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The Effect of Oxygen in Coal

Description: From Introduction: "This paper is the result of a comparative study of ultimate coal analyses made and published by the United States Geological Survey. The initial comparisons, made from a relatively small number of analyses, not only confirmed a previous conviction that the elimination of oxygen incident to the development of a coal is economically far more important than has been generally suspected, but also showed that oxygen is very nearly as harmful as ash in coal."
Date: 1911
Creator: White, David
Partner: UNT Libraries Government Documents Department

Method of Testing Oxygen Regulators

Description: Oxygen regulators are used in aircraft to regulate automatically the flow of oxygen to the pilot from a cylinder at pressures ranging up to 150 atmospheres. The instruments are adjusted to open at an altitude of about 15,000 ft. and thereafter to deliver oxygen at a rate which increases with the altitude. The instruments are tested to determine the rate of flow of oxygen delivered at various altitudes and to detect any mechanical defects which may exist.
Date: June 1935
Creator: Sontag, Harcourt & Borlik, E. L.
Partner: UNT Libraries Government Documents Department

Effect of inlet oxygen concentration on combustion efficiency of J33 single combustor operating with gaseous propane

Description: Report presenting an investigation to determine the effect of oxygen concentration of the inlet oxygen-nitrogen mixture on the combustion efficiency of a J33 single combustor operating with gaseous propane fuel. Combustion efficiency data were obtained at a variety of combustion-inlet total pressures, fuel flow rates, and inlet oxygen concentrations. Results regarding combustor data, application of fundamental combustion properties to combustor data, application of simplified reaction kinetics equation to combustor data, comparison of liquid and gaseous fuel data, and limitations of correlation parameters.
Date: March 31, 1953
Creator: Graves, Charles C.
Partner: UNT Libraries Government Documents Department

Oxygen boosting of an aircraft-engine cylinder in conjunction with internal coolants

Description: Report presenting an investigation to determine the possibility of attaining or approaching critical-altitude power at altitudes considerably higher than the critical as limited by the supercharger by the use of oxygen in conjunction with internal coolants.
Date: April 1944
Creator: Spencer, Robert C.; Jones, Anthony W. & Pfender, John F.
Partner: UNT Libraries Government Documents Department

Tests of artificial flight at high altitudes

Description: From Report: "If we wish to form an accurate idea of the extraordinary progress achieved in aeronautics, a comparison must be made of the latest altitude records and the figures regarded as highest attainable limit some ten years ago. It is desirable, for two reasons, that we should be able to define the limit of the altitudes that can be reached without artificial aid. First, to know to what extent the human body can endure the inhalation of rarified air. Second, the mental capacity of the aviator must be tested at high altitudes and the limit known below which he is able to make reliable observations without being artificially supplied with oxygen. A pneumatic chamber was used for the most accurate observations."
Date: November 1920
Creator: Gradenwitz, Arthur
Partner: UNT Libraries Government Documents Department

Genetic and Environmental Factors that Mediate Survival of Prolonged Oxygen Deprivation in the Nematode Caenorhabditis Elegans

Description: Ischemic events of even a very short duration are not tolerated Ill in humans. The human cost of ischemia, when looked at as combined cardiovascular disease, dwarfs all other causes of death in the United States. Annually, CVD kills as many people in the US as does cancer, chronic lower respiratory disease, accidents, and diabetes mellitus combined. In 2005 (the latest year for which final statistics are available), CVD was responsible for 864,480 deaths or 35.3 percent of total deaths for the year. In my study, I have used the nematode Caenorhabditis elegans to determine genetic and environmental modulators of oxygen deprivation a key component of ischemia. I have found that animals with mutations in insulin like signaling pathways, neuronal function, electron transport chain components, germline function, and animals that are preconditioned by being raised on a diet of E. coli HT115 bacteria at 25°C have an enhanced ability to survive long-term (>72 hours) anoxia (<.005 kPa O2) at 20°C. The enhanced anoxia survival phenotype partially correlates with increased levels of carbohydrate stores in the nematodes. Suppression of this enhanced anoxia survival phenotype is possible by altering expression of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase, the FOXO transcription factor DAF-16, and 5’-AMP kinase.
Date: August 2010
Creator: LaRue, Bobby Lee, Jr.
Partner: UNT Libraries

