Content: The original substance of a book binding provides information about the place of origin, storage and user history of the book, why the preservation of this material in its original form is of crucial importance for research in the field of bookbinding. In a current research project in cooperation with FILK Freiberg, a newly sustainable treatment for historical aged leather book covers will be developed. The aim is to introduce a long-term mild care agent to boost leather flexibility, which will remain in the structure and to stabilize the pH value at the optimal level with the buffer introduced in the form of deacidification agent. Preliminary research showed, that ageing processes of vegetable tanned calf leather, which has been mainly used for leather book bindings in the past centuries, haven’t been fully explored yet. Further, essential characterization methods like the determination of the acid content and methods for accelerated aging tests are not yet defined for leather. For a systematic development and evaluation of the newly treatment, the project had to be focused on these topics first. Oxidation and acid-catalyzed hydrolysis have an enormous impact on the state of the leather. Both take place simultaneously and affect each other. It could be shown that the damage by acid hydrolysis is much more dominant than the damage by oxidation. Since oxidation plays only a minor role and can be slowed down only preventively by storage conditions, the project focused on the hydrolysis as the significant degradation mechanism. The aim of accelerated ageing was to reproduce as precisely as possible observed and identified degradation mechanisms in the natural aged leather. Therefore, a two-step aging process has been developed. The first stage is to introduce the acid into the material that is to be used to simulate the acid catalyzed hydrolytic degradation. The second step is to verify the effectiveness of the newly developed care products by comparing treated and untreated leathers at this stage of aging. The aging was evaluated by optical / haptic tests, shrinking temperature, mechanical properties, hot water solubility, pH value and differential number. Regarding the leather characterization, the determination of the exact amount of acid introduced by the artificial aging is of great importance for the development of the aging method as well as for the pH adjustment of the leather. For the method development, an acid-base titration was selected, which allows quantitative results of the acid content in the examined material. The developed method is easy to carry out and allows the measurements of different sample quantities (0,1 g - 1,0 g). Take-Away: - acid-catalyzed hydrolysis is the dominant degradation mechanism, oxidation plays a minor role - acid-base tritration allows quantitative results of the acid content in the examined material - development of an accelerated ageing method

This research explores Isothermal Titration Calorimetry as a method for measuring beta-galactosidase activity directly and continuously in milk, sweet whey, sweet whey permeate, acid whey, and acid whey permeate. Beta-galactosidase in various concentrations was injected into each of the liquid dairy products spiked with lactose to verify if the heat rate from the enzymatic reaction could be observed. In addition, a consistent concentration of beta-galactosidase was injected into various concentrations of lactose in the products, to observe the heat rates from the enzymatic reaction. There was exothermic activity that never returned to baseline demonstrated in milk, sweet whey, and sweet whey permeate with beta-galactosidase from Kluyveromyces lactis in runs done in the isothermal titration calorimeter. The baseline was approximately 3-9 uJ/s above the control's baseline at the end of the runs. The exothermic activity ranged from approximately 2-10 uJ/s and did not return to baseline when beta-galactosidase concentrations were varied and lactose concentrations remained the same. The exothermic heat rate was approximately 3-7 uJ/s when lactose concentrations were varied and enzyme concentrations remained the same. With runs with increasing lactose concentrations, there was no corresponding increase in the exothermal reaction indicating saturation of the enzyme. There was a short exothermic reaction(s), ranging from approximately 3-26 uJ/s, demonstrated when varying concentrations of beta-galactosidase from Aspergillus oryzae in acid whey and acid whey permeate were injected into a consistent concentration of lactose in acid whey and acid whey permeate. There was a pattern of increasing heat with increasing concentrations of enzyme, with some of these differences being statistically significant. There was also a short exothermic reaction(s), ranging from approximately 2-17 uJ/s, demonstrated when a consistent concentration of beta-galactosidase from Aspergillus oryzae was injected into varying concentrations of lactose. There was a pattern of increasing heat rate with increasing concentrations of lactose, with some of these differences being statistically significant. This research demonstrates that ITC is a useful method for measuring residual beta-galactosidase and/or residual lactose in liquid dairy products. This research leads to further understanding of how enzymes and substrates interact directly in the food matrix, rather than in an isolated environment.

The thesis deals with the quality of water in general as well as from the perspective of water pollution, wastewater and its treatment within the context of electrotechnical production. The thesis is based on the laboratory task in the practical part, which has been included in the Ecology of Production class. The laboratory task tests the selected indicators of water quality using titration and rapid tests. The thesis is based on the wastewater operation of a company producing PCB.

