- Все статьи 6181
Статьи журнала - Бюллетень науки и практики
Все статьи: 6181
Статья научная
In the published work, the process of adsorption of organic derivatives of thiourea and dicarboxylic acids (thiourea class) modeled with semi-empirical ZINDO / 1, on iron (97% in steel St3, Poland) is presented. The structures of “thiourea” for the study were chosen so that the sequential complication of the molecular structure could be traced. Such an approach, as will be shown below, reflects with high accuracy the process of protection against corrosion with bacterial content by chemisorption of an organic compound on the metal surface with the formation of a complex compound. In the course of the study, the following compositions were obtained and analyzed: the compositions of the complexes obtained, global and local electro-filter values, a graph showing the dependence of the local electrophilicity of an arbitrary heteroatom taken by the author. The graph shows the equations of the obtained lines.
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Quantum-chemical substantiation of corrosion inhibition of steel with some amino acids
Статья научная
The article describes the process of α-amino acid adsorption on iron of mild steel immersed in 0.01 M H2SO4, this process was modeled using HyperChem 8.0.8 and ZINDO/1. This method reflects the protection against corrosion by chemisorption of α-amino acid on the surface of metal to form a complex adduct, reliably. The compositions of obtained complexes, the energy of boundary orbitals, a graph depicting the dependence of the charge density on the iron atom and the energy of higher occupied molecular orbitals on the anticorrosive protective effect were obtained and analyzed. On the graphs one can see the equations of lines.
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Radiative heat transfer in the furnace space with variable volume
Статья научная
The combustion chamber and flues boiler radiant heat exchange occur between the gas (combustion products) and limiting gas surfaces of the combustion chamber and flues. In this case, part of the energy-emitted gas is absorbed by the surfaces, and part of it is reflected into the gas. The resulting heat flow between the gas and the surface defined by the difference between the amount of energy emitted by the gas on the surface, and the amount of energy absorbed by the gas from the radiation surfaces. The article presents the basic formulas for boilers on solid fuel with movable grate. Calculations show that the change in volume of the furnace leads to a change in radiant heat transfer.
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Radioecological assessment of uranium tails deposits (Sumsar, Shekaftar, Terek-Sai)
Статья научная
The article presents the results of radio ecological studies of the territories of uranium tailings in Kyrgyzstan (Sumsar, Shekaftar and Terek-Sai), as well as their current state and assessment of the radioactive contamination’s potential risks. The ore field of this region is characterized as an extremely complex structure and covers about 30 ore occurrences of lead and rare metals. Starting from the Precambrian period both applicative and disjunctive disturbances within its boundaries have been widely developing and being manifested many times throughout the history of geological development. Oxidized and sulfide ores have been developed within the deposit. Unfortunately, serious miscalculations were made. As result of natural disasters; such as earthquakes, landslides, mudflows, etc., several uranium tailing dumbs have been damaged. Day by day, the risk of destruction and the threat of radioactive contamination of the Kyrgyz Republic territory are increasing. There are eight tailing dumps on the territory of Shekaftar uranium natural-technogenic province, the total volume of which is 1194 thousand m3 of radioactive waste. There are 15 mountain dumps of substandard ore with an ore volume of 4585.6 thousand m3 hour, in local areas it exceeds 500 μR/h.
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Rare endangered species of the Rosaceae family of the Rosa L. genus in the flora of Azerbaijan
Статья научная
The study examined the distribution areas, status, biological characteristics, reproduction, causes of changes in natural resources, applied conservation measures of species belonging to the Rosa L. genus in Azerbaijan on scientific basis. The research has used the research work of many botanists and my personal research. Numerous expeditions and monitoring were carried out in the research work, 64 species of Rosa L. genus were found in the natural and cultural conditions in the republic. Observations have shown that the range of most species of the Rosa L. genus has been reduced, and some are endangered. The research analyzed the reasons for the reduction of the habitats of 33 species of 64 species of the Rosa L. genus, the risk criteria of these plants according to version 3.1 of the IUCN.
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Rare types including Iridaceae juss. of the Garagush mountain
Статья научная
The genus Iris Tourn. ex L. of the family Iridaceae Juss. there are 200 different species in the Northern Hemisphere. There are more than 30 species of this genus in the territory of the Republic of Azerbaijan, some of which are endemic to Azerbaijan or the Caucasus. All irises are decorative and used in ornamental gardening. Iris caucasica Stev. ( Iris caucasic a Hoffm.) and I. lycotis Woronow ( Iris iberica subsp. lycotis (Woronow) Takht.) grows on rocky and grassy slopes of The Garagush Mountain. Iris caucasica Stev. is included in the Red Data Book of Nakhchivan AR as an important subcatagory of protection with the status of Lower Risk - LR (a - Conservation Dependent - CD). Iris lycotis Woronow has been to its activity and other abiotic factors, its range is reduced its biology is poorly studied and it is included as an endangered species in the Red Data Book of Nakhchivan AR with the status of Near Threatened - NT. Species included in this category should be enshrined in special protected areas and their biological characteristics should be studied.
