This work aims to implement 3D microstructures that generate light with orbital angular momentum towards applications in Biophotonics. Over the past few decades, 3D printing has established itself as the most versatile technology with effortless adaptability. Parallel to this, the concept of miniaturiza tion has seen tremendous growth irrespective of the field and has become an estab lished trend motivated by the need for compact, portable and multi-function devices. Therefore, when these two concepts get together, i.e., 3D printing of miniaturized objects, it could lead to an exciting path with endless opportunities. When it comes to optics, miniaturized 3D printing offers the potential to create compact optical micro-systems and exhibits a way to manufacture freeform µ-optics. In particular, two-photon lithography (TPL) is a cutting edge 3D printing technology that has re cently demonstrated groundbreaking solutions for optics as it offers high resolution with a great degree of flexibility. With a TPL 3D printer, it is possible to fabricate complex µ-optical elements and employ them for compelling applications. In recent years, light with orbital angular momentum (OAM), or ”twisted” light, has captured the interests of several researchers due to its inspiring applications. Tra ditionally, to generate OAM beams, one would require bulk, table-top optics, restrict ing their applications to over-the-table setup. An alternative approach of OAM beam generation is through µ-structures over the fiber, as they can open up new opportu nities, especially in Bioscience, and facilitate in-vivo operations. In particular, this probe-like setup can be used for processes such as optical trapping, high-resolution microscopy, etc. Hence, I propose the development of a novel approach with un precedented capabilities for generating OAM beams right from single-mode optical fibers, by transforming its Gaussian-like output beam by using complex 3D printed microstructures. In this document, I will showcase designs and results on generating Bessel beams (both zeroth- and high-order) and high-NA converging beams (with and without OAM) for optical trapping from the fiber. Remarkably, I achieved the first-ever fiber-based high-order Bessel beam generation and the first-ever fiber optical tweezers with OAM.

Equal-channel angular pressing (ECAP) is one of the severe plastic deformation (SPD) to produce ultra-fine grain (UFG) material, and its principle and microstructural developments. The majority of papers on SPD materials have been devoted to the face centered cubic (FCC) structure materials such as Al, Cu and Ni. The UFG of high alloy ECAP processing has been difficult up to now, but we were successful in this study. Fe-20%Cr steel with extremely low C and N has different slip behavior from the FCC. The mechanical properties and corrosion resistance were investigated in term microstructural evolution during ECAP processing. / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University

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A method of measuring angular dependence of acoustic transmission through supercritical plates in air is discussed. The coincidence effect occurs in a supercritical plate when the component of the acoustic wave number parallel to the plate matches the bending wave number in the plate. The transmission of sound is a maximum at the angle where this trace wave number matching occurs. The theory of the coincidence effect is well-defined for unbounded thin plates using plane-wave excitation. However, experimental results for finite plates are known to diverge from theory, especially near grazing angles. An experimental setup has been developed in order to observe the coincidence effect using continuous-wave excitation and phased-array methods. Experimental results through a 0.5 mm thick aluminum bar exhibit strong maxima at the predicted coincidence angles, showing that coincidence is observable using continuous waves. Also, transmission near grazing angles is seen to diverge from infinite plate theory. Further work is suggested to improve the measurement setup and explore the source of the divergence.

The Sextant in its earliest known form consisted of divided circles and compasses with simply sights. An early Creek astronomer of the second century after Christ, Claudius Ptolemaeus, or more commonly called Ptolemy, wrote a book entitled Megale Syntaxis tes Astron- omias, also known by the Arabic title Almagest. The instrument described in this book was called the Astrolable and was used to measure the angular distance between stars. It was made of two concentric vertical circles, the largest and outer circle was about sixteen inches in diameter with graduated arc; the central ring was movable and carried the two sights.

Asphaltenic crude oil is a complex fluid containing various components with different chemical properties. When it comes in contact with water, its polar components adsorb at the oil/water interface, reducing the interfacial tension and eventually developing viscoelastic films. The interfacial films impact emulsion stability and adhere to the oil-bearing reservoirs rocks, altering their wettability and thus hindering oil mobilization. Here, we investigate the formation of crude oil/water interfacial films. We measure both the time-dependent shear and extensional interfacial rheology moduli, and we relate it to the chemical composition of the films, highlighting the role of polar aromatic molecules in film formation. Varying chemical composition of the aqueous phase, we show that the properties of the interfacial films depend not only on the concentration of ionic species in water but also on their chemical nature. In particular, we highlight the role of sulfate salt in promoting interfacial viscoelasticity and in altering the composition of fully developed films. To study the rock/fluid interaction, we fabricate mixed-wet capillaries with angular cross-sections inspired by the naturally occurring primary drainage of pore-filling brine by invading crude oil. After employing our novel coating procedure, we experimentally investigate water invasion in mixed-wet capillaries and compare it with predictions of dynamic and quasi-static (Mayer-Stowe-Princen (MSP)) meniscus-invasion models. None of the dynamic models built for uniformly-wet pores can fully describe our experimental data in mixed-wet capillaries. However, the experimental results agree with predictions of MSP theory. To our knowledge, this is the first direct experimental validation of MSP theory under mixed-wet conditions. We confirm the possibility of spontaneous piston-type imbibition with high ($> 90^{\circ}$) advancing contact angles into mixed-wet pores, given that the contact angle is lowered below a critical value that is a function of pore geometry and residual water saturation. In oil reservoirs, injection of specific brines would be required to change the contact angle to values below the imbibition threshold. Finally, we extend our study and introduce a powerful 3D high-speed laser imaging of dynamic fluid flow in angular capillaries and investigate its capability to capture non-equilibrium shapes of fluid interfaces.

