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حرية الوصول المقاله
1 - Williamson-Hall analysis in estimation of lattice strain in nanometer-sized ZnO particles
VD Mote Y Purushotham BN DoleAbstractZnO nanoparticles were prepared by coprecipitation method at 450C. X-ray diffraction result indicates that the sample is having a crystalline wurtzite phase. Transmission electron microscopy (TEM) result reveals that the ZnO sample is spherical in shape with an أکثرAbstractZnO nanoparticles were prepared by coprecipitation method at 450C. X-ray diffraction result indicates that the sample is having a crystalline wurtzite phase. Transmission electron microscopy (TEM) result reveals that the ZnO sample is spherical in shape with an average grain size of about 50nm. X-ray peak broadening analysis was used to evaluate the crystalline sizes and lattice strain by the Williamson-Hall (W-H) analysis. All other relevant physical parameters such as strain, stress, and energy density values were also calculated using W-H analysis with different models, viz, uniform deformation model, uniform deformation stress model and uniform deformation energy density model. The root mean square strain was determined from the interplanar spacing and strain estimated from the three models. The three models yield different strain values; it may be due to the anisotropic nature of the material. The mean particle size of ZnO nanoparticles estimated from TEM analysis, Scherrers formula and W-H analysis is highly intercorrelated. تفاصيل المقالة -
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2 - Synthesis, Characterization, and Crystal Structure Determination of Iron(III) Hetero-ligand Complex Containing Chloride, Dimethyl sulfoxide, pyridine-2, 6-dicarboxylate and Water, [Fe(Pydc)(DMSO)(H2O)Cl]
M. RafizadehA new metal-organic compound, [Fe(Pydc)(DMSO)(H2O)Cl], (where Pydc is pyridine-2, 6-dicarboxylate and DMSO is dimethyl sulfoxide), has been synthesized and characterized by singlecrystal X-ray diffraction, TGA/DTA, IR and Raman spectroscopy. Green-yellow crystals,crysta أکثرA new metal-organic compound, [Fe(Pydc)(DMSO)(H2O)Cl], (where Pydc is pyridine-2, 6-dicarboxylate and DMSO is dimethyl sulfoxide), has been synthesized and characterized by singlecrystal X-ray diffraction, TGA/DTA, IR and Raman spectroscopy. Green-yellow crystals,crystallized in the monoclinic system, space group P21/n, a = 7.2461(4) Å, b = 10.3018(4) Å, c =17.7667(10) Å, α = 90°, β = 90.014°(5), 1329.54(12) Å3, Z = 4 and R = 0.0317. In the molecule ofthe crystallized compound Fe ion is sixfold coordinated with distorted octahedral geometry andthe structure is stabilized by O-H…O hydrogen bonds. تفاصيل المقالة -
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3 - The hydrothermal synthesis and X-ray crystal structure of Ag (1)-4, 4"-bipyridine-based coordination polymer
R. Ranjineh Khojasteh F. Hosseinpouli Mamaghan S. GhelengiHydrothermal synthetic were studied for the preparation of coordination polymeric material basedon Ag (I) and 4, 4"-bipy. A polymeric compound [Ag (4, 4'-bipy)].NO3. (I), was prepared andstructurally characterized by single crystal X-ray diffraction. Compound 1(91% yiel أکثرHydrothermal synthetic were studied for the preparation of coordination polymeric material basedon Ag (I) and 4, 4"-bipy. A polymeric compound [Ag (4, 4'-bipy)].NO3. (I), was prepared andstructurally characterized by single crystal X-ray diffraction. Compound 1(91% yield) was isolatedfrom the reaction of AgNO3 with 4, 41bipy in 2:1 molar ratio. In compound I. each silver (I) islinked to two nitrogens of different but symmetry-equivalent 4, 4"-bipy units in a nearly linearcoordination to form extended chains. تفاصيل المقالة -
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4 - Synthesis, Characterization and Crystal Structure Determination of Copper (II) Complexes with 2,2′-Dimethyl-4,4′-bithiazole