Kinetics of the Reactions of Carbon Dioxide and Steam with Coke

Description: From Summary: "To incorporate the role of diffusional resistance in the rate equations it is essential that the solid state of the carbons be better understood; that is, their microporosity, crystallinity, and electronic state of free and oxygen-containing reaction sites. The importance of the solid state to kinetic behavior has been stressed throughout the text."
Date: 1962
Creator: Ergun, Sabri
Partner: UNT Libraries Government Documents Department

Hypoxia and the Development of Endothermic Capacity in Chickens (Gallus Gallus)

Description: Adult chickens employ endothermy – internal generation of heat that maintains a constant body temperature (Tb). Prior to hatching, chicken embryos are ectothermic - controlling Tb by external heat sources. Upon hatching, the hatchling transitions from an ectotherm to an endotherm that has been shown to be delayed by hypoxia. In this study, whole animal oxygen consumption () and liver, heart, and skeletal muscle citrate synthase activity (CSA) and were measured during this transition to endothermy in chickens incubated in normoxia and hypoxia (15% O2). The only significant differences in occurred in 48 hour old hatchlings where was lower in normoxic hatchlings. There were no differences in CS activity between age and incubation oxygen levels. Additionally, preliminary 2-D protein gels of embryo and hatchling liver show changes in the proteome upon hatching. Results suggest that hypoxia had no significant effect on CSA and a minimal effect on .
Date: August 2012
Creator: Neely, Aaron Mackallan
Partner: UNT Libraries

Adenosine and down-regulation of myocardial oxygen demand

Description: This investigation studied the physiological means by which myocardium can survive and function properly when oxygen supply is limited and cannot initially match oxygen demand. The effects of isoproterenol (ISO) stimulations during low coronary perfusion pressure or hypoxemia on myocardial oxygen demand, work, and oxygen utilization efficiency were investigated.
Date: December 1991
Creator: Lee, Shang Chiun
Partner: UNT Libraries

Determination of Oxygen in Sodium

Description: Abstract: "A method has been developed for the determination of sodium monoxide in sodium which depends upon the reaction between sodium and n-butyl bromide in hexane solution. The sodium monoxide does not react with the reagent and can be determined, after the addition of water, by titration. The method is comparatively rapid, requires only the simplest of equipment, and it has the advantage that both oxygen and other impurities can be determined on the same sample."
Date: April 30, 1952
Creator: White, J. C.; Ross, W. J. & Rowan, R.
Partner: UNT Libraries Government Documents Department

Effect of oxygen recombination on one-dimensional flow at high Mach numbers

Description: Report presenting a theoretical analysis of air flow in a channel in which oxygen dissociation and recombination occur. An investigation is also made of the comparative relaxation times of the oxygen dissociation-recombination reaction in relation to molecular vibrations.
Date: January 1958
Creator: Heims, Steve P.
Partner: UNT Libraries Government Documents Department

Aeronautic Instruments Section 6: Oxygen Instruments

Description: This report contains statements as to amount of oxygen required at different altitudes and the methods of storing oxygen. The two types of control apparatus - the compressed oxygen type and the liquid oxygen type - are described. Ten different instruments of the compressed type are described, as well as the foreign instruments of the liquid types. The performance and specifications and the results of laboratory tests on all representative types conclude this report.
Date: 1923?~
Creator: Hunt, F. L.
Partner: UNT Libraries Government Documents Department

Discovery of Critical Oxygen Content for Glass Formation in Zr80Pt20 Melt Spun Ribbons

Description: Zr{sub 80}Pt{sub 20} alloys may form meta-stable quasicrystals either during devitrification of an amorphous phase or directly upon cooling from a liquid depending on processing conditions. To date, little attention has been given to the role of oxygen on the glass formation or devitrification behavior of Zr-Pt and similar alloys. This study reveals that oxygen content during melt spinning indeed strongly influences the formation of the as-quenched structure. A critical amount of oxygen was found to be required to form amorphous ribbons at a fixed quench rate. At lower oxygen levels (i.e., &lt;500 ppm mass), a fully crystallized is formed; the structure is composed mainly of meta-stable {beta}-Zr with a small fraction of a quasicrystalline phase. At higher oxygen levels, the as-quenched structure transitions to a fully amorphous structure ({approx}1000 ppm mass), and with further oxygen addition forms a mixture of amorphous and quasicrystalline ({approx}1500 ppm mass) or crystalline phases (&gt;2500 ppm mass). Details regarding the structure of the meta-stable {beta}-Zr phase in the low-oxygen ribbons are provided along with a discussion of the structural similarity between this phase and the quasicrystal structure that formed in this alloy.
Date: September 30, 2004
Creator: Sordelet, D.J.; Rozhkova, E.A.; Yang, X. & Kramer, M.J.
Partner: UNT Libraries Government Documents Department

