• فهرس المقالات Structural properties

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        1 - Borotellurite bio-silica glasses doped by erbium nanoparticles: Structural and thermal properties
        Abdulkarim Muhammad Hamza Umar Sa'ad Aliyu Halimah Mohamed Kamari Ibrahim Gana Geidam Raouf El-Mallawany Nazrin Nazrin Muhammad Nasirudeen Baba
        [(TeO2)0.8 (B2O3)0.2]0.8 (SiO2)0.2}0.99 (Ag2O)0.01]1-y - (Er2O3 NPs)y, and y=0.01,0.02,0.03,0.04 and 0.05 mole% were fabricated by the melt quenching technique. X-ray diffraction (XRD) was used to verify and confirm the glasses’ non-crystallinity. X-ray fluorescen أکثر
        [(TeO2)0.8 (B2O3)0.2]0.8 (SiO2)0.2}0.99 (Ag2O)0.01]1-y - (Er2O3 NPs)y, and y=0.01,0.02,0.03,0.04 and 0.05 mole% were fabricated by the melt quenching technique. X-ray diffraction (XRD) was used to verify and confirm the glasses’ non-crystallinity. X-ray fluorescence (XRF) proved the achievement of silicate of 98.6% quality from rice husk. Fourier transform infrared d (FTIR) results exposed the basic structural units such as TeO4, TeO3, BO4, BO3, Si-O-Si, and O-Si-O within the network. The concentration of Er2O3 nanoparticles’ effects on the thermal properties of ErDBST glasses was duly discussed. From the profiling of the differential scanning calorimetry (DSC), the glass crystallization temperature Tc, and transition temperature Tg are estimated. Also, the thermal stability factor, defined as Ts = Tc - Tg, was higher than 100 oC. From room temperature above the Tg for all the sample glasses, specific heat capacity Cq (≥1.4 J/gK-1) was obtained. The results showed that the glass thermal stability and the transition temperature increase with the addition of Er2O3 nanoparticles (NPs). These suggest that an ErDBST glass exhibit good thermal stability and consequently is a suitable candidate for fiber drawing. تفاصيل المقالة
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        2 - Effect of hydrothermal temperature on the photocatalytic activity of anatase TiO2 nanoparticles
        Malligavathy Rajakumar Pathinettam Padiyan
        We report the significance of hydrothermal temperature of TiO2 nanoparticles on the crystallinity, band gap and the photocatalytic degradation of congo red dye. These nanoparticles are synthesized by hydrothermal method at 120 ˚C, 140 ˚C and 160 ˚C. The anatase phases o أکثر
        We report the significance of hydrothermal temperature of TiO2 nanoparticles on the crystallinity, band gap and the photocatalytic degradation of congo red dye. These nanoparticles are synthesized by hydrothermal method at 120 ˚C, 140 ˚C and 160 ˚C. The anatase phases of the samples are confirmed from the X-ray diffraction pattern and the surface morphology of the sample is visualized in a high-resolution scanning electron microscope. The observed optical band gap value supported that TiO2 nanoparticles can be used as a visible light photocatalytic which is also in agreement with the photoluminescence spectrum. TiO2 nanoparticles prepared at 160 ˚C degrades 98.3 % of congo red in 90 min and the kinetics of degradation is analysed using both pseudo first (Langmuir Hinshelwood model) and second order equations. It is found that the pseudo second order (Blanchard) equation fits well for the whole range of degradation with the correlation coefficient of 0.9999. تفاصيل المقالة
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        3 - Reactivity and aromaticity of hexasiline derivatives Si6XH5 (X = H, F, Cl, Br, COOH, NO2, NH2, CH3 and tBu)
        Mehdi Nabati
        During recent years, the silicon organic-inorganic compounds play the key role in medicinal chemistry and pharmaceutical industry. This is because of their similar chemical properties with carbon compounds. The second reason is related to their easy transfer from the ce أکثر
        During recent years, the silicon organic-inorganic compounds play the key role in medicinal chemistry and pharmaceutical industry. This is because of their similar chemical properties with carbon compounds. The second reason is related to their easy transfer from the cell membranes. So, molecular simulation and study the properties of novel organosilicon compounds can be more important. From this sight of view, we designed and investigated silicon analogs of benzene ring before. Here, the various derivatives of hexasiline molecule will be discussed in the following. Our investigations are based on the density functional theory (DFT) computations. The present research work was focused on investigation of the structural and spectral properties and reactivity of hexasiline using B3LYP/cc-pVDZ level of theory. The Fukui indices (local reactivity) showed that the electrophilic attacks happen on the Si4 atoms of the molecules. On the other hand, the molecules containing electron-donating and electron-withdrawing substituents prefer do nucleophilic reactions on their Si4 and Si3 positions, respectively. تفاصيل المقالة
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        4 - Effect of pH on Structural Properties of Heat-Induced Whey Protein Gels
        F. Farrokhi M.R. Ehsani F. Badii M. Hashemi
