Dissertations / Theses on the topic 'Diamond formation'
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Newson, Pamela Lynn. "Studies of diamond film formation." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/30529.
Full textDe, Weerdt Filip. "Spectroscopic studies of defects in diamond including their formation and dissociation." Thesis, King's College London (University of London), 2007. https://kclpure.kcl.ac.uk/portal/en/theses/spectroscopic-studies-of-defects-in-diamond-including-their-formation-and-dissociation(b05e7748-c1ff-4c57-9c24-ec5cb84baddf).html.
Full textSouthworth, R. E. "The behaviour of the stable isotopes of nitrogen during diamond formation." Thesis, University College London (University of London), 2016. http://discovery.ucl.ac.uk/1478224/.
Full textArunagiri, Tiruchirapalli Natarajan. "Interfacial Electrochemistry of Metal Nanoparticles Formation on Diamond and Copper Electroplating on Ruthenium Surface." Thesis, University of North Texas, 2003. https://digital.library.unt.edu/ark:/67531/metadc5526/.
Full textPujol, Solà Núria. "Diverse origin and processes in the formation of diamond and other exotic minerals in ophiolitic chromitites." Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/672455.
Full textEn aquesta tesi doctoral s’investiguen en detall les cromitites ofiolítiques de Cuba Oriental i de Bou Azzer, Marroc, per tal d’identificar la presència de minerals exòtics d’ultra-alta pressió, formats en condicions superreduïdes o derivats de l’escorça continental, i interpretar-ne la formació. Els resultats representen la primera descripció de minerals exòtics en aquestes ofiolites i les respectives discussions han permès descartar condicions d’ultra alta pressió per les cromitites i les roques associades i proposar models de formació simples relacionats amb la serpentinització de la litosfera oceànica pels minerals exòtics. S’ha investigat la interacció de líquids toleítics evolucionats amb cromitites preexistents a la zona de Potosí, Cuba, i es proposa un model de formació en dues etapes: primer la cristal·lització d’un magma de tipus MORB genera, mitjançant cristal·lització fraccionada, magmes residuals enriquits en elements incompatibles, i posteriorment alguns d’aquests magmes residuals s’escapen i reaccionen amb les cromitites. A les cromitites ofiolítiques de Cuba Oriental s’ha pogut identificar diamant, lamel·les orientades de clinopiroxè i de rútil, fases superreduïdes (carboni amorf, moissanita, Si i Cu natiu, aliatges de Fe-Mn) i minerals derivats de l’escorça continental. Els grans de diamant són de mida nanomètrica, es troben en inclusions fluides juntament amb metà, serpentina i magnetita. Totes les evidències indiquen que els nanodiamants es van formar durant la serpentinització en ambients superreduïts en condicions de baixa pressió i temperatura, igual que la resta de minerals superreduïts. En canvi, les lamel·les de clinopiroxè es van formar com a exsolucions degut a la cristal·lització de la cromita i les lamel·les de rútil es van formar per la interacció de les cromitites amb gabres. Finalment, el zircó podria representar material de la placa subduint atrapat pels magmes dels quals va cristal·litzar posteriorment la cromita. La investigació de les cromitites neoproterozoiques de Bou Azzer ha permès determinar la seva formació en una zona d’avant-arc durant l’inici de subducció, diferenciant dos estadis de formació relacionats amb basalts d’avant-arc (FAB) i boninites. Aquestes cromitites contenen inclusions de minerals del grup del platí i de minerals exòtics com són lamel·les de clinopiroxè, moissanita, Cu natiu, diàspora i zircó, similar a les cromitites de Cuba.
Hickey, Diane P. "Ion implantation induced defect formation and amorphization in the Group IV semiconductors: diamond, silicon, and germanium /." [Gainesville, Fla.] : University of Florida, 2007. http://purl.fcla.edu/fcla/etd/UFE0021224.
