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Synthetic Studies of Amide-functionalized Helicene-like Molecules / アミド基を持つヘリセン様分子の合成研究Xing, Yongning 24 May 2021 (has links)
京都大学 / 新制・課程博士 / 博士(薬科学) / 甲第23386号 / 薬科博第143号 / 新制||薬科||16(附属図書館) / 京都大学大学院薬学研究科薬科学専攻 / (主査)教授 川端 猛夫, 教授 高須 清誠, 教授 大野 浩章 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM
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Helical Poly(quinoxaline-2, 3-diyl)s Bearing Boronyl Pendants as a Platform of New Chiral Catalysts and Ligands / ボロン酸置換らせん状ポリキノキサリンをプラットフォームとした新規キラル触媒および配位子の開発Murakami, Ryo 23 May 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21275号 / 工博第4503号 / 新制||工||1700(附属図書館) / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 杉野目 道紀, 教授 村上 正浩, 教授 松原 誠二郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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Helical transition metal complexes as catalysts for asymmetric sulfoxidations and aldol addition reactionsBarman, Sanmitra January 1900 (has links)
Doctor of Philosophy / Department of Chemistry / Christopher J. Levy / Stepped helical salen complexes with vanadium as the central metal were synthesized and characterized. The helicity in these complexes arise from the fused phenyl rings (phenanthryl and benz[a]anthryl) as sidearms, whereas the chirality arises from the chiral cyclohexyl diamine or binaphthyl diamine backbones. These complexes showed good yields and moderate enantioselectivity in asymmetric sulfoxidation reactions with methylphenyl sulfide as the substrate and H2O2 or cumene hydroperoxide as the oxidants. To further improve the closed nature of these complexes with a tetradentate salen ligand, we synthesized and characterized vanadium complexes with tridentate (S)-NOBIN backbone Schiff base ligands with phenanthryl and benz[a]anthryl as the sidearms. After initial catalytic study, we concluded that these catalysts are too open in nature to impose face selection during asymmetric induction. We also synthesized and characterized vanadium and titanium salan complexes. These complexes can adopt β-cis geometry, thereby making the complex “chiral at metal” and they are known for better catalysts in terms of asymmetric induction than their unreduced counterparts. However, these complexes showed better catalytic activity than their unreduced counterparts in sulfoxidation reactions with methylphenyl sulfide as the substrate and H2O2 or cumene hydroperoxide as the oxidants. We also put an effort to synthesize mixed salen complexes with vanadium as the central metal. These complexes have two different sidearms attached to one backbone unit. However, our method did not work well to produce pure mixed salen ligands. The catalysis results for mixed salen vanadium complexes are also comparable to the unreduced vanadyl salen complexes. Lastly, we synthesized and characterized new helical titanium Schiff base complexes with (S)-NOBIN backbone and phenanthryl and benz[a]anthryl sidearms. Single crystal studies showed that these complexes exist in the M helical conformation in the solid state. These complexes showed moderate activity in asymmetric aldol addition reactions between 2-methoxy propene and different aldehydes.
