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Статьи журнала - Бюллетень науки и практики
Все статьи: 5660
Epizootological state of salmonella-infected honeybee colonies in the southern region of Azerbaijan
Статья научная
In 2020-2021, the number of apiaries and honeybee colonies in villages located in 3 regions of the Masalli district (lowland, foothill and mountainous territories) and the degree of their infection with salmonellae were determined. Salmonellosis is one of the characteristic diseases of honeybee colonies, widespread throughout the Masalli district. Infection of honeybee colonies with salmonellae led to a slowdown in the activity of colony, a decrease in productivity, and even the death of the honeybee colony. As a result of the conducted studies, the epizootological state and the degree of salmonella infection were detected in the lowland (24.1%), foothill (38.0%) and mountainous (45.8%) areas.
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Estimation methodology of efficiency of production capacity management at textile enterprises
Статья научная
In this article have been made an attempt to develop theoretical provisions and methodological recommendations for evaluating the efficiency of managing the production capacity of enterprises in the textile industry. Methodological basis of this research was works of foreign and domestic scientists-economists in this field. This research has been based on a general scientific methodology that involves the use of statistical analysis and economic-mathematical methods. The practical significance of the research results is that the obtained scientific and methodological results can be used by textile industry enterprises to solve the tasks of managing production capacities. The methodology for assessing the effectiveness of management of production capacity can be used by managers and specialists of textile enterprises in the process of developing measures to increase production capacity and increase the level of their use. The developed by the author results of the research are proposed for use in the educational process when studying the disciplines “Enterprise Economics”, “Operational Management”, “Production Management”, “Production Management” by students and students of economic specialties of universities.
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Estimation the role of small business in increasing export potential of Uzbekistan
Статья научная
This paper studies the role of small business in the economy and its sectors in Uzbekistan, as well as estimates their role in increasing and diversifying the export potential of Uzbekistan. Moreover, gives a brief and short description and results of reforms and programs held in the creation of a favorable environment for small business. As consequences of those reforms, the number of small business in Uzbekistan increasing steadily. Also acknowledged that agriculture plays a great role in the expansion and diversification of export in the state since it has absolute and comparative advantages in external trade. The share of small business in GDP have a positive high impact on the total amount of export 241.9 million dollars. Moreover, calculations show that there is high elasticity between the share of small business in export and GDP, industry, agriculture high enough. Conclusions indicate the role of agriculture especially small business in agriculture is very effective in increasing the share of small business in export.
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Статья научная
The prevention of hereditary diseases associated with gene and chromosomal disorders, in particular multifactorial-polygenic diseases is one of actual areas of medical genotyping. For the first time in the population of the Republic of Azerbaijan we have identified mutations C174T and C235T of the angiotensinogen gene and mutation C677T of the methylenetetrahydrofolate reductase gene both in the control group and among patients with diseases of the cardiovascular system. Reliable connections for the frequency of occurrence of polymorphism of the C174T and C235T alleles of the angiotensinogen gene and polymorphism of the C677T allele of the methylenetetrahydrofolate reductase gene were found with a statistical method. To identify the ethno-geographic relationship of the mutations C174T and C235T of the AGT gene for the population of the Azerbaijan Republic, we examined practically healthy individuals and patients with CVD. The composition of this group was multinational and corresponded to the main national and ethnic composition of the Republic. The distribution of the identified mutations C174T and C235T of the AGT gene, as well as the C677T polymorphism of the MTHFR gene among ethnic groups of the Azerbaijan Republic is identified as uneven.
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Статья научная
The research was carried out in the arid regions of Azerbaijan in 2021-2023. The main goal of the research was to provide a bioecological and phytocoenological analysis of species of the genus Chenopodium , widespread as a weed plant, in the composition of coenosis, and to reveal the possibilities of use based on ethnobotanical surveys among the population. Floristic, phytocoenological, ethnobotanical methods were used during the research. It was determined that 15 species of the genus in Azerbaijan flora are more widespread in the plains and mid-mountain belt, mainly in the desert, semi-desert steppe vegetation, and in cultivated areas. During the surveys conducted among the local population, it became clear that only 10 species of the genus are used, of which 5 species are used only as wild vegetables, 3 species are used only for treatment in folk medicine, and one species - Chenopodium album is used by the population both as a medicinal plant and as a vegetable plant. It has been recorded that one species ( Chenopodium foliosum ) of the genus is used as a dye plant.
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Etymological specificity of English-language ecology terms
Статья научная
The anthropocentric paradigm in linguistics, which brings to the fore the study of the human-language relationship, also correlates with the socio-ecological terminology: for the humanities, which includes philology, the terms of greatest interest are those that reveal various aspects of human interaction with nature, human influence on biological processes at various levels: from the micro-level (soil cultivation, cattle breeding, etc.) to the macro-level (global environmental disasters, space debris, etc.). The present article is an attempt to study the etymological specificity of English-speaking ecology terms in terms of anthropolinguistic approach.
