Numerical simulation of nitrogen oxide formation in dust furnaces

Even though natural sources of air pollution account for over 50 % of sulphur compounds, 93 % of nitrogen oxide which are the most dangerous artificial anthropogenic sources of air pollution and primarily associated with the combustion of fossil fuel. Coal-fired thermal power plants and industrial fuel-burning plants that emit large quantities of nitrogen oxides (NО and NО2), solids (ash, dust, soot), as well as carbon oxides, aldehydes, organic acids into the atmosphere pollute the environment in majority. In the present work, a mathematical model and a scheme for calculating the formation of nitrogen oxide has been developed. Also, the dependence of the rate of release of fuel nitrogen from coal particles at the initial stage of gasification and content of volatiles has been obtained. The main regularities of the formation of NOx at the initial section of the flame in the ignition zone of the swirl burner flame during the combustion of Ekibastuz coal have been revealed. Modern environmental requirements for the modernization of existing and the creation of new heat and power facilities determine the exceptional relevance of the development of effective methods and constructions to reduce emissions of nitrogen oxides, sulfur oxides and ash to 200, 300, and 100 mg/nm3 at a=1.4. The dust consumption in all experiments was kept constant and amounted to 0.042 g/s, as well as with the results of calculating the thermal decomposition of the Ekibastuz coal dust, the recombination of atomic nitrogen into nitrogen molecules, and the kinetics of the formation of fuel nitric oxide. It was found that despite the presence of oxygen in Ekibastuz coal for gases Odaf=11.8 % in an inert atmosphere, nitrogen oxides are not formed

INTENSIFICATION AND STUDY OF HEAT TRANSFER AND FRICTION IN THE PLATE HEATING SURFACES OF THE KMS-2 AIR HEATER WITH A PRESSURE GRADIENT

A numerical study of heat transfer and friction in the heat exchanger channels in the presence of a variable pressure gradient is performed. The research was carried out in software complexes (Code_Saturne, Salome). The results of the validation of the research method are presented and they showed that the deviation of the numerical simulation results from the calculation data according to the known criterion equations is within the error of generalization of the experimental data by the criterion equations. According to the results of studies at Red=3000, Red=4177, Red=6000, it was found that the average value of the heat transfer coeffi cient of the channel of variable cross-section is up to 20 % higher than for the channel at dp/dx0. At the same time, the thermal-hydraulic effi ciency of the alternating channel (L=117 mm, l=58.5 mm, n=2) in the initial section at x =0...0.08 is lower than in the channel with dp/dx>0 by 26.7 %, and at x =0.08...1 it is higher by 5 ... 15 %, at dp/dx

12. The Big Question: World Order or World Chaos?

This final chapter addresses a really big question: are international relations heading towards order or chaos? To answer this question, it interrogates the different IR theories presented in previous chapters. An initial section provides a conceptual map, based on a review of different understandings of the concept of world order. The chapter proceeds by discussing the effect of the rise of authoritarian power such as China, new challenges in established democracies, fragile states in the Global South, and the governance provided by international institutions. The chapter ends by arguing that the glass is at the same time half-full and half-empty: the world faces new and formidable challenges and we are very far from meeting current aspirations for world order; at the same time, global relations are much more ordered than they used to be just a few generations ago—and things are far better than many pessimists claim.

Comunicación epistolar y colaboración científica entre especialistas alemanes en Sudamérica a fines del siglo XIX. Un estudio de la correspondencia entre Rodolfo Lenz y Robert Lehmann-Nitsche

The following paper undertakes the presentation and subsequent analysis of the initial section of an extended, although only partially preserved letter exchange between two salient German scholars settled in Argentina and Chile from the end of the 19th century on, and during the first decades of the 20th century: Rudolf Lenz, trained in linguistics and Romance languages at the renowned Romanistik School of Bonn, who worked at the Instituto Pedagógico in Santiago de Chile, and Robert Lehmann-Nitsche, a Prussian physician and anthropologist who was in charge of the Anthropological Section of a brand new modern Museum in Argentina’s recently founded city of La Plata. The letter exchange between them lasted from 1897 until 1928 and the analysis of its initial pieces (1897–1898) allows us to see how personal and scientific networks were constructed, and how German science and sociability managed to settle down in such distant locations and still remain connected with its system of origin.

