Characteristics of interpolyelectrolyte complexes of Eudragit E100 with Eudragit L100

With a view to the application in oral controlled drug delivery systems, the formation of interpolyelectrolyte complexes (IPEC) between Eudragit E100 (EE) and Eudragit L100 (EL) was investigated, using turbidimetry, solution viscosity measurements and elementary analysis. The structure of the synthesized IPEC was investigated by using FT-IR spectroscopy. The binding ratio of a unit molecule of EL with EE was found to be approximately 1:1 in pH 6.0. Based on the results of elementary analysis, and FT-IR, the binding ratio of each component in the solid complexes was very close to that observed in turbidity and viscosity measurements and indicate that the synthesized products can be considered as IPEC. Due to the structure of the IPEC, two maxima were observed in the swelling behaviour as a function of pH. The release of the model drug ibuprofen was significantly retarded from tablets made up of the IPEC. © 2004 Elsevier B.V. All rights reserved

Chemical Gypsum as a Building Material for Construction

Секция III : Ресурсо- и энергосберегающие строительные материалы и технологииРассмотрены основные источники загрязнения атмосферы диоксидами серы, их негативное воздействие на экологию, в частности на флору и фауну. Приведены технологические схемы улавливания серного ангидрида. Выполнен анализ эффективности различных технологий очистки дымовых газов тепловых электростанций от серного ангидрида. Отмечена наиболее рациональная схема улавливания диоксида серы с целью получения техногенного сырья для гипсовых вяжущих. Технико-экономические расчеты подтверждают экономическую целесообразности производства строительных материалов из отходов промышленности.=The sulfur dioxide is one of the main sources of air pollution which has a negative impact on the environment, in particular on flora and fauna. This article demonstratesvarious technological scheme of the capture of sulphur dioxide. The analysis of efficiency of different flue gases treatment technologies of thermal power plants from sulfuric anhydride is carried out. The most rational scheme of capture of sulfur dioxide is notedfor the purpose of receiving technogenic raw materials for gypsum binders. Technical and economic calculations confirm the economic feasibility of building materials production from industrial waste

Structural transformations during swelling of polycomplex matrices based on countercharged (meth)acrylate copolymers (Eudragit® EPO/Eudragit® L 100-55)

With a view to the application in oral controlled drug delivery systems (DDS), the design of new interpolyelectrolyte complexes (IPECs) between countercharged types of Eudragit® EPO (EPO) and Eudragit® L 100-55 (L100-55) was investigated. The formation and composition of four new IPECs between EPO and L100-55 were established by elementary analysis. The structure of the synthesized IPEC was investigated using FTIR spectroscopy and modulated-temperature differential scanning calorimetry. The binding ratio of a unit molecule of EPO with L100-55 was found to range between 1:2.75 (Z = 0.36) and 1:0.55 (Z = 1.81) while increasing the pH value from 5.5 to 7.0. As a result of electrostatic interaction between the copolymer chains, the glass transition temperature of the IPEC increased significantly. A large pH-sensitive swelling behavior was observed for different structures of the IPECs. The outcome of swelling and diclofenac sodium release from the polycomplex matrices confirm that they have great potential to be used as a controlled DDS in specified regions of gastrointestinal tract. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association

Chemical Gypsum as a Building Material for Construction

Секция III : Ресурсо- и энергосберегающие строительные материалы и технологииРассмотрены основные источники загрязнения атмосферы диоксидами серы, их негативное воздействие на экологию, в частности на флору и фауну. Приведены технологические схемы улавливания серного ангидрида. Выполнен анализ эффективности различных технологий очистки дымовых газов тепловых электростанций от серного ангидрида. Отмечена наиболее рациональная схема улавливания диоксида серы с целью получения техногенного сырья для гипсовых вяжущих. Технико-экономические расчеты подтверждают экономическую целесообразности производства строительных материалов из отходов промышленности.=The sulfur dioxide is one of the main sources of air pollution which has a negative impact on the environment, in particular on flora and fauna. This article demonstratesvarious technological scheme of the capture of sulphur dioxide. The analysis of efficiency of different flue gases treatment technologies of thermal power plants from sulfuric anhydride is carried out. The most rational scheme of capture of sulfur dioxide is notedfor the purpose of receiving technogenic raw materials for gypsum binders. Technical and economic calculations confirm the economic feasibility of building materials production from industrial waste

Effect of Distributed Photovoltaic Generation on the Voltage Magnitude in a Self-Contained Power Supply System

A promising way to increase the technical and economic characteristics of standalone power supply systems is to incorporate renewable energy installations in their structure. This saves fuel and extends the operational life of diesel power stations. The most common option is a hybrid system with photovoltaic power stations incorporated into the local network of the diesel power station. This paper deals with the dependence of the deflection voltage and power losses in the electric power transmission line on the graphs of electrical loads, the parameters of elements of the power supply system, connection points and the capacity of distributed photovoltaic power stations. Research has been carried out on the common low-voltage power supply systems of the radial type (0.4 kV) with an installed capacity of up to 100 kW. The studies have been conducted by simulating the operating modes of hybrid power systems of various configurations. As a result of these studies recommendations to reduce losses and voltage variations in the network by selecting the power and photovoltaic power connection points have been put forward

Значение видеоторакоскопии в диагностике сложных случаев профессиональных болезней легких

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