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Activation cross sections of the deuteron-induced reactions on natural zinc are studied for the production of the medical radionuclide 68Ga. The stacked foil activation method and the γ-ray spectrometry were used. Co-produced radionuclides 65,66,67Ga, 63,65,69mZn, 61Cu, and 58Co are also investigated to evaluate amounts of impurities for practical use of 68Ga. Physical yields of the radionuclides were deduced from the measured cross sections.
Энэхүү судалгааны ажлаар хатуу төлөв дэх урвалын аргаар лантаниум-празеодим гексаборидыг (LaxPr1-xB6, x=0.8 болон 0.6) цельсийн 1150 градус температурт гарган авч рентген дифракц (XRD), электрон микроскоп (SEM) болон соронзон моментыг (VSM) хэмжих багажуудаар шинж чанарыг судалсан ба нягтын функцийн онолд (НФО) тулгуурласан квант химийн тооцоолол гүйцэтгэн соронзон шинж чанарыг судлав.
Энэхүү судалгааны ажлаар хатуу төлөв дэх урвалын аргаар лантаниум-празеодим гексаборидыг (LaxPr1-xB6, x=0.8 болон 0.6) цельсийн 1150 градус температурт гарган авч рентген дифракц (XRD), электрон микроскоп (SEM) болон соронзон моментыг (VSM) хэмжих багажуудаар шинж чанарыг судалсан ба нягтын функцийн онолд (НФО) тулгуурласан квант химийн тооцоолол гүйцэтгэн соронзон шинж чанарыг судлав.
Tin oxide is one of the important materials of the transparent metal oxides, catalysts, and gas sensors. The surface structures of tin oxide has undetermined by experimental methods. Therefore, we studied some low index (110, 101, and 100) surfaces of tin oxide by density functional methods in Quantum espresso program and compared with other theoretical calculation results. The local density and generalized gradient methods were applied with projector augmented, norm-conserving, and ultra-soft pseudo potentials. From the calculation results, the most stable surface was 110 and the most convenient theoretical method was local density functional approximation with projector augmented pseudo potential to compare with other theoretical calculation results.
Abstract: Fabrication of plasmonic mono-disperse nanoparticles on silica substrate such as glass and optical fiber surface is one of important issues for reliable optical nanosensors utilizing plasmonic properties such as surface plasmon resonance (SPR) and surface-enhanced Raman scattering (SERS).
Abstract: Fabrication of plasmonic mono-disperse nanoparticles on silica substrate such as glass and optical fiber surface is one of important issues for reliable optical nanosensors utilizing plasmonic properties such as surface plasmon resonance (SPR) and surface-enhanced Raman scattering (SERS).
Tin oxide is one of the important materials of the transparent metal oxides, catalysts, and gas sensors. The surface structures of tin oxide has undetermined by experimental methods. Therefore, we studied some low index (110, 101, and 100) surfaces of tin oxide by density functional methods in Quantum espresso program and compared with other theoretical calculation results. The local density and generalized gradient methods were applied with projector augmented, norm-conserving, and ultra-soft pseudo potentials. From the calculation results, the most stable surface was 110 and the most convenient theoretical method was local density functional approximation with projector augmented pseudo potential to compare with other theoretical calculation results.
In this work, Zinc oxide (ZnO) nanoparticle was successfully synthesized by sol-gel method. Using the synthesized sample, ZnO thin films were prepared on glass substrate by spin coating. The effects of annealing in temperature range of 250 to 450°C on the structural, morphological and optical properties of the ZnO thin films have been studied. The surface morphology of the ZnO thin films was found to depend slightly on the annealing temperature. The structural properties of the prepared thin films were subjected to analysis by X-ray Diffraction (XRD), its morphological properties were characterized by Scanning Electron Microscopy, the transmittance in the visible region and optical bandgap were determined by Ultraviolet-Visible (UV-Vis) spectrophotometer. Average crystallite size of the synthesized sample was found to be 27 nm by XRD, particle size distribution was determined 27.5 nm by measurement of photon cross-correlation spectrophotometer and bandgap the sample was calculated 3.56 eV from UV-Vis spectrophotometric absorbance.
