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Статьи журнала - Бюллетень науки и практики
Все статьи: 6181
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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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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Synthesis of As2Se3 in organic medium
Статья научная
Arsenic (III) selenide has been synthesized in organic medium by using metaarsenite and amorphous selenium. The synthesis was carried out at the temperature range of 433-443 °K, pH >10, during 2-8 hours. Resulting sediment is filtered, washed at first by 0.1 M of acetate acid solution, then by ethyl alcohol and dried at 353 °K. The chemical analysis of the sediment is made, thermal, X-ray phase analyses are carried out, and electron microscope images of microparticles are taken.
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Synthesis of amides and salts of oxalic acid and their use as plant growth regulators
Статья научная
Oxalic acid plays a very important role in the life of plant organisms. In addition, its salts and amide derivatives also have growth-stimulating properties. In this work, we show the results of research in the field of synthesis of amide derivatives of oxalic acid, and also investigated their growth properties using the example of some agricultural crops. Have found that the mono amide of oxalic acid has a stronger effect on the growth of pea seeds compared to the disubstituted amide of this acid. Thus, we can conclude that salts and amide derivatives of oxalic acid have a pronounced regulatory property during the ripening of pea and corn seeds. In this regard, they have been recommended as growth stimulants for these plants in agricultural practice.
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System of ensuring social and economic security of the industrial sector
Статья научная
The methodological basis for the formation of the system of ensuring socio-economic security includes features of the industrial sector. The specifics of his defense was designed to show with the help of the methodological and operational foundations. Methodological framework is formulated based on the research process the functional specificity provide socio-economic security of the industrial sector. They form the perimeter of ensuring social and economic security, which is formed by the expectations of society from the defense system of the industrial sector of the country. Operating bases are complementary to the functional specificity of the system provide socio-economic security by means of the formation of a specific institutional framework. Among them, the following are noted: modeling, allowing multivariate escalation of adverse events in the industrial sector and methods of its evaluation; instrumental assistance, taking into account the need for instrumental diversity for the implementation of defense functions in changing criteria (the environment of the industrial sector, its structure and the state of inter-element connections); functional coherence as the need to balance the goals of ensuring the socio-economic security of the industrial sector with the objectives and values of the formation of the industrial sector of the country, which are fixed in the policy documents of the state.
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Systematic review of the genus Hypericum L. in flora of Azerbaijan
Статья обзорная
Among the widespread plant species in Azerbaijan, the genus Hypericum L. which dates back to the Cenozoic era and belongs to the family Hypericaceae takes special place. 80% of the total number of species belonging to the Hypericaceae family are concentrated in the genus Hypericum , which is distinguished by its many-sided areas of application, especially in the pharmaceutical, decorative and dye industries. This genus is considered one of the largest genera of flowering plants in terms of species diversity (22%). Although research on the systematics of the genus Hypericum has been conducted by many scientists around the world, the general characteristics and taxonomic composition of the species distributed in the flora of Azerbaijan have not been studied for the last 50 years. As a result of our research, it was determined that there are not 15 species, but 19 species, 1 subspecies and 1 variety belonging to the genus in the flora. The characteristics, descriptions and synonyms of sections, species, subspecies were given.
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Статья научная
In the given article, the flora of Ganja city and its surrounding areas was studied, the plants were systematically, biomorphologically, geographically, ecologically, and endemically analyzed. The article also analyzed rare and endangered plants on scientific basis. In the researched region, 68 families, 244 genera, and 441 species of plants were identified. It is reported that the basis of the flora composition of the territories is angiosperms, the leading families of which are Poaceae with 38 genera (15.6%), 63 species (14.3%), Fabaceae 23 genera (9.4%), 48 species (10.9%); Asteraceae is represented by 15 genera (6.6%), 35 species (7.9%). It was determined that the composition of the flora of the study area is dominated by perennial grasses with 194 species (44%).
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Статья научная
The article presents data on the systematical structure, ecological groups, and areal classes of Rosa L. genus spread in the flora of the Nakhchivan Autonomous Republic. As a result of researches in the Nakhchivan Autonomous Republic, the concept of 30 species of Rosa L genus was developed and spreading of these species by vertical heights, as well as geographic range classes based on regional and zonal principles, were determined.
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Taxonomic analysis of the Cirsium mill. genus in flora of Azerbaijan
Статья научная
The main goal was a systematic analysis of the Cirsium Mill. genus (Asteraceae) in flora of Azerbaijan. Floristic-systematic, comparatively morphological, ecological and other methods were used. In addition, materials stored in the Herbarium Fund of the Botanical Institute of Ministry of Science and Education, Republic of Azerbaijan were studied related to this genus. As a result of the research, it was established that 31 species of the genus Cirsium Mill. are widespread in the flora of Azerbaijan.
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Taxonomic composition and life forms of the family Asteraceae spreading in Daridagh massif area
Статья научная
The article provides information on the taxonomic composition and life forms of the Family Asteraceae Dumort, which is widespread in the Daridagh Massif area. During our research, 43 species belonging to 23 Genera of the Family Asteraceae Dumort spreaded in the Daridagh Massif area. Also, a comparative analysis of the number of species belonging to the Family and their life forms were studied. According to the analysis of the number of species of the Genera Helichrysum Mill. - 2 (4.65%), Taraxacum Wigg. - 2 (4.65℅), Centaurea L. - 3 (6.97%), Carduus L. - 3 (6.97%), Achillea L. - 3 (6.97%), Scorzonera L. - 6 (13.95%) and Tragopogon L. - 8 (18.6%) species are the main predominant species in the Daridagh Massif area and are represented by 27 (62.79%) species. The remaining Genera are monotype and consist of 16 (37.20%) species.
