Nuclear energy presents environmental benefits, yet the challenge of radioactive waste management persists. Advanced solutions, such as Molten Salt Reactors (MSRs), require a more profound understanding of molten salt chemistry. This research aims to develop tools, including a depletion simulator, molten salt electrochemical simulator, and a fluoride-based thermodynamic reference electrode for electrochemical purification. The computationally inexpensive depletion simulator allows for exploration into extraction and processing strategies for molten salt reactors. An illustrative case study on Mo-99 production from MSRs demonstrates the practical application of the theoretical framework, emphasizing the need for optimization in extraction effectiveness and separation difficulty. The electrochemical simulator, employing first-principles models, contributes to both nuclear technology and the broader field of electrochemistry. Detailed analyses of linear sweep voltammetry (LSV) for uranium deposition, coupled with numerical simulations for diffusion coefficient measurements, enhance precision in experimental methodologies. The study into fluoride-based thermodynamic reference electrodes provides validation of boron nitride as a viable ion-exchange membrane permeation of oxide impurities as a contributing factor to reference electrode failure, and an investigation of an alternative reference electrode chemistry based on the equilibrium between U3+ and U4+. This novel reference electrode chemistry enabled electrochemical purification of fluoride-based salts which were characterized with square wave voltammetry and have less than 30 ppm O2-. In summary, this work not only advances theoretical understanding but also provides practical tools for nuclear energy and electrochemical processes. Its interdisciplinary approach of integrating theory, computation, and experimentation represents a significant stride toward the responsible and balanced utilization of nuclear power to address global energy needs and challenges.

Mule deer (Odocoileus hemionus) from the US Air Force Academy (USAF A) at Colorado Springs, Colorado have shown antler fractures and tooth lesions. Brittle bones and tooth lesions have been associated with high ingestion of fluorides. The present study compared prevalence and severity of tooth lesions with fluoride content in teeth, bones and antlers of mule deer from USAF A with deer from other two areas in Colorado. Mule deer tissues were collected during 1993-1995 from: USAF A (N=262), Pinon Canyon Maneuver Site (pCMS, N=24), and game management units (GMU's) in northwestern Colorado (N=16). The severity of tooth lesions was rated using a 0 (normal) to 5 (severe hypoplasia) scale. In all areas the median lesion score was 1; the highest score in USAFA was 5 vs. 3 in the other areas. Median fluodide concentrations (Jlg/g d.w.) were higher (p<0.002) in second incisors and bones of mule deer collected at the USAFA (669.9, N=246 incisors, 744.5, N=247 bones) than in deer from PCMS (507.3; 494.7, N=24) and GMU's (426.2,466.2, N=16), respectively. Within the USAF A, median fluoride concentrations in teeth and bones were lower (P<O. 001) in fawns and yearlings than in older animals and in males (> I. 5 years) than in females. Median fluoride concentrations were lower (P<O. 001) in deciduous than in permanent teeth. Median concentrations of fluoride were higher (P<O.OO1) in non-erupted teeth than in deciduous teeth and bone indicating a high rate of accumulating fluoride in growing hard tissue. Fluoride concentration was higher (P<O. 00 1) in teeth with lesions than without lesions. / Master of Science

Thesis advisor: Amir Hoveyda / Chapter 1: E- and Z-, Di- and Trisubstituted Alkenyl Nitriles through Catalytic Cross MetathesisWe have described the development of several catalytic cross-metathesis strategies, which can deliver a considerable range of Z- or E-disubstituted alkenyl nitriles and their corresponding trisubstituted variants. Through careful examination of the steric and electronic attributes of the starting materials, a Mo-based monoaryloxide pyrrolide or chloride complex may be the optimal choice depending on the reaction type. In the event, equimolar amounts of the two substrates are necessary to maximize reaction efficiency; a pyridine ligand is more desirable than a phosphine ligand, as a stabilizing ligand for a Mo-based complex, for improving reaction stereoselectivity. We also highlighted the utility of this approach with the synthesis of several biologically active compounds, such as LR5182 (Cocaine abuse treatment), alliarinoside (anti-feedant), perhydrohistrionicotoxin (natural product), CC-5079 (anti-cancer) and indatraline (anti-depressant). Chapter 2: Traceless Protection for More Broadly Applicable Olefin Metathesis We have devised an operationally simple in-situ protection/deprotection strategy that significantly expands the scope of kinetically controlled catalytic olefin metathesis. Pretreatment of an olefin containing a protic group with commercially available HB(pin) or HB(trip)2 is sufficient for generating the desired product efficiently through the catalytic cross-metathesis reaction. A wide range of stereochemically defined Z- and E-alkenyl halides and boronates as well as Z-trifluoromethyl-substituted alkenes with a hydroxy