Dissertations / Theses on the topic 'Matthew II'

This study examines ways in which supporters of William III and his opponents used literature to buttress their respective views of government in the wake of the Glorious Revolution. Understanding the polemical character of this art provides more insight both into the literature of the 1690s and into the modes of political debate in the period. As the English people moved from a primarily hereditary view of monarchy at the beginning of the seventeenth century to a more elective view of government in the eighteenth century, the Glorious Revolution proved to be a watershed event. Those favoring James II relied on patriarchal ideas to characterize the new regime as illegitimate, and supporters of the coregent asserted the priority of English and Biblical law to assert that the former king forfeited his right to rule. Chapter one examines three thinkers – Robert Filmer, John Milton, and John Locke – whose thought provides a context for opinions expressed in the years surrounding William of Orange’s ascension to the English throne. In chapter two, John Dryden’s response to James II’s abdication is explored. As the deposed Poet Laureate and a prominent voice supporting of the Stuart line, Dryden sheds light on ways in which Jacobites resisted the authority of the new regime through his response to the Glorious Revolution. Chapter three addresses the work of Thomas Shadwell, who succeeded Dryden as Laureate, and Matthew Prior, whose poetry Frances Mayhew Rippy characterizes as “unofficial laureate verse.” These poets rely on ideas similar to those expressed by Milton and Locke as they seek to validate the events of 1688-1689. The final chapter explores the appropriation of varied conceptions of government in pamphlets and manuscripts written in favor of James II and William III. Focusing on the polemical character of these works from the late 1680s and the 1690s enhances our understanding of the period’s literature and the prominent interaction of politics and writing.

Kapitaltäckningsregler för banker fick ett mer utarbetat regelverk 2007, Basel II. Avsikten med det nya regelverket var att förbättra det tidigare regelverket för både interna och externa aktörer och att fokusera på att säkerställa bankernas risker på ett bättre anpassat sätt efter deras verksamhet. Utvärdering av det nya regelverket har haft ytterst lite fokus på vilka effekter Basel II de facto har haft i praktiken. Då de Europeiska länderna som ingår i G10 nu har följt regelverket drygt två år anser vi att det är möjligt att utvärdera hur de kvantitativa effekterna har satt sina spår i bankernas nyckeltal som mäter lönsamhet och soliditet. Detta har mynnat ut i följande problemformulering och syfte:

 

Har Basel II påverkat bankernas lönsamhet och finansiella ställning?

Studies syfte är att med en kvantitativ metod sätta upp hypoteser för att undersöka om vi finner något samband mellan Basel II och bankernas nyckeltal som en effekt av tiden när Basel II implementerades.

 

Studien utgår från en deduktiv ansats där två möjliga hypoteser var: 1) Att medelvärdet av nyckeltalen ej skiljer sig efter införandet av Basel II år 2007. Det vill säga tiden, och därmed även lagen, har ej haft någon empirisk verkan på nyckeltalet. 2) Att medelvärdet av nyckeltalen skiljer så pass signifikant efter införandet av Basel II att tiden verkar ha haft en empirisk verkan på nyckeltalen. I detta fall skulle lagen mycket väl ha kunnat påverat nyckeltalet. Nyckeltalen som ingick i studien var: Avkastning på eget kapital, Avkastning på investerat kapital, Vinstmarginal, Soliditet, Skuldsättningsgrad, Skuldränta och Tier 1. Urvalet var 49 banker i sju av G-10 länderna. Perioden som undersöktes var 1990-2008. Detta för att få en längre tidsperiod där även flera kriser som kan påverka bankväsendet ingick. Undersökningsmetoden var en regressionsanalys som gjordes för att undersöka om det fanns någon relation mellan Basel II och bankernas nyckeltal som en effekt av tiden. Studien är således en så kallad ”Event studie”.

 

Resultaten visade att för två av nyckeltalen, Avkastning av eget kapital och Vinstmarginal finns en signifikant skillnad efter 2007. Dessa två nyckeltal beskriver lönsamhet vilket kunde förväntas stärkas efter införandet av Basel II. Resultaten i den här studien pekar dock i en annan riktning, lönsamheten verkar ha minskat från 2006-07. Detta kan diskuteras utifrån synpunkten att regelverket är kostsamt att implementera. Studien visar också att övriga nyckeltal inte tycks ha påverkats av införandet av Basel II. Detta kan tyda på att regelverket inte varit så banbrytande som det i vissa fall gjorts gällande.

 

This thesis has two aims. Firstly, in order to answer the question, ‘In what sense do people see Mary as a type of the Church?’, this thesis will set up original typological models of the relationship between Mary and the Church (chapter 1). It will then demonstrate how and why an eschatological element came to be present in these models (chapter 2).It will be a contention of this thesis that looking at the Mario-ecclesial discussions set out in chapters 3 and 4 through these typological models will allow a greater depth of analysis. The models allow one to discern differences between and nuances in various views of the relationship between Mary and the Church that would be impossible to discern if one were using just the language of ‘type’. Secondly the thesis will show how each Mario-ecclesial discussion has been affected by the socio-political context of the time. Specifically, the thesis will analyse the Mario-ecclesial discussions of the patristic, medieval and modern periods in the light of the typological models. In chapter 1, the patristic Mario-ecclesiologies of Irenaeus and Ambrose will be considered. In chapter 2, Bernard of Clairvaux will be used to analyse the eschatological nature of the Mario-ecclesiology in the medieval period. In chapter 3, the contrasting Mario-ecclesiologies of the Second Vatican Council and Hans Urs von Balthasar will be compared. In chapter 4, it will be suggested that John Paul’s model of the Mario-ecclesial relationship was based on his eschatological vision for the Church and the role that Mary plays in that future which is both imminent and already realised. This thesis will demonstrate that by using the typological models in these periods a greater depth of analysis can be achieved. This will be particularly true of the complex and nuanced discussions on Mary in the Roman Catholic Church in the twentieth century. This analysis will culminate in the particular Mariology of John Paul II.

The dark matter search CRESST-II completed its most recent run, Run 32, in 2011. Compared to previous runs, the quantity of data taken in this run increased , significantly. In this work, Oxrop, analysis software in use within the CRESST collaboration, is upgraded to analyse this new data. At the same time, Oxrop's internal structure is improved so that it can now handle data from detectors across different experiments consistently. This upgrade was performed with a view to developing Oxrop's candidacy for use with EURECA, a future dark matter experiment. Oxrop is then used to model CRESST-II data .. First, light detector response to scintillation light produced in y interactions in CRESST -Il' s target crystals is examined. A factor influencing detector efficiency is the time constant of scintillation light production, and this light detector examination is performed with a view to extracting the scintillation time constants of the target crystals. A simple model of light detector response of one exponential rise and two exponential decay times is initially considered. It is shown that this simple model does not closely match the light detector response to y interactions in the crystal scintillator. Empirical extensions to this expected model are then made, allowing for additional decay times. These extensions allow the light detector response to crystal scintillator interactions to be well modelled, and allow estimates of the millikelvin y scintillation time of Ca W04 and Zn W04. This model is then also applied to X-ray interactions directly in the light detectors. It is seen that, even with these model extensions, interactions directly in the light detector still show significant tension with the applied model. This implies that direct calibration of light detectors with X-rays is not possible without a further understanding of light detector response, or that future direct calibrations should be done with optical photons. Position dependent effects in Run 32 calibration data are then studied. A phenomenon that has previously been considered as unrelated to position dependence, the anti-correlation effect between phonon and light detector signals, is shown to exhibit a position dependent effect in at least one lightjphonon detector pair under study. Additionally, the collection efficiency of the light detector is shown to be related to the mean interaction position. Collection efficiency is found to reduce when mean interaction position is close to the cylindrical surfaces of CRESST's Ca W04 target crystals. The magnitude of the difference in light collection: efficiency between surface and bulk interactions is also seen to be correlated with high energy light detector resolution. The WIMP-nucleon cross section limits resulting from the CRESST-II commissioning run (2007) are also reanalysed in this work. The original analysis of the commissioning run accounted only for tungsten recoils in the Ca W04 crystals used in CRESST - II. Here, interactions from calcium and oxygen nuclei are also accounted for. The resulting WIMP-nucleon cross section limits were improved at light WIMP masses -0(10 GeV j c2). These limits show a mild tension with a recent dark matter analysis of Run 32, particularly for WIMP masses below 10 GeV j c2. Possible causes of this tension are discussed