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Taxonomic relationship of wide pests in sugar beet agrocenosis
Статья научная
Based on the conducted research, information on the species composition of pests that spread in the agricultural farms of Imishli and Agdash districts of the Republic, where sugar beet is grown, as well as in the private backyards of the population, was reflected in the article. During extensive research conducted in stationary areas and surrounding areas, it was determined that pests belonging to the groups of Coleoptera, Hemiptera, Orthoptera, Diptera and Lepidoptera are found in the agrocenosis of sugar beet.
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Taxonomic synopsis of salsola genus (Mil Plain, Azerbaijan)
Статья научная
In article the results of analysis conducted on bioecological features of Salsola species which are distributed in desert phytocoenosis of Mil plain of Kur-Aras lowland were given. Materials for research were plant herbaria which collected from researched area, as well as herbarium funds of Baku State University and Institute of Botany Azerbaijan National Academy of Sciences. Morphological study of the flower parts of Salsola species was conducted with Carl Zeiss Stereo Discovery V4 stereomicroscope. It was determined that in researched area 10 species ( Salsola australis R. Br., S. tragus L., S. paulsenii Litv., S. soda L., S. nitraria Pall., S. incanescens C. A. Mey., S. dendroides Pall., S. ericoides Bieb., S. nodulosa (Moq.) Iljin, S. foliosa (L.) Schrad.) of Salsola genus are distributed. Their morphology, ecology, systematical position, as well as economic significance were analyzed. It was also found that an anthropogenic impact in this area leads to desertification of landscapes.
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Teaching English grammar through interactive methods
Статья научная
The article is devoted for the effective ways of teaching grammar. Actuality of the theme is justified as it sets conditions for revealing high progress in teaching a foreign language and for developing effective methods which can be helpful for foreign language teachers. Different progressive methods of teaching English grammar are given in this paper as well.
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Teaching English language in heterogeneous classrooms
Статья научная
The article aims to provide a thorough insight into the teaching context of heterogeneous classes in line with identifying their most distinctive features, certain elements that form differences that most often EFL teachers note challenging. Based on needs evaluation it is possible to create a successful learning environment where efficient lesson plan assisted by credible techniques will be united around a single concept of a competent teacher ready to espouse the students who need support.
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Teaching methods of English for specific purposes
Статья научная
Foreign Language Teachers for Specific Purposes have a lot in common with teachers of general foreign language. For both it is necessary to consider linguistic development and teaching theories, to have insights in contemporary ideas regarding their own position and role as well as the position and role of foreign language learners in education and to face new technologies offered as an aid to improve their methodology. The most important difference lies in the learners and their purposes for learning English. ESP students are usually adults who already have some acquaintance with English and are learning the language in order to communicate a set of professional skills and to perform particular job-related functions. An ESP program is therefore built on an assessment of purposes and needs and the functions for which English is required.
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Teaching practice for the 21st century: challenges and prospects for teacher education in Uzbekistan
Статья научная
The paper considers the interrelation of the problem of maintenance of quality of higher education and professionalism of the teacher. The result of the research made it possible to prove the value of professionally important qualities of the teacher in the improvement of the quality of educational services in the conditions of competitiveness of higher education system. Qualitative foreign teaching is one of the most important key characteristics defining the professional competence of a higher school graduate as a whole and is considered from the point of view of systemacy, of integral content, of teaching technologies, of methods of control and assessment of the results.
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Teaching spoken French in FFL (French as a foreign language)
Статья научная
The dispute has never stopped surrounding the use of familiar language in the French teaching. Lots of people consider that the familiar language is really vulgar which is not an appropriate type of language for the elegant scenarios, and the same people insist that this kind of language should be locked out of the classroom in order to ensure the correct and authentic usage of French. As a matter of fact, every type of language will never be isolated from the final practical use. The familiar language has the most intimacy with the daily life of the French people and it’s the language that they are using every single day. Compared with the standard French, the familiar language might be even more important in terms of communication and pragmatics. Most French speakers use colloquial French, especially in informal spaces.We can see that colloquial language is greatly underestimated in learning, specifically in learning French as a foreign language. How to define the meaning of familiar language? What is its role in the teaching and study process of French? How to properly clarify the relationship between standard French and familiar language to further improve students’ listening and speaking ability in communication? These are the questions to be discussed in this article.
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Teaching the language of the mother drama from the lexical-semantic and morphological point of view
Статья научная
Huseyin Javid succeeded in bringing the language of poetry to the stage for the first time with the Mother verse drama. He is a master of powerful artistic monologues. The dramatist builds monologues so skillfully that the character’s inner hand, outlook on life, society, heart palpitations, tremors, excitement and other feelings attract the attention of the reader at the first moment. H. Javid was a lover of contrasts. M. C. Jafarov clearly observed that in this work opposite moral qualities such as generosity and selfishness, bravery and cowardice, simplicity and arrogance were contrasted, and all these were shown in living characters. An important aspect is added to this, that here the images were divided into two fronts based on their positions and moral and spiritual qualities: the poor and the rich. Therefore, the author also saw the main contradiction in the socio-political situation and showed it as an irreconcilable contradiction between the poor and the rich, the powerful and the oppressed.
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