Дисертації з теми "Additional layers"

Bragg waveguide with additional layers between hollow core and periodic cladding is considered. On the base of dispersion equation solutions dispersion diagrams are obtained. The transversal spatial distributions of the electric field intensity are shown. The characteristics of Bragg waveguide respect to additional layer thickness and permittivity are considered. It is shown that increase of additional layers thickness results in increase of slow-waves number. Also field intensity decay in channel is reduced. Number of slow-waves increases respect to additional layers permittivity too. But distribution of the electric field intensity in the channel changes insignificantly. So one can tune additional layers parameters to get expected Bragg waveguide characteristics.

Modified scheme of Bragg reflection waveguide with additional layers between the hollow core and cladding is considered. Dispersion diagrams are calculated on the base of dispersion equations solutions for ordinary and modified Bragg waveguides. Slow-wave regimes are considered for both kinds of structure. Electric field spatial distributions for localized slowwave modes of Bragg reflection waveguide are obtained. It is shown that modified scheme of Bragg waveguide provides the enhanced localization of the surface modes field in the hollow core. Therefore modified Bragg waveguide is the promising electrodynamic system not only for laser-driven accelerators but also for the vacuum electron devices where usual slow-wave structures are unconvenient.

Pneumatic clear foil cushion systems, notably as ETFE foil cushions have been developed as an alternative technology to large-scale glass glazing systems for wide-span buildings. The systems display better thermal performance and have advantages of extremely low dead-weight constructions compared to conventional glazing systems, and thereby the increasing popularity of foil cushion cladding systems have been witnessed in the last decades. However due to their lightweight and thinness, the thermal behaviour of architectural foil membranes exhibits a high responsiveness to variations in external conditions. For this reason, it is argued that the reliable prediction of the thermal environment experienced in a space enclosed by a tensile membrane skin construction would require a bespoke modelling of the dynamic thermal behaviour of such a construction at first. Building envelopes clad with such cushions, such as the famous Eden project in the UK, need a dynamic system to control overheating in summer. A cooling liquid layer constructed within a clear multi-layer toil cushion envelope is proposed in this thesis. It enables rapid cooling effects on the building envelope. The system is based on an evaporative cooling mechanism and is integrated with the inflated cushion to provide desired cooling effect eco-friendly. The implications of the forms and configurations of clear foil cushion constructions with and without a cooling liquid layer in the overheating control were evaluated in this research project. Data were collected from a series of experiments to ascertain the effects of the additional cooling water layer on heat transfer processes within the foil skin construction. The results demonstrated that the thermal behaviour of a foil penal depended mainly on surface convection and radiation heat transfer and the cooling performance of the water layer within the foil skin constructions was evident. The initial experimental outcomes were valuable for the design of such novel dynamic cooling systems. In order to assess the effect that different pneumatic foil skin constructions with a water layer might have on thermal conditions inside the enclosed space, the thermal behaviour of full-scale indoor double-layer foil cushion enclosure and triple-layer foil skin construction, with varying evaporative cooling integrative ways and foil skin constructions, were tested during the course of this research. The test datasets were compared according to the research objectives and with the environmental control strategy proposed at the initial design stages. The investigated thermal behaviour of the foil skin constructions incorporating a water layer serves as a reference basis for the analytic modelling of the tested double and triple-layer foil skin constructions in order to predict their surface temperatures and the solar radiation directed into the space they enclose. The approach is based on a detailed modelling of the radiative and convective heat transfer processes affecting the membrane surfaces. These prediction results derived from the model were compared against the environmental data obtained on the test rigs. The developed analytical model is only tentative, as some thermal transfer processes, such as long wave radiation exchanges between the foil sheets, have not been accounted for in this model. Further work is required to develop this model in order to appreciate the thermal performance of such novel foil cushion constructions more precisely and extend their building applications.

The Stanton gauge technique provides an indirect method for measurement of skin friction on a smooth aerodynamic surface in which a pressure tap is available. This thesis presents the design and evaluation of a new type of skin friction measurement gauge based on the Stanton gauge concept but not requiring a surface pressure tap. This new skin friction measurement gauge, called a "Flow Tab", can therefore be used on an aerodynamic model or aircraft surface without alteration of the surface. The Flow Tab is thus particularly well-suited to use with Cal Poly's Boundary Layer Data System (BLDS), a small, self-contained instrument that can be installed onto a model or aircraft surface without permanent alteration of the surface. A series of preliminary experiments conducted in a low-speed wind tunnel on a flat plate model with mild favorable pressure gradient, with both laminar and turbulent boundary layers, led to selection of three variants of the Flow Tab design. These Flow Tabs had edge heights of 0.002, 0.0035, and 0.005 inches, giving dimensionless heights h+ of 1.4 -16 over the streamwise Reynolds number range of about 0.7 to 2.2 million. Uncertainty analysis and test results demonstrated that better than 10% measurement uncertainty for the Flow Tab results could be achieved with edge heights of 0.0035 and 0.005 inches using the same calibration equations as published for the Stanton gauge. Further investigation of its performance over a wider range of Reynolds numbers, and in more complex conditions including those encountered on swept wings with a variety of pressure gradients, is recommended. Integration of the flow tab with BLDS for flight testing applications presents challenges related to its relatively small pressure signal that may require some special modifications to existing BLDS hardware and software.

