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Бюллетень науки и практики @bulletennauki
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Все статьи: 7297
Study on heat transfer performance of non-integral capillary core sintered uniform plate
Статья научная
This paper mainly introduces the sintering process of the monolithic capillary wick and analyzes the influence of different copper powder particle size, filling rate, copper powder shape and heat source size on the heat transfer performance of the isothermal plate. The experimental results show that: (1) For the isothermal plate sintered with spherical copper powder, the capillary force of large particle size copper powder is small, but the flow resistance is also small, and the performance of the isothermal plate sintered with large particle size copper powder is better. (2) In the case of low filling rate, the isothermal plate is dried due to insufficient return fluid. In the case of high filling rate, on the one hand, the thickness of the liquid film at the evaporation end of the isothermal plate is large, resulting in additional thermal resistance. On the other hand, the thin film evaporation mode will be transformed into pool boiling mode, which will reduce the heat transfer performance. (3) Spherical copper powder sintered plate with regular shape has the best performance, while dendritic copper powder sintered plate has relatively high thermal resistance. (4) The heat source area has a great influence on the thermal resistance of the plate. Under the same heating power, the thermal resistance of the small area heat source is much higher than that of the large area heat source; The thermal resistance of sintered copper plate is lower than that of pure copper plate under two heat source areas.
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Study on the effect of diaphragm booster on the pulsed heat transfer of cooling system
Статья научная
This paper has developed a diesel engine cylinder liner and cooling water heat exchange enhancement device, including diesel engine cylinder liner, cylinder liner water cooler, hydraulic accumulator, check valve, diaphragm booster, centrifugal water pump, pulse valve and Conical tube. As well as the pulsating circulation system and booster system composed of equipment. The device heats the heat generated by the diesel engine cylinder liner in a pulsating circulation system through a cylinder circulator in a pulsating circulation system to exchange heat with the external low-temperature seawater. By controlling the opening and closing of the pulsating valve in the pulsating circulation system, fluid is generated in the pipe. Pulsing and hydraulically impacting the diaphragm booster connected near the pulsation valve pipeline, the fluid at the outlet of the diaphragm booster is subjected to hydraulic shock and circulates in a closed booster circuit connected to the diaphragm booster and passes through the cone during the flow...
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Studying Students' Models of Formation of Gender Culture in Higher Education Institutions
Статья научная
In this article, it is important to improve the pedagogical environment in higher education institutions, and to create a gender culture among students. For this, it is necessary to implement gender culture in the higher education system and develop effective mechanisms for its management. It is urgent to consider the problems of forming the gender culture of students and implement measures to shape it into a system of training future specialists. The changes taking place in modern society determine the rapidly developing culture and determine the need to improve the educational process using everything that develops advanced thinking, moral and behavioral models in students. Gender culture of students is characterized by the understanding of the concept of gender, the essence and importance of gender characteristics in the life of society, a positive personal attitude towards oneself and the society in general as a carrier of certain gender characteristics.
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Краткое сообщение
Hydronephrosis refers to diseases of the urinary system, which are characterized by high prevalence. Moreover, this pathology of all obstructive uropathies, leading to a decrease in the function of the renal parenchyma, accounts for up to 15% of cases. Therefore, the search for various markers involved in the development and progression of kidney damage is particularly relevant, since in the literature there are very contradictory data. Our article presents the results of a survey of 40 patients with established and confirmed diagnosis of stage I hydronephrosis (according to the classification of N. A. Lopatkin), and 20 completely healthy people (control group). All patients initially and at the end of the study determined the levels of cytokines: IL-1a, IL-1b, IL-1ra and G-CSF. We found that patients with hydronephrosis had higher rates of pro-inflammatory components of the IL-1β system: IL-1β - 104.42 (75% CI [111.8-151.4]) pg/ml, which was significantly higher than in the control group 3.7 times...
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Studying the Effect of Fungicides in Field Conditions on Disease of Fruits of Tomatoes
Статья научная
Tomato is one of the most important food crops. In recent years, tomatoes have been found to be susceptible to various diseases that damage the crop. One of these diseases is black mold of tomato fruits (alternariosis). Leaves, stems and fruits of the plant are damaged. Dark brown or black lesions develop on tomato fruits. The resulting tissue damage is more common where the fruit is attached to the twig.
