Novel graphitic carbon nitride(g-C_(3)N_(4))nanosheet/Bi_(5)O_(7)Br/NH_(2)-MIL-88B(Fe)photocatalysts(denoted as GCN-NSh/Bi_(5)O_(7)Br/FeMOF,in which MOF is metal–organic framework)with double S-scheme heterojunctions...Novel graphitic carbon nitride(g-C_(3)N_(4))nanosheet/Bi_(5)O_(7)Br/NH_(2)-MIL-88B(Fe)photocatalysts(denoted as GCN-NSh/Bi_(5)O_(7)Br/FeMOF,in which MOF is metal–organic framework)with double S-scheme heterojunctions were synthesized by a facile solvothermal route.The resultant materials were examined by X-ray photoelectron spectrometer(XPS),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDX),transmission electron microscopy(TEM),high-resolution transmission electron microscopy(HRTEM),photoluminescence spectroscopy(PL),Fourier transform infrared spectroscopy(FT-IR),UV-Vis diffuse reflection spectroscopy(UV-vis DRS),photocurrent density,electrochemical impedance spectroscopy(EIS),and Brunauer–Emmett–Teller(BET)analyses.After the integration of Fe-MOF with GCN-NSh/Bi_(5)O_(7)Br,the removal constant of tetracycline over the optimal GCN-NSh/Bi_(5)O_(7)Br/Fe-MOF(15wt%)nanocomposite was promoted 33 times compared with that of the pristine GCN.The GCN-NSh/Bi_(5)O_(7)Br/Fe-MOF(15wt%)nanocomposite showed superior photoactivity to azithromycin,metronidazole,and cephalexin removal that was 36.4,20.2,and 14.6 times higher than that of pure GCN,respectively.Radical quenching tests showed that·O_(2)-and h+mainly contributed to the elimination reaction.In addition,the nanocomposite maintained excellent activity after 4 successive cycles.Based on the developed n–n heterojunctions among n-GCN-NSh,n-Bi_(5)O_(7)Br,and n-Fe-MOF semiconductors,the double S-scheme charge transfer mechanism was proposed for the destruction of the selected antibiotics.展开更多
Azalomycin F<sub>5a</sub>, a 36-membered macrocyclic lactone isolated from several streptomyces strains, presented remarkable anti-methicillin-resistant Staphylococcus aureus (MRSA) activities. To improve ...Azalomycin F<sub>5a</sub>, a 36-membered macrocyclic lactone isolated from several streptomyces strains, presented remarkable anti-methicillin-resistant Staphylococcus aureus (MRSA) activities. To improve its anti-MRSA potential and to evaluate the probability of MRSA resistant to it before development, the anti-MRSA activities of azalomycin F<sub>5a</sub> in combination with vitamin K<sub>3</sub> were first evaluated using checkerboard assay. Then the minimal concentration inhibiting colony formation by 99% (MIC<sub>99</sub>) and mutant prevention concentration (MPC) of azalomycin F<sub>5a</sub> alone and in combination with vitamin K<sub>3</sub> against MRSA were determined using agar plates with linear antimicrobial concentration decrease. The fractional inhibitory concentration indexes (FICIs) of 0.25 - 0.50 showed the synergistic activity of azalomycin F<sub>5a</sub> in combination with vitamin K<sub>3</sub>. The mutant selection windows (MSWs, MIC<sub>99</sub>-MPC) of azalomycin F<sub>5a</sub> alone against MRSA tested were 2.07 - 6.40 μg/mL, and the MPCs of azalomycin F<sub>5a</sub> in combination with vitamin K<sub>3</sub> against MRSA tested were 1.60 - 3.20 μg/mL. These indicated that the MPCs of azalomycin F<sub>5a</sub> in combination could drop down to below its MIC<sub>99</sub> alone. According to the hypothesis of MSW, the narrower MSWs of azalomycin F<sub>5a </sub>alone, even closed MSWs in combination with vitamin K<sub>3</sub>, together with their synergistic anti-MRSA activities, indicated that azalomycin F<sub>5a </sub>had a good potential to develop as a new antimicrobial agent.展开更多
