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Статьи журнала - Бюллетень науки и практики
Все статьи: 6181
Acoustic performance analysis of diesel engine silencer
Статья научная
The finite element model of diesel engine muffler is established, the noise reduction function of the muffler is studied and tested, the distribution cloud diagram of sound pressure level inside the muffler is calculated, the sound fields at various frequencies are plotted. The change of sound pressure level inside the muffler is tested. After processing, the line spectrum and octave band results of the transmission loss of the muffler are obtained. The acoustic performance of the muffler can be quantitatively determined by synthesizing the results of the sound field distribution and the transmission loss inside the muffler.
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Active teaching methods as means of developing students creativity
Статья научная
In the article, you can get an answer to such questions as the place of a lecture in education and on the basis of this concept about the content of a lecture, what can and cannot be talked about. You cannot give all the material in a lecture. In fact, both an inexperienced teacher and a teacher with vast experience can make one methodological mistake: they want to include all their knowledge in the lecture. The teacher, trying to have time to present all the prepared material, lectures quickly. This of course reduces the effectiveness of the lecture. This note provides specific suggestions and discusses the didactic and psychological conditions for organizing the lecture. This article is recommended for university professors for use in lectures.
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Activities of a foreign language teacher and professional pedagogical competence
Статья научная
The article discusses the professional pedagogical competence and activities of foreign language teachers. Modern education depends on innovative activity, creativity and adequacy of teachers. Creativity is not only to generate new ideas, but to use essentice aspects in the life and to develop spiritual world of the person. Scientists who based on the activities of foreign language teachers defined the competencies of foreign language teachers: professional competence, communicative compotense, general cultural competence. The main competencies which were approved within the standard of Kyrgys Republic: information compotense, social - communicative compotense, self-organising and problem sowing compotense. The effectiveness of teachers. Communicative compotense also was reflacted on the basis of practical observation.
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Статья научная
Antioxidant defense systems have been studied in the mesophyll (MC) and bundle sheath cell (BSC) chloroplasts of maize ( Zea mays L.) leaves cultivated in an artificial climate chamber under various concentrations (0%, 1%, 2%, 3%) of NaCl. The amounts of some of the main products of lipid peroxidation malondialdehyde (MDA) and reactive oxygen species hydrogen peroxide (H2O2) as well as activities of superoxide dismutase (SOD) and ascorbate peroxidase (APO) were determined in MC and BSC chloroplasts. BSC chloroplasts were found to be more tolerant to salt stress compared with MC chloroplasts. The MDA amount increased in both chloroplasts. H2O2 was found to be localized mainly in MC chloroplasts at various NaCl concentrations. The SOD and APO activities increased in both chloroplasts of the plants exposed to salt stress.
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Adaptations of Juniperus rufescens Link. leaf's in South Caucasus Mountains (Azerbaijan)
Статья научная
During scientific research in July-August 2019 between 40°53ʹN and 49°25ʹE widths in the Khizi territory (Azerbaijan), adaptations of the structure of the juniper leaves were studied. The leaves of the red juniper have a lancelet appearance and easily vary in different environmental conditions, for this reason we selected red juniper as the object of our studies and measured the length of leaves taken from different tiers. It was revealed that there is an inverse correlation between leaf lengths and altitude from the sea level.
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Addendum to the fauna of venomous snakes of Nakhchivan (Azerbaijan)
Статья научная
The article is devoted to the results of the study of the taxonomic status and ecological characteristics of venomous snake’s species distributed in the territory of the Nakhchivan. Materials for research were collected in various biotopes and landscapes in the highlands during 2011-2023. Information is given on 3 types of poisonous species: Macrovipera lebetina, Montivipera raddei, Pelias eriwanensis .
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Additions to the Apsheron flora
Статья научная
The article provides additional information on the species composition of the flora of the Apsheron Peninsula. The landscape of the peninsula is divided into two unequal parts, which differ orographically. Most of it is represented by the foothills and is located to the west of the peninsula, and a small eastern part is a flat semi-desert - the maximum height is 34 m. Covers natural and artificial ecosystems (semi-desert, middle and low mountain ranges, mud volcanoes, sand dunes and hills, arable lands, settlements). The synanthropic flora was formed here under the influence of anthropogenic factors, and its further adventization is underway. The article includes information about 14 herbarium species, previously common in Apsheron, but not included in the list of flora due to lack of information, and the range and general characteristics of 1 new species. Thus, the number of species distributed on the peninsula reaches 692, which are combined into 385 genera.
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Advantages of logistics guarantee system
Статья научная
The introduction of a system of logistic guarantees in the national economy ensures the stability of products and services and products of new marketing research, a complete study of the consumption of each product (technical, food and other products) that guarantee its production, and prevent mistakes in the country’s development process, and also the bankruptcy of firms. The provision of necessary goods and services for each region is guaranteed; production of unnecessary goods is prevented.
