Thesis (Ph. D.)--University of Florida, 2009. / Title from title page of source document. Document formatted into pages; contains 242 pages. Includes vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Chicago, 1936. / Photolithographed. "Private edition, distributed by the University of Chicago libraries." Bibliography: p. 184-189.

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The reduction of dinitrogen (N2) to ammonia (NH3) will continue to play a vital role in society as the population of the world grows and maintains its dependence on artificial fertilizers. This energy-intensive transformation is achieved industrially by the Haber-Bosch process and naturally via nitrogenase enzymes. Recent synthetic systems attempt to produce NH3 artificially but with lower energy costs than Haber-Bosch by modeling their designs after nitrogenase. This dissertation describes the progress made in one iron-phosphine system, the water-soluble Fe(DMeOPrPE)2N2, capable of producing NH3 at room temperature and pressure. Chapter I describes the history of the coordination chemistry of N2 to a variety of metals, with a focus on iron complexes. In addition to exploring the range of coordination geometries and supporting ligands of such complexes, the application of N2 coordination complexes towards NH3 formation is analyzed. Chapter II discusses the various methods for quantifying yields of ammonia. Along with a historical perspective on the popular indophenol method, the challenges and best conditions for measuring NH3 in the Fe-DMeOPrPE system are defined. Chapter III explores a series of trans-hydrido intermediates along a potential protonation pathway of Fe(DMeOPrPE)2N2. The complete series of reduced dinitrogen ligands (N2, N2H2, N2H4, and NH3) on the Fe(DMeOPrPE)2H+ scaffold is described. Chapter IV highlights the discovery and characterization of a unique bridged Fe(I) dimer, observed during the protonation of Fe(DMeOPrPE)2N2 as a dark purple intermediate. Chapter V describes the electrochemistry of certain intermediates in the Fe-DMeOPrPE system. This insight should open new avenues for future investigations. By altering the electronics of the system, more NH3 may eventually be produced. Chapter VI provides a summary of this work. This dissertation includes previously published and unpublished co-authored material. / 10000-01-01