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Mekaniska beräkningar av armeringstråd vid förläggning på högspänningskablar / Mechanical calculations of reinforcing wire upon the application on high voltage cablesNilsson, Philip January 2014 (has links)
This thesis has taken place at ABB High Voltage Cables in Karlskrona and focuses on their reinforcement process (AR50) which reinforces the cable by application of reinforcement wires. The research is strictly limited to only the short period during the application of the wire on the cable and investigates stress differences in one reinforcing wire depending on cable - and wire dimensions as well as brake forces used in the production. The study follows a model - and theory development research process combined with a testing process to obtain the results. The study aims is to increase and expand ABB's knowledge about the reinforcing process that is used to strengthen and protect ABB’s all different high voltage cables together with a computational calculation model. The model is developed in the FEA (Finite Element Analysis) program ABAQUS through a dynamic explicit model. An explanation of how the calculation model has been built and the parameters used are described in this report. These parts then contribute to the outcome of the study which provides a sense that the brake force used in AR50’s reinforcement process does not need to be controlled with a high precision so long as it is large enough to hold the reinforcement wire stretched upon the application. The study also shows that different cable - and wire dimensions does not affect the stress levels somewhat significantly by reinforcing the process and that the nipple used in reinforcement process to press down the reinforcing wire on the cable is the main source that determines how the stress distribution looks like on the reinforcement wire. / Detta examensarbete har tagit plats på ABB High Voltage Cables i Karlskrona och fokuserar på deras armeringsprocess (AR50) som förstärker kabeln genom påläggning av armeringstrådar. Arbetet är starkt begränsat till enbart den korta perioden för själva påläggningen av tråden och undersöker spänningsskillnader i en armeringstråd beroende på olika kabel – och tråddimensioner samt bromskrafter som används i produktionen. Studien följer en modell – och teoriutvecklande forskningsprocess kombinerat med ett utprövande resultatbildande. Studiens syfte är att tillsammans med en beräkningsmodell öka och fördjupa ABBs kunskaper kring armeringstråden som idag används för att stärka och skydda ABBs alla olika högspänningskablar. Beräkningsmodellen tas fram i FEA (Finita Element Analys) prorammet ABAQUS genom en dynamisk explicit modell. En förklaring till hur beräkningsmodellen har byggts upp och vilka parametrar som används beskrivs i rapporten. Dessa delar bidrar sedan till resultatet i studien som ger en bild av att bromskraften som används i AR50s armeringsprocessen inte behöver kontrolleras med en hög precision så länge den är tillräckligt stor för att hålla armeringstråden sträckt vid påläggningen. Studien visar också att olika kabel – och tråddimensioner inte påverkar spänningsnivåerna något markant vid armeringsprocessen och att nippeln som används i armeringsprocesen för att trycka ner armeringstråden mot kabeln bestämmer hur spänningsbilden ser ut. / <p>This thesis is kept confidential</p>
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HIGH RATE DIGITAL CASSETTE RECORDERSBanks, Simon 11 1900 (has links)
International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Recorders conforming to IRIG Standards have served the data recording community well for many years. Initially, most systems were analog in nature, recording data in either direct or FM modes but as the need for digital recording developed, the IRIG recorder was successfully adapted for this purpose by the addition of formatting and coding sub-systems to form the High Density Digital Recorder (HDDR). Today, user requirements for higher speed, higher capacity and more convenient systems have presented equipment designers with new challenges in terms of the correct choice of technology and system architecture.
It is not surprising that system designers should turn for inspiration first to the very high speed transverse and helical products which had been developed for the broadcast industry since these technologies possess many of the attributes necessary for a high rate digital data recorder. It is unfortunate that it has now become a truism that the only logical progression from the longitudinal IRIG system is by means of rotary technology.
Recent developments in a technology known as micro-track recording now call this assumption into question. Recording systems based on micro-track technology are available and others are in an advanced state of development, and these offer a costeffective, attractive and low risk alternative to rotary systems for both high rate data capture and tape mass storage applications.
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Visualization and Quantification of Helical Flow in the Aorta using 4D Flow MRIGustafsson, Filippa January 2016 (has links)
Due to the complex anatomy of the heart, heart valves and aorta, blood flow in the aorta is known to be complex and can exhibit a swirling, or helical, flow pattern. The purpose of this thesis is to implement methods to quantify and visualize both the speed of helicity, referred to as the helicity density, and the direction of helicity, which is measured by the localized normalized helicity. Furthermore, the relationship between helicity and geometrical aorta parameters were studied in young and old healthy volunteers. Helicity and geometrical parameters were quantified for 22 healthy volunteers (12 old, 10 young) that were examined using 4D Flow MRI. The relation between helicity and the geometry of the aorta was explored, and the results showed that the tortuosity and the diameter of the aorta are related to the helicity, but the jet angle and flow displacement do not appear to play an important role. This suggests that in healthy volunteers the helical flow is primarily affected by the geometry of the aorta, although further trials should be performed to fully characterize the effects of aortic geometry. The results also show that the helicity changes with age between the two age groups and some of the geometrical parameters also has a significant difference between the age groups.