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Evaluating the intellectual ability of entrepreneurship subjects and managers in market conditions
Статья научная
The article provides an overview of the current methods for evaluating the intellectual capital of the organization, analyzes techniques that allow to assess both the intellectual capital in general and its individual components. The author proves that entrepreneurship currently occupies an important niche in the economy of the state. But the insufficient elaboration of questions in science about the psychological characteristics of entrepreneurs, the fragmented and multifaceted information predetermine the directions in the study of this issue. The problem of studying the psychological characteristics of the entrepreneur is relevant for the present time. In general, the author developed a methodology for assessing the intellectual ability of entrepreneurs.
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Статья научная
In the research work, 32 were local (materials of the “Cereals and Legumes” Department of the Institute of Genetic Resources of ANAS) and 25 were introduced by CIMMYT (International Center for Maize and Wheat Improvement), a total of 57 ( Triticum aestivum L.) studied the effect of stress factors on physiological processes of autumn soft wheat genotypes under field conditions, especially drought on the water retention capacity of leaves. Water retention capacity is considered as a very valuable trait of wheat genotypes and is evaluated as resistance to drought stress. As a result of the study, among 57 wheat genotypes, the following genotypes were classified as I- drought resistant (Gobustan (st.) (AZE), Bol wheat (AZE), Grekum75/50 (AZE), Taraggi (AZE), Akinchi84 (AZE), Giymetli 2/ 17(AZE), Sheki 1(AZE), Tale38 (AZE),TX96V2847(US-TX), Arlin/Yuma (USA-KSU), MV Dalma (HU-MV), Desin (RO-FL), Duopebusa (MOL ), SG-S1915 (CZ), U1254-7-9-2-1/TX86A5616//Rina-6)(TCI), II- moderately resistant to drought (Arzu (AZE), Zardabi (AZE), Durdane (AZE), Mirbashir128 (AZE), Nurlu99 (AZE), Ruzi84 (AZE), Aran (AZE), Murov2(AZE), GobustanS2 (AZE), Starshina (RUS-KR), MV06-02 (HU-MV), Gerek (TR- ESK), Gloria (RO-FL), Bezostaya1(TR-ESK), LC924/Petja (BG-SAD), Sonmez (TR-ESK), Dalnitskaya (UKR)) and III- drought (Birlik (AZE), Gurgane 1 (AZE), Karabakh10 (AZE), Parzivan 1(AZE), Parzivan 2(AZE), Azeri (AZE), Saba (AZE), Zubkov (KYR), Steklovidnaya 24 (KAZ)) are grouped as sensitive.
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Статья научная
In this study, evaluated some morphological traits and genotypes by multivariate statistical methods in some oak species ( Q. castaneifolia C. A. Mey, Q. pedunculiflora C. Koch., Q. iberica Stev., Q. macranthera Fisch. & C. A. Mey ex Hohen, Q. ilex L.). 910 leaves were sampled from 91 trees, 8 population across Azerbaijan, and 6 morphological traits were assessed. The indicator traits were analyzed using multidimensional statistical analysis for each species. As a result of the component analysis, the three-pointer element (PRIN1, PRIN2, PRIN3) explained 86.97% of the variance among genotypes. These results provide identification of valuable species and patterns in the future selection and application of other genetic programs on the improvement of oaks in Caucuses.
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Статья научная
The present study characterized the macrobenthic entomofauna of the Sardinas river and the La Delicia stream. Their environmental quality water was determined by applying the BMWP/Col (Biological Monitoring Working Party for Colombia) index in two sampling points, distributed in the Sardinas river and La Delicia stream, during the months of May and June 2017. For its collection, a Surber net was used. In the laboratory, they were classified and identified in class, order and family levels. The specimens were analyzed by calculating the richness (S), abundance (N) and relative abundance (%). A total of 90 individuals belonging to 16 morphospecies were collected. The Hemiptera order with the Veliidae family was the most abundant, encompassing most of the organisms collected 33.33%. The less represented group was the order Diptera with the family Tipulidae with 1.52% of the individuals collected. The water quality was Moderate for the river Sardinas (BMWP/Col 59) and Good for the La Delicia stream (BMWP/Col 75). The present study characterized the community of macroinvertebrates in the study area and the ecological quality of the studied bodies of water.