Submitted by ANA KARLA PEREIRA RODRIGUES (anakarla_@hotmail.com) on 2017-08-09T13:41:39Z No. of bitstreams: 1 arquivototal.pdf: 5544525 bytes, checksum: 9b6efae1c8b35552884ead95fb3851ea (MD5) / Made available in DSpace on 2017-08-09T13:41:39Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 5544525 bytes, checksum: 9b6efae1c8b35552884ead95fb3851ea (MD5) Previous issue date: 2017-02-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this thesis work was carried out a computational study of some reactions forbidden and allowed by spin. The first reaction involves investigated the dissociation of the ligands iron porphyrins ((FeP(L)2, onde, L = H2O, dimethylnitrosamine, Imidazole and Pyridine) and the other concerns the Haber-Weiss mechanism to species such as R-OOH + O2•–, onde R = H, CH3 e CH3CH2. The mechanisms of the both reactions represent a major challenge from the point of view of computational choice of the appropriate method since it involves a large number of stationary points and, in some cases, with different spin multiplicities. For dissociation reactions with Fe-porphyrins were chosen ligands weak and strong field ligands. At this stage we used various DFT methods (OLYP, BP86, oTPSS, M06, M06L, M06L2X, B3PW91, PBE1PBE, B2PLYP e DSD-PBEP86) to estimate the order of spin states for the metal in the form Fe(III) and Fe(II) and some procedures to calculate and potential energy surface of these reactions. The results show that the function of the double-hybrid class DSD-PBEP86 can correctly predict the order of the spin states of the systems studied metalloporphyrin and characterize the crossing of the surfaces of the different spin states during the reaction. The second study the Haber-Weiss reaction with three kinds of peroxides, namely hydrogen peroxide, peroxide and methyl ethyl peroxide. For this problem, we were mapped some mechanisms of reactions that lead to the formation of the products reported in the literature. The reaction of H2O2 with O2•– occurs by two competing reaction channels. The major product (O2 + O•–⋯H2O) follows by a reaction forbidden by spin, while the minor product (H2O⋯O3•–) assumes a reaction allowed by spin. The reaction spin forbidden undergoes intersystem crossing region and the mechanism proves to be governed by the change of the overall electronic configuration during the reaction. In reaction CH3OOH + O2•–, for the first time, is proposed a reaction mechanism and a prediction about the enthalpy of the different reactions that may occur. In the case of the reaction between the methyl, the ethyl peroxide and superoxide is allowed by spin. The computational results of the reaction enthalpy of these reactions are in good agreement with the values found in the literature. / Neste trabalho de tese foi realizado um estudo computacional de algumas reações proibidas e permitidas por spin. A primeira reação investigada envolve a dissociação de ligantes na ferroporfina (FeP(L)2, onde, L = H2O, Dimetil-nitrosamina, Imidazol e Piridina) e a outra diz respeito ao mecanismo de Haber-Weiss para espécies como R-OOH + O2•–, com R = H, CH3 e CH3CH2. Os mecanismos de ambas reações representam um grande desafio do ponto de vista da escolha da metodologia computacional apropriada uma vez que envolvem um grande número de pontos estacionários e, em alguns casos, com diferentes multiplicidades de spin. Para as reações de dissociação com Fe - porfinas foram escolhidos ligantes de campos fraco e forte. Nesta etapa foram utilizados vários métodos da DFT (OLYP, BP86, oTPSS, M06, M06L, M06L2X, B3PW91, PBE1PBE, B2PLYP e DSD-PBEP86) para estimar o ordenamento dos estados de spin para o metal na forma Fe(III) e Fe(II) e alguns procedimentos para calcular e superfície de energia potencial dessas reações. Os resultados mostram que o funcional DSD-PBEP86 consegue prever corretamente o ordenamento dos estados de spin dos sistemas metaloporfirínicos estudados e caracterizar o cruzamento das superfícies dos diferentes estados de spin durante a reação. O segundo estudo trata da reação de Haber-Weiss com três tipos de peróxidos, a saber: peróxido de hidrogênio, metilhidroperóxido e etilhidroperóxido. Para esse problema, foram mapeados alguns mecanismos de reações que levam à formação dos produtos relatados na literatura. A reação do H2O2 + O2•– ocorre por dois canais de reação competitivos. O produto majoritário (O2 + O•–⋯H2O) segue por uma reação proibida por spin, enquanto o produto minoritário (H2O⋯O3•–) assume uma reação permitida por spin. A reação proibida por spin passa por uma região de cruzamento intersistema e o mecanismo mostra ser governado pela mudança da configuração eletrônica total durante a reação. Na reação do CH3OOH com O2•–, pela primeira vez, é proposto um mecanismo de reação e uma previsão acerca da entalpia das diferentes reações que podem ocorrer. No caso da reação entre o metilhidroperóxido, o etilhidroperóxido com o superóxido é do tipo permitida por spin. Os resultados computacionais da entalpia de reação dessas reações estão em boa concordância com os valores encontrados na literatura.

The global demand for nitrogen fertilizer was 12 million metric tonnes in 2014 and is expected to increase to 240 million metric tonnes by the year 2050, with the growth of the global population.  To meet the demand for nitrogen fertilizers, the Haber-Bosch process has primarily been used to produce the precursor of many nitrogen fertilizers - ammonia. The very energy-expensive Haber-Bosch process uses fossil fuels and, therefore, a renewable source of ammonia must be established. Some microorganisms can use atmospheric nitrogen to produce ammonia via the nitrogenase enzyme, a mechanism attractive for alternative ammonia production. In this thesis project, integrating vectors for the marine cyanobacterium Synechococcus PCC 7002 have been designed and generated to facilitate future heterotrophic nitrogenase integration and ammonia production. The vectors were designed for integration in seven neutral sites of the Synechococcus PCC 7002 genome. Five of the seven planned integrating vectors were successfully constructed and transformation was attempted into Synechococcus PCC 7002 to determine the transformation efficiency of the different neutral sites, however, the transformation results were inconclusive.

