A safe storage of radioactive waste in repositories is an important task to protect humans and the environment from radio- and chemotoxicity. Long-term safety assessments predict the behavior of potential environmental contaminants like the actinides plutonium, uranium, or neptunium, in the near and far field of repositories. For such safety assessments, it is necessary to know the migration behavior of the contaminants in the environment, which is mainly dependent on the aquatic speciation, the solubility product of relevant solid phases, and the retardation due to sorption on surrounding minerals. Thus, an investigation of sorption processes of contaminants onto different minerals as well as the derivation of mineral specific surface complexation model (SCM) parameters is of great importance. Feldspar and mica are widely distributed in nature. They occur as components of granite, which is considered as a potential host rock for a repository in Germany, and in numerous other rocks, and thus also in the far field of nearly all repositories. However, their sorption behavior with actinides has only been scarcely investigated until now. In order to better characterize these systems and subsequently to integrate these minerals into the long-term safety assessments, this work focuses on the investigation of the sorption behavior of U(VI), Np(V), and Nd(III) as analogue for An(III) onto the minerals orthoclase and muscovite, representing feldspars and mica, respectively. All investigations were performed under conditions relevant to the far field of a repository. In addition to the extensive characterization of the minerals, batch sorption experiments, spectroscopic investigations, and surface complexation modeling were performed to elucidate the uptake and speciation of actinides on the mineral surfaces. In addition, the influence of microorganisms naturally occurring on the mineral surfaces and the effect of Ca2+ on U(VI) uptake on the minerals was studied. The obtained sorption curves exhibit a similar characteristic for orthoclase and muscovite. As expected Nd(III) shows the highest amount of sorption followed by U(VI) and finally Np(V). With spectroscopic investigations of the aquatic U(VI) solution in presence of Ca2+, the Ca2UO2(CO3)3 complex could be identified. Furthermore, with spectroscopic methods the U(VI) surface species onto orthoclase could be characterized, of which a novel uranium-carbonate surface species was observed. Based on the results of batch experiments and spectroscopic methods new SCM parameters for the sorption of U(VI), Np(V), and Nd(III) onto orthoclase and for Np(V) and Nd(III) onto muscovite could be derived. SCM parameters for U(VI) sorption onto muscovite confirmed earlier investigations. The obtained SCM parameters increase the amount of data available for sorption processes onto feldspar and mica. With this the relevance of feldspars for the sorption of actinides and lanthanides could be shown. Thus, this work contributes to a better understanding of interactions of actinides and lanthanides, in particular U(VI), Np(V), and Nd(III), with mineral phases ubiquitous in the environment. This in turn adds confidence to long-term safety assessments essential for the protection of humans and the environment from the hazards of radioactive waste.

Целью магистерской диссертации является разработка состава массы для производства глазурованного керамического гранита. В работе исследованы свойства сырьевых материалов. Определены технологические параметры производства и разработана технология производства для производства глазурованного керамического гранита. / The aim of the master's thesis is to develop the composition of the mass for the glazed ceramic granite production. The paper investigated the properties of raw materials. The technological parameters of production are determined and the production technology for the production of glazed ceramic granite is developed.