Дисертація на здобуття вченого ступеня кандидата технічних наук за спеціальністю 05.15.02 – «Підземна розробка родовищ корисних копалин». ДВНЗ “Національний гірничий університет”, Дніпропетровськ, 2011.
Диссертация на соискание учёной степени кандидата технических наук по специальности 05.15.02 - "Подземная разработка месторождений полезных ископаемых". ГВУЗ "Национальный горный университет", Днепропетровск, 2011.
The dissertation on reception of the scientific degree of candidate technical science on a specialty 05.15.02 – «Underground mining of mineral deposits». SHEI “National Mining University”, Dnipropetrovsk, 2011.
Дисертація присвячена обґрунтуванню технологічних параметрів підземної розробки тонких і некондиційних вугільних пластів із присічкою слабометаморфізованих вміщуючих порід, а також установленню діапазону ефективності виїмки за умови запропонованих рішень з підвищення якості гірської маси з урахуванням використання вторинної сировини. Розроблено алгоритм обґрунтування раціональних параметрів технологічних схем виїмки тонких і некондиційних вугільних пластів у складних гірничо-геологічних умовах шахт Західного Донбасу. В дисертації запропоновано залучення додаткового видобутку гірської маси, що виймається з некондиційних вугільних пластів з підвищенням якості при готуванні композиційного палива з використанням відходів гірничого виробництва за допомогою адгезійно-хімічної технології згрудкування. На основі отриманих результатів обґрунтовано технологічні параметри отриманого твердого палива відповідним вимогам при спалюванні, а також можливість використання відходів гірничого виробництва як додатковий видобуток при підземній розробці. Очікуваний річний економічний ефект від впровадження рекомендацій при видобутку на шахті «Дніпровська» ВАТ «Павлоградвугілля» сягає 21,715 млн.грн. Результати запропоновані і впроваджені в технологічні проекти при одержанні додаткового видобутку на вугільних підприємствах Дніпропетровської, Донецької і Луганської областей.
Диссертация посвящена обоснованию технологических параметров подземной разработки тонких и некондиционных угольных пластов с присечкой слабометаморфизированных вмещаючих пород, а также установлению диапазона эффективности выемки при условии предложенных решений по повышению качества горной массы с учетом использования вторичного сырья. В роботе выполнено исследование качества добываемого угля с учётом изменения горно-геологических условий в выемочном столбе. Проведён анализ изменения качественных характеристик добываемой горной массы, по технологической цепочке от очистного забоя на поверхность. Разработан алгоритм обоснования рациональных параметров технологических схем выемки тонких и некондиционных угольных пластов в сложных горно-геологических условиях шахт Западного Донбасса. В диссертации предложено и обосновано привлечение дополнительной добычи горной массы, которая вынимается из некондиционных угольных пластов с повышением качества при приготовлении композиционного топлива с использованием отходов горного производства с помощью адгезионо-химической технологии окускования. Выполнен комплекс исследований гранулометрического, минерального и химического составов добываемой горной массы, угольных штыбов и шламов. При аналитической обработке результатов исследований гранулометрического состава установлено требование к подготовке композиционного топлива к процессу окускования, при котором все пробы, имеющие классы крупности более 5-6 мм, должны быть далее измельчены с помощью механических средств. При изучении минерального и химического состава были получены подробные данные, с помощью которых можно определить виды активирующих или добавляющих адгезионные (клеящие) свойства веществ, а также дать точный прогноз параметров процесса окускования твёрдого топлива. В результате исследований электрокинетических свойств составляющих композиционное топлива экспериментально установлено, что при активации и перетирании показатели заряженности на поверхности частиц увеличиваются в среднем 2-2,5 раза. При этом рост заряженности ведёт к увеличению прочности и улучшению структурообразования топлива. Учёт этих закономерностей позволяет обосновать физико-механические параметры композиционного топлива с крепостью на одноосное сжатие более 90 кг/см2. На основе полученных результатов исследований обоснованы технологические параметры полученного твердого топлива соответствующие требованиям при сжигании, а также возможность использования отходов горного производства как дополнительной добычи при подземной разработке. Ожидаемый годовой экономический эффект от внедрения рекомендаций при добыче на шахте "Днепровская" ОАО "Павлоградуголь" достигает 21,715 млн.грн. Результаты предложены и внедрены в технологические проекты при получении дополнительной добычи на угольных предприятиях Днепропетровской, Донецкой и Луганской областей.
The dissertation is devoted to the substantiation of the technological parameters of underground mining shallow and sub-standard coal layers of weakly metamorphosed adjoining rocks, as well as to determining of the range of the effectiveness of mining in the condition of suggested by decision on the increase of the quality of rock with allowance for using of secondary raw material. The algorithm of the substantiation of the rational parameters of the technological schemes of mining shallow and sub-standard coal layers in complex geological mining conditions on mines of West Donets Basin is developed.

Åhaga is a facility building for music, theater, sports, trade shows, product-launches and other events located in the city of Borås. The building is owned and run by the Åhaga Foundation and annually has over 100 000 people visiting it for different purpose. It consists of the original part from 1903 and three different extensions from 1920, 1940 and 2002.   The task of this project was to do another extension to the existing building which deals with the question of adjusting and relating to Åhga's cultural/ historical context and together with the original building meet new demands and functions.    "The accumulation of overlapping traces from successive periods, each trace modifying and being modified by the new additions to produce something like a collage of time” is a thought shared by Kevin Lynch in his work What time is this place.    The essence of the project has been to add a new layer of time to a historical context while enhancing the complexity and contrast. The aim has been to accomplish an interesting architectural entirety.
Åhaga är en anläggning för musik, teater, sport, mässor, produktlanseringar och andra evenemang som ligger i Borås. Byggnaden ägs och förvaltas av Åhaga Stiftelse och årligen har över 100 000 besökare för olika ändamål. Anläggningen består av den ursprungliga delen från 1903 och tre olika tillbyggnader från 1920, 1940 och 2002.    Uppgiften för det här projektet var att göra ett ytterligare tillägg till den befintliga anläggningen och som tar upp frågan om hur nya tillägg tar hänsyn till det kulturhistoriska värdet av en befintlig byggnad och tillsammans med den ursprungliga byggnaden uppfyller nya krav och funktioner.    "The accumulation of overlapping traces from successive periods, each trace modifying and being modified by the new additions to produce something like a collage of time” är vad Kevin Lynch skriver i hans bok What time is this place.    Kärnan i projektet har varit att lämna spår från vår tid i ett historiskt kontext och samtidigt stärka komplexitet och kontrasten. Målsättningen i projektet har varit att åstadkomma en intressant arkitektonisk helhet.

L'étude du rôle du fer et du manganèse lors des premiers stades d'oxydation d'alliages cuivre-nickel industriels de type 90/10 est conduite sur la base d'une confrontation entre deux nuances dont l'une est chargée en ces éléments (1. 2% de fer et 0. 8% de manganèse). Les oxydations sont réalisées pour une gamme de températures comprises entre l'ambiante et 450° C et suivies à l'aide de méthodes d'analyse complémentaires. La spectroscopie de photoélectrons induits par un rayonnement X et la sonde atomique sont utilisées pour les oxydations à basse température (<200° C) alors que les spectroscopies optiques (IRFT et UV-Vis-PIR) et la spectrométrie de masse des ions secondaires le sont pour de plus hautes températures. La confrontation des résultats obtenus par ces diverses techniques révèle que le film d'oxydes formé, quelle que soit la température, s'organise selon une structure duplex ou bicouche avec une couche riche en oxyde de cuivre plus en surface (Cu2O puis CuO pour des oxydations plus importantes) et un mélange d'oxydes de cuivre et de nickel plus en profondeur (Cu2O et NiO). L'étude des cinétiques d'oxydation montre l'existence de deux mécanismes de diffusion contrôlant l'oxydation: diffusion du cuivre de l'alliage vers l'interface oxyde-air pour les premières étapes d'oxydation, puis diffusion de l'oxygène de la surface vers l'alliage pour des temps d'oxydations plus importants. Les éléments d'addition, Fe et Mn, sont toujours présents dans la couche interne d'oxydes. Ils modifient la cinétique de croissance ainsi que la composition et l'adhérence des films d'oxydes formés

The thesis is focused on the design and elaboration of the project documentation of the extension of the elementary school, which is located in Starý Plzenec. The documentation contains requirements according to valid regulations. The proposal is based on the investor's request, which was published as part of the architectural competition announcement. A new building with 1 underground and 3 floors, forming the Y-shaped ground plan, is located on a slightly sloping terrain. In the building there are cloakrooms, kitchen, dining room, 4 main and 4 professional classrooms and hygienic and technical background. The project proposes a slight modification of the existing building. This proposal solves the barrier-free accessibility of both buildings, except for the attic classroom of the existing building. The project also counts from the second construction phase, the construction of a sports hall on the schools premises, which is still not dealt with. In proposal is a new main entrance to the building from the southern side. The support system is wall-mounted. The perimeter walls are made of monolithic concrete connected to concrete monolithic horizontal bearing structures. The inner bearing walls are made of ceramic blocks. The building is covered with a single-layer flat roof with a vegetation layer. The thermal insulation of the building is solved by a thermal insulation system with a ventilated facade. Fire safety, energy saving and thermal protection are provided.