We present new evidence for cross flow and cutting of nonparallel flux lines in type II superconductors. A dramatic reversal is observed in the evolution of $B\sb{z}\sb{hole}$, the axial flux density in the cavity of a hollow cylinder when the magnitude of a helical magnetic field, $\vec H\sb{ext} = \\phi H\sb\phi + \ z H\sb{\rm II}$ is increased or decreased along the surfaces of the specimen. This turn around constitutes a 180$\sp\circ$ degree deviation from the predictions of the "classical" critical state framework (no flux line cutting). Measurements of the concurrent evolution of $\langle B\sb{z}\rangle \sb{wall}$, the axial flux density threading the wall of the hollow cylinder, complement the above data. The behaviour of $\langle B\sb{z}\rangle\sb{wall}$ is also in drastic disagreement with the "classical" picture of "one way" traffic of flux lines dictated solely by the change in magnitude of $\vec H\sb{ext}.$ These observations also provide strong support for our interpretation. Our account of these unexpected phenomena is based on the ideas of two way traffic of sublattices of nonparallel flux lines traversing each other via flux line cutting processes. We briefly review the classical critical state concept. The essential features of the flux cutting process, cross traversal of flux line sheets and attendant "breathing" modes are also outlined. Then the Generalized Critical State Model incorporating a phenomenological framework based on Maxwell's equations, standard physical constraints and two separate energy dissipation mechanisms is summarized. Finally we present our data curves and show in qualitative detail that the observed behaviour demonstrates that flux line cutting occurs and associated breathing in and out of non-parallel flux lines takes place across the surface of type II superconductors subjected to a varying $\vec H\sb{ext}.$

This dissertation describes experimental and theoretical studies of carrier tunneling in semiconductor heterostructures and optical properties of neutron irradiated quantum wells. Unambiguous experimental evidence for the dramatic dependence of hole tunneling rates on in-plane momentum in (Ga,In)As/(Al,In)As asymmetric double quantum wells (ADQWs) is presented. Holes generated near the bandedge tunnel on hundred picosecond time scales, whereas holes excited with large excess energy tunnel on subpicosecond time scales. The mechanism responsible for this increase of three orders of magnitude in the hole tunneling rate is nonresonant delocalization of hole wavefunctions by band mixing in the valence band. The carrier density and temperature dependencies of tunneling dynamics are presented. A simple kinetic model developed for electron LO-phonon assisted tunneling shows good qualitative agreement with experimental data. Exciton tunneling in wide gap, II-VI semiconductors was studied using (Zn,Cd)Se/ZnSe ADQW. The strong Coulomb interaction in II-VI semiconductors makes the tunneling process significantly different from that in III-VI ADQWs. Fast (1 ps) and complete recovery of the narrow well exciton absorption was observed after resonant femtosecond pulse excitation. The observed dynamics contradict the theory of independent electron and hole tunneling. The theory of exciton tunneling was developed. Theoretical analysis shows that tunneling of the exciton as a whole entity with the emission of only one LO-phonon is very slow. Instead, the exciton tunnels via an indirect state in a two-step process whose efficiency is dramatically enhanced by the Coulomb interaction. The optical properties of neutron irradiated GaAs/Ga,Al)As multiple quantum wells are investigated. Sharp room temperature exciton features and a 21 ps carrier lifetime are demonstrated in neutron irradiated multiple quantum wells. Carrier lifetime reduction is consistent with the presence of EL2 defects that are efficiently generated by fast neutrons. The influence of the gamma rays accompanying neutron irradiation is discussed. Neutron irradiation provides a straightforward way to control the carrier lifetime in semiconductor heterostructures with minor deterioration of their excitonic properties.

The annihilation of weakly interacting massive particles (WIMPs), accumulated in gravitational potentials (e.g., the core of the Earth, the Sun or the Galactic halo) would lead to neutrino production. This thesis investigates the possibility of searching for WIMPs in the form of the lightest supersymmetric particle (neutralino) trapped in the Sun using the AMANDA-II neutrino telescope. AMANDA-II is a large Cherenkov detector located deep in the ice at the geographical South Pole. The presented work is based on data taken during the year 2001. An analysis optimized to search for the neutralino-induced flux from the Sun has been developed. The observation of no excess with respect to the expected atmospheric neutrino background has been interpreted as an upper limit on the neutralino annihilation rate in the Sun and on the neutralino-induced muon flux in the vicinity of the detector.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 285-294).
An overwhelming proportion of the universe (83% by mass) is composed of particles we know next to nothing about. Detecting these dark matter particles directly, through hypothesized weak-force-mediated recoils with nuclear targets here on earth, could shed light on what these particles are, how they relate to the standard model, and how the standard model fits within a more fundamental understanding. This thesis describes two such experimental efforts: CDMS 11 (2007-2009) and SuperCDMS Soudan (ongoing). The general abilities and sensitivities of both experiments are laid out, placing a special emphasis on the detector technology, and how this technology has evolved from the first to the second experiment. Some topics on which I spent significant efforts are described here only in overview (in particular the details of the CDMS II analysis, which has been laid out many times before), and some topics which are not described elsewhere are given a somewhat deeper treatment. In particular, this thesis is hopefully a good reference for those interested in the annual modulation limits placed on the low-energy portion of the CDMS II exposure, the design of the detectors for SuperCDMS Soudan, and an overview of the extremely informative data these detectors produce. It is an exciting time. The technology I've had the honor to work on the past few years provides a wealth of information about each event, more so than any other direct detection experiment, and we are still learning how to optimally use all this information. Initial tests from the surface and now underground suggest this technology has the background rejection abilities necessary for a planned 200kg experiment or even ton-scale experiment, putting us on the threshold of probing parameter space orders of magnitude from where the field currently stands.
by Scott A. Hertel.
Ph.D.

The association between natural organic matter (NOM) and iron (Fe) minerals was widely found in soil and sediments and has been shown to impact the fate of Fe minerals and NOM. Ferrihydrite, a ubiquitous Fe mineral, serves as important sink for NOM and rapidly transforms to secondary Fe minerals in the presence of Fe(II). The associated NOM has been found to influence the Fe(II)-catalyzed ferrihydrite transformation pathway, but it remains unclear how various NOM affects this transformation and the implication. This study specifically investigates how different species of NOM affect Fe(II)-catalyzed ferrihydrite transformation under different C/Fe ratios. A series of Fe isotope tracer experiments were conducted to measure Fe atom exchange and electron transfer between aqueous Fe(II) and ferrihydrite in the presence of diverse NOM species. The fate of Ni during Fe(II)-catalyzed transformation of NOM-Fh coprecipitate was also investigated. Ferrihydrite was found less susceptible to Fe(II)-catalyzed transformation with increasing C/Fe ratio and fulvic acids and Suwannee River NOM (SRNOM) in the coprecipitates need lower C/Fe ratio than humic acids to completely inhibit formation of secondary Fe minerals. At C/Fe ratios where ferrihydrite transformed to secondary minerals, goethite was dominant in ferrihydrite coprecipitated with humic acids, whereas lepidocrocite was favored in ferrihydrite coprecipitated with fulvic acids and SRNOM. Adsorbed SRNOM may be more inhibitive than coprecipitated SRNOM on Fe(II)-catalyzed ferrihydrite transformation under similar C/Fe ratios. Despite no secondary mineral transformation at high C/Fe ratios, Mössbauer spectra indicated electron transfer still occurred between Fe(II) and ferrihydrite coprecipitated with fulvic acid and SRNOM. In addition, isotope tracer experiments revealed that a significant fraction of structural Fe(III) in the ferrihydrite mixed with the aqueous phase Fe(II) (~85%). After reaction with Fe(II), Mössbauer spectroscopy indicated some subtle changes in the crystallinity, particle size or particle interactions in the coprecipitate. The effect of coprecipitated SRNOM on Ni(II) distribution during Fe(II)-catalyzed ferrihydrite transformation was investigated with adsorbed Ni(II) and coprecipitated Ni(II). Ni(II) adsorbed on ferrihydrite was more resistant to acid extraction after Fe(II)-catalyzed transformation and suggested that structural incorporation of Ni into secondary Fe minerals occurred. With coprecipitated SRNOM, ferrihydrite did not transform to secondary minerals in the presence of Fe(II) but extensive Fe atom exchange between aqueous Fe(II) and structural Fe(III) still occurred. Limited change in Ni stability was observed, suggesting there was only small portion of Ni redistributed in the presence of Fe(II). Pre-incorporated Ni(II) in Ni-SRNOM-Fh coprecipitate was partially released (6-8 %) in the presence of Fe(II), but the distribution of remaining Ni(II) in the solid did not change measurably. Our observation suggests that the presence of SRNOM limited the redistribution of Ni most likely because of limited transformation of ferrihydrite to secondary minerals.