Ce mémoire propose une étude de la théorie de l’individualité biologique développée par Turner, des problèmes inhérents à celle-ci ainsi qu’une approche qui permet de surmonter les problèmes de la théorie de Turner tout en prenant en compte les aspects importants de cette dernière. Nous montrerons en premier lieu pourquoi, selon Turner, l’individualité est une question écologique et que l’individu ne peut être compris sans ses parties abiotiques si celles-ci jouent un rôle dans la fonctionnalité de l’individu. Par la suite, nous démontrerons que l’approche de Turner est sujette au problème du paradigme développé par Haber. Enfin, en s’inspirant de la théorie de l’individualité de Dupré et O’Malley et de leurs études sur les bactéries, nous forgerons une nouvelle théorie portée sur la fonctionnalité, qualifiée d’approche méréologique, qui surmonte les problèmes exposés tout en prenant en compte le rôle que les parties abiotiques jouent dans le fonctionnement de l’individu. / This master’s thesis consists in a study of the theory of biological individuality developed by Turner, its problems, as well as an approach of individuality that allows us to overcome Turner’s problems while also taking into account the important aspects of his theory. We will start off by showing that, according to Turner, individuality is an ecological matter since an individual cannot be understood without its abiotic parts if the latter play a role in the individual’s functionality. Afterwards we will demonstrate that Turner’s theory is subject to Haber’s problem of the paradigm. Lastly, by building upon Dupré and O’Malley’s theory of individuality and their studies on bacteria, we will develop a new approach focused on functionality, named mereological approach, which overcomes the problems we find in Turner’s theory while also taking into account the role that abiotic parts play in the functionality of individuals.

As Kungsängens wastewater treatment plant is considering a move, it opens up a possibility to implement nitrogen recovery technologies that comply with current and future legislative requirements. Nitrogen recovery offers simultaneous treatment of wastewater and collection of concentrated ammonia products for fertiliser production. This can create a circular and sustainable solution by reduced energy consumption, greenhouse gas emissions and nitrogen pollution. Despite the large amount of research that has been performed on this topic, practical use at wastewater treatment facilities in Sweden are still scarce. The aim of the degree project was to identify nitrogen recovery technologies and investigate their potential impact at a new Kungsängens wastewater treatment plant. A literature review provided different nitrogen technologies and concept scoring was used to rank and score them. Gas permeable membrane and ammonia stripping ranked the highest and both have the potential to be implemented at Kungsängens current or possible new site. Simulations were used to identify the change in energy consumption and change in effluent water quality related to the implementation of a nitrogen recovery technology. Calculations were performed to reach thequantities of nitrogen that could be recovered, and it was found that the nitrogen recovery potential was 0,2343 ton/d using gas permeable membrane, and 0,2750 ton/d using ammonia stripping. By replacing artificial fertilisers with recovered nitrogen, 7,95 kWh/kg N could be saved using gas permeable membrane and 2,76 kWh/kg N could be saved using ammonia stripping. The degree project also provides insight into European and Swedish lawconformity and predictability. Finally, a discussion of environmental impacts, potential for nitrogen recovery, nitrogen policies, and energy savings was conducted. It was concluded that nitrogen recovery can create benefits due to avoided nitrous oxide emissions, avoided production of precipitation chemicals and decreased energy consumption for aeration. Compared to artificial fertiliser produced using the Haber-Bosch method, it was determined that a significant reduction of carbon dioxide emissions could be reached.