Full textWalsh, Carl. "Deep ultra-hot Archaean mantle dynamics; highly depleted residues as cradles for mantle diamond." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/235717/1/Carl%2BWalsh%2BThesis.pdf.
Full textIkeda, M., H. Ito, M. Hiramatsu, M. Hori, and T. Goto. "Effects of H, OH, and CH_3 radicals on diamond film formation in parallel-plate radio frequency plasma reactor." American Institute of Physics, 1997. http://hdl.handle.net/2237/7026.
Full textKabbes, Jason E. "Diamond Formation under Lower Mantle Redox Conditions: Experimental Constraints on the Mineralogical Host of Carbon in Earth’s Mantle." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1282152005.
Full textMbayi, Letsema. "Turning rough dreams into a polished reality? : investigating the formation of human capital in Botswana's diamond cutting and polishing industry." Thesis, Open University, 2013. http://oro.open.ac.uk/37431/.
Full textWiest, Landon A. "Formation, Functionalization, Characterization, and Applications of a Mixed-Mode, Carbon/Diamond-Based, Core-Shell Phase for High Performance Liquid Chromatography." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/4239.
Full textCheviot, Maureen. "Chemins cinétiques de formation du diamant microcristallin sur couches minces de nitrure de tantale élaborées par pulvérisation cathodique réactive." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0377/document.
Full textWeight reduction of aeronautic devices raises composite and multi-materialsmachining issues. The challenge lies in designing cutting tools able to resist to the specificmachining conditions of these materials and their abrasivity. One solution is to use diamond as awear resistant coating. In this work, we propose to study the kinetic of formation ofmicrocrystalline diamond onto a tantalum nitride (TaN) thin film. TaN exhibits two crystallographicstructures: the hexagonal stable one, h-TaN, and the metastable one with a face centered cubiclattice, fcc-TaN. An accurate control of deposition conditions allows us to isolate both structuresas single-phased thin films and to propose two stabilization mechanism scenarios. The influenceof each TaN structure on diamond formation has been gauged thanks to the inventivemethodology we developed and which combines experiments and modeling. The contribution ofmodeling relies on an accurate interpretation of the experimental results and the identification ofthe key parameters. Thus, carbon diffusion coefficients and carbon transfers into h-TaN and fcc-TaN phases could be determined. Our results, in terms of TaN/carbon interactions, open up newhorizons for diamond nucleation and growth in CVD conditions
Kolesnikov, Anton. "Experimental investigation of hydrocarbon formation and transformation under Earth´s upper mantle conditions." Doctoral thesis, KTH, Kraft- och värmeteknologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-27017.
Full textQC 20101203
Fousson, Eric. "Formation de diamants par voies dynamiques et leur caractérisation." Mulhouse, 2000. http://www.theses.fr/2000MULH0623.
Full textCensier, Claude. "Dynamique sédimentaire d'un système fluviatile diamantifère mésozoïque : la formation de Carnot, République centrafricaine /." Orléans : Ed. du BRGM, 1991. http://catalogue.bnf.fr/ark:/12148/cb35519227w.
Full textAndré, Bernard. "Formation de dépôts de carbone de type diamant sous bombardement ionique." Grenoble INPG, 1991. http://www.theses.fr/1991INPG0093.
Full textFerroir, Tristan. "Formation et transformations de la matière extraterrestre : grains comètaires et météorites choquées." Lyon, École normale supérieure (sciences), 2009. http://www.theses.fr/2009ENSL0517.