We have studied samples of CuO and Cu$\sb2$O to pressures of 60 GPa and 35 GPa, respectively, using energy dispersive X-ray diffraction. Samples were studied using a gasketed diamond anvil cell, energy dispersive X-ray diffraction at the Cornell High Energy Synchrotron Source, with a Mo or Al$\sb2$O$\sb3$:Cr$\sp{3+}$ pressure gauge. In the case of Cu$\sb2$O, the two phase transitions, (cubic to hexagonal to another hexagonal) as expected were seen. In CuO no definite phase transition was seen, although indications are given for CuO at 60 GPa converting to a distorted rocksalt-type structure from the initial monoclinic structure. The volume data obtained from the pressure experiments on CuO were best fitted with the third-order Birch-Murnaghan equation of state with B$\sb0$ = 110 GPa and B$\sb0\sp\prime$ = 5.5.

One of the greatest mysteries of the universe that, for the present, puzzles the mind of most astronomers, cosmologists and physicists is the question: "What makes up our universe?". This is due to how a certain substance named Dark Matter came under speculation. It is believed this enigmatic substance, of type unknown, accounts for almost three-quarters of the cosmos within the universe, could be the answer to several questions raised by the models of the expanding universe astronomers have created, and even decide the fate of the expansion of the universe. There is strong observational evidence for the dominance of non-baryonic Dark Matter (DM) over baryonic matter in the universe. Such evidence comes from many independent observations over different length scales. The most stringent constraint on the abundance of DM comes from the analysis of the Cosmic Microwave Background (CMB) anisotropies. In particular, the WMAP (Wilkinson Microwave Anisotropy Probe) experiment restricts the abundance of matter and the abundance of baryonic matter in good agreement with predictions from Big Bang Nucleosynthesis. It is commonly believed that such a non-baryonic component could consist of new, as yet undiscovered, particles, usually referred to as WIMPs (Weakly Interacting Massive Particles). Some extensions of the standard model (SM) of particle physics predict the existence of particles that would be excellent DM candidates. In particular great attention has been dedicated to candidates arising in supersymmetric theories: the Lightest Supersymmetric Particle (LSP). In the most supersymmetric scenarios, the so-called neutralino seems to be a natural candidate, being stable in theories with conservation of R-parity and having masses and cross sections of typical WIMPs. The EDELWEISS collaboration is a direct dark matter search experiment, aiming to detect directly a WIMP interaction in a target material, high purity germanium crystal working at cryogenic temperatures. It relies in the measurement of nuclear recoils that produce measurable effects in the crystal such ionization and heat. My PhD thesis is organized as follows. The first chapter aims to provide an introduction to the theoretical framework and the scientific motivation for the following work. The nature of DM has been one of the most challenging topics in contemporary physics since the first evidences of its existence had been found in the 1930s. Cosmologists and astrophysicists on one side, together with particle theorists on the other have put a lot of effort into this field: I will briefly account for their achievements and for the experimental strategies which can be set in this scenario. Since this thesis work was carried out within the EDELWEISS-II direct dark matter experiment, I will focus the next chapter on this topic, describing the main features. The second chapter is related to the set-up of the EDELWEISS-II, the current stage of the EDELWEISS experiment necessary after a first phase that achieved the best upper limit on the WIMP elastic scattering on nucleon as a function of WIMP mass in 2004. [....]

Cold Dark Matter is believed to constitute almost a quarter of the Universe, most likely in the form of Weakly Interacting Massive Particles (WIMPs), predicted by supersymmetry. This thesis describes the simulation methods, analysis techniques, and results for the calibration of the DRIFT-IIA directional dark matter detector. This is the first module in an array of gas time projection chambers capable of searching for WIMPs with directional sensitivity, localised in the Boulby mine. Analysis of calibration data taken over a period of five months is compared to detailed Monte Carlo simulations using GEANT4, and a number of efficiencies calculated. After simulation and analysis of data taken during neutron source exposures, in a variety of configurations and separated over a number of months, the DRIFT-IIA detector is found to have an efficiency of 94±2(stat)±5(sys)% for the detection of neutron-induced nuclear recoils. This efficiency is reduced to 44±1(stat)±5(sys)% when measures are taken to remove background events from all data, and a remaining population of events from radon progeny recoils is discussed. The gamma ray rejection factor is determined to be better than 10^-5 following similar analysis of data taken during gamma ray source exposures. Neutron and gamma ray flux from rock surrounding the detector is calculated and interaction rates as a result of this radioactivity in an un-shielded DRIFT-IIA found to be 1.3 nuclear recoils per day and under 2.1 electron recoils per day, above detector threshold, with the nuclear recoil rate dropping to under 1 event per year for a shielded detector. Future operation, development and expansion of the DRIFT-II array will lead to increased potential for directional dark matter detection.

Many workers visualize that, when magnetic flux first penetrates into type II superconductors, the flux line lattice exhibits a discontinuity of magnitude comparable to the lower critical field $H\sb{c1}$ over a dimension of the order of the penetration depth $\lambda$ along the front of the invading flux line lattice. This discontinuity is referred to as the dB/dH effect in the literature. Such a discontinuity is also thought to exist in the magnetic flux configuration (B profile) at the periphery of the specimen when the applied magnetic field $H\sb{a}$, which caused the flux lines to enter the specimen, is then removed. We have compared $\langle B\rangle\sb{rem}$, the amount of magnetic flux trapped in a sample after it has been subjected to an excursion (half cycle) of $H\sb{a}$ with $\langle B\rangle\sb{in}$, the amount of flux permeating the specimen at the peak of a half cycle of $H\sb{a}$. Such measurements were performed on six conventional type II superconductors in the form of long solid cylinders and ribbons. These observations are compared with critical state model predictions which incorporate discontinuities in the B profile of various magnitude ranging from zero to $B\sb{c1}$ and beyond. We show that the presence of any such discontinuities will be dramatically evident in graphs of $\langle B\rangle\sb{rem}$/ $\langle B\rangle\sb{in}$ versus $\langle B\rangle\sb{in}$. Plots of the data in this format indicate quite clearly that discontinuities are not present.

Formulae for the magnetic moment $\vec\mu$ of anisotropic platelets of high $T\sb{c}$ superconductors developed by Gyorgy et al and Peterson are frequently exploited by these and other researchers to estimate $j\sbsp{c}{c}$ and $j\sbsp{c}{ab}$, the critical current densities along the c axis and in the ab plane taken to be independent of the magnetic flux density B. These formulae were derived using the basic definition, $\ = ( -\ \mu\sb0H\sb{a})/\mu\sb0$ and ignoring end effects, (i.e. any demagnetizing fields), hence implied that the aspect ratio along the magnetizing field $H\sb{a}$ is large. This approximation is inappropriate for platelets penetrated by $H\sb{a}$. We develop these formulae using the alternative basic definition of a magnetic moment, $\vec\mu = 1/2\int(\vec{R}\times \vec{j})dV$. Now however, for the approach to be valid, $\vec{j} = j\sbsp{c}{c}$ or $\vec{j} = j\sbsp{c}{ab}$ must be independent of B (Bean approximation) and fill the entire volume of the specimen (i.e. a saturated critical state must be established). We show that these formulae are correct under these restrictions regardless of the configuration of $\vec{B}(x,y,z)$ and the neglect of end effects and attendant demagnetizing fields. Pursuing this framework and the latter definition we develop formulae for $\vec\mu$ for isotropic parallelepipeds of various aspect ratios as a function of their inclination $\theta$ with respect to the magnetizing field $\vec H\sb{a}$. We maintain throughout the critical assumption that the induced persistent currents circulate transverse to $\vec H\sb{a}$. The graphs of computations with these formulae are useful in identifying the role of geometry on the magnitude of $\vec\mu$. We also envisage two simple but basic regimes of anisotropy of the critical current densities. (Abstract shortened by UMI.)

