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Laboratory tests of geomechanical properties of Brno clay on reconstituted samples
Rozmánek, Filip ; Koudela, Pavel (referee) ; Chalmovský, Juraj (advisor)
This theses is focused on geomechanical properties of reconstituted Brno clay. The properties of reconstituted soils are different from properties of natural soils because of the ifluence of structure. The properties of reconstituted soils are termed „intrinsic properties“. Object of this theses is to describe these properties and to determine compressibility and strenght charakteristics of Brno clay using reconstituted samples. These charakteristics are obtained using the edometer machine, the triaxial machine and the ring shear apparatus. Calculated data are then compared with known data from literature.
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The influence of micronized poloxamer on the flow and compaction of a model tableting mixture
Dunlap, Brooke Alexandra ; Šklubalová, Zdeňka (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical Technology Supervisor: Assoc. Prof. Zdenka Šklubalová, Ph.D. Consultant: Sebastien Bailey Student: Brooke Alexandra Dunlap Title of Thesis: The influence of micronized poloxamer on the flow and compaction of a model tableting mixture Lubricants are an important excipient used in the production of tablets, they facilitate powder flow during manipulation, prevent powder sticking to the press during compression, and aid in tablet ejection. In this thesis the effect of four different concentrations 0.5, 1.0, 1.5, and 2.0 % w/w of micronized Poloxamer 188 on a model tableting mixture consisting of a 1:1 ratio of Microcrystalline Cellulose (MCC) and Lactose (L) was tested to determine its effectiveness as a lubricant for tablet manufacturing. Flow through an orifice, angle of repose, Hausner ratio, compressibility index, dynamics of consolidation, and powder bed porosity were tested. There was no increase in flowability of the powder at any concentration of P188 in any test used, all mixtures showed poor or very poor flow behaviour. Compression process was evaluated according to the force displacement method at three different compression forces (5 kN, 7 kN, 10 kN) and special attention was paid to ejection force. P188 is an...
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The influence of micronized poloxamer on the flow and compaction of a model tableting mixture
Dunlap, Brooke Alexandra ; Šklubalová, Zdeňka (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical Technology Supervisor: Assoc. Prof. Zdenka Šklubalová, Ph.D. Consultant: Sebastien Bailey Student: Brooke Alexandra Dunlap Title of Thesis: The influence of micronized poloxamer on the flow and compaction of a model tableting mixture Lubricants are an important excipient used in the production of tablets, they facilitate powder flow during manipulation, prevent powder sticking to the press during compression, and aid in tablet ejection. In this thesis the effect of four different concentrations 0.5, 1.0, 1.5, and 2.0 % w/w of micronized Poloxamer 188 on a model tableting mixture consisting of a 1:1 ratio of Microcrystalline Cellulose (MCC) and Lactose (L) was tested to determine its effectiveness as a lubricant for tablet manufacturing. Flow through an orifice, angle of repose, Hausner ratio, compressibility index, dynamics of consolidation, and powder bed porosity were tested. There was no increase in flowability of the powder at any concentration of P188 in any test used, all mixtures showed poor or very poor flow behaviour. Compression process was evaluated according to the force displacement method at three different compression forces (5 kN, 7 kN, 10 kN) and special attention was paid to ejection force. P188 is an...
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The effect of particle size on lactose compressibility
Havlíková, Natálie ; Ondrejček, Pavel (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical technology Consultant: PharmDr. Pavel Ondrejček, Ph.D. Student: Natálie Havlíková Title of Thesis: The effect of particle size on lactose compressibility It is known that the particle size of the compressed material plays an important role in the manufacture of tablets. It affects the properties of intermediate and final products. In this thesis the properties of tablets made of two lactose types, which were used as model fillers, were studied. These were Tablettose® 80 and Lactopress® Anhydrous. In both lactose types, five sieved size fractions of the particle size ranging from 9 to 346µm and their original unsieved mixture were used. The compaction forces ranging from 2 to 10kN were used for tablet preparation. Magnesium stearate was used for external lubrication. The evaluation of the prepared tablets was done mainly by using the pharmacopoeial methods. The evaluated parameters were friability, disintegration time and hardness. Furthermore, the elasticity of the tablets and the evaluation using the force-displacement method parameters were assessed. From the results of this work, it is not possible to unambiguously determine the advantage of one particular fraction size in the comparison to the...