Full textDuring this Ph. D, we were member of the Preliminary Examination Team which studied the chemical ans mineralogical compositions of Stardust mission cometary grains using synchrotron radiation techniques. These studies are of great importance since comets are the most primitives and unmodified bodies of our Solar System. Apart from comets, meteorites are also part of the first solar system stones. Using a very wide range of analytical techniques, we studied the different transformations which take place during a shock event undergone by these rocks. We particulary studied how part of the martian atmosphere was trapped in martian meteorites during their ejection from their parental body. We also studied the different phase transformations during the shock events on three different mineralogical system : olivines, pyroxenes and carbon. We showed that different transformation mechanisms were active in these systems and that a melting step in two of the three cases greatly change our vision in the transformation mechanism from low pressure polymorphs to high pressure polymorphs in meteorites. Moreover, we described a new diamond polytype and a new ultra-hard phase of carbon in ureilites. Finally , we also made in situ studies of the behavior of K-feldspar at high pressure using diamond anvil cell coupled with X-ray diffraction techniques. We showed that the high pressure polymorph, K-hollandite, over goes a phase transition which we discovered and that it seems to be stable as deep as the bottom of the Earth mantle
Martin, Audrey. "Recyclage du carbone et formation du diamant en zone de subduction : contraintes expérimentales." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2009. http://tel.archives-ouvertes.fr/tel-00725967.
Full textLucazeau, Emmanuelle. "Contribution à l'étude de la formation du carbure de molybdène sur le diamant." Grenoble INPG, 1997. http://www.theses.fr/1997INPG0110.
Full textCensier, Claude. "Dynamique sédimentaire d'un système fluviatile diamantifère mésozoïque : la formation de Carnot (République centrafricaine)." Dijon, 1989. http://www.theses.fr/1989DIJOS036.
Full textBenyahia-Bentadjine, Sonia. "Mécanismes de formation et propriétés physico-chimiques et mécaniques des interphases epoxy-diamine/métal." Lyon, INSA, 2000. http://www.theses.fr/2000ISAL0025.
Full textThe interfacial reactivity between epoxy (DGEBA) and diamine (IPD) monomers and metallic substrates (titanium, aluminum and gold) has been studied using various analytical techniques. Chemical, physical and mechanical properties of organic coatings were determined as a function of their thickness and compared to bulk values. An interphase having specific properties and quite different to polymer bulks ones was underlined. Interphase properties were found to be affected by the substrate nature, metallic surface treatments, the diamine nature (whether aromatic, aliphatic or cycloaliphatic) and the stoechiometric ratio of epoxy-amine mixture. Reaction mechanisms leading to the interphase formation were determined by studying "modified" monomers by hydrated oxide layer. It was found that the diamine monomer reacts with the metallic surface and induces a chemical etching. Then metallic ions then diffuse through the organic layer to form metal-amine complexes. When a saturation threshold was reached, crystals of modified monomers were observed at room temperature. These complexes induce phase separation during the cure cycle of the epoxydiamine mixture leading to a new network formation. The understanding of these phenomena, allows us to produce bulk materials having the same properties than thin films or interphase
Charrier, Gaëlle. "Etude de la formation de terminaisons oxygénées et azotées sur diamant par des traitements électrochimiques en milieux aqueux et ammoniac liquide." Versailles-St Quentin en Yvelines, 2013. http://www.theses.fr/2013VERS0009.
Full textSemiconductive diamond presents outstanding properties attractive for numerous applications, from electrochemistry to the immobilization of biomolecules. The nature of the surface terminations strongly influences its chemical and physical properties. Thus, many works are devoted to the modification of the hydrogenated surface groups of as-grown diamond into more reactive oxygenated or nitrogenated ones. In this context, we developped a new method for the oxidation of diamond surfaces at open circuit potential conditions and in the presence of a strong oxidizing specie. This efficient method is easy to perform and leads to the formation of a great amount of “C-O” groups at diamond surfaces without any degradation of the electrochemical properties of the electrodes. New direct amination methods have also been developped using electrochemical treatments in liquid ammonia, leading to the formation of C-NH2 groups and opening the way for many applications, for instance surface post-functionalization with organic molecules. The evolution of the surface chemistry and electrochemical properties of the electrodes during the different treatments has been followed by contact angle measurements, surface analyses (XPS, SEM) and electrochemical characterizations (C-V and I-V with a redox couple)
Sesay, Mohamed Kanja. "La gouvernance sans Etat : une étude de cas sur les territoires contrôlés par le front révolutionnaire uni en Sierra Leone." Thesis, Bordeaux 4, 2013. http://www.theses.fr/2013BOR40043/document.
