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The origin of corundum associated with dunite in Western North CarolinaCobb, Margaret Cameron, January 1924 (has links)
Thesis--Bryn Mawr College, 1922. / Vita. Bibliography: p. 32-43.
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Basic magnesian rocks associated with the corundum deposits of Georgia ...King, Francis Plaisted, January 1906 (has links)
Thesis (Ph. D.)--Johns Hopkins University, 1897. / Life.
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Flame structure effects on the deposition of α-alumina via combustion CVDKelekanjeri, Siva Kumar 12 1900 (has links)
No description available.
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Změny některých fyzikálních vlastností vodné suspenze korundového prášku v průběhu ultrajemného mletí / Changes in some physical properties of the aqueous suspension of corundum powder during ultrafine grindingŠuleková, Nikola January 2018 (has links)
This thesis is focused on the study of changes in properties of the aqueous suspensions of corundum during ultrafine grinding without and with the addition of grinding activator. Such studies are an important step in optimizing the grinding process properly, because by measuring physical properties of a particulate substance, it is easy to determine the actual fineness of the ground substance and its quality for further processing. For the measurement of granulometry, zeta potential, rheological behavior and turbidity, corundum suspensions in distilled water were prepared in a 1:5 ratio without the addition of grinding activator and with the addition of triethanolamine (TEA), by using a planetary mill. The suspensions showed pseudoplastic behavior and the zeta potential of all samples ranged between -30 and 30 mV, thus the suspensions were rather unstable. During the grinding, the viscosity and turbidity of the samples increased. TEA was not proved to be a suitable activator for wet milling of corundum because of higher degree of fineness achieved during milling without an activator.
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The use of diffuse reflectance infrared spectroscopy in the study of aluminaCollins, Marc Kevin. January 1986 (has links)
Call number: LD2668 .T4 1986 C64 / Master of Science / Chemical Engineering
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Identification Methods of Sri Lankan Corundum in Comparison to Other Common Gemstones / Identifikationsmetoder av korund från Sri Lanka och jämförelse med andra vanligt förekommande ädelstenarKilbo Pehrson, Axel January 2017 (has links)
Sri Lanka is one of the leading countries in export of high quality corundum (Al2O3) gemstones due to the Precambrian rocks geological background. Combined highgrade metamorphic silicates and carbonate rocks makes perfect conditions for crystallization of this mineral. Weathered and eroded rocks have been transported by fluvial processes and formed gem gravels that are located throughout the country but mainly in the Highland complex of Sri Lanka. In order to determine whether a gemstone is corundum or any other gem mineral different techniques and instrumental methods are used. This report focuses on instrumental methods used to measure the minerals physical properties in order to get a definite mineral identification. Mineral identification in gemological circles is critical for determining the commercial value of a specimen. Factors like transparency and color of and inclusions in gemstone have to be taken into account when evaluating the value of a specimen. It also needs to be distinguished from artificial gemstones and heattreated specimens that in recent years have become more common due to more advanced techniques. By examine inclusions and the chemical composition of a rough or facetted specimen the origin and process can be determined. / Sri Lanka är ett av de ledande exportländerna av högkvalitativ ädelkorund (Al2O3) som bildats i landets prekambriska bakgrund. Hög metamorfos av silikat- och karbonatrika bergarter har skapat rätt miljö för mineralet att bildas. Vittrad berggrund har transporterats och avsatts av fluviala processer och ädelstensförande grus finns i huvudsakligen i Sri Lankas Highlandkomplex. För att kunna avgöra om en ädelsten är korund eller ett annat mineral används olika tekniker och instrument. Denna rapport fokuserar huvudsakligen på instrumentella metoder som mäter fysikaliska egenskaper hos mineral för att därigenom kunna få en definitiv mineralidentifikation. Inom gemologi är det absolut nödvändigt med mineralidentifikation för att bestämma det kommersiella värdet av en ädelsten. Även faktorer som transparens, färg och inneslutningar hos en ädelsten måste undersökas vid värdering. Syntetiska och eller värmebehandlade ädelstenar har blivit allt mer vanliga genom utvecklig av avancerad teknik och att skilja dessa från naturliga stenar är också viktigt. Genom undersökning av inneslutningar och den kemiska sammansättningen av en ädelsten kan dess ursprung och i vissa fall de geologiska bildningsprocesserna fastställas.