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Aesthetic principles of European and Russian romanticism, Azerbaijani romanticism
Статья научная
At the end of the 18th century, the emergence of the artistic movement of Romanticism in European culture led to innovations in aesthetic approaches not only in this region of the world, but also in a more global environment. Speaking about the genesis of Western European romanticism, one cannot ignore the role of the cultural and philosophical ideas of romanticism in those trends and methods that will be formed in subsequent stages. There is no doubt that the emergence of romanticism was able to change the worldview of people who lived at that stage, influencing all spheres of social thought. However, it is illogical to forget that there is a certain disharmony in the created process.
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Статья научная
In 2013-2018, the spread of 11 species (Anisoplia austriaca (Herbst, 1783), A. segetum (Herbst, 1783) = Chaetopteroplia segetum (Herbst, 1783), Amphimallon solstitiale (L., 1758), Cetonia aurata (L., 1758), Epicometis hirta (Poda, 1761) = Tropinota hirta (Poda, 1761), Melolontha melolontha (L., 1758), Miltotrogus aequinoctialis (Herbst, 1790), Oxythyrea funesta (Poda, 1761), Pentodon idiota (Herbst, 1789), Polyphylla olivieri (Castelnau, 1840), Rhizotrogus aestivus (Olivier, 1789)) belonging to 10 genera (Amphimallon Latreille, 1825, Anisoplia Schönherr, 1817, Cetonia Fabricius, 1775, Melolontha Fabricius, 1775, Miltotrogus Reitter, 1902, Oxythyrea Mulsant, 1842, Pentodon Hope, 1837, Polyphylla Harris, 1841, Rhizotrogus Latreille, 1825, Tropinota Mulsant, 1842) of Scarabs (Scarabaeidae) family of Beetles group has been defined in the stationery fields during the studies in the agroecosystems of Aghdash and Imishli which are the main districts of Azerbaijan planting the sugar beet. During the research’s, detailed information has been collected on the spread, growth dynamics and the damaging effect of 11 species in the agroecosystem. It has been defined that although there is no mass increase and sharp damage between the species during the research years, the monitoring about the number and growth of them should be regularly carried out. However, each species can cause serious damage to the farms during mass growth. Therefore, it is essential to carry out the monitoring constantly in the agroecosystem. The results obtained from the research can be used during the preventive measures for the pests.
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Agricultural terms used in Surkhan oasis
Статья научная
It is analyzed the terms that belong to the agriculture of the Surkhan Oasis such as arable lands, local fertilizers that serve to increase productivity, tools of labor which related to agriculture, names of workers in the field, terms which related to irrigation system in this article.
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Agrochemical characterization of podzolic-yellow soils fertilized for a long time
Статья научная
It is known from our research that in the last 40-50 years, as a result of intensive use of podzol-yellow soils, the reserve and amount of humus reduced, mechanical composition relatively lightened, but relatively stabilization was observed in humus quantity in the areas where the crop rotation was available. It is known that among the agricultural plants, the standard soil for tea plant - weakly podzolic yellow soil has a score of 100 points on the quality scale. Every year application of mineral fertilizers is required in order to get a lot of green leaf crops from the tea plant bushes in terms of soil-ecological requirements. Therefore, physiological acid ammonium-sulfate fertilizer is applied to bushes at a high dose every year. The super-phosphate fertilizer with more gazh in its composition is applied together with nitrogen fertilizer in order to increase its efficiency. In addition to it, potassium-chlorine or potassium-sulfate is applied. According to the research results it can be noted that humus of moderately washed sort decreased 0,1-1,30%, total nitrogen - 0,07-0,08%, absorbed ammoniac - 20,60-40,14 mg/kg, ammoniac dissolved in water - 1,56-4,38 mg/kg, nitrate - 0,24-2,34 mg/kg, total phosphorus - 0,04-0,05%, gross phosphorus - 2,28-23,54 mg/kg, total potassium - 0,14-0,80 %, exchangeable potassium - 50,0-77,4 mg/kg compared to non-degraded sort.
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Agroecological characteristics of irrigated grass-gray soils of the Mil-Mughan economic region
Статья научная
The article provides an interpretation of the agroecological characteristics of irrigated grass-gray soils of the Mil-Mughan economic region and provides extensive information about the physicochemical properties of these soils. Based on studies conducted on irrigated meadow-gray soils, the following results were obtained: the genetic layer of soil 0-55 cm was washed away from easily soluble salts, the humus content in all other genetic layers was 0.3-2.1%, total nitrogen 0.11-0.20%, absorbed bases total 18.0-23.0 mg-eq., physical clay (3, nitrate nitrogen (N/NO3) 3.0-14.0 mg/kg, ammonia nitrogen (N/NH3) 3.0-20.7 mg/kg, C:N - 6.0-7.0, hygroscopic moisture 9.1-4.6%, CaCO3 8.0-17.0%.