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Studying the condition of irrigated land in the Mil-Mughan economic region
Статья научная
The article examines the current reclamation state of irrigated lands in the Mil-Mughan economic region. There are favorable conditions for irrigation and growing heat-loving crops. However, the development of irrigated agriculture here is limited by soil salinity, which is widespread in the study area over quite large areas. Thick layers of soil and groundwater are susceptible to salinization. Conventionally, the territory is suitable for irrigation in hydrogeological and reclamation terms.
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Studying the condition of irrigated land in the Mil-Mughan economic region
Статья научная
The article examines the current reclamation state of irrigated lands in the Mil-Mughan economic region. There are favorable conditions for irrigation and growing heat-loving crops. However, the development of irrigated agriculture here is limited by soil salinity, which is widespread in the study area over quite large areas. Thick layers of soil and groundwater are susceptible to salinization. Conventionally, the territory is suitable for irrigation in hydrogeological and reclamation terms.
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Stylistic devices commonly used in English riddles
Статья научная
True riddles consist of two parts, one functioning as a question, the other as an answer. In riddling the answerer or riddle tries to find an acceptable answer to the question. Sometimes riddles are deliberately misled because the “right” answer is completely unexpected. The article includes the definition of riddles, types of riddles and analysis of stylistic devices used in English riddles. Stylistic devices make our speeches more interesting and livelier and help us to get and keep our reader’s and listener’s attention. Stylistic devices often provide emphasis, freshness of expression, or clarity. In the article it is clarified three main levels of stylistic devices: phonetic, lexical and syntactical stylistic devices commonly used in English riddles.
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Stylistic peculiarities of sport commentation
Статья научная
In this article the light is thrown to different stylistic devices that can be found in such genre as sport commentary. A special attention is paid to such stylistic devices as metaphor, metonymy, charactonyms, and simile that can be found in the speech of any football commentator and with a help of which commentator colors his speech and gives a possibility of the real presence to a viewer. Nowadays sport represents a very significant part of our life and with the help of mass media development sport acquires greater importance in our society. One can call football to be the famous and very popular kind of sport among people of all ages. A large number of football fans switch on their TV sets when their favorite football command emerges in a field. And there football commentator helps to establish intercourse between a viewer and sport event. During the match commentator explains in details all the events that take place in a field. A commentator gives a full picture of the football game and at the same time he entertains the viewers to keep their interest to the game. It is not easy as it may seem at first, as a commentator should possess rich vocabulary, and be a very intelligent and well-informed person not only to comment actions of football players but also to fill the pauses during the plain game.
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Subalpine grassland vegetation of Yardimli and Astara districts (Azerbaijan)
Статья научная
Subalpine grasslands of Talish highlands are common in the subalpine zone of Yardimli and Astara highlands at lawny mountain-meadow soils at the height of 1750 m to 2400 m above sea level. During the carried out ecological-geobotanical research, it has been determined 3 formation classes, 5 formation groups and 11 associations. In parallel with the study of type composition and structure of phytocenosis found in the area of investigation, it has been also determined endemic species, productivity of formations, and intensification of degradation at soil-plant coverage of some lawny subalpine grasslands, decrease in abundance and productivity of forage crop. Currently, for the purpose of the improvement of natural phytocenosis productivity, crop quality, protection of their genetic reserve and landscapes, as well as the vegetation study for solution of protection problems on the base of scientific means is of a great importance.
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Subalpine meadow vegetation of Talish highlands of Azerbaijan
Статья научная
Subalpine meadow vegetation of Talish highlands has been spread over the subalpine zone of Lankaran highlands at lawny mountain-meadow soils at the height of 1800 m to 2500 m above sea level. During the carried out ecological-geobotanical research, it has been determined 7 formation classes, 12 formation groups and 20 associations. In parallel with the study of type composition and structure of phytocenosis found in the area of investigation, it has been also determined endemic species, productivity of formations, and intensification of degradation at soil-plant coverage of some lawny subalpine meadows, decrease in abundance and productivity of forage crop. Currently, for the purpose of the improvement of natural phytocenosis productivity, crop quality, protection of their genetic reserve and landscapes, as well as the vegetation study for solution of protection problems on the base of scientific means is of a great importance.
