New NbCd<Subscript>2</Subscript> Phase in Niobium–Cadmium Coating Films

Solid solutions in the form of alloy coatings have been obtained for the first time in the Cd concentration range of 64.5% using ion-plasma sputtering and the codeposition of Nb and Cd ultrafine particles. This supports thermal fluctuation melting and the coalescence of fine particles. A coating of niobium and cadmium layers less than 2 nm thick at 68 at % Cd results in the formation of a new phase identified as NbCd2. The tetragonal fcc phase with lattice parameters a = 0.84357 nm and c = 0.54514 nm forms directly during film coating. XRD data for the identification of the intermetallic compound have been determined. The thermal stability of the NbCd2 intermetallic compound is limited by 200°C. The properties of the synthesized NbCd2 phase are typical of semiconductors.     

Investigation of the Sharkskin melt instability using optical Fourier analysis

An optical method allowing the characterization of melt flow instabilities typically occurring during an extrusion process of polymers and polymer compounds is presented. It is based on a camera-acquired image of the extruded compound with a reference length scale. Application of image processing and transformation of the calibrated image to the frequency domain yields the magnitude spectrum of the instability. The effectiveness of the before mentioned approach is shown on Styrene-butadiene rubber (SBR) compounds, covering a wide range of silica filler content, extruded through a Göttfert capillary rheometer. The results of the image-based analysis are compared with the results from the sharkskin option, a series of highly sensitive pressure transducers installed inside the rheometer. A simplified version of the code used to produce the optical analysis results is included as supplementary material. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48806.     

Iterative multiuser detector-decoding for nonbinary LDPC coded multicarrier MFSK systems

Telecommunication Systems - This paper investigates an iterative multiuser detection for nonbinary low density parity check (LDPC) coded multicarrier multiple level frequency shift keying system to...     

The Role of hOGG1 C1245G Polymorphism in the Susceptibility to Lupus Nephritis and Modulation of the Plasma 8-OHdG in Patients with Systemic Lupus Erythematosus

We investigated whether the C1245G polymorphism of human 8-oxoguanine glycosylase 1 (hOGG1) gene confers the susceptibility to systemic lupus erythematosus (SLE) occurrence of lupus nephritis and affects the plasma level of 8-hydroxy-2''-deoxyguanosine (8-OHdG) in patients with SLE. A total of 45 healthy controls and 85 SLE patients were recruited. The C1245G polymorphism of the hOGG1 gene was determined by direct sequencing. The frequency of occurrence of the hOGG1 1245 GG genotype in SLE patients was 31.8% (27/85), which is lower than that of healthy controls of 53.3% (24/45). Thirty-three (33/85, 38.8%) SLE patients developed lupus nephritis. Significantly, SLE patients harboring the hOGG1 1245 GG genotype had a higher incidence to develop lupus nephritis than did those harboring the hOGG1 1245 CC or CG genotype (15/27, 55.6% vs.18/58, 31.0%, p = 0.031). Divided into subgroups, SLE patients harboring the hOGG1 1245 GG genotype had the highest plasma levels of 8-OHdG among patients with all genotypes, with regard to the coexistence of lupus nephritis (p = 0.020, ANOVA), including those with nephritis harboring the hOGG1 1245 CC or CG genotypes (p = 0.037), those without nephritis harboring the hOGG1 1245 GG genotype (p = 0.050), and those without nephritis harboring the hOGG1 1245 CC or CG genotype (p = 0.054). We conclude that the C1245G polymorphism of hOGG1 may be one of the factors that confer the susceptibility to lupus nephritis and modulate the plasma level of 8-OHdG in patients with SLE.     

Investigation of increased removal rate during polishing of single-crystal silicon carbide

The application field of silicon carbide (SiC) as a next-generation compound semiconductor is expanding because of its significant advantages: high power, high frequency, low coefficient of thermal expansion, and high thermal conductivity. Many researchers have investigated SiC polishing for the manufacturing of semiconductor substrates using SiC. However, because SiC is a chemically and mechanically stable material, these researchers have faced difficulties due to its very low polishing rate (95–540 nm/h). Therefore, methods are required for increasing the material removal rate of SiC. The aim of this study was to investigate the increase in removal rate during the polishing of single-crystal SiC subjected to simultaneous polishing and dressing by using a diamond-impregnated polishing pad. Two types of pads—containing 1 and 5 wt% nanodiamond—were fabricated, and their performances were compared with that of a polyurethane polishing pad. A novel arrangement of conditioners was created in brazed diamond patterns, which were radially arranged in a cluster with 3–4 grits per cluster. Furthermore, a combined diamond disk was developed. The surface characteristics of the nanodiamond-impregnated pads, as well as the surface roughness, surface damage, and removal rate of the SiC polished with these pads and diamond disks, were investigated and compared with the corresponding attributes displayed by a polyurethane polishing pad and a conventional diamond disk. Experimental results showed that the removal rate of SiC with dressing was approximately 73 % higher than that of without dressing. The novel conditioner resulted in a dressing rate approximately two times higher and a removal rate approximately 38 % higher than those obtained by using the conventional diamond disk. In addition, SiC polishing tests revealed that the nanodiamond-impregnated polishing pads provided better surface roughness with no damage, as well as a removal rate approximately 2.5 times higher than that provided by the polyurethane polishing pad.     

Automatic recognition and suppression of holes on mold bases for finite element applications

Engineering with Computers - As the required accuracy of mold flow analysis has recently increased, it has become necessary to consider all components of a mold base and to generate solid meshes...