Farank Pirsiavash Vahid Amani Anita AbediCopper(II) complex [Cu(dmbt)2(H2O)](ClO4)2 (1) was prepared from the reaction of copper(II) perchlorate hexahydrate with 2,2'-dimethyl-4,4'-bithiazole (dmbt) ligand in methanol at ambient temperature. The complex was quantitatively and qualitatively characterized by ele أکثرCopper(II) complex [Cu(dmbt)2(H2O)](ClO4)2 (1) was prepared from the reaction of copper(II) perchlorate hexahydrate with 2,2'-dimethyl-4,4'-bithiazole (dmbt) ligand in methanol at ambient temperature. The complex was quantitatively and qualitatively characterized by elemental analysis, absorption and infrared spectrometries. Complex [Cu(DMSO)5](ClO4)2 (2) was also synthesized from the recrystallization of complex [Cu(dmbt)2(H2O)](ClO4)2 (1) in the dimethyl sulfoxide solvent through a slow evaporation of the solvent at room temperature. The compound was characterized by elemental analysis, infrared spectrometry and single-crystal X-ray diffraction. Crystallographic analysis of this complex revealed that the single crystal of this compound is crystallized in the trichlinic crystal structure, with the space group Pī and cell dimensions of a = 10.894(3), b = 10.853(4) and c = 12.947(5)Å as well as the angle β = 111.95 (3)°.Interestingly, this compound is the first example of 5-coordinated copper(II) complex with dimethyl-sulfoxide ligand in a square pyramid structure. تفاصيل المقالة -
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5 - Synthesis, Crystal Structure and Antibacterial Evaluation of Di-μ-chlorido-bis({2-[(4-methoxyphenyl)- iminomethyl]pyridine-κ2N,N']Mercury(II)
Behzad Jamali Aghbash Mahboubeh Manoochehri Maryam Daghighi AsliNew coordination polymer of [HgLCl2]n (1) with HgCl2 and Schiff base bidentate ligand (4-methoxyphenyl) pyridine-2yl methyleneamine (L) was prepared and structurally characterized. In the 1D network structure of 1, the mecury (II) ion adopts an HgN2Cl3 distorted square أکثرNew coordination polymer of [HgLCl2]n (1) with HgCl2 and Schiff base bidentate ligand (4-methoxyphenyl) pyridine-2yl methyleneamine (L) was prepared and structurally characterized. In the 1D network structure of 1, the mecury (II) ion adopts an HgN2Cl3 distorted square pyramid geometry. In this complex, one of the chlorine acts as bridging ligand connecting two adjacent mercury(II) ions while, the L ligand is coordinated to mercury(II)ion in a cyclic-bidentate fashion forming an five-membered metallocyclic ring. Coordination compounds1 has been characterized by infrared spectroscopy, UV-visible spectroscopy, elemental analyses and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P 21/c with a = 9.3053(17), b = 7.1125(13), c = 20.708(4), and β = 80.208(4)°. The antibacterial activities of the complex, ligand and metal salt were tested against Gram-positive bacteria Staphylococcus aureus and Gramnegativebacteria Escherichia coli studied by disk diffusion method. تفاصيل المقالة -
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6 - Cadmium Oxide Thin Films Deposited by a Simplified Spray Pyrolysis Technique for Optoelectronic Applications
K. Usharani A.R. Balu M. Suganya V.S. NagarethinamCadmium oxide thin films were fabricated on glass substrates by a simplified and low cost spray pyrolysis technique at different substrate temperatures. The X-ray diffraction study showed that irrespective of substrate temperature all the films exhibits a preferential أکثرCadmium oxide thin films were fabricated on glass substrates by a simplified and low cost spray pyrolysis technique at different substrate temperatures. The X-ray diffraction study showed that irrespective of substrate temperature all the films exhibits a preferential orientation along the (1 1 1) plane. The values of crystallite size were found to be in the range 20.72 – 29.6 nm. The percentage transmittance and the optical band gap values are found to be in the range of 78 – 89 % and 2.38 – 2.55 eV respectively. The optical transmittance is found to increase gradually with increase in substrate temperature. Urbach energy decreases with increase in substrate temperature. Optical parameters such as refractive index and packing density were calculated. The dispersion parameters of the as-deposited CdO films were calculated to analyze their choice in designing optical devices. PL studies confirm that the films exhibit strong luminescent properties. The value of ρ decreases with increase in substrate temperature and attains a minimum value of 0.26x 10-6 ohm-m for the film coated at 375ºC which has the least thickness. تفاصيل المقالة -