Despite extensive previous studies, the peak metamorphic conditions within the 2.0-1.8 Ga Svecokarelian orogen remain unclear, particularly regarding the deformation and migmatization events occurring between 1.87-1.80 Ga within the Ljusdal lithotectonic unit. While earlier observations indicate granulite facies metamorphism, the exact metamorphic conditions and nature of these events are still unclear. This thesis aims to determine the pressure-temperature range associated with the peak metamorphic conditions by analyzing mineral assemblages in the leucogranite of Sörfjärden, located east of Gnarp, Sweden. Through optical microscopy and electron microprobe analysis, a complex mineral assemblage was identified, including alkali feldspar, plagioclase, garnet, quartz, biotite, sillimanite, and Fe-Zn-rich spinel, with accessory minerals such as monazite, zircon, and rutile. Secondary chlorite and kaolinite were also observed. Ternary-feldspar thermometry revealed crystallization temperatures of 750 ˚C. Thermobarometric modeling of the bulk rock chemical composition, using the software GeoPS, indicated peak pressure-temperature conditions of 2.0–2.4 kbar and 740–770 ˚C, defined by the peak mineral assemblage garnet, plagioclase, quartz, sillimanite, and spinel. Melt structures on biotite and alkali feldspar were inferred to have formed during the second migmatization event, suggesting that granulite facies conditions were reached during the first migmatization event. While these findings provide insights into the metamorphic history of the Svecokarelian orogen, further investigations into the influence of Zn on the produced models are warranted. Addressing the limitations of current thermodynamic models would improve our understanding of this complex geological system. / Trots omfattande tidigare studier är de metamorfa förhållandena i den Svekokarelska orogenesen (2.0–1.8 Ga) fortfarande oklara, särskilt gällande de deformations- och migmatiseringsprocesser som inträffade mellan 1.87–1.80 Ga. Även om tidigare observationer tyder på metamorfos med granulitfacies är de exakta metamorfa förhållandena hos och karaktären av dessa processer fortfarande osäkra. Denna studie syftar till att fastställa det tryck-temperaturintervall som är förknippat med de högsta graderna av metamorfos genom att analysera mineralsammansättningar i leukograniten i Sörfjärden, beläget öster om Gnarp, Sverige. Genom optisk mikroskopi och elektronmikrosonderingsanalys identifierades en komplex mineralsammansättning: alkalifältspat, plagioklas, granat, kvarts, biotit, sillimanit och Fe-Zn-rik spinell, där monazit, zirkon och rutil är accessoriska mineral. Klorit och kaolinit är sekundära. Ternär fältspatstermometri påvisade en kristalliseringstemperatur vid 750 ˚C. Termobarometrisk modellering av bergartens kemiska sammansättning med programmet GeoPS indikerade maximala tryck-temperaturförhållanden på 2.0–2.4 kbar och 740–770 ˚C; mineralsammansättningen under dessa förhållanden var granat, plagioklas, kvarts, sillimanit och spinell. Smältstrukturer på biotit och kalifältspat tolkades ha bildats under den andra migmatiseringen, vilket medför att granulitfacies uppnåddes under den första migmatiseringen. Fastän dessa resultat ger insikter i den Svekokarelska orogenesens metamorfa historia är det motiverat att vidare undersöka inverkan av Zn på de framställda modellerna. Att hantera begränsningarna i nuvarande termodynamiska modeller skulle förbättra vår förståelse av detta komplexa geologiska system.

Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-09-20T16:23:02Z No. of bitstreams: 1 Dissertacao_AmandaCristineSantosdaCosta (1).pdf: 3976192 bytes, checksum: 2af7ce18076b8c783880d3ac0c5acba5 (MD5) / Made available in DSpace on 2017-09-20T16:23:02Z (GMT). No. of bitstreams: 1 Dissertacao_AmandaCristineSantosdaCosta (1).pdf: 3976192 bytes, checksum: 2af7ce18076b8c783880d3ac0c5acba5 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / importante sistema de drenagem da Região Serrana do estado do Rio de Janeiro. É caracterizada por clima tropical de altitude úmido com pluviosidade média anual de 2300 mm e temperatura média anual de 19ºC. A geologia local é definida por granitos e gnaisses representativos da região sudeste brasileiro com domínio de quatro principais unidades litoestratigráficas: suíte Serra dos Órgãos (53%), complexo Rio Negro (14%), suíte Cordeiro (13%) e suíte Nova Friburgo (7%). A área é predominantemente florestada, porém há interferência antropogênica como atividades de agricultura, pastagem e ocupação urbana. Amostras de água foram coletadas em Fevereiro e Agosto de 2013 em 21 pontos selecionados de forma a contemplar as variações litológicas e de formas de uso do solo. Uma alíquota foi filtrada e acidificada para posterior análise de cátions e para a análise de ânions as amostras foram filtradas e congeladas. Os elementos Na+, Mg2+, Ca2+, K+, SiO2 foram analisados