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In this study, iron sulphide thin films were prepared by simple and low-cost chemical spray-pyrolysis method using tilt deposition with a spraying angle of 45° and substrates temperature of 200°C. The precursors were iron chloride salt (FeCl3) and thiourea. After the preparation process, some of the samples are annealed at a temperature 400°C for 30 min. It was found that the as-deposited iron sulphide thin films (without annealing) had an amorphous structure, which gave higher absorption coefficient (2 × 105 cm−1) for thin film thickness 400 nm. This study also presents a novel method to obtain polycrystalline FeS2 thin films with pyrite phase and optimum energy bandgap and high absorption coefficient. A thin film of iron sulphide was also deposited on fluorine-doped tin oxide glass to work as a counter electrode for dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

This paper is conducted for identifying the parasite which collected during regular routine inspection for the hygienic condition and health status of fish in 2019 at the central fish market shops at Jubail city, Saudi Arabia. Samples from an orange spotted grouper (Epinephelus coioides) fish showed heavy black streaks between the muscle fibers that was considered unmarketable and rejected by the consumer after had been cut and prepared for sealing. The black discolorations were in the form of heavy diffused focal black spots or forming threads of variable sizes embedded in the entire whole-body musculature of the fish. These samples were subjected to parasitological and pathological evaluation. The parasitological examination of the affected muscular tissues revealed infection by Huffmanela spp. eggs. The parasitic infection was identified on the bases of the morphological and ultra-structural characters of the eggs. The examination of the affected fish showed multifocal black parasitic remnants between the muscle fibers. The parasitic fragments were distributed all over the fish flesh either superficially in subcutaneous area or deep inside the muscular tissue and they have been concentrated in the flesh around the vertebral column. In conclusion; this case report confirmed the occurrence of Huffmanela spp. infection in the muscles of Epinephelus coioides by using light and scanning electron microscopy. Further molecular assessment is recommended. [ABSTRACT FROM AUTHOR]

The novelty of this work is to fabricate the double-walled (DW) TiO2 nanotube arrays (TNAs) by an anode oxidation method with NH4F-based electrolyte and Zinc counter electrode (CE, c-Zn) and to investigate the photodegradation performance of these TNAs. The structural, optical, and photodegradation performance of TNAs with c-Zn material have been compared to the properties of TNAs with the other two CEs like c-Pt (Platinum) and c-Ti (Titanium). The counter electrode has a tremendous influence on the structural properties and geometrical features of TNAs. The TNAs fabricated with c-Zn have the red-shifted absorption edge with two bandgaps such as 3.15 and 1.78 eV. Interestingly, the TNAs with c-Zn are found as the DW TNAs with outer diameter of 130 ± 3 nm, thinner outer wall thickness of 12 ± 2 nm, and thicker inner wall thickness of 30 ± 2 nm. The photodegradation performance varies with different counter electrodes during the deposition of TNAs by the anode oxidation method. The TNAs sample prepared with c-Zn has shown the highest roughness value of 305.0 nm, photodegradation efficiency of 97.0%, and the rate constant value of 0.00985 min−1 than the other TNAs with c-Pt, c-Ti, and other researcher's data. Moreover, the optical, structural, and surface morphological properties of TNAs have correlated with the photodegradation performance of TNAs prepared with various counter electrodes during deposition. [ABSTRACT FROM AUTHOR]

Porous Ti-Nb-xSn shape memory alloys (SMAs) are fabricated by microwave sintering technology. The microstructures exhibit needle-like morphologies, β(N) (normal straight and crossed needles along with needle-like morphology that resembles spaghetti or irregular lines with α-phases in between) as well as plate-like morphologies [normal straight plate-like morphology, α′′ and dendritic plate-like morphology, β(D)]. Increases in Sn addition significantly induce an increase in the density of the α-phase. XRD patterns exhibited three phases, namely the β-main phase with smaller intensities of α′′ and α. Further, the addition of 0.25% Sn led to more effective improvement in the intensity of the α′′-phase compared with 0.5% and 1.5% Sn addition. Additions of Sn also enhanced the fracture strength and its corresponding strain along with the shape memory effect (SME), where the best enhancement was achieved at 0.25% Sn. The corrosion rate (Ri) was reduced by rising Sn content, while both corrosion resistance and antibacterial zones were increased. The lower elastic modulus, as well as the robust mechanical properties and bioactivity, made these SMAs rather suitable for biomedical application purposes, where the low elastic modulus had value in terms of avoiding the problem of "stress shielding." [ABSTRACT FROM AUTHOR]

Double-gate (DG) metal-oxide-semiconductor field-effect transistors (MOSFETs) with GaN channel material are very promising for use in future high-performance low-power nanoscale device applications. In this work, GaN-based sub-10-nm DG-MOSFETs with different gate work function, Φ, were designed and their performance evaluated. Short-channel effects (SCEs) were significantly reduced by introduction of gates made of dual metals. Use of gold at the source side, having higher Φ (ΦAu=5.11eV) compared with aluminum (ΦAl=4.53eV), at the drain side enhanced the gate control over the channel and screened the effect of the drain on the channel. Dual-metal (DM) DG-MOSFETs showed better results in the nanoscale regime and were more robust to SCEs. Therefore, GaN-based sub-10-nm DM DG-MOSFETs are suitable candidates for use in future complementary metal-oxide-semiconductor (CMOS) technology. [ABSTRACT FROM AUTHOR]

This paper elucidates the details of exciton localization dynamics in InGaN/GaN and GaN/AlInN quantum wells (QWs) using Monte Carlo simulation for a wide range of temperatures (10–300 K). We find that the phonon-induced variation of exciton lifetimes has remarkable effects on the photoluminescence (PL) peak position and the line-width. The red-shift of PL peak position at high temperature is clarified. The combined effects of phonon-induced radiative lifetime of excitons and the band-gap shrinkage at high temperature show the most reasonable agreement with the experimentally observed red-shift of the PL peak position. We have also quantitatively explained the temperature dependence of the W-shaped line-width in both InGaN/GaN and GaN/AlInN QWs. These results are highly significant to understand the emission properties of III-nitride QWs optoelectronic devices. [ABSTRACT FROM AUTHOR]