scholarly journals Procedure for evaluation of tightness of polymer tanks for transportation of fuel by air

2021 ◽  
pp. 46-48
Author(s):  
D. V. Kolotilin ◽  
A. V. Dedov ◽  
R. I. Kunnap
Keyword(s):  
Coordinate System ◽  
Diesel Fuel ◽  
Diffusion Permeability ◽  
Polymer Materials ◽  
Process Time ◽  
Square Root ◽  
Thermoplastic Polyurethanes ◽  
Conditional Time ◽  
Kinetics Of ◽  
Degree Of Filling

The analysis of methods for assessing the diffusion permeability of polymer materials is carried out. The limitations of the methods for determining the tightness time and the rate of fuel bleeding from elastic tanks based on thermoplastic polyurethanes are shown. To solve the set tasks, an approach is proposed related to establishing dependencies of the kinetics of diesel fuel bleeding in the coordinate system of the conditional time, which was calculated as the square root of the process time. The tightness time and rate of fuel bleeding depends on the degree of filling of the tank during testing.

Kinetics of diffusion and sorption in aging processes of polymer materials (Review)

2021 ◽  
pp. 1-14
Author(s):  
A. A. Dalinkevich ◽  
◽  
L. V. Fomin ◽  
V. V. Melnikov ◽  
T. A. Nenasheva ◽  
...  
Keyword(s):  
Polymer Materials ◽  
Kinetics Of

Study of the permeability of fluorinated high-pressure polyethylene for temporary fuel storage

2021 ◽  
pp. 65-69
Author(s):  
Юрий Николаевич Рыбаков ◽  
Александр Васильевич Дедов ◽  
Роман Игоревич Кюннап ◽  
Сергей Владимирович Ларионов
Keyword(s):  
Molecular Weight ◽  
High Pressure ◽  
Diesel Fuel ◽  
Permeability Coefficient ◽  
Layer Structure ◽  
Storage Period ◽  
High Pressure Polyethylene ◽  
Fuel Storage ◽  
Two Stages ◽  
Kinetics Of

Исследована проницаемость фторированного полиэтилена высокого давления (ПВД), предназначенного для изготовления ремонтных и технологических вкладышей резервуаров складов временного хранения топлива. Использование таких вкладышей позволяет снизить технологические потери углеводородов и увеличить надежность хранилищ из полимерных материалов. В качестве объекта исследования использовали пленки ПВД 10204-003 толщиной 100 мкм. Проницаемость пленок определяли при контакте с бензином марок Нормаль-80, Премиум-95, авиационным керосином ТС-1 и дизельным топливом. Рассмотрен механизм формирования структуры поверхностного фторированного слоя. Исследована кинетика изменения коэффициента проницаемости исходного и модифицированного полиэтилена в течение возможного срока хранения топлив. По результатам исследования установлено: 1) в полиэтилене перенос топлива протекает в две стадии, что определяется раздельной диффузией низкомолекулярных и высокомолекулярных фракций углеводородов; 2) фторирование полиэтилена приводит к уменьшению коэффициента проницаемости (что имеет практическое значение для сохранения качества топлива), но не влияет на перенос фракции углеводородов минимальной молекулярной массы. The permeability of fluorinated high-pressure polyethylene (HDPE), intended for the manufacture of repair and technological liners of tanks for temporary fuel storage has been investigated. As the object of research, 10204-003 HDPE films with 100 μm thickness were used. The permeability of the films was determined by contact with gasoline of the Normal-80 and Premium-95 brands, aviation kerosene TS-1, and diesel fuel. The formation mechanism of the surface fluorinated layer structure was considered. The kinetics of changes in the permeability coefficient of the original and modified polyethylene during the possible fuel storage period has been studied. It has been established that the transfer of fuel in polyethylene proceeds in two stages, which is determined by the separate diffusion of low-molecular and high-molecular hydrocarbon fractions. Fluoridation of polyethylene decreases the permeability coefficient, but does not affect the transfer of hydrocarbon fraction with the minimum molecular weight.

scholarly journals Study on Optimization of Wet Milling Process for the Development of Albendazole Containing Nanosuspension with Improved Dissolution

2020 ◽  
Vol 64 (4) ◽  
pp. 401-420
Author(s):  
Viktor Fülöp ◽  
Géza Jakab ◽  
Bence Tóth ◽  
Emese Balogh ◽  
István Antal
Keyword(s):  
Process Parameters ◽  
Dissolution Kinetics ◽  
Polymorphic Transition ◽  
Milling Process ◽  
Process Time ◽  
Wet Milling ◽  
Influence Of Process Parameters ◽  
Freundlich Equation ◽  
Milling Medium ◽  
Kinetics Of

The main objective of this work was to show the potential of the optimization of top-down wet planetary bead milling process parameters (milling speed, process time and size of the milling medium) by Design Of Experiments (DOE) approach for the development of albendazole (ABZ) containing nanosuspension with improved dissolution. In addition, the influence of process parameters (capacity of milling container, applied volume of milling beads, size of the milling medium, milling speed, milling time) on ABZ polymorphic transition has also been investigated. The optimized, milled formula yielded ~ 145.39 times reduction in mean particle size (182.200 ± 1.3130 nm) compared to unmilled dispersion, which demonstrated 13.50 times gain in mean dissolution rate value compared to the unmilled dispersion in medium at pH = 1.2. No lag time values were observed in the dissolution kinetics of the nanosuspension in comparison with the unmilled samples. Moreover, maximal mean solubility value was also improved by 1.45 times compared to the unmilled suspension, in medium at pH = 6.8, supporting the significance of the Ostwald-Freundlich equation. Diffraction pattern comparisons have indicated a polymorphic transition of albendazole to Form II, which was more pronounced in smaller container at high milling speed values and prolonged operations.