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Evaluation of winter wheat genotypes under rainfed farming conditions
Статья научная
Drought has a serious effect on the plant height, the heading date and the grain yield of winter wheat genotypes in Mountainous Shirvan. Genotypes of Sonmez 01, Sheki 1, Bezostaya 1 and Gyzilbughda were noted as the tallest (120.1, 118.9, 114.9 and 111.8 cm), Gyrmizigul 1, Guneshli, Tale 38, Aran, Zirva 85 and Azamatli 95 as the short (83.6, 92.8, 95.8, 92.9, 94.0 and 98.0 cm), respectively, which indicates the adaptability of tall varieties for rainfed conditions. Gobustan, Zirva 85, Ruzi 84 and Gunashli genotypes were noted as the early heading, and Bezostaya 1, Sheki 1, Aran, Tale 38, Gyrmizigul 1 and Baba 75 as the late heading, which is associated with their genotypic characteristics. The yield was changed depending on the genotypic characteristics and annual total precipitation during the growing season. The highest yield was recorded in Gobustan and 7WON-SA no. 465 genotypes, while the lowest yield was in Azeri, Bezostaya 1 and Murov 2 during the research. Adaptation to adverse conditions and high yielding of Gyrmizigul 1 genotype shows the possibility of cultivation under adverse conditions. By adaptability to drought high yield of genotypes can be obtained responding to high soil fertility and favorable climatic conditions. Cultivation of these genotypes in rainfed regions such as Mountainous Shirvan is recommended.
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Статья научная
In the context of increasing competition in the banking market, increasing regulatory requirements for transparency and sound risk-creation on this basis of adequate risk provisions in the banking sector is of paramount importance. In this paper, firstly it is proposed to use for estimating credit risks the exact maximum likelihood estimators (MLE) of the structure of stratified population for any sizes of the credit portfolio. These exact MLE could be applied to estimate Basel-II risk parameter PD (Probability of Default), and could be used to optimize provisions for covering expected losses of consumer credit portfolio. In usual banking practice for estimating risk parameter PD the frequencies (rates) of default credits of the whole consumer portfolio or of sub-portfolios of the whole consumer portfolio are usually using. But the statistical characteristics of these estimates, such as unbiased property, consistency, efficiency, exact and asymptotic distributions, usually are unknown. The new statistical estimations have derived for characteristics used in vintage analysis of consumer credit portfolio. These estimations for delinquency rates with different DPD (Days Past Due) are the exact maximum likelihood estimators (MLE) of the structure of stratified population for any sizes of the credit portfolio. These exact MLE could be applied to estimate Basel-II risk parameter PD (Probability of Default), and could be used to optimize provisions for covering expected losses of consumer credit portfolio. Making the adequate provisions to credit risks in the crisis conditions is the problem which needs to estimate risks with satisfactory accuracy.
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Experience vegetative propagation Russian olive (Elaeagnus angustifolia L.) in Uzbekistan
Статья научная
Conducting the results of the research work on the studies optimal timing of harvesting and planting stem cuttings Russian olive. The formation of adventitious roots on cuttings Russian olive is dependent on callus. The roots are laid in the cambium of the stem cuttings and breaking through the crust near the pillow or sheet between the callus and bark. Cuttings Russian olive autumn harvesting and spring planting at the end of the growing season gave the best gain in height - 166.7±5.35 cm (diameter of 10.2 ± 0.47 mm). Annuals plants from cuttings Russian olive autumn harvesting had 30 cm long and a height of 179.8±5,09 cm (diameter of 11.1 ± 0.69 mm) and save 88%. The best survival was observed in the cuttings, prepared with annual shoots. By the end of vegetative growth leading to escape the majority of seedlings Russian olive reaches 83-166 cm in height. Maximum 160-221 cm.
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Статья научная
In this research, the thermal-hydraulic performance of plate heat exchanger (Ridan HHN no. 04) used in domestic water system is investigated experimentally. The hot lubrication/water inlet keep temperature and flow rate constant at 72 °C and 0.8-0.1 L/s, the cold-water inlet remained 12 °C with different velocity. Then the convective heat transfer coefficient increases with enhancement of Reynolds number. Moreover, it is observed that Fanning friction factor decreases with an increase of the Reynolds number and it is showed by the figure. Therefore, it is possible to find that the increase of the Peclet number results in an increase of the Nusselt number as well when Peclet number in water - water smalls than 2500. Finally, we get heat exchanging performances of cold side in lubrication/water - water using plate heat exchanger.
