Pitches are important precursors for carbon materials. They are usually obtained by thermal treatment of petroleum and coal fractions. Pitches have higher carbon content and are capable of developing into graphitisable carbons upon heat treatment. Petroleum pitches are generally less aromatic than coal tar pitches. Medium-temperature gasifier pitch (MTP), from Sasol’s Lurgi process, is a potential precursor for graphitisable carbon. MTP showed a high degree of solubility in several organic solvents, namely dimethylformamide, quinoline, tetrahydrofuran, pyridine, morpholine, benzene, toluene, xylene and acetone. It was virtually insoluble in n-hexane, cyclohexane, cyclohexanol, acetonitrile and formamide. MTP pitch was partially soluble in methanol and had a solubility limit of 40 g/l at ambient temperature. MTP samples were spiked with boron to make 1000 ppm B-containing samples. The boron distribution coefficient was defined as the ratio of the boron contents of the insoluble pitch residue to the methanol-soluble pitch extracts, using a mass balance. This justified the decision to define the apparent boron partition coefficients based on the boron content of the recovered pitch residues. 4-(dibenzofuranyl) boronic acid (DBA), 2 phenoxyphenyl boronic acid (PBA), p-tolylboronic acid (TBA) and phenylboronic acid (PLA) were retained the most in the residues after methanol extraction. Over 500 ppm of PBA, TBA and PLA were retained in the pitch residues following methanol extraction. The results showed that methanol extracted substituted boron acid model compounds. Methanol dissolved mostly low molecular mass/aliphatic species, which are not important for graphitisation. The thermomechanical analysis (TMA) results showed that MTP has a low softening point compared with the methanol-insoluble (MI) fractions. The attenuated total reflectance (ATR) results showed that the benzene-insoluble (BI), toluene-insoluble (TI) and MI fractions had more intense aromatic C–H stretching peaks than their corresponding soluble fractions. Elemental analysis and the solid-state 13C nuclear magnetic resonance (NMR) results revealed that the benzene-, toluene- and methanol-insoluble fractions are more aromatic than their corresponding soluble fractions. The order of the aromaticity index for the insoluble fractions was as follows: MTP<MI<TI<BI. Matrix-assisted laser desorption (MALDI) analysis of the mass distribution revealed that the majority of compounds in MTP and its soluble and insoluble fractions were in the low molecular mass range, i.e. 190–388 atomic mass units. The thermal analysis results showed that the benzene-, toluene- and methanol-insoluble fractions were thermally stable and had higher carbon yields than their corresponding soluble fractions. MTP was thermally more stable than the methanol-, toluene- and benzene-soluble fractions. Evaluation of the polycyclic aromatic hydrocarbons (PAHs) by gas chromatography-mass spectrometry (GC-MS) showed that the methanol-insoluble fractions had lower PAH contents than MTP and MI.   Copyright / Dissertation (MSc)--University of Pretoria, 2012. / Chemistry / unrestricted

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Thesis (Ed.D.)--Boston University. / The problem of this study was to provide from objective pitch measurements an answer to the question: What does a child do with his vocal pitch in certain speaking and oral reading activities? The purposes of the study were: 1, To locate in terms of fundamental frequencies the average pitch levels used by children in speaking, in easy and difficult reading, and in unaided recall of easy and difficult reading. 2. To compare the mean vocal pitches of the five oral activities noted above. 3. To report average pitch levels significantly related to differences in sex, intelligence, grade placement, and educational achievement for the groups studied.

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Thirty trials of each of three roughness conditions were examined. The first condition consisted of a baseball pitched so that two of the roughness elements opposed the flow. The second condition consisted of a pitched baseball with four of the roughness elements opposing the flow. The third consisted of a pitched uniformly rough sphere. The conclusions were that roughness elements increase horizontal flight deviations when a baseball rotates about a vertical axis; roughness elements on the surface of a baseball may cause a decrease in the encountered drag forces; linear velocity has a dominating effect on the trajectory of a spinning baseball; previously developed mathematical models do not adequately predict flight deviations.

Diploma thesis is focused on design of the road bridge across the river Moravská Dyje, close the village Stare Hobzí. The are designed 3 studies of the bridge, of wich the trapezoidal slabroad with pitches is chosen for further development. Slabroad is assessed at ultimate limit state and serviceability by the valid standarts. Calculation of internal forces is made by computer program Scia Engineer 16.0.

The main aim of my thesis is to create sustainable local food production in Jaroslavice region. This region is situated near the Austria – Czechia border. The political changes of previous century influenced this rural location a lot. Changes resulted in socioeconomic degradation of this area. My project tends to shorten production connections between producers and consumers. It also takes the part with local farmers and farmer´s market. My architecture proposal is a building of regional food center focused on fruit production. The main fruits are apples, apricots and pitches according to the local climate conditions. The center has three main parts – processing, storage and retail.