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Статья научная
According to the article, grasslands amount for 103,816 hectares out of 5,502.78 km2 total area of Nakhchivan AR. The grasslands play a vital role in the development of livestock, especially rearing of bovine animals, small-horned livestock and beekeeping. Descriptive research work has been conducted in the field, in order to determine the role of grasslands in the development of livestock farming. There is a strong need for conducting study of the area on the basis of landscape planning. As a consequence of a series of natural and anthropogenic factors, a number of environmental issues have arisen on grasslands, and as a result, some areas have become unusable. 58,020 hectares or more than 50% of grasslands became unusable. On the other hand, 45,796 hectares are in good condition. It should be outlined that since destructive factors outpower restorative factors, there is a risk of losing grasslands in the future. It is about time to seriously engage in the solution of environmental problems related to grasslands. Otherwise, we will face bitter consequences. Therefore, landscape planning should be applied in every research work. Hierarchical landscape composition of the area and the problems in each composition should be clearly defined, and the solutions should be developed accordingly. Research work is notably topical in this context.
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Alternative analysis: some new methodology and extension of the real numbers set
Статья научная
Positive definitions made it possible to prove new theorems on well-known objects of analysis: numerical sequences and series. The estimates of the quantity of all primes and the largest of them are obtained. With lineal function at we define Alternative extension of the real numbers set.
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Alternative analysis: the prime numbers theory and an extension of the real numbers set
Статья научная
Here we consider the theory of prime numbers at a new methodology. The theory of prime numbers is one of the most ancient mathematical branches. We found an estimate of the all prime numbers sum using the notions of infinite lager numbers and infinitely small numbers, farther we estimated the value of the maximal prime number. We proved that Hardy-Littlewood Hypothesis has the positive decision too. The infinite small numbers define a new methodology of the well-known function o(x) application. We use the sets of the theory of prime numbers and infinitely small numbers with a linear function to formulate the alternative extension of the real numbers set.
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Ambient media в системе рыночных отношений
Статья научная
В наши дни использование нетрадиционных методов рекламы становится все более популярным. К таким методам относится Ambient Media, для которого характерно использование объектов окружающей среды в качестве рекламоносителя. Ambient Media отличается своей оригинальностью, творческим подходом и изобретательностью, способствует созданию качественного, эмоционального контакта с потенциальными потребителями, созданию положительного имиджа компании.
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Статья научная
Let () and () be two natural variables that is and The pair () () is said to be C -pair if which are as the neighboring elements in Further we prove (Theorem 3) pair () () this pair is C -pair. Let () be natural variable with unlimited step that is d >0 -. Theorem 3 implies that the () with unlimited step can be defined only some subset and is any infinite set. That implies following conclusion (Statement 6). Let be a set of all prime numbers p : p If now it is obvious that | |0 Injective mapping with is said to be potentially antysurjective one (Definition III). Let be (Example 2) square n -matrix with k, m contains of positive rational numbers q, with. Everyone will easily believe that, if we shall assume only distinct numbers in depends essentially on values of the function, for example Now we accept = If we assume a hypothesis that limm( n )»0,6, then we have. (Example 3) Let ( A ) be a harmonic series (Example 3). We prove that ( A ) is the convergent series in addition to it converges to any infinite large number, though it is well known, its sum is not limited by any finite number. See, please, [1, 2].
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Статья научная
The study of the process of migration in aphids has great practical importance. Thus, the aphids pass from one plant to another by these morphs and feed there and maintain their population by growing. The literature information on the research of the photoperiodic reactions in aphids is sufficient. However, the seasonal adaptation characteristics of sugar beet aphids have not been studied up to date in Azerbaijan. For this reason, the study of an impact of photoperiod on the emergence of winged ones in the population of black bean aphid is one of the important issues. During the study of reaction of individuals fed in the same routine against the photoperiod in the next generations, it has been defined that short photoperiod is more observed in the following generations. It seems that the information collected from the former generations is directly passed to the next generations. The results show that the continuous breeding of these species by means of parthenogenesis is only available in the long day (14, 16, 18, 24 hours) routine. However, the winged individuals prevail in the short photoperiods. The preference of winged individuals in 24 hours of photoperiod rather than others (14-18 hours) is probably related to the physiological changes occurs in them.
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Analysis and optimization of the flow path within the protonic ceramic fuel cell stack
Статья научная
With the development of human society, the demand for energy is increasing, and energy, an essential global necessity, is decreasing significantly and is in danger of being depleted. Fuel cell is the fourth power generation facility after hydroelectric, thermal and nuclear power. Fuel cell flow channel is an important part of fuel cell, which has the functions of transferring reaction gas, discharging products and excess unreacted gas, and balancing fuel cell temperature. This thesis focuses on the model design and optimization of a 10-layer flat-plate proton ceramic fuel cell (PCFC) reactor. First, we design a 10-layer flat-plate PCFC reactor model structure, then we simulate the reactor using Fluent, analyze the multi-field coupling operating characteristics inside the target reactor, optimize the reactor based on the results, and finally, we analyze and discuss the optimization results.
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