Devising exceptional S-scheme heterojunction photocatalysts utilized in annihilating pharmaceuticals and chromium contamination is significant for addressing the problem of global water pollution.In this work,a chemic...Devising exceptional S-scheme heterojunction photocatalysts utilized in annihilating pharmaceuticals and chromium contamination is significant for addressing the problem of global water pollution.In this work,a chemically bonded Mn0.5Cd_(0.5)S/BiOBr S-scheme heterostructure with oxygen vacancies is ingeniously developed through a facile in-situ solvothermal synthesis.The designed Mn0.5Cd_(0.5)S/BiOBr heterojunction exhibits eminently reinforced photo-activity for destruction of tetracycline hydrochloride and Cr(VI)as compared with its individual components.This substantial photo-redox performance amelioration is benefitted from the creation of an intense internal electric field(IEF)via supplying powerful driving force and migration highway by interfacial chemical bond to foster the S-scheme electron/hole disintegration.More intriguingly,the IEF at the hetero-interface drives the fast consumption of the photo-induced holes in Mn0.5Cd_(0.5)S by the photoelectrons from BiOBr,profoundly boosting the enrichment of active photo-carriers and sparing the photo-corrosion of Mn0.5Cd_(0.5)S.Furthermore,Mn0.5Cd_(0.5)S/BiOBr with exceptional anti-interference property can work efficiently in real water matrices.Multiple uses of the recycled Mn0⋅5Cd0⋅5S/BiOBr evidence its prominent robustness and stability.This achievement indicates the vast potential of chemically bonded S-scheme photosystems with structural defects in the design of photo-responsive materials for effective wastewater treatment.展开更多
INTRODUCTIONThe 1990’s have brought a significant promise and the hopefor a better and brighter future in the new millennium forpatients with inflammatory bowel disease(IBD).A betterunderstanding of the pathophysiolo...INTRODUCTIONThe 1990’s have brought a significant promise and the hopefor a better and brighter future in the new millennium forpatients with inflammatory bowel disease(IBD).A betterunderstanding of the pathophysiology of IBD symptoms hasled to newer treatment modalities and streamlining oftherapy for specific subsets of patients.展开更多
文摘Novel graphitic carbon nitride(g-C_(3)N_(4))nanosheet/Bi_(5)O_(7)Br/NH_(2)-MIL-88B(Fe)photocatalysts(denoted as GCN-NSh/Bi_(5)O_(7)Br/FeMOF,in which MOF is metal–organic framework)with double S-scheme heterojunctions were synthesized by a facile solvothermal route.The resultant materials were examined by X-ray photoelectron spectrometer(XPS),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDX),transmission electron microscopy(TEM),high-resolution transmission electron microscopy(HRTEM),photoluminescence spectroscopy(PL),Fourier transform infrared spectroscopy(FT-IR),UV-Vis diffuse reflection spectroscopy(UV-vis DRS),photocurrent density,electrochemical impedance spectroscopy(EIS),and Brunauer–Emmett–Teller(BET)analyses.After the integration of Fe-MOF with GCN-NSh/Bi_(5)O_(7)Br,the removal constant of tetracycline over the optimal GCN-NSh/Bi_(5)O_(7)Br/Fe-MOF(15wt%)nanocomposite was promoted 33 times compared with that of the pristine GCN.The GCN-NSh/Bi_(5)O_(7)Br/Fe-MOF(15wt%)nanocomposite showed superior photoactivity to azithromycin,metronidazole,and cephalexin removal that was 36.4,20.2,and 14.6 times higher than that of pure GCN,respectively.Radical quenching tests showed that·O_(2)-and h+mainly contributed to the elimination reaction.In addition,the nanocomposite maintained excellent activity after 4 successive cycles.Based on the developed n–n heterojunctions among n-GCN-NSh,n-Bi_(5)O_(7)Br,and n-Fe-MOF semiconductors,the double S-scheme charge transfer mechanism was proposed for the destruction of the selected antibiotics.