The biggest question in astrophysics and cosmology today is identifying the composition of the Universe. Approximately 25% is thought to be comprised of dark matter, particles that lie outside of the standard model of particle physics and have such a low cross section that they have to date evaded detection despite the substantial indirect observational evidence. DRIFT-II is one of about two dozen experiments designed to directly detect dark matter in the laboratory. Dark matter particles, through an elastic nuclear recoil, should create ionisation tracks in the detector. A positive signal would be the identification of a number of dark matter events that have an anisotropic distribution of recoil directions peaked in the direction of solar motion. The work presented here is a detailed analysis of the data from the DRIFT-lIb experiment and includes event discrimination and techniques for two and three dimensional track reconstruction. The expected dark matter event rate given the latest experimental results is calculated for this particular experiment with a result of 8.6 . 10-3 events per kg·day. The lower energy resolution limit of the detector is measured as 1.23 keV for an electron recoil and 3.46 keV for a sulphur nucleus recoil. Simulations of the particle interactions expected in the detector are performed and applied to experimental data. A full analysis of the directional sensitivity of the detector is also presented. Finally, a dark matter exclusion limit is calculated from experimental data to be 6.9 10-2 pb for a WIMP mass of 100 GeV/c2

The internal magnetic field distributions for a type II superconductor (a single crystal YBa2Cu3O7-delta ) with large normal inclusions (YBa2Cu3O 7-delta) are studied. A model based on the London Equations has been successfully developed and applied to the interpretation of the pSR data on this system. In our model, these inclusions are assumed to be cylindrical in shape and infinite in length. Therefore, this model should be especially appropriate for the prediction of field distributions in single crystal superconductors in which columnar defects have been purposely introduced to enhance pinning.;muSR experiments on a large single-crystal sample of YBa2C u3O7-delta with non-conducting YBa2Cu3 O7-delta inclusions show some interesting characteristics, especially the magnetic field distribution in the inclusion regions. In our model, the difference between the field value in the inclusions and the value at the saddle point is sensitive to the penetration depth. Comparing the calculated to observed field differences provides a new method for determining the penetration depth.

The LHC at CERN is now undergoing a set of upgrades to increase the center of mass energy for the colliding particles to be able to explore new physical processes. The focus of this thesis lies on the so called phase II upgrade which will preliminarily be completed in 2023. After the upgrade the LHC will be able to accelerate proton beams to such a velocity thateach proton has a center of mass energy of 14 TeV. One disadvantage of the upgrade is that it will be harder for the atlas detector to isolate unique particle collisions since more and more collisions will occur simultaneously, so called pile-up. For 14 TeV there does not exist a full simulation of the atlas detector. This thesis instead uses data from Monte Carlo simulations for the particle collisions and then uses so called smearing functions to emulate the detector responses. This thesis focuses on how a mono-jet analysis looking for different wimp models of dark matter will be affected by this increase in pile-up rate. The signal models which are in focus are those which try to explain dark matter without adding new theories to the standard model or QFT, such as the effective theory D5 operator and light vector mediator models. The exclusion limits set for the D5 operators mass suppression scale at 14 TeV and 1000 fb-1are 2-3 times better than previous results at 8 TeV and 10 fb-1. For the first time limits have been set on which vector mediator mass models can be excluded at 14 TeV.

The model of Clem and Hao and others is extended to account for the enhancement of the Meissner effect observed in single crystals of hysteretic type II superconductors upon thermal cycling below Tc in static applied magnetic fields. Predictions are made about the features of the final closed thermal hysteretis loop achievable by extensive cycling and their dependence on the temperature limits T1 and T2 < Tc chosen for the cycles. A large variety of observations, by several workers, of a narrow peak of enhanced Meissner effect near Tc in polycrystalline type II superconductors upon slow warming in static applied fields after fast field cooling, are qualitatively and quantitatively accounted for by a model where we introduced the scheme developed above for single crystals into a weak-linked intergranular network (matrix). This "two tier" framework is then extended to describe the enhancement of the Meissner effect observed by Hyun by thermal cycling of weak-linked Nb3Sn below Tc in a static field. A simple framework is presented which quantitatively develops the proposal of Evetts and Glowacki that the superposition of the applied field H a and the return field, Hr of the magnetized grains, is the cause of the hysteretic behaviour of Ic in weak-linked high T c superconductors and the occurrence of a peak in Ic versus Ha descending and reascending, after an excursion to various values, denoted Hcycle, or after field cooling in different H cool. Observations by several workers on the dependence, of the position of four categories of peaks of Ic, on Hcycle and Hcool are reproduced by this model and yield estimates of the "compression" factor C in the linear dipole approximation, H r = C Mg. We also show that, ratios of the measured plateau values for the position of these peaks, lead to an estimate for C which is independent of H·g, the penetration field into the grains, and of the model chosen to calculate the dependence of the magnetization of the grains, Mg, on Ha. Instead of the artificial pseudo-Josephson - junction expression generally used by other workers in the analysis of Ic hysteresis phenomena, we develop a family of formulae based on the critical state concept applied to idealized planar geometry. Exploiting an especially simple case from this family of formulae we reproduce a panoply of experimental curves of Ic versus Ha displayed in the literature and exhibiting a variety, of features. Analysis of the extensive data of List et al reveals that our approach leads to results in accord with observations whereas the Josephson junction format does not. (Abstract shortened by UMI.)

Ce travail porte sur l'étude d'hétérostructures de semiconducteurs II-VI à alignement de bandes de type II, en particulier sous forme de superréseaux. Il s'agit d'un système prometteur pour une application photovoltaïque, et c'est dans cette optique qu'est orienté ce travail. Une première partie traite ainsi d'une réflexion conceptuelle sur l'apport des interfaces de type II au photovoltaïque. La deuxième partie porte sur l'étude de la croissance de CdSe et ZnTe par épitaxie par jets moléculaires, sur différents substrats. Ces matériaux sont particulièrement intéressants et adaptés pour cette application car ils ont un gap direct, quasiment le même paramètre de maille, un alignement de bandes de type II, et le CdSe une bande interdite compatible avec le spectre solaire. De plus une structure basée sur un superréseau très courte période de ces matériaux permet de créer un absorbeur solaire aux propriétés modulables, qui peut s'approcher de l'absorbeur idéal, avec des contacts intrinsèquement adaptés. En contrepartie il s'agit de semiconducteurs binaires qui n'ont aucun atome en commun, de sorte que la croissance d'échantillons avec des épaisseurs précises à la monocouche près constitue un vrai défi. Pour cette raison nous avons procédé à une étude fine des interfaces grâce à des analyses de diffraction de rayons X et de microscopie en transmission, qui nous permet de conclure sur la nature chimique des atomes à proximité des interfaces. Vient ensuite une étude poussée de spectroscopie sur les effets des interfaces de type II sur les porteurs de charges, à travers leur énergie et cinétique de recombinaison. Nous avons développé un modèle analytique qui permet d'ajuster précisément toutes les caractéristiques observées en relation avec ces interfaces, et qui témoigne d'un mécanisme de séparation des charges très efficace. Nous montrons par la suite que ces effets observés sont des caractéristiques intrinsèques de toutes les interfaces de type II, indépendamment des matériaux et des structures, et que ceux-ci nous permettent d'extraire avec précision les valeurs des décalages de bandes entre différents matériaux à alignement de type II. Le dernier chapitre traite finalement du développement de cellules photovoltaïques basées sur les concepts étudiés dans cette thèse. Il aborde notamment les structures de dispositifs envisagées ainsi que nos premiers résultats de rendements de cellules basées sur des hétérostructures de semiconducteurs avec cet alignement de bandes.

