Made available in DSpace on 2014-12-17T14:52:41Z (GMT). No. of bitstreams: 1 ThaziaVSS.pdf: 623176 bytes, checksum: f3522bf5126d51241ee4b1cc03a0a3ad (MD5) Previous issue date: 2008-11-17 / This thesis intends to show the level of pollutant emissions in the State of Rio Grande do Norte, generated by the final consumption of energy in the many different sectors of the economy. This information was obtained from the energetic matrix and from the pollutant emissions of the State and the data was taken from the Balan?o Energ?tico Estadual and from the Sistema de Informa??es Energ?ticas da Olade. The result will permit to identify the energy and most polluting economic sectors in Rio Grande do Norte, contributing to energy planning, giving direction to the public policy development that aim at the change of the energy matrix of the State. Also with the objective of reducing pollutant emissions through rationalization, efficiency and energy substitution, which the main objective is to promote the economic development based on energy consumption of less harmful impact on the environment, contributing to establishment of sustainable development / A disserta??o pretende apresentar o n?vel de emiss?es em que se encontra o Estado do Rio Grande do Norte, geradas com o consumo final de energ?ticos nos diversos setores da economia. Esta informa??o foi obtida a partir da matriz energ?tica e de emiss?es poluentes do Estado, cujos dados foram extra?dos do Balan?o Energ?tico Estadual e do Sistema de Informa??es Energ?ticas da Olade. O resultado poder? identificar os energ?ticos e os setores econ?micos mais poluidores do RN, podendo auxiliar o planejamento energ?tico, direcionando o desenvolvimento de pol?ticas p?blicas que visam altera??o gradativamente da matriz energ?tica do RN com vistas ? redu??o de emiss?es poluentes atrav?s da racionaliza??o, efici?ncia e substitui??o energ?tica, cujo objetivo ? promover o desenvolvimento econ?mico, pautado no consumo de energia, de forma menos danosa ao meio ambiente, contribuindo tamb?m para o alcance de um desenvolvimento sustent?vel

The Master’s Thesis deals with project management issues in the field of energetic, specifically diversification of fuel base with usage of renewable resources. The thesis is divided into two parts, from which the first part is focused on theoretical background of project, project management and feasibility study issues. In the second part particular feasibility study is elaborated. The goal of this thesis is to create feasibility study, which is one of the requested appendixes of grant application.

Modern production systems have to allow high performance cutting processes in a flexible production system environment at a high level of accuracy. The final workpiece accuracy is mainly influenced by the thermo-elastic behavior of the machine tool and can be improved by additional measures, compensation strategies and an optimized machine design. These measures are often implemented as stand-alone solutions. According to the Industry 4.0 all information should be connected in a single model of the actual machine state to increase machining accuracy. It is therefore necessary to integrate upcoming smart fluid power systems into the machine network.

Due to good energy-efficiency of electrohydraulic compact drives a cooling aggregate often is not installed. The operating temperature is governed by the complex interaction between dissipative heat input and passive heat output. This paper targets the simulation of the thermo-energetic behaviour of an electrohydraulic compact drive by means of a lumped parameter model in order to predict the operating temperature. The developed thermo-hydraulic model is validated against measurements utilising thermocouples and a thermographic camera to capture temperatures. The results show, that the presented methodology enables a satisfying accurate prediction of the thermo-energetic behaviour of electrohydraulic compact drives. A further analysis of simulation results is given, highlighting the power losses and heat rejection capabilities of different components. Finally, measures for the improvement of the heat rejection capabilities are studied.

Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The abundance and diversity of carbohydrate and protein resources in the southern Cape of South Africa may well have aided the survival of modern humans through the harsh climatic conditions of the late Pleistocene. Until now, the carbohydrate resources, in particular the underground storage organs (USOs) of some plant species have not been described from a forager’s perspective. This is baffling when one considers that the Cape Floristic Region of South Africa harbors the highest diversity of geophyte (herbaceous plants which possess USOs) species in the world. I report on USO distribution and abundance in the southern Cape of South Africa and on the effort, nutritional return and energetic return rates of harvesting these USOs. To determine their distribution and abundance, I assessed identity and abundance in a hundred 25m2 plots. These data, along with biomass data of every species sampled, allowed me to quantify the variation of this potential food source over different habitat types in the southern Cape landscape. Furthermore, I observed the time it took for human subjects to gather a sample of six USO species in three different vegetation types and in two seasons. Proximal analyses of the nutritional content of each of these species provided data which, when combined with foraging time, enabled a basic quantification of the return rate of energy (in calories) per time unit. There is high variability in the distribution of edible USO abundance and biomass across the study area, with some sites having very high biomass. Such biomass hotspots are likely to have been targeted by foragers, returning biomass values comparable to other studies which have been conducted on extant hunter-gatherer communities. Due to considerable variation over the landscape, the hotspots of biomass did not correlate significantly with any abiotic variables we measured. This suggests that hotspots of high biomass may have been challenging to find, unless the cognitive skills required to locate such patches were sufficiently developed – certainly excellent knowledge of the landscape and botany would have been crucial if survival depended on locating these diet items. USO species belonging to the Iridaceae family had the highest overall and average biomass in the area, so it is not surprising that this family is best represented amongst USO plant remains found in the archaeological record. Little effort (time) was required to obtain the six species of USOs we observed, although the weights obtained were also low. The nutritional returns of the six test species were higher than in other studies. The return rates per simulated foraging event in this study therefore compare favorably to the anthropological observations of extant hunter-gatherer communities. The lines of evidence presented in this thesis therefore lend support to the hypothesis that the USO resources of the southern Cape would have provided a large component of the carbohydrate requirements for sustaining hunter-gatherer communities. The data set presented in this thesis can be considered a baseline for future studies. / AFRIKAANSE OPSOMMING: Die digtheid en diversiteit van koolhidraat- en proteïenhulpbronne in die Suid-Kaap van Suid-Afrika mag die oorlewing van die moderne mens beïnvloed het tydens die ongunstige klimaatstoestande wat geheers het deur die laat Pleistoseen. Tot op hede is die koolhidraathulpbronne in die area nie beskryf vanuit ‘n kosversamelaar se perspektief af nie, spesifiek nie die koolhidrate wat deur ondergrondse stoororgane (OSO's) van sommige plantspesies verskaf kan word nie. Dié feit is verstommend as mens in ag neem dat die Kaapse Floristiese Streek van Suid-Afrika die hoogste geofietspesies (kruidagtige plante met OSO's) diversiteit ter wêreld het. Ek rapporteer oor die verspreiding en digtheid van OSO's in die Suid-Kaap en op die inspanning, voedingswaarde en energie-opbrengskoerse verbonde aan die oes van dié OSO's. Verspreiding en digtheid is bepaal oor ʼn honderd 25m2 plotte. Dié data, saam met die biomassa-data van elke spesie wat geïdentifiseer was, is gebruik om potensiële voedselbronne te kwantifiseer in verskillende habitattipes in die Suid-Kaap. Ek het verder die tyd wat dit neem vir mense om die ses geïdentifiseerde OSO-spesies te oes in drie verskillende habitatte en twee seisoene waargeneem. Voedingswaarde-data, tesame met OSO-oestyd-data, is gebruik vir die basiese berekening van energie-opbrengskoerse van spesies deur middel van proksimale analises. Daar is hoë variasie in die verspreiding, digtheid en biomassa van eetbare OSO's gevind in die studie-area, met sommige plotte wat baie hoë biomassa bevat het. Hierdie areas van hoë biomassa sou heel waarskynlik deur kos-versamelaars geteiken gewees het, en gevolglik hoë opbrengste van biomassa bied, wat vergelykbaar is met die biomassa-waardes wat waargeneem word binne areas waar huidige jagter-versamelaar-gemeenskappe tans oorleef. As gevolg van die aansienlike variasie wat waargeneem is oor die landskap het die hoë-biomassa-areas nie beduidend gekorreleer met enige abiotiese veranderlikes wat gemeet is nie. Dit dui daarop dat hoë-biomassa-areas moeilik kan wees om te vind, tensy kognitiewe vermoëns wat noodsaaklik is om kolle van hoë biomassa te vind ontwikkel was. OSO-spesies wat aan die Iridaceae-familie behoort het die hoogste algehele en gemiddelde biomassa in die area gehad. Dit is dus nie verbasend dat dié familie die beste verteenwoordig word in die argeologiese rekord van OSO-plantoorskot nie. Min inspanning (tyd) was nodig om die OSO's van die ses geïdentifiseerde spesies te bekom, alhoewel die massa wat bekom is ook laag was. Die voedingswaarde-opbrengs (per eenheidsmassa) van die ses toetsspesies was hoër as in ander studies. Die energie-opbrengskoers per versamelingsgebeurtenis het gevolglik ook gunstig vergelyk met die antropologiese waarnemings wat van huidige jagter-versamelaars gemeenskappe gemaak is. Die resultate van hierdie studie ondersteun die hipotese dat die OSO-hulpbronne in die Suid-Kaap 'n groot komponent van die koolhidraat-vereistes van jagter-versamelaar-gemeenskappe sou gewees het. Die datastel wat in dié tesis aangebied word kan as 'n basisverwysing dien vir toekomstige studies.