        Formation and structure of whey protein heat-induced gels (100 mg mL-1) through heat treatment at 80 °C and pH modifications at three pH values of acidic (2), isoelectric (5.6) and neutral (7) were studied. The obtained results indicated that the nature of the prima أکثر
        Formation and structure of whey protein heat-induced gels (100 mg mL-1) through heat treatment at 80 °C and pH modifications at three pH values of acidic (2), isoelectric (5.6) and neutral (7) were studied. The obtained results indicated that the nature of the primary gel networks was different at each pH value. The heat-induced gels produced at pH of 2 and 7, had acceptable overall shape and consistency which confirmed the significant effect of pH on the regular gel structures. Conversely, the amorphous gel structure was observed at isoelectric pH. According to Atomic Force Microscopy images, the structural unfolding of the protein during denaturation and formation of the fibrillar structures was observed in gel at pH of 2 and stranded aggregates at pH of 7. In terms of textural analysis, in samples at pH of 2 and 7, the required force to fracture gel structure was approximately equal and less than that of the sample at pH of 5.6 which goes back to the amorphous large protein aggregates in gel network at isoelectric pH. The ordered, regular and stable gel structures and high ionic balance were reflected in color parameters and lower amounts of moisture content in the gel matrix of samples at pH of 2 and 7 (P<0.05). The well-organized structure and stable gels network along with their desirable functional characteristics, might reinforce their application as food ingredients in terms of improving the qualitative and textural qualities of food products. This property can facilitate the use of these protein gels in novel food systems. تفاصيل المقالة
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        5 - Effect of Thickness on Structural and Morphological Properties of AlN Films Prepared Using Single Ion Beam Sputtering
        Fatemeh Hajakbari Alireza Hojabri Majid Mojtahedzadeh Larijani
        Aluminum nitride (AlN) thin films have potential applications in microelectronic and optoelectronic devices. In this study, AlN thin films with different thicknesses were deposited on silicon substrate by single ion beam sputtering method. The X-ray diffraction (XRD) sp أکثر
        Aluminum nitride (AlN) thin films have potential applications in microelectronic and optoelectronic devices. In this study, AlN thin films with different thicknesses were deposited on silicon substrate by single ion beam sputtering method. The X-ray diffraction (XRD) spectra revealed that the structure of films with thickness of - nm was amorphous, while the polycrystalline hexagonal AlN with a rough surface was observed at a thickness of nm. Also, the formation of AlN in amorphous films is identified by Fourier transform infrared (FTIR) spectroscopy. Atomic force microscopy (AFM) study confirms that the surface roughness and average grain size of films increased with film thickness. تفاصيل المقالة
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        6 - Thermal Oxidation Times Effect on Structural and Morphological Properties of Molybdenum Oxide Thin Films Grown on Quartz Substrates
        Alireza Hojabri Fatemeh Hajakbari Yalda Ghodrat
        Molybdenumoxide(α-MoO)thin filmswere prepared on quartzand silicon substrates by thermal oxidation of Mo thin films depositedusingDC magnetron sputtering method. Theinfluence of thermal oxidation times ranging from 60-240 min on the structural and morphological pr أکثر
        Molybdenumoxide(α-MoO)thin filmswere prepared on quartzand silicon substrates by thermal oxidation of Mo thin films depositedusingDC magnetron sputtering method. Theinfluence of thermal oxidation times ranging from 60-240 min on the structural and morphological properties ofthe preparedfilms was investigated usingX-ray diffraction,Atomic force microscopy and Fourier transforminfrared spectroscopy. The XRD results revealed that the as depositedfilmwas amorphouswhilethoseformed at thermal oxidationtimes between 60-180 min exhibited polycrystalline orthorhombic molybdenumoxides. Thepresence of (0k0) reflections in XRD patterns indicated the layered structure of α-MoO. Also the surface morphology ofthe films isdependent on the thermal oxidation times. The FTIR spectrum confirmed the formationof MoO3 and the peakat 992.53 cm-1 implythelayered structure of α-MoO3. تفاصيل المقالة
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        7 - The Effect of Heat Treatment on the Microstructural and Superelastic Behavior of NiTi Alloy with 58.5 wt. % Ni
        M. Paryab
        The effect of aging process on hardness as well as the superelastic behavior of NiTi shape memory alloy with 58.5 wt. % Ni has been investigated in this paper. The aging process has been performed at different temperatures ranging from 400 oC to 800oC and for various ex أکثر
