An economic, eco-friendly and efficient synthesis route for Zinc oxide (ZnO) nanoparticles (NPs) ... more An economic, eco-friendly and efficient synthesis route for Zinc oxide (ZnO) nanoparticles (NPs) using fungus Phanerochaete chrysosporium has been explored along with the single-step impregnation of these nanoparticles on cellulose fibers. The transmission electron microscopy confirmed 50 nm as an average size of ZnO NPs and showed the presence of hexagonal phases. ZnO NPs–cellulose composite was fabricated by amending sugarcane bagasse-extracted cellulose in the reaction mixture during the nanoparticle synthesis. The composite was characterized using Fourier transform infrared, X-ray diffraction patterns, Scanning electron microscopy, and Energy dispersive spectroscopy, thermogravimetric analysis, and also evaluated for its antimicrobial potential. The analyses revealed that well-dispersed hexagonal wurtzite ZnO NPs were present on the surface of the cellulose fibers. ZnO NPs–cellulose demonstrated antibacterial activity against Staphylococcus aureus and Escherichia coli, and antifungal activity against Aspergillus niger, Geotrichum candidum, and Phanerochaete chrysosporium. Thus, the study demonstrated an environmental friendly synthesis of ZnO NPs–cellulose composite using an economic and efficient method, which can be used for developing antimicrobial cellulosic fabric for numerous applications.
This analysis is concerned with the investigation of the capability of alumina coating deposited ... more This analysis is concerned with the investigation of the capability of alumina coating deposited by spray coating method using oxime-modified aluminum(III) isopropoxide as a sol–gel precursor to improve vibration damping and anti-corrosion properties of aluminum alloys. Coating microstructures, thickness and roughness were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM) studies, respectively. To this end, the quality of the coating was determined by the corrosion rate which was analyzed by mean of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The vibration and noise technique were applied to measure comparison of vibration and noise damping of bare and alumina coated samples. The results indicate the alumina coating deposited over aluminum alloy by spray coating method is uniform, homogenous, crack free, having high vibration damping and anti-corrosive behavior.
IOP Conference Series: Earth and Environmental Science, 2021
Environmental and other chemical factors lead to decimated corrosive behaviour of metallic materi... more Environmental and other chemical factors lead to decimated corrosive behaviour of metallic materials that is a severe hazard and an emerging challenge for times. Different protection strategies have been proposed to suppress this problem and among them graphene based coatings are considered to be great technique against corrosive behaviour because of its hydrophobic properties and ability to provide corrosion resistance of composite material. The incorporation of functional nanoparticles can provide the corrosion resistance to mild steel. It regarded a promising nonmaterial in corrosion protection. Present written text focuses on the preventive applications of graphene based nanomaterials, nanocomposites, polymeric coating techniques and their methods to fight the corrosive act of steel.
This work is concerned with the investigation of the capability of alumina coatings, deposited ov... more This work is concerned with the investigation of the capability of alumina coatings, deposited over aluminum alloy by dip coating methods to improve mechanical properties. Alumina coatings were deposited using oxime-modified aluminum (III) isopropoxide as a sol-gel precursor. The Scanning electron microscopy (SEM-EDX) images of the coated samples suggest deposition of uniform and crack free alumina coatings. The mechanical property of the bare, and dip coated aluminum alloy were investigated by the slow strain rate test in 3.5% of NaCl solution. The coated sample indicate higher ultimate tensile strength, it’s reflect the protective behavior of coating.