por ICP-OES, o elemento Al3+ por ICP-MS e PO4 3-, Cl- e SO4 2- por cromatografia iônica. Dados secundários foram levantados complementando as análises realizadas (litogeoquímica, concentração de compostos fosfatados e nitrogenados, parâmetros físico-químicos e composição da chuva). Uma análise estatística de agrupamentos separou as sub-bacias de acordo com as formas de uso do solo, mostrando forte influência sobre a qualidade das águas. Para a análise dos processos intempéricos foi selecionada uma sub-bacia de cabeceira situada em uma unidade de conservação cuja floresta encontra-se em seu clímax de maturidade, livre de influência antrópica direta. Foram reunidas informações de mineralogia essencial da subbacia, índices de saturação (PHREEQC), composição química da chuva e fluxo de elementos maiores para definir as principais reações de intemperismo atuantes e quantificar o processo de intemperismo. O plagioclásio foi identificado como principal mineral intemperizado, sendo consumido em uma taxa de 649 mol ha-1 ano-1 formando os minerais caulinita e gibbsita, e contribuindo com a liberação de no mínimo 818 e no máximo 1491 mol ha-1 ano-1 de silício no rio (valor medido). Para explicar todo este fluxo de silício medido, o solo deveria ser composto por 14% de caulinita e 86% de gibbsita em percentual relativo às duas fases minerais. Com relação à qualidade das águas superficiais foi proposta a razão Na:Si como uma alternativa simples e eficiente de avaliação da influência antrópica sob as condições de toda a bacia. Razões acima de 0,6 indicariam um ambiente afetado por atividade antrópica. Verificou-se uma boa correlação do proxy sugerido com outros compostos indicadores de poluição, com razão Na:Si mínima de 0,4 e máxima de 0,6 para pontos de cabeceira. Baixas razões de Na:Si, porém com concentrações mais elevadas de compostos nitrogenados e fosfatados foram associadas a áreas agrícolas. Para áreas onde é observada a influência de atividade antrópica urbana (esgotos domésticos), a razão apresentou valores elevados com máximo de 5,1. / The Piabanha basin is part of the Paraíba do Sul River system. It is an important drainage in the Rio de Janeiro mountainous region. It is characterized by humid altitude tropical climate with 2300mm of annual rainfall and 19ºC of average annual temperature. The local geology is defined by granites and gneisses representative of the Brazilian southeast region with the dominance of four main lithostratigraphic units: Serra dos Órgão suite (53%), Rio Negro complex (14%), Cordeiro suite (13%) and Nova Friburgo suite (7%). The area is mainly forested, however there are anthropogenic interference such as agricultural activities, pasture and urban area. Water samples were collected in February and August 2013 at 21 selected points. They were chosen to cover lithological variations and land use patterns. One aliquot was filtered and acidified for further cation analysis. Another sample aliquot was filtered and frozen to anion analysis. The elements Na+, Mg2+, Ca2+, K+, SiO2 . were analyzed by ICPOES the element Al3+ by ICP-MS and PO4 3-, Cl- and SO4 2- by ionic chromatography. Data from literature were collected (litogeochemistry, phosphate and nitrogen compounds concentration, physico-chemical parameters and rain composition). The statistical cluster analysis classified the sub-basins according to land use patterns, due to the strong influence on water quality. To the weathering processes analysis, a headwater sub-basin was selected. It is located in a conservation unit with a climax forest, free of direct anthropogenic influence. Information on this sub-basin’s essential mineralogy, saturation indexes, rain chemical composing and major elements flow were gathered so the main weathering reactions were defined in order to quantify the weathering process. The plagioclase was identified as the main weathered mineral, being consumed at a rate of 649 mol ha-1 year-1 forming the minerals kaolinite and gibbsite and contributing to the liberation of 818 at least and 1491 mols maximum ha-1 year-1 of silicon on the river (measured value). In order to explain all this measured silicon flow, the soil should be composed by 14% of kaolinite and 86% of gibbsite in percentage relative of the two mineral phases. Regarding the water quality, the Na:Si ratio was proposed as a simple and efficient way to evaluate the anthropogenic influence. Ratios above 0,6 would indicate an environment affected by anthropogenic influence. There was a good correlation of the suggested proxy with other pollutants indicator compounds, with a ratio of Na: Si minimum of 0,4 and maximum of 0,6 for headwater points. Low ratio values of Na:Si related with high concentration of N and P compounds are associated with agricultural areas because of the use of fertilizers. Areas with high urban anthropic activity showed the highest ratio values with a maximum value of 5,1.