or carboxylic acid group were prepared. We also discovered that a small amount of HB(pin) may be used for the removal of residual water and impurities, significantly enhancing the efficiency of a multigram-scale olefin metathesis transformation. Chapter 3: E- and Z-Macrocyclic Trisubstituted Alkenes for Natural Product Synthesis and Skeletal Editing We have introduced a reliable catalytic strategy for the synthesis of a variety of macrocyclic trisubstituted olefins in either stereoisomeric form. This was achieved by overcoming the unexpected difficulties through careful mechanistic studies, including addressing complications arising from pre-metathesis alkene isomerization. Macrocyclic ring-closing metathesis can be performed with a commercially available Mo-based complex and an easily accessible linear diene precursor. Accordingly, we can synthesize a skeletally diverse array of otherwise difficult-to-access macrocyclic alkenes, a critical set of compounds in drug discovery, in either isomeric form. The utility of the method is highlighted in two instances. The first is the near complete reversal of substrate-controlled selectivity in the generation of the macrolactam intermediate, in the total synthesis of the anti-fungal agent Fluvirucin B1. The second is an exceptionally stereoselective late-stage formation of a 24-membered macrocyclic E-trisubstituted alkene, enabling the completion of the total synthesis of a cytotoxic natural product dolabelide C, which is seven times more efficient than that reported previously. Chapter 4: Stereodefined Alkenes with a Fluoro-Chloro Terminus as a Uniquely Enabling Compound Class We have offered a practical solution for the synthesis of trisubstituted alkenyl fluorides by unveiling a widely applicable strategy for stereodivergent synthesis of olefins bearing a fluoro and chloro terminus. The core transformation is unprecedented: cross-metathesis between two trisubstituted olefins, one of which is a commercially available but scarcely utilized trihalo alkene. Alkenes bearing a fluoro,chloro-terminus are versatile substrates for the generation of otherwise difficult-to-access trisubstituted alkenyl fluorides, through stereospecific catalytic cross-coupling reactions. We also highlighted the utility of the method throguh synthesis of, among others, a fluoro-nematic liquid crystal component, peptide analogs bearing an E- or a Z-amide bond mimic, and all four stereoisomers of difluoro-rumenic ester (anti-cancer). / Thesis (PhD) — Boston College, 2021. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Syfte: För att främja munhälsan hos barn var syftet med studien att undersöka vårdnadshavares erfarenheter av den hälsofrämjande undervisningen i munhälsa som utförts av tandhygieniststudenter bland skolbarn i årskurs 1 och 2. Metod: Studiedesignen var en tvärsnittsstudie som genomfördes via en digital enkät. Urval var vårdnadshavare till skolbarn i årskurs 1 och 2 som deltagit i den hälsofrämjande undervisningen. Totalt deltog fyrtiofem skolbarn i undervisningen och sexton vårdnadshavare besvarade enkäten.Statistisk analys utfördes genom Spermans rangkorrelationkoefficient (rho). Resultat: Vårdnadshavarnas erfarenheter efter den hälsofrämjande undervisningen i skolan påvisade att majoriteten av barnen visat intresse för tandborstning. Vårdnadshavarna nämnde att undervisningen gav ökad motivation, kunskap och medvetenhet. Ett icke signifikant medel-starkt positivt samband visades mellan intresse för att borsta tänderna och om barnet hade pratat om tandborstteknik hemma efter undervisningen (r=0,306, N=16, p=0,249). Slutsats: Vårdnadshavarna uppgav att barnen visat intresse till tandborstning efter undervisningen och att de pratat om tandborstteknik i sin hemmiljö. Det belyser att den hälsofrämjande undervisning kan bidra till medvetenhet kring munhälsa och goda vanor. Vidare forskning behövs för att undersöka effektiviteten av hälsofrämjande undervisning i munhälsa. / Aim: In order to promote the oral health of children, the aim of the study was to investigate guardians' experiences of oral health promotion education carried out by dental hygiene students among school children in grades 1 and 2. Method: The study design was a cross-sectional study conducted via a digital questionnaire.The sample was guardians of children in grades 1 and 2 who participated in the health promotion education. A total of forty-five school children participated in the education and sixteen guardians answered the questionnaire. Statistical analysis was performed using Spearman's rank correlation coefficient (rho). Results: After the education, most children displayed an interest in brushing their teeth, and the guardians mentioned increased motivation, knowledge and awareness. A non-significant medium-strong positive correlation was shown between interest in brushing teeth and discussing toothbrushing techniques at home after the education (r=0.306, N=16, p=0.249). Conclusion: The guardians stated that the children showed interest in toothbrushing after the education and that they talked about toothbrushing techniques in their home environment. This highlights that health promotion education can contribute to oral health awareness and good habits. Further research is needed to investigate the effectiveness of health promotion education in oral health.