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Study of Hot Extrusion of Hollow Helical TubesChang, Cheng-nan 27 August 2012 (has links)
This study investigates analytically and experimentally extrusion processes of magnesium hollow tubes by a single-cylinder extrusion machine and double-cylinder extrusion machine. The first part of this study is to conduct analysis and experiment of hollow helical tube extrusion by single-cylinder extrusion machine. Firstly, a design criterion is proposed to determine the forming parameters and discuss the effects of product size, extrusion ratio, billet length, etc. on the mandrel surface stress. The effects of the die bearing part length, angle of rotation, extrusion speed, initial temperature, petal number, etc. on the radial filling ratio are also investigated. Better parameters are chosen from analytical results to conduct hot extrusion experiments for obtaining sound products. Microstructure observation and hardness test are conducted at the cross-section of the product. The experimental values of extrusion load and product¡¦s dimensions are compared with the analytical values to verify the validity of the analytical models. The second part of this study is to conduct analysis and experiment of hollow tubes extrusion by a double-cylinder extrusion machine. The effects of extrusion ratio, billet length, mandrel diameter, etc. on the drawing force on the mandrel and critical conditions without mandrel fracture are discussed.
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Heat Transfer of a Multiple Helical Coil Heat Exchanger Using a Microencapsulated Phase Change Material SlurryGaskill, Travis 2011 December 1900 (has links)
The present study has focused on the use of coil heat exchangers (CHEs) with microencapsulated phase change material (MPCM) slurries to understand if CHEs can yield greater rates of heat transfer. An experimental study was conducted using a counterflow CHE consisting of 3 helical coils. Two separate tests were conducted, one where water was used as heat transfer fluid (HTF) on the coil and shell sides, respectively; while the second one made use of MPCM slurry and water on the coil and shell sides, respectively. The NTU-effectiveness relationship of the CHE when MPCM fluid is used approaches that of a heat exchanger with a heat capacity ratio of zero. The heat transfer results have shown that when using a MPCM slurry, an increase in heat transfer rate can be obtained when compared to heat transfer results obtained using straight heat transfer sections. It has been concluded that the increased specific heat of the slurry as well as the fluid dynamics in helical coil pipes are the main contributors to the increased heat transfer.
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Marine invertebrate sperm: Assessment of sperm quality using computer-aided sperm analysisBennett, Monique January 2020 (has links)
Philosophiae Doctor - PhD / 2022-04-30
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The Physical and Mechanical Aspects of Orthodontic AppliancesBibby, R.E January 1978 (has links)
Magister Scientiae Dentium - MSc(Dent) / These laws were first published in Latin,in 1687.The first law may be literally translated thus, Every body continues in its state of reat or of uniform motion in a straight line ,unless it is compelled to change that state by impressed force. This meano that if a body is at rest it will remain so unless some force acts on it,if in motion ,the velocity of motion must continue uniform unless some force acts to increase it or diminish it. Also the direction of motioA mast continue unchanged and therefom rectilinear unless some force causes it to be diverted.
This law therefore supplies us with a definition of force; Force is that which produces or tends to produce, motion 0.' change of motion.
Newton's second law of motion may be translated as follows:- Newton's second law of motion may be translated as follows:- The change of motion (produced)is proportional to the impressed force producing it,and pursues the direction in which that force is impressed. This law leads to a method of measuring forces. If we change the velocity with which a mass is moving,we also change its momentum. Change in momentum will serve to measure force.lt seems obvious that whatever change in momentum is produced by a force, twice the force will produce twice the change ,etc.i.e. the change is directly proportional to the force. For a given mass,m,change of momentum ,mv,means change of velocity;the change of velocity per unit time is aceeleration,a;the change in momentum per unit time is therefore malf we employ absolute units (poundals or dynes)this can be shown as; Newton's third law of motion states that 'to every action there is an equaI and opposite reaction'.This law recognises the dual aspect of forces It a tooth is pushed by a finger spring ,the spring is also pushed by the tooth,and an eqpal counter force acts towards the spring unti1 the biology of the system intervenes. This dual stress is called pressure.
Retracting incisors against posterior segments it is apparent that the reaction of the posterior segments must be equal and opposite to the incisors.In this case the two forces act away trom each other,and tG this dual stress we give the name tension.
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