        The effect of aging process on hardness as well as the superelastic behavior of NiTi shape memory alloy with 58.5 wt. % Ni has been investigated in this paper. The aging process has been performed at different temperatures ranging from 400 oC to 800oC and for various exposure times from 30 min to 8 hours. The results showed an increase in hardness in the temperature range from 400 oC to 500 oC and then a decrease occurs. At constant temperature with prolonged aging time a gradual increase of hardness occurs. SEM observations showed that there is some precipitation in specimens aged from 600 oC to 800 oC. The decrease of hardness can be due to an increase in precipitate size. The superelastisity investigation at 25 and 60 oC showed that the maximum superelastisit results are related to specimens aged at 400 oC. The superelastisity properties of NiTi were discussed in terms of hardness and microstructure. تفاصيل المقالة
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        8 - Hydroxyapatite Nano-Particles Extracted from Miscellaneous Bestial Resources: Study of Crystal Structure and Microstructure
        Seyed Mehdi Rafiaei Mohammad Khodaei Fateme Eslami
        In this work, hydroxyapatite nano-particles were successfully synthesized via the usage of available fish, hen and bovine bones in waste foods. The crystal structure, microstructure, and functional groups of the synthesized nanostructured bioceramics were studied using أکثر
        In this work, hydroxyapatite nano-particles were successfully synthesized via the usage of available fish, hen and bovine bones in waste foods. The crystal structure, microstructure, and functional groups of the synthesized nanostructured bioceramics were studied using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and fourier transform infrared spectroscopy (FTIR). It was shown that all the used natural resources provide well crystallized crystal structures of hydroxyapatite with a narrow distribution microstructure in the range of 24.4-93.4 nm. As well, it was found that the hydroxyapatite extracted from the fish bone has smaller particle size than those of the hen and bovine. Additionally, all the synthesized productions possess the same functional groups, they can be employed as promising candidates for the bone filler materials in biomedical engineering. تفاصيل المقالة
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        9 - Structural features of La0.55Ca0.45A0.50Co0.50O3 (A = Mg, Mn) nanoparticles over photo-degradation of methyl blue
        Hamid Yousefi Ahmad Gholizadeh Zahra MirbeigSabzevari Azim Malekzadeh
        La0.55Ca0.45A0.5Co0.5O3(A = Mg, Mn) nanoparticles prepared by citrate method were characterized using X-ray diffraction measurement, transmission electron microscopy, Fourier transform infrared and UV-Vis spectroscopy. The structural analysis using X’Pert package and Fu أکثر
        La0.55Ca0.45A0.5Co0.5O3(A = Mg, Mn) nanoparticles prepared by citrate method were characterized using X-ray diffraction measurement, transmission electron microscopy, Fourier transform infrared and UV-Vis spectroscopy. The structural analysis using X’Pert package and Fullprof program is an evidence for the presence of the perovskite structure. The calculated value of crystallite size, particle size and band gap energy of La0.55Ca0.45Mg0.5Co0.5O3 is much less than La0.55Ca0.45Mg0.5Co0.5O3. The photocatalytic activity of the product was studied for degradation of an aqueous solution of methyl blue under solar condition. The effects of three operational parameters including irradiation time, pH, and the catalyst amount on the dye degradation were analyzed using optical absorption spectra. The degradation efficiency of MB solutions in the presence of 10 mg La0.55Ca0.45Mn0.5Co0.5O3 nanoparticles under visible light indicate to be higher than La0.55Ca0.45Mg0.5Co0.5O3 nanoparticles. 96 % degradation is obtained in an aqueous solution at pH = 2.33 and containing 30 mg La0.55Ca0.45Mg0.5Co0.5O3 catalyst after 30 minutes. تفاصيل المقالة
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        10 - Structural Features of La0.55Ca0.45A0.50Co0.50O3 (A=Mg, Mn) Nanoparticles Over Photo-Degradation of Methyl Blue
        Hamid Yousefi Ahmad Gholizadeh Zahra Mirbeig Sabzevari Azim Malekzadeh
        In this paper, La0.55Ca0.45A0.5Co0.5O3(A=Mg, Mn) nanoparticles were synthesized by citratemethod. The samples were characterized using the techniques of using X-ray diffraction(XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and UVVisspec أکثر
        In this paper, La0.55Ca0.45A0.5Co0.5O3(A=Mg, Mn) nanoparticles were synthesized by citratemethod. The samples were characterized using the techniques of using X-ray diffraction(XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and UVVisspectroscopy. The structure was analyzed by Rietveld fitting of the XRD pattern by usingX’Pert package and Fullprof program, these shows that the samples have perovskite structure.The calculated values of crystallite size, particle size and band gap energy of La0.55Ca0.45Mg0.5Co0.5O3 are much less than La0.55Ca0.45Mg0.5Co0.5O3. The effects of three operational parametersincluding irradiation time, pH, and the catalyst amount on the photocatalytic activity ofthe product on the degradation of methyl blue (MB) under solar condition were studied. Thephotocatalytic degradation efficiency of MB solution over La0.55Ca0.45Mn0.5Co0.5O3 nanoparticlesis higher than that over La0.55Ca0.45Mg0.5Co0.5O3 nanoparticles. 96 % degradation is obtainedin an aqueous solution at pH=2.33 and containing 30 mg La0.55Ca0.45Mg0.5Co0.5O3 catalystafter 30 minutes. تفاصيل المقالة