Heteroleptic complexes of the type [V(NPh)(OiPr)3-n{(ONC)(CH3)(C4H3O-2)}n] {where n = 1 (1), 2 (2... more Heteroleptic complexes of the type [V(NPh)(OiPr)3-n{(ONC)(CH3)(C4H3O-2)}n] {where n = 1 (1), 2 (2) and 3 (3)} were synthesized by the reactions of [V(NPh)(OiPr)3] (A) with 2-acetylfuryl oxime in different molar ratios in anhydrous benzene. All these new derivatives have been characterized by elemental analyses, Fourier transform infrared spectroscopy, nuclear magnetic resonance (1H, 13C {1H}), 51V) and fast atom bombardment mass spectral studies. Spectral studies appear to be indicating mono-dentate and bi-dentate mode of attachment of the oximato moieties in the solution and solid state, respectively. Fast atom bombardment mass study of one of the representative derivative, [V(NPh){(ONC)(CH3)(C4H3O-2)}3] (3) suggests the monomeric nature of all these complexes. Thermogravimetric curve of [V(NPh){(ONC)(CH3)(C4H3O-2)}3] (3) shows large thermal events. Hydrolysis of [V(NPh)(OiPr)3] (A) and [V(NPh){(ONC)(CH3)(C4H3O-2)}3] (3) in moist propan-2-ol medium yielded vanadia, (a) and (b), respectively. However, hydrolysis of [V(NPh)(OiPr)3] (A) in n-hexane medium using calculated amount of water yielded hybrid material, (vn).The presence of (V = NPh) group in (vn) is confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectral studies as well as by the thermogravimetric study. The X-ray diffraction patterns of vanadia, (a) and (b) indicate formation of orthorhombic phase and the scanning electron microscope images of (a) and (b) show rod like morphology of the crystallites. Absorption spectra of vanadia, (a) and (b) indicate energy band gaps of 2.62 and 2.43 eV, respectively.Graphical AbstractHeteroleptic complexes of the type [V(NPh)(OiPr)3-n{(ONC)(CH3)(C4H3O-2)}n] {where n = 1, 2 and 3} were synthesized by the reactions of [V(NPh)(OiPr)3] with 2-acetylfuryl oxime. Hydrolysis of [V(NPh)(OiPr)3] and [V(NPh){(ONC)(CH3)(C4H3O-2)}3] in moist propan-2-ol medium yielded vanadia in orthorhombic phase, whereas, hydrolysis of [V(NPh)(OiPr)3] in n-hexane medium yielded hybrid material containing (V = NPh) linkages.
Reactions of Me2SiCl2 in a 1:2 molar ratio with internally functionalized oximes in the presence ... more Reactions of Me2SiCl2 in a 1:2 molar ratio with internally functionalized oximes in the presence of Et3N in anhydrous benzene afford compounds of the type [Me2Si{ONC(R)Ar}2] {where R=Me, Ar=2-C5H4N (1), 2-C4H3O (2), 2-C4H3S (3); R=H, Ar=2-C5H4N (4), 2-C4H3O (5), 2-C4H3S (6)}. Molecular weight measurements of all these derivatives in freezing benzene and the FAB mass spectral studies of 1 and
ABSTRACT A glycol ether modified precursor, [Nb{O(CH2CH2O)2}(OPri)3] (A) was prepared by the reac... more ABSTRACT A glycol ether modified precursor, [Nb{O(CH2CH2O)2}(OPri)3] (A) was prepared by the reaction of Nb(OPri)5 with O(CH2CH2OH)2 in 1:1 molar ratio in anhydrous benzene. Further reactions of A with a variety of internally functionalized oximes in different molar ratios, yielded heteroleptic complexes of the type, [Nb{O(CH2CH2O)2}(OPri)3−n{ON = C(CH3)(Ar)}n] (1–9) {where Ar = C4H3O-2, n = 1 [1], n = 2 [2], n = 3 [3]; C4H3S-2, n = 1 [4], n = 2 [5], n = 3 [6]; C5H4N-2, n = 1 [7], n = 2 [8], n = 3 [9]}. All the above derivatives have been characterized by elemental analyses, FT-IR, NMR (1H, 13C {1H}) and FAB mass studies. Spectral studies of 1–9 suggest the presence of mono- and bi-dentate mode of oxime moieties, in the solution and in the solid states, respectively. FAB mass studies indicate monomeric nature for 3 and dimeric nature for A. TG curves of A and 6 show their low thermal stability. Soft transformation of A and 3 to pure niobia, a and b, respectively have been carried out by sol–gel technique. The XRD patterns of niobia a and b suggest the formation of nano-size crystallites of average size of 10.8 and 19.5 nm, respectively. The XRD patterns also indicate the formation of monoclinic phase of the niobia in both the cases. Absorption spectra of a and b suggest energy band gaps of 4.95 and 4.39 eV, respectively.
Abstract Six new methyl silicon (IV) precursors of the type [MeSi {ON [DOUBLE BOND] C (R) Ar} 3][... more Abstract Six new methyl silicon (IV) precursors of the type [MeSi {ON [DOUBLE BOND] C (R) Ar} 3][when R= Me, Ar= 2-C 5 H 4 N (1), 2-C 4 H 3 O (2) or 2-C 4 H 3 S (3); and when R= H, Ar= 2-C 5 H 4 N (4), 2-C 4 H 3 O (5) or 2-C 4 H 3 S (6)] were prepared and structurally ...
