In the present work, a simple and green co-precipitation method was used to prepare copper oxide-zeolite nanocomposites（CuO-zeolite NCs）. The weight ratio（1, 3, 5, 8 and 10 wt%） of CuO nanoparticles（NPs）loaded i...In the present work, a simple and green co-precipitation method was used to prepare copper oxide-zeolite nanocomposites（CuO-zeolite NCs）. The weight ratio（1, 3, 5, 8 and 10 wt%） of CuO nanoparticles（NPs）loaded into zeolite was investigated to obtain the optimum CuO distribution for antibacterial activities.The prepared CuO-zeolite NCs were characterized by ultraviolet-visible（UV–vis） spectroscopy, Fourier transform infrared（FT-IR） spectroscopy, powder X-ray diffraction（XRD）, and energy dispersive X-ray fluorescence spectrometry（EDXRF）. The transmission electron microscopy（TEM） and field emission scanning electron microscopy（FE-SEM） revealed a uniform surface morphology of the CuO-zeolite NCs.The UV–vis spectrum of NCs showed absorption peaks between 230 and 280 nm for nano-CuO in the XRD patterns, and new peaks appeared between（36.56？–38.83？） related to the CuO. At weight ratio less than 10 wt%, the CuO nanoparticles loaded to the zeolite exhibited spherical shapes with average particle diameter of 6.5 nm measured by TEM and XRD. Antibacterial activities were tested against Gram-negative and Gram-positive bacteria. The obtained results showed that, CuO-zeolite NCs with 8 wt% CuO nanoparticles had the highest antibacterial activities against Bacillus Subtilis B29 and Salmonella Choleraesuis ATCC10708, which can be attributed to the good dispersion of CuO NPs on the zeolite surface.展开更多
The aim of this paper is to report the effect of the addition of cellulose nanocrystals（CNCs） on the mechanical, thermal and barrier properties of poly（vinyl alcohol）/chitosan（PVA/Cs） bio-nanocomposites films pr...The aim of this paper is to report the effect of the addition of cellulose nanocrystals（CNCs） on the mechanical, thermal and barrier properties of poly（vinyl alcohol）/chitosan（PVA/Cs） bio-nanocomposites films prepared through the solvent casting process. The characterizations of PVA/Cs/CNCs films were carried out in terms of X-ray diffraction（XRD）, transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, thermogravimetric analysis（TGA and DTG）, oxygen transmission rate（OTR）, and tensile tests. TEM and SEM results showed that at low loading levels, CNCs were dispersed homogenously in the PVA/Cs matrix. The tensile strength and modulus in films increased from 55.1 MPa to 98.4 MPa and from 395 MPa to 690 MPa respectively, when CNCs content went from 0 wt% to 1.0 wt%. The thermal stability and oxygen barrier properties of PVA/Cs matrix were best enhanced at 1.0 wt% of CNCs loading. The enhanced properties attained by incorporating CNCs can be beneficial in various applications.展开更多
基金support of the Chemistry Department,Faculty of Science,Universiti Putra Malaysia,Selangor,43400,Malaysia
文摘In the present work, a simple and green co-precipitation method was used to prepare copper oxide-zeolite nanocomposites（CuO-zeolite NCs）. The weight ratio（1, 3, 5, 8 and 10 wt%） of CuO nanoparticles（NPs）loaded into zeolite was investigated to obtain the optimum CuO distribution for antibacterial activities.The prepared CuO-zeolite NCs were characterized by ultraviolet-visible（UV–vis） spectroscopy, Fourier transform infrared（FT-IR） spectroscopy, powder X-ray diffraction（XRD）, and energy dispersive X-ray fluorescence spectrometry（EDXRF）. The transmission electron microscopy（TEM） and field emission scanning electron microscopy（FE-SEM） revealed a uniform surface morphology of the CuO-zeolite NCs.The UV–vis spectrum of NCs showed absorption peaks between 230 and 280 nm for nano-CuO in the XRD patterns, and new peaks appeared between（36.56？–38.83？） related to the CuO. At weight ratio less than 10 wt%, the CuO nanoparticles loaded to the zeolite exhibited spherical shapes with average particle diameter of 6.5 nm measured by TEM and XRD. Antibacterial activities were tested against Gram-negative and Gram-positive bacteria. The obtained results showed that, CuO-zeolite NCs with 8 wt% CuO nanoparticles had the highest antibacterial activities against Bacillus Subtilis B29 and Salmonella Choleraesuis ATCC10708, which can be attributed to the good dispersion of CuO NPs on the zeolite surface.
基金financially supported by Universiti Putra Malaysia(research grant RUGS 9199840)
文摘The aim of this paper is to report the effect of the addition of cellulose nanocrystals（CNCs） on the mechanical, thermal and barrier properties of poly（vinyl alcohol）/chitosan（PVA/Cs） bio-nanocomposites films prepared through the solvent casting process. The characterizations of PVA/Cs/CNCs films were carried out in terms of X-ray diffraction（XRD）, transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, thermogravimetric analysis（TGA and DTG）, oxygen transmission rate（OTR）, and tensile tests. TEM and SEM results showed that at low loading levels, CNCs were dispersed homogenously in the PVA/Cs matrix. The tensile strength and modulus in films increased from 55.1 MPa to 98.4 MPa and from 395 MPa to 690 MPa respectively, when CNCs content went from 0 wt% to 1.0 wt%. The thermal stability and oxygen barrier properties of PVA/Cs matrix were best enhanced at 1.0 wt% of CNCs loading. The enhanced properties attained by incorporating CNCs can be beneficial in various applications.