Full textThe war in Sierra Leone began in 1991 and ended in 2002. Analysts remaindivided on the question of its cause, particularly on the issue of the motivations ofthe rebel Revolutionary United Front (RUF), the armed group which started thehostilities. From its entry into Sierra Leone to date; the RUF has been the subjectof much debate and criticism, both on its organization and its methods of wagingwar. By asking questions relating to the organizational capacity of the RUF, thisstudy aims to contextualize the central arguments often associated with civil warsof the Sierra Leonean kind: they insist on the absence of meaning; these conflictsillustrate a situation of chaos and/or are devoid of political reflections. They arealso the consequence of the absence or failure of a State.This present study continues these discussions in relation to the RUF, bydemonstrating that this guerilla force was not as disorganized as often portrayed,despite increased media coverage on its use of violence. The RUF was not a groupof murderous diamond thieves but also quite structured with a clear hierarchicallogic or ideology. Through this internal organisation, it set up structures toestablish governor/governed relations with urban populations under its control.The rebel force thus established a system to manage these local communities. Suchconsiderations changed the nature of the armed group in the areas under itscontrol, where it established a civil "administrative unit", far from being efficientbut identifiable as such.By juxtaposing the complex interactions of daily governance, the thesishighlights the governance practices of the RUF and the aspects that characterise"normal" life in these « war torn » towns. It analyzes the variables of therelationship between members of the rebel movement occupying these towns andthe local population. Once a town is conquered, the rebels are forced to dosomething there, an "administrative system" establishing an order of coexistence inthe whole area is imposed.The study therefore analyzes the tools of civil governance, mobilized intime of war. During this study, several field research trips to Sierra Leone, wereconducted. These trips have allowed the realization of several interviews,individual and collective. They support the general ideas presented in this thesis
Reich, Blair Jesse Ellyn. "Cyanide-catalyzed C-C bond formation: synthesis of novel compounds, materials and ligands for homogeneous catalysis." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4987.
Full textNaamoun, Mehdi. "Mécanisme de formation et de propagation des dislocations au sein de diamant CVD monocristallin et développement de stratégies visant à réduire leur densité." Paris 13, 2013. http://scbd-sto.univ-paris13.fr/secure/edgalilee_th_2013_naamoun.pdf.
Full textThe main objective of this PhD thesis is to obtain single crystal diamond films with low dislocation density, prerequisite to their use in the field of power electronics. At first, the formation and propagation of these extended defects into single crystal diamond were studied. Two main sources of dislocations have been identified: (i) dislocations directly originating from the substrate (natural or HPHT diamond) that thread through the CVD layer, (ii) and dislocations formed at the HPHT-CVD interface. To eliminate defects of the second origin, surface treatments combining the ICP- RIE process (carried on the upper side) and H2/O2 plasma etching (on the back side and on the lateral faces of the sample) were proposed. Thus, thick CVD layers (> 300 μm) with a reduced defect density (around 104 per cm2) were obtained. To eliminate dislocations directly originating from the substrate, innovative techniques based on the one hand on selective masking of defects by metal particles and on the other hand by the macro and micro-structuration, were developed. Surface macro-structuration demonstrated the ability to change the direction of dislocation’s propagation towards the crystal edges. Selective masking (developed and patented during this PhD thesis) and micro-structuration techniques have shown the ability to reduce dislocation density by preventing them from propagating through the CVD crystal
LUCET, DENIS. "Synthese de substrats et d'inhibiteurs potentiels de la biosynthese de la biotine. Nouvelle methodologie de formation stereoselective du motif diamino vicinal." Paris 11, 1997. http://www.theses.fr/1997PA112033.
