In der vorliegenden Arbeit werden M(II)-Formiat-Komplexe mit M=Cu, Ni, Zn beschrieben. Das themogravimetrische Verhalten dieser Komplexe wird vorgestellt. TG-MS-Untersuchungen geben erste Hinweise auf das Metallisierungsverhalten obiger Spezies. Die Charakterisierung der entsprechenden Komplexe erfolgte durch die Elementaranalyse, IR-Spektroskopie sowie in einzelnen Fällen durch die Einkristallröntgendiffraktometrie.

In the present work, there was analyzed thermal evolution of the phase transformation in the MgZnAl and MgZnAlCa alloys with different concentration of the Zn and Ca. The grains were occupied by the phase with quasicrystaline icosaedral structure in the as-cast alloys and after isochronal annealing up to 240 řC. The thermal measurements revealed two exothermic effects in the MgZnAl alloy and three exothermic effects in the MgZnAlCa alloy during linear heat treatment in the temperature range of 100 - 250 řC. In agreement to the thermal response, two and three stages of electrical resistivity decrease were observed in the same temperature range. The lower thermal changes, absolute resistivity changes and microhardness were observed in the alloy with Ca-addition and lower concentration of Zn.

The need for replacing petroleum-based polymers has been increasing and bio-based polymers prove to be a suitable solution. The aim of this thesis was to synthesize bio-based resins with different chemical architectures to evaluate the effect of the structure on the properties and on their response to ageing and biodegradation. For this, three different bio-based thermoset resins have been synthesised by reacting one of three distinct core-molecules with lactic acid. The options of core-molecules chosen for this work were ethylene glycol, glycerol and pentaerythritol. Lactic acid was first reacted with a core-molecule by direct condensation, the resulting branched molecule was then end-functionalized with methacrylic anhydride. The amount of moles of lactic acid varied according to which core-molecule it was reacted with, but the chain length (n) was always maintained as three. Part of the samples were characterised by Fourier-transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and tensile test. DSC and TGA were used for determining the thermal behaviour. FT-IR was used to verify the first and second stage of the reaction and to ascertain the occurrence of the crosslinking reaction. Tensile test was done for investigation of mechanical properties. The ageing and biodegradation tests are useful to ascertain the material possible applications. Therefore, the samples that went through the process of ageing or biodegradation were also characterised in the end of the procedures to further check the effect of those processes on the specimens. The test results indicated that the PENTA/LA cured resin was the most stable thermally. The cured resin’s mechanical properties were similar to each other, so there was no comparison to make in this area. The samples proved to be affected by the biodegradation and the ageing processes, both in visual and structural aspects.

A recent trend in the development of renewable and biodegradable materials has led to the development of composites from renewal sources such as natural fibers. This agricultural activity generates a large amount of waste in the form of peanut shells. The motivation for this research is based on the utilization of peanut shells as a viable source for the manufacture of biocomposites. High-density polyethylene (HDPE) is a plastic largely used in the industry due to its durability, high strength to density ratio, and thermal stability. This research focuses in the mechanical and thermal properties of HDPE/peanut shell composites of different qualities and compositions. The samples obtained were subjected to dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and mechanical tensile strength tests. TO prepare the samples for analysis, the peanut shells were separated into different mesh sizes and then mixed with HDPE at different concentrations. The results showed that samples with fiber size number 10 exhibited superior strength modulus of 1.65 GPa versus results for HDPE alone at 1.32 GPa. The analysis from the previous experiments helped to determine that the fiber size number 10 at 5%wt. ratio in HDPE provides the most optimal mechanical and thermal results. From tensile tests the highest modulus of elasticity of 1.33 GPa was achieved from the samples of peanut shells size number 10 in HDPE at 20%wt. ratio, while the results for HDPE alone were only of 0.8 GPa. The results proved the hypothesis that the addition of peanut shells to HDPE enhances both the thermal and mechanical properties of the composite.