scholarly journals Kinetics of biodegradation of diesel fuel by enriched microbial consortia from polluted soils

2012 ◽  
Vol 9 (4) ◽  
pp. 749-758 ◽  
Author(s):  
E. Moliterni ◽  
R. G. Jiménez-Tusset ◽  
M. Villar Rayo ◽  
L. Rodriguez ◽  
F. J. Fernández ◽  
...  
Keyword(s):  
Diesel Fuel ◽  
Microbial Consortia ◽  
Polluted Soils ◽  
Kinetics Of

scholarly journals Decorative coatings based on the processing of fine waste crushing concrete scrap

2018 ◽  
Vol 196 ◽  
pp. 04048
Author(s):  
Evgeniya Tkach ◽  
Kanapiya Nurbaturov ◽  
Askar Kulibayev
Keyword(s):  
Solid Phase Synthesis ◽  
Solid Phase ◽  
Chemical Interaction ◽  
Drop Out ◽  
Phase Synthesis ◽  
New Compounds ◽  
Kinetics Of ◽  
Degree Of Filling ◽  
Indications For Use ◽  
Rational Range

Experiments were carried out to determine the rational range of the proportion of fillers from sand and the dropout of crushing concrete scrap as a replacement part of the cement to obtain colloidal cement glue and to assess the effect of fillers of different specific surface area and the degree of filling on the kinetics of the set of strength of the hardened stone. It is established that the composition of the concrete scrap crushing drop-out contains about 30% of non-hydrated Portland cement, which deter-mines its use as an active micro-filler in the production of fine cement sys-tems. According to its chemical composition, the elimination of crushing of concrete scrap from heavy concrete is presented in the form of com-pounds of oxide groups, which, as a result of the interaction, provide the process of solid-phase synthesis of new compounds and are not able to en-ter into chemical interaction with pigments, the color of which is deter-mined by the type and content of iron oxides, and therefore has no contra-indications for use in decorative thin-milled cement systems.

Reduced conformal geometrodynamics

2020 ◽  
Vol 35 (02n03) ◽  
pp. 2040023 ◽  
Author(s):  
Andrej B. Arbuzov ◽  
Alexander E. Pavlov
Keyword(s):  
Gravitational Field ◽  
Dynamical Systems ◽  
Coordinate System ◽  
Tangent Space ◽  
Equations Of Motion ◽  
Mean Value ◽  
Hamiltonian Reduction ◽  
Square Root ◽  
The Mean ◽  
Static Background

The global time in geometrodynamics is defined in a covariant under diffeomorphisms form. An arbitrary static background metric is taken in the tangent space. The global intrinsic time is identified with the mean value of the logarithm of the square root of the ratio of the metric determinants. The procedures of the Hamiltonian reduction and deparametrization of dynamical systems are implemented. The reduced Hamiltonian equations of motion of gravitational field in semi-geodesic coordinate system are written.

scholarly journals The Toxicological Testing and Thermal Decomposition of Drive and Transport Belts Made of Thermoplastic Multilayer Polymer Materials

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2232 ◽  
Author(s):  
Piotr Krawiec ◽  
Łukasz Warguła ◽  
Daniel Małozięć ◽  
Piotr Kaczmarzyk ◽  
Anna Dziechciarz ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Degradation Kinetics ◽  
Combustion Products ◽  
Polymer Materials ◽  
Toxic Substances ◽  
Butadiene Rubber ◽  
Different Temperatures ◽  
Increasing Temperature ◽  
In Fire ◽  
Kinetics Of

The article presents the potential impact of flat drive and transport belts on people’s safety during a fire. The analysis distinguished belts made of classically used fabric–rubber composite materials reinforced with cord and currently used multilayer polymer composites. Moreover, the products’ multilayers during the thermal decomposition and combustion can be a source of emissions for unpredictable and toxic substances with different concentrations and compositions. In the evaluation of the compared belts, a testing methodology was used to determine the toxicometric indicators (WLC50SM) on the basis of which it was possible to determine the toxicity of thermal decomposition and combustion products in agreement with the standards in force in several countries of the EU and Russia. The analysis was carried out on the basis of the registration of emissions of chemical compounds during the thermal decomposition and combustion of polymer materials at three different temperatures. Moreover, the degradation kinetics of the polymeric belts by using the thermogravimetric (TGA) technique was evaluated. Test results have shown that products of thermal decomposition resulting from the neoprene (NE22), leder leder (LL2), thermoplastic connection (TC), and extra high top cower (XH) belts can be characterized as moderately toxic or toxic. Their toxicity significantly increases with the increasing temperature of thermal decomposition or combustion, especially above 450 °C. The results showed that the belts made of several layers of polyamide can be considered the least toxic in fire conditions. The TGA results showed that NBR/PA/PA/NBR belt made with two layers of polyamide and the acrylonitrile–butadiene rubber has the highest thermal stability in comparison to other belts.

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