Full textMichau, Dominique. "Etude de l'influence du substrat sur la formation de films de diamant : application au développement de couches minces de nitrure de bore cubique." Phd thesis, Université Sciences et Technologies - Bordeaux I, 1995. http://tel.archives-ouvertes.fr/tel-00143406.
Full textWu, Jian-Haur, and 吳健豪. "Diamond Formation By Thermal Activation And HFCVD." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/39611766076840246013.
Full text國立東華大學
材料科學與工程研究所
89
This study on diamond synthesis has been carried out in two ways to achieve methods of high growth rate and of scalable high-volume production. One is by thermal activation of graphite, the other based on hot-filament CVD method. Diamond formation by thermal activation of graphite is a novel technique that synthesize diamond particles at the highest reported growth rate of 100~500 µm/s. We tried to follow the growth method reported by A. V. Palnichenko et al. in Nature 1999. Diamond formation at such a high growth rate is shown in this report. Our samples were analyzed by X-ray, SEM, EDS and Raman spectroscopy. The results show that the main products are diamond-like carbon and graphite, and they are different from the report mentioned previously. We classify the synthesis of diamond by hot-filament CVD into two series. The first one is the influence of hydrogen-storage alloy for diamond formation. The second is observing diamond growth in three-dimensional packing of Ni or Cu net. But the results show no effectively increasing of the diamond growth rate in both ways.
黃弼鑫. "Cold flow analysis of a microwave PECVD for diamond-like thin-film formation." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/09464809373478639660.
Full textFernandes, Joana Cristina Taveira. "Water treatment with boron-doped diamond electrodes – A review on by-products formation." Master's thesis, 2021. http://hdl.handle.net/10362/118283.
Full textA formação e identificação de sub-produtos resultantes da utilização de processos eletroquímicos avançados de oxidação de diamante dopado com boro (BDD), para o tratamento de água, é essencial para a compreensão dos respetivos riscos para a saúde pública e o ambiente. Contudo, apesar da considerável bibliografia relativa à utilização desta tecnologia em tratamento de água, um estado da arte sobre a formação de sub-produtos e respetivos efeitos nocivos nas principais áreas de tratamento de água, ainda não foi elaborado. Esta dissertação tem como objetivo apresentar o conhecimento atual sobre as espécies reativas e sub-produtos formados durante a oxidação eletroquímica com BDD no tratamento de lixiviados de aterro municipal, água residual industrial, água potável, água residual municipal e remoção de micropoluentes. Foram abordadas as principais espécies reativas, nomeadamente, de oxigénio (ROS), de sulfato (RSS), de cloro (RCS) e, outras espécies oxidantes. Relativamente aos sub- produtos identificados, a presença de compostos halogenados e per-halogenados é recorrente nas diferentes áreas de tratamento de água. A concentração dos mesmos foi influenciada por condições experimentais e pelo material do BDD. Consequentemente, para minimizar a formação destes compostos, é recomendável a utilização de um pH ácido, baixa densidade de corrente, concentrações elevadas de cloretos, NaNO3 como eletrólito e evitar o uso de temperaturas baixas (e.g., 5oC). A diminuição da toxicidade com esta tecnologia foi verificada em alguns dos estudos. No entanto, em termos de efeitos tóxicos em mamíferos (i.e., roedores e humanos), existe um número considerável de sub-produtos classificados como possíveis carcinogénicos, disruptor endócrinos e mutagénicos. Esta dissertação contribui para uma melhor compreensão dos sub-produtos formados durante a oxidação eletroquímica com BDD, e proporciona um aumento da consciencialização sobre os progressos a realizar na implementação desta tecnologia em estações de tratamento de água.
Vasilyev, Prokopiy. "The oxidation state of deeply subducted, altered oceanic crust: an experimental study and the evidence from natural samples." Phd thesis, 2016. http://hdl.handle.net/1885/101931.
