fractional composition
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2021 ◽  
Vol 31 (4) ◽  
pp. 591-608
Author(s):  
Sergey V. Braginets ◽  
Oleg N. Bakhchevnikov ◽  
Aleksandr S. Alferov

Introduction. Developing a method for energy-efficient grinding of fibrous vegetable raw materials to avoid the clogging of grids remains an urgent task. The aim of the research is to study the process of grinding dried fibrous plant materials and to estimate the influence of the device operating characteristics on the quality of grinding and the process energy intensity. Materials and Methods. The experimental apparatus is a rotor grinder. Its working bodies are alternate knives and hammers. When a hammer is in motion, its triangle side creates the reduced pressure area. There was studied the influence of the linear velocities of knife motion and of feed of raw materials on fractional composition of the grinded materials, grinder productivity, and grinding specific energy capacity. Results. It is found that the change in the fractional composition of the grinded product occurs when the speed of the rotor knives increases. Optimal range of knife speed for producing the product of the required fractional composition is 55‒75 m/s. The increase in the speed leads to increasing productivity, but is accompanied by the growth of specific power intensity. If the rotor speed is constant, the increase of raw material feed increases the grinder productivity, but only up to a certain value. After that, the productivity decreases because of excessive filling of the working chamber with raw materials and clogging of the grates. For each value of the knife speed, there is an optimal feed that ensures the maximum productivity. High values of knife speed lead to significant energy intensity of the process and overgrinding of raw materials. Therefore, the optimal range of knife speed is 55‒65 m/s. Discussion and Conclusion. Effective grinding of raw materials is achieved through lower energy capacity of grinding process and absence of grate clogs resulted from separating particles from the surface of plants to be grinded.


Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Natalya N. Nikonova ◽  
Tatyana V. Hurshkainen ◽  
Oksana G. Shevchenko ◽  
Alexander V. Kuchin

Abstract In order to explore the extractives of conifers an effective and environmentally friendly method of extraction with aqueous-alkaline solution allowing to isolate up to 10.4% of extractive substances (ES) from pine wood greenery and up to 6.9% from larch wood greenery was investigated. The component fractional composition of aqueous-alkaline extracts was studied. The antioxidant fraction activity of neutral and acidic components isolated from the produced extracts was evaluated. It was found that these fractions have a high antioxidant activity, where the activity of larch extract components was higher than that of the respective components of pine extract. Due to their rich chemical composition and high biological activity, extracts of pine and larch wood greenery produced by aqueous-alkaline extraction have good application prospects as biologically active preparations.


Author(s):  
Vitalii Chumak ◽  
Mariia Maksymiuk ◽  
Olena Kosenko ◽  
Vira Rudenko ◽  
Olena Spaska

Exceptional prospects for use in science, technology and industry are opened by highly dispersed powders (ultradispersed diamonds, nanoceramics, medicinal powders) and materials based on them. The properties of such materials depend on the particle size determined by sedimentation analysis. An equation is proposed for processing sedimentation analysis data, which does not depend on the size distribution law of polydisperse system particles, and is used to describe the distribution functions of particles with radii for clay suspensions. A program in the Microsoft Visual Basic for Applications (VBA) language has been created for calculating the fractional composition of suspensions according to the proposed equation; the correctness of its operation on a model system has been checked and confirmed. Experimental research has confirmed that the use of the developed program and the "Search for a solution" add-on for the MS Excel environment makes it possible to determine the fractional composition of suspensions. It has been proven that the proposed method can be used to analyze polydisperse systems. It has been found that for the suspensions under consideration, as containing 25 fractions, it is possible to determine the integral curve of the distribution of the masses of the particles of the dispersed phase along the radii. This allows to assert the possibility of using the proposed equation for processing sedimentation analysis data, which does not depend on the law of mass distribution of polydisperse system particles by size. Thus, there is reason to assert about the possibility of a reasonable determination of the fractional composition of any polydisperse systems. It is possible to obtain certain effects from the introduction of sedimentation analysis data processing according to the proposed equation in production, where the fractional composition of dispersed phases is regulated.


2021 ◽  
Vol 6 (3(62)) ◽  
pp. 6-10
Author(s):  
Ivan Zezekalo ◽  
Viktor Kovalenko ◽  
Iryna Lartseva ◽  
Olexandr Dubyna