Turbulent magnetic fields are ubiquitous in space physics and astrophysics. The influence of magnetic turbulence on the motions of charged particles contains the essential physics of the transport and acceleration of energetic charged particles in the heliosphere, which is to be explored in this thesis. After a brief introduction on the energetic charged particles and magnetic fields in the heliosphere, the rest of this dissertation focuses on three specific topics: 1. the transport of energetic charged particles in the inner heliosphere, 2. the acceleration of ions at collisionless shocks, and 3. the acceleration of electrons at collisionless shocks. We utilize various numerical techniques to study these topics. In Chapter 2 we study the propagation of charged particles in turbulent magnetic fields similar to the propagation of solar energetic particles in the inner heliosphere. The trajectories of energetic charged particles in the turbulent magnetic field are numerically integrated. The turbulence model includes a Kolmogorov-like magnetic field power spectrum containing a broad range of scales from those that lead to large-scale field-line random walk to small scales leading to resonant pitch-angle scattering of energetic particles. We show that small-scale variations in particle intensities (the so-called "dropouts") and velocity dispersions observed by spacecraft can be reproduced using this method. Our study gives a new constraint on the error of "onset analysis", which is a technique commonly used to infer information about the initial release of energetic particles. We also find that the dropouts are rarely produced in the simulations using the so-called "two-component" magnetic turbulence model (Matthaeus et al., 1990). The result questions the validity of this model in studying particle transport. In the first part of Chapter 3 we study the acceleration of ions in the existence of turbulent magnetic fields. We use 3-D self-consistent hybrid simulations (kinetic ions and fluid electrons) to investigate the acceleration of low-energy particles (often termed as "injection problem") at parallel shocks. We find that the accelerated particles always gain the first amount of energy by reflection and acceleration at the shock layer. The protons can move off their original field lines in the 3-D electric and magnetic fields. The results are consistent with the acceleration mechanism found in previous 1-D and 2-D simulations. In the second part of Chapter 3, we use a stochastic integration method to study diffusive shock acceleration in the existence of large-scale magnetic variations. We show that the 1-D steady state solution of diffusive shock acceleration can be significantly modified in this situation. The results suggest that the observations of anomalous cosmic rays by Voyager spacecraft can be explained by a 2-D shock that includes the large-scale magnetic field variations. In Chapter 4 we study electron acceleration at a shock passing into a turbulent magnetic field by using a combination of hybrid simulations and test-particle electron simulations. We find that the acceleration of electrons is greatly enhanced by including the effect of large-scale magnetic turbulence. Since the electrons mainly follow along the magnetic lines of force, the large-scale braiding of field lines in space allows the fast-moving electrons interacting with the shock front multiple times. Ripples in the shock front occurring at various scales also contribute to the acceleration by mirroring the electrons. Our calculation shows that this process favors electron acceleration at perpendicular shocks. We discuss the application of this process in interplanetary shocks and flare termination shocks. We also discuss the implication of this study to solar energetic particles (SEPs) by comparing the acceleration of electrons with that of protons. The intensity correlation of electrons and ions in SEP events indicates that perpendicular or quasi-perpendicular shocks play an important role in accelerating charged particles. In Chapter 5 we summarize the results of this thesis and discuss possible future work.