Full textMakgato, Thuto Nelson. "Formation of surface diamond-like nanostructures on graphite induced by highly charged ion irradiation." Thesis, 2011. http://hdl.handle.net/10539/9249.
Full textWang, Han-Pei, and 王漢培. "The formation of diamond-like carbon (DLC) film in plasma assisted pulsed laser deposition method." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/37557927972738024141.
Full text國立成功大學
機械工程學系碩博士班
96
In this study a technique of deposition by plasma assisted pulsed laser in atmospheric pressure is proposed. The formation of diamond-like carbon (DLC) film has been investigated. This approach is made to accelerate the ablated carbon particles by a high temperature plasma torch, then the kinetic energy of the carbon particle can be increased to form the sp3 atomic structure of the carbon by the plasma flow. The influences of the plasma flow have been examined by numerical analysis and experimental observation. In the numerical analysis, the electromagnetic fields and the distribution of velocity and temperature on plasma flow have been solved by a set of magnetohydrodynamics (MHD) equations with the software FLUENT. The effects on the plasma flow at various parameters, such as electric current and inlet pressure, are discussed in this study. The plasma assisted pulsed laser deposition method was used to deposit DLC film on the steel substrate at atmospheric pressure with the argon gas flow in experiment. According to the results of the carbon film inspected by the Raman spectroscopy, it reveals that the intensity ratio of the D-band to G-band (Id/Ig) of the carbon film can be reduce to 0.513 by the implementation of plasma flow, therefore the DLC film was solidly formed. The adhesive strength of the DLC film was characterized by the scratch test, it can be seen that the critical load of the film is about 19 N, which is acceptable in comparison with other approaches.
Yu, Wen-Hung, and 游文宏. "Influence of tool wear and cutting parameters on the chip and burr formation in diamond turning." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/62372382203760442002.
Full text淡江大學
機械與機電工程學系碩士班
101
Owing to the rapid development in the optical and opto-electronic industries, components/molds with micro patterns are in great demands. Although many approaches can be adopted to generate those micro-structures, precision diamond turning is by far the most commonly used method. However, diamond turning has its own problems to resolve. Micro-burr produced during the micro-cutting process is one of these drawbacks needing further investigation and, a feasible solution. Efforts have been made in this study to analyze the burr formation process in diamond turning by FEM simulation, micro-scratching and diamond turning. Influence of tool wear and cutting parameters such as rake angle, included angle and inclined angle on the chip and burr formation in diamond turning were systematically investigated. The results showed that (i) tool cutting edge sharpness together with tool rake angle and included angle have profound effect on burr formation and achievable surface finish, (ii) simulation can supply very useful information for setting the machining parameters to suppress the burr formation during micro-cutting process.
Barry, Travis. "Genetic Pore Types and Their Relationship to Reservoir Quality: Canyon Formation (Pennsylvanian), Diamond M Field, Scurry County, Texas." Thesis, 2011. http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10536.
Full textLiu, Tao [Verfasser]. "High resolution investigation of texture formation process in diamond films and the related macro-stresses / von Tao Liu." 2009. http://d-nb.info/993966063/34.
Full textKo, Jui-Ling, and 葛瑞齡. "Simulation and experimental analysis of chip and burr formation mechanisms involved in diamond micro-cutting of ductile metals." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/24729019702128623467.