In this work, Zinc oxide (ZnO) nanoparticle was successfully synthesized by sol-gel method. Using the synthesized sample, ZnO thin films were prepared on glass substrate by spin coating. The effects of annealing in temperature range of 250 to 450°C on the structural, morphological and optical properties of the ZnO thin films have been studied. The surface morphology of the ZnO thin films was found to depend slightly on the annealing temperature. The structural properties of the prepared thin films were subjected to analysis by X-ray Diffraction (XRD), its morphological properties were characterized by Scanning Electron Microscopy, the transmittance in the visible region and optical bandgap were determined by Ultraviolet-Visible (UV-Vis) spectrophotometer. Average crystallite size of the synthesized sample was found to be 27 nm by XRD, particle size distribution was determined 27.5 nm by measurement of photon cross-correlation spectrophotometer and bandgap the sample was calculated 3.56 eV from UV-Vis spectrophotometric absorbance.
Rare-earth hexaborides (REB6) have received newly research on recent years because of these materials have multi-functional properties such as high mechanical, thermal, chemical stability, interesting optical and magnetic properties. Besides, it is possible to tuning and controlling their properties through Rare-earth dopants. In this study, we investigated the magnetic property of La-doped PrB6 using ab-initio based Density functional theory calculation implemented as QUANTUM ESPRESSO package. Results showed that doping Lanthanum into PrB6’s crystal is reason of magnetic phase transition from anti-ferro magnetic (AFM) to Ferro magnetic (FM) phase.
Rare-earth hexaborides (REB6) have received newly research on recent years because of these materials have multi-functional properties such as high mechanical, thermal, chemical stability, interesting optical and magnetic properties. Besides, it is possible to tuning and controlling their properties through Rare-earth dopants. In this study, we investigated the magnetic property of La-doped PrB6 using ab-initio based Density functional theory calculation implemented as QUANTUM ESPRESSO package. Results showed that doping Lanthanum into PrB6’s crystal is reason of magnetic phase transition from anti-ferro magnetic (AFM) to Ferro magnetic (FM) phase.
The isolation of DNA using magnetic nanoparticles has received increased attention due to their facile manipulation and low costs. The initial nanoparticles were obtained by co-precipitation of ferric chloride and ferrous chloride salts followed by surface modification with 3-aminopropyltriethoxysilane (APTES). Further, characterized their physical properties such as crystal structure, morphological appearance, particle size by using X-ray diffraction analysis, scanning electron microscopy (SEM), UV-Vis and photon cross-correlation spectroscopy, respectively. From the results, we synthesized magnetite with 120 nm average particle size. Thereon chemical properties were characterized by IR spectroscopy, SEM with energy dispersion X-ray spectroscopy, water contact angle measurement and nuclear magnetic resonance analysis. Consequently, 1020 cm-1 and 1096 cm-1 wavenumbers from IR spectrum provide us the formation of Si-O-Si bond which indicate APTES had successfully condensed on the magnetic nanoparticles. Afterwards, the isolation of DNA by using home- synthesized magnetic nanoparticles were employed and further subjected to PCR amplification.
The isolation of DNA using magnetic nanoparticles has received increased attention due to their facile manipulation and low costs. The initial nanoparticles were obtained by co-precipitation of ferric chloride and ferrous chloride salts followed by surface modification with 3-aminopropyltriethoxysilane (APTES). Further, characterized their physical properties such as crystal structure, morphological appearance, particle size by using X-ray diffraction analysis, scanning electron microscopy (SEM), UV-Vis and photon cross-correlation spectroscopy, respectively. From the results, we synthesized magnetite with 120 nm average particle size. Thereon chemical properties were characterized by IR spectroscopy, SEM with energy dispersion X-ray spectroscopy, water contact angle measurement and nuclear magnetic resonance analysis. Consequently, 1020 cm-1 and 1096 cm-1 wavenumbers from IR spectrum provide us the formation of Si-O-Si bond which indicate APTES had successfully condensed on the magnetic nanoparticles. Afterwards, the isolation of DNA by using home- synthesized magnetic nanoparticles were employed and further subjected to PCR amplification.