Reactions of Me2SiCl2 in a 1:2 molar ratio with internally functionalized oximes in the presence ... more Reactions of Me2SiCl2 in a 1:2 molar ratio with internally functionalized oximes in the presence of Et3N in anhydrous benzene afford compounds of the type [Me2Si{ONDimethylsilicon(IV) complexes, [Me2Si{ON
An economic, eco-friendly and efficient synthesis route for Zinc oxide (ZnO) nanoparticles (NPs) ... more An economic, eco-friendly and efficient synthesis route for Zinc oxide (ZnO) nanoparticles (NPs) using fungus Phanerochaete chrysosporium has been explored along with the single-step impregnation of these nanoparticles on cellulose fibers. The transmission electron microscopy confirmed 50 nm as an average size of ZnO NPs and showed the presence of hexagonal phases. ZnO NPs–cellulose composite was fabricated by amending sugarcane bagasse-extracted cellulose in the reaction mixture during the nanoparticle synthesis. The composite was characterized using Fourier transform infrared, X-ray diffraction patterns, Scanning electron microscopy, and Energy dispersive spectroscopy, thermogravimetric analysis, and also evaluated for its antimicrobial potential. The analyses revealed that well-dispersed hexagonal wurtzite ZnO NPs were present on the surface of the cellulose fibers. ZnO NPs–cellulose demonstrated antibacterial activity against Staphylococcus aureus and Escherichia coli, and antifungal activity against Aspergillus niger, Geotrichum candidum, and Phanerochaete chrysosporium. Thus, the study demonstrated an environmental friendly synthesis of ZnO NPs–cellulose composite using an economic and efficient method, which can be used for developing antimicrobial cellulosic fabric for numerous applications.
This analysis is concerned with the investigation of the capability of alumina coating deposited ... more This analysis is concerned with the investigation of the capability of alumina coating deposited by spray coating method using oxime-modified aluminum(III) isopropoxide as a sol–gel precursor to improve vibration damping and anti-corrosion properties of aluminum alloys. Coating microstructures, thickness and roughness were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM) studies, respectively. To this end, the quality of the coating was determined by the corrosion rate which was analyzed by mean of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The vibration and noise technique were applied to measure comparison of vibration and noise damping of bare and alumina coated samples. The results indicate the alumina coating deposited over aluminum alloy by spray coating method is uniform, homogenous, crack free, having high vibration damping and anti-corrosive behavior.
IOP Conference Series: Earth and Environmental Science, 2021
Environmental and other chemical factors lead to decimated corrosive behaviour of metallic materi... more Environmental and other chemical factors lead to decimated corrosive behaviour of metallic materials that is a severe hazard and an emerging challenge for times. Different protection strategies have been proposed to suppress this problem and among them graphene based coatings are considered to be great technique against corrosive behaviour because of its hydrophobic properties and ability to provide corrosion resistance of composite material. The incorporation of functional nanoparticles can provide the corrosion resistance to mild steel. It regarded a promising nonmaterial in corrosion protection. Present written text focuses on the preventive applications of graphene based nanomaterials, nanocomposites, polymeric coating techniques and their methods to fight the corrosive act of steel.
This work is concerned with the investigation of the capability of alumina coatings, deposited ov... more This work is concerned with the investigation of the capability of alumina coatings, deposited over aluminum alloy by dip coating methods to improve mechanical properties. Alumina coatings were deposited using oxime-modified aluminum (III) isopropoxide as a sol-gel precursor. The Scanning electron microscopy (SEM-EDX) images of the coated samples suggest deposition of uniform and crack free alumina coatings. The mechanical property of the bare, and dip coated aluminum alloy were investigated by the slow strain rate test in 3.5% of NaCl solution. The coated sample indicate higher ultimate tensile strength, it’s reflect the protective behavior of coating.
