Jongbin Ahn; Youngkook Kim; Junggoo Lee; Dongsoo Kim
Abstract
Aluminum urea chloride complex was easily synthesized by microwave irradiation from mixed solution and it was used as a precursor for further process. The complexes have proved that urea molecules constructed a coordination sphere around the aluminum atom and formed a stable structure with microwave ...
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Aluminum urea chloride complex was easily synthesized by microwave irradiation from mixed solution and it was used as a precursor for further process. The complexes have proved that urea molecules constructed a coordination sphere around the aluminum atom and formed a stable structure with microwave irradiation. Molar ratio between urea and aluminum chloride was an important factor for the synthesis of AlN particles. After microwave irradiation to the solution with molar ratio (urea/Aluminum chloride) above 6, AlN particles without Al2O3 were formed from aluminum urea chloride by heat treatment at 1000 in nitrogen atmosphere. AlN particles with low oxygen content of 0.85 wt% were successfully synthesized at 1700 under N2 atmosphere in the molar ratio of 6.
I.S. Vijayashree; S. Yallappa; P. Niranjana; J. Manjanna
Abstract
A simple and eco-friendly biosynthesis of silver nanoparticles (AgNPs) is reported here using apple fruit extract as reducing and capping media under microwave irradiation. AgNPs were characterized by UV–visible spectroscopy, XRD, FT-IR and TEM. The kinetics of reduction of aqueous silver ions ...
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A simple and eco-friendly biosynthesis of silver nanoparticles (AgNPs) is reported here using apple fruit extract as reducing and capping media under microwave irradiation. AgNPs were characterized by UV–visible spectroscopy, XRD, FT-IR and TEM. The kinetics of reduction of aqueous silver ions during reaction with the apple fruit extract were monitored with the help of UV-visible spectroscopy. The XRD pattern of AgNPs was found agreeing with the fcc structure of Ag metal. Further, where TEM analysis exhibited formation of spherical shaped nanoparticles in the range of 10–45nm; FTIR analysis was carried out to identify the functional groups which were responsible for reduction/capping of AgNPs and conclude that the characterized AgNPs carry the potential for adoption in various medical and industrial applications.
Faheem Ahmed; Shalendra Kumar; Nishat Arshi; Ram Prakash
Abstract
ZnO nanorods with diameter 90-100 nm range (tip diameter~15 nm) and length of about 2 μm have been prepared using microwave irradiation technique. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results indicate that the nanorods have single phase nature with wurtzite structure ...
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ZnO nanorods with diameter 90-100 nm range (tip diameter~15 nm) and length of about 2 μm have been prepared using microwave irradiation technique. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results indicate that the nanorods have single phase nature with wurtzite structure and preferentially grow along [0001] direction. Raman spectrum shows the mode E2 high at 439 cm −1 that is related to the vibration of oxygen atoms in wurtzite ZnO. Room-temperature ultraviolet-visible (UV-vis) absorption spectrum shows the absorption band at around 399 nm (red-shifted as compared to bulk). This novel nanostructure would be a promising candidate for a variety of future applications.
Ajit Kumar Sharma;Ajay Kumar Mishra
Abstract
In this study, we have synthesized chitosan-grafted-styrene (Ch-g-sty) without any radical initiator or catalyst using microwave (MW) irradiation. Ch-g-sty was synthesized with 187% grafting using 80 % MW power in 40 second at (styrene) 0.13 M, (Chitosan) 0.1 g/25 mL. On the other hand, under similar ...
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In this study, we have synthesized chitosan-grafted-styrene (Ch-g-sty) without any radical initiator or catalyst using microwave (MW) irradiation. Ch-g-sty was synthesized with 187% grafting using 80 % MW power in 40 second at (styrene) 0.13 M, (Chitosan) 0.1 g/25 mL. On the other hand, under similar condition of concentration of styrene and chitosan, 148% grafting was observed with potassium persulphate (K2S2O8)/ascorbic acid as redox initiator and atmospheric oxygen as co-catalyst in 1 h using conventional method at 35 o C. Microwave synthesized Ch-g-sty copolymer was characterized by Fourier transform-Infrared (FTIR) spectroscopy, thermo gravimetric analysis (TGA), X-ray diffraction (XRD) measurement and scanning electron microscopy (SEM). Maximum grafting was optimized by varying the microwave power, exposure time and styrene/chitosan concentration. Ch-g-sty copolymer was found to be more efficient for Cr(VI) removal as compare to conventionally and parent chitosan in aqueous solution. Sorption of Cr(VI) was depending upon pH and concentration, with pH=3 being the optimum value. The equilibrium data followed the Langmuir isotherm model with maximum capacities of 526.3 mg/g, 312.5 mg/g and 166.7 mg/g for Ch-g-sty copolymer, conventional (thermostatic water bath) method and parent chitosan respectively.
Ajit Kumar Sharma;Ajay Kumar Mishra
Abstract
In this study, we have synthesized chitosan-grafted-styrene (Ch-g-sty) without any radical initiator or catalyst using microwave (MW) irradiation. Ch-g-sty was synthesized with 187% grafting using 80 % MW power in 40 second at (styrene) 0.13 M, (Chitosan) 0.1 g/25 mL. On the other hand, under similar ...
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In this study, we have synthesized chitosan-grafted-styrene (Ch-g-sty) without any radical initiator or catalyst using microwave (MW) irradiation. Ch-g-sty was synthesized with 187% grafting using 80 % MW power in 40 second at (styrene) 0.13 M, (Chitosan) 0.1 g/25 mL. On the other hand, under similar condition of concentration of styrene and chitosan, 148% grafting was observed with potassium persulphate (K2S2O8)/ascorbic acid as redox initiator and atmospheric oxygen as co-catalyst in 1 h using conventional method at 35 o C. Microwave synthesized Ch-g-sty copolymer was characterized by Fourier transform-Infrared (FTIR) spectroscopy, thermo gravimetric analysis (TGA), X-ray diffraction (XRD) measurement and scanning electron microscopy (SEM). Maximum grafting was optimized by varying the microwave power, exposure time and styrene/chitosan concentration. Ch-g-sty copolymer was found to be more efficient for Cr(VI) removal as compare to conventionally and parent chitosan in aqueous solution. Sorption of Cr(VI) was depending upon pH and concentration, with pH=3 being the optimum value. The equilibrium data followed the Langmuir isotherm model with maximum capacities of 526.3 mg/g, 312.5 mg/g and 166.7 mg/g for Ch-g-sty copolymer, conventional (thermostatic water bath) method and parent chitosan respectively.