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Experimental research on heat dissipation at the hot end of semiconductor refrigeration chips
Статья научная
TEC1-12705 and TEC1-12706 two types of semiconductor refrigeration chips were designed with different hot-end heat dissipation conditions. At the same time, a test device for heat dissipation of heat pipes for heat sinks with separate current input and two-stage refrigeration was designed, and the influence of hot-end heat dissipation conditions on cold-end temperature was analyzed. The test results show that the cold terminal temperature of the semiconductor refrigeration sheet is related to the heat dissipation capacity of the hot terminal. Under the condition of limited heat dissipation capacity, the cold terminal temperature decreases first and then increases with the increase of the input current; and under the condition of ensuring the heat dissipation capacity, the cold terminal temperature decreases with the increase of the input current and decreases with the decrease of the hot terminal temperature. The two-piece TEC1-12706 semiconductor refrigeration sheet adopts two-stage refrigeration with separate current input, and the minimum temperature of the cold terminal can reach -36,8°С. The test results show that improving the heat dissipation conditions of the hot end can improve the performance of a single semiconductor refrigeration sheet. At the same time, under the best heat dissipation conditions, the use of separate current input two-stage refrigeration can greatly reduce the temperature of the cold end, which is of great significance to improve the working temperature difference of the semiconductor refrigeration sheet.
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Experimental study of cavitation heat generator for heating water
Статья научная
The energy released by cavitation is a new method to make full use of energy. Based on this, a new type of cavitation heat generator for heating water is designed. A conical core is used instead of the traditional throttling element to build a set. Closed circulation system device, the performance of the cavitation heat generator when the cone core with different cone angles was tested in the test. The temperature difference and pressure difference before and after the three groups of liquid medium flow through the cavitation heat generator were measured experimentally. The results show that the cavitation heat generator with a 30-degree tapered core has the best performance and improves the heating efficiency of the feed water, which has a great reference value for the further study of cavitation heat transfer.
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Experimental study on a pulsation-enhanced heat transfer device
Статья научная
The pulsation-enhanced heat transfer technology is introduced, and a volume coil heat exchanger is designed. A pulsation valve is installed at the heat exchanger outlet of the heat exchanger to pulsate the heat medium, and the same heat exchanger is subjected to pulsation and non-pulsation heat transfer tests. Based on the experiments, combined with the theory of pulsation-enhanced heat transfer technology, heat transfer capacity, heat flow, and convective heat transfer coefficient coefficients, the effective temperature difference, heat flow, and convective heat transfer coefficient of the heat exchanger at different pulse frequencies are analyzed. The relationship between the pulsation frequency of the heat transfer effect of the heat exchanger is obtained. The test results show that the heat exchanger has higher heat exchange efficiency when there is pulsation under the test conditions.
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Experimental study on heat transfer and pressure drop in plate heat exchanger using water-water
Статья научная
It would be misguiding to consider only cost in design of a heat exchanger because high maintenance costs increase total cost during heat exchanger’s services life. Therefore, exergy analysis and energy saving are very important parameters in heat exchanger design. In this study, the effects of pate heat exchanger (PHE, Ridan HHN no. 04) on heat transfer, friction factor and exergy loss were investigated experimentally. Experiments were conducted from laminar flow condition to turbulence flow condition under counter flow condition. Reynolds number and Prandtl number were in the range of 220
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Experimental study on heat transfer of pulsating flow enhanced the plate heat exchanger
Статья научная
We conducted two sets of experiments, one is under steady-state conditions and the other under pulsating conditions. We focused on measuring the heat transfer characteristics of plate heat exchangers under different pulsation conditions. In the experiment, we control the mass flow of the hot fluid to circulate at a rate of 0.722 kg/s. The mass flow rate of the cold fluid is 0.05-0.18 kg/s, and the pulsation frequency is 0.45-2.23 Hz. We measured different mass flows at different pulsation frequency. The data analysis shows that when the pulsation frequency is 1.78 Hz, the heat transfer coefficient reaches a maximum of 4415.73 w/(m2·k), and the corresponding cold fluid mass flow rate is 0.155 kg/s, and compared with the heat transfer characteristics of the plate heat exchanger under steady flow, it is found that the average increase in the heat transfer coefficient during the transition to the pulsating mode was 20%.
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Experimental study on unidirectional flow characteristics of flow diode
Статья научная
Flow diode is a kind of control fluid one-way flow of components, it has many advantages, such as simple structure, no rotating parts, no need for external control, power, high reliability, in the medical industry, nuclear industry, petrochemical industry, flow diode has a wide range of applications. By studying relevant literature, combined with the actual situation, based on the experimental study method, using air pump, pressure regulator, 3 d printers and other laboratory equipment, by changing the pump seal the air inlet, simulation of different flow diode under different conditions make the fluid flow through, will pump displacement into displacement, record each air inlet in unit time displacement, and then compared these data, the flow is obtained by carefully analyzing the flow characteristics of diode and the relationship between the fluid flow characteristics diode, it is concluded that: the displacement increases with increase of voltage; when the aperture changes, the flow diode will produce important changes; unstable flow characteristics of variable diameter flow diode.
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