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7 - Synthesis of Nano-Sized Titania Particles by Hydrolysis of Titanium Tetrachloride
M. Farahmandjou M. RamazaniNano-sized titanium dioxide TiO2 powder was successfully prepared from its precursor titanium (IV) chloride by a simple and new wet chemical method. TiCl4 were used as precursor in hydrogen peroxide, H2O2 and ethanol. This solution was then peptized using nitric acid an أکثرNano-sized titanium dioxide TiO2 powder was successfully prepared from its precursor titanium (IV) chloride by a simple and new wet chemical method. TiCl4 were used as precursor in hydrogen peroxide, H2O2 and ethanol. This solution was then peptized using nitric acid and heated under reflux at 80°C. Their physico-chemical properties were then characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-Ray diffraction (XRD). The TEM results showed that the size of as-synthesized TiO2 nanoparticles were in the range of 7-10 nm. The SEM images showed that the size of nanoparticles increased when the nanoparticles prepared in presence of nitric acid. The SEM images showed that the quality of annealed TiO2 nanoaprticles, increased when the nanoparticles synthesized without nitric acid. The crystal structure of the nanoparticles before and after annealing was done by XRD analysis. It was realized that the rutile phase was formed after heat treatment at 600°C. XRD pattern also showed that the size of annealed TiO2 nanoparticles increased from 20 to 50 nm when the nanoparticles prepared with nitric acid. تفاصيل المقالة -
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8 - Low temperature hydrothermal synthesis, evaluation of band gap energies and catalytic performance for Biginelli reactions of Sr2-xAxNb2O7+δ (A=Eu3+ and Nd3+) (x = 0.01 and 0.05) nanomaterials
shahin khademinia mahdi behzadNano powders Eu3+ and Nd3+ - doped Sr2Nb2O7 were prepared by a low temperature hydrothermal method at 120 ºC for 48 h followed by annealing at 400 ᵒC for 3 h among Sr(NO3)2 and Nb2O5, Eu2O3 and Nd2O3 raw materials at stoichiometric 1:1 Sr:Nb molar ratio. Characterizati أکثرNano powders Eu3+ and Nd3+ - doped Sr2Nb2O7 were prepared by a low temperature hydrothermal method at 120 ºC for 48 h followed by annealing at 400 ᵒC for 3 h among Sr(NO3)2 and Nb2O5, Eu2O3 and Nd2O3 raw materials at stoichiometric 1:1 Sr:Nb molar ratio. Characterization of the synthesized materials was performed by X-ray powder diffraction (XRPD) technique. FullProf program employing profile matching with constant scale factors was employed for structural analysis. The results showed that the patterns had a main Sr2Nb2O7 orthorhombic crystal structure with space group Cmc21. FESEM images showed that the synthesized nanomaterials had flower morphologies. Ultraviolet-visible spectra analysis showed that the synthesized Eu3+ and Nd3+ - doped Sr2Nb2O7 nanomaterials had light absorption in the ultraviolet light region. The direct optical band gap energies obtained from UV-Vis absorption spectra were 3.45, 3.50 and 3.80 eV for pure Sr2Nb2O7, S2 and S4, respectively. The catalytic activity of the obtained materials in the one-pot synthesis of the heterocyclic compounds 3,4-dihydropyrimidin-2(1H)-ones (DHPMs) in Biginelli reaction is investigated. The optimized 0.03 g of the catalyst, 95 ºC reaction temperature, and 60 min reaction time are used for the other Biginelli reactions in this work. تفاصيل المقالة -
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9 - Effect of growth time on ZnO thin films prepared by low-temperature chemical bath deposition on PS substrate