Kemisk krigföring i form av luftburna gifter har förekommit i många historiska kontexter. Trots att luftburna gifter, som till exempel giftig rök och gas är likartade företeelser, har inte forskare kunnat enas om äldre former av denna krigföring är jämförbar med den moderna. Huvudorsaken är att deras analyser saknar teoretiska perspektiv som belyser hur respektive   kontexts kemiska förutsättningar påverkar krigföringen. Syftet med den här undersökningen är att jämföra ett modernt nyttjande av luftburna gifter, tyskarnas första klorutsläpp vid Ypres 1915 med ett forntida exempel, den moistiska skolans användande av brandrök som gift under århundradena f. Kr. i Kina. För att kringgå tidigare forsknings problem anläggs ett teoretiskt perspektiv. En teori som belyser dynamiken   mellan kemisk krigföring och respektive kulturs föreställningar om och förhållande till miljön. Undersökningen visar att det är relevant att jämföra det moderna användandet av luftburna gifter med användandet i andra historiska kontexter eftersom det sker i liknande taktiska sammanhang och kräver mycket naturkunskap. Samtidigt belyser analysen att kontexten ger krigföringen en viss karaktär. Moisterna försökte nå framgång genom att samordna och   förbättra den process som gjorde det luftburna giftet effektivt samtidigt som de förlitade sig på generalistkunskap. Tyskarna, däremot förlitade sig på ett så effektivt  kemiskt ämne (agens) som möjligt. För denna typ av krigföring nyttjades utpräglade specialister.   Dessutom var relationen till själva giftet annorlunda i de två kontexterna. Moisterna utsatte sig för röken medan tyskarna avskärmade sig helt från klorgasen. Dessa skillnader går att förstå genom att se hur människorna i respektive kontext utnyttjade den för krigföringen relevanta kemin i icke-militära sammanhang. Den tidigare forskningens problem med att diskutera kemisk krigföring blir också tydligt i undersökningen. Problemet beror på att den vetenskapliga disciplinen kemi medför institutioner och begrepp som begränsar synen på användandet av luftburna gifter. Denna insikt tillsammans med undersökningens övriga resultat belyser något som har relevans för dagens hotbild. Luftburna gifter, kan i rätt sammanhang och genom rätt   prioriteringar göras effektiv utan tillgång till modern vetenskap och industri. Detta bör beaktas när hotbilden från aktörer utan egen militärindustri analyseras. / Airborne poison, as a type of chemical warfare, has been used in many historical contexts. Although airborne poison such as toxic smoke and gas are similar phenomena, researchers have not been able to agree if older forms of warfare are comparable to modern. One reason for this is that their respective analysis lacks theoretical perspectives that account for contextual chemical conditions. The purpose of this study is to compare a modern example of the use of airborne poison, the Germans' first chlorine emissions at Ypres in 1915 with an ancient one, the Mohists use of smoke as a poison in ancient China. A theoretical perspective is applied to circumvent the problems of earlier research. This theory focuses on the dynamics between decision-making in chemical warfare and a particular culture's perception of and relationship to the environment. The study shows that it is relevant to compare the modern use of airborne poison with its use in other historical contexts because the weapon occurs in a similar tactical context. Also this type of warfare requires a lot of knowledge of the natural world. At the same time the analysis illustrates that a specific context gives the warfare a certain character. The Mohists tried to achieve success by coordinating and improving the process by which the airborne poison was made effective. Furthermore they relied on generalist knowledge. The Germans, however, relied on having an efficient chemical substance (agent). For this type of warfare they utilized specialists. The human-poison relationship also differed. The Mohist exposed himself to smoke while the German soldier shut himself off completely from the chlorine gas. These differences can be understood by studying how people exploited similar chemistry in a non-military way  in their respective context. The problems that previous research has had in discussing chemical warfare is also made evident. These problems occur because chemistry as a scientific discipline creates institutions and concepts that limit the view of airborne poison as a weapon. This realization, along with results of the survey in general, illustrates something which has relevance in today’s world. Airborne poison can, in the right place and with the right priorities be effective without modern industrial and scientific resources. This should be considered when analyzing political actors lacking a modern military industry.

This report travels through multiple disciplines to seek innovative and sustainable energy solutions for wastewater treatment plants. The first subject is a report about increased global temperatures and an over-exploitation of natural resources that threatens ecosystems worldwide. The situation is urgent where the current trend is a 2°C increase of global temperatures already in 2040. Furthermore, the energy-land nexus becomes increasingly apparent where the world is going from a dependence on easily accessible fossil resources to renewables limited by land allocation. A direction of the required transition is suggested where all actors of the society must contribute to quickly construct a new carbon-neutral resource and energy system. Wastewater treatment is as required today as it is in the future, but it may move towards a more emphasized role where resource management and energy recovery will be increasingly important. This report is a master’s thesis in energy engineering with an ambition to provide some clues, with a focus on energy, to how wastewater treatment plants can be successfully integrated within the future society. A background check is conducted in the cross section between science, society, politics and wastewater treatment. Above this, a layer of technological insights is applied, from where accessible energy pathways can be identified and evaluated. A not so distant step for wastewater treatment plants would be to absorb surplus renewable electricity and store it in chemical storage mediums, since biogas is already commonly produced and many times also refined to vehicle fuel. Such extra steps could be excellent ways of improving the integration of wastewater treatment plants into the society. New and innovative electric grid-connected energy storage technologies are required when large synchronous electric generators are being replaced by ‘smaller’ wind turbines and solar cells which are intermittent (variable) by nature. A transition of the society requires energy storages, balancing of electric grids, waste-resource utilization, energy efficiency measures etcetera… This interdisciplinary approach aims to identify relevant energy technologies for wastewater treatment plants that could represent decisive steps towards sustainability.