Full text淡江大學
機械與機電工程學系碩士班
100
As the demand for micro-patterned parts getting bigger, the need for molds with micro/nano scaled patterns to duplicate these parts effectively and economically is increasing ever so rapidly. Over the years, numerous attempts have been made to fabricate these molds using various approaches such as lithography, FIB, and precision diamond turning. Amongst these approaches, diamond turning is by far the most commonly used method to generate the micro-patterned rollers for roll-to-roll fabricating of precision optical parts such as BEF and 3D films. However, micro-burrs are frequently producedduring the micro-cutting process which not only makes the mold un-usable but also increases the cost of machining. Since the micro-patterns/burrs are normally in micrometer-scale and the mold is usually too big to put into SEM for close examination, experimentally observation of the micro-cutting process and burr formation is rather difficult and costly.This research aimed to study the chip/burr formationprocess during the micro-cutting by simulation and micro-scratching approaches. Influences of the cutting parameters such as rake angle, inclination angle, tip radius, included angle, cutting speed and cut depthon the chip/burr formation were systematically investigated. The results showed good agreement with the scratching experiments. This means that simulation can supply very useful information for setting the machining parameters to suppress the burr formation during micro-cutting process.
Chen, Wen-Hao, and 陳玟豪. "Influence of tool shape/wear and cutting parameters on the burr formation mechanisms in precision diamond turning of micro-optical structure." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/98070489586825037174.
Full text淡江大學
機械與機電工程學系碩士班
104
As the demand for micro-patterned parts getting bigger, the need for molds with micro/nano scaled patterns to duplicate these parts effectively and economically is increasing ever so rapidly. Over the years, numerous attempts have been made to fabricate these molds using various approaches such as lithography, FIB, laser ablation, and precision diamond turning. Amongst these approaches, diamond turning is by far the most commonly used method to generate the micro-patterned rollers for roll-to-roll fabricating of precision optical parts such as BEF and 3D films. However, micro-burrs are frequently produced during the micro-cutting process which not only makes the mold un-usable but also increases the cost of machining. Efforts have been made to study the burr formation process during the micro-cutting by finite element method based simulation and diamond turning experiments. Influences of the machining parameters such as cutting edge radius, included angle, depth of cut, cutting speed and spiral/plunge-cut approaches on the burr formation were systematically investigated. The results show that (i) cutting edge radius and depth of cut have profound effect on burr formation and (ii) plunge-cut approach performs better than spiral-cut in suppressing the burr formation during micro-cutting process.
CHA, R. Z., and 張仁宗. "The study of phenyl-naphthol diamine formation and its." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/78933963540579900897.
Full text國立中央大學
化學工程研究所
83
