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Full-Text Articles in Physical Sciences and Mathematics
A Simple Biogenic Route To Rapid Synthesis Of Au@Tio2 Nanocomposites By Electrochemically Active Biofilms, Mohammad Mansoob Khan Dr, M. H. Cho
A Simple Biogenic Route To Rapid Synthesis Of Au@Tio2 Nanocomposites By Electrochemically Active Biofilms, Mohammad Mansoob Khan Dr, M. H. Cho
Dr. Mohammad Mansoob Khan
Deposition of gold on titanium dioxide (TiO2) nanoparticles is highly beneficial for maximizing the efficiency of many photocatalytic reactions. In this study, we have reported for the first time the use of an electrochemically active biofilm (EAB) for the synthesis of Au@TiO2 nanocomposite with sodium acetate as the electron donor. The EAB acts as an electron generator for the reduction of gold ions on the surface of TiO2 nanoparticles. It was observed that the TiO2 plays not only as a support for the gold nanoparticles but also as a storage of electrons produced by the EAB within the particles. These …
Synthesis Of Cysteine Capped Silver Nanoparticles By Electrochemically Active Biofilm And Their Antibacterial Activities, Mohammad Mansoob Khan Dr, M. H. Cho Dr
Synthesis Of Cysteine Capped Silver Nanoparticles By Electrochemically Active Biofilm And Their Antibacterial Activities, Mohammad Mansoob Khan Dr, M. H. Cho Dr
Dr. Mohammad Mansoob Khan
Cysteine capped silver nanoparticles (Cys-AgNPs) have been synthesized by employing electrochemically active biofilm (EAB), AgNO3 as precursor and sodium acetate as electron donor in aqueous solution at 30 oC. Cys-AgNPs of 5-10 nm were synthesized and characterized by UV-Vis, FT-IR, XRD and TEM. Capping of the silver nanoparticles with cysteine provides stability to nanoparticles by a thiolate bond between the amino acid and the nanoparticle surface and hydrogen bonding among the Cys-AgNPs. In addition, the antibacterial effects of as-synthesized Cys-AgNPs have been tested against two pathogenic bacteria Escherichia coli (O157:H7) and Pseudomonas aeruginosa (PAO1). The results demonstrate that the as-synthesized …
Enhancement In The Photocatalytic Activity Of Au@Tio2 Nanocomposites By Pretreatment Of Tio2 With Uv Light, Mohammad Mansoob Khan Dr, M. H. Cho Dr
Enhancement In The Photocatalytic Activity Of Au@Tio2 Nanocomposites By Pretreatment Of Tio2 With Uv Light, Mohammad Mansoob Khan Dr, M. H. Cho Dr
Dr. Mohammad Mansoob Khan
A novel, efficient and controlled protocol for the synthesis and enhanced photocatalytic activity of Au@TiO2 nanocomposite is developed. TiO2 (P25) was pretreated by employing UV light (λ = 254 nm) and the pretreated TiO2 was uniformly decorated by gold nanoparticles (AuNPs) in presence of sodium citrate and UV light. UV pretreatment makes the TiO2 activated, as electrons were accumulated within the TiO2 in the conduction band. These accumulated electrons facilitate the formation of AuNPs which were of very small size (2-5 nm), similar morphology and uniformly deposited at TiO2 surface. It leads to formation of stable and crystalline Au@TiO2 nanocomposites. …
Novel Applications Of Nanowires In Different Aspects Of Life. A Short Review, Mohammad Mansoob Khan Dr
Novel Applications Of Nanowires In Different Aspects Of Life. A Short Review, Mohammad Mansoob Khan Dr
Dr. Mohammad Mansoob Khan
Nanowires exhibits novel electronic, thermal, electrochemical, optical and catalytic properties owing to their unique structural one-dimensionality and possible quantum confinement effects in two dimensions. With a broad selection of compositions and band structures, these one-dimensional nanostructures are considered to be the critical components in a wide range of potential nanoscale device applications. The nanowires show a strong broadband optical absorption, which makes them an interesting candidate to serve as an absorber in solar cells. The operation of a solar cell is demonstrated with n-doped nanowires grown on a p-doped silicon wafer. Single or by combing the unique properties shown by …
Ru(Iii), Pd(Ii), Pt(Iii) And Pt(Iv) Complexes Of A Novel 32-Membered Unsymmetrical Macrocyclic Ligand, Mohammad Mansoob Khan Dr
Ru(Iii), Pd(Ii), Pt(Iii) And Pt(Iv) Complexes Of A Novel 32-Membered Unsymmetrical Macrocyclic Ligand, Mohammad Mansoob Khan Dr
Dr. Mohammad Mansoob Khan
Reactions of [N12] macrocyclic ligand, L·2HClO4, with RuCl3, PdCl2, K2[PtCl6], [K2PtCl4] as well as [M(Ph3P)2Cl2] (M = Pd or Pt), and [Ru(Ph3P)3Cl2] produces bimetallic complexes whose analytical data are consistent with the molecular formulae as Ru2LCl4(ClO4)2 (I), Pd2LCl2(ClO4)2 (II), Pt2LCl6(ClO4)2 (III), Pt2LCl2(ClO4)2 (IV) and Ru2LCl2(ClO4)2 (V). Reactions of the ligand with the precursors [M(Ph3P)2Cl2] (M = Pd or Pt), and [Ru(Ph3P)3Cl2], has released all the Ph3P ancillary ligand in solution. Magnetic moment, IR and UV-visible spectroscopic data confirms the encapsulation of metal ions in the macrocyclic cavities through chelation from aza groups of the unsymmetrical imine ( C N ) …
Suitability Assessment Of Water Quality Of Shinta River And Its Impacts On The Users: A Case Study From Gondar, Ethiopia, Mohammad Mansoob Khan Dr, H. R. Sharma Dr
Suitability Assessment Of Water Quality Of Shinta River And Its Impacts On The Users: A Case Study From Gondar, Ethiopia, Mohammad Mansoob Khan Dr, H. R. Sharma Dr
Dr. Mohammad Mansoob Khan
No abstract provided.