Дисертаційна робота присвячена визначенню закономірностей формування фазового складу, структури і магнітних властивостей в нанорозмірних плівках Fe50Pt50-Au та багатошарових композиціях [Pt/Fe]n (n = 1, 4, 8) на підкладках SiO2(100 нм)/Si(001) та Al2O3 (1010) при термічних відпалах. Встановлено, що контролюючи рівень механічних напружень та їх знак у шарі Fe50Pt50 зміненням товщини, розташування, кількості додаткових шарів Au, швидкості нагріву та атмосфери при відпалі (вакуум, азот, водень), можна керувати процесами упорядкування та формуванням фазового складу, структури та магнітними властивостями в плівкових композиціях. Застосування водневої термообробки прискорює процеси упорядкування в плівках Fe50Pt50/Au/Fe50Pt50 порівняно з відпалом у вакуумі за рахунок створення додаткових стискаючих напружень при втіленні атомів водню у пустоти кристалічної гратки фази L10-FePt. При цьому вісь легкого намагнічування c у зернах фази L10-FePt розташовується у площині плівки. Швидкий термічний відпал плівкових композицій [Pt/Fe]n (де n=4, 8) на підкладках SiO2(100 нм)/Si(001) в атмосфері азоту призводить до орієнтованого росту зерен фази L10-FePt з віссю легкого намагнічування c, розташованою в напрямку [001], перпендикулярному площині плівки.
The work is devoted to definition of the phase composition formation regularities, structure and magnetic properties in nanoscale Fe50Pt50-Au films and multilayered [Pt/Fe]n (n = 1, 4, 8) compositions on SiO2(100 nm)/Si(001) and Al2O3 (1010) substrates at thermal annealings. It is established that by supervising of mechanical stresses level and their sign in Fe50Pt50 layer by change of a thickness, location, quantity of additional Au layers and annealing conditions (temperature, duration, speed of heating and atmosphere  vacuum, nitrogen, hydrogen) one can operate by ordering processes and phase compound formation, structure and magnetic properties of film compositions The variations in residual stresses/strains level and sign in the FePt layer of as-deposited films influense the change in the ordered L10-FePt phase formation temperature, structure and the coercivity in the film compositions. Increasing the level of compressive stresses in the Fe50Pt50 layer causes a decrease in the ordering temperature and improvement of the magnetic properties. It is established that oriented grain growth with c-axis of easy magnetization in the [001] direction perpendicular to the film plane at annealing in vacuum occurs in films with a smaller thickness of the intermediate Au(7.5 nm) layer due to the higher level of compressive strains in the deposited films. Increasing the thickness of the Au layer to 15 nm and reducing the level of compressive deformations contributes to the growth of FePt grains with the c-axis of easy magnetization in the plane of the film. The same orientation can be achieved by increasing the thickness of the intermediate Au layer to 30 nm. 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Thus the c-axis of easy magnetization in L10-FePt phasephasephase phase grains is located in the film plane. Hydrogen treatment allows to obtain higher values of coercivity (27.3 kOe) in Fe50Pt50/Au/Fe50Pt50 film compositions at a lower annealing temperature of 700 °C than at annealing in vacuum (900 °C), due to the intensive penetration of hydrogen atoms into the film. It was determined that due to the action of the compressive stress during the diffusion of gold along the grain boundaries and the increase in the number of interfaces in films with an intermediate Au(7.5 nm) layer, the ordered L10-FePt phase formation temperature the can be reduced compared to the other Au layer location. In the films with various Au layer location (top, intermediate, under-) separated from the substrate, the same tendency of the A1→ L10 phase transformation temperature changing as in the films on the substrate is remained: the ordering temperature is lower in film with intermediate Au(7.5 nm) layer then in Au/FeAu/FeAu/FeAu/Fe 50 Pt 50 and and and and Fe 50 Pt 50 /Au filmsfilmsfilmsfilmsfilms. In this work it is also shown that the increase in the number of interfaces in [Pt/Fe]n film compositions, where n = 1, 4, 8, while maintaining the total film thickness, promotes the activation in diffusion processes and the formation of the disordered phase A1-FePt in the composition [Pt/Fe]4 and partially ordered regions with tetragonal distortions in the [Pt/Fe]8 composition already during deposition. Rapid thermal annealing of [Pt/Fe]n film compositions (where n = 4, 8) on SiO2(100 nm)/Si(001) substrates in nitrogen atmosphere leads to the oriented growth of L10-FePt phase grains with a c-axis of easy magnetization, located in [001] direction, perpendicular to film plane. The recommendations for controlling the stress state, the reduction of the temperature of the ordered L10-FePt phase formation, the obtaining of c-axis of easy magnetization oriented perpendicular or parallel to the film plane in the film based on FePt, application of which by thermal activated method will allow to increase the magnetic recording density and storage information were developed
Диссертационная работа посвящена определению закономерностей формирования фазового состава, структуры и магнитных свойств в наноразмерных пленках Fe50Pt50-Au и многослойных композициях [Pt/Fe]n (n = 1, 4, 8) на подложках SiO2(100 нм)/Si(001) и Al2O3 при термических отжигах. Установлено, что контролируя уровень механических напряжений и их знак в слое Fe50Pt50 изменением толщины, расположения, количества дополнительных слоев Au, скорости нагрева и атмосферы при отжиге можно управлять процесами упорядочения и формированием фазового состава, структуры и магнитными свойствами в пленочных композициях. Применение водородной термообработки ускоряет процессы упорядочения в пленках Fe50Pt50/Au/Fe50Pt50, по сравнению с отжигом в вакууме, за счет создания дополнительных сжимающих напряжений при внедрении атомов водовода в пустоты кристаллической решетки фазы L10-FePt. При этом ось легкого намагничиваня c в зернах фази L10-FePt располагается в плоскости пленки. Быстрый термический отжиг пленочных композиций [Pt/Fe]n (где n=4, 8) на подложках SiO2(100 нм)/Si(001) в атмосфере азота приводит к ориентированному росту зерен фазы L10-FePt с осью легкого намагничивания c, расположенной в направлении [001], перпендикулярном плоскости пленки.