The object of research is the catalytic effect (hydrocracking) for the production of hard-to-recover hydrocarbons, the subject of the study is the change in the physicochemical properties of hydrocarbons by partial gasification, and the lightening of the fractional composition of hydrocarbons. One of the most problematic areas is the lack of studies of the catalytic effect on hard-to-recover hydrocarbons in reservoir conditions. Although processes such as catalytic cracking, reforming, isomerization, aromatization and alkylation of hydrocarbons are known and used in petroleum refining. The research used the methods of scientific knowledge – experiment and measurement. In the course of laboratory work, an effective catalyst was developed, the effect of temperature on the fractional composition and physicochemical properties of oil, oil products and gas condensate was investigated. To simulate formation conditions, hermetic metal retorts were used, in which oil and gas condensate samples were subjected to different temperature regimes. In the process of testing cores saturated with gas condensate, the dependence of filtration on physical parameters – temperature and pressure, fractional composition, specific gravity and viscosity was studied. Laboratory studies have shown a decrease in density and viscosity of hydrocarbons, an increase in core permeability. The effect of catalysis on oil made it possible to increase the volume of light ends distillation from 30 to 60 %, for gas condensate – up to 50 %, which confirms the effectiveness of the method of catalysis of hard-to-recover hydrocarbons. This is due to the fact that the correct formulation and solution of the problem provided adequate results. In contrast to the existing processes of hydrocracking of petroleum products, the proposed method allows you to extract heavy and low-mobile hydrocarbons in reservoir conditions at lower temperatures of 120–150 °С. At the same time, the technology for catalytic hydrogenation of hard-to-recover hydrocarbons will be similar to a typical treatment of a formation with an acid or surfactants. This will make it possible to intensify the commercial reserves of hydrocarbons in the fields that are now classified as hard-to-recover and which account for more than 50 %.


2021 ◽  
Vol 17 (5) ◽  
pp. 22-30
Author(s):  
N. N. Bubnova ◽  
E. A. Bubnov ◽  
S. V. Gvozdetskaya

Due to the rapid growth in the production and consumption of shisha tobacco in the Russian Federation, it has become necessary to improve the technology using optimal ingredient composition in order to create a high-quality and safe tobacco product. The aim of the research is to improve the technology of manufacturing shisha tobacco based on the optimization of its ingredient composition; to study the influence of the fractional composition of raw tobacco on its quality indicators. Fractional composition of raw tobacco in the production of shisha tobacco, as well as for other tobacco products, is important and affects its quality characteristics. Virginia and Burley tobaccos of the American type are the most demanded ones in the manufacture of shisha tobacco [1]. Sometimes oriental-type tobaccos are used in the bag, which are distinguished by high taste and aromatic qualities. Due to the fact that recently there has been an increase in the demand for Doha Arabian tobacco raw material (this tobacco is known as a high-quality product with a high strength and a pleasant, full and harmonious taste), the idea has arisen to manufacture prototypes of shisha mixtures in which Doha tobacco is used [2]. The article presents the research results: to determine the optimal ingredient composition of hookah tobacco; to study the optimal fractional composition of raw tobacco of various types. As a result of the research the chemical composition of raw tobacco of various types has been analyzed, the tasting and organoleptic evaluation of the prototypes carried out and the tobacco raw material most suitable for the production of shisha tobacco determined; the nicotine content in the condensate of prototypes of shisha mixtures with different fractions of raw tobacco determined; the optimal fractional composition for various types of tobacco raw materials, necessary for the production of a quality product determined.


Author(s):  
Р.Н. Голых ◽  
В.Н. Хмелёв ◽  
В.Д. Минаков ◽  
И.А. Маняхин ◽  
Д.А. Ильченко

Исследование механизма разрушения макромолекул под действием ультразвуковой кавитации представляет собой важную задачу. На сегодняшний день известен механизм разрушения макромолекул, основанный на том, что в условиях ультразвуковой кавитации создаются микроскопические зоны экстремально высоких давлений, в которых повышается вероятность актов разрыва макромолекулы. Разрыв происходит тогда и только тогда, когда относительная скорость при соударении макромолекул между собой превышает критическое значение. За счёт кавитации доля макромолекул, относительная скорость которых превышает критическое значение, увеличивается. В статье описана предложенная численная модель, которая предназначена для выявления молекулярных весов образуемых фрагментов при соударении. Предложен способ уменьшения количества неизвестных функций в 4 раза по сравнению с полной системой уравнений механики мономерных звеньев, основанный на симметрии в предлагаемой постановке задачи. Численно исследовано влияние взаимной ориентации макромолекул олигомеров на количество образуемых фрагментов. Полученные результаты могут служить ориентиром для развития макроскопической кинетической модели эволюции фракционного состава мономерных звеньев (эволюции концентраций мономерных звеньев различных типовых весов). The study of the mechanism of destruction of macromolecules under the action of ultrasonic cavitation is an important task. To date, the mechanism of destruction of macromolecules is known, based on the fact that microscopic zones of extremely high pressures are created in the conditions of ultrasonic cavitation, in which the probability of acts of rupture of the macromolecule increases. A rupture occurs if and only if the relative velocity when macromolecules collide with each other exceeds a critical value. Due to cavitation, the proportion of macromolecules whose relative velocity exceeds the critical value increases. The article describes the proposed numerical model, which is designed to identify the molecular weights of the fragments formed during collision. A method is proposed to reduce the number of unknown functions by 4 times compared to the complete system of equations of mechanics of monomeric links, based on symmetry in the proposed formulation of the problem. The effect of the mutual orientation of oligomer macromolecules on the number of fragments formed has been numerically investigated. The results obtained can serve as a guideline for the development of a macroscopic kinetic model of the evolution of the fractional composition of monomeric units (the evolution of concentrations of monomeric units of various typical weights).