Parallel expression evolution of oxidative stress-related genes in fiber from wild and domesticated diploid and polyploid cotton (Gossypium)

Description: This article studies the evolution of oxidative stress related genes in a single plant cell by conducting comparative expression profiling analyses of the elongated seed trichomes of cotton, using a phylogenetic approach.
Date: August 17, 2009
Creator: Chaudhary, Bhupendra; Hovav, Ran; Flagel, Lex; Mittler, Ron & Wendel, Jonathan F.
Partner: UNT College of Arts and Sciences

The Quality of Surface Waters in Texas

Description: Abstract: The discharge-weighted average concentrations of dissolved solids, chloride, and sulfate for many of the principal streams in Texas are less than 500 mg/1 (milligrams per liter), 250 mg/1, and·250 mg/1, respectively. At 65 of 131 sites on streams that were sampled at least 10 times, the biochemical oxygen demand of at· least half the samples exceeded 3,0 mg/1. At 20 of the sites, the dissolved-oxygen content of at least !half the samples was less than 5.0_ mg/1. The higher concentrations of minor elements usually were detected in waters from urban areas, indicating a relation to man's activities. Small amounts of some pesticides are widely distributed in low concentrations. The higher concentrations usually were detected in waters from urban areas. Small amounts of some of the pesticides studied are widely distributed in surface waters in Texas. Some of the more widely distributed pesticides were 2,4,5-T at 96 sites, diazinon at 80 sites, 2,4-D at 78 sites, dieldrin at 77 sites, Silvex at 47 sites, DDT at 67 sites, lindane at 59 sites, DDD at 51 sites, DDE at SO sites, and chlordane at 38 sites.
Date: July 1974
Creator: Rawson, Jack
Partner: UNT Libraries Government Documents Department

Immunohistochemistry of the Gills of the Channel Catfish Ictalurus Punctatus: Cells and Neurochemicals That May Be Involved in the Control of Cardioventilatory Reflexes

Description: In teleost fishes the neurochemicals involved in sensing and responding to hypoxia are unresolved. Serotonergic branchial neuroepithelial cells (NECs) are putative O2 chemoreceptors believed to be homologous to the neural crest (NC) derived APUD (amine-precursor uptake and decarboxylation) pulmonary NECs and carotid body type-1 glomus cells. Branchial NECs contain serotonin (5-HT), thought to be central to the induction of the hypoxic cardioventilatory reflexes. However, application of 5-HT in vivo does not elicit cardioventilatory reflexes similar to those elicited by hypoxia. But previous in vitro neural recordings from glossopharyngeal (IX) afferents innervating O2 chemoreceptors in the trout gill show the same discharge response to hypoxic conditions as does that of acetylcholine (ACh) application. This evidence strongly supports the cholinergic hypothesis of chemoreceptor impulse origin rather than a serotonergic-induced impulse origin model. We therefore hypothesized that NECs contain ACh among other neurochemicals in cells belonging to the APUD series. Although serotonergic branchial NECs did not colocalize with ACh using immunohistochemical methods, several populations of ACh and/or tyrosine hydroxylase (TH) (catecholaminergic) positive, dopamine (DA) negative, cells were found throughout the second gill arch of the channel catfish Ictalurus punctatus. In addition, the NC derivation marker zn-12 labelled the HNK-1-like epitope (Human natural killer) expressed by lamellar pillar cells’ collagen column-associated pillar cell adhesion molecules (CC-PCAMs), evidence confirming their hypothesized NC origin.
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Date: December 2013
Creator: Oden, David S.
Partner: UNT Libraries