Reza Shabannia Nima NaderiZnO thin films were successfully synthesized on a porous silicon (PS) substrate by chemical bath deposition method. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and photoluminescence (PL) analyses were carried out to investigate the eff أکثرZnO thin films were successfully synthesized on a porous silicon (PS) substrate by chemical bath deposition method. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and photoluminescence (PL) analyses were carried out to investigate the effect of growth duration (3, 4, 5, and 6 h) on the optical and structural properties of the aligned ZnO nanorods. The small FWHM and stronger diffraction intensity of growth times of 5 h mean the better crystal quality of ZnO thin films compared to others. The grain size of the ZnO thin films gradually increased with increased the growth time. The FESEM images show that the thickness of ZnO thin films increased with increase of the growth time. Photoluminescence measurements showed that there was a sharp and highly intense UV emission peak when growth time was 5 h. The structural and optical investigations revealed that the ZnO thin films grown on the PS substrate with growth time of 5 h had high structural and optical quality. تفاصيل المقالة -
حرية الوصول المقاله
10 - Low temperature hydrothermal synthesis, evaluation of band gap energies and catalytic performance for Biginelli reactions of Sr2-xAxNb2O7+δ (A=Eu3+ and Nd3+) (x = 0.01 and 0.05) nanomaterials
shahin khademinia Mahdi BehzadNano powders Eu3+ and Nd3+ - doped Sr2Nb2O7 were prepared by a low temperature hydrothermalmethod at 120 ºC for 48 h followed by annealing at 400 ᵒC for 3 h among Sr(NO3)2and Nb2O5, Eu2O3 and Nd2O3 raw materials at stoichiometric 1:1 Sr:Nb molar ratio. Characteriza أکثرNano powders Eu3+ and Nd3+ - doped Sr2Nb2O7 were prepared by a low temperature hydrothermalmethod at 120 ºC for 48 h followed by annealing at 400 ᵒC for 3 h among Sr(NO3)2and Nb2O5, Eu2O3 and Nd2O3 raw materials at stoichiometric 1:1 Sr:Nb molar ratio. Characterizationof the synthesized materials was performed by X-ray powder diffraction (XRPD)technique. FullProf program employing profile matching with constant scale factors was employedfor structural analysis. The results showed that the patterns had a main Sr2Nb2O7 orthorhombiccrystal structure with space group . FESEM images showed that the synthesizednanomaterials had flower morphologies. Ultraviolet-visible spectra analysis showed that thesynthesized Eu3+ and Nd3+ - doped Sr2Nb2O7 nanomaterials had light absorption in the ultravioletlight region. The direct optical band gap energies obtained from UV-Vis absorption spectrawere 3.45, 3.50 and 3.80 eV for pure Sr2Nb2O7, S2 and S4, respectively. The catalytic activity ofthe obtained materials in the one-pot synthesis of the heterocyclic compounds 3,4-dihydropyrimidin-2(1H)-ones (DHPMs) in Biginelli reaction is investigated. The optimized 0.03 g of thecatalyst, 95 ºC reaction temperature, and 60 min reaction time are used for the other Biginellireactions in this work. تفاصيل المقالة -
حرية الوصول المقاله
11 - Effect of growth time on ZnO thin films prepared by low temperature chemical bath deposition on PS substrate
Reza Shabannia Nima NaderiZnO thin films were successfully synthesized on a porous silicon (PS) substrate by chemical bath deposition method. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and photoluminescence (PL) analyses were carried out to investigate the effe أکثرZnO thin films were successfully synthesized on a porous silicon (PS) substrate by chemical bath deposition method. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and photoluminescence (PL) analyses were carried out to investigate the effect of growth duration (3, 4, 5, and 6 h) on the optical and structural properties of the aligned ZnO nanorods. The small FWHM and stronger diffraction intensity of growth times of 5 h mean the better crystal quality of ZnO thin films compared to others. The grain size of the ZnO thin films gradually increased with increased the growth time. The FESEM images show that the thickness of ZnO thin films increased with increase of the growth time. Photoluminescence measurements showed that there was a sharp and highly intense UV emission peak when growth time was 5 h. The structural and optical investigations revealed that the ZnO thin films grown on the PS substrate with growth time of 5 h had high structural and optical quality. تفاصيل المقالة
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