On account of the high temperatures and pressures experienced by energetic materials during deflagration and detonation, it is important to know not only the physical properties of these materials at ambient temperatures and pressures, but also to understand how their structure and properties are affected by extreme conditions. Combined computational and experimental investigations of the effects of high pressures on the structure and properties of several energetic materials are described herein. A comparison of the performances of different pseudopotentials and density functional theory (DFT) dispersion correction schemes in calculating crystal geometries and vibrational frequencies of crystalline ammonium perchlorate at high pressure is described. The results highlight the fact that care must be taken when choosing pseudopotentials for high-pressure studies. A comprehensive comparison of calculated vibrational modes (including symmetry) with experiment has been performed, with the frequencies of all internal modes predicted to lie within 5% of experimental values. This study established that no significant improvements in the calculation of crystal geometries of ammonium perchlorate are obtained by employing DFT-D corrections. The enthalpy of fusion (ΔHfus) of the highly metastable β-form of RDX (cyclotrimethylenetrinitramine) was determined to be 12.63 ± 0.28 kJ mol-1. DFT-D calculations of the lattice energies of the α- and β-forms of RDX are described. Furthermore, the response of the lattice parameters and unit-cell volumes to pressure for the α-, γ- and ε-forms of RDX calculated using DFT-D are in very good agreement with experimental data. Phonon calculations provide good agreement with vibrational frequencies obtained from Raman spectroscopy, and a predicted inelastic neutron scattering (INS) spectrum of α-RDX shows excellent agreement with experimental INS data recorded as part of this study. The results of the high-pressure phonon calculations have been used to show that the heat capacities of the α-, γ- and ε- forms of RDX are only weakly affected by pressure. DFT-D calculations have been utilised to describe accurately the structure and properties of both β-HMX (Cyclotetramethylenetetranitramine) and α-FOX-7 (1,1-Diamino-2,2-dinitroethylene) as a function of pressure. This work presents data for the experimental hydrostatic compression of both deuterated β-HMX and α-FOX-7 performed using neutron powder diffraction at the ISIS Neutron and Muon facility, in addition to experimental determinations of the INS spectra of both β-HMX and α-FOX-7. The DFT-D hydrostatic compression studies for both materials reproduce the experimental compression trends. Furthermore, the calculated vibrational properties as a function of pressure were in very good agreement with available experimental data. The results of the phonon calculations were then used to predict the effect of pressure on the heat capacities of β-HMX and α-FOX-7. These predictions suggest a very weak pressure dependence of heat capacities (approximately -1 J K-1 mol-1 GPa-1) for these materials. This work demonstrates that the DFT-D model performs extremely well over a range of conditions, and is able to describe accurately intramolecular and intermolecular interactions, and thus the structure and properties of organic molecular nitramine crystals. The computational model was therefore used to predict the high-pressure hydrostatic compression behaviour of a related nitramine, CL-20 (2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane), the results of which highlighted possible discrepancies in the experimental high-pressure X-ray diffraction data recorded for ε-CL-20. This prompted a high-pressure neutron powder diffraction study, which showed good agreement with the computational results, thereby highlighting radiation damage in the X-ray experiments.