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Lead and arsenic speciation and bioaccessibility following sorption on oxide mineral surfacesBeak, Douglas Gerald, January 2005 (has links)
Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Includes bibliographical references (p. 152-160).
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Vztah pevnosti a charakteru povrchové úpravy keramických materiálů leptáním a žíháním / Relation strength to nature of surface improvement of ceramic materials by etching and annealingVladyka, Petr January 2008 (has links)
The goal of diploma thesis is study of the effect of thermal annealing at different temperatures and different annealing durations on the surface structure of oxide ceramics based on Al2O3 and study of the samples porosity.
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Kinetika vzniku ultrajemných částic meliva při expozici v dezintegračním systému. / Genesis of new ultra-fine particles of milling stock in the course of the mill exposure.Kejík, Pavel January 2012 (has links)
This work deals with the study of limestone and corundum dry milling using attritor-type stirred mill in a batch mode. There were stearin and polyethylene glycol used as surfactants and spherical shaped steel grinding elements used for the experimental part of the work. The main idea was to examine behavior of the selected grinding stock type within a long-term grinding forces exposure in selected conditions of ultrafine dry milling leading up to the submicron area. Characterization of samples was performed by laser granulometry, X-ray powder diffraction analysis, flame atomic absorption spectroscopy, objective color determination and electrokinetic potential measurement. Experimetaly measured data implies that in all cases there was a re-agglomeration of the grinding stock particles occurring, although in different stages of the disintegration process and in mutually various degree. The analysis results denote that a larger erosion of the crystal structures with the associated increase of the amorphous phase in the submicron particle size took place in the grinding stock.
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SNIC-DSM: SmartNIC based DSM Infrastructure for Heterogeneous-ISA MachinesRamesh, Hemanth 14 August 2023 (has links)
Heterogeneous computing is increasingly used in today's datacenters to meet the increasing computational demands of applications. Heterogeneous hardware typically includes CPUs, GPUs, ASICs, and FPGAs, among others. An important emerging trend is instructionset- architecture (ISA)-heterogeneity: high-end x86 servers with attached SmartNICs and SmartSSDs that incorporate general-purpose CPUs, typically of the RISC ISA family (e.g., ARM, RISC-V). To alleviate resource congestion on server computing nodes, application workloads can be scaled-out across server x86 CPUs and SmartNIC ARM CPUs using the distributed shared memory (DSM) abstraction. We present SNIC-DSM, a SmartNIC-based DSM infrastructure for heterogeneous ISA machines. SNIC-DSM implements a low-latency messaging layer, which enables inter-node communication across multi-ISA CPUs, and a DSM protocol processor that provides memory coherency among these nodes, both implemented in SmartNIC's FPGA logic. SNIC-DSM is reconfigurable and allows the implementation of different memory consistency protocols. Our experimental studies using compute-intensive benchmarks reveal that SNIC-DSM outperforms the state-of-the-art DSM - Popcorn Linux's software DSM - when server resource congestion is high. / Master of Science / The availability of heterogeneous computing architectures has led to the development of distributed shared memory systems, which allows compute-intensive applications to run in a distributed manner on different types of computing devices such as graphics processors, reconfigurable logic devices, and custom integrated circuits. Adopting such a heterogeneous computing strategy yields better performance and improves power consumption. Generally, these DSM systems use a software-based approach, which offers great flexibility but suffers from software overheads. Hardware-based approaches are used to overcome these limitations but they generally do not offer flexibility. This thesis presents, SNIC-DSM, which is a reconfigurable implementation of the DSM framework. SNIC-DSM provides a platform for the host and smart networking devices such as SmartNICs to communicate with each other and enables application execution in a distributed manner by providing memory coherency.
Our experimental evaluation using High-Performance Computing benchmarks reveals that SNIC-DSM improves performance when compared with software-based DSM.
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