SOUTHERN JOURNAL OF SCIENCES

Introduction: Thermal insulating coatings are increasingly being introduced into construction practice for internal and external finishing enclosing structures and pipelines. Thermal insulation coatings are usually made based on polymer binder and mineral fillers. The durability and stability of the properties of heat-insulating materials depend on the type of binder. As a rule, polymers are used as a binder: epoxy resin; silicone rubber; urea-formaldehyde resins; aqueous dispersed polymers - styrene-butadiene, polyvinyl acetate, and acrylate (acrylic and styrene-acrylic). The quality indicator of binders can be assessed by the influence of the seasonality of climatic impact, and as a result, the best elastic strength characteristics of binders can be established after one month to a year of field tests. Aim: To determine the influence of climatic factors on the change in the elastic-strength indicators of epoxy polymers binders used in liquid thermal insulation coatings. Methods: A tensile testing machine of the AGS-X series with the TRAPEZIUM X software was used for mechanical tests. The tests were carried out in accordance with GOST 11262-2017 (ISO 527-2: 2012) "Plastics. Tensile test method". Results and Discussion: The paper discusses the results of experimental studies of the compositions of polymer binders and their resistance to various climatic factors, which will later be used as a polymer binder for thermal insulation coatings based on fine mineral granular systems. Conclusions: When analyzing the changes in the characteristics of polymer samples after exposure to climatic factors, it was found that compositions based on Etal-247 epoxy resin, cured with amine hardeners Etal-1440N, Etal-1460, Etal-1472, and Etal-45M, demonstrate the best elastic strength characteristics after one year of full-scale tests. The high stability of the indicators under consideration allows us to conclude that the use of Etal-247 resin as a base leads to creating of the most climate-resistant epoxy coatings.

Background: A client requested that the study group help determine suitable locations for a drilling regime on his lot, located on an upslope rocky knoll in Lawu Estate, Minna, Nigeria. There is no luxury of conducting an unimpeded wide-area survey for this housing Estate, as it is built up almost entirely. Therefore, the constrained area to be surveyed necessitated the adoption of the "electrical drilling," or vertical electrical sounding, mode of the geoelectrical method to satisfy the client's inquiry. Aim: To carry out a purpose-specific survey to pinpoint the best location in a built-up property at the upmarket Lawu Estate that would be suitable for a drilling regime targeted for household consumption. The specific objectives are to determine the subsurface layer structure, to identify fracture zones with potential for water accumulation, and to estimate the depths of potential aquifers. Methods: The survey crew reconnoitered the study area to georeference locations for the VES survey within the 30 m x 20 m lot. Owing to the extensive build-up at this lot, only a four-point traverse along the 30-metric dimension of the building's frontage was demarcated in the northeasterly direction, thereby limiting the survey crew's desire to define an appropriate survey grid. The VES data acquisition followed the "traditional" sequence of Schlumberger array layout measurements, in which the current and potential probes are maintained at the same relative spacing and the whole spread is progressively expanded about a fixed central point. Results: Log-log and pseudosection plots were generated from the acquired data, from which the conventional three-layer structure is deciphered, with a desired 193 Ωm for VES Station 4 at the third layer. Discussion: The acquired and processed data for this study were subjected to a suite of empirical rules-of-thumb procedures for interpreting VES data in the Nigerian Basement Complex geological province, with VES Station 4 showing the most encouraging 100% result. Conclusion: Drilling to a depth of 100 m at Station 4 is recommended based on the identified fractured basement at this depth.

Background: Despite innovations in orthopedic dentistry, the manufacture of removable dentures belongs to the most popular orthopedic care category. Removable dentures are combined stimuli that affect the mucous membrane and neuro-receptor apparatus. Acrylic plastic prostheses, widely used in prosthetic dentistry, have a negative side mechanical, chemical-toxic, sensitizing, and thermal insulating effect on oral tissue and prosthetic impression area. This is often complicated by a violation of the biocenosis of the oral cavity, the growth of pathogenic microflora that releases toxins, especially an increase in the number of yeast colonies that irritate the oral mucosa and prosthetic stomatitis. According to the WHO, one-fifth of the world s population suffers or has suffered various candidiasis forms at least once. The worldwide increase in the incidence of the disease is primarily related to the fact that this infection is opportunistic, more than half of the world s population is a carrier of fungi of this kind, i.e., in most cases, it is an endogenous infection, which makes candidiasis different from other opportunistic mycoses. Aims: The purpose of this study was to study the prevalence of candidiasis in patients using removable dentures and to evaluate the effectiveness and prevention of candidiasis treatment. Methods: 100 patients with oral candidiasis of various age groups from 45 to 65 years were observed. Of these, 60 patients with removable plate prostheses; 40 patients with partially removable prostheses. Results and Discussion: Chronic forms of candidiasis were diagnosed in 40 patients and with exacerbation of chronic forms of candidiasis-60 people. The number of untreated carious cavities and poor hygienic condition of the oral cavity directly affects the severity of candidiasis. Acute forms of candidiasis were observed mainly in patients with high DMF and PMA indices. The severity of candidiasis depends on the degree and duration of wearing dentures and hygienic conditions - the most severe forms of invasive candidiasis were observed in the presence of removable plate prostheses, the complete absence of teeth, and the use of a prosthesis for more than 10-15 years. A combined lesion of the oral mucosa and the red border of the lips was observed mainly in patients older than 60 years. Conclusions: The presence of candidiasis in the oral cavity in patients with removable plate prostheses leads to a statistically significant change in the indicators of local immunity of the oral cavity: an increase in the concentration of serum IgG and IgA and the values of the coefficient of the balance of local immunity factors.