Characterization of Fibers Prepared by Centrifugal Spinning from Biotechnologically Derived Chicken Gelatin.

The application of biopolymer-based materials is increasing due to better sustainability and environmental protection properties. Gelatin fibers have a specific surface and high porosity, which is why their use in medicine and the food industry is being researched. This article explores the potential of centrifugal spinning to produce gelatin fibers.

Reactive oxygen species and their role in the andrological factor of couple fertility.

Reactive oxygen species play a significant role in male fertility and infertility. They are essential for physiological processes, but when their concentration becomes excessive, they can be a cause of various sperm pathologies. Seminal leukocytes and pathologically abnormal sperm are the primary sources of oxygen radicals in ejaculate.

Production of Modified Composite Nanofiber Yarns with Functional Particles.

The study focused on the production of modified composite nanofiber yarns with fine functional particles. A device that incorporates fine functional particles into a nanofiber yarn wrapper was specially developed, which ensures the continuous production of modified yarn. It was demonstrated during the study that the specially designed equipment could be used effectively for incorporating fine functional particles into the nanofiber packaging, thus creating a unique yarn with high application potential.

Residual stress determination by the layer removal and X-ray diffraction measurement - correction method.

Very often a manufacturing process is followed by some surface treatment. Such a process induces residual stress into the manufactured component. Compressive residual stress is desirable for enhancing the fatigue properties of the component.

Optimization of the Spinneret Rotation Speed and Airflow Parameters for the Nozzleless Forcespinning of a Polymer Solution.

This paper addresses the changing of the process parameters of nozzleless centrifugal spinning (forcespinning). The primary aim of this study was to determine the dependence of the final product on the dosing of the polymer, the rotation speed of the spinneret and the airflow in order to determine the extent of the technological applicability of aqueous polyvinyl alcohol (PVA) and its modifications. PVA was chosen because it is a widely used polymeric solution with environmentally friendly properties and good biodegradability.

The Optimization of Alternating Current Electrospun PA 6 Solutions Using a Visual Analysis System.

The electrospinning process that produces fine nanofibrous materials have a major disadvantage in the area of productivity. However, alternating current (AC) electrospinning might help to solve the problem via the modification of high voltage signal. The aforementioned productivity aspect can be observed via a camera system that focuses on the jet creation area and that measures the average lifespan.

Effect of Underload Cycles on Oxide-Induced Crack Closure Development in Cr-Mo Low-Alloy Steel.

Underload cycles with small load amplitudes below the fatigue crack growth threshold are dominantly considered as insignificant cycles without any influence on fatigue lifespan of engineering structural components. However, this paper shows that in some cases these underload cycles can retard the consequent crack propagation quite significantly. This phenomenon is a consequence of oxide-induced crack closure development during cyclic loading below the threshold.

Effect of Solution Annealing on Fatigue Crack Propagation in the AISI 304L TRIP Steel.

Fatigue crack propagation in near-threshold regime was studied in the 304L austenitic stainless steel in two microstructural states: as-received (AR) with finer microstructure and low susceptibility to the transformation-induced plasticity (TRIP) effect, and solution-annealed (SA) with coarser microstructure and higher susceptibility to TRIP. At the load ratio = 0.1 the threshold was higher in the SA state than in the AR state due to coarser grains and possibly the TRIP effect.

Desire for Parenthood and Associated Trends in Czech Lesbian Women.

Introduction: Worldwide, there are more lesbians who chose to have children in the context of a same-sex relationship than ever before. The Czech studies focusing on this issue, including the analysis of methods of conception, are limited.

Aim: We aimed to examine the changes over time in the desire of Czech lesbian women for children and to analyze their chosen methods of conception.

Influence of coating technology and thermal annealing on the optical performance of AR coatings in iodine-filled absorption cells.

In this contribution, we investigate the properties of antireflective coatings on iodine-filled absorption cell windows. These coatings are subject to high temperatures during the cell production process and are in direct contact with the absorption medium, which influences their optical performance. We tested the thermal resistance of TiO- and TaO- based coatings produced using conventional electron beam evaporation (e-beam) and ion-assisted deposition (PIAD).

Fabrication of dual-functional composite yarns with a nanofibrous envelope using high throughput AC needleless and collectorless electrospinning.

Nanotechnologies allow the production of yarns containing nanofibres for use in composites, membranes and biomedical materials. Composite yarns with a conventional thread core for mechanical strength and a nanofibrous envelope for functionality, e.g.

Needleless coaxial electrospinning: A novel approach to mass production of coaxial nanofibers.

Herein, we describe a simple spinneret setup for needleless coaxial electrospinning that exceeds the limited production capacity of current approaches. The proposed weir spinneret enables coaxial electrospinning from free liquid surface. This approach leads to the formation of coaxial nanofibers with higher and uniform shell/core ratio, which results in the possibility of better tuning of the degradation rate.