文摘Azalomycin F<sub>5a</sub>, a 36-membered macrocyclic lactone isolated from several streptomyces strains, presented remarkable anti-methicillin-resistant Staphylococcus aureus (MRSA) activities. To improve its anti-MRSA potential and to evaluate the probability of MRSA resistant to it before development, the anti-MRSA activities of azalomycin F<sub>5a</sub> in combination with vitamin K<sub>3</sub> were first evaluated using checkerboard assay. Then the minimal concentration inhibiting colony formation by 99% (MIC<sub>99</sub>) and mutant prevention concentration (MPC) of azalomycin F<sub>5a</sub> alone and in combination with vitamin K<sub>3</sub> against MRSA were determined using agar plates with linear antimicrobial concentration decrease. The fractional inhibitory concentration indexes (FICIs) of 0.25 - 0.50 showed the synergistic activity of azalomycin F<sub>5a</sub> in combination with vitamin K<sub>3</sub>. The mutant selection windows (MSWs, MIC<sub>99</sub>-MPC) of azalomycin F<sub>5a</sub> alone against MRSA tested were 2.07 - 6.40 μg/mL, and the MPCs of azalomycin F<sub>5a</sub> in combination with vitamin K<sub>3</sub> against MRSA tested were 1.60 - 3.20 μg/mL. These indicated that the MPCs of azalomycin F<sub>5a</sub> in combination could drop down to below its MIC<sub>99</sub> alone. According to the hypothesis of MSW, the narrower MSWs of azalomycin F<sub>5a </sub>alone, even closed MSWs in combination with vitamin K<sub>3</sub>, together with their synergistic anti-MRSA activities, indicated that azalomycin F<sub>5a </sub>had a good potential to develop as a new antimicrobial agent.
基金supported by the National Natural Science Foundation of China(U1809214)the Natural Science Foundation of Zhejiang Province(LY20E080014 and LTGN23E080001)the Science and Technology Project of Zhoushan(2022C41011).
文摘Devising exceptional S-scheme heterojunction photocatalysts utilized in annihilating pharmaceuticals and chromium contamination is significant for addressing the problem of global water pollution.In this work,a chemically bonded Mn0.5Cd_(0.5)S/BiOBr S-scheme heterostructure with oxygen vacancies is ingeniously developed through a facile in-situ solvothermal synthesis.The designed Mn0.5Cd_(0.5)S/BiOBr heterojunction exhibits eminently reinforced photo-activity for destruction of tetracycline hydrochloride and Cr(VI)as compared with its individual components.This substantial photo-redox performance amelioration is benefitted from the creation of an intense internal electric field(IEF)via supplying powerful driving force and migration highway by interfacial chemical bond to foster the S-scheme electron/hole disintegration.More intriguingly,the IEF at the hetero-interface drives the fast consumption of the photo-induced holes in Mn0.5Cd_(0.5)S by the photoelectrons from BiOBr,profoundly boosting the enrichment of active photo-carriers and sparing the photo-corrosion of Mn0.5Cd_(0.5)S.Furthermore,Mn0.5Cd_(0.5)S/BiOBr with exceptional anti-interference property can work efficiently in real water matrices.Multiple uses of the recycled Mn0⋅5Cd0⋅5S/BiOBr evidence its prominent robustness and stability.This achievement indicates the vast potential of chemically bonded S-scheme photosystems with structural defects in the design of photo-responsive materials for effective wastewater treatment.
文摘INTRODUCTIONThe 1990’s have brought a significant promise and the hopefor a better and brighter future in the new millennium forpatients with inflammatory bowel disease(IBD).A betterunderstanding of the pathophysiology of IBD symptoms hasled to newer treatment modalities and streamlining oftherapy for specific subsets of patients.
