Mathematical description of matter exchange between water components and adsorbing surface of filter medium of water purification units

The article presents the theory of mass transfer processes between water polluting components and the adsorbing surface of filter medium of water purification units

MONITORING SYSTEM FOR UNDER-WATER PIPE LINE

The growing interest in new under-water pipe lines for the delivery of natural gas (in Baltic Sea, Mediterranean region, Caspian Sea, Black Sea, etc.) needs a new instruments for the monitoring of leakage and/or possible destruction of the pipes, which could not only disturb fragile ecological systems of Baltic and other seas, but also can lead to the technological catastrophes. We plan to develop a prototype of the system consisting of pervaporation membrane and gas sensors. Overall system will be immersed into water and will be fabricated in two versions: as a stationary instrument dipped into sea water and as an instrument towed along the pipe line. Micromachined metal oxide semiconductor gas sensors used for the detection of methane concentrations is designed and fabricated using “nano-on-micro” approach. Overall system is optimized from the point of view of minimum power consumption, which is necessary to assure its long term operation under autonomous conditions

Socio-philosophical analysis of the transformation of modern society

The trasformation of the moder society is often considered through the analysys of developing and modernizing countries that are undergoing transitional socio-economic conditions and stages of radical transformation of socio-political structures. At the same time, it is often overlooked that the development of many countries also went through periods of modernization, which included evolutionary and revolutionary transformations. This article will consider different approaches to the socio-philisophical analysis of the modern society transformation with the aim to structure current and historical knowledge of this matter

Black Soldier Fly (Hermetia illucens), a source of antimicrobial peptides

In the modern world, multi-drug antibiotic resistance is an increasingly serious problem which poses a serious threat to both plants, animals and humans. The unreasonable use of antibiotics has led to the spread and increase in the number of infectious diseases that existing antibiotics may not be able to cope with. Thus, there is a need for the development of new classes of antibiotics that do not induce resistance. It is necessary to find agents with new mechanisms of action for the development of such antimicrobial compounds. Antimicrobial peptides are excellent candidates for this role. Penetrating through the membranes, they affect the target protein without high specificity, which in turn reduces the probability of induced resistance to a minimum [13]. Scientists have identified about 57 active peptides belonging to various groups of antimicrobial peptides, including defensins, cecropins, attacins and lysozyme. Defensins form the largest group of antimicrobial peptides in insects. As a rule, a defensin-like peptide contains from 34 to 43 amino acids. Antimicrobial peptides obtained from Hermetia illucens can become a good alternative to antibiotics for the prevention and treatment of infectious diseases, as they differ in their antimicrobial properties and are less likely to induce resistance [8]. The lipid composition as well as the amino acid composition can be changed by different larvae diets. Larvae fat contains oleic, palmitic, lauric, myristic, stearic and palmitolic acids, which are saturated and unsaturated fatty acids, and have an intense effect against bacteria

Spark discharge synthesis of semiconductor nanoparticles for thick-film metal oxide gas sensors

Traditional methods of synthesis of metal-oxide gas sensing materials for semiconductor sensors are based on wet sol-gel processes. However, these processes lead to the formation of hydroxyl groups on the surface of oxide particles being responsible for the strong response of a sensing material to humidity. In this work, we investigated the possibility to synthesize metal-oxide materials with reduced sensitivity to water vapors. Dry synthesis of SnO2 nanoparticles was implemented in the gas phase by spark discharge, which allowed us to produce powder with specific surface area of about 40 m2/g after additional annealing at 610 °C. The drop of sensor resistance does not exceed 20%, when air humidity increases from 40 to 100%, whereas the response to 100 ppm of hydrogen is of a factor of 8 with very short response time of about 1 s

Стробирование радиолокационных отметок при траекторной фильтрации в связанных координатах