Iron oxide nanoparticles are one of the most studied inorganic nanomaterials are due to their unique optic and magnetic properties. Iron oxide nanoparticles (IONPs) are emerging as promising systems for anti-tumor drug delivery and for nanoparticle mediated thermal therapy of cancer. IONPs are coated with glucose have been successfully synthesized via a simple and facile hydrothermal reduction route. The hydrothermal process involves single precursor iron chloride of iron and glucose as reducing agent and the coating agent. The obtained nanoparticles were characterized by XRD, IR, UV-Vis, and SEM. IONPs particularly magnetite is so far the most commonly used magnetic carriers for a variety of biomedical applications such as MRI contrast enhancement agents, hyperthermia, manipulating cell membranes, biosensors, biolabeling, tracking of cells and drug delivery. Magnetite nanoparticles coated with glucose and gluconic acid have been synthesized via a simple and facile hydrothermal reduction route using a single iron precursor. Glucose acts as a bifunctional agent, it decomposes into reducing species, causing partial reduction of the Fe3+ ions to Fe2+ ions as required for the formation of magnetite and, acts as the source of capping agent to adjust the surface properties and enable the formation of nanoscale particles. In this work, facile and nontoxic glucose a readily available Fe(III) precursor were used to synthesize the coated nanomagnetite without either a purgation or a protection procedure.
Iron oxide nanoparticles are one of the most studied inorganic nanomaterials are due to their unique optic and magnetic properties. Iron oxide nanoparticles (IONPs) are emerging as promising systems for anti-tumor drug delivery and for nanoparticle mediated thermal therapy of cancer. IONPs are coated with glucose have been successfully synthesized via a simple and facile hydrothermal reduction route. The hydrothermal process involves single precursor iron chloride of iron and glucose as reducing agent and the coating agent. The obtained nanoparticles were characterized by XRD, IR, UV-Vis, and SEM. IONPs particularly magnetite is so far the most commonly used magnetic carriers for a variety of biomedical applications such as MRI contrast enhancement agents, hyperthermia, manipulating cell membranes, biosensors, biolabeling, tracking of cells and drug delivery. Magnetite nanoparticles coated with glucose and gluconic acid have been synthesized via a simple and facile hydrothermal reduction route using a single iron precursor. Glucose acts as a bifunctional agent, it decomposes into reducing species, causing partial reduction of the Fe3+ ions to Fe2+ ions as required for the formation of magnetite and, acts as the source of capping agent to adjust the surface properties and enable the formation of nanoscale particles. In this work, facile and nontoxic glucose a readily available Fe(III) precursor were used to synthesize the coated nanomagnetite without either a purgation or a protection procedure.
Bombinin H4 is an antimicrobial peptide that was isolated from the toad Bombina variegata. Bombinin H family peptides are active against gram-positive, gram-negative bacteria, and fungi as well as the parasite Leishmania. Among them, bombinin H4 (H4), which contains d-allo-isoleucine (d-allo-Ile) as the second residue in its sequence, is the most active, and its l-isomer is bombinin H2 (H2). H4 has a significantly lower LC50 than H2 against Leishmania. However, the atomic-level mechanism of the membrane interaction and higher activity of H4 has not been clarified. In this work, we investigated the behavior of the conformations and interactions of H2 and H4 with the Leishmania membrane using 31P solid-state nuclear magnetic resonance (NMR), vibrational circular dichroism (VCD) spectroscopy, and molecular dynamics (MD) simulations. The generation of isotropic 31P NMR signals depending on the peptide concentration indicated the abilities of H2 and H4 to exert antimicrobial activity via membrane disruption. The VCD experiment and density functional theory calculation confirmed the different stability and conformations of the N-termini of H2 and H4. MD simulations revealed that the N-terminus of H4 is more stable than that of H2 in the membrane, in line with the VCD experiment data. VCD and MD analyses demonstrated that the first l-Ile and second d-allo-Ile of H4 tend to take a cis conformation. These residues function as an anchor and facilitate the easy winding of the helical conformation of H4 in the membrane. It may assist to quickly reach to the threshold concentration of H4 on the Leishmania membrane. This article is part of a Special Issue entitled: d-Amino acids: biology in the mirror, edited by Dr. Loredano Pollegioni, Dr. Jean-Pierre Mothet and Dr. Molla Gianluca.