Les effets d'amelioration des capacites de passivation apportees par le molybdene et les effets de depassivation induits par le soufre adsorbe et en solution solide ont ete etudies en milieu h::(2)so::(4) sur des alliages monocristallins a base de nickel contenant 2% et 6% de molybdene, a l'aide de techniques electrochimiques et radiochimiques (traceur s**(35))

Le diamant est un semi-conducteur tres prometteur pour les applications electroniques a haute temperature et de forte puissance. Neanmoins, pour optimiser les performances des dispositifs electroniques actuels, il est indispensable de mieux connaitre et de minimiser la concentration des defauts residuels qui limitent l'efficacite du dopage. Pour cela, nous avons elabore des couches minces de diamant dopees au bore, et etudie l'influence de l'incorporation de bore sur les proprietes du diamant et sur les defauts natifs. La caracterisation des couches s'est faite par differentes techniques : microscopie electronique a balayage (meb), absorption infrarouge (ir), diffusion raman, resonance paramagnetique electronique (rpe), diffraction x, et mesures electriques i(v,t). Les resultats obtenus montrent que les couches polycristallines et monocristallines de diamant ont un comportement similaire, ce qui indique une influence faible des joints de grains. Les mesures de diffusion raman, de diffraction x et de rpe ont montre que l'incorporation de bore dans les couches polycristallines (jusqu'a quelques 10#1#9 cm#-#3) decroit la concentration de defauts natifs. Dans cette gamme de dopage, la qualite des films homoepitaxies est meilleure que celle du substrat. Les mesures d'absorption infrarouge a 300k ont permis de calculer la concentration en bore dans la phase solide, et de mettre en evidence l'inhomogeneite de l'incorporation de bore dans les couches polycristallines. Les faibles concentrations de defauts de type n compensateurs (< quelques 10#1#5 cm#-#3) ont ete deduites des mesures de resistivites et de leurs energies d'activation a haute temperature. Ce dernier resultat est tres prometteur pour les applications electroniques.

The master thesis dealing with problematic about durability of concrete, with use of recycled concrete and addition of silica additions. Predominant for resistance of concrete constructions is surface layer, through which aggressive gasses and liquids penetrate from surrounding environment. The most important indicator of concrete durability is ability of surface layer transmissions of aggressive substants. In experimental part will be defined the actual state of surface layer by normal testing methods. The transmissions of surface layer will be tested on concrete cubes. Tests for transmissions of air (method TORRENT), of water (method ISAT), of acid gases (dept of carbonation by quick test in 98% CO2) will be carried out and also strength tests. Assessment of positive or negative influence of additions and amount of cement on durability and mechanical properties of concrete will be discussed in conclusion.

Hårdgörning av trä syftar till att göra materialet hårdare. Detta går att åstadkomma genom komprimering, det komprimerade materialet tenderar dock att återgå mot sin ursprungsform då materialet utsätts för fukt om ingen låsning sker. Låsningen kan ske mekaniskt i en treskiktskonstruktion som motverkar träets fuktrörelser. Dessa skivor har dock visat sig vara instabila och tidigare försök har uppvisat deformationer i form av kupning. Denna undersökning syftar till att utreda förutsättningarna för att använda komprimerad asp samt att ta fram underlag för framtagning av en kommersiell produkt.

Praktiska tester har genomförts för att studera hårdhet, återfjädring och densitet hos det komprimerade virket. Vidare har treskiktsskivor tagits fram för att testa om det går att få en stabil konstruktion genom att variera tjockleken på spärrskiktet. Även skillnader i acklimatiseringstid och fuktkvotens inverkan för virkets återfjädring har studerats.

Resultaten visar på att aspens hårdhet efter komprimering blir i samma nivå som bok och ask, en låg fuktkkvot vid komprimering av materialet ger en låg återfjädring, komprimerat material har en längre acklimatiseringstid till jämviktsfuktkvot och materialet går att låsa tvärs fiberriktningen i en treskiktskonstruktion.

To make wood harder it can be densified. This can be achieved by compression, the compressed material tends to return to the original shape when it is exposed to moisture fluxations and if no form of fixation occurs. The fixation can be done mechanically in a three-layer panel construction which reduce movements in the timber. These panels have been found to be unstable and previous attempts have shown deformations in form of cupping. This study aims to evaluate the conditions for using compressed aspen wood, and to provide a basis for development of a commercial product.

Practical tests have been conducted to study hardness, springback and density of the compressed wood. In addition, three-layer panels have been developed to test whether it is possible to have a stable construction by varying the thickness of the buttom layer. Differences in acclimatisation time and the moisture contents effect on the springback has aslo been studied.

The results show that the hardness of aspen wood after compression is in equal levels with beech and ashes, a low moisture contet provides a low springback, compressed timber have a longer time for acclimatisation and it is possible to fixate the material in the direction across the grain in a three-layer panel construction.

碩士
國立中央大學
太空科學研究所
96
The earlier study of the additional layer (F3 layer) was primarily focused on simulation and stationary observation from ionosonde. The additional layer phenomenon can only be observed from the station near magnetic equator, and so the physical mechanism is concluded mainly by the E×B vertical drift and meridional neutral wind. In this paper we use FORMOSAT-3/COSMIC radio occultation observations to demostrate the additional layer from September 2006 to August 2007. There are two types of these additional layers, which are foF2foF3. We have computed two types of monthly averages of two type foF3 and hmF3 values, and demostrate their global distributions and happening time. The results can be used to obtain the seasonal variations. And we have verified the relationship of the additional layer to the parameters of F10.7 and Kp. Finally, the monthly averages of foF3 and hmF3 are compared with the ionosonde observations at Fortaleza (38°W,4°S). The respective distribution time of these two types of additional layer is also compared with earlier simulation to see if they are relative.

碩士
國立雲林科技大學
技術及職業教育研究所
102
Math is the mother of all sciences. Teaching and learning math plays an important role in global issue. The study aimed to apply software “LayerMap Player” to elementary school math teaching unit. Surveys were undertaken from an elementary school; with empirical research, to investigate stuents’ math addition learning achievements with LayerMap Player. The research tools adopted in the study were” quasi-experimental designs” . The experimental subjects are two classes of fist-grade-student at an elementary school in Yunlin county. They experimental group which accepted the teaching tool with “LayerMap Player” and the other one is controlled group which acceptd traditional teaching. Two groups were accepted two different instructions during twelve periods, eighty minutes each period. In this study, adaptation of "Addition Learning Achievement " test and “Math Learning Attitude” scale as a research tool; through expert examination to obtain the appropriate reliability and validity, then the conduct of its conduct before and after the test. The research data were analyzed by descriptive statistics, T-test, ANCOVA. The results were as follows: 1. Applying LayerMap Player in 1st-grade-student math teaching can make prominent progress in students’ learning achievement and retention effects. 2. Applying LayerMap Player in 1st-grade-student math teaching can make prominent progress in low- achieving and male students’ learning achievement and retention effects. 3. Applying LayerMap Player in math teaching can make prominent progress in 1st-grade-student math learning attitude.

碩士
大同大學
材料工程學系(所)
96
Four kinds stainless steel designated AISI 316, 410, 430 and SAF 2205 were plasma nitrocarburized for investigation of their electrical resistance, microstructure and hardness distribution of the hardened layers. Plasma nitrocarburizing at low temperature of 420°C with an active screen applied in the process produced a single phase nitrided layer of nitrogen and carbon expanded austenite (S phase) on the specimen surface, which considerably improved the resistivity property of AISI 316 austenitic stainless steel. According to the phase, γ’-Fe4N and ε-Fe2-3N, dominated in the nitcarburized layer, the resistivities of plasma nitrocarburized 410 and 430 specimens are higher than those of the substrate.