BECOMING OF THE DEPARTMENT OF HUMAN ANATOMY AT POLTAVA STATE MEDICAL UNIVERSITY SINCE ITS FOUNDATION AND ITS MAJOR ACHIEVEMENTS

In its becoming, Poltava State Medical University has passed a thorny path from the odontology faculty, created on the basis of the Kharkov Medical Academy in 1921, to the leading specialized institution for training medical and healthcare professionals. In 2021 the university has celebrated its 100th anniversary. In 1950, the Department of Human Anatomy moved to a new location and dedicated to the training of medical professionals, research activities. The scope of scientific research conducted at the department covered issues on the structure of glands of the mucous membranes, lymphoid tissue of the initial section of the digestive system, structural peculiarities of autonomic nervous system. The department put a lot of effort to equip microscopic, histological, histochemical and photo laboratories, to create the museum of the department. Scientists developed and manufactured various devices and techniques for conducting morphological studies, which made it possible to publish numerous methodological recommendations, textbooks, and to conduct research for the candidate and doctor degrees. The anatomical museum, refurbished and modernized in 2005 and known even abroad is the subject of honour not only for the department, but for the University as well. The museum is also a matter of utmost interest to young visitors during the Open Days, students from other universities. The Department of Human Anatomy seeks to capitalize on a number of pedagogical experiences and research achievements to transfer knowledge and know-how to young generation of students and scientists.

Intensification of heat transfer in the inlet of the convective stage of the recuperative-burner unit

The study of aerodynamics and heat transfer in the recuperator convective stage of the recuperative-burner unit with the jet leakage of the flue gas flow onto the outer cylindrical surface is carried out. Numerical modeling of the problem was carried out in a three-dimensional formulation using the ANSYS Fluent software package. It was found that in the original design of the recuperative-burner unit, there is a significant unevenness of heat transfer along the length and perimeter of the working surface of the convective stage. In the initial section of the annular gap, a stagnant zone with the lowest heat transfer rate is observed. To eliminate the stagnant zone and to intensify heat transfer on the surface in this area, it is proposed to make the entrance to the perforated pipe in the form of an inner quarter of a torus; to install smooth protrusions on its surface; to locate an annular flow divider on the inner surface of the heat transfer wall, which separates the front part of the annular channel with formation of a set of vortex chambers. The research results are presented.

Bronchial Glands: Age, Regional and Individual Structural Features

The aim was to study the quantitative indicators and structure of the distribution of the glands in human main bronchi in the age aspect.Material and methods. The object of the study was the glands in the walls of the main bronchi, obtained as a single complex together with the lower part of the trachea, including the area of bifurcation. Samples were taken from 110 corpses of people in the age range from the neonatal period to 87 years (10 observations in each age group), who died from causes not related to the pathology of the respiratory system and did not have pathological changes in the respiratory system at autopsy. For micro-macroscopy using an MBS-9 binocular microscope, the glands in the walls of the main bronchi were selectively stained with methylene blue according to R.D. Sinelnikov, followed by fixation in a saturated solution of ammonium picric acid. The following characteristics were analyzed: the shape of the glands, their total number on the total preparation, the density of their location (the number of the mouths of the excretory ducts per 1 cm2), the width of their initial section. Due to the normal distribution of the data, the methods of parametric statistics based on the Statistica 6.0 program were used for statistical data processing. Statistical data processing included the calculation of the arithmetic mean indicators, their errors, the analysis of the amplitude of the variation series of each indicator was carried out.Results. The performed macro-microscopic examination revealed an asymmetry in the distribution of glands – the number and density of distribution of glands was 1.50–2.10 times higher (p <0.05) for the left bronchus than for the right and 1.56–2.91 (p <0.05) times more in the cartilaginous than in the membranous part. At the same time, the width of the orifice of the gland showed opposite patterns. In terms of age, there was an increase in the number of glands and their size with a maximum by the age of 21–35 and a subsequent decrease by senil age. The distribution density decreased throughout the entire period of life.Conclusion. The revealed age, regional and individual features of the structure of the glandular apparatus of the main human bronchi may be of interest both in scientific research and in clinical practice, forming a basic description of the structural norm.

Safe Mining Assessment of Artisanal Barite Mining Activities in Nigeria

Barite, used in mud formulation, is mined in several places to support the industry. However, there is insufficient literature on the downside of mining and associated hazards, especially in the artisanal barite mining sector. This paper contains three parts. The initial section reviews major causes of mining accidents and health hazards in Nigeria. The second section examines existing but weak institutional frameworks and policies for artisanal and small-scale mining (ASM) in Nigeria. In the third part, data from questionnaires and heavy metal contamination assessment are compared with health and environmental standards to identify and characterize hazards. It was observed that 54% had health challenges traceable to illicit drugs, and 54% were ignorant about the use of safety kits. The UV-Vis, AAS, and ICP-MS analyses confirmed lead, barium, zinc, copper, and iron in the water samples. Index of geoaccumulation (Igeo) and contamination factor (CF) show that water samples are moderate to highly polluted by Pb2+, Ba2+, and highly contaminated. The chronic daily intake assessment and health quotient analysis revealed that the accumulation of lead and barium is possible and can initiate chronic diseases in humans over a long time. Certain safe mining protocols and controls are recommended.