This diploma thesis deals with the monitoring of chemical changes in ground coffee stored in various containers and then it deals with the determination of water, moisture and aromatic profile of coffee in individual containers, namely a can, a paper bag, a bag with a polyethylene liner, a bag from low density polyethylene with aluminium liner (LDPE + Al) and a glass container. At the beginning of the experiment it was found that the water content in the coffee was 4.72 ± 0.10 % and the moisture content was 9.47 ± 0.01 %. After the original sample was measured, the coffee was poured into 5 packages. At the end of the experiment, a can was chosen as the most suitable package where the lowest water content was measured. The water content was determined to be 6.51 ± 0.11 % and the moisture content was 9.93 ± 0.01 %. However, the differences between the other packages, apart from the paper bag, were very small, and thus in general it can be said that the can, the LDPE + Al package, the bag with the PE liner and the glass container are suitable for storing ground coffee. A total of 44 aromatics were identified when determining the aromatic profile in coffee by HS-SPME-GC-MS. The most represented groups of substances were furans and pyrazines. During storage, there was some loss of substances due to 2 mechanisms. The first of them is evaporation and the second one is the oxidation reactions themselves. Most aromatic substances have evaporated / degraded in paper packaging, where this large decrease is related to its barrier properties. A glass container was chosen as the most suitable packaging with the least loss of aromatic substances.

The aim of this diploma thesis is to study to the influence of compost addition to soil humic substances extracted from blackland luvicsol. Humic substances extracted from soil and from compost were characterized by titration with potentiometrical and conductival indication, UV-VIS, FT-IR and 3D EEM fluorescential spectroscopy. Compost in amount of 124, 239 and 478 t/ha was applicated and manured into dept of 150 mm at blackland luvicsol. The main aim of thesis was the appraisal of compost influence into fluorescent attributes of soil HS and localization of fluorescent peaks at excitation emission spectrums. Next part of diploma thesis was focused on the study of spectroscopic attributes of soil HS and compost by UV-VIS and infrared spectroscopy with Fourier transformation. Humic substances were characterized by humifical index E4/E6 and transmissional vibratile spectrums. The last aim of diploma thesis were the characterization of soil HS extracts and compost by acidimetral titration. For each sample was calculated value of H+ ionts amount of substance from measured titrational curves.

“Green” explosives are an important sub-family of explosives due to the banning of explosives based on heavy metals, such as lead azide and lead styphnate, according to the REACH list. A substitute to lead azide is potassium 4,6-dinitrobenzofuroxane (KDNBF) which is an alternative “green” explosive. Hence there is an upcoming need for analytical and quality control protocols for KDNBF. In this report is HPLC-UV/VIS, GC-FID and potentiometric titration evaluated for their suitability as methods for testing of KDNBF. The results implies that KDNBF can be analyzed by GC-FID, when dissolved in DMSO and caffeine is used as internal standard. To analyze KDNBF by HPLC-UV/VIS was isocratic mode used together with a porous graphitic carbon (PGC) (Hypercarb ®) column. However, degradation of the analyte was severe and quantitative results were not obtained. Potentiometric titration indicated that KDNBF equilibrate with four hydrogen ions during titration, instead of the one to one ratio with potassium and hydrogen ion, as in previously proposed theory. Despite this and with careful titration is potentiometric titration and GC-FID analysis combined suitable as a quality control protocol for KDNBF.

The actual life of a transformer is determined by ageing of the cellulosic insulation such as transformer paper. The presence of moisture in the insulation system decreases the electrical strength of paper and accelerates the aging. It is an efficient way to monitor the moisture content in paper insulation by measuring the dielectric constant of the paper. The moisture dependent permittivity of impregnated transformer paper below 1 MHz has been widely investigated. High frequency (> 1 MHz) dielectric spectroscopy is under requirement since the loss peak information is missing. The impregnated paper is kept in desiccators with saturated salt solutions to get the samples with moisture content from 1 % to 5.5 %. Then they are placed in a coaxial line and the scattering parameters are obtained by modern Vector Network Analyzer. Full wave analysis is utilized to calculate the permittivity from the obtained S-parameters due to its high accuracy. The magnitude of the dielectric spectroscopy below 100 Hz is very dependent on the moisture content while there is a horizontal shift of curves towards higher frequencies depending on the water content over a wide frequency range. The loss peaks appear between 1 MHz and 1 GHz for the impregnated paper with moisture level less than 5.5 %. Due to the limited system accuracy, there is a blank frequency band from 1 MHz to 100 MHz.