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Ravines floristic diversity of Khinna gorge (Zayamchay river basin, Lesser Caucasus)
Статья научная
In 2016-2021 the ravines floristic diversity of the Khinna gorge (Zayamchay river basin, Lesser Caucasus) was studied. Khinna gorge is located on the right bank of the Zayamchay river, at the foot of Gizilja Mount. In the ravines of the Khinna gorge, 18 species, 13 genera and 11 families of plants were found. Plants of relict origin were also found: Poa nemoralis L., Poa compressa L., Ulmus glabra Huds., Parietaria chersonensis (Lang & Szov.) Dörfl., Asparagus verticillatus L., Gladiolus atroviolaceus Boiss., Rubus buschii Grossh. ex Sinkova, Amoria tumens (Steven ex M. Bieb.) Roskov, Plantago major L.
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Reforms in the railway system during the Second World War
Статья научная
The first railway lines in the Surkhandarya oasis, the influence of railways on the cotton industry, the start of new electric locomotives in order to bring raw materials to the center as quickly as possible, and the industrial enterprises moved to the region during the Second World War were covered based on scientific literature and archival materials.
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Статья научная
The article presents statistically significant regression models ( R 2corr>0,9; Fcr>>100; response function - life expectancy). The analysis of the abnormal observations in the baseline information has been carried out according to an original approach
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Статья научная
Feed plants are dynamically utilized by humans. This leads to a decreasing supply of feed plants. Also, considering that feed plants are eaten by animals, it can be observed that the decrease in the supply of these crops is inevitable. For this purpose, we studied the rare species of feed plants in the vegetation of Gunnut-Kapychik physiographic area where we conducted our research. The list of rare species distributed in the area is given by determining the distribution of feed plants in the area by altitudinal belts. Along with internationally recognized categories for determining the status of some important species, rare and endangered in nature, their relationship with the biome is also recorded. First of all, its past and present state in nature, its limiting factors are clarified and included in one of the relevant categories.
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Статья научная
Comparative analysis of modern interpretations of Chekhov’s “The Cherry Orchard” in the film and on the stage as an example of exemplary modern directorial works offered in this article. The basic idea: to Chekhov production was authentic and the audience understood, modern director must translate it into the language of art era, without compromising the reliability of the text.
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Relations of sovereign Kyrgyzstan in the economic and social spheres
Статья научная
Kyrgyzstan strives to strengthen and deepen mutually beneficial cooperation in all sectors of the national economy. When forming economic and social ties, the Kyrgyz Republic also primarily paid attention to the development of relations with the CIS countries, especially with Central Asia and Kazakhstan. 90’s. in the first half of the year, Kyrgyzstan’s export-import relations were Russia, Kazakhstan, Uzbekistan, Ukraine, Turkmenistan, Tajikistan, and Belarus, followed by Kazakhstan.
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Статья научная
In research work have been extensively studied morphological aspects of seedlings on a scientific basis, propagation by seeds and cutting methods on the Absheron Peninsula species of Jacaranda mimosifolia belonging to the genus of Jacaranda Juss. of the family Bignoniaceae. The research analyzed the sowing period of seeds, soil characteristics, sowing depth, initial germination period, morphological features, agrotechnics, disease and pest control measures. Studies have shown that Jacaranda mimosifolia has the ability to adapt to open and greenhouse conditions in Absheron - in the autumn began to appear the first seedlings in the first decade of October from the seeds sown in the second decade of September in a greenhouse condition, were obtained 4.6% of seedlings at the end of the growing season. In the spring began to appear the first seedlings in the third decade of April from the seeds sown in the first decade of April, were obtained 5.2% of seedlings at the end of the growing season. In the second decade of May 20-30 cm tall plants were transplanted to open fields. At the end of the growing season the length of the compound leaves of annual plants reached 14×15 cm. Plant height reached 1.2 m in height, 1.2-1.5 mm in diameter, stalks reached 16 cm in length, 0.2 cm in width. There are 20 leafstalks on 1 leaf. Keeping the temperature in the greenhouse at 22-24 °C from April to the second decade of October had a positive effect on plant productivity. As a result of the research, it was found that in Absheron conditions the plant shed their leaves in the greenhouse at a temperature below 14 °C. As a result of the research, it was found that Jacaranda mimosifolia has the ability to adapt to open and greenhouse conditions in Absheron, it is profitable to use such an ornamental plant in the construction of parks and gardens, in decoration of offices and interiors.
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Research and protection of the coastal psammophyte-desert vegetation of Absheron national park
Статья научная
Absheron National Park was established based on Absheron State Nature Lowland in 783 hectares of the territory of Khazar district of Baku city by the decree of the president of the country on February 08, 2005; the main purpose is to provide the protection of environment, efficient use, protection of endangered rare plant species, the development of ecotourism, organization of the tourism and recreation zones and environmental enlightenment. For this purpose, the geobotanical research of the psammophyte-desert vegetation formed in the ecosystem (biogeocenosis) of Absheron National Park which located in the part of Suiti cape and Shahdili of the Caspian Sea in Absheron peninsular were executed by the method of “route” on May-June of 2018-2019 and the following were identified. As it can be seen from “The classification of the vegetation of Northern and southern Caspian coast” made up by us for the first time, 2 formation classes, 4 formation groups and 7 associations have been determined in the psammophyte-desert vegetation that formed in the territory of Absheron National Park.