Heteroleptic complexes of the type [V(NPh)(OiPr)3-n{(ONC)(CH3)(C4H3O-2)}n] {where n = 1 (1), 2 (2... more Heteroleptic complexes of the type [V(NPh)(OiPr)3-n{(ONC)(CH3)(C4H3O-2)}n] {where n = 1 (1), 2 (2) and 3 (3)} were synthesized by the reactions of [V(NPh)(OiPr)3] (A) with 2-acetylfuryl oxime in different molar ratios in anhydrous benzene. All these new derivatives have been characterized by elemental analyses, Fourier transform infrared spectroscopy, nuclear magnetic resonance (1H, 13C {1H}), 51V) and fast atom bombardment mass spectral studies. Spectral studies appear to be indicating mono-dentate and bi-dentate mode of attachment of the oximato moieties in the solution and solid state, respectively. Fast atom bombardment mass study of one of the representative derivative, [V(NPh){(ONC)(CH3)(C4H3O-2)}3] (3) suggests the monomeric nature of all these complexes. Thermogravimetric curve of [V(NPh){(ONC)(CH3)(C4H3O-2)}3] (3) shows large thermal events. Hydrolysis of [V(NPh)(OiPr)3] (A) and [V(NPh){(ONC)(CH3)(C4H3O-2)}3] (3) in moist propan-2-ol medium yielded vanadia, (a) and (b), respectively. However, hydrolysis of [V(NPh)(OiPr)3] (A) in n-hexane medium using calculated amount of water yielded hybrid material, (vn).The presence of (V = NPh) group in (vn) is confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectral studies as well as by the thermogravimetric study. The X-ray diffraction patterns of vanadia, (a) and (b) indicate formation of orthorhombic phase and the scanning electron microscope images of (a) and (b) show rod like morphology of the crystallites. Absorption spectra of vanadia, (a) and (b) indicate energy band gaps of 2.62 and 2.43 eV, respectively.Graphical AbstractHeteroleptic complexes of the type [V(NPh)(OiPr)3-n{(ONC)(CH3)(C4H3O-2)}n] {where n = 1, 2 and 3} were synthesized by the reactions of [V(NPh)(OiPr)3] with 2-acetylfuryl oxime. Hydrolysis of [V(NPh)(OiPr)3] and [V(NPh){(ONC)(CH3)(C4H3O-2)}3] in moist propan-2-ol medium yielded vanadia in orthorhombic phase, whereas, hydrolysis of [V(NPh)(OiPr)3] in n-hexane medium yielded hybrid material containing (V = NPh) linkages.
Reactions of Me2SiCl2 in a 1:2 molar ratio with internally functionalized oximes in the presence ... more Reactions of Me2SiCl2 in a 1:2 molar ratio with internally functionalized oximes in the presence of Et3N in anhydrous benzene afford compounds of the type [Me2Si{ONC(R)Ar}2] {where R=Me, Ar=2-C5H4N (1), 2-C4H3O (2), 2-C4H3S (3); R=H, Ar=2-C5H4N (4), 2-C4H3O (5), 2-C4H3S (6)}. Molecular weight measurements of all these derivatives in freezing benzene and the FAB mass spectral studies of 1 and
ABSTRACT A glycol ether modified precursor, [Nb{O(CH2CH2O)2}(OPri)3] (A) was prepared by the reac... more ABSTRACT A glycol ether modified precursor, [Nb{O(CH2CH2O)2}(OPri)3] (A) was prepared by the reaction of Nb(OPri)5 with O(CH2CH2OH)2 in 1:1 molar ratio in anhydrous benzene. Further reactions of A with a variety of internally functionalized oximes in different molar ratios, yielded heteroleptic complexes of the type, [Nb{O(CH2CH2O)2}(OPri)3−n{ON = C(CH3)(Ar)}n] (1–9) {where Ar = C4H3O-2, n = 1 [1], n = 2 [2], n = 3 [3]; C4H3S-2, n = 1 [4], n = 2 [5], n = 3 [6]; C5H4N-2, n = 1 [7], n = 2 [8], n = 3 [9]}. All the above derivatives have been characterized by elemental analyses, FT-IR, NMR (1H, 13C {1H}) and FAB mass studies. Spectral studies of 1–9 suggest the presence of mono- and bi-dentate mode of oxime moieties, in the solution and in the solid states, respectively. FAB mass studies indicate monomeric nature for 3 and dimeric nature for A. TG curves of A and 6 show their low thermal stability. Soft transformation of A and 3 to pure niobia, a and b, respectively have been carried out by sol–gel technique. The XRD patterns of niobia a and b suggest the formation of nano-size crystallites of average size of 10.8 and 19.5 nm, respectively. The XRD patterns also indicate the formation of monoclinic phase of the niobia in both the cases. Absorption spectra of a and b suggest energy band gaps of 4.95 and 4.39 eV, respectively.
Abstract Six new methyl silicon (IV) precursors of the type [MeSi {ON [DOUBLE BOND] C (R) Ar} 3][... more Abstract Six new methyl silicon (IV) precursors of the type [MeSi {ON [DOUBLE BOND] C (R) Ar} 3][when R= Me, Ar= 2-C 5 H 4 N (1), 2-C 4 H 3 O (2) or 2-C 4 H 3 S (3); and when R= H, Ar= 2-C 5 H 4 N (4), 2-C 4 H 3 O (5) or 2-C 4 H 3 S (6)] were prepared and structurally ...
Reactions of Me2SiCl2 in a 1:2 molar ratio with internally functionalized oximes in the presence ... more Reactions of Me2SiCl2 in a 1:2 molar ratio with internally functionalized oximes in the presence of Et3N in anhydrous benzene afford compounds of the type [Me2Si{ONDimethylsilicon(IV) complexes, [Me2Si{ON
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