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Sugar beet root-rot illnesses caused by Rhizoctonia: pathogen diversity, pathophysiology
Статья научная
Sugar beet, a biennial root crop, is primarily grown in temperate regions and is increasingly recognized in the biofuel industry as a raw material for ethanol production. It is susceptible to over 20 fungal and 10 bacterial pathogens, which can cause severe damage to the plant and result in significant yield losses, affecting the profitability of growers. One such pathogen is Rhizoctonia spp., a soil-borne fungus that causes root and crown rot diseases and losses during storage periods. Rhizoctonia species live in the soil or on decomposing and drying sections of plants as saprophytes or weak parasites. Factors promoting the disease's development include heavy rainfall, organic-rich soil, heavy soils, high moisture content, temperatures between 35° and 40°C, and a pH of 6.0 to 8.0. Poor drainage systems in the soil also contribute to the development of the disease. Crown rot, first discovered in 1858, is one of the common and devastating diseases that affect sugar beet crops. The causative agent of this disease is Rhizoctonia solani, which can survive under soil for a long time and is particularly severe in heavy soils and soils with inadequate drainage systems.
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Sustainability of introduced Lonicera L. species to Absheron conditions
Статья научная
The study provides a comprehensive analysis of the results of the introduction of 13 species of the genus Lonicera L. in the conditions of Absheron. Information was obtained on the developmental biology of the introduced species Lonicera L., vegetation features, growth of shoots were studied. The results of many studies of the relationship between winter hardiness and the duration of the growing season are given. It was found that the vegetation can be divided into 6 phenological groups according to the start and end times of the vegetation, and the plants were selected for their sustainability to adverse conditions. The analysis of the collected material shows the distribution of plants by phenogroups and their winter hardiness.
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Sustainable use of agricultural land of Khachmaz district
Статья научная
Land use, like any other natural resource, involves loads on nature and causing harm to it. Therefore, completely harmless production today is considered impossible. Because of this, goals have been identified that establish the rationality of land use. Such goals include, taking into account natural conditions and economic indicators in the corresponding territory, ensuring the interests of society as a whole, the efficiency of the production process, as well as the protection of the quality of land and its reproduction. These goals are always unchanged, and their achievement depends on the technological development of production, the economic level, and the needs of society. In this article, the agricultural suitability level of Khachmaz district land was analyzed based on the cadastral database created on the basis of GIS technologies. It was also noted the need to take a number of measures to reduce the risk of soil erosion.
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Sustainable use of the buffer zone of El Angel ecological reserve, Ecuador
Статья научная
The specifics of management of El Angel Ecological Reserve buffer zone in the Equatorial Andes have been investigated. The main aspects of the environmental impact have been identified. The authors give the recommendations on the sustainable use of the territory to insure employment and lessen the negative impact on the ecosystems such as reducing the use of agricultural chemicals, pasture field planning in accordance with natural environment, firefighting management, control over disboscation and hunting, natural systems monitoring. The creation of a Tourist Center would provide an opportunity to spur economic growth of the region, control and prevent the negative anthropogenic influence.
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Sweeteners in diabetes mellitus diet
Статья научная
According to the statistics submitted by the World Health Organization, sugar consumption has been constantly increasing worldwide. Craving for sugary foods is a fairly common form of addiction. Poor nutrition, caused by external and internal factors, provokes an increase in the incidence of obesity, arterial hypertension, and diabetes mellitus. This deadly triad annually takes hundreds of thousands of lives across the globe, since the pathologies listed above often go hand in hand, being interconnected. The article discusses the problem of using artificial and natural sweeteners in diet therapy for diabetes mellitus. Nutritionists around the world are concerned about how to preserve the usual sweet taste of dishes and drinks for patients with diabetes, on the one hand, yet avoiding additional harm to their health, and possibly improving the quality of diabetic life, on the other. The author summarized the materials on recent clinical studies on the subject discussed. The article analyses the four sweeteners most commonly used by diabetics: fructose, sorbitol, xylitol and honey stevia ( Stevia rebaudiana Bertoni) leaf powder. Considerable attention is paid to the history of the appearance of each of the substances and medicinal raw materials studied. The author indicates their safe properties and possible disadvantages of use, as well as side effects.
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Symbolism of eyes in songs inspired by mountain landscapes and climate
Статья научная
This article explores the symbolism of eyes in songs inspired by mountain landscapes and climate, focusing on how visual imagery and metaphors related to eyes are used to express cultural perceptions and emotional connections with mountainous environments. By analyzing a selection of songs from various cultures, the study examines the role of eyes as a symbol of perception, observation, and insight, reflecting the influence of the harsh and majestic nature of mountains on human experience and creativity. The research highlights the common themes and unique interpretations of eye symbolism in songs that depict the challenges and beauty of life in mountain regions, offering insights into the interplay between nature, culture, and artistic expression.
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Synergetic modeling of the transportation process in the centers
Статья научная
The functioning of the transport system of the logistics center based on synergetic methods is investigating. The main provisions of synergetic useful for organizing the work of logistics centers are outlining. A model has been built to study the transportation process and the control parameter interval has been found to ensure the stable functioning of the transport network of the logistics center.