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Research of achievement motivation in neurotic, stress-related and somatoform disorders
Статья научная
This paper highlights results of research and analysis of achievement motivation’s patterns at neurotic and psychosomatic disorders. Interest to research of this medical-psychological problem is connected with goals of changing of motivation’s pathological patterns among this group of individuals. The research sample included 65 respondents of psychotherapeutic department. The study was conducted using the following methods: test by Hekhauzen; test “Diagnostics of motivational structure of personality” by Milman, questionnaires “Big Five” Obtained results of research show that neuroses in people are the result of internal conflict and anxiety.
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Research of acoustically improved Helmholtz resonator
Статья научная
The three-dimensional acoustic finite element method is used to predict the transmission loss of the Helmholtz resonance muffler. The results are in good agreement with the experimental results, indicating the applicability and accuracy of the numerical method used in this paper. On the one hand, in order to reduce the resonance frequency without changing the shape of the resonator, the connecting tube is extended to the inside of the resonator, and the influence of the extension length and the cross section shape of the extension tube on the acoustic characteristics of the resonator is discussed in detail. On the other hand, in order to broaden the muffled frequency band of the traditional Helmholtz resonators, the resonators are combined in series and parallel, and the influence of the combined structure on the acoustic characteristics is discussed in detail.
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Research of indicator analysis of social and economic security
Статья научная
The thresholds represent the subsequent specification of the state interests in the field of socio-economic security risks. They say these aspects of socio-economic security of food, energy, infrastructure, technology, etc. To a significant extent there are recognized difficulties of life support. In this group are required to enter threshold values, characterizing the danger, located on the border between socio-economic and other characteristics of a security, for example, demographic, industrial security, available strategic reserves etc. The more difficult is the question of the quantitative parameters of threshold values. It must be said that the development of methodological approaches to the determination of such quantitative characteristics has proved to be a difficult task, taking into account that there is a very strict criticism about the quantitative characteristics of the thresholds. It is possible to agree with such arguments against the quantitative calculation of thresholds as their lack of real-specific orientation, the controversy of the methods of calculation used, etc.at the same time, the threshold indicators are a real signal of a positive or negative position, a team to the action of the relevant state bodies.
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Статья научная
The ship’s central cooling water system is one of the most important systems serving the main engine. With the progress of society, the design and construction of ships increasingly need to develop in the direction of environmental protection and energy-saving. Taking the 59,990 t bulk carrier as the research object , this paper proposes that based on the frequency conversion control of the seawater pump and supplemented by the energy-saving scheme of pulsation enhanced heat exchange, the frequency conversion control of the seawater pump is realized by adjusting the speed according to different working conditions. At this time, adding pulsation enhanced heat transfer technology can generate forced convection, increase the turbulence of the fluid in the tube, and introduce convection into the boundary layer, and at the same time produce cavitation, which can improve the heat transfer efficiency of the equipment. After using the seawater pump frequency conversion control and pulsation enhanced heat exchange program, the energy consumption is about 36% of that before the system was installed. The data shows that the program achieves the purpose of environmental protection and energy-saving and has a certain reference value for engineering research.
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Research on modeling and simulation of doubly fed induction wind turbine based on MATLAB/Simulink
Статья научная
This paper first introduces the structure of doubly fed wind power generation system and the working principle of doubly fed induction generator in detail and establishes the corresponding mathematical model of doubly fed wind power generation unit. The control part of wind power generation system based on doubly fed induction generator includes rotor side control and stator side control. The rotor side control adopts the vector control strategy based on stator flux orientation of the double-fed induction generator connected to the grid, and the working principle is analyzed in detail, and the main part of the simulation modeling is given. Stator side control adopts vector control strategy of grid-connected inverter control, and its working principle is analyzed in detail, and the main part of simulation modeling is also given. In order to verify the correctness and feasibility of the system, the simulation experiment platform of doubly fed wind turbine under this control strategy is built by using Matlab/Simulink simulation platform, and its simulation analysis is carried out in detail.
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Research on ventilation and heat dissipation performance of trailer power station
Статья научная
The results show that the use of CFD software to simulate the ventilation and heat dissipation of the trailer power station cabin, Get the flow field and temperature field in the cabin, The position of the highest temperature in the vehicle cabin can be determined quantitatively, which provides a useful reference for the design of the cabin structure of the trailer power station and the arrangement of the equipment in the vehicle. Moreover, the simulation results are in good agreement with the experimental results. It shows that the selected Realizable k-ε Turbulence Model can more accurately simulate the air flow field in the cabin of the trailer power station. It also shows that the model simplification method used in the calculation and the setting of analytical conditions are reasonable.
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