This work demonstrates how ICP-MS can be employed to evaluate cesium volatilization from LiF-BeF2 (Flibe) salt with ab initio molecular dynamics studies used as corroborating data to better understand cesium behavior. Using mixtures of Flibe with 2 mol% CsF, it was found that cesium was stable within the salt melt at temperatures between 500-650°C over a time span of 8 hours. At 800°C, cesium vaporized from the salt at a rate of 0.83% / hr with a mass flux of 0.0023 g Cs / cm2hr. The atomistic modeling results show poor solvation of Cs at 500°C and 800°C, with stability preferred at 650°C. Specialized equipment and procedures were needed to enable this work, especially those required for safe handling of beryllium containing salts. The methods, custom equipment, and important considerations for working with high-temperature fluoride salts are detailed in this thesis.

京都大学 / 新制・課程博士 / 博士(人間・環境学) / 甲第25387号 / 人博第1129号 / 京都大学大学院人間・環境学研究科相関環境学専攻 / (主査)教授 内本 喜晴, 教授 田部 勢津久, 教授 吉田 鉄平, 教授 雨澤 浩史 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DFAM

L’objectif de ce travail est d'envisager les modifications de formulation ou de procédé dans la technologie de geltrusion développée par Batscap pour augmenter la fiabilité des supercondensateurs en limitant l'autodécharge. La technologie repose sur l’extrusion simultanée de polymères (PVDF, PVDF-HFP), d’un solvant (PC) et de charges (CA, NC). Le mélange réalisé en extrusion bivis est ensuite filmé et laminé sur le collecteur en aluminium. Dès lors, il a été fondamental de chercher à comprendre les interactions entre les différents composants de l’électrode, avec l’étude de la miscibilité du système ternaire polymère/polymère/solvant puis l’étude de l’adsorption du solvant sur les charges. Cette démarche a permis une meilleure compréhension des phénomènes impliqués en passant par une caractérisation approfondie du complexe, dans sa formulation actuelle aux différentes étapes du procédé. Ensuite, des modifications de formulations ont été envisagées. En particulier, l'effet de la structure et de la masse molaire des polymères sur l’adhésion a été étudié. Dans tous les cas, il a été envisagé de tester les possibilités offertes par l'utilisation d'un solvant différent (DMSO). Ce dernier étant un meilleur solvant du PVDF est plus facile à éliminer que le PC. Enfin, à partir des données rhéologiques du mélange, une modélisation mécanique, en utilisant le modèle de Maxwell à plusieurs temps de relaxation, a été menée dans l'opération de laminage du mélange en prenant en compte un comportement viscoélastique du gel. Toutes ces études ont permis de conclure sur les modifications pertinentes de la formulation ainsi que des conditions du procédé / The objective of this work is to consider changes in formulation or process of the geltrusion technology developed by Batscap to increase the reliability of supercapacitors by limiting self-discharge. The technology is based on the simultaneous extrusion of polymers (PVDF, PVDF-HFP), solvent (propylene carbonate) and fillers (activated carbon, carbon black). The mixture carried out in a twin-screw extrusion is then filmed and laminated on the aluminium collector. Therefore, it was important to understand the interactions between the different components of the electrode, and especially to study the miscibility of the ternary system polymer/polymer/solvent and also the adsorption of solvent on fillers. This approach has allowed a better understanding of the phenomena involved through a characterization of the complex, in its current form at different stages of the process. Then, changes in formulations were considered. In particular, the effect of the structure and molecular weight of the polymers on adhesion was studied. In all cases, it was envisaged to test the possibilities offered by the use of a different solvent (dimethyl sulfoxide). The latter being a better solvent for the PVDF, is also easier to remove than propylene carbonate. Finally, from the rheological data of the mixture, a mechanical modeling, using the multimodal Maxwell model, was conducted in the lamination step taking into account of the viscoelastic behavior of the gel. All these studies allow us to conclude on the relevant changes in the formulation and process conditions