The method Foucault gave us: the Foucauldian toolbox for thinking about philosophical problems in a digital context. Some notes and examples from the 2019 Chilean mobilizations

This paper seeks to highlight the French philosopher Michel Foucault's contributions regarding his analysis of power. In this sense, the text proposes a conceptual transition around the ideas that could have interested the author within a digital context, integrating some notes and examples from the 2019 Chilean mobilizations.The article has an initial section that exposes genealogy as a way of approaching social reality. Then, it shows the social behaviors anticipation possibilities and their relationship with the information available on the web. Later, it renders an account of the algorithmic governmentality notion as a key to reading it in both normative structure and a political possibility to final state reflections.

संशयादिपदार्थविश्लेषणम् [Samshayadipadarthavishleshanam]

न्यायदर्श नस्य प्रतिपादको महर्षि गौतमो ऽस्ति । न्यायदर्शने विशेषतो ग्रन्थकारेण निःश्रे यसप्राप्तिमार्ग प्रदर्शितो विद्यत । न्यायदर्श नानुसारं पदार्थानां तत्त्वज्ञान नै व मा क्षप्राप्तिर्भ वति । प्रमाणादिषा डशपदार्था नां तत्त्वज्ञानं यथार्थ ज्ञानं वामा क्षस्य मूलमार्गा विद्यते । अतो यमाले खः पदार्थानां मध्ये संशयादिपदार्था नां प्रमाणप्रमे याभ्यां पृथगुपदेशः कारणत्वप्रतिपादने , एतेषां लक्षणविश्ले षणेचकेन्द्रितो विद्यते । अस्मिन्नालेखे सर्व प्रथमं न्यायाभिमतप्रमाणप्रमे ययो स्वरूपनिदर्श नपूर्व कं संशयादिपदार्थ स्वरूपविश्ले षणं क्रियते । प्रमाकरणरूपाणां प्रमाणानां सहयो गितया तदङ्गरूपे ण संशयादिपदार्था नामप्यन्तरभावस्य कर्तु शक्यत्वात् , अथवा प्रमायाः विषयबो धेषुप्रमे येषु मध्ये सर्व मपिसंशयादिपदार्थ जातमन्तर्भू तं भवत्यवेति, कुतः पृ थक्तया सूत्रकारेणो द्दे शः कृ तः ? इति समस्यायाः समाधानार्थ मयं प्रयत्नो वर्तते । सकारणसंशयादिपदार्थो पदे शप्रतिपादने न एतेषां स्वरूपस्य सम्यक्तया विश्लेषणमत्र विहितमस्ति । अन्तचैतेषां प्रमाणप्रमे यादिभ्यः पृथुगुपद्दे शस्य कारणत्वं प्रदश्र्य निष्कर्ष : प्रदत्तो विद्यते । अस्मान्निकर्षा न्न्यायनिर्दि ष्टानां षो डशपदार्था नामध्ययनाध्यापनाय सारल्यं भविते त्यपे क्षते । [The term NyayaDarshan was first introduced by MaharshiGautam. The philosophy NyayaDarshan especially mentions the way to achieve Moksha. The philosophy categorizes each physical and non-physical element in 16 categories known as “Padartha”. According to NyayaDarshan, having the knowledge and perceiving these Padartha in their own original form, is the only way to achieve Moksha. This paper tries to investigate the reasons for separately discussing and defining 14 Padartha other than Praman and Prameya known as Smshayadi in Nyaya Sutra. In the initial section, the brief discussion on Praman and Prameya followed by SamshayadiPadartha of NayaDarshan has been mentioned. Praman being a medium of Prama and Samshayadi being a supportive concept of Praman; as a result Smashayadi itself can be included within Praman. Additionally, as all Smashayadi are Prameya or the subjects of Prama, Smashayadi also can be included within Prameya. We have theoretical evidence that Samshayadipadartha can be included either in Praman or Prameya. Hence, this paper attempts to investigate the question, “Why does Naya Darshan mention the Samshayadi Padartha separately?” The in-depth dialog and reasons for including Samshayadipadartha within the Nyaya Sutra has also been discussed. Article includes the reasons for separating these Padartha from Praman and Prameya and concludes with the expectation of understanding 16 padartha easily for simplifying the teaching-learning process.]