We have entered the age of big data. Massive datasets are now common in science, government and enterprises. Yet, making sense of these data remains a fundamental challenge. Where do we start our analysis? Where to go next? How to visualize our findings? We answers these questions by bridging Data Mining and Human- Computer Interaction (HCI) to create tools for making sense of graphs with billions of nodes and edges, focusing on: (1) Attention Routing: we introduce this idea, based on anomaly detection, that automatically draws people’s attention to interesting areas of the graph to start their analyses. We present three examples: Polonium unearths malware from 37 billion machine-file relationships; NetProbe fingers bad guys who commit auction fraud. (2) Mixed-Initiative Sensemaking: we present two examples that combine machine inference and visualization to help users locate next areas of interest: Apolo guides users to explore large graphs by learning from few examples of user interest; Graphite finds interesting subgraphs, based on only fuzzy descriptions drawn graphically. (3) Scaling Up: we show how to enable interactive analytics of large graphs by leveraging Hadoop, staging of operations, and approximate computation. This thesis contributes to data mining, HCI, and importantly their intersection, including: interactive systems and algorithms that scale; theories that unify graph mining approaches; and paradigms that overcome fundamental challenges in visual analytics. Our work is making impact to academia and society: Polonium protects 120 million people worldwide from malware; NetProbe made headlines on CNN, WSJ and USA Today; Pegasus won an opensource software award; Apolo helps DARPA detect insider threats and prevent exfiltration. We hope our Big Data Mantra “Machine for Attention Routing, Human for Interaction” will inspire more innovations at the crossroad of data mining and HCI.

One of the most sustainable pathways of sewage sludge treatment in recent years has been thermal conversion. The benefits of thermal treatment of sewage sludge are the recovery of energy or valuable chemical products, the destruction of harmful organic compounds, the separation of heavy metals from the P-rich coarse ash fraction, and the decreased and sanitized ash volume. The ashes created by these thermal conversion processes of sewage sludge are often rich in P that is mostly present in minerals with low plant-availability such as apatite. Due to the enrichment of P in the created ashes, a variety of post-processing steps have been developed to recover P from sewage sludge ashes. One proven way for the sus-tainable recovery of P from such ashes is thermal post-processing with alkaline salts, e.g., Na2SO4 or K2CO3, which was able to transform less plant-available phosphates in the sewage sludge into more plant-available alkali-bearing phos-phates. Based on these results, one could facilitate creating these phosphates with enhanced plant-availability by providing the chemical potential to form them already during the thermal conversion process of sewage sludge.   This thesis aims to increase the current knowledge about the ash transformation processes of P and to suggest suitable process parameters for the alteration of the phosphate speciation in sewage sludge ashes by co-conversion with alkaline-rich agricultural residues. More specifically, the possibility of incorporating K derived from agricultural residues in phosphate structures derived from sewage sludge was evaluated with respect to the influence of the process temperature, the conver-sion atmosphere, and the fuel mixture. The studied parameters were chosen to generate knowledge relevant for fluidized bed gasification processes, with a spe-cial focus on dual fluidized bed (DFB) gasification systems. The applicability of feldspar bed materials in fluidized bed gasification systems was investigated to enable the substitution of the commonly used olivine, which often contains heavy metals (potentially contaminating recovered ashes), and quartz, which is very reactive towards fuel-derived K and potentially leads to bed material fragmentation and bed agglomeration (Paper I & II). Subsequently, the thermodynamic potential for the alteration of the P-species in sewage sludge ash during co-combustion and co-gasification processes with agricultural residues was investigated (Paper III). Thereafter, an experimental evaluation of the ash transformation chemistry in thermal conversion processes of sewage sludge with different types of alkali-rich agricultural residues in temperatures relevant for flu-idized bed technology was conducted (Paper IV & V). The methodology employed was chosen with respect to the state of technology of the specific investigated process. Paper I & II applied SEM, EDS, XRD, and thermodynamic equilibrium modeling for bed material samples derived from an industrial indirect gasifier. Paper III applied thermodynamic equilibrium calcula-tions to theoretically evaluate ash compositions resulting from co-conversion of sewage sludge and agricultural residues. Paper IV & V employed SEM, EDS, ICP-AES/MS, XRD, and thermochemical modeling on ash samples derived from single pellet lab-scale experiments. The results obtained by analysis of bed material from indirect wood gasification showed the difference in interaction mechanism for K-feldspar and Na-feldspar, most notably the enhanced disintegration of Na-feldspar by K originating from the fuel (Paper I & II). Thermodynamic models employed for fuel mixtures of sewage sludge and agricultural residues showed the thermodynamic preference for the formation of the desired alkali-bearing phosphates (Paper III). Experi-ments conducted with these fuel mixtures (Paper IV & V) supported the theo-retical findings, and the influence of temperature and process conditions could be obtained. However, practical investigations also showed that attainment of the desired ash composition is subject to significant restrictions. Derived from the elaborated results and discussions, it was possible to assess the critical process and fuel parameters for the development of up-scaled gasification processes focusing on the conversion of sewage sludge with the aim of creating improved phosphate formation in the ash. The selection of a suitable bed material in fluidized bed conversion and the transformation mechanisms defining the ash chemistry were found to be of vital importance for future applications. The pur-suit of the predefined aims in reference to P-recovery from sewage sludge has led to a multitude of suggestions for suitable process parameters that must be ad-dressed in future bench- and pilot-scale experimental runs.

