Numerical simulation of water and water emulsion droplets evaporation in flames with different temperatures

The models of heat and mass transfer and phase transition for “water droplet – flame” system have been developed using non-stationary nonlinear partial differential equations. The system of differential equations was solved by the finite-difference method. The locally one-dimensional method was used to solve the difference analogous of differential equations. One-dimensional differential equations were solved using an implicit four-point difference scheme. Nonlinear equations were solved by the iteration method. The evaporation rates of water droplets (with sizes from 0.05 mm to 5 mm) in the flame zone (at the temperatures from 500 K to 1200 K) were determined. Theoretical analysis established essentially nonlinear (close to exponential) form of dependence of the water droplet evaporation rate on the temperature of the external gas area and the temperature of a droplet surface. In particular, the water droplet evaporation rate varies from 0.25 to 0.29 kg/(m2s), when the temperature of external gas area is about 1100 K. On the other hand, the water droplet evaporation rate does not exceed 0.01 kg/(m2s) when the temperature of external gas area is about 350 K. Besides, it has been found out that droplets warm up at different rates depending on their initial temperature and velocity. As a result, the integral characteristics of droplet evaporation can increase substantially, when droplets move through the external gas area at the same temperature. We performed a similar investigation or droplet streams with droplet concentration 0.001–0.005 m3 in 1 m3 of gas area (typical parameters for modern spray extinguishing systems)

Characteristics of adverse side effects of corticosteroid therapy in children with nephrotic syndrome and methods of pharmacological correction

The article discusses the issues of the long-term glucocorticosteroid therapy in children with nephrotic syndrome that results in severe adverse side effect

New methods to detect early manifestations of adverse side effects of glucocorticosteroids in children

The article focuses on the early manifestations of adverse side effects in children with nephrotic syndrome receiving glucocorticosteroids. The search for criteria of early side effect manifestations is a real challenge nowadays. The authors developed new diagnostic criteria for early detection of pharmacotherapeutical side effects in children with nephrotic syndrom

FORMALIZATION OF THE PROBLEM OF THE SDN NETWORK PARTITIONING INTO ROUTING ZONES

On of the key goals that should be solved to efficiently organize network routing is splitting the network to, in some sense, optimal set of routing zones. The work considers generalized mathematical formalization of the graph partition problem. Graph defines SDN network topology. According to this topology possible objective functions and constraints were formulated. Objective functions take into account cut parameters, subgraphs and\or cuts boundary vertices characteristics. Constraints take into account weights and probabilities .Key words: software-defined networking, routing zones, graph partition, graph cut, total cut weightкандидат технічних наук, Коган А. В., доктор технічних наук, професор, Кулаков Ю. О., кандидат технічних наук, Сперкач М. О., кандидат технічних наук, доцент, Жданова О. Г. Формалізація задачі розбиття мережі SDN на зони маршрутизації / Національний технічний університет України “Київський політехнічний інститут імені Ігоря Сікорського”, Україна, Київ Однією з ключових задач, що повинні бути розв’язані для організації ефективної маршрутизації в мережах, є розбиття всієї мережі на оптимальну в деякому сенсі кількість зон маршрутизації. В роботі розглядається узагальнена математична формалізація задачі розбиття графу, який описує фізичну топологію мережі SDN. Відповідно цієї топології були сформульовані можливі цільові функції та визначені обмеження задач розбиття графу. Цільові функції враховують параметри розрізів, підграфів та/або характеристики граничних вершин розбиття. Обмеження враховують ваги та ймовірності виключення/виходу з ладу вершин і ребер.Ключові слова: програмно-конфігурована мережа, зони маршрутизації, граф, розбиття графу, розріз графу, гранична вершина, сумарна вага розрізу

A planar source of atmospheric-pressure plasma jet

In a single-barrier discharge with voltage sharpening and low gas consumption (up to 1 L/min), plane atmospheric pressure plasma jets with a width of up to 3 cm and length of up to 4 cm in air are formed in the slit geometry of the discharge zone. The energy, temperature, and spectral characteristics of the obtained jets have been measured. The radiation spectrum contains intense maxima corresponding to vibrational transitions of the second positive system of molecular nitrogen N2 (C3Π u → B3Π g ) and comparatively weak transition lines of the first positive system of the N 2 + ion (B2Σ u + → X2Σ g ). By an example of inactivation of the Staphylococcus aureus culture (strain ATCC 209), it is shown that plasma is a source of chemically active particles providing the inactivation of microorganisms

Risk Factors for Obesity Development in Different Periods of Childhood

Obesity is an important health problem in many countries. Obesity among the child population is growing steadily, including the Russian Federation. Development of this disease often occurs in childhood and sometimes the origin of obesity goes back to prenatal period. There are a number of endogenous and exogenous factors than play an important role in development of obesity. These are heredity, socioeconomic status of the family, factors which are revealed during pregnancy and child delivery — weight gain, administration of antibacterial drugs and hyperglycemia in mother during her pregnancy, mode of delivery, feeding type and time of complementary food introduction, excessive consumption of calories with food, improper daily routine and lack of sleep, skipping meals, use of gadgets and associated physical inactivity and excessive food intake, marketing of high-calorie foods and others. Prevailing risk factors can be identified for each age period. Study and early identification of risk factors taking into account age of a child is necessary to take timely prevention measures and inform parents and their children about possible reasons and consequences of obesity

Pathogenetic features of acute naphazoline poisoning in children

Acute poisoning by nasal decongestants is an important issue in pediatrics due to physiological and anatomical characteristics of the child’s body and pharmacokinetics of drugs in early childhoo

Morphological and functional characteristics of Trichinella sp. larvae in bears and badgers in the Kirov Region

The purpose of the research is study of morphological and functional characteristics of Trichinella sp. larvae in bears and badgers in the Kirov Region.Materials and methods. The compressor trichinelloscopy (CT) method was used to study 72 sections of muscle tissue samples (in accordance with the Guidelines "Prevention of helminthiasis transmitted through meat and meat products" dated September 23, 1996) from animals obtained during scientific culling. The sections were prepared from the diaphragmatic peduncle muscles and the diaphragm of bears and badgers along the muscle fibers, and placed in the compressorium. The sections were then transferred to glass slides, and provisional slides were prepared and examined using various magnifications (× 8, × 20, × 40). Morphometric measurements were performed using a microscope at × 40 magnification, then the capsule index was calculated. Digestion (peptolysis) in artificial gastric juice was performed according to the P. A. Vladimirova’s method modified by A. V. Uspensky and F. Skvortsova after the test samples were placed in various temperature conditions from 5 to -18 °C, and the parameters of both animal species were compared. The viability of Trichinella sp. larvae was evaluated in a Petri dish in saline at a room temperature. Morphological changes were recorded in the larvae structure (coiled larvae against the total number of isolated, coiled and stretched larvae) and their mobility.Results and discussion. We studied badgers and bears infected by Trichinella spiralis larvae in the Kirov Region. The Trichinella sp. larvae were found in all examined sections of the infected animals. The infection intensity was higher in the badger than the bear and amounted to 218±79.5 larvae per 1 g of muscle, while it was 115±28.5 in the bear. The stated above is explained by the fact that the badger eats carrion more often, and typically visits spontaneous dumps. For postmortem diagnosis of trichinellosis in the obtained bears and badgers, we can use trichinelloscopy and peptolysis methods which are aimed at detecting infection sources and preventing zoonosis in humans