Introduction. Modern air targets, particularly drones, are becoming less noticeable, while their manoeuvrability continues to improve. Trajectory processing algorithms have also been improved in order to provide for effective tracking of highly manoeuvring targets. The accuracy of filtering trajectory parameters is largely determined by the reliability of radar information. This has also required an enhanced role for strobe algorithms and the need to increase the effectiveness of strobe radar marks.Aim. To develop and investigate the efficiency of a trajectory strobe algorithm based on the target motion model in a high-speed coordinate system associated with the direction of the target motion and involving the formation of a strobe in the form of a truncated elliptical sector.Materials and methods. The study considered the target motion model in the body-fixed frame. This model was taken as the basis for new trajectory filtering algorithms based on Kalman filtering. Existing methods for strobing radar marks of the target were considered and a new approach based on filtering in the body-fixed frame proposed. The new algorithm assumes the formation of a strobe in the form of a truncated elliptical sector. This form corresponds to the most probable location of the marks of the tracked target. The effectiveness of the proposed solutions is confirmed by the results of mathematical modelling carried out using MATLAB.Results. The study produced analytical expressions for the motion model, recurrent filtering and strobe algorithm in the body-fixed frame. A comparative analysis of tracking effectiveness with the same volumes of the elliptical and proposed strobes was performed. It was established that the algorithm with strobe formation in the shape of a truncated elliptical sector provides for longer target tracking up to the time of the first loss of the mark for speed and highly manoeuvring targets, when compared to the elliptical strobe algorithm. In addition, the average duration of sector strobe tracking does not in practice depend on the initial speed of the target and provides greater accuracy for small measurement error values (less than 50 m) of the coordinates than in comparison with the elliptical one. Conclusion. The described results were achieved by the ability of the strobe in the body-fixed frame to adapt to the direction of motion and target manoeuvring, allowing high-quality target tracking within a larger speed range. Such strobe formation will also reduce the likelihood of skip-ping radar marks from the tracked target and will reduce the number of false marks belonging to other trajectories inside the strobe.Введение. Современные воздушные цели, в особенности беспилотные, становятся менее заметными, а их маневренные возможности продолжают совершенствоваться. Для обеспечения эффективного сопровождения высокоманевренных целей актуализируются и алгоритмы траекторной обработки. Поскольку точность фильтрации траекторных параметров во многом определяется достоверностью радиолокационной информации, возрастает роль алгоритмов стробирования. В связи с этим возникает задача повышения эффективности стробирования радиолокационных отметок.Цель работы. Разработка и исследование эффективности алгоритма траекторного стробирования, основанного на модели движения в скоростной связанной с направлением движения цели системе координат и предполагающего формирование строба в форме усеченного эллипсоидного сектора.Методы и материалы. Рассмотрены модели движения целей в связанных координатах, которые положены в основу новых алгоритмов траекторного сопровождения, базирующихся на калмановской фильтрации. Рассмотрены существующие методы стробирования радиолокационных отметок от цели и предложен новый подход на основе фильтрации в связанных координатах. Новый алгоритм предполагает формирование строба в форме усеченного эллипсоидного сектора. Такая форма соответствует наиболее вероятному местоположению отметок от сопровождаемой цели. Эффективность предложенных решений подтверждается результатами математического моделирования, выполненного в среде MATLAB.Результаты. Приведены аналитические выражения для модели движения, рекуррентной фильтрации и алгоритма стробирования в связанных координатах. Проведен сравнительный анализ эффективности сопровождения при одинаковых размерах эллиптического и предложенного стробов. Установлено, что для скоростных и высокоманевренных целей алгоритм с построением строба в форме усеченного эллипсоидного сектора обеспечивает до 30 % более длительное сопровождение до первой потери отметки от цели, чем алгоритм с эллиптическим стробированием. Кроме того, средняя продолжительность сопровождения для секторного строба практически не зависит от начальной скорости движения цели, а при значениях погрешностей измерения координат менее 50 м имеет большее значение, чем для эллиптического.Заключение. Достигнутый результат обеспечивается способностью строба в связанных координатах подстраиваться под направление движения и маневрирование цели, что позволяет осуществлять качественное сопровождение объектов в большем диапазоне скоростей. Построение такого строба также позволит снизить вероятность пропуска радиолокационных отметок от сопровождаемой цели и обеспечит уменьшение числа ложных отметок и отметок, принадлежащих другим траекториям, внутри строба

Role of Humic Substances in Formation of Safety and Quality of Poultry Meat

The purpose of this chapter was to study the influence of humic substances on the formation of the safety and quality of poultry meat. The high abilities of the natural and organic complex of humic acids “Reasil®HumicHealth” (produced in Russia, Saratov) to sorb and desorb five mycotoxins of compound feed (aflatoxin B1, ochratoxin, toxin T-2, zearalenone and fuminisin B1) were experimentally established. The hepatoprotective ability of humic acids was observed in experiments on broilers using rapeseed meal containing an increased amount of secondary plant metabolites that could cause liver damage. It was found out that the inclusion of humic acids in the amount of 1 and 1.5 g per 1 kg of feed to the main diet of broiler chickens has a more stable positive effect, both in terms of slaughter indicators (yield of semieviscerated carcasses and carcasses of complete evisceration), and in the production of the most valuable natural semi-finished products (breast, chicken legs) due to the intensive growth of muscle tissue. A clear improvement in the morpho-biochemical and immunological parameters of blood and micromorphometric characteristics of the organs of the immune system of poultry was noted with the use of different concentrations of humic acid salts. The use of the additive at the rate of 1 and 1.5 g per 1 kg of feed does not negatively affect the sensory indicators of finished culinary products

Homely social practices, uncanny electricity demands: Class, culture and material dynamics in Pakistan

This research seeks to address the gap in studies of energy consumption in developing countries from a social science perspective. The research uses Social Practice Theory (SPT) to gain better understanding of homeowners’ practices and resulting electricity demand in middle-class households in Pakistan, with broader implications for other developing countries with similar climatic and socio-material contexts. Drawing on the works of Bourdieu (1984, 1997), Schatzki (2011) and Shove and Pantzar (2005), the study aims to unravel the connection between familiar domestic practices and the ‘uncanny’ electricity demand. Material and social constructs of ‘homely’ household practices related to comfort, lighting, cleanliness, cooking and ICT were studied in ten middle-class households in Lahore, Pakistan. The material arrays of the intermittent electricity provision system, modernistic prefigurations of spaces preferred by the middle-class and electrical appliances play an intrinsic role in shaping, and in turn being shaped by, everyday practices. Practices shaped by specific socio-cultural dimensions, such as social acceptance within the neighbourhood community, religious meanings, joint family structures, age disparities and gender segregation. The empirical study aims to further the conceptualisation of socially differentiated practices in domestic socio-material and cultural context of developing countries.The research was part of an on-going PhD sponsored by Cambridge Trus

Tunable optical nanocavity of iron-garnet with a buried metal layer

We report on the fabrication and characterization of a novel magnetophotonic structure designed as iron garnet based magneto-optical nanoresonator cavity constrained by two noble metal mirrors. Since the iron garnet layer requires annealing at high temperatures, the fabrication process can be rather challenging. Special approaches for the protection of metal layers against oxidation and morphological changes along with a special plasma-assisted polishing of the iron garnet layer surface were used to achieve a 10-fold enhancement of the Faraday rotation angle (up to 10.8∘/μm) within a special resonance peak of 12 nm (FWHM) linewidth at a wavelength of 772 nm, in the case of a resonator with two silver mirrors. These structures are promising for tunable nanophotonics applications, in particular, they can be used as magneto-optical (MO) metal-insulator-metal waveguides and modulators