The emergence of semiconducting nanowires as the new building blocks for photovoltaic (PV) devices has drawn considerable attention because of the great potential of achieving high efficiency and low cost. In special, nanowires with a coaxial structure, namely, core-shell structures have demonstrated significant advantages over other device configurations in terms of radial charge collection and cost reduction. In this dissertation, several core-shell nanowire structures, including ZnO/ZnSe, ZnO/ZnS, and CdSe/ZnTe, have been synthesized and the photovoltaic devices processed from a ZnO/ZnS core-shell nanowire array and a single CdSe/ZnTe core-shell nanowire have been demonstrated. By combining the chemical vapor deposition and pulsed laser deposition (PLD) techniques, type-II heterojunction ZnO/ZnSe and ZnO/ZnS core-shell nanowire array were synthesized on indium-tin-oxide substrates. Their structures and optical properties have been investigated in detail, which revealed that, despite highly mismatched interfaces between the core and shell, both systems exhibited an epitaxial growth relationship. The quenching in photoluminescence but enhancement in photocurrent with faster response upon coating the core with the shell provides the evidence that the charge separation and collection in the type II core-shell nanowire is greatly improved. This demonstration brings much greater flexibility in designing next generation PV devices in terms of material selection and device operation mechanisms for achieving their maximum energy conversion efficiencies at a low cost and in an environmentally friendly manner. In order to achieve a high quality interface in the core-shell nanowire, CdSe and ZnTe, which have close lattice parameters and thermal expansion coefficients, were chosen to fabricate nanowire solar cells. ZnTe and CdSe nanowires were first synthesized by thermal evaporation and the shells were subsequently deposited by PLD. ZnTe/CdSe nanowires represented an inhomogeneous coating while the CdSe/ZnTe core-shell exhibited a conformal coating with obvious ZnTe eptilayer. The final PV device based on an individual CdSe/ZnTe nanowire demonstrated an efficiency of ~1.7%. In addition, a controllable synthesis of CdSe nanowire array on muscovite mica substrate was presented, providing the possibility to harvest hybrid energies in an all-inorganic nanowire array.