碩士
國立東華大學
材料科學與工程學系
102
The focus of this study is on electrochemical deposition of copper oxide for solar cell applications, and the effect of the additional titanium oxide layer on the solar cell efficiency. We successfully fabricated copper oxide thin film solar cells, with the efficiency as high as 2.49%. The efficiency is further enhanced to 2.94% after the addition of the titanium oxide layer. This type of solar cell possess a characteristic I-V curve which is different from that of a regular solar cell. The curve shows that the current first increases then decreases with applied bias, as the bias voltage increases from 0 V to the open-circuit voltage of the solar cell. We successfully deduced a model of the alignment of the energy band diagram which is the only possible explanation of the characteristic I-V curve. The titanium oxide layer, in additional to its light wave-guiding characteristic, is very possible to slow down the mobility of carriers in the electrolyte solution by its nano-sized porous structure, so to reduce the carrier recombination rate of carriers at the copper/electrolyte solution, and to enhance the solar cell efficiency. We found that the contact between electrolyte solution and metallic copper is a necessary prerequisite for the solar cell to be functional. To solve the leakage problem caused by the liquid electrolyte solution, we replaced it with gel electrolyte solution and successfully assembled the quasi- solid-state solar cells. Furthermore, we also discussed the effects of thin film annealing temperature and electrochemical deposition time on the solar cell efficiency, and compared the difference between the two processes of continuous deposition and pulsed deposition.

Tese de mestrado, Medicina Dentária, Universidade de Lisboa, Faculdade de Medicina Dentária, 2014
A new generation of one-bottle self-etch dental adhesives is currently being used. The literature refers to them as universal or multi-mode adhesives. Universal adhesives are indicated as either self-etching or etch-and-rinse adhesives. Some clinical studies and laboratory evaluations have been performed, in fact, demonstrating that some universal adhesives may perform at the same level of previous adhesives. Purpose: To evaluate the effect of an additional hydrophobic resin layer (Adper Scotchbond Multipurpose) on the resin-dentin bond strength (_TBS), of the universal adhesive Scotchbond Universal used in a self-etch mode compared to the manufacturer’s instructions. Materials and Methods: A total of six extracted human teeth (n=6) were randomly distributed between two groups for bond strength testing, according to the different adhesive strategy used: Scotchbond Universal applied as a one-step self-etch adhesive as per manufacturer’s instructions (SBU SE D) and Scotchbond Universal applied as a one-step self-etch adhesive followed by one layer of the hydrophobic resin Adper Scotchbond Multipurpose. After composite restoration, specimens composed of sticks with 1mm2 were stored in distilled water (37ºC/24h) and then tested at 1mm/min using micro-tensile tests (_TBS) to assess dentin bond strength. Failure modes were analyzed under a stereomicroscope. Data were analyzed with a parametric pairedsample t-test since the assumptions of normality were valid. Results: For dentin, the use of a hydrophobic resin layer (SBU+A SE D) resulted in a statistically significantly higher mean μTBS value (38,59 ± 22,21 MPa) than the SBU SE D group (27,66 ± 13,22 MPa), (p<0,05) with a 95% confidence interval. Conclusions: Within the limitations of this in vitro study, it can be concluded that the use of a hydrophobic resin layer may be beneficial to the resin-dentin bond strength when applied to dentin with the self-etch mode. Keywords: universal adhesives; self-etch; hydrophobic resin coat; micro-tensile bond strength.

The applicability of low-pressure membranes systems in distributed (point of use) water treatment is hindered by, among other things, their inability to remove potentially harmful viruses and ions via size exclusion. According to the USEPA and the Safe Drinking Water Act, drinking water treatment processes must be designed for 4-log virus removal. Batch experiments using magnetite nanoparticle (nano-Fe 3 O 4 ) suspensions and water filtration experiments with Polysulfone (PSf) membranes coated with nano-Fe 3 O 4 were conducted to assess the removal of a model virus (bacteriophage MS2). The membranes were coated via a simple filtration protocol. Unmodified membranes were a poor adsorbent for MS2 bacteriophage with less than 0.5-log removal, whereas membranes coated with magnetite nanoparticles exhibited a removal efficiency exceeding 99.99% (4-log). Thus, a cartridge of PSf membranes coated with nano-Fe 3 O 4 particles could be used to remove viruses from water. Such membranes showed negligible iron leaching into the filtrate, thus obviating concern about colored water. Further research is needed to reduce the loss of water flux caused by coating.

Despite years of research in high speed boundary layer flow, there is still a need for insightful experiments to realize key features of the flow like boundary layer response to different conditions and related transition mechanisms. Volumes of data on the these problems point to the fact that there is still much to be understood about the nature of boundary layer instability causing transition and growth of boundary layer in different conditions. Boundary layer stability experiments have been found to be more useful, in which the boundary layer is perturbed and its behavior observed to infer useful conclusions. Also, apart from the stability part, the effect of various changes in boundary layer due to the perturbation makes interesting observation to gain more insight into the understood and the not so understood facets of the same. In view of the above, the effect of a steady axisymmetric thermal bump is investigated on a hypersonic boundary layer over a 60º sharp cone cylinder model. The thermal bump, placed near tip of the cone, perturbs the boundary layer, the behavior of which is observed by recording the wall heat flux on the cone and cylinder surface using platinum thin film sensors. The state of the boundary layer is qualitatively assessed by the wall heat flux comparisons between laminar and turbulent values. The same thermal bump also acts as a heat addition source to boundary layer in which case this recorded data provides a look into the effect of the heat addition to the wall heat flux. To gain a larger view of heat addition causing changes to the flow, effects of change in enthalpy are also considered. Experiments are performed in the IISc HST2 shock tunnel facility at 2MJkg−1 stag-nation enthalpy and Mach number of 8,with and without the thermal bump to form comparisons. Some experiments are also performed in the IISc HST3 free piston driven shock tunnel facility at 6MJkg−1, to investigate the effect of change in stagnation enthalpy on the wall heat flux. To support the experimental results theoretical comparisons and computational studies have also been carried out. The results of experiments show that the laminar boundary layer over the whole model remains laminar even when perturbed by the thermal bump. The wall heat flux measurements show change on the cone part where there seems to be fluctuation in the temperature gradients caused by the thermal bump, which decrease at first and then show an increase towards the base of the cone. The cylinder part remains the same with and without the thermal bump, indicating heavy damping effects by the expansion fan at cone cylinder junction. A local peak in wall heat flux is observed at the junction which is reduced by 64% by the action of the thermal bump. The possible reason for this is attributed to the increased temperature gradients at the wall due to delayed dissipation of heat that is accumulated in the boundary layer as a result of the thermal bump action. The comparison of data for enthalpies of 2MJkg−1 and 6MJkg−1 show that there are negligible real gas effects in the higher enthalpy case and they do not affect the wall heat flux much. Also it is found that the thermal bump fails to dump heat into the flow directly though it creates heat addition virtually by mere discontinuity in the surface temperature and causes temperature gradients fluctuation in the boundary layer. Considering the thermal bump action and the change in stagnation enthalpy of the flow, there seems to be no change in both cases that can be attributed to a common observation resulting from the factor of change in heat inside the boundary layer.

