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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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The effect of rice extract on the compressibility and mechanical properties of microcrystalline cellulose tablets.
Rumlerová, Lenka ; Ondrejček, Pavel (advisor) ; Mužíková, Jitka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Department of Pharmaceutical Technology Consultant: PharmDr. Pavel Ondrejček, Ph.D Student: Lenka Rumlerová Title of Thesis: The effect of rice extract on the compressibility and mechanical properties of microcrystalline cellulose tablets. This thesis deals with influence of rice extract, as a new kind of glidant on compressibility of microcrystalline celulose as a model filler. Furthermore it evaluates the impact of rice extract on tablet properties. Effects of rice extract were compared with two standard glidants - magnesium stearate and colloidal silicon dioxide. As first the influence of diferent glidants concetrations on flow properties of mixtures were assesed. Tablets were compresed using three different compression forces. A force- displacement record was used to evaluate the compressibility of microcrystalline cellulose and its mixtures with glidants. Subsequently, the properties of tablets were evaluated. The radial strenght, abrasion, and tablet disintegration time were measured. The results revealed that the rice extract has the least effect on mixtures flow poperties. However, all mixtures showed a statistically significant improvement in flowability. When using a 1 % rice extract, the flow properties of the...
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The influence of rice extract as a new lubricant on the compressibility of microcrystalline cellulose
Bučková, Lenka ; Ondrejček, Pavel (advisor) ; Holas, Ondřej (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Department of Pharmaceutical Technology Consultant: PharmDr. Pavel Ondrejček, Ph.D. Student: Lenka Bučková Title of Thesis: The influence of rice extract as a new lubricant on the compressibility of microcrystalline cellulose In this thesis the rice extract was studied as a new lubricant. Primarily its influence on microcrystalline cellulose compressibility was studied. Its effects were compared to sodium stearylfumarate and colloidal silicon dioxide. The used lubricants were wixed with the filler in the concentrations ranging from 0.1 to 1%. The mass flow rate was evaluated in the filler itself and its mixtures. Subsequently, the tablets were made using the compression forces ranging from 2.5 to 7.5kN. The compaction process was evaluated using the force- displacement method. Furthermore, the tablet hardness, friability and disintegration time was tested. The results showed that the rice extract can be used as lubricant for the used model filler. Unlike other evaluated glidants, it must be used at concentrations up to 0,25%. The use of higher concentrations does not improve the flow properties of tableting mixtures. In addition, material elasticity and tablet friability increases and tablet hardness decreases. On the other...
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Compressibility of an intermetallic compound
Staško, Daniel ; Prchal, Jiří (advisor) ; Kaštil, Jiří (referee)
Title: Compressibility of an intermetallic compound Author: Daniel Staško Department: Department of Condensed Matter Physics Supervisor: RNDr. Jiří Prchal, Ph.D., Department of condensed matter physics Abstract: This work focuses on the method of using miniature strain gages for the measurement of volume change and strain in hydrostatic pressure. Two state variables are involved in the changes - temperature and pressure. A copper reference material was used to determine the pressure and temperature corrections for the specific type of strain gage used it this work. To demonstrate this method, a pressure dependence of strain was measured up to 2.3GPa for the CeCuAl3 single crystalline sample along particular crystallographic directions. It is studied for its interesting magnetic properties and this work aims to contribute to its complex study. Temperature dependencies of strain under low and high pressure were also measured. Keywords: high pressure, compressibility, strain gage, CeCuAl3
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Analysis of the factors influencing the geotechnical material parameters of MSW landfills
Sedláček, Václav ; Kudrna, Zdeněk (advisor) ; Slomek, Jiří (referee)
The material of Municipal Solid Waste landfills is a varied mix of materials with different properties. This material changing his properties according the procesing before or after the material is stored in landfill body. While the conditions in the landfill body are suitable, the bacteria start the development of biodegradation process. The process is affected by a number of factors. During the process, a large volume of lanfill gas is released from the landfill body and the landfill surface is declining. Material composition with processing methods during and after the transportation of waste to the landfill create geotechnical parameters of fresh material. As time goes by, this material loses biodegradable ingredients. The biodegradation process takes several years in the space of lanfill body. For the proper process of biodegratation, it's important to compliance next parameters: Sufficient organic matter content, sufficient material moisture and stable temperature with pH. Keywords: Municipal solid waste, geotechnical properties, grain, moisture content, shear strengh, strain, elasticity, deformation, compaction, biodegradation processes
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Analysis of the factors influencing the geotechnical material parameters of MSW landfills
Sedláček, Václav ; Kudrna, Zdeněk (advisor) ; Sedláček, Jaroslav (referee)
Geotechnical parameters of material of Municipal Solid Waste (MSW) landfill are very variable. This work searches by science researches the influences for these parameters. The identification of parameters is obviously difficult and needs special devices capable to measurement of big volume of material. Influence for geotechnical parameters have composing of MWS, climatic conditions, of the MSW landfill is cover or not, if has landfill isolation on base and on top or not or if is landfill drained. Important factor is existence of biodegradation processions on landfill. There are important the velocity of biological component and time.
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Comparision of pick-up balers Claas Rollant 46 Silage and Lely Welger RP 245 at harvest of fodder and straw.
KOCÁBEK, Jan
This thesis is focused on a comparison of round balers from two different producers. The compared balers were Claas Rollant 46 Silage and Lely Welger RP 245. The compared parametrs were the quality of the cutting, compressibility and the quality of forage, The thesis is supplemented by an analysis of performance indicators and exploitation , the cost of pressing and the cost per 1 ton of harvested materiál. For the baler Lely Welger RP 245 the better quality of haylage , more effective compressibility and higher performance were found out. The haylage quality was rated as excellent. Compressibility of hay was 182,27 kg*m-3, haylage 383,31 kg*m-3 and straw 127,64 kg*m-3. Lely Welger RP 245 harvested 12,40 t*h-1 hay, 18,20 t*h-1 haylage and 8,90 t*h-1 straw. Economic indicators were better for Claas Rollant 46 Silage , which was caused by a low purchase cost. The costs per 1 ha were 424,40 CZK*ha-1 for hay, 449,60 CZK*ha-1 for haylage and 410,00 CZK*ha-1 for straw, the costs per 1 ton of harvested material were 120,52 CZK*t -1 for hay, 93,33 CZK*t-1 for haylage and 193.23 CZK*t-1 for straw.
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Volumetric Behaviour of Binary and Ternary Liquid Systems Composed of Toluene, Isooctane and Methyl tert-Butyl Ether at Temperatures from 298.15 K to 328.15 K
Linek, Jan ; Morávková, Lenka ; Wagner, Zdeněk
The densities and speeds of sound of the binary systems toluene plus isooctane, MTBE plus toluene and MTBE plus isooctane and of the ternary system toluene plus isooctane plus MTBE were measured at four temperatures within 298.15 K and 328.15 K, and the respective values of excess volumes EVm and adiabatic compressibility κS were calculated. The EVm and κS values of the binary systems were fitted to the Redlich-Kister equation on applying the weighted gnostic method. The EVm values for the MTBE plus toluene system are negative and decreasing with increasing temperature. The other binary systems show positive EVm with comparatively small temperature dependence. The volumetric data on the binaries and the ternary are of practical importance and besides, serve for testing the correlation procedures for fitting and predicting ternary data from binary ones.
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