L’analyse de la réponse du lecteur (reader-response) est une théorie littéraire qui étudie la réception d’oeuvres littéraires et le rôle du lecteur dans leur interprétation. Inspirée par la version postformaliste de la stylistique affective de Stanley Fish et par l’adaptation de cette méthode pour l’étude de la littérature biblique de Robert Hurley, cette thèse passe des lecteurs théoriques (implicite, modèle, idéal...) aux « lecteurs réels » pour analyser les effets du récit des origines de Jésus en Mt 1-2. Quels sont les effets ressentis lors de la lecture de Mt 1-2 ? Par une approche méthodologique novatrice, cette thèse répondra à cette question en décrivant les effets de ce texte dans une lecture au ralenti. Le texte comme objet d’analyse cède la place à la lecture comme un processus se déroulant dans le temps avec une attention à la tension ressentie par le jeu du suspense, de la curiosité et de la surprise. La description de l’expérience de lecture montre les transformations produites au moment même où le lecteur redonne présence concrète au texte par son acte interprétatif. Le ralentissement de la lecture permet de souligner la présence de dispositifs textuels qui demandent une implication active du lecteur tels que l’ironie, la métaphore et les textes autophages. Polysémique, Mt 1-2 a permis une grande diversité de réponses chez ses lecteurs. Les nombreux espaces d’indétermination du texte ont généré diverses expériences de lecture. Parmi les éléments ambigus explorés, on retrouve : la présence de cinq femmes dans une généalogie patriarcale (1,1- 16), un décompte du nombre de générations (1,17) différent de la liste d’engendrements (1,2-16), la discontinuité généalogique entre Joseph et Jésus (1,16), la « justice » équivoque de Joseph (1,19), la nature de l’astre que suivent les mages (2,2.9) et la citation « Ναζωραῖος κληθήσεται » qui n’a aucun référent connu (2,23). Cette recherche montre un éclatement des interprétations au sujet de ces questions. Au lieu de combler les apories textuelles, cette thèse propose de regarder les réponses des « vrais lecteurs » que sont les Pères de l’Église et les exégètes du XIXe au XXIe siècle. Leurs écrits sont des réponses au texte lu. Ces réponses sont présentées non pas pour trouver la meilleure interprétation, mais pour comprendre l’effet de la lecture du texte sur ces lecteurs. En tablant sur les effets produits par le texte, il appert que dès les premiers versets, l’Évangile selon Matthieu cherche à dérouter ses lecteurs pour les préparer à lire un récit déconcertant. Telle une énigme, la généalogie désoriente ses lecteurs pour mieux les guider dans leur quête de Jésus et de ses origines. Mt 1,1-17 subvertit le messianisme davidique en revisitant l’histoire d’Israël pour proposer l’identité de Jésus comme messie à la fois issu de David et différent de lui. L’attention aux masculinités de ses personnages fait partie des aspects novateurs de cette thèse. Alors que la plupart des études ne font qu’effleurer le contexte vétérotestamentaire des cinq citations du récit autour des origines de Jésus (1,18-2,23), cette thèse propose d’analyser les effets de l’interaction entre le contexte narratif en Matthieu et les contextes narratifs des oeuvres citées. De manière originale, ces citations sont présentées comme des métalepses qui en quelques mots, incitent les lecteurs à penser au monde narratif complet d’où ils sont tirés. Cette pratique s’oppose à la stratégie interprétative habituelle qui voit ces citations comme des « mots crochets » au sein d’un modèle interprétatif centré sur la prédiction et l’accomplissement de paroles prophétiques. Les résultats de cette étude intertextuelle soulignent que l’accomplissement de ces citations porte aussi un rapport de renversement. L’étude des lecteurs inscrits ne permet pas de comprendre la richesse de l’expérience de la lecture. Le rôle du lecteur réel comme créateur de sens a été sous-estimé en études bibliques. Le dialogue entre lecteurs présenté dans cette thèse souligne la pluralité interprétative. Il permet de découvrir les effets du récit des origines de Jésus en Mt 1-2 par les rapports possibles entre ce texte et ses lecteurs.
L’analyse de la réponse du lecteur (reader-response) est une théorie littéraire qui étudie la réception d’oeuvres littéraires et le rôle du lecteur dans leur interprétation. Inspirée par la version postformaliste de la stylistique affective de Stanley Fish et par l’adaptation de cette méthode pour l’étude de la littérature biblique de Robert Hurley, cette thèse passe des lecteurs théoriques (implicite, modèle, idéal...) aux « lecteurs réels » pour analyser les effets du récit des origines de Jésus en Mt 1-2. Quels sont les effets ressentis lors de la lecture de Mt 1-2 ? Par une approche méthodologique novatrice, cette thèse répondra à cette question en décrivant les effets de ce texte dans une lecture au ralenti. Le texte comme objet d’analyse cède la place à la lecture comme un processus se déroulant dans le temps avec une attention à la tension ressentie par le jeu du suspense, de la curiosité et de la surprise. La description de l’expérience de lecture montre les transformations produites au moment même où le lecteur redonne présence concrète au texte par son acte interprétatif. Le ralentissement de la lecture permet de souligner la présence de dispositifs textuels qui demandent une implication active du lecteur tels que l’ironie, la métaphore et les textes autophages. Polysémique, Mt 1-2 a permis une grande diversité de réponses chez ses lecteurs. Les nombreux espaces d’indétermination du texte ont généré diverses expériences de lecture. Parmi les éléments ambigus explorés, on retrouve : la présence de cinq femmes dans une généalogie patriarcale (1,1- 16), un décompte du nombre de générations (1,17) différent de la liste d’engendrements (1,2-16), la discontinuité généalogique entre Joseph et Jésus (1,16), la « justice » équivoque de Joseph (1,19), la nature de l’astre que suivent les mages (2,2.9) et la citation « Ναζωραῖος κληθήσεται » qui n’a aucun référent connu (2,23). Cette recherche montre un éclatement des interprétations au sujet de ces questions. Au lieu de combler les apories textuelles, cette thèse propose de regarder les réponses des « vrais lecteurs » que sont les Pères de l’Église et les exégètes du XIXe au XXIe siècle. Leurs écrits sont des réponses au texte lu. Ces réponses sont présentées non pas pour trouver la meilleure interprétation, mais pour comprendre l’effet de la lecture du texte sur ces lecteurs. En tablant sur les effets produits par le texte, il appert que dès les premiers versets, l’Évangile selon Matthieu cherche à dérouter ses lecteurs pour les préparer à lire un récit déconcertant. Telle une énigme, la généalogie désoriente ses lecteurs pour mieux les guider dans leur quête de Jésus et de ses origines. Mt 1,1-17 subvertit le messianisme davidique en revisitant l’histoire d’Israël pour proposer l’identité de Jésus comme messie à la fois issu de David et différent de lui. L’attention aux masculinités de ses personnages fait partie des aspects novateurs de cette thèse. Alors que la plupart des études ne font qu’effleurer le contexte vétérotestamentaire des cinq citations du récit autour des origines de Jésus (1,18-2,23), cette thèse propose d’analyser les effets de l’interaction entre le contexte narratif en Matthieu et les contextes narratifs des oeuvres citées. De manière originale, ces citations sont présentées comme des métalepses qui en quelques mots, incitent les lecteurs à penser au monde narratif complet d’où ils sont tirés. Cette pratique s’oppose à la stratégie interprétative habituelle qui voit ces citations comme des « mots crochets » au sein d’un modèle interprétatif centré sur la prédiction et l’accomplissement de paroles prophétiques. Les résultats de cette étude intertextuelle soulignent que l’accomplissement de ces citations porte aussi un rapport de renversement. L’étude des lecteurs inscrits ne permet pas de comprendre la richesse de l’expérience de la lecture. Le rôle du lecteur réel comme créateur de sens a été sous-estimé en études bibliques. Le dialogue entre lecteurs présenté dans cette thèse souligne la pluralité interprétative. Il permet de découvrir les effets du récit des origines de Jésus en Mt 1-2 par les rapports possibles entre ce texte et ses lecteurs.
Reader-response is a literary theory which studies the reception of literary works and the role of the reader in their interpretation. Inspired by Stanley Fish’s post-formalist version of affective stylistics and Robert Hurley’s adaptation of that method for the study of biblical literature, this thesis shifts attention from the responses of theoretically constructed readers (implicit, model, ideal…) to the responses of a “real reader” to the narrative of the origins of Jesus in Matt. 1-2. What effects does Matt. 1-2 produce? This research question is answered by using an innovative methodological approach: the author describes what happens as one slows down the reading event, reporting on the effects produced by each successive word, phrase and sentence. The “text as object” dissolves in a dynamic reading experience which takes place in time, generating suspense, curiosity and surprise. The description of the reading experience shows the transformations produced at the very moment the reader gives concrete expression to the text by his interpretive act. Slowing down the reading process brings the essential, active role of the reader into view in the operation of such textual devices and strategies as irony, metaphor and the self-consuming artifact. Historically, the great diversity of reading experiences recorded in successive exegeses may partially be explained by the many gaps of Matt. 1-2. Among the ambiguous elements explored are: the presence of five women in a patriarchal genealogy (1:1-16), the number of generations (1:17) that is different from the list of generations (1:2-16), the genealogical discontinuity between Joseph and Jesus (1:16), the equivocal "justice" of Joseph (1:19), the nature of the star followed by the magi (2:2,9), and the quotation "Nαζωραῖος κληθήσεται" which has no known source (2:23). A review of available research underscores the considerable confusion that this text has stirred up. Instead of filling in textual aporias, this thesis proposes to look at the answers of the "real readers" that are Church Fathers and exegetes of the twentieth and twenty-first centuries. Their writings are responses to the textual devices of the read text. These responses are not presented with a view to finding the one right interpretation, but in order to understand the effects this text produces in readers. Based on the effects produced by the text, it appears that from the first verses, the Gospel according to Matthew seeks to disorient its readers, preparing them for the disconcerting narrative that follows. Like an enigma, the genealogy throws its readers off balance as they begin their quest for Jesus and his origins. Matt. 1:1-17 subverts Davidic messianism by revisiting the history of Israel to propose Jesus as a Messiah, both from David and different from him. One of the innovative aspects of this thesis is to pay attention to the ways in which these male characters express their masculinities. While most studies merely scratch the context of the Old Testament quoted in Matt. 1:17-2:23, this thesis proposes to analyze the effects of the interaction between the narrative context in Matthew and the narrative contexts of the works cited. In an original way, these quotations are presented as metalepses. Using a few words, they encourage readers to think of the complete narrative world from which these words are drawn. This procedure is contrary to the usual interpretative strategy which treats these quotations as "hook words" within an interpretive model centered on the prediction and fulfillment of prophecies. The results of this intertextual study underscores the fact that the relationship between text and intertext modifies our understanding of both. Studies which concentrate on the “inscribed reader” do not to justice to the richness of the reading experience. The role of the real reader as a creator of meaning has been underestimated in biblical studies. The dialogue between real readers, past and present, emphasizes the interpretative plurality that makes it possible to discover the effects of the story of the origins of Jesus in Matt. 1-2, highlighting some of the possible relations between this text and reader.
Reader-response is a literary theory which studies the reception of literary works and the role of the reader in their interpretation. Inspired by Stanley Fish’s post-formalist version of affective stylistics and Robert Hurley’s adaptation of that method for the study of biblical literature, this thesis shifts attention from the responses of theoretically constructed readers (implicit, model, ideal…) to the responses of a “real reader” to the narrative of the origins of Jesus in Matt. 1-2. What effects does Matt. 1-2 produce? This research question is answered by using an innovative methodological approach: the author describes what happens as one slows down the reading event, reporting on the effects produced by each successive word, phrase and sentence. The “text as object” dissolves in a dynamic reading experience which takes place in time, generating suspense, curiosity and surprise. The description of the reading experience shows the transformations produced at the very moment the reader gives concrete expression to the text by his interpretive act. Slowing down the reading process brings the essential, active role of the reader into view in the operation of such textual devices and strategies as irony, metaphor and the self-consuming artifact. Historically, the great diversity of reading experiences recorded in successive exegeses may partially be explained by the many gaps of Matt. 1-2. Among the ambiguous elements explored are: the presence of five women in a patriarchal genealogy (1:1-16), the number of generations (1:17) that is different from the list of generations (1:2-16), the genealogical discontinuity between Joseph and Jesus (1:16), the equivocal "justice" of Joseph (1:19), the nature of the star followed by the magi (2:2,9), and the quotation "Nαζωραῖος κληθήσεται" which has no known source (2:23). A review of available research underscores the considerable confusion that this text has stirred up. Instead of filling in textual aporias, this thesis proposes to look at the answers of the "real readers" that are Church Fathers and exegetes of the twentieth and twenty-first centuries. Their writings are responses to the textual devices of the read text. These responses are not presented with a view to finding the one right interpretation, but in order to understand the effects this text produces in readers. Based on the effects produced by the text, it appears that from the first verses, the Gospel according to Matthew seeks to disorient its readers, preparing them for the disconcerting narrative that follows. Like an enigma, the genealogy throws its readers off balance as they begin their quest for Jesus and his origins. Matt. 1:1-17 subverts Davidic messianism by revisiting the history of Israel to propose Jesus as a Messiah, both from David and different from him. One of the innovative aspects of this thesis is to pay attention to the ways in which these male characters express their masculinities. While most studies merely scratch the context of the Old Testament quoted in Matt. 1:17-2:23, this thesis proposes to analyze the effects of the interaction between the narrative context in Matthew and the narrative contexts of the works cited. In an original way, these quotations are presented as metalepses. Using a few words, they encourage readers to think of the complete narrative world from which these words are drawn. This procedure is contrary to the usual interpretative strategy which treats these quotations as "hook words" within an interpretive model centered on the prediction and fulfillment of prophecies. The results of this intertextual study underscores the fact that the relationship between text and intertext modifies our understanding of both. Studies which concentrate on the “inscribed reader” do not to justice to the richness of the reading experience. The role of the real reader as a creator of meaning has been underestimated in biblical studies. The dialogue between real readers, past and present, emphasizes the interpretative plurality that makes it possible to discover the effects of the story of the origins of Jesus in Matt. 1-2, highlighting some of the possible relations between this text and reader.