碩士
國立中興大學
化學工程學系所
105
In this study, cellulose (hydroxyethylcellulose, HEC) was used as an additive and doped into perovskite precursor solution to improve the crystal sizes of perovskite layer and photovoltaic (PV) performances of perovskite solar cells (PSCs). By adjusting doped content of HEC and thermal annealing temperature of perovskite layer, to obtained shiny smooth perovskite films with excellent electronic quality, avoiding the creation of unwanted defects during crystallization process, for example, pinholes and grain boundaries. The arichitecture of HEC based inverted PSC was ITO/PEDOT:PSS/Perovskite:HEC/PC61BM/Ag. The power conversion efficiency (PCE) of 8.96%, a short-circuit current density (Voc) of 0.88 V, a short-circuit current (Jsc) of 15.23 mA/cm2, and a fill factor (FF) of 66.8% were obtained for the HEC based PSC. In addition, chloro-deoxy-hydroxyethylcellulose (CDHC) and bromo-deoxy-hydroxyethylcellulose (BDHC) were synthesized and used as the additives of perovskite layer. PV properties of CDHC and BDHC incorporated PSCs were better than that HEC incorporated PSC. The presence of chloride and the bromide ions in the perovskite layer suppressed the crystalline rate of perovskite, whih result in the larger size of crystals in the perovskite layer. This is due to the difference of electron negativity between chloride (or bromide) ion of celleulose derivative and iodide ion of PbI2. The highest PCE (11.03%), Voc (1.01V), Jsc (17.57mA/cm2), and FF (62.1%) were obtaind for the CDHC incorporated PSC.

碩士
國立臺灣科技大學
化學工程系
98
The purpose of this study intends to use different methods to improve the anode and cathode for improvement of cell performance of single-chamber solid state oxide fuel cell (SC-SOFC). To reach the goal, Sm0.5Sr0.5CoO3 (SSC)/ Sm0.2Ce0.8O1.9 (SDC) of different ratios, particle size and composition of the multi-layer cathode was investigated. For anode, diverse ratio of NiO and SDC, pore former (graphite) for preparation of anode functional layer were considered for multi-layer electrode purpose. In addition, the influence of precious metal (Pd, Rh) added in each anode layer was realized. The as prepared anodes and cathodes were characterized by scanning electron microscope (SEM), AC impedance and electrochemical analysis. The performance of the cell was examined at the temperature range of 500-700℃. Methane and air were used as fuel resource and the ratio of volume flow rate is 2:1. 　　First of all, the experimental results show that the best composition ratio for the both NiO/SDC anode and SSC/SDC cathode were 7:3. It is also noted that the cathode made of diverse particle size as well as functional graded SSC (content in four-layer cathode and the particle size in 1st layer is smaller than others) shows better performance than that of homogeneous layer does. For SSC-SDC cathode, the maximum power density of the cell of four layer electrode with smaller particle size for first layer was able to deliver 414.39 mW/cm2 at 600℃. For NiO-SDC anode, a three-layer of various particle size and porosity-graded structure were superior to a homogeneous one. It was found that the maximum power density of cell with three-layer electrode of anode functional layer (AFL) could reach 478.06 mW/cm2 at 600℃. 　　Finally, the benefit of the addition of noble metal to the anode is demonstrated. Pd was added to the middle and outer layers of the three-layer anode. It is found that the maximum power density was 535.86 mW/cm2 with 7 wt% Pd at 600℃. However, carbon deposition on the anode surface was not able to be avoided. Once Pd was incorporated into the other layer attached to the electrolyte, reduction of the cell performance was found. For addition of Rh to the anode side, similar power density of 520 mW/cm2 was obtained with only Rh loading of 0.3 wt% at 600℃. Surprisingly, no carbon deposition was found on the anode.

碩士
中興大學
土木工程學系所
102
In this work, biomolecules/inorganic nanohybrids involving the intercalation of biosurfactants (surfactin) into layered clay layered double hydroxides (LDHs) prepared by an ionic exchange reactions were included. These materials were further investigated in the enhanced production of surfactin from Bacillus subtilis CWS1 fermentation with addition of LDHs. Biosurfactants are amphiphilic molecules produced by microorganism, and capable of reducing surface and interfacial tension. Surfactin was a cyclic lipopeptide consisting of seven amino acids, which is characteristic of high surface activity, low toxicity, biodegradability and ecologically friendly. Mg-Al LDHs were a family of anionic clays with respect to the presence of positive ion charges on the layer surface, and can be intercalated with various molecules. The surfactin intercalation involves an ionic exchange reaction of LDHs at 25℃ and under N2 atmosphere in an aqueous solution to afford a series of biomolecules-LDHs with a maximal basal spacing of 16.8 A from original 7.7 A ,revealed by XRD analyses. The unusually wide interlayer spacing was ascribed to the self-alignment of the biomolecules in the layer confinement, revealed from organic/inorganic fraction by using thermal gravimetric analysis (TGA) and HPLC analysis. The process of embedding biomolecules into the clay gallery provides a new method for synthesizing biomaterial/LDHs hybrids potentially useful in agriculture or biomedical design. Next, enhanced production of surfactin from Bacillus subtilis CWS1 fermentation with LDHs were investigated. Various types of additives, including montmorillonite (MMT) and activated carbon, were added into main culture to improve the surfactin production, revealed that LDHs was the best additives. The culture time with addition LDHs was observed at initial cell growth stage with good surfactin yield. It was also found that the best culture time were five days to produce surfactin. Surfactin yield with 3789 mg/L were obtained at 2 g/L LDHs content, revealing 3.8 times compared with original yield without LDHs addition. This study provided the way toward improving surfactin production from Bacillus subtilis CWS1 more efficiently through LDHs-stimulating fermentation.

碩士
國立中興大學
化學工程學系所
103
Surfactin, one of the biological surfactants was found to possess great potential in biomedical and plant disease application. However, information about the production and purification condition is still limited. In the previous study, the addition of Mg-Al-nitrate LDHs in the liquid culture of Bacillus subtilis CWS1 could significantly increase the surfactin production This study includes two part. In the first part, XRD (X-ray diffractometer) was used to measure the basal spacing of LDHs. The surfactin intercalation involves an ionic exchange reaction of LDHs at 25℃ and under N2 atmosphere in the aqueous solution could yield a series of biomolecules-LDHs with basal spacing ranging from 7.8 Å of 16.1 Å, revealed by XRD analyses. The wide interlayer spacing might be attributed to the self-alignment of the biomolecules in the layer confinement, as analyzed the components by HPLC. In addition, SEM (scanning electron microscope) and EDX (Energy-dispersive X-ray spectrometry) was used to verify the adsorption of surfactin. The process of embedding biomolecules into the clay gallery provides a new method for synthesizing biomaterial/LDHs hybrids potentially useful in agriculture or biomedical design. In the second part, different LDHs, Mg-Al-nitrate LDHs and Mg-Fe-nitrate LDHs, were used as additive to the cultivation of Bacillus subtilis CWS1. In our study, 6 g/L of Mg-Al-nitrate LDHs addition gave the maximum surfactin production of 3789 mg/L after five days culture. However, 4280 mg/L of surfactin was produced in one day culture when 6 g/L of Mg-Fe-nitrate LHDs was added to the cultivation. The maximum production of 5130 mg/L was obtained in four days cultivation. These results indicated that addition of Mg-Fe-nitrate LHDs in Bacillus subtilis CWS1 culture could effectively enhance the production of surfactin. As seen from the time course of the cultuvation, we could found out Mg-Fe-nitrate LHDs addition was found harmless to Bacillus subtilis, the production of surfactin was kept in a dynamic equilibrium. This study provided an approach for improving surfactin production from Bacillus subtilis CWS1 via the addition of Mg-Fe-nitrate LDHs as a stimulator.

