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Objective(s): Breast cancer is a fatal disease and the leading cause of mortality in women. Radiofrequency hyperthermia is an approach to the treatment of cancer cells through increasing their temperature. The present study aimed to investigate breast tumor ablation via radiofrequency hyperthermia in the presence and non-presence states of magnetite nanoparticles and assess the effects of magnetite nanoparticles on breast cancer treatment in hyperthermia. Materials and Methods: Radius hemisphere geometry (5 cm) was designed, which was similar to an actual breast based on the fat tissues, glandular tissues as a semi-oval embedded in the hemisphere, and a radius sphere (1 cm) as a tumor region inside. After utilization in a three-dimensional printer, each layer of the phantom was filled with a proper combination of oil-gelatin with similar dielectric and thermal properties to an actual breast. To evaluate the effects of the magnetite nanoparticles, three weights of the magnetite were added to the tumor region (0.01, 0.05, and 0.1 g). Finally, the phantom was placed in a radiofrequency device with the frequency of 13.56 MHz. Results: Temperature differences were measured at four different points of the phantom. The power and time in the treatment were estimated at 40 watts and five minutes, respectively. The temperature and specific absorption rate plots were obtained for all the states in several graphs for five minutes. The results showed that the heat generation with the utilization of the magnetite state was higher by approximately 2.5-7°C compared to the state without magnetite. Furthermore, the temperature of 0.05 gram of magnetite indicated that without causing damage in the healthy tissues, the entire tumor region could attain adequate heat uniformly (6.1-6.4°C). Conclusion: Therefore, it could be concluded that 0.05 gram of magnetite could cause ablation in the entire tumor region. [ABSTRACT FROM AUTHOR]

ZnO nanostructures were synthesized through arc discharge of zinc electrodes in deionized (DI) water. X-ray diffraction (XRD) analysis of the prepared nanostructures indicates formation of crystalline ZnO of hexagonal lattice structures. Transmission electron microscopy (TEM) images illustrate rod-like as well as semi spherical ZnO nanoparticles with 15–20 nm diameter range, which were formed during the discharge process with 5 A arc current. The average particle size was found to increase with the increasing arc current. X-ray photoelectron spectroscopy (XPS) analysis confirms formation of ZnO at the surface of the nanoparticles. Surface area of the sample prepared at 5 A arc current, measured by BET analysis, was 34 m/g. Photodegradation of Rhodamine B (Rh. B) shows that the prepared samples at lower currents have a higher photocatalytic activity due to larger surface area and smaller particle size. [ABSTRACT FROM AUTHOR]

We report a simple, inexpensive and one-step synthesis route of colloidal gold nanoparticles using arc discharge between titanium electrodes in HAuCl4 solution achieving long-time stability. Gold nanoparticles of 8 nm diameter were formed during reduction of HAuCl4 in the plasma discharge zone. The resulting nanoparticles were characterized using UV–Vis spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Optical absorption spectroscopy of as prepared samples at 15 A arc current in HAuCl4 solution shows a surface plasmon resonance around 550 nm. It was found that sodium citrate acts as a stabilizer and surface capping agent of the colloidal nanoparticles. SEM images exhibit the increase of reduced nanoparticles in 4 minutes arc duration compared with 1 minute arc duration. A TEM image of the sample prepared at 4 minutes arc duration shows a narrow size distribution with 8 nm mean particle size. The plasmonic peak intensity of as prepared gold nanoparticles in 1 minute arc duration gradually increases due to seed mediation up to 6 hours. [ABSTRACT FROM AUTHOR]

Abstract: In this letter a simple procedure to synthesize sodium tungsten oxide nano-thick plates from WO3 films has been reported. WO3 films were grown by pulsed-laser deposition method and then heat treated at temperatures up to 560°C and times up to 120min. Slide glass was used as both substrate and sodium source simultaneously. XRD analysis revealed presence of an amorphous structure for as-deposited WO3 films. On the other hand, XRD showed formation of a monoclinic WO3 structure with annealing in lower temperatures and a triclinic Na0.5WO3.25 structure with annealing at higher temperatures. Intensity of the triclinic phase peaks enhanced drastically by rising annealing temperature and time. SEM results depicted presence of Na0.5WO3.25 nano-thick plates with thickness of about 160nm and width of about 3μm. Finally, XPS analysis revealed that heat treatment temperature does not affect tungsten valence state. [Copyright &y& Elsevier]

The properties of colloidal nanoparticles are the key parameters in the fabrication of inexpensive solar cells based on the solution methods. In this study, Different nanostructures of CuInS 2 (CIS) were successfully synthesized by a heating-up facile polyol-based method in which, polyols including diethylene glycol (DEG), ethylene glycol (EG), and glycerol (Gly) were chosen as both the solvent and the reductant. It is found that not only the indium precursor type but also the polyol solvent are greatly effective on the size, morphology and crystal phase of this sulfide ternary composition. Briefly, the heating-up synthesis using In(acac) 3 in DEG and Gly media, created nano-sized particles that arranged in a wurtzite crystalline structure. Resulted CIS particles from other indium salts are not suitable for making nanoparticle-based inks, since the micron-sized agglomerated particles are obtained which lack proper dispersion behavior for making inks. Image 1 • Different nanostructures of CuInS 2 were successfully synthesized by a heating-up facile polyol-based method. • The polyol solvent and indium salt have greatly effective on the size, morphology and crystal phase of CuInS 2 NPs. • Nano-sized particles are obtained only by the use of In(acac) 3 in diethylene glycol and glycerol solvents. [ABSTRACT FROM AUTHOR]

Abstract: We produced ZnO nanoparticles by high current electrical arc discharge of zinc electrodes in deionized (DI) water. X-ray diffraction (XRD) analysis shows formation of crystalline ZnO phase with hexagonal structure and 14nm single crystalline domain size. Dynamic light scattering (DLS) result indicates that at 5A arc current, the size of the particles is about 100nm and increases by increasing the arc current. Absorption spectroscopy of the samples obtained at different arc currents shows an absorption edge on 370nm which has a red shift by increasing the arc current. Band gap of the produced ZnO nanoparticles at 5A arc current corresponds to 3.8eV which decreases to 3.3eV by increasing the arc current up to 15A. The photoluminescence (PL) spectrum of the sample showed a strong ultraviolet (UV) emission peak around 383nm, corresponding to the ZnO nanoparticles. [Copyright &y& Elsevier]