Bent crystals obtained by low energy plasma enhanced chemical vapour deposition for medical applications

This paper presents bent crystals obtained by low energy plasma enhanced chemical vapour deposition technique, which could be further improved for medical applications to focus gamma rays. Medical imaging plays an important role in the field of nuclear medicine and the use of bent crystals to focus energetic gamma rays used for imaging of radioactivity in the human body is our interest. An innovative technique to obtain curved crystals is proposed in this work. Surface profilometry measurements were done to find the curvature of curved crystals

NANOMECHANICAL CHARACTERIZATION OF INDIUM PHOSPHIDE EPILAYER USING NANOINDENTATION TECHNIQUE

The Nanomechanical characteristics of InP epilayer grown on GaAs (100) substrate is studied. The mechanical characteristics of the material such as hardness, modulus of elasticity, stiffness, contact depth etc. were studied by Nanoindentation technique with different probe geometries like Berkovich and Vickers. The results show significant variation in the mechanical parameters with respect to the tip geometry and the measured hardness values were observed to increase with the applied load

Annealing study and thermal investigation on bismuth sulfide thin films prepared by chemical bath deposition in basic medium

This is a post-peer-review, pre-copyedit version of an article published in Applied Physics A 124.2 (2018): 166. The final authenticated version is available online at: http://doi.org/10.1007/s00339-018-1584-7Bismuth sulfide thin films were prepared by chemical bath deposition using thiourea as sulfide ion source in basic medium. First, the effects of both the deposition parameters on films growth as well as the annealing effect under argon and sulfur atmosphere on as-deposited thin films were studied. The parameters were found to be influential using the Doehlert matrix experimental design methodology. Ranges for a maximum surface mass of films (3 mg cm-2) were determined. A well crystallized major phase of bismuth sulfide with stoichiometric composition was achieved at 190°C for 3 hours. The prepared thin films were characterized using Grazing Incidence X-ray diffraction (GIXRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray analysis (EDX). Second, the band gap energy value was found to be 1.5 eV. Finally, the thermal properties have been studied for the first time by means of the electropyroelectric (EPE) technique. Indeed, the thermal conductivity varied in the range of 1.20 - 0.60 W m-1 K-1 while the thermal diffusivity values increased in terms of the annealing effect ranging from 1.8 to 3.5 10-7 m2s-1This work was financially supported by the Tunisian Ministry of Higher Education and Scientific Research and by the WINCOST (ENE2016-80788-C5-2-R) project funded by the Spanish Ministry of Economy and Competitivenes

A facile chemical conversion synthesis of Sb2S3 nanotubes and the visible light-driven photocatalytic activities

We report a simple chemical conversion and cation exchange technique to realize the synthesis of Sb2S3 nanotubes at a low temperature of 90°C. The successful chemical conversion from ZnS nanotubes to Sb2S3 ones benefits from the large difference in solubility between ZnS and Sb2S3. The as-grown Sb2S3 nanotubes have been transformed from a weak crystallization to a polycrystalline structure via successive annealing. In addition to the detailed structural, morphological, and optical investigation of the yielded Sb2S3 nanotubes before and after annealing, we have shown high photocatalytic activities of Sb2S3 nanotubes for methyl orange degradation under visible light irradiation. This approach offers an effective control of the composition and structure of Sb2S3 nanomaterials, facilitates the production at a relatively low reaction temperature without the need of organics, templates, or crystal seeds, and can be extended to the synthesis of hollow structures with various compositions and shapes for unique properties

Spectroscopic investigation of BiSeI, SbSeI compounds and BiSbS_xSe_l-xI solid solutions

373-376The compounds such as SbSeI, BiSeI and solid solutions of BiSbSxSe1-xI (x = 0.2 to 0.8 mol fractions) are grown from vapour by chemical vapour transport method. The IR and Raman spectra were recorded in the range 600-50 cm-1. The IR spectra reveal that the frequency modes are sensitive to selenium substitution and the Raman spectra show that the bands below 200 cm-1 are halogen sensitive

nIαg-closed sets and Normality via nIαg-closed sets in Nano Ideal Topological Spaces

We have defined a new generalised closed set called nIαg closed sets in nano ideal topological spaces. Also, association of nIαg closed sets with various existing closed sets are studied. Characterisations and equivalent conditions of nIαg closed sets are proved. Normality via nIαg closed sets are also been studied in this paper

Growth of some group V-VI-VII compounds from the vapour

Crystals of bismuth oxyiodide (BiOI), bismuth oxychloride (BiOCl) and bismuth seleno-iodide (BiSeI) have been successfully grown from the vapour. The BiOCl platelets are transparent, while BiOI and BiSeI platelets exhibit mirror like faces with metallic lustre. These crystals are semiconductors with highly anisotropic properties due to the layer structure. Interesting morphological features of the crystals were studied by optical and scanning electron microscopy. Optical interferograms of BiOCl crystals were analysed. Dielectric studies of BiSeI crystals showed a new phase transition at 410 K