_(4)(CFO),which can effectively degrade amoxicillin(AMX)by photocata lytic/peroxy mono sulfate(PMS)activation under visible light irradiation.The degradation results exhibits that the optimal degradation efficiency with 97.5%within 80 min is achievd by the CDs-CFO-5 composite.Such enhanced activity is ascribed to the introduction of CDs that effectively improves the separation efficiency of photogenerated electron pairs and creates new active sites as electron bridges that improve the photocata lytic performance.More importantly,a strong synergistic between CDs and photo-induced electrons generated from CFO can further activiate PMS to provide more SO4-·and·OH radicals for boosting the degradation ability towards AMX.The present study aims to elucidate positive role of CDs in photocata lytic/peroxy monosulfate activation during the degradation reaction.展开更多
基金Supported by the 863 High Technical Scheme(2009AA06Z310)the Fund for Creative Research Groups of China(51121062)+4 种基金the National Natural Science Foundation of China(5082100251108117)SKLUWRE(2010DX10)the Special S&T Projecton Water Treatment and Control of Pollution(2009ZX07424-0052009 ZX07424-006)
基金the financial support of research grants from the Hong Kong Polytechnic University(Q67H)and Higher Education Commission(HEC),Pakistan for the financial support during IRSIP。
文摘Methotrexate(MTX)is one of the most consumed anti-cancer drugs in the pharmaceutical market around the world.The widespread occurrence of MTX in aquatic environment through hospital effluent has attracted increasing concern due to its potential to induce water pollution.In the present study,the degradation of MTX in aqueous medium was investigated by UV-activated peroxymonosulfate(PMS).A significant improvement in degradation rate by increasing UV intensity and PMS concentration while the decrease in degradation efficiency with the increase of solution p H and initial concentration of MTX was observed.The proposed UV/PMS process could achieve more than 90%MTX degradation in 30 min with a good mineralization degree(65%).A pseudofirst order kinetic model was employed and successfully predicted the degradation of MTX.The effect of other operational parameters such as the initial concentration of the targeted compound,dosage of oxidant(PMS),solution p H and UV intensity on the degradation rate were investigated.At the last,the main transform intermediates were identified using LC–MS and possible degradation pathways were proposed.The results show that UV/PMS can be used as an efficient technology to treat pharmaceuticals such as methotrexate containing water and wastewater.
文摘电光相位调制器(Phase Modulator,PM)因无需偏置,线性调制和插损小等优点,被广泛应用于相干光通信、微波信号产生、处理和测量等领域.调制指数和半波电压是评估PM性能的关键参数.传统基于(Optical Spectrum Analyzer,OSA)的方法面临测量分辨率低和存在测量盲区问题.为此,本文提出了一种基于电谱分析(Unequal Voltage based on Electrical Spectrum Analyzer,UV-ESA)的自校准、高精度的PM特性参数测量方法.该方法利用同频、不同驱动电压比的情况下,通过分析失谐光学载波和调制边带分别与载波拍音电谱,实现PM调制指数和半波电压的高频特性参数测量.该方法不需改变测量链路结构,无需辅助宽带微波源或电光调制器,验证了所提方法的有效性,并对比OSA方法对结果的准确性进行了验证.
基金founding support from the National Natural Science Foundation of China(Nos.21906072,22006057 and 31971616)the Natural Science Foundation of Jiangsu Province(BK20190982)+4 种基金“Doctor of Mass Entrepreneurship and Innovation”Project in Jiangsu Province,Henan Postdoctoral Foundation(202003013)Doctoral Scientific Research Foundation of Jiangsu University of Science and Technology(China)(1062931806 and 1142931803)the Science and Technology Research Project of the Department of Education of Jilin Province(JJKH20200039KJ)the Science and Technology Research Project of Jilin City(20190104120,201830811)the Project of Jilin Provincial Science and Technology Development Plan(20190201277JC,20200301046RQ,YDZJ202101ZYTS070)。
文摘β-lactam antibiotics in aquatic environment have severely damaged ecological stability and caused a series of environmental pollution problems to be solved urgently.Herein,a novel composite photocatalyst prepared by loading carbon dots(CDs)onto rod-like CoFe_(2)O_(4)(CFO),which can effectively degrade amoxicillin(AMX)by photocata lytic/peroxy mono sulfate(PMS)activation under visible light irradiation.The degradation results exhibits that the optimal degradation efficiency with 97.5%within 80 min is achievd by the CDs-CFO-5 composite.Such enhanced activity is ascribed to the introduction of CDs that effectively improves the separation efficiency of photogenerated electron pairs and creates new active sites as electron bridges that improve the photocata lytic performance.More importantly,a strong synergistic between CDs and photo-induced electrons generated from CFO can further activiate PMS to provide more SO4-·and·OH radicals for boosting the degradation ability towards AMX.The present study aims to elucidate positive role of CDs in photocata lytic/peroxy monosulfate activation during the degradation reaction.