Zinc is an essential metal ion for the activity of multiple enzymes and transcription factors. Among many other transporting proteins human serum albumin (HSA) is the main carrier of Zn(II) in the blood plasma. HSA displays multiple ligand binding sites with extraordinary binding capacity for a wide range of ions and molecules including fatty acids. Hence, HSA controls the availability and distribution of those molecules throughout the body. Previous studies have established that the existence of one zinc site with high affinity (MBS-A) that is modulated by the presence of fatty acids. Therefore, the fatty acid concentration in the blood influences zinc distribution which may result in a significant effect on both normal physiological processes and a range of diseases. Based on the current knowledge of HSA's structure and its coordination chemistry with zinc ion, here, we attempted to investigate zinc interactions and coordination with HSA and the effect of different fatty acids on the protein structure, stability and on Zn(II) binding. By NMR titration, we examine the Zn(II) binding to HSA and the spectra show distinct movements of some resonances showing a conformational change has occurred as a result of Zn(II) binding. Isothermal calorimetry titrations study was performed to evaluate zinc binding affinity to HSA in the absence and presence of fatty acids. Free HSA results indicates the existence of one high affinity site and multiple low affinity sites. Upon the binding of fatty acids to HSA, three distinct behaviors of Zn(II) affinity was observed ranging from no effect to moderate to significant depending on the FAs. By the use of circular dichroism, we investigate secondary and tertiary structure of HSA in the presence and absence of FAs and Zn(II). We found albumin is predominately α-helical and the overall conformation of the protein remains unchanged even after interacting with FAs and Zn(II) with some exception. The structural stability of HSA was evaluated by obtaining the denaturation temperature in the presence and absence of fatty acid and we found the thermal denaturation of HSA increases with the increase of amount of fatty acids.

In dieser Dissertation wird beschrieben, wie es durch systematische Anwendung unterschiedlicher Methoden zur Herstellung und Modifizierung von Diamant gezielt und verlässlich möglich ist, die Eigenschaften von Diamanten zu beeinflussen. Es wird gezeigt, wie durch Variation der Parameter bei dem Wachstum von Diamant Einfluss auf dessen Morphologie und Eigenschaften genommen werden kann. Des Weiteren wird ein Verfahren vorgestellt, mit dem die Oberfläche des Diamanten durch Ozon effizient oxidiert beziehungsweise reduziert werden kann. Um diese veränderte Oberflächenbelegung möglichst genau zu analysieren, wird im letzten Teil der Dissertation eine Methode zur qualitativen und quantitativen Analytik der Oberflächen von Kohlenstoffnanomaterialien beschrieben. / This dissertation describes how it is possible to alter the properties of diamond utilizing varying methods for diamond growth and surface modification. It is shown, how by varying the parameters during the growth of diamond, influence can be exerted on its morphology and properties. Furthermore, a procedure is described to efficiently oxidize or reduce the surface of diamond using ozone. In order to analyze this modified surface as precisely as possible, a method for qualitative and quantitative analysis suitable for carbon nanomaterials is presented.

The dairy industry uses enzymes to make cheese, alter product flavor, and eliminate lactose. The activities of these enzymes have been measured in clear buffered solutions, but because of the limitations of spectrophotometric methods, enzyme activities have not been measured in opaque or colored dairy products where they are used. Isothermal titration calorimetry (ITC) can be used to determine reaction kinetics in opaque and colored solutions by measuring the heat rate from enzyme-catalyzed reactions as a function of time. This study used ITC to measure β-galactosidase activity in opaque solutions of milk, sweet whey, sweet whey permeate, acid whey, and acid whey permeate with two β-galactosidase (EC 3.2.1.23) isozymes derived from A. oryzae and K. lactis. The components of the dairy fluids alter the enzyme kinetics and reaction thermodynamics, and the reactions catalyzed by the two homologs differ as shown by differing thermodynamic profiles. The study demonstrates that ITC can be used to measure enzyme activity in opaque and colored dairy fluids and identify reactions by their thermodynamic properties. To ensure that ITCs are accurately recording heat data they must be calibrated regularly. However, potential problems have been identified with standard electrical calibration procedures; primarily being that the calibration is performed outside of the sample cell. This implies that any loss of heat from the theoretically adiabatic sample cell or loss of signal through led wires would be ignored by the electrical calibration. This research describes a new means for the chemical calibration of ITCs by performing acid-base titrations into the sample cell with KHP and TRIS base. This method for reaction was shown to be accurate to theoretical values across multiple temperatures and with different models of ITCs. Measurement errors due to diffusion of substrate are described along with means for limiting this factor. The method identified provides a procedure for maintaining the accuracy of ITCs by comparing their data to well-known thermodynamic values. It is anticipated that the simplicity and low-cost for running this calibration method will further standardize ITCs, help establish the ITC as a reliable method for measuring enzyme kinetics, and will make their maintenance simple enough for their use in quality assurance and industry settings.