Iron (Fe) speciation is important for many biogeochemical processes. The high abundance and limited solubility of Fe(III) are responsible for the widespread occurrence of Fe(III) minerals in the environment. Co-precipitation and adsorption onto mineral surfaces limits the free concentrations of compounds such as arsenate (As(V)), Fe(III) and, phosphate (P(V)). Mineral dissolution, on the other hand, might lead to elevated concentrations of these compounds. Fe speciation is strongly affected by natural organic matter (NOM), which suppresses hydrolysis of Fe(III) via complexation. It limits the formation of Fe(III) minerals and Fe(III) co-precipitation. This thesis is focused on interactions between Fe(III) and NOM as well as their impact on other elements (i.e. As(V) and P(V)). X-ray absorption spectroscopy (XAS) was used to obtain molecular scale information on Fe and As speciation. This was complemented with infrared spectroscopy, as well as traditional wet-chemical analysis, such as pH and total concentration determinations. Natural stream waters, soil solutions, ground water and soil samples from the Krycklan Catchment, in northern Sweden, were analyzed together with model compounds with different types of NOM. A protocol based on ion exchange resins was developed to concentrate Fe from dilute natural waters prior to XAS measurements. Iron speciation varied between the stream waters and was strongly affected by the surrounding landscape. Stream waters originating from forested or mixed sites contained both Fe(II, III)-NOM complexes and precipitated Fe(III) (hydr)oxides. The distribution between these two pools was influenced by pH, total concentrations and, properties of NOM. In contrast, stream waters from wetland sites and soil solutions from a forested site only contained organically complexed Fe. Furthermore, the soil solutions contained a significant fraction Fe(II)-NOM complexes. The soil samples were dominated by organically complexed Fe and a biotite-like phase. Two pools of Fe were also identified in the ternary systems with As(V) or P(V) mixed with Fe(III) and NOM: all Fe(III) was complexed with NOM at low total concentrations of Fe(III), As(V) and/or P(V). Hence, Fe(III) complexation by NOM reduced Fe(III)-As(V)/P(V) interactions at low Fe(III) concentrations, which led to higher bioavailability. Exceeding the Fe(III)-NOM complex equilibrium resulted in the occurrence of Fe(III)-As(V)/P(V) (co-)-precipitates.

The mining of sulphidic ore to extract metals such as zinc and copper produces huge quantities of waste material. The weathering and oxidation of the waste produces what is commonly known as Acid Mine Drainage (AMD), a dilute sulphuric acid rich in Fe(II) and heavy metals. This thesis serves to summarise five papers reporting how the precipitation of Fe(III) phases can attenuate the contamination of heavy metals by adsorption processes.

Schwertmannite (Fe8O8(OH)6SO4) is a common Fe(III) mineral precipitating in AMD environments at pH 3-4. The stability and surface chemistry of this mineral was investigated. It was shown that the stability depended strongly on pH and temperature, an increase in either promoted transformation to goethite (α-FeOOH). Two pH dependent surface species of SO42- were detected with infrared (ATR-FTIR) spectroscopy.

The adsorption of Cu(II), Pb(II) and Zn(II) to schwertmannite occurred at lower pH than to goethite, whereas Cd(II) adsorption occurred in a similar pH range on both schwertmannite and goethite. Extended x-ray absorption fine structure (EXAFS) spectroscopy suggests two surface species for Cu(II) and Cd(II) at the schwertmannite surface. Cu(II) adsorbs monodentately and Cd(II) bridging bidentately to adsorbed SO42-. Both metal ions also adsorb in a bridging bidentate mode to the surface hydroxyl groups. At pH 7.5 up to 2.7 μmol Cd(II) m-2 could be adsorbed to schwertmannite, indicating a large adsorption capacity for this mineral.

The acid-base properties of two NOM samples were characterised and could be well described as diprotic acids below pH 6. The adsorption of NOM to schwertmannite and goethite was very similar and adsorption occured in a very wide pH range.

High concentrations of NOM increased the adsorption of Cu(II) to goethite at low pH whereas a slight decrease was noted at low concentrations of NOM. No effect was detected in the schwertmannite system.

The formation of Fe(III) phases from precipitation of AMD was shown to be very pH dependent. At pH 5.5 a mixture of minerals, including schwertmannite, formed whereas at pH 7 only lepidocrocite (γ-FeOOH) formed. The concentration of Zn(II) in AMD could by adsorption/coprecipitation be reduced to environmentally acceptable levels.

Le devenir des anciens sites miniers est un sujet de préoccupation sociétale. Afin de garantir la protection de l'écosystème ainsi qu'un impact radiologique minimal sur la biosphère, il est important de comprendre les paramètres qui régissent la migration de l'uranium (et de ses produits de désintégration, en particulier le radium 226) et d'être capable de le modéliser. Dans la nature, parmi les phases qui peuvent retenir 238U(VI) et 226Ra(II), la tourbe est connue pour avoir une forte affinité pour l'uranium VI. La tourbe sèche étant généralement composée à près de 90% de matière organique, l'objectif de cette étude est de qualifier et de quantifier la capacité d'adsorption et de désorption de la matière organique de la tourbe pour 238U(VI) et 226Ra(II). Les échantillons de tourbe prélevés à proximité de l'ancien site d'extraction d'uranium des Sagnes (Limousin, France) ont été caractérisés et ont ensuite été utilisés pour des expériences d'adsorption et de désorption en btach. Les résultats montrent que l'adsorption de 226Ra(II) sur la tourbe est supérieure à 97% pour pH>4-6 (suivant la teneur en particules détritiques dans la tourbe), ce qui correspond à des valeurs de Kd de 4500 pour 500mL/g. Quand à elle, l'adsorption de 238U(VI) est supérieure à 80% à pH>3, avec des valeurs de Kd qui atteignent 11000 mL/g vers pH 4.5. La désorption mesurée après un mois reste très faible. Contrairement aux tourbes classiques, la tourbière des Sagnes présente la particularité d'avoir une charge détritique importante (jusqu'à 50% de la masse de la tourbe sèche). L'interprétation des courbes de rétention de 238U(VI) et 226Ra(II) nécessite au préalable de discriminer à l'aide de modélisations, la contribution des différentes phases minérales présentes (oxyde de fer, phyllosilicates). Un modèle opérationnel, représentant la fraction organique comme un échangeur d'ions, a été proposé. Celui-ci permet de décrire le comportement de ces deux radioéléments sur la fraction organique de la tourbe
The environmental footprint of former uranium mining sites is a major concern for society. In order to guarantee the protection of ecosystems and thus a minimal radiological impact on the biosphere, it si important to understand and to be able to model the phenomena controlling the migration of uranium and its decay products, specially radium (226Ra) (AREVA's Envir@Mines project). In the environment, among solid phases which can retain 238U(VI) and 226Ra(II), peat is known to have relevant affinity for U(VI). Because peat is usually composed at 90 % dry weight of organic matter, the aim of this study was to qualify and quantify peat organic matter affinity for 238U(VI) and 226Ra(II). Peat samples extracted from Les Sagnes (close to a former uranium mining site in Limousin area, France) was characterized andbatch adsorption/desorption experiments were conducted. The results indicate that 226Ra(II) adsorption onto that peat is higher than 97 % for pH>4-6 (depending on the organic/mineral ratio in dry peat) corresponding to Kd values about 4500 for 500mL/g and 238U(VI) adsorption is higher than 80 % at pH>3 with Kd maximal values reaching 11000 mL/g around pH 4.5 . Only a little desorption was measured after one month.An ion exchange modelling for radium adsorption onto one type of organic matter sorption site was enough to fit the experimental adsorption Kd for the peat over the whole range of Ph . However, uranium sorption on peat can be modelled on that organic sorption site only for pH 5 to 10. From Ph 5 to 10, to explain the experimental uranium adsorption Kd values (close to 1500 mL/g), uranium sorption onto mineral phases (such as smectite and iron oxide in this study) has to be considered. An operational data set is given for both 238U(VI) and 226RA(II) sorption onto Les Sagnes peat. Unlike usual peat, peat from Les Sagnes contains more than 10 % dry weight of mineral matter. That is why it is necessary to modele sorption of those two radioelements onto mineral phases (such as smectite and iron oxide, in this study), to discriminate which part of the sorption is due to mineral phases and which one id from organic matter. An operational dataset for 238U(VI) and 226Ra(II) sorption onto Les Sagnes organic matter was determined