A exposição a baixos níveis de chumbo é associada a desordens cognitivas e neurológicas em crianças. Foi descrito um aumento dos níveis de chumbo no sangue de crianças que vivem em comunidades que recebem água fluoretada. Este estudo testou se flúor a 100 ppm na forma de ácido fluorsilícico na água induziria aumento na concentração de chumbo no sangue e tecidos calcificados de ratos Wistar expostos a baixos níveis de chumbo desde a idade gestacional. Ratas foram separadas em quatro grupos: controle e grupos que receberam água que continham 100 mg/L de fluoreto (F), 30 mg/L de chumbo (Pb), ou 100 mg/L de F e 30 mg/L de Pb (F+Pb), desde uma semana antes do acasalamento até que os filhotes completassem 81 dias. Todos os animais foram pesados ao longo do experimento. Sangue e tecidos calcificados foram coletados com 81 dias para análise de chumbo, flúor e fósforo em esmalte, dentina, osso total, osso superficial e sangue. Chumbo foi determinado por ICP-MS (Inductively Coupled Plasma Mass Spectrometry). Flúor foi medido através de elétrodo íon-específico e fósforo foi determinado por reação colorimétrica. As concentrações de chumbo triplicaram no grupo F+Pb (76.7±11.0 µg/dL) em comparação ao grupo Pb (22.6±8.5 µg/dL)(p <0.001), com a mesma tendência observada em todos os tecidos calcificados analisados (p <0.001 para todas as comparações). No esmalte, as concentrações de chumbo analisadas foram 2.5 vezes mais altas no grupo F+Pb em comparação ao grupo Pb (4,369±1,353 µg/g versus 1,768±1,892 µg/g). Na dentina, a concentração de chumbo encontrada no grupo F+Pb era 8.5±2.0 µg/g versus 4.9±1.7 µg/g no grupo Pb. Na superfície óssea, a concentração de chumbo encontrada no grupo F+Pb era 3.1 vezes maior do que as determinadas no grupo Pb, com 28.0±10.6 e 9.0±3.7 µg/g nos grupos F+Pb e Pb, respectivamente. No osso total, os valores de chumbo dobraram no grupo F+Pb (14.2±2.6 µg/g) em comparação com o grupo Pb (6.8±1.7 µg/g). Os valores de chumbo estavam abaixo do limite de detecção na maioria das amostras dos grupos Controle e F. As concentrações de flúor aumentaram em ambos os grupos expostos a flúor (F e F+Pb), com diferenças estatisticamente significantes dos grupos controle e Pb, mas nenhuma diferença foi encontrada nas concentrações de F entre os grupos F e F+Pb em quaisquer dos tecidos calcificados testados. Em conclusão, este estudo mostra um aumento nas concentrações de chumbo no sangue total, esmalte, dentina, superfície óssea e osso total em ratas com 81 dias expostas ao flúor e chumbo desde o período pré-natal. / Low-level lead exposure is linked to cognitive and neurological disorders in children. An increased risk for higher blood lead levels was described for children living in communities that receive fluoridated-water. This study tested whether water fluoride would induce increases in the blood and calcified tissue lead concentrations in Wistar rats exposed to low lead levels since gestational age. Female rats were allocated in four groups: control, and 3 groups that received water containing 100 mg/L of fluoride (F), 30 mg/L of lead (Pb), or 100 mg/L of F and 30 mg/L of Pb (F+Pb). Females mated and delivered their pups receiving the same water treatment. Female pups were maintained on the same water regimen until day 81. Lead was determined by ICP-MS (Inductively Coupled Plasma Mass Spectrometry), and fluoride was measured by ion-specific electrode in the whole blood, superficial enamel, dentine, surface bane, and whole bane. Mean whole blood lead concentrations triplicated in the F+Pb group (76.7±11.0 µg/dL) in comparison to the Pb group (22.6±8.5 µg/dL)(p < 0.001), with the same trend observed in all calcified tissues analyzed (p < 0.001 for all comparisons). In the enamel, mean lead concentrations were 2.5 times higher in the F+Pb group compared with the Pb group (4,369±1,353 µg/g versus 1,768±892 µg/g). In dentine, mean lead concentration found in F+Pb group was 8.5 ±2.0 µg/g versus 4.9±1.7 µg/g in the Pb group. In the bane surface, the mean lead concentration found in the F+Pb group was 3.1 times that determined in the Pb animals, with 28.0±10.6 and 9.0±3.7 µg/g in the F+Pb and Pb groups, respectively. In whole bane, mean lead values doubled in the F+Pb group (14.2±2.6 µg/g) in comparison with the Pb group (6.8±1.7 µg/g). Lead values were below detection limit in most Control and F group samples. Fluoride concentrations were increased in both groups exposed to fluoride (F and F+Pb), with statistically significant differences from the control and Pb groups, but no differences in the F concentrations were found between the F and F+Pb group in any of the calcified tissues tested. In conclusion, this study shows a fluoride-induced increase in the concentrations of lead of whole blood, enamel, dentine, surface bane and whole bane of 81-day female rats exposed to lead since gestational age, suggesting that a biological effect not recognized so far may underlie the epidemiological association between increased blood lead levels in children living in water-fluoridated communities.