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Hydromechanic characteristics of clay suspensions
Sedláčková, Markéta ; Mls, Jiří (advisor) ; Císlerová, Milena (referee) ; Šembera, Jan (referee)
A mathematical model of two-phase systems, such as clay suspensions, consists of a set of partial differential equations which reflect both the general laws of mechanics and the relations connecting the involved characteristics of the particular system under consideration. The latter equations are known as constitutive relations. The aim of this study was to find the constitutive relations for kaolin suspensions that are necessary when solving forward problems of fine sludge thickening processes. The task was to design and carry out experimental research of the given suspension and to find a convenient method of utilizing the results for the sake of getting the sought relationships. It follows from the applied mathematical theory of two-phase systems that the sought relationships are hydraulic conductivity of the suspension as a function of the solid-phase concentration and the dependence of the solid-phase concentration on the solid-phase stress. The first part of this study describes the experimental research. Since both the characteristics are difficult to measure, it was necessary to analyze the suspension's characteristics and their measurability. Subsequently, the process of the suspension preparation and the method of laboratory measurements were determined. The following sections present...
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Homogenization of powder blends using a Turbula mixer.
Litošová, Martina ; Šklubalová, Zdeňka (advisor) ; Mužíková, Jitka (referee)
1 Abstract Charles University, Faculty of Pharmacy in Hradci Králové Department of: Department of Pharmaceutical Technology Supervisor: Doc. PharmDr. Zdeňka Šklubalová, Ph. D. Consultant PharmDr. Karel Palát, CSc., Mgr. Žofie Trpělková Student: Martina Litošová Title of Thesis: Homogenization of powder blends using a Turbula mixer. In this experimental work, the influencing of the homogeneity of the powder mixture of acetylsalicylic acid (ASA) and microcrystalline cellulose (Avicel PH102) due to the rotational speed of the mixing container in a range of 23−101 rpm, and the mixing time was studied using the Turbula shaker mixer. Within time interval 2-62 minutes, the content of ASA in samples was measured by near-infrared spectrometry. The expression of standard deviation was used to evaluate the homogeneity of samples. The best results were detected at a rotational speed of 34 rpm within time interval of 14−30 min.
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The study of influence of the measurement method on static angle of repose of free-flowable excipients
Mrázková, Aneta ; Šklubalová, Zdeňka (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical technology Supervisor: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Mgr. Žofie Trpělková Student: Aneta Mrázková Title of Thesis: The study of influence of the measurement method on static angle of repose of free-flowable excipients. Good flow and consolidation properties of powders represent significant characteristics of pharmaceutical excipients They are important for manufacturing of powders into solid dosage forms. Flow behavior of 6 free flowing excipients was evaluated in this diploma thesis. The main target was a study of the influence of the masurement method and the orifice size of a conical hopper on static angle of repose (AOR). The automatic tester and the prototype for measuring AOR having orifice sizes in a range of 6-15 mm were used for the measurement. A significant difference between the results of these two methods (P <0.01) was observed. The decrease in AOR was detected when increased the orifice diameter, the effect was significant (P <0.01) only in automatic tester for two out of six measured powders. Surprisingly, the significant influence of the orifice size on AOR was registered for a sweetener Palatinose with protype equipment.
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The study of influence of the measurement method on static angle of repose of free-flowable excipients
Mrázková, Aneta ; Šklubalová, Zdeňka (advisor) ; Svačinová, Petra (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical technology Supervisor: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Mgr. Žofie Trpělková Student: Aneta Mrázková Title of Thesis: The study of influence of the measurement method on static angle of repose of free-flowable excipients. Good flow and consolidation properties of powders represent significant characteristics of pharmaceutical excipients They are important for manufacturing of powders into solid dosage forms. Flow behavior of 6 free flowing excipients was evaluated in this diploma thesis. The main target was a study of the influence of the masurement method and the orifice size of a conical hopper on static angle of repose (AOR). The automatic tester and the prototype for measuring AOR having orifice sizes in a range of 6-15 mm were used for the measurement. A significant difference between the results of these two methods (P <0.01) was observed. The decrease in AOR was detected when increased the orifice diameter, the effect was significant (P <0.01) only in automatic tester for two out of six measured powders. Surprisingly, the significant influence of the orifice size on AOR was registered for a sweetener Palatinose with protype equipment.
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Laboratory tests of geomechanical properties of Brno clay on reconstituted samples
Rozmánek, Filip ; Koudela, Pavel (referee) ; Chalmovský, Juraj (advisor)
This theses is focused on geomechanical properties of reconstituted Brno clay. The properties of reconstituted soils are different from properties of natural soils because of the ifluence of structure. The properties of reconstituted soils are termed „intrinsic properties“. Object of this theses is to describe these properties and to determine compressibility and strenght charakteristics of Brno clay using reconstituted samples. These charakteristics are obtained using the edometer machine, the triaxial machine and the ring shear apparatus. Calculated data are then compared with known data from literature.
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