Energetic materials encompass a wide range of chemical compounds all associated with a significant risk of fire and explosion. They include explosives, fireworks, pyrotechnics, powders, propellants and other unsteady chemicals. These materials store a high level of chemical energy and are able to release it rapidly without external contribution of oxygen or any other oxidizer. The behaviour of these materials in case of explosive detonations is relatively wellknown from empirical and practical points of view. However, fundamental scientific questions remain unanswered related to the mechanisms of heat release. The current understanding of these mechanisms lacks appropriate thermochemical characterisation. The aim of the study is the analysis of thermal and chemical characteristics of energetic materials under conditions that exclude detonations. Detonation is excluded in order to better isolate the thermal and chemical mechanisms involved in the burning process. The experimental work has been conducted using the FM Global Fire Propagation Apparatus (FPA) [ASTM E2058‐03]. One of the benefits of using this experimental apparatus rather than the Cone Calorimeter is that it allows controlling the feed of heat and oxidizer to the reaction zone. The material chosen to conduct experiments on is a ternary smoke powder based on a mixture of starch and lactose as fuel components and potassium nitrate as oxidizer. This product is currently used by fire brigades to assess smoke venting systems efficiency of buildings. The kinetics associated with the combustion of the material was assessed slow enough to allow measuring instruments to capture the thermal and chemical evolution during combustion reaction. Thermal analysis has first been carried out by means of DSC, TGA, DTA, MS and FTIR data in order to understand the decomposition of the material and its energetic evolution when undergoing heating. However, if the latter methods help defining the decomposing path of the material, they do not provide an integral view of its combustion behaviour, in particular, the emissions of toxics which are kinetic path dependent. Subsequently, combustion tests have been carried out using the FPA. Its ability to capture the evolution of gases emissions formed during the reaction has been proved. The influence of two configuration parameters on the combustion behaviour and on the gaseous emissions of the material has been investigated. The proportion fuel/oxidizer has been varied as well as the composition of the reacting atmosphere. Results shows that the quantity of oxidizer in the material affects the kinetics of the reactions taking place in the condense phase. Increasing the concentration of potassium nitrate in the mixture enhanced the reaction rate of the smouldering combustion. Higher quantity of volatiles is released which favoured the initiation of a diffusion flame regime in the gaseous phase, above the sample. While the kinetics of the condense phase is governed by the oxidizer concentration, experiments show that the flaming regime is influenced by the concentration of oxygen (O2) in the reacting atmosphere. A transition from diffusion to premixed flame is found when the concentration of O2 surrounding the sample is reduced below 18%. An analytical model has been used to explain the existence of a transition for a critical O2 concentration. Finally, thermal and combustion analyses have allowed to characterise the behaviour of the material under critical conditions, in terms of decomposition taking place in the condense phase but also potential toxic emissions that can be released. Toxicity, kinetics, temperature evolution do not provide a complete view of the combustion phenomenon. Beside these elements that characterise the behaviour of a material for given conditions as well as also the degree of fire hazard encountered, the energetic issue holds as an essential feature that cannot be neglected. The heat release rate (HRR) is a critical parameter that defines a fire. It does not constitute an intrinsic material property but it describes the energetic response of the couple formed by the material and its environment. Oxygen Consumption calorimetry (OC) and Carbon Dioxide Generation calorimetry (CDG) are widespread methods to calculate the HRR resulting from a combustion reaction. Apparatuses such as the FPA or the cone calorimeter have already proved their potential to qualify the burning behaviour of common fuels in addition to polymers when their data are combined with an adapted calorimetric procedure. The same approach has been applied to energetic materials. However, prior to using these techniques, it is fundamental to have identified their restrictions. These techniques provide approximate estimations of the HRR. Results are affected by the propagation of uncertainties. Several sources of uncertainties can be found. One can cite: 1. Uncertainties associated with the sample material; 2. Uncertainties associated with the test conditions; 3. Uncertainties associated with the measurements; 4. Uncertainties associated with calculation assumptions. If uncertainties cannot always be estimated, the three first sources cited have received attention in the past from the scientific community, alike the last one. The restrictions associated with the assumptions developed for using the OC and CDG principles have to be clarified. The limits of validity of the hypotheses have to be clearly defined. In particular, the present dissertation questions the relevance of the energy constants that have been specified for OC and CDG as well as their related uncertainties. One of the purposes of the research deals with the ability to estimate accurate error bars for the calculation of the HRR. Once uncertainties related to the calorimetric methods are assessed, a method adapted from the basic OC and CDG principles is introduced that allows estimating the HRR of energetic materials. The approach is based on considering the chemical decomposition of the burning compound and defining a fictitious molecule for which energy coefficients can be calculated. Nevertheless, it requires the material to be known. Finally, the question of the advantage brought by these techniques over others, in terms of accuracy, is discussed within the framework of unconventional products, such as energetic materials or compounds whose composition is ignored. The results from this work will contribute to the development of fireanalysis methodologies and validate their use with energetic materials.

The objective of this study was to synthesize and characterize new energetic polycyclic "cage" compounds. As part of a program involved in the synthesis of new polynitropolycyclic compounds, 2,6-dinitro-5-methoxy- 7-carbomethoxypentacyclo[5. 3 .0 . 0* • * . CP • i ° . 0* •8]decane has been synthesized. This is a model system which can be used to study (1) the effect of nitro substitution on the photolability of carbon-carbon double bonds and (2) to develop methods for avoiding Haller-Bauer cleavage in cage /3-keto esters when synthesizing polynitro-substituted cage compounds.

Title: The energetic cost of middle aged women during zumba lesson measured by indirect calorimetric method Objectives: The aim of this study is to assess energy cost of the middle aged women during zumba exercise. Methods: A group of 6 women (age range 27-37 years) volunteered to participate in this study. To assess the maximal oxygen consumption, we used the running test to individual maximum. Each subject took part in six lessons of zumba in commercial fitness gym. Each subject was measured during 60 min long lesson. Results: The oxygen consumption of the whole zumba exercise was 19,5±2,2 ml.kg-1 .min-1 that is 68,4 % of the maximal oxygen consumption 40,1±7,4 ml.kg-1 .min-1 measured during running test. That exactly means a caloric expenditure 404,8 kcal (or 1692,2 kJ) during one lesson of zumba. The intensity of whole class reported by HR was covered by 67,5 % from HRmax and by Borg's rates of perceived exertion (6-20) with rates 14±2 from 18±2 immediately after the maximal running test. The highest energetic cost (336, 3 kcal, resp. 1405,9 kJ) was during the main part of the lesson. Zumba can be classified as moderately challenging type of exercise, which is good for fat burning; this statement is based on values of the heart rate measured during lessons of zumba. Key words: zumba, energetic...