4-(3-取代基-4-胺基苯)-2-羥基-奈胺類可以由以下的方法合成、此方法 是將1-(鄰-取代苯)-偶氮-2-奈酚、還原成胼類化合物、然後在溫度為0℃ 時、以鹽酸進行酸重排反應。以4-(4-胺基苯)-2-羥基-奈胺為例:首先由 苯胺經重氮化形成苯胺偶氮鹽於低溫及鹼性條件下、與β-奈酚形成苯-偶 氮-2-奈酚然後再經由鋅粉及醋酸在熱乙醇中還原為 苯-2-奈酚胼、苯-2- 奈酚胼在常溫的空氣中極為不穩定。 4-(4-胺基苯)-2-羥基-奈胺鹽酸鹽( 雙胺Ⅰ)、可以由苯-2-奈酚胼在鹽酸溶液中溫度為0℃時進行酸重排反應 、得到聯苯奈二胺鹽酸鹽、收率為40%、融點大於3000℃。類似的方法、 鄰-甲基苯胺可得到1-胺-4-(3'-甲基-4'-胺基苯)-2奈酚鹽酸鹽、簡稱雙 胺Ⅱ、收率37.5%、融點大於300℃。鄰-甲氧基苯胺、可得到1-胺-4-(3'- 甲氧基-4'-胺基苯)-2-奈酚鹽酸鹽、簡稱雙胺Ⅲ、收率35.6%、融點大 於300℃。合成之聯苯奈二胺之鹽酸鹽與2-奈酚、1-胺基-8-羥奈-3,6-雙 磺酸( H-酸)、6-胺基-1-羥奈-3-磺酸(J-酸)、7-胺基-10-羥奈-3-磺酸( γ-酸)之雙重氮鹽於低溫及鹼性偶合條件下、 得到雙偶氮染料、其水溶 液可視光最大吸收波長為530-641nm、為紅色到藍色溶液。很成功的合成 了非聯苯型之不對稱苯-奈雙胺及其雙偶氮染料。 4-(ortho-substituted-4-amino-phenyl)-2-hydroxy-1-napthyl- amine may be prepared by the following method, which consists in reducing 1-(ortho-substitutued-phenyl)-azo-2-naphthol to the hydrazo compound, and then acid rearrangement with hydrochloric acid at 0℃。 phenyl-azo-2-naphthol was at first prepared by copling dia- zotised aniline with β-naphthol, and reducing by means of zinc dust and acetic acid in hot ethanol solution gave N-phenyl-N'-1 -(2-naphthol)-hydrazine, which obtained by this means were uns- table when exposed to air at room temperature. 4-(4-amino-phenyl)-2-hydroxy-1-naphthylamine hydrochloride ( diamine Ⅰ) is formed by phenyl-hydrazo-2-naphthol with the acid rearrangement by treatment of the hydroazo compound with hydroc- hloric acid at 0℃. yield 41.9%. mp>300 0℃. Analogously, o-Toluidine yielded-4-amino-phenyl) -2-hydroxy-1- naphthol amine hydrochloride(Ⅱ), mp>300 0℃. in37.5 %. o- Anisidine yielded 4-(ortho-anisyl-4-amino-phenyl)-2-hydroxy- 1-naphthyl amine hydrochloride(Ⅲ), mp>300 0℃, in 35.6%. 1-amino-8-naphthol-3,6-disulfonic acid (H-acid) orβ-naphthol or 6-amino-1-naphthol-3-sulfonic acid (J-acid) or 7-amino- napht- hol or 6-amino-1-naphthol-3-sulfonic acid (r-acid) was coupled with those diamine diazonium slats in low temperature and strong basic sloution,to give dyes.The maximum absorption were between 530-641 nm. Successfully synthesized the unsymmetric benzidine type of phenyl-naphthol diamine derivatives and their diazo dyes.
Rajakumari, P. Maria Nirmal. "Network Formation In Amine Curing Of Higher Functional Epoxy Resins." Thesis, 1996. http://etd.iisc.ernet.in/handle/2005/1872.
Full textHui, Hsin-Yi, and 許欣怡. "The effect of cubic SiC on formation of oriented diamonds on Si(100) substrates." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/57031210340225400820.
Full text國立交通大學
材料科學與工程系所
95
This dissertation focuses on the study of formation of cubic SiC (β-SiC) and oriented diamond film by microwave plasma chemical vapor deposition (MPCVD). In the first part of the dissertation, the main focus is on formation of β-SiC buffer layer using various deposition parameters including precursors, microwave power, and bias time. In the second part, the fabricated β-SiC was used as the substrate for the study of growth of oriented diamonds. Before SiC growth, carburization MPCVD had been performed using propane and methane as carbon sources. The <100> β-SiC layers on Si(100) substrates were synthesized by MPCVD using a mixture of propane and hydrogen gases as precursors with the application of a negative bias on the specimen. The morphology, crystallinity and chemical bonding after β-SiC formation on Si substrates were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). It is found that the microwave power and the bias time have great influence on the formation of α-SiC and β-SiC phases, their sizes and the density. The β-SiC islands exhibit a stripe morphology with width and length of 0.2μm and 0.1μm, respectively. In the diamond thin film growth process, only methane in hydrogen was used as reacted gases. Temperature and methane concentration are the major factors affecting oriented diamond growth based on the results of SEM, XRD, and Raman spectroscopy. It is demonstrated that <100>textured β-SiC in the first process can be used to fabricate high-quality diamond films with the <100>texture in which the epitaxial ratio approaches 38% for one hour growth under proper deposition conditions of 1% CH4 and growth temperature at 700℃.