<p> A high speed recoil transport system is developed making possible the simultaneous study of many decay products of the compound nucleus 221*Ac. Oeterminati ons of the efficiency properties of the transport system, essential for absolute cross section measurements , are discussed in detail. </p> <p> A study of angular momentum effects is made possibly by synthesis of 221*Ac using three heavy ion reactions. Absolute cross sections for (HI,xn) and (HI,pxn) reaction products are determined relative to established cross sections for production of 150Dy. Relative cross sections for francium production are also determined. </p> <p> A sophisticated statistical model calculation is adapted to provide a framework for interpretation of the results. Some insight is gained into the roles played by basic physical concepts in the systematic of compound nucleus decay in this mass region </p> / Thesis / Doctor of Philosophy (PhD)

<p> The motion of energetic charged particles inside a crystalline solid is strongly dependent upon the orientation of the ion beam and target. This effect is commonly known as the "channeling" effect. In this report, the development of a computer code is presented which simulates the 3-D ion scatterings experienced by energetic particles moving in a crystalline solid. A Monte Carlo technique is incorporated in the code to calculate scattering angles, range distribution, backscattering distribution and angular distribution of incident ions. The Thomas-Fermi interatomic potential is used for binary collision process and the continuum potential is used for the potentials experienced by the channeled ions inside crystal lattices. </p> / Thesis / Master of Engineering (MEngr)

In absence of external fields, vibrational modes of periodic systems are usually considered as linearly polarized and, as such, they do not carry angular momentum. Our work proves that non-adiabatic effects due to the electron-phonon coupling are time-reversal symmetry breaking interactions for the vibrational field in systems with non-collinear magnetism and large spin-orbit coupling. Since in these systems the deformation potential matrix elements are necessarily complex, a nonzero synthetic gauge field (Berry curvature) arises in the dynamic equations of the ionic motion. As a result, phonon modes are elliptically polarized in the non-adiabatic framework and intrinsic vibrational angular momenta occur even for non-degenerate modes and without external probes. These results are validated by performing fully relativistic ab-initio calculations on two insulating platinum clusters and a metallic manganese compound, with non-collinear magnetism. In both cases, non-adiabatic vibrational modes carry sizeable angular momenta comparable to the orbital electronic ones in itinerant ferromagnets.

Långa laddningstider eller bristfällig prestanda kan ha en negativ effekt på användarupplevelsen av en webbsida. Utvecklare kan ta hänsyn till detta vid skapande av ett system genom valet av ramverk, men eftersom det finns ett brett utbud av JavaScript ramverk, som är ett av de mest populära programmeringsspråken, kan det bli en utmaning. Syftet med arbetet är att med hjälp av olika tester och testermetoder jämföra prestandan mellan JavaScript ramverken Angular, React och Vue för att hjälpa utvecklare att välja ramverk. Testerna som ramverken genomförde var rendering av bilder och videor samt skapande, uppdaterande och borttagande av 1 000/50 000 DOM element i webbläsarna Google Chrome, Microsoft Edge och Mozilla Firefox för att samla in kvantitativa data. Verktyget WebPageTest användes för att mäta prestandan vid rendering av bilder och videor. Tidsstämplarna performance.now() och Date.now() användes för att mäta tiden det tog att utföra DOM manipulationer i millisekunder.   Resultatet för ramverken lades in i tabeller och en poängskala skapades för att räkna ut vilket ramverk som var mest effektivt. React presterade bäst vid rendering av bilder och videor med 53 poäng, Vue resulterade i 37 poäng och Angular 5 poäng. Vid DOM manipulering var Vue mest effektiv och tilldelades 42 poäng, Angular fick 32 poäng och React 14 poäng. För att ta reda på vilket av ramverken som generellt var effektivast summerades poängen för båda testerna och resulterade i att Vue totalt presterade bäst med 79 poäng, React hamnade på andra plats med 67 poäng och Angular sist med 37 poäng. React och Vue hade små marginaler mellan varandra i resultatet vid rendering av bilder och videor vilket gör till ett passande ramverk för webbsidor som kräver regelbunden DOM manipulering och som innefattar bilder och videor. Angular presterade bäst vid skapande och uppdatering av 50 000 element i alla webbläsare samt uppdatering av 1 000 element i Google Chrome och Mozilla Firefox. React var minst effektiv vid skapande och uppdatering av element, men presterade bäst vid borttagning av 50 000 element i Google Chrome och Microsoft Edge.