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Synthesis and acidity study of Na-ZSM-5 zeolite
Статья научная
Zeolites are a special class of structured aluminosilicates with a developed inner surface and a large number of micropores, which allows them to be used as sorbents, membrane materials, and catalysts. Zeolite ZSM-5 is an aluminosilicate formed by parallel channels with a diameter of 5.3-5.6Å interconnected by sinusoidal channels with a diameter of 5.1-5.5Å. At the same time, the presence of aluminum atoms in the zeolite crystal lattice makes it possible to carry out dehydrogenation, esterification, isomerization, and aromatization reactions, and the presence of microchannels significantly increases the number of collisions of reacting compounds, which leads to a significant increase in the rate of chemical transformations in such systems. The synthesis of ZSM-5 zeolite using structure-directing agents has been known since the late 70s of the last centuries, while the high cost of structure-directing agents used and the long duration of hydrothermal synthesis and the need for subsequent post-synthetic procedures lead to a high cost of the resulting zeolite. One of the possible ways to reduce the cost of the synthesis of ZSM-5 zeolite is the direct use of ZSM-5 zeolite as a structure-forming agent, while the synthesis conditions play a decisive role in the structure of the resulting zeolite. The article presents the results of a study of the synthesis of ZSM-5 zeolite and a study of its acidic properties using locally produced reagents. Zeolite was prepared using pre-milled silica gel, sodium hydroxide, and sodium aluminate. The pre-weighed silica gel sample was filled with sodium hydroxide solution and stirred at 70 °C to form a colloidal solution, after which the pre-prepared sodium aluminate solution was added, and hydrothermal synthesis was carried out at 180 °C for 24 hours. During the synthesis, the Si/Al ratio was varied in the range from 7.5 to 2000, while the resulting acidity ranged from 0.002 to 0.265 mmol(NH3)/g(ZSM-5). It was found that the synthesis of ZSM-5 using pre-prepared reagent solutions is superior to the method using direct dissolution of solid reagents in an autoclave. An increase in the Si/Al ratio from 7.5 to 100 leads to a corresponding increase in surface acidity from 0.066 mmol(NH3)/g(ZSM-5) to 0.265 mmol(NH3)/g(ZSM-5). A further increase in the Si/Al ratio to 2000 leads to a decrease in surface acidity to 0.002-0.005 mmol(NH3)/g(ZSM-5). A reliable and simple method for the synthesis of ZSM-5 zeolite has been developed, providing a zeolite yield of up to 97%.
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Synthesis and acidity study of mixed MFI-mord type zeolite
Статья научная
Zeolites of various nature are widely used in the chemical industry, the fuel and energy sector of the economy as sorbents, catalysts and materials for the creation of inorganic membranes for various purposes. At the same time, it is possible to change the acid properties of the surface of zeolites both by varying the ratio of silicon to aluminum or silicon to phosphorus, and by joint synthesis of zeolites of various types with different acidic properties. The presented article provides a method for the sequential production of a zeolite of a mixed structure type MFI and mordenite. Synthesis of the original MFI type zeolite was carried out using seed grains by the hydrothermal method for 72 hours, followed by washing and drying of the zeolite. To obtain a layer of mordenite on the surface of the MFI type zeolite, the initial zeolite was pretreated with alkali and then treated with n-butylamine. In this way, nine samples of zeolite with different acidic surface properties were obtained. Determination of the acidic properties of the surface was carried out by the method of ammonia chemisorption followed by its desorption from the surface of the zeolite. For this purpose, the test sample was loaded into a quartz cuvette, purged with argon at a temperature of 800°С, after which the temperature dropped to 150°С, and the surface of the zeolite was treated with ammonia. Subsequently, the test sample was heated up to 800°С with registration of desorption curves. The amount of adsorbed ammonia was carried out according to previously prepared calibration curves. The synthesized samples of zeolites had different acidity from 0.48 to 0.72 mmol(NH3)/g(sample). In this case, the total acidity of the samples correlated with the ratio of silicon to aluminum in the zeolite samples. Also, depending on the ratio of the MFI and mordenite structures in the zeolite sample, it is possible to vary not only the number, but also the strength of the formed acid sites. So, an increase in the content of mordenite contributes to an increase in the strength of acid centers. The developed method for the synthesis of mixed structure zeolites of the MFI type mordenite made it possible to control the surface acidity of the synthesized samples.
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