Synthesis, Physico-Chemical And Spectroscopic Investigations Of Sodium Dihydrobis(1,2,3-Benzotriazolyl)Borate Ligand And Its Transition Metal Complexes, Mohammad Mansoob Khan Dr, M. M. Rahman, Y. B. Hahn
Synthesis, Physico-Chemical And Spectroscopic Investigations Of Sodium Dihydrobis(1,2,3-Benzotriazolyl)Borate Ligand And Its Transition Metal Complexes, Mohammad Mansoob Khan Dr, M. M. Rahman, Y. B. Hahn
Dr. Mohammad Mansoob Khan
The title ligand, sodium dihydrobis(1,2,3-benzotriazolyl) borate, Na[H2B(BTz)2],was synthesized by refluxing 1 mole of sodium borohydride with 2 moles of 1,2,3- benzotriazole in toluene. The ligand shows ample reactivity towards Cr(III), Mn(II), Fe(III), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) metal ions and forms stable complexes. The ligand and its metal complexes were characterized by physico-hemical and spectroscopic techniques. All the complexes of divalent metal ions are tetrahedral except for Cu(II), which has been proposed to have a square-planar geometry. The complexes of Cr(III) and Fe(III) appear to have an octahedralge ometry. The magnitude of molar conductance of 10−3 M …
Synthesis And Spectral Studies Of A Novel 20-Membered Unsymmetrical Dinucleating [N8] Macrocycle And Its Bimetallic Complexes, M2lcln(Clo4)2 (N = 2, M = Co, Ni Or Cu; N = 4, M = Cr Or Fe), Mohammad Mansoob Khan Dr, Z. A. Siddiqi Dr
Synthesis And Spectral Studies Of A Novel 20-Membered Unsymmetrical Dinucleating [N8] Macrocycle And Its Bimetallic Complexes, M2lcln(Clo4)2 (N = 2, M = Co, Ni Or Cu; N = 4, M = Cr Or Fe), Mohammad Mansoob Khan Dr, Z. A. Siddiqi Dr
Dr. Mohammad Mansoob Khan
A 20-membered octaaza unsymmetrical Schiff base macrocycle, 6,10,16,20-tetramethyl-7,9,17,19-tetraphenyl [1,5,7,9,11,15,17,19]octaazacycloeicosa-5,10,15,20-tetraene dihydroperchlorate, has been obtained as an...
Synthesis And Characterization Of A Novel 32-Membered Unsymmetrical Dinucleating [N12] Macrocycle: Preparation Of Bimetallic Complexes M2lx2(Clo4)2 (M = Zn, Cd Or Hg; X = Cl, Ncs Or No3), Z. A. Siddiqi Dr, Mohammad Mansoob Khan Dr
Synthesis And Characterization Of A Novel 32-Membered Unsymmetrical Dinucleating [N12] Macrocycle: Preparation Of Bimetallic Complexes M2lx2(Clo4)2 (M = Zn, Cd Or Hg; X = Cl, Ncs Or No3), Z. A. Siddiqi Dr, Mohammad Mansoob Khan Dr
Dr. Mohammad Mansoob Khan
The condensation reaction of N-acetylaniline with 1,3-diaminopropane in 2 : 1 mole ratio under reflux condition generates an intermediate species having C55N bonds. The in situ reaction of the intermediate with HCHO and 1,3-diaminopropane in the presence of perchloric acid results in an off-white solid product. Analytical, FAB mass, IR, 1H NMR and electronic spectral data of this solid are consistent with the formation of the dihydroperchlorate salt of an unsymmetrical 32-membered [N12] macrocycle [L.2HClO4] via a capping mechanism of the intermediate species. Reactions of [L 2HClO4] with Group 12 metal salts, MX2, and their precursors, [M(Ph3P)2Cl2], produce bimetallic complexes …
Synthesis And Physico-Chemical Investigations On 16 And 18 Membered [N4] Macrocycles Modified With Appropriate Carbonyl Functions - A Closer Mimic To A Synthetic Cyclic Tetrapeptide; Isolation Of Stable Encapsulated Derivatives With Zn(Ii),Cd(Ii) And Hg(Ii) Ions, Z. A. Siddiqi, V. J. Mathew, Mohammad Mansoob Khan Dr
Synthesis And Physico-Chemical Investigations On 16 And 18 Membered [N4] Macrocycles Modified With Appropriate Carbonyl Functions - A Closer Mimic To A Synthetic Cyclic Tetrapeptide; Isolation Of Stable Encapsulated Derivatives With Zn(Ii),Cd(Ii) And Hg(Ii) Ions, Z. A. Siddiqi, V. J. Mathew, Mohammad Mansoob Khan Dr
Dr. Mohammad Mansoob Khan
Reaction of 1, 2-diamine or 1,3-diamine with succinic/ phthalic anhydride in 1:1 molar ratio at RT in dioxane results in 16-membered or 18 membered macrocycle which posseses tetraamide/ tetrapeptide functions in the molecular unit which however, exhibit ample reactivity towards metallic substrates affording stable compounds with [MLX2 ] (M=Zn,Cd or Hg; X = CI, SCN or CI04 ) stoichiometry as evidenced from the physico-chemical investigations which confirm that the macrocyclic moieties (L| - L6 ) have the appropriate cavity sizes to encapsulate Zn(II), Cd (II) or Hg(II) ions via coordination through nitrogens of the amide/ peptide functions in tetradentate fashion …