碩士
國立中正大學
化學工程研究所
103
With the development of miniaturization in electronic products, ENIG has been regarded as a surface treatment in recent years. The black pad problem was usually occur in ENIG technique and Ni will dissolve into the solder under electron current stressing, the electroless Pd can solve the black pad problem and has better wettability. In this research, we thickened Pd layer and investigated inhibition of electromigration failure by introducing PdSn4 layer in lead-free solder joints. Originally the reaction was formed PdSn4 phase, but Ni was dissolved in the reflow process. So PdSn4 phase was transformed into NiSn4 phase. When the reaction time reached to 4 days, the reaction phase is as the same as solid/solid reaction at the interface 1. At the interface 2, the Ni3Sn4 phase was formed. Because of the fast consumption of Ni substrate, voids exist at the irregular interface 2 and a lot of NiSn4 phase was drifted to the Sn solder. This result was similar to the previous electromigration study on the Sn/Ni system. Therefore, using thin Pd layer could not retard Ni diffusion either. As the thickness of Pd layer increased to 3μm, the layered structure NiSn4 phase was maintained when the reaction time reached to 5 days. But when reaction time increased to 10 days, much Ni substrate was consumed. The enough Pd content can be difficult to be affected by the current stressing but was easily affected by the Ni substrate, so this study used Cu layer to protect the Pd layer. When reaction time reached to 10 days, the reaction phase, PdSn4, remained layered structure. However, when it converted to NiSn4 phase, the Ni atoms were migrated into the Sn solder by interstitial diffusion and grain boundary diffusion. In summary, the PdSn4 phase was a good diffusion barrier. The Pd plating has a significant impact on the solder joints. In the second part, we studied the solid/solid and liquid/solid reactions between the trace added Ga solder and Cu or Ni substrate. For solder within low concentration of Ga, the reaction phase did not change. When the Ga concentration increased, its reaction phase was converted to Cu-Ga and Ni-Ga phase which had good inhibitory in the initial reaction period, but when reaction time increased, the phase was converted to Cu-Sn and Ni-Sn phase. At that time, there was no suppression effect on the reaction rate. At the Ag (10μm)/Cu case, the reaction phase was dissolved at the interface quickly during liquid/liquid reaction. During the solid/solid reactions, the Ag3Sn phase which can do a diffusion barrier was formed at the interface. In Co and Pd case, liquid/solid and solid/solid reaction, the CoSn3 phase was formed when the solder has low concentration of Ga. With the concentration of Ga increasing, the CoSn3 phase generation rate decreased. For higher concentrations of Ga, the CoSn3 phase was transformed into the CoGa phase and the reaction rates were extremely slow. When changing into the Pd substrate, the PdSn4 phase was formed in the reactions and the reaction rate of the PdSn4 phase decreased with the concentration of Ga increasing. These results suggested that Ga in solder had bad suppressed IMC effect at the Cu and Ni substrate, but had good suppression effect at the Co and Pd substrate.

碩士
遠東科技大學
機械工程研究所在職專班
107
In this study, Stellite6 alloys were respectively overlaid on spheroidal graphite(SG) cast irons with 3.0 wt% carbon and 2.8 wt% silicon by plasma transferred arc (PTA) process in the fixed overlaying speed, travel speed and overlaying current by changing the additive content of NbC in the Stellite6 alloys. To explore its influence on the solidification structure of the overlayer and the interface region. In the study, we also used the overlayer with the NbC additve in cobalt-base superalloys for the cutting wear test to explore the effects of different the additive content of NbC in the Stellite6 alloys on the microhardness, the amount of carbides and the cutting wear characteristics of the overlayer. The results reveal that the Stellite6 overlayer melted on SG cast iron with 3.0 wt% carbon and 2.8 wt% silicon under overlaying current (I=100A) is a dendritic structure with M7C3 and M23C6 carbides and matrix structure is -Co. The micro-hardness (Hv) and bulk hardness (HRC) of the overlayer increases with the addition amount of NbC. The results of the cutting wear test show that the flank wear of the Stellite6 cobalt-based alloy overlayer does not increase with the addition of NbC, but it is found that when 30 wt% NbC carbide is added, that have better wear resistance. In the cutting wear test, the wear mechanisms of overlayers are mainly plastic groove, surface polish and adhesive wear as adhered to overlayers. Others minor mechanicsms include brittle crack and fracture. Among these, the case to plastic groove includes microcutting and plough. Keywords: plasma transferred arc, overlaying current, Stellite alloy, spheroidal graphite cast iron, wear .

碩士
國立臺北科技大學
化學工程研究所
96
The goal of this study is to investigate the effect of inorganic layered silicate addition on the thermal stability of water-based coating, and also to discusse the influence of layered silicate addition on thermal stability and flame resistant properties of water-based fire-proof coating. The intumescent fire retardant, used to prepare water-based fire-proof coated, contains pentaerythritol, ammonium polyphosphate and malamine. Effect of layered silicate addition on the thermal stability of water base coating and fire-proof coating was investigated by thermogravimetric analysis (TGA). Cone calorimeter was employed to evaluate the efficiency of layered silicate addition on reducing heat release rate and extinction coefficient of water-based fire retardant coatings. Results from TGA analysis pointed out that second segment step degradation temperature of EVA water-based coating was significantly elevated by adding small amount of silicate clay or montmorillonite.Data from cone calorimeter analysis also showed that addition of silicate clay or montmorillonite can reduce maximum heat release rate of water-based fire-proof coating significantly.

碩士
國立清華大學
化學工程學系
101
Abstract Polymer solar cells (PSCs) are a promising alternative for low-cost renewable energy due to their solution-process ability, flexibility and large-area fabrication. However, the power conversion efficiency (PCE) of PSCs depends on complicated mechanism of carrier generation and transport. In general, the morphology of active layer in PSCs plays a very important role in PCE. Many reports have studied on effective control of morphology but its characteristics are depending on active polymer, making it difficult to establish a general method for controlling the morphology. Multi-fluoro-substituted benzene has the nature of electron-depleted ring center since the electron withdrawing characteristic of the F-substituents makes the electron density of benzene ring moving to F atoms in the periphery. Thus, multi-fluoro-substituted benzene has the capability to strongly interact with electron-rich species such as double bonds and aromatic rings. Based on this concept, we propose two methods to improve the device performance by controlling morphology of the active layer. The first method is to add a multi-fluorobenzene substituted polymer, poly(pentafluorophenyl methacrylate）(PFPPA), into active layer as additive. The multi-fluorobenzene can attract the [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and make it align along with the main chain of the PFPPA. The aligned PCBM makes the electron transport easier and thus the PCE is improved from 3.43 % to 3.74 %. The second method is to modify ZnO surface by incorporating 2,3,5,6- Tetrafluoro-1,4-benzenedicarboxylic acid (TFTPA) on top of it. Upon coating a layer of fullerene derivative on top of it, the fullerene molecules can be physically absorbed via coulombic interaction and facilitate a promoted electron collection from the bulk. Significant enhancement in PCE is observed for the devices with the active layer P3HT:PC61BM (or PC71BM) by promoting from 3.20 to 4.03% (or from 3.27 to 4.04%); and with the active layer PTB7: PC71BM from 6.03 to 6.90 %. This method should be also applicable to other types of active layer.