Hauptaufgabe dieser Promotionsarbeit war es, eine neue Sol-Gel basierte Syntheseroute zur Darstellung edelmetallbeladener (Pd, Pt, Ag und Au) Aluminiumhydroxidfluoride zu entwickeln. Derartige Katalysatoren besitzen sowohl Lewis- als auch Brønsted-saure, sowie hydrogenierungsaktive Zentren. Solche multifunktionellen Katalysatoren können für mehrstufige Umsetzungen von Substraten in Eintopfverfahren eingesetzt werden. Das Potential der dargestellten Katalysatoren wurde in der zweistufigen Umsetzung von Citronellal zu Mentholen und der dreistufigen Reaktion von Citral zu Mentholen gezeigt. / The main aim of this thesis was to develop a new sol gel based synthesis route to noble metal loaded (Pd, Pt, Ag and Au) aluminium hydroxide fluorides. These catalysts provide Lewis as well as Brønsted acidity and hydrogenation ability. Those multifunctional catalysts can be used for multi step conversions of substrates performed in a one pot process. The potential of the synthesized catalysts was shown in the two step conversion of citronellal to menthols and in the three step conversion of citral to menthols.

Aluminiumfluorid (HS-AlF3), das mit Hilfe des Sol-Gel-Verfahrens unter nicht-wässrigen Bedingungen hergestellt wird, weist eine extrem große Oberfläche und eine hohe Lewis-Acidität auf, die mit den stärksten bekannten Lewis-Säuren wie SbF5 und ACF vergleichbar ist. Diese ungewöhnlichen Eigenschaften werden im Ergebnis einer neuen Sol-Gel-Synthese erhalten, die die Fluorolyse eines Aluminium-Alkoxids durch wasserfreien Fluorwasserstoff in organischen Lösungsmitteln zur Grundlage hat. Das zunächst in einer amorphen, katalytisch inaktiven Vorstufe mit großer Oberfläche gebildete Gel wird nach anschließender Trocknung mit gasförmigen Fluorierungsmitteln nachfluoriert, wobei die aktive Form des HS-AlF3 erhalten wird. Im Rahmen der vorliegenden Arbeit wurden alle Schritte dieses Syntheseweges untersucht und die Ergebnisse einschließlich einer detaillierten Analyse der erhaltenen Materialien diskutiert. Des Weiteren wurde HS-AlF3 durch eine Imprägnierungs-Methode auf das Trägermaterial Al2O3 aufgetragen, wobei verschiedene Beladungen mit HS-AlF3 getestet wurden. Die Eigenschaften des HS-AlF3/Al2O3 als Lewis-Säure-Katalysator wurden mittels der Dismutierung von CHClF2 und der Isomerisierung von CBrF2CBrFCF3 bestimmt. Die Herstellung von AlFyOx mit Hilfe des Sol-Gel-Verfahrens ist ebenfalls beschrieben, wobei das Produkt amorph ist und eine große Oberfläche von bis zu 240 m2/g aufweist. / Aluminum fluoride (HS-AlF3) prepared via sol-gel synthesis route under non-aqueous conditions exhibits high surface area and an extremely strong Lewis acidity, comparable with some of the strongest known Lewis acids such as SbF5 and ACF. The basis of its unusual properties is the sol-gel fluorination of aluminum alkoxide with anhydrous HF in organic solvents yielding first an amorphous catalytically inactive precursor with high surface area, which can be dried and eventually post-fluorinated to get HS-AlF3. In this thesis, all steps of the synthesis route were thoroughly investigated. The results of these investigations together with detailed analysis of the obtained materials are reported and discussed. HS-AlF3 supported on Al2O3 with different HS-AlF3 loadings was prepared by wet impregnation method. The properties of the HS-AlF3/Al2O3 samples as Lewis acid catalyst were evaluated for CHClF2 dismutation and CBrF2CBrFCF3 isomerization. The preparation of AlFyOx via sol-gel method is also reported. AlFyOx prepared is amorphous and have high surface are up to 240 m2/g.