Isolated granitic rock bodies (granites, granodiorites, quartz monzonites) in the vicinity of Benson in southeastern Arizona were studied to trace the behavior of rock weathering. Thin sections of fresh granites were examined to characterize the original mineralogy which consisted mainly of quartz, feldspars, and micas. The weathering products show up on the granites as grus and soil profiles as well as down slope in the basin deposits. X -ray diffraction studies of the < 2 micrometers fraction of the weathering products proved illite, smectite, illite-smectite mixed layer, and kaolinite to be the dominant clays; quartz and feldspar also persisted into this size fraction. Silt sized material produced similar results. The quartz monzonite of Texas Canyon afforded a special study of the initial weathering stages of feldspars and micas. In the < 2 micrometers fraction obtained from granitic material placed in an ultra sonic bath, the feldspars weathered to a Na-montmorillinite while biotite weathered to vermiculite.

The aim of the project was to study the mineral, chemical and morphological characteristics of the fallout dust samples. The dust fallout samples were collected at five different sites following the internationally accepted standard procedure for collection and analysis, South African National Standard and American Standard for Testing Methods (ASTM) D1739-98 (2010). Passive single buckets containing ¾ of distilled water and 10.0 ml of sodium hypochlorite (NaOCl) solution, hoisted at a height of about 2.5 m were exposed from March – June 2013 and were collected every month, taken to the laboratory for characterization. First, the samples were filtered and mass concentrations per month were gravimetrically measured. The samples were then prepared for further characterization by the MicroScan Particle Analyser (MSPA)(Microscope UOP UB 100j) which measured the mineral content and the Scanning Electron Microscope - Energy Dispersive X- ray (SEM - EDX) measured the images of different particles (size, shape) and their elemental content. The results from the MicroScan analysis showed the prevalence of sandy rounded-shaped quartz (SiO2) particles across all sites. Minerals detected within the crustal material at all sites were quartz (SiO2), haematite (Fe; Fe2O3; Al2O3), feldspar (Na, K, Mg, Ca: AI2Si2O8), garnet (SiO4), aluminium silicates (AI2Si2O8) and calcium hydroxide [Ca (OH)2]. Evidently, sites A, B and C dominated the abundance of these minerals. On the other hand, sites D and E showed fine and rounded quartz and quartzite with various trace metal oxides. Measured elements in decreasing concentrations were Si, Ca, P, Al, K, S, Fe, Cu, Ti and Mg. Both coarse particle (2.5 - 10.0 μm) and fine particle sizes ranges (< 1.0 to 2.5 μm) were detected. Large irregular shaped particles sizes were common and were linked to crustal material. The results provide good baseline information which requires further characterization of samples by different analytical techniques and validation of possible sources. The ICP-MS was used to determine the elemental composition of dust fallout and the mean concentration of the elements of concern ranged from 1.1 - 2.6 for As, 0.2 - 0.6 for Cd, 17.0 - 21.9 for Ni, 449.8 - 751.1 for Pb, 9.9 - 22.3 for V and 101.7 - 293.0 μg/m3 for Zn. The elements such as Cd exceeded the set limit 0.005 μg/m3 by OSHA (2015) and NIOSH (2007); Pb exceeded the set standard of 0.5 μg/m3 set by OSHA (2015), NIOSH (2007), WHO (2000), USEPA (2012) and DEA (2013). The rest of the elements fell within the set guidelines by various regulatory national and international bodies. The study concludes that, although, all the sampling sites recorded the dust fallout rates within the SANS 1929 (2011) and DEA (2013) average RESIDENTIAL limit of 600 mg/m2/day, the future accumulation and exceedances cannot be ruled out owing to the increasing developments in urban areas / Environmental Sciences / M. Sc. (Environmental Science)

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