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Hadrontherapy deals with the maximum energy deposition in the form of Bragg peak for energetic charged particles at a particular depth for killing cancerous cells. For planning hadrontherapy treatment accuracy in transport codes are primary demands of radiation oncology. In this work, we studied the dose deposition of the proton beam for the energy range of clinical interest i.e. 70 MeV to 240 MeV in water considering as tissue-equivalent material. The Bragg peak studies for different energy values are executed using Monte Carlo codes-based toolkit- GEANT4. We compared the four physics lists, the QGSP_BERT, the QBBC, the PhysListEmStandardNR (StandardNR), and emstandard_opt0, present in the Geant4 toolkit for avoiding uncertainty in the determination of dose deposition in the living cells which may cause damage of healthy cells. The StandardNR physics list is found suitable to get localized dose deposition in the form of smooth Bragg Curve. [ABSTRACT FROM AUTHOR]

This work presents the structural, optical and electrical properties of double perovskite oxide material Y2CuCoO5. The sample synthesized by hydrothermal method, sintered at 950°C temperatures crystallizes in pure orthorhombic phase formation with Pna21 space group. Samples were characterized using different techniques viz. X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Visible diffuse reflectance spectroscopy (DRS) and currentvoltage (I-V)characterization to study the structural, morphological, optical and electrical properties, respectively. From U-V visible DRS the indirect band-gap of value 1.3eV is estimated for double perovskite Y2CuCoO5. In I-V characterization straight-line behaviour is observed in the voltage range of -2.5V to 2.5V showing ohmic contact. [ABSTRACT FROM AUTHOR]

In the present work, the effective degradation of a commonly used textile dyemethylene blue (MB) in the presence of photocatalyst was investigated under visible light irradation. For this, pd-doped WO3 nanoparticles were synthesized via rapid co-precipitation method. The obtained sample was characterized via powder X-Ray diffractometry for crystallinity analysis and phase structure, SEM for morphological analysis,UV-vis spectroscopy for optical studies. The diffraction peaks obtained from XRD pattern are highly intense that shows crystallinity of the sample (average crystallite size of NPs are ~ 33 nm). The efficiency of degradation of the MB dye in the presence of W(0.99) Pd(0.01)O3photocatalyst was (~97% in 140 min) with rate constant (~0.021831 min-1). This shows Pd-doped WO3 has high sensitivity to absorb visible light due to its small band gap (Eg~2.45 eV). [ABSTRACT FROM AUTHOR]

Organic pollutants such as pesticides, dyes used in agriculture and industries pollute the water on large scale. In order to solve the problem of water pollution caused by the agricultural pesticides its degradation process has been studied. For this purpose, pure-ZnO and La doped ZnO nanoparticles were synthesized via co-precipitation method to observe photocatalytic response. Synthesized nanoparticles were unambiguously examined using x-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques for morphological and structural characterization. UV-visible spectroscopy and photoluminescence (PL) techniques for optical characterization. The average crystallite sizes of ZnO and La-doped ZnO NPs were ~55 nm and 35 nm, respectively. For photocatalytic activity, monocrotophos which is an insecticide is aimed to degrade in normal water under u.v light illumination. Enhancement in photocatalytic degradation efficiency is observed in La-doped ZnO due to enhancement in the surface area. [ABSTRACT FROM AUTHOR]

In this work, we present the computation of fragmentation cross-section of 28Si ion beam projectile incident on 12C target of depth 1.31 g/cm². The Monte Carlo (MC) code-based toolkit Geant4 written in C++ language is used for the simulation study. Three different models of physics, the Quantum Molecular Dynamics (QMD), the Leige Intranuclear cascade (INCL), and the Binary Cascade Model (BIC) models are activated separately in the Geant4 PhysicsList class. The computational results are comparatively analyzed with respect to experimental data. The fragmentation cross-section of Si ion for incident energies 266 A MeV, 344 A MeV, 560 A MeV, 765 A MeV, and 1147 A MeV is computed. These models regenerate experimental results of projectile fragmentation cross-section with good agreement taking acceptance angle of experimental technique into consideration. [ABSTRACT FROM AUTHOR]

In the present study, copper oxide (CuO) nanostructures have been synthesized at 140 °C for different aging periods, 1, 24, 48 and 96 hrs by hydrothermal method to investigate their effects on structural and optical properties. The X-ray diffractometer (XRD) pattern indicates the pure phase formation of CuO and the particle size, calculated from XRD data, has been found to be increasing from 21 to 36 nm for the samples synthesized at different aging periods. Field emission scanning electron microscope (FESEM) analysis also shows that the average diameter and length of these rectangular nano flakes increases with increasing the aging periods. Moreover Raman spectrums also confirm the phase formation of CuO. The optical band gaps calculated through UV-visible spectroscopy are found to be decreasing from 2.92 to 2.69 eV with increase in aging periods, 1 to 96 hrs, respectively. [ABSTRACT FROM AUTHOR]

In the present study, CR39 track etch detectors were calibrated using 600 A MeV Si14+ ion beam by coneheight distribution method using optical microscope DM 6000 M system installed with Leica QWin Plus software. The CR39 detectors just before and just after the target were calibrated. The response points were fitted with polynomials of second degree and all the points are within the limits of experimental errors. [ABSTRACT FROM AUTHOR]

In the present study, total and partial charge changing cross-sections of 300 A MeV Fe26+ ion beam in Al target were measured. The CR39 nuclear track detectors were used to identify the incident charged particles and their fragments using an automated image analyzer system installed with Leica QWin Plus software. The measured value of the total charge changing cross-section is σtot = (1663 ± 236) mb. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) and sulfur doped titanium dioxide (S-doped TiO2) nanoparticles are synthesized by Coprecipitation technique using titanium trichloride (TiCl3) as precursor, ammonium hydroxide (NH4OH) as solvent and sodium sulfite as source of sulfur. The X-ray diffraction (xrd) pattern reveals that TiO2 Nanoparticles are in anatase phase and anatase content decreases with increasing S-doping. The Differential Scanning Calorimetry (DSC) analysis elucidates the metastable anatase phase changes to stable rutile phase at 746 °C temperature. The UV/Vis study predicts larger band gap of TiO2 Nanoparticles as compare to bulk and blue shift with increasing S-doping. [ABSTRACT FROM AUTHOR]

CdTe thin films were deposited on glass at various substrate temperatures using vacuum evaporated technique. The X-ray diffraction analysis of vacuum evaporated cadmium telluride (CdTe) films reveals was polycrystalline in nature for the samples prepared at higher temperatures. Micro structural feature associated with the as deposited CdTe thin films were studied by Transmission Electron Microscope (TEM). A high density of trapping centers, responsible for grain boundary space-charge potential barriers, which oppose the passage of carriers from a grain to the neighboring ones, was explained from this analysis. [ABSTRACT FROM AUTHOR]