Nanohardness and Young's Modulus of Pb1-xCdxTe Crystals Grown by the SSVG and MBE Methods.

The nanohardness and Young's modulus of Pb1-xCdxTe single crystals prepared by the self-selecting vapor growth (SSVG) method and thick, MBE-grown layers with a total Cd content of up to 7% metal atoms were studied using the nanoindentation technique; the nanohardness and Young's modulus were calculated by the Oliver and Pharr method. Significant hardening of SSVG crystals with increasing number of Cd atoms replacing Pb atoms in the formed solid solution was observed, and low anisotropy of the nanohardness and Young's modulus were found. The CdTe solubility limit in the solid solution grown using an MBE equal to 2.1% was demonstrated; even for the significantly higher total Cd concentration in the layer, the possible presence of precipitates was not detected. Significant differences were found for both the energy of elastic crystal deformation and Young's modulus determined for samples grown using the two methods. An increase in nanohardness with an increase in the number of Cd atoms outside the cation sublattice was shown. The different ratios of hardening mechanisms acting simultaneously in the analyzed crystals in various ranges of Cd concentrations were demonstrated and discussed. The observed effects were attributed to the much higher concentration of point defects in MBE-grown layers than in SSVG crystals, in particular, the interstitial Cd-Te vacancy complexes effectively hampering nucleation and propagation of dislocations in the former case.

The Prohibition of Suicide and Its Theological Rationale in Catholic Moral and Canonical Tradition: Origins and Development.

This paper analyzes the nuances of the Roman Catholic Church's opposition to suicide. First, we analyze biblical suicide cases, showing that these were not usually met with clear condemnation. Next, we show the development of the Roman Catholic Church's moral teachings, with special attention to Augustine. The canon law of the Middle Ages still made some distinctions regarding motivation, but at this point, Roman Catholic funerals started to be refused to those having committed suicide as discouragement to others. This was maintained by the Council of Trent. In the twentieth century, the Roman Catholic Church followed modern psychiatry in attributing suicide to mental illness, and the ban on Roman Catholic funerals was lifted. Currently, the Roman Catholic Church tries to discourage suicide while accompanying people in need.

Characteristics of the Structure, Mechanical, and Tribological Properties of a Mo-Mo2N Nanocomposite Coating Deposited on the Ti6Al4V Alloy by Magnetron Sputtering.

Mo-Mo2N nanocomposite coating was produced by reactive magnetron sputtering of a molybdenum target, in the atmosphere, of Ar and N2 gases. Coating was deposited on Ti6Al4V titanium alloy. Presented are the results of analysis of the XRD crystal structure, microscopic SEM, TEM and AFM analysis, measurements of hardness, Young's modulus, and adhesion. Coating consisted of α-Mo phase, constituting the matrix, and γ-Mo2N reinforcing phase, which had columnar structure. The size of crystallite phases averaged 20.4 nm for the Mo phase and 14.1 nm for the Mo2N phase. Increasing nitrogen flow rate leads to the fragmentation of the columnar grains and increased hardness from 22.3 GPa to 27.5 GPa. The resulting coating has a low Young's modulus of 230 GPa to 240 GPa. Measurements of hardness and Young's modulus were carried out using the nanoindentation method. Friction coefficient and tribological wear of the coatings were determined with a tribometer, using the multi-cycle oscillation method. Among tested coatings, the lowest friction coefficient was 0.3 and wear coefficient was 10 × 10-16 m3/N∙m. In addition, this coating has an average surface roughness of RMS < 2.4 nm, determined using AFM tests, as well as a good adhesion to the substrate. The dominant wear mechanism of the Mo-Mo2N coatings was abrasive wear and wear by oxidation. The Mo-Mo2N coating produced in this work is a prospective material for the elements of machines and devices operating in dry friction conditions.

Light-Curing Volumetric Shrinkage in Dimethacrylate-Based Dental Composites by Nanoindentation and PAL Study.

Light-curing volumetric shrinkage in dimethacrylate-based dental resin composites Dipol® is examined through comprehensive kinetics research employing nanoindentation measurements and nanoscale atomic-deficient study with lifetime spectroscopy of annihilating positrons. Photopolymerization kinetics determined through nanoindentation testing is shown to be described via single-exponential relaxation function with character time constants reaching respectively 15.0 and 18.7 s for nanohardness and elastic modulus. Atomic-deficient characteristics of composites are extracted from positron lifetime spectra parameterized employing unconstrained x3-term fitting. The tested photopolymerization kinetics can be adequately reflected in time-dependent changes observed in average positron lifetime (with 17.9 s time constant) and fractional free volume of positronium traps (with 18.6 s time constant). This correlation proves that fragmentation of free-volume positronium-trapping sites accompanied by partial positronium-to-positron traps conversion determines the light-curing volumetric shrinkage in the studied composites.