Microstructure of calcium sulfoaluminate mortar with basalt additive at elevated temperature

This article is motivated by ensure the fire safety of the building and deeper understanding on special cements under elevated temperature loads. Knowledge about influence of high temperatures on calcium sulfoaluminate cement (CSA) based materials has crucial impact on ensuring the fire safety of the buildings. CSA based composites are dedicated to special usage in demanding infrastructure constructions. As there is no or insufficient evidence on the influence of heat on calcium sulfoaluminate materials, this article is motivated to extend current literature knowledge on CSA microstructures at higher temperatures up to 800oC. Recognising the effect of high temperature is particularly important given the significant differences between CSA and Ordinary Portland Cement (OPC). Evidence shows influence of mixture proportion on composite structure, filler-matrix bond, and matrix behaviour during temperature exposure. Obtained results might help in understanding phenomena occurring within material under temperature load and determine next research directions in this area

YAQQ: Yet Another Quantum Quantizer -- Design Space Exploration of Quantum Gate Sets using Novelty Search

In the standard circuit model of quantum computation, the number and quality of the quantum gates composing the circuit influence the runtime and fidelity of the computation. The fidelity of the decomposition of quantum algorithms, represented as unitary matrices, to bounded depth quantum circuits depends strongly on the set of gates available for the decomposition routine. To investigate this dependence, we explore the design space of discrete quantum gate sets and present a software tool for comparative analysis of quantum processing units and control protocols based on their native gates. The evaluation is conditioned on a set of unitary transformations representing target use cases on the quantum processors. The cost function considers three key factors: (i) the statistical distribution of the decomposed circuits' depth, (ii) the statistical distribution of process fidelities for the approximate decomposition, and (iii) the relative novelty of a gate set compared to other gate sets in terms of the aforementioned properties. The developed software, YAQQ (Yet Another Quantum Quantizer), enables the discovery of an optimized set of quantum gates through this tunable joint cost function. To identify these gate sets, we use the novelty search algorithm, circuit decomposition techniques, and stochastic optimization to implement YAQQ within the Qiskit quantum simulator environment. YAQQ exploits reachability tradeoffs conceptually derived from quantum algorithmic information theory. Our results demonstrate the pragmatic application of identifying gate sets that are advantageous to popularly used quantum gate sets in representing quantum algorithms. Consequently, we demonstrate pragmatic use cases of YAQQ in comparing transversal logical gate sets in quantum error correction codes, designing optimal quantum instruction sets, and compiling to specific quantum processors

Morphology and Structure of Al2O3 + Graphene Low-Friction Composite Coatings

Recently, graphene and its derivatives have been of particular interest as a solid lubricant to reduce friction. The aim of this study was to investigate the morphology and structure of low-friction Al2O3 coatings containing reduced graphene oxide (rGO). Using two types of rGO, alumina coatings were produced by the sol–gel dip-coating method and characterized in terms of morphology and structure using SEM and AFM microscopy and Raman spectroscopy. It was found that composite Al2O3 + rGO coatings had diversified morphology depending on the type of graphene used. The dip-coating method used for deposition had a large impact on the morphology and contributed to the orderly arrangement of rGO nanoplates in the coating matrices. It was also shown that there is a correlation between the shape and spatial orientation of nanoplates and the tribological properties of coatings. The structural studies showed differences in the number of graphene defects in the coatings, which may indicate the chemical bonding of graphene with the alumina matrices. These differences may also be responsible for divergences in the tribological properties of the coatings depending on the type of graphene. All our findings indicate the key role of an appropriate balance between the parameters of composite coating production in terms of the desired tribological properties

Functional Ceramic Coatings

Modern materials engineering, just like other areas of today’s science and technology, requires a comprehensive and balanced approach that takes into account all factors that affect not only the design and functional properties of materials, but also their economic profitability and rational management of the available resources [...]</jats:p

Functional Ceramic Coatings

Modern materials engineering, just like other areas of today’s science and technology, requires a comprehensive and balanced approach that takes into account all factors that affect not only the design and functional properties of materials, but also their economic profitability and rational management of the available resources [...

A New Microstructural Concept and Water-Free Manufacturing of an Al2O3-Based Refractory Material for Auxiliary Equipment of Sintering Furnaces

This study presents the development of a novel alumina-based ceramic composite designed for refractory applications in auxiliary components of sintering furnaces. The innovative concept relies on a three-phase microstructural architecture: a fine-grained alumina matrix improves cohesion, coarse particles act as crack propagation barriers, and spherical granules are intentionally introduced to increase porosity while preserving mechanical strength. This design reduces thermal capacity, enhancing the material&rsquo;s energy efficiency under high-frequency thermal cycling and offering potential for operating cost reduction. A further novelty is the water-free forming process, which eliminates issues related to drying and deformation. The material was characterized using scanning electron microscopy (SEM), mechanical strength testing, and refractoriness under load (RUL) analysis to establish the structure&ndash;property relationships of the developed composite. The results demonstrate that the developed spherical alumina-based composite possesses excellent thermal and mechanical properties, making it a promising candidate for high-temperature industrial applications, particularly as auxiliary refractory plates

Antibacterial Properties of Zn Doped Hydrophobic SiO2 Coatings Produced by Sol-Gel Method

Bacteria existing on the surfaces of various materials can be both a source of infection and an obstacle to the proper functioning of structures. Increased resistance to colonization by microorganisms can be obtained by applying antibacterial coatings. This paper describes the influence of surface wettability and amount of antibacterial additive (Zn) on bacteria settlement on modified SiO2-based coatings. The coatings were made by sol-gel method. The sols were prepared on the basis of tetraethoxysilane (TEOS), modified with methyltrimethoxysilane (MTMS), hexamethyldisilazane (HMDS) and the addition of zinc nitrate or zinc acetate. Roughness and surface wettability tests, as well as study of the chemical structure of the coatings were carried out. The antibacterial properties of the coatings were checked by examining their susceptibility to colonization by Escherichia coli. It was found that the addition of zinc compound reduced the susceptibility to colonization by E. coli, while in the studied range, roughness and hydrophobicity did not affect the level of bacteria adhesion to the coatings.</jats:p