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Author: Alena Podzimková Title of Thesis: Characterization of silicone scar treatment gels Supervisor: PharmDr. Eva Šnejdrová, Ph.D. This diploma thesis deals with characterization of silicone gels by various methods, specifically measurement of rheological properties, overall characterization of the composition by infrared spectroscopy, identification of volatile compounds by gas chromatography and determination of molecular weight distribution of polymers by gel permeation chromatography. The theoretical part provides information about scars and their treatment options and describes the principles and the evaluation of tests performed in the experimental part. Five commercial gels and three newly formulated scar healing gels were evaluated. Analysis of viscosity curves confirmed newtonian type of flow in commercial gels Scar Gel Dr. Max and Stratamed and in the newly formulated gels. Strataderm, RejuvaSil and ScarEsthetique show a decrease in viscosity under stress. Oscillation tests have shown a gel structure only with the commercial ScarEsthetique and RejuvaSil. Scar Gel Dr. Max, Strataderm, the newly formulated gels and Stratamed contain polymeric polydimethylsiloxane. In case of Scar...

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The aim of this work was to assess the suitability of vibrational spectroscopic techniques (Raman, FT-IR and FT-NIR spectroscopy) as a means for the solid-state structural analysis of pharmaceuticals. Budesonide, fluticasone propionate, salbutamol hemisulfate, terbutaline hemisulfate, ipratropium bromide, polymorphic forms of salmeterol xinafoate and two polymorphic forms of sulfathiazole were selected since they are used in the management of certain respiratory disorders and from different chemical and pharmacological entities along with some pharmaceutical excipients. Conventional visual examination is not sufficient to identify and differentiate spectra between different pharmaceuticals. To confirm the assignment of key molecular vibrational band signatures, quantum chemical calculations of the vibrational spectra were employed for better understanding of the first five selected drugs. The nondestructive nature of the vibrational spectroscopic techniques and the success of quantum chemical calculations demonstrated in this work have indeed offered a new dimension for the rapid identification and characterisation of pharmaceuticals and essentially warrant further research. The application of simultaneous in situ Raman spectroscopy and differential scanning calorimetry for the preliminary investigation of the polymorphic transformation of salmeterol xinafoate polymorphs and two polymorphic forms of sulfathiazole has also been explored in this work leading to the development of a new method for the solid-state estimation of the transition temperature of entantiotropically related pharmaceutical polymorphs which represents the first analytical record of the use of this approach for pharmaceutical polymorphs.

Analysis of the molecular speciation of organic compounds in solution is essential for the understanding of ionic complexation. The Raman spectroscopic technique was chosen for this purpose because it allows the identification of compounds in different states and it can give information about the molecular geometry from the analysis of the vibrational spectra. In this research the ionisation steps of relevant pharmaceutical material have been studied by means of potentiometry coupled with Raman spectroscopy; the protonation and deprotonation behaviour of the molecules were studied in different pH regions. The abundance of the different species in the Raman spectra of aqueous salicylic acid, paracetamol, citric acid and salicylaldoxime have been identified, characterised and confirmed by numerical treatment of the observed spectral data using a multiwavelength curve-fitting program. The non-destructive nature of the Raman spectroscopic technique and the success of the application of the multiwavelength curve-fitting program demonstrated in this work have offered a new dimension for the rapid identification and characterisation of pharmaceuticals in solution and have indicated the direction of further research. The work also covers the formation of novel cocrystal systems with pharmaceutically relevant materials. The existence of new cocrystals of salicylic acid-nicotinic acid, DLphenylalanine , 6-hydroxynicotinic acid, and 3,4-dihydroxybenzoic acid with oxalic acid have been identified from stoichiometric mixtures using combined techniques of Raman spectroscopy (dispersive and transmission TRS), X-ray powder diffraction and thermal analysis. Raman spectroscopy has been used to demonstrate a number of important aspects regarding the nature of the molecular interactions in the cocrystal. Cocrystals of II salicylic acid ¿ benzamide, citric acid-paracetamol and citric acid -benzamide have been identified with similar analytical approaches and structurally characterised in detail with single crystal X-ray diffraction. From these studies the high selectivity and direct micro sampling of Raman spectroscopy make it possible to identify spectral contributions from each chemical constituent by a peak wavenumber comparison of single-component spectra (API and guest individually) and the two- component sample material (API/guest), thus allowing a direct assessment of cocrystal formation to be made. Correlation of information from Raman spectra have been made to the X-ray diffraction and thermal analysis results. Transmission Raman Spectroscopy has been applied to the study cocrystals for the first time. Identification of new phases of analysis of the low wavenumber Raman bands is demonstrated to be a key advantage of the TRS technique. / Libyan government and Misurata University

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