Determination of recombination lifetime in MOS structures by a sine voltage-sweep technique

A sine-voltage technique for measurements of recombination lifetime in metal oxide semiconductor (MOS) structures is proposed. When a fast sine-voltage sweep ramp is applied to the gate of an MOS capacitor a non-equilibrium depletion layer is formed and electron–hole generation starts in the space–charge–region and in the bulk. If the measurements are performed at elevated temperature so that quasi-neutral region generation rather than space charge region generation dominates, then the diffusion length, consequently the recombination lifetime, can be determined.     

Evaluation of strain rate sensitivity by constant load nanoindentation

Constant load measurements by nanoindentation offer the potential for measuring strain rate sensitivity from individual features and defects on a submicron scale. However, recent reports reveal a conflicting load dependence (both increasing and decreasing strain rate sensitivity with load) which has yet to be fully explained. In this study, constant load measurements on five materials (Zn, Al, Cu, Ti, and SiO₂) were conducted over a range of peak loads, and then compared with both constant strain rate results and conventional values in the literature. The load dependence was found to be caused by the increasing contribution of drift errors throughout the test. A proposed framework, involving higher loads, shorter hold and loading times, and a physically sound fitting method, was found to produce unambiguous results free from load dependencies, with improved correlations to conventional values and reduced standard deviations.     

Artisanal cheeses relying on spontaneous fermentation as sources of unusual microbiota – The example of the Bulgarian ‘mehovo sirene’ skin bag cheese

The Bulgarian ‘mehovo sirene’ cheese is a type of regional artisanal cheese prepared from raw ewe milk in a skin bag relying on spontaneous fermentation. A metagenomics study revealed an unusual microbiome comprising beneficial bacteria such as Staphylococcus equorum, Lactococcus lactis, Streptococcus thermophilus, Lactobacillus delbrueckii, Lactobacillus kefiranofaciens, Lactococcus raffinolactis, Lactiplantibacillus plantarum, Limosilactobacillus fermentum and Loigolactobacillus coryniformis. Our findings suggest that ‘mehovo sirene’ could have some functional food properties and is a source of beneficial microorganisms.