Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 40 for “"inert atmosphere"”.
-
The esterification of tall oil to obtain drying oil characteristics
… tall oil. Refined tall oil was esterified in an inert atmosphere with pentaerythritol at temperatures of 250, 300, and 320°C. Carbon dioxide was used to maintain an inert atmosphere. The esterification was carried out in a glass, Wolfe, three-necked flash heated in a constant temperature oil bath …
-
Part One: Catalytic Reactions of Anion-Exchange Resin Bound Dodecarhodium Triacontacarbonyl Dianion and Its Derivatives and Part Two: Properties and Reactions of Neutral Non-Polar Solvent Soluble Binuclear Complexes
… of the cluster at room temperature under an inert atmosphere leads to intact Rh(,12) (CO)(,30)('2-) being bound. This material exhibits only limited activity for the hydroformylation of of 1-hexene, accompanied by extensive isomerization of the substrate to 2-hexene, at 100 C and 8 atm of …
-
Optimisation of hydroxyapatite (HAp) for orthopaedic application via the chemical precipitation technique
… synthesis under a controlled environment (inert atmosphere) is desirable in order to achieve a high level of crystallinity: with an increase from 86.32% synthesised at 20ºC to 95.19% synthesised at 60ºC. The presence of an inert atmosphere appears less critical at synthesis under increased …
-
Reduction expansion synthesis for magnetic alloy powders
… heating to approximately 800 degrees Celsius, in inert atmosphere, of physical mixtures of urea, or similar molecules, and metal oxide, hydroxide or nitrates. As shown by scanning electron microscopy and x-ray diffraction, RES produced submicron magnetic particles. Essential to both 3D printing …
-
Thermochemical conversion of high-density polyethylene (HDPE) to value-added products using cobalt-based catalysts
… method of treating plastic thermally under an inert atmosphere to convert HDPE into valuable products, such as wax, oil, gas, and char. The current thesis explores the utilization of cobalt-based catalysts in the HDPE pyrolysis. The study investigates the effects of cobalt loadings in …
-
Synthesis and Characterization of Biobased Carbon Nanoparticles from Lignin
… after the sublimation process in oxidizing atmosphere followed by the carbonization process in an inert atmosphere at 700oC using tubular furnace. The increase in glass transition tem-perature during thermo-stabilization process was confirmed by DSC analysis. The con-densation reactions …
-
An investigation into tool-wear and phenomena influencing tool-life in milling
… special tests have been conducted within an inert atmosphere to ascertain the influence of oxidation on wear rate. It is also found that the influence of exit conditions may be critical in some circumstances, and experiments have again been carried out to examine this phenomenon. Finally, …
-
Sigma phase in the ternary systems chromium-cobalt-copper and chromium-manganese-copper
… Cr-Co~Cu alloys and annealing these alloys in an inert atmosphere of a helium-hydrogen gas mixture. The Cr-Mn-Cu alloys were melted under a helium atmosphere and annealed in evacuated Vycor tubes. By the use of metallographic techniques and x-ray analysis the phases present in each alloy were …
-
Sol-gel deposition of oxide-ion conducting thin films ; and, Liquid precursors to hafnium and tantalum carbides
… materials. These precusors were pyrolyzed under inert atmosphere and found to convert to the metal carbide, plus excess carbon, between 1100 °C and 1500 °C. The use of Grignard reagents to functionalize (chloromethyl)silylterminated carbosilane dendrimers was investigated briefly. The syntheses …
-
Bruchmechanische Untersuchungen an Werkstoffen für Dampfkraftwerke mit Frischdampftemperaturen von 500 bis 650 C
… necessary to know the impact of different test atmospheres and temperatures on the crack growth rate. In the present work, the influence of atmosphere (air, vacuum, simulated live steam), proof-temperature, hold time, thermal exposure on the crack growth has been studied at temperatures between …
-
The dissolution of lime in iron silicate melts.
… melts. The experiments were carried out under an inert atmosphere of argon at 1300°C in a vertical tube furnace. A small cylindrical pellet of lime was preheated to the melt temperature before being immersed in the melt contained in an iron crucible. After a preselected period, ranging from 10 …
-
Processing and Properties of Particulate Reinforced Carbon Matrix Composites
… ramping back down to room temperature, all in an inert atmosphere. XRD was performed on heat treated samples before polishing, while optical microscopy and SEM were performed after mounting and polishing. TGA was performed on the milled powders, while hardness was performed on the heat treated …
-
The Sonochemistry of Some Metal Carbonyl Complexes (Iron, Chromium)
… with a sample cell equipped for cryogenic and inert atmosphere work. Sonication of the stable free radical diphenylpicryhydrazyl in a variety of solvents resulted in bleaching of its intense color, and demonstrated the ability of a wide range of organic solvents to support sonochemical …
-
Effect of base metal oxygen content and oxygen activity on mechanical properties of EN-GJL- GG - 26 Cu-Cr grey cast-iron heavy-duty crank cases
… a duration of 0 to 24 hours in a closed furnace/inert atmosphere, and how the addition of reactive iron oxide from 0 to 0.2wt% affects the oxygen content and activity at the different holding duration, and what will be its impact on the graphite morphology and the resulting mechanical properties. …
-
Studies on Hydrogen Selective Silica Membranes and the Catalytic Reforming of CH₄ with CO₂ in a Membrane Reactor
… of tetraethylorthosilicate (TEOS) in an inert atmosphere. These membranes displayed high hydrogen permeances (10⁻⁸ - 10⁷ mol m⁻² s⁻¹ Pa⁻¹) and excellent H₂ selectivities (above 99.9 %) over other gases (CH₄, CO, and CO₂). The membranes were characterized using Scanning Electron Microscopy …
-
Synthesis of Heteroleptic Redox-active and Spin-crossover Complexes
… diamagnetic. However, there is potential under inert atmosphere to produce Co2+ and possibly a phenoxyl radical species with redox-active valence tautomers.
-
Kinetics of propylene disproportionation over a tungsten oxide on silica catalyst
… 454° Centigrade and pressures from one to nine atmospheres were used. The experimental data were well correlated by assuming that a Langmuir-Hinshelwood, dual-site surface reaction was the rate controlling step in the reaction mechanism. The mechanism parameters and their temperature dependence …
-
"Reactive hard templating" : from carbon nitrides to metal nitrides
… temperatures between 600°C and 800°C even under inert atmosphere, g-C3N4 was shown to be a good nitrogen donor for the synthesis of early transition metal nitrides at high temperatures. Thus using the nanostructured carbon nitrides as “reactive templates” or “nanoreactors”, various metal nitride …
-
Synthesis and characterization of high Tg nanofoams based on pyromellitic dianhydride and 1,1-bis(4-aminophenyl)-1-phenyl-2,2,2-trifluoroethane polyimide block and graft copolymers
… could be obtained. Upon thermal treatment under inert atmosphere, the materials can be spun cast and cured in place, if so desired. However, if the polymers are exposed to the oxygen atmosphere, the unstable component can be selectively degraded, generating micropores that are related to the size …
-
High Grade Carbon From Crop Oil Tars
… purity carbon through pyrolysis of the tar in an inert atmosphere. Residual tars are converted into carbon, while simultaneously removing and recovering distillates to be recycled back through the system where they can be processed into other fuel and chemical products. </p> <p>The carbonization …
Page 1 of 2