2021 ◽  
Vol 6 (48) ◽  
pp. 2-2
Author(s):  
Olga Kameneva ◽  
Oksana Kibalnik ◽  
Irina Efremova ◽  
Dmitry Semin ◽  
Yuri Kalinin

The ability of sugar sorghum plants to accumulate 18-24% of water-soluble sugars in the juice of stems expands the potential of the crop as a raw material for the production of not only feed (green feed, silage), but also in various areas of the processing industry for food (glucose-fructose syrup, sorghum honey) and technical purposes (bioethanol, biofuels). The brief review presents data on the origin; biological features of sorghum; on the fractional composition of water-soluble sugars; on global trends in the use of renewable energy sources. The advantage of growing Sorghum saccharatum as a sugar carrier in regions with insufficient moisture is reflected. Keywords: SUGAR SORGHUM, WATER-SOLUBLE SUGARS, FRUCTOSE, GLUCOSE, SUCROSE, SUGAR SYRUP, BIOETHANOL, BIOFUEL


Author(s):  
М.Л. ДОМОРОЩЕНКОВА ◽  
Т.Ф. ДЕМЬЯНЕНКО ◽  
И.М. КАМЫШЕВА ◽  
И.В. КРЫЛОВА

Исследования фракционного состава белков и жирнокислотного состава масел безалкалоидных и малоалкалоидных сортов люпина для производства кормов и продуктов питания являются актуальными в современных социально-экономических условиях, когда требуется найти альтернативу соевым продуктам. В данной работе изучались фракционный состав белков и жирнокислотный состав масла семян 11 образцов малоалкалоидных сортов люпина отечественной селекции трех видов: белого, желтого и узколистного. Самое высокое содержание сырого протеина выявлено в образцах семян желтого люпина, в семенах белого люпина содержание сырого протеина было немного ниже, а все исследованные образцы сортов узколистного люпина характеризовались самым низким содержанием сырого протеина. Суммарное количество растворимых белков в семенах люпина было высоким и изменялось от 84,21 до 92,45 %. Во всех исследованных образцах сортов белого люпина преобладала альбуминовая фракция, в семенах сортов узколистного и желтого люпина – глобулиновая фракция. Содержание сырого жира в семенах разных сортов изменялось от 4,62 до 9,28%. Обнаружены различия в жирнокислотном составе масла семян люпина разной видовой принадлежности. Жирнокислотный состав семян характеризовался преобладанием олеиновой кислоты в масле семян сортов белого люпина, при явном преобладании линолевой кислоты в сортах желтого и узколистного люпина. Researches of protein fractional composition and fatty-acid composition of nonalkaloid and low-alkaloid lupine varieties oils for food production are actual in modern social and economic conditions, when it is required to find an alternative for soybean products. In the present work, the protein fractional composition and fatty acid composition of seeds of 11 low-alkaloid lupine varieties of domestic selection of three species: white, yellow and narrow-leaved lupine were investigated. The highest content of crude protein was detected in seed samples of yellow lupine, the crude protein content in white lupine seeds was slightly lower, and all the studied samples of narrow-leaved lupine were characterized by the lowest crude protein content. The total amount of soluble proteins in lupine seeds was high and varied from 84,21 to 92,45 %. In all examined samples of white lupine varieties the albumin fraction dominated, while in seeds of narrow-leaved and yellow lupine varieties the globulin fraction dominated. The crude fat content in the seeds of the different varieties varied from 4,62 to 9,28%. Differences were found in the fatty acid composition of lupin seed oil of different species. The fatty-acid composition of seeds was characterized by the predominance of oleic acid in the oil of white lupine varieties, with a clear predominance of linoleic acid in yellow and narrow-leaved lupine varieties.


2021 ◽  
Vol 937 (3) ◽  
pp. 032042
Author(s):  
Viktor Pakhomov ◽  
Sergey Braginets ◽  
Oleg Bakhchevnikov ◽  
Aleksander Alferov

Abstract The energy-efficient crushing of dried fibrous plant materials is usually hampered when the sieve holes of the crushing unit are clogged with not-grinded particles. The purpose of the study was to investigate the crushing process of dried plant raw material and determine the effect of the operating modes of a crushing unit on the crushing quality and energy consumption. The experimental tool was a rotary crushing unit with alternate knives and hammers. The objects of crushing were dried leafy mass of grass. There has been found that when the linear speed of the rotor knives rises, the fractional composition of the crushed product changes, namely, the proportion of fine fraction (less than 1.3 mm) increases and the proportion of large particles (more than 1.3 mm) reduces. The rise of the knives speed results in productivity improvement, but increases energy consumption of crushing as well. The optimal range of changing the knives’ speed was 55…65 m·s-1 to obtain a product of the required fractional composition. The use of the method of crushing dried fibrous plant materials and a rotary crushing unit will allow organizing energy-efficient crushing of dried leafy stem mass.


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