碩士
國立成功大學
機械工程學系
107
For the first experiment, nine specimens are prepared on the basis of the L9(33) orthogonal array design to evaluate the optical and electrical properties, morphology, and the microstructure of a-IGZO/Ag/a-IGZO (IAI) triple-layer composite films deposited on curved glass substrates with different radius of curvature efficiently. The experiments are arranged for the changes in three controlling factors, namely the IGZO and Ag thicknesses, and substrate’s radius of curvature. Radius of curvature has the highest contribution for the RMS surface roughness (SRq) and the mean particle size (PS). The carrier mobility (CM) and carrier concentration (CC) are proportional to each, irrespective of the controlling factor change in this study. An increase in the radius of curvature can result in the increases of SRq and PS, and therefore brings in a surface scattering effect which can cause the reduction of CM as well as the rise of resistivity (R). In addition, a sufficiently large radius of curvature can elevate the transmittance at 550 nm and Haack’s figure of merit (FOM) effectively, but it can lower the reflectance of blue, green and red. Via the carrier injections, increasing the Ag thickness can elevate the carrier mobility and concentration significantly. The reflectance for blue, green, and red are also risen by increasing the Ag thickness. As a result of Burstein-Moss effect, carrier concentration and optical bandgap are elevated by increasing the IGZO thickness. Additionally, the reflectance of blue, green, and red are also risen. Appropriate choices in the IGZO and Ag thicknesses and the radius of curvature can obtain the transmittance 〉80 %, and elevate the FOM significantly. For the second set of experiments, AZO and AZO/Ag/AZO (AAA) specimens are prepared by varying O2 and N2 flow rates to investigate the gas effects on the microstructure, and the optical and electrical properties. The AZO specimens are found to have the decreases in grain size and SRq, and an increase in the compressive residual stress when N2 flow rate increases higher than 2.5 sccm. The addition of O2 can contribute to a similar tendency for grain size, SRq and residual stress; the grain size and SRq are always smaller, while residual stress is larger than that prepared with N2. The thickness of AZO is proportional to the grain size and SRq, whereas it is inversely proportional to the residual stress of AZO, they are valid for both AZO and AAA thin films. Specimen D with 60-nm AZO thickness possesses the strongest anti-reflection effect of the AAA structure, and therefore suppresses the reflection from the Ag interlayer significantly. P-type conductivity is achieved by introducing the N2 into AZO layers. The carrier mobility and carrier concentration are lowered by increasing the amount of O2 because the oxygen vacancies are reduced. The Burstein-Moss effect is observed for the n-type AAA thin films where a decrease in optical bandgap along with an increase in carrier concentration is found for the p-type AAA films. Specimen D possesses the highest FOM value and relative high T at 550 nm because the 60-nm AZO can contribute to the strongest anti-reflection effect.

Ce mémoire porte sur les mécanismes de relaxation et de fuite des excitons dans des systèmes de boîtes quantiques(BQs) d’InAs/InP. Les systèmes sont composés d’un sub- strat volumique d’InP, appelé matrice (M), d’un puits quantique d’InAs, nommé couche de mouillage (CM), et des familles de BQs d’InAs. La distinction entre les familles est faite par le nombre de monocouche d’épaisseur des boîtes qui sont beaucoup plus larges que hautes. Une revue de littérature retrace les principaux mécanismes de relaxation et de fuite des excitons dans les systèmes. Ensuite, différents modèles portant sur la fuite thermique des excitons des BQs sont comparés. Les types de caractérisations déjà produites et les spécifications des croissances des échantillons sont présentés. L’approche adoptée pour ce mémoire a été de caractériser temporellement la dynamique des BQs avec des mesures d’absorbtion transitoire et de photoluminescence résolue en temps (PLRT) par addition de fréquences. L’expérience d’absorption transitoire n’a pas fait ressortir de résultats très probants, mais elle est expliquée en détails. Les mesures de PLRT ont permis de suivre en température le temps de vie effectif des excitons dans des familles de BQs. Ensuite, avec un modèle de bilan détaillé, qui a été bien explicité, il a été possible d’identifier le rôle de la M et de la CM dans la relaxation et la fuite des excitons dans les BQs. Les ajustements montrent plus précisément que la fuite de porteurs dans les BQs se fait sous la forme de paires d’électrons-trous corrélées.
This thesis focuses on the mechanisms of relaxation and leakage of excitons in systems of quantum dots (QDs) InAs / InP. The systems are composed of a substrate of InP volume, called matrix (M), of a quantum well of InAs, named wetting layer (CM), and of QD families of InAs. The distinction between the families can be explained by the number of monolayer-thick boxes that are wider than high. A literature review highlights the main relaxation mechanisms and leakage of excitons in systems. Then, different models on the thermal leakage of the QD excitons are compared.Then, a presentation of the different types of characterizations already and of the specifications on the samples growths. The approach used for this thesis is to temporarily characterize the dynamic of the QDs with transient absorption and upconversion. The transient absorption experiment’s results are not very convincing, but are minutely explained. PLRT measures were used to follow in temperature the excitons effective lifetime in the QDs families. Then, with a detailed balance model, which has been well explained, it was possible to identify the role of theMand CM in relaxation and leakage of excitons in QDs. As shown by the adjustement, the escape of carriers in the QDs is made in a correlated electron-hole pairs form.

碩士
國立中正大學
化學工程研究所
106
Double-layered scaffolds supported differentiation of induced pluripotent stem cells (iPSCs) becoming a flourishing and potential approach for artificial pancreas. This work aims to seed iPSCs on gelatin (Gel)-alginate (Alg)-hyaluronic acid (HA) double-layered scaffolds containing inverted colloidal crystals (ICC) and to investigate cell proliferation and pancreatic differentiation of iPSCs. Gel-Alg-HA double-layered scaffolds were prepared by using ICC method via crosslinking with CaCl2, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC), and N- hydroxysuccinimide (NHS). The pore surface of Gel-Alg-HA double-layered scaffolds were grafted with growth differentiation factor-8 (GDF-8) and Wnt3a and treated with retinoic acid (RA) and noggin to improve the differentiation of iPSCs towards endodermic cells followed by pancreatic cells. An increasing weight percentage of Gel increased the adhesion efficacy of iPSCs. Moreover, Alg and HA help to promote the proliferation and survival rate of iPSCs, which make higher availability of iPSCs for differentiation into pancreatic cells. Immunofluorescence staining images evidenced that Gel-Alg-HA double-layered scaffolds grafted with GDF-8 and Wnt3a enhanced the differentiation of iPSCs into endodermic cells and followed by treatment with RA and noggin improved the differentiation of endodermic cells into pancreatic cells. The proper control over the physical and biomedical properties of the Gel-Alg-HA double-layered scaffolds could guide iPSCs to differentiate into endodermic cells and pancreatic cells for diabetic treatment. Keyword: Induced pluripotent stem cells, GDF-8, Wnt3a, noggin, retinoic acid, inverted colloidal crystals, double-layered scaffolds