Accuracy and CPU time of JE-TLM,PLRC-TLM and CRC-TLM methods for plasma medium

The current density (JE), the piecewise linear recursive convolution (PLRC) and the constant convolution recursive (CRC) techniques are developed and integrated into the transmission line matrix (TLM) algorithm. A comparison of these three schemes according to the criteria of accuracy and CPU time is presented. Numerical experiments show that JE provides the most accurate solution and requires the least CPU time; PLRC is nearly as accurate but consumes more CPU time than CRC.     

Estimation of band alignment at CdS/Cu2ZnSnS4 hetero-interface by direct XPS measurements

This paper aims to estimate the band alignment to CdS/CZTS hetero-interface by direct X-ray photoelectron spectroscopy (XPS) measurements. XPS was used to determinate the valence-band offset (VBO) directly by determining the valence band positions at the hetero-interface. The conduction band offset (CBO) value was estimated based on the band gap measurements by UV/Visible spectroscopy and VBO measurements. The position of valence band (VB) changes close to the CdS-CZTS interface and the CBO is cliff-like. The band alignment diagram indicates that the CdS-CZTS interface heterojunction is type II.     

MS-based metabolomics revealing Bornean Sinularia sp. extract dysregulated lipids triggering programmed cell death in Hepatocellular carcinoma

Abstract

Soft coral, Sinularia sp. had been proven to inherit promising anti-cancer properties against variety of cancer. Current study, Sinularia sp. extract was introduced to Hepatocellular carcinoma (Hep 3B). Cell viability assay indicated the extract exhibit a dose and time dependent cytotoxicity. LC₅₀ exhibited the lowest at 72?h post treatment estimated as 45.3 µg/mL. Morphological alterations including nuclear condensation, cytoplasm shrinkage and deformed cellular shape in treated Hep 3B were observable. Chemometric analysis revealed hydrophobic metabolites were significantly altered. Elevated vitamin D and derivatives tend to up-regulation Ca²⁺ and ROS subsequently triggering apoptosis. Dysregulated glycerolipids may suggest that they were biotransformed to compensate the needs of phospholipids during cell damage. Perturbation of sphingolipids, ceramide and carbohydrate-conjugated ceramides species increased the release of pro-apoptotic components reside within mitochondria and promote programmed cell death in treated Hep 3B. To conclude, MS-based metabolomics enabled the characterization of Sinularia sp. extract-induced cell death.     

Mg<Subscript>2−<Emphasis Type="Italic">x</Emphasis></Subscript>Mn<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>SiO<Subscript>4</Subscript> compound obtained via sol–gel method: structural,morphological and electrochemical properties

Prospective cathode materials Mg_2-xMn _x SiO₄ (0.0?≤?x?≤?0.4) for magnesium-ion secondary battery were synthesized using sol gel method. Crystalline structure, morphology, particle size, electrical and electrochemical properties of the samples were investigated. X-ray diffraction patterns of the materials exhibited no extra peak for x?≤?0.6 indicated that Mg_2-xMn _x SiO₄ materials were successfully synthesized. Mn doping in magnesium site did not affect the formation of single phase, and this probably due to the low concentration of Mn to induces structural changes. Mn doping contributed to the enhancement of the electrochemical performance of Mg₂SiO₄. For this work, Mg_1.4Mn_0.6SiO₄ which possesses the largest unit cell volume, smallest charge transfer resistance, and highest conductivity value showed the most promising electrochemical performance compared to the other samples. These results indicated the suitability of the Mg_2-xMn _x SiO₄ to be exploiting further for potential applications as solid electrolytes in electrochemical devices and strengthen the fact that doping could be an effective way to enhanched the structural, electrical and electrochemical performance of materials.

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Influence of negative leader propagation on the triggering and guiding of high voltage discharges by laser filaments

The triggering and guiding of negative discharges using filaments induced by a femtosecond-terawatt laser pulse have been studied in sphere-plane gaps up to 4.5 meters. Fast-frame camera pictures allow the evaluation of the influence of the negative leader propagation on the triggering and guiding process. We show that the plasma channel can either trigger a space-leader discharge or act as a guiding path for the negative leader head. For the latter case the results suggest a linear dependence of the guided lengths up to 2.4 m, while the formation of a space-leader reduces this guided length by up to 50%. This effect is explained by the limited plasma lifetime of the filament that is measured to be about 1 μs.     

Effects of sintering temperature on the structure and electrochemical performance of Mg<Subscript>2</Subscript>SiO<Subscript>4</Subscript> cathode materials

The objective of the present study was to investigate the effects of sintering temperature on the structure and electrochemical performance of Mg₂SiO₄ cathode materials using sol-gel method. X-ray diffraction and Fourier-transform infrared analysis were used to study the structural properties of the materials. The temperatures applied in the sintering process influenced the structure, morphology, as well as particle size distribution of the Mg₂SiO₄. All samples sintered at temperatures of 900, 1000, and 1100 °C yielded pure Mg₂SiO₄ compounds consisting of orthorhombic crystalline phase with a space group of Pbnm. Particle size and lattice parameters of Mg₂SiO₄ samples increased with the increases of sintering temperature due to an increase of the nucleation and crystal growth rates. The cyclic voltammetry analysis showed the presence of redox reaction. This result shows that the Mg₂SiO₄ material has potential to be used as cathode materials in magnesium rechargeable batteries.     

Large Strain Shear Compression Test of Sheet Metal Specimens

A hybrid experimental-computational procedure to establish accurate true stress-plastic strain curve of sheet metal specimen covering the large plastic strain region using shear compression test data is described. A new shear compression jig assembly with a machined gage slot inclined at 35° to the horizontal plane of the assembly is designed and fabricated. The novel design of the shear compression jig assembly fulfills the requirement to maintain a uniform volume of yielded material with characteristic maximum plastic strain level across the gage region of the Shear Compression Metal Sheet (SCMS) specimen. The approach relies on a one-to-one correlation between measured global load–displacement response of the shear compression jig assembly with SCMS specimen to the local stress-plastic strain behavior of the material. Such correlations have been demonstrated using finite element (FE) simulation of the shear compression test. Coefficients of the proposed correlations and their dependency on relative plastic modulus were determined. The procedure has been established for materials with relative plastic modulus in the range 5?×?10^?4?<?(E _p /E)?<?0.01. It can be readily extended to materials with relative plastic modulus values beyond the range considered in this study. Nonlinear characteristic hardening of the material could be established through piecewise linear consideration of the measured load–displacement curve. Validity of the procedure is established by close comparison of measured and FE-predicted load–displacement curve when the provisional hardening curve is employed as input material data in the simulation. The procedure has successfully been demonstrated in establishing the true stress-plastic strain curve of a demonstrator 0.0627C steel SCMS specimen to a plastic strain level of 49.2 pct.