In experiment I), dry matter disappearance (DMD) and nitrogen disappearance (ND) of raw soybeans (RAW), solvent extracted soybean meal (SBM), heat treated whole soybeans (HT), mechanically extracted soybean meal (MEX), dry extruded soybeans (DEX), and wet extruded soybeans (TEX), were studied in situ for times of 3, 6, 12 and 24 h of rumen exposure. Five gram, air dry, samples were suspended in the rumen of a lactating Holstein cow fed a total mixed ration twice daily. The percent DMD for 24 h was as follows: RAW-85.9; SBM-56.6; HT-39.0; MEX-40.2; DEX-28.0; TEX-43.3. The greatest DMD was observed with RAW and was greater than all others (P<.01), followed by SBM which was significantly greater than all but Raw (P<.01). DEX presented the lowest DMD when compared to all other (P<.01). Percent ND values for 24 h for the soy products were: RAW-90.8; SBM-47.0; HT-32.7; MEX-23.7; DEX-16.5; TEX-23.0. The ND for RAW was significantly greater (P<.01) than all others, while the ND for SBM was similar P>.01) to HT but greater (P<.01) than MEX, DEX and TEX. ND for HT, MEX, DEX and TEX were similar (P>.01). Significant differences were observed in DMD and ND of various soybean products. As expected a high degree of degradation and ND was observed with raw soybeans. The application of heat decreased DMD and ND in SBM and application of greater heat (HT, MEX and DEX) and application of heat with moisture (TEX) resulted in products with lower DMD and lower ND. In experiment II) wheat straw acid detergent fiber (ADF) was subjected to in situ DMD and ND studies. Effects of time (612-24 h) and sample weight (1-2-3 grams) were evaluated. A lactating Holstein cow being fed a mixed ration was used. ADF dry matter (DM) weights (after incubation) expressed as a % of the original sample, were as follows: one gram: 101, 110 and 136; two grams: 99, 106 and 110; and three grams: 97, 110 and 114 for 6, 12 and 24 h respectively. The ADF DM weights of the one and two gram samples were significantly higher (P<.05) for 12 and 24 h than 6 h. When sample sizes were combined for each time, comparisons found 24 h to be significantly higher (P<.01) than 6 h. The DM changes were also reflected and magnified in the % N changes in the ADF residues. The amount of N of the one gram ADF samples increased 32% after 6 h, 122% after 12 h and 287% after 24 h (24>12>6-P<.01), and for two grams 29%-6 h, 97%-12 h and 117%-24 h (24>12>6-P<.05), and for three grams 34%-6 h, 140%-12 h and 142%-24 h (24 and 12>6-P<.01). Potential problems with DM and N contamination of ADF residue with in situ studies were demonstrated with small increases in DM weights and larger increases in N content.

In-water biogeochemical constituents and bio-optical properties of the St-Lawrence Gulf and Estuary were monitored during 5 cruises conducted between 1997-2001 accross different seasons. Measured inherent optical properties (IOPs) included vertical profiles of the absorption and attenuation coefficients and the volume scattering function as well as absorption by particles, non-algal particles, phytoplankton and coloured dissolved organic matter (CDOM). Apparent Optical parameters (AOPs) included vertical profiles of the upwelling radiance and downwelling irradiance. The spectral shape of the major IOPs like absorption by phytoplankton, CDOM and non-algal particles as well as the particulate backscattering were parameterized using conventional models and adaptations of conventional models. Descriptive statistics of each variable in the collected dataset were analysed and compared with previous findings in the literature. The optical coherence of the measurements was verified using a radiative transfer closure approach. A complete set of IOP cross-sections for optically significant biogeochemical variables were generated. The magnitude and the spatial, temporal and spectral variation exhibited by the optically significant inwater biogeochemical constituents as well as the bio-optical parameters was consistent with our current knowledge of the ecosystem. The variation of the bio-optical parameters throughout the seasons was also coherent with our expectations. All the measured and derived parameters were found to vary within the ranges reported in the literature. Evidence was presented wherein the Gulf waters, which are usually considered as case I waters could also behave like case II waters. Moreover, spectral signatures exhibited by the IOPs and AOPs were coherent with the variation detected in the concentrations of the measured (optically significant) constituents. The extracted IOP cross-sections were consistent with the results of similar studies previously performed and could eventually be used in the estimation of the biogeochemical constituent concentrations given the related component IOPs. First-order radiative transfer closure was achieved; this underscored the validity of our experimental dataset based on considerations of higher level, integrative, physics. We argue that the current data collection campaign succeeded as a comprehensive framework for describing the behavior of the St-Lawrence bio-optical provinces within the context of remote sensing objectives. This bio-optical dataset should provide the basis for the development of a rigorous, satellite-based, remote sensing algorithm for the retrieval of near surface chlorophyll, fine-tuned to the local characteristics of the St-Lawrence system.

Le livre : Principia Mathematica Philosophiae Naturalis (1687) de Isaac Newton constitue pour la science moderne un texte fondateur. Le corps de cet ouvrage est constitué de trois parties principales appelées livres. Parmi ces trois livres, les livres I et III consacrés principalement à l'étude du cosmos ont fait l'objet de nombreuses études. Le livre II consacré à l'étude de la résistance au mouvement des milieux fluides a été quelque peu délaissé et même dévalorisé par l'historiographie. Dans le livre II Newton détourne son regard du ciel et le porte sur terre. L'étude de cette partie des Principia nous permet de : revisiter et d'approfondir le concept newtonien de force, de découvrir l'usage de la notion de pression, de préciser le rôle de la géométrie euclidienne. Pour la géométrie nous avons été particulièrement attentif aux différentes fonctions des figures. Nous avons travaillé à partir de plusieurs traductions, principalement celle de la marquise du Châtelet de 1759 et de celle plus récente de Cohen et Whitman. Nos référents essentiels sont : Blay, Cohen, De Gand, Janiak, Koyré, McMullin, Smith et Westfall
Book : Isaac Newton's Principia Mathematica Philosophiae Naturalis (1687) represents a fundamental text for modern science. The body of that work is in three major parts called books. Among these three books, I and III are primarily dedicated to the study of the cosmos and have been the objects of numerous studies. Book II is dedicated to the study of resistance to movement of fluid environments and has been somewhat ignored and even devalued by historiography. In book II Newton turns away from the sky and looks down at earth. The study of that part of Principia allows us to revisit and deepen our knowledge of the newtonian concept of force, to discover and learn how to use the concept of pressure, and to clarify the role of euclidean geometry. As for geometry, we have paid special attention to the different functions of figures. We have worked with several translations, primarily Marquise du Chatelet 1759's translation, and the more recent one by Cohen and Whitman. Our essential references are Blay, Cohen, De Gand, Janiak, Koyre, McMullin, Smith and Westfall

ABSTRACT

Billions of people are living without access to safe hygienic means of personal sanitation. The sanitation gap is wide in developing countries where more people are increasingly becoming urbanised. Sanitation related diseases are some of the leading cause of mortality and morbidity among the population in developing countries especially children under age of 5 years. The responsible institutions are faced with challenge to provide suitable and affordable services to this increasing population. In Uganda, the urban poor are residing in the peri urban areas with inadequate sanitation facilities. The provision of conventional sanitation facilities are seen not be sustainable options due to contamination of both surface and underground water sources, congested housing structure and at the same time makes recycling and reuse of nutrients difficult.

This study investigated attitudes towards urine diverting toilets in one of the peri urban areas in Kampala, with the aim of finding out strategies to improve on awareness of ecological sanitation as well as popularise their use as alternative sanitation. Respondents’ views were collected through face to face interviews with 40 household respondents using a semi structured questionnaire and field observations of the household’s toilet in use as well as solid waste disposal. Four focus group discussions and 6 key informant interviews were also performed.

The respondents’ acceptance of the urine diverting toilets was relatively positive. Most of the respondents reported that the ecosan toilets are a viable option due to congested housing pattern, desire to own a toilet (for those who never had a toilet before), improved privacy, and convenience among other factors. Respondents who have no urine diverting toilets also preferred urine diverting toilets and expressed their willingness to replicate them. It was also found that residents in Kamwokya II parish prefer a double vault design to one which uses bucket. The findings also reveal that reuse of sanitized urine and faecal matter within the community is not possible since there is no space for urban agriculture. However, the respondents acknowledged a willingness to eat or buy food from a garden fertilized with sanitized urine and faecal matter. It was also found that there are no cultural and religious beliefs against reuse of sanitized urine and faecal matter. Some challenges that affected implementation of the pilot project were people’s reluctance to adopt at the beginning, delayed completion of some facilities and part time employees. Currently there is limited replication of toilets because of low cash income among the residents, delayed completion of some facilities and sceptical views by some residents.

Among the difficulties faced in use of toilet include forgetfulness by some people to spray ash after defecating, misplaced water entering the toilet vault during cleaning, children playing with the urine container etc. The provision for anal cleansing for Muslims, squat hole covers, closed urine chamber among others were suggested for system improvements. The study recommends more awareness campaigns through social marketing of toilet and reuse of nutrients, modification of design, government’s commitment and household change of behaviours are fundamental for encouraging more adoption and replication of the toilets.