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 27 for “"nitrogen atmosphere"”.
-
The fabrication of silicon carbide heating elements
… heat treatment, because of the influence of the nitrogen atmosphere in the furnace. The fabrication parameters important in the manufacture of heating elements were investigated. Porous sintered silicon carbide samples were made using different proportions of grit sizes and various firing …
-
A Study of the Volatile Matter of Coal as a Function of the Heating Rate
… TGA system. All measurements were made in a nitrogen atmosphere. The results of the study illustrate the dependance of the volatile matter yield on the heating rate. For most coals and cokes the optimum heating rate for determining volatile matter values that agree with those obtained by ASTM …
-
Processing and properties of silicon nitride ceramics
… powder. The silicon was reaction bonded in nitrogen atmosphere to form reaction bonded Si₃N₄,which was then sintered between 1700°C and 1800°C to form a dense Si₃N₄ ceramic. The silicon nitride powder compacts were also sintered between 1700°C and 1800°C. In order to achieve densification …
-
An investigation of the chemistry of lithiotriphenylphosphineacetylmethylene
… n-butyllithium in tetrahydrofuran-hexane under a nitrogen atmosphere at -78º. This ylide anion reacted selectively with alkyl halides to form γ-substituted 13-keto phosphonium ylides. Subsequent ionization of triphenylphosphine-(3-phenylpropionyl)methylene with n-butyllithium at -78° followed by …
-
ΠΥΡΟΛΥΣΗ ΕΛΛΗΝΙΚΟΥ ΛΙΓΝΙΤΗ
… LIGNITE PYROLYSIS IN A FLUID BED REACTOR AND IN NITROGEN ATMOSPHERE. THE EXPERIMENTAL SYSTEM HAS SOME ADVANTAGES: HIGH HEATING RATES,REAL ISOTHERMAL CONDITIONS AND ON-LINE MEASUREMENTS OF TOTAL GASES AND HYDROCARBONS PRODUCED DURING PYROLYSIS. IN THIS WORK THE INFLUENCE OF FIVE VARIABLES ON THE …
-
A photographic investigation of the collision, reaction, and ignition of hypergol droplets
… droplet and an oxidizer droplet to collide in a nitrogen atmosphere at temperatures from 50°C to 430°C. The resulting phenomena were photographed with a 16mm Fastax camera. Experimentation was completed in three series of tests. The first series consisted of impacting hydrazine droplets with …
-
Development of teawaste based bio-sorbent materials for removal of Cr(VI) from wastewater
… at 600℃ for 6 hours in a tubular furnace under nitrogen atmosphere. Finally, the modified teawaste was produced, magnetic bleached teawaste bio-sorbent (MBTW). The effects of initial concentration, amount of adsorbent, adsorption time and adsorption temperature on the adsorption of hexavalent …
-
Phase separation spinning of porous polypropylene hollow fibers
… mixing vessel and stirrer, the use of a nitrogen atmosphere, and the addition of proper stabilizers, this problem should be prevented in future studies. From observations made by optical and scanning electron microscopes, and mercury intrusion pore size distribution measurements, it was …
-
Kinetic studies of solid-phase polycondensation in two polyamides and a polyester
… 120 to 180 °C for periods of 5 to 20 hours in a nitrogen atmosphere. A similar procedure was followed with the polyester except that the range of temperature was 160 to 200 °C. The number-average molecular weights of the polymers before and after treatment were calculated from the polymer …
-
Comparison of Nitronic 50 and Stainless Steel 316 for use in Supercritical Water Environments
… tests under conditions ranging from an inert nitrogen atmosphere, to both subcritical and supercritical water, with the failed samples surface characterized by optical microscopy, scanning electron microscopy, and Raman spectroscopy. Electrochemical studies were performed via potentiodynamic …
-
Novel approaches to engineer glucose biosensors
… persulphate and sodium metabisulfite under a nitrogen atmosphere. The hydrogel was applied to the sensor by dip coating during polymerisation. Electrochemical measurements revealed that the response characteristics of sensors coated with this membrane are highly consistent. Scanning …
-
Production of biodegradable poly lactic acid from pineapple industry wastewater by lactobacillus casei fermentation
… conditions (temperature, pH, inoculum size, nitrogen source) for lactic acid (LA) production was carried out. Purification of LA by reverse osmosis was done. After that, synthesize of PLA was achieved by direct polymerization of pure LA under a nitrogen atmosphere at an optimum time and …
-
Advances In The Electrodeposition Of Tantalum From Ionic Liquids In A Technical Plating Setup
… into a glove box containing an ultra-high purity nitrogen atmosphere. The actual plating process was conducted galvanostatically, and the applied current and electrolyte composition were varied to determine the effect on the deposition process. Electrodeposits formed during experimental trials …
-
Precipitation, Aggregation, and Settling of Asphaltenes from n-Alkane Diluted Bitumens
… amount of precipitation were measured in air and nitrogen. The size distribution, fractal dimension, and settling rates of the aggregates were also measured. Asphaltene aggregates were found to be fused fractal structures that are insensitive to shear once formed. A semi-empirical correlation for …
-
Isolation and lactose metabolism of Streptococcus lactis variety tardus from southwestern Virginia
… Under shake-culture conditions with a nitrogen atmosphere (anaerobic) the pattern of fermentation products changed so that 60 per cent of the total acid produced was lactic, about 20 per cent was formic and 10 to 15 per cent, acetic acid. Under aerobic shake-culture conditions the acid …
-
Comparative Study of the Effects of Physical and Chemical Aging on Extracted and Recovered Asphalt Binders from Some Municipal and Provincial Roads in Canada
… rotary evaporation in a moderate to high vacuum, nitrogen atmosphere and final bath temperature of 160 °C for one hour. The binders recovered from the loose-mix samples were taken through laboratory aging using the standard Superpave® pressure aging vessel method and all the samples were evaluated …
-
Raman microscopy studies of carbon particles from diesel particulate matter (DPM) and coal dust
… heat-treating the specimens to 625°C in an inert nitrogen atmosphere, before the Raman analysis. The resultant PLS model, after heat-treatment, dramatically improved the R2 values such that the DPM and coal dust were 0.974 and 0.907, respectively. This model was used to predict the composition of …
-
Interfacial Electrochemistry and Surface Characterization: Hydrogen Terminated Silicon, Electrolessly Deposited Palladium & Platinum on Pyrolyzed Photoresist Films and Electrodeposited Copper on Iridium
… This includes dissolved oxygen poor media after nitrogen bubbling and equilibration under nitrogen atmosphere, as well as metal contaminated solutions. Both microscopically rough and ideal monohydride terminated surfaces are examined. Hydrogen terminated silicon is also used as the sensing …
-
Electrodeposition of Nb, Ta, Zr and Cu from Ionic Liquid for Nanocomposites Preparation
… at different temperatures in a glove box, under nitrogen atmosphere. Galvanostatic runs and cyclic voltammograms performed at different scan rates and different potential windows have been carried out in order to determine the behaviour of the systems employed. Potentiostatic experiments were …
-
Rotational Molding of Acrylonitrile-Butadiene-Styrene Polymers and Blends
… of the resin, drying of the resin, internal mold atmosphere, and oven temperature. It was found that using coarse particle sizes (ground at 20-mesh rather than the industry standard of 35-mesh) increased the impact strength by about 19%. None of the other parameters proved to have a significant …
Page 1 of 2