Effect of Phosphate-Bridged Monomer on Thermal Oxidative Behavior of Phthalonitrile Thermosets.

Phthalonitrile thermosets are known for their excellent mechanical, physico-chemical, and fire-retardant properties, making them attractive for aerospace and mechanical engineering applications. When producing and applying phthalonitrile-based structural parts, it is essential to consider aspects such as processability and the long-term stability of the material's properties at high temperatures. In our previous studies, we demonstrated that resins containing phosphate-bridged bisphthalonitrile monomers are easily processable due to their low melting temperature and wide processing window.

MORPHOLOGICAL ASSESSMENT OF THE LUNGS IN POST-COVID-19 SYNDROME: ANALYSIS OF AUTOPSY MATERIAL.

Objective: The aim was to reveal the morphological features of the lungs in post-COVID-19 syndrome.

Patients And Methods: Materials and methods: The material of the study was autopsy material - fragments of the lung tissue from 96 deceased (59 men and 37 women). During the lifetime, all patients had in anamnesis COVID-19 of varying severity, and after the treatment of this infection, they had various manifestations of respiratory failure until death.

Analysis of Aluminum Oxides Submicron Particle Agglomeration in Polymethyl Methacrylate Composites.

Agglomeration of distributed particles is the main problem in polymer composites reinforced with such particles. It leads to a decrease in mechanical performance and its poor reproducibility. Thus, development of methods to address the agglomeration of particles is relevant.

Design and Modeling of a Fully Integrated Microring-Based Photonic Sensing System for Liquid Refractometry.

The design of a refractometric sensing system for liquids analysis with a sensor and the scheme for its intensity interrogation combined on a single photonic integrated circuit (PIC) is proposed. A racetrack microring resonator with a channel for the analyzed liquid formed on the top is used as a sensor, and another microring resonator with a lower Q-factor is utilized to detect the change in the resonant wavelength of the sensor. As a measurement result, the optical power at its drop port is detected in comparison with the sum of the powers at the through and drop ports.

Fast-Processable Non-Flammable Phthalonitrile-Modified Novolac/Carbon and Glass Fiber Composites.

Phthalonitrile resins (PN) are known for their incredible heat resistance and at the same time poor processability. Common curing cycle of the PN includes dozens hours of heating at temperatures up to 375 °C. This work was aimed at reducing processing time of phthalonitrile resin, and with this purpose, a novolac oligomer with hydroxyl groups fully substituted by phthalonitrile moieties was synthesized with a quantitative yield.