Standardization of sterilization regimes for textile materials under pandemic conditions (COVID-19) by the method of ionizing radiation

Methods for sterilizing textile materials in a pandemic (COVID-19) and the disadvantages of these methods are presented. A number of modern scientific works related to the sterilization of textile materials in a pandemic are considered, aimed at developing a technology for sterilizing protective medical masks and medical suits by radiation methods using gamma radiation. As a result of the analysis, it was found that the use of gamma radiation is a very dangerous technological process since natural sources are used - gamma rays, radiation technologies with gamma radiation are difficult when disposing of spent energy sources and are not easy to maintain. For sterilization of textile materials, the method of ionizing radiation is proposed. The essence of the method is that the textile material is sterilized by accelerated electrons. The expediency of carrying out theoretical and experimental research has been determined. It was found that the main criterion for sterilization of textile materials is the absorbed dose. The absorbed dose is determined experimentally, but such a procedure is time-consuming and resource-intensive, and it is not always possible to carry it out. Therefore, to calculate the absorbed dose, it is proposed to apply the mathematical formula of the absorbed dose of medical textile materials, depending on the frequency of passage of pulses of the accelerated electron beam, conveyor speed and geometric parameters of textile materials, the mathematical formula will allow finding the optimal technological modes of the sterilization process. Using the mathematical model of the absorbed dose of radiation by the material with the proposed technology, taking into account the properties of materials, it is possible to calculate the modes of irradiation of various textile materials that differ in size, shape, and physical properties, which will make it possible to develop a system of normative modes for the technology of radiation-physical sterilization and to ensure the legislative and regulatory requirements of hygiene in conditions of a pandemic.

Computing Bounds for General Randic Coindex of Sum Graphs

The physical and structural properties of molecular structure or graph such as boiling point, melting point, surface tension, or solubility are studied using topological index (TI). Topological index is a mathematical formula that can be applied to any graph which models some molecular structures. The various operations play an important role in graph theory such as joining, union, intersection, products, and subdivision. In this paper, we computed the bounds for general Randic coindex of F -sum graphs such as ( S -sum, R -sum, Q -sum, and T -sum) in the form of their factor graphs. At the end, results are illustrated by numerical table for the particular F -sum graphs.

Measuring refractive index gradient of sugar solution

To measure refractive index at a particular altitude in a solution with vertical refractive index gradient, a transparent wedge-shaped container was constructed altogether with the development of mathematical formula derived from the Snell’s law. The refractive index of the solution can be calculated by measuring the angles of incoming and outgoing laser beams relative to respective normal line. By varying height of the laser beam, the refractive index as a function of height of a sugar solution was obtained. This technique is applied to investigate Fata Morgana which is a kind of superior mirage resulting from bending of light in a medium with density gradient.

Novel Optimal Perennial Calendar Systems vs Gregorian Calendar and Their Impact on the Energy Demand and the Environment

Have you ever missed an event because you were confused about days and dates? Do you remember the date of any specific day without looking at the calendar? Is the current Gregorian Calendar efficient enough for usage, and does it facilitate our life or make it more complicated? Have you ever thought about a simpler way to calculate days and dates in a year without using a calendar? All these questions are answered in this paper, in which authors propose two contributions, (a) a new mathematical formula that calculates the number of days in any month in the Gregorian calendar for any year, including the leap years, (b) an original optimization method that creates optimal perennial calendars. Results show that there is more than one way to create a perennial calendar using the proposed optimization model, in which the number of days in each month does not change, neither the dates. Hence, all months have the same sequence of days and dates. In other meaning, Monday becomes the first day of every month, and Sunday becomes the last day. Consequently, the calendars become much easier to memorize, and it becomes simpler to predict the days and dates in any year. In addition, the proposed optimal perennial calendar system reduces the energy demand and pollution worldwide, in which it has less impact on the environment and climate change compared to the Gregorian calendar. This is due to the fact that less printed-out calendars are produced, and less time is spent on the digital calendars to check the dates and days.

C-graphs - A Mixed Graphical Representation of Groups

Corresponding to each group Γ, a mixed graph G = (Γ,E,E′) called C-graph is assigned, such that the vertex set of G is the group itself. Two types of adjacency relations, that is, one way and two way communication is defined for vertices, to get a clear idea of the underlying group structure. An effort to answer the question, ‘Is there any relation between the order of an element in the group and degrees of the corresponding vertex in the C-graph’, by proposing a mathematical formula connecting them is made. Established an upper bound for the total number of edges in a C-graph G. For a vertex z in G, the concept Connector Edge CEz is defined, which convey some structural properties of the group Γ. The Connector Edge Set is defined for both a vertex z and the whole C-graph G, and is denoted as C E z and C E G respectively. Proposed the result, C E G = E if and only if |Γ| = 2n, n ∈ N. Finally, the properties of G, which the Connector Edge Set C E G carry out are discussed.

Mathematical Principle Analysis of Separation Point Prediction

During the development of fluid mechanics, fluid separation is an important issue. So far, there is no mathematical formula to reveal and describe the essence of fluid separation. At the same time, due to the high cost and limitation of the experimental method, another method is urgently needed to predict the separation position of the fluid. After axiomatizing fluid mechanics and combining the principle of excited state of quantum mechanics, this paper reveals that fluid separation is a special form of fluid in an excited state, and deduces the state conditions of fluid separation. The research results of this paper provide new ideas for solving problems in fluid separation and engineering applications.