Search Results

Effects of X-Irradiation of Respiration in Frog Brain Tissue Slices Using the Oxygen Electrode Method

Description: The effects of X-irradiation at dosages of 40 r, 80 r, 160 r, 240 r, 320 r, 400 r, 800 r, 4 Kr, 8 Kr, and 16 Kr on the oxygen uptake of frog brain (Rana pipiens) tissue slices were studied. A membrane-covered oxygen electrode method was used to measure the respiratory rate. Continuous recordings were made before, during, and following X-irradiation in all of the test experiments. X-irradiation was delivered from a G. E. beryllium window X-ray unit at 120 KVP, 5 ma with a 1/4 mm Al filter.
Date: August 1971
Creator: Lin, Chen-hsiung
Partner: UNT Libraries

Integrated Assessment of Hypoxia in the Northern Gulf of Mexico

Description: This document details the ecological and economic effects of low oxygen (hypoxic) conditions in the Gulf of Mexico. This condition is caused by deforestation, river channelization, and the overuse of nitrogen in agricultural fertilizer. This document summarizes scientific evidence for the causes of hypoxia, the negative impact on Gulf of Mexico fisheries, and long-term national strategies for managing and mitigating the problem.
Date: May 2000
Creator: National Science and Technology Council (U.S.). Committee on Environment and Natural Resources.
Partner: UNT Libraries

Effects of O2, Ar, and H2 gases on the field-emission properties of single-walled and multiwalled carbon nanotubes

Description: In this article, the authors compare the effects of O2, Ar, and H2 gases on the field-emission (FE) properties of single-walled carbon nanotubes (SWNTs) and multiwalled carbon nanotubes (MWNTs).
Date: September 17, 2001
Creator: Wadhawan, Atul; Stallcup, Richard E.; Stephens, Kenneth F.; Pérez, José M. & Akwani, Ikerionwu A.
Partner: UNT College of Arts and Sciences

The role of prostaglandins, nitric oxide and oxygen in the ductus arteriosi of the pre-term chicken embryo (Gallus domesticus).

Description: The chicken ductus arteriosi (DA) are two embryonic blood vessels that shunt blood away from the non-ventilated lungs and towards the body and chorioallantoic membrane. I show that prostaglandins have a diminished role in maintaining chicken DA patency and nitric oxide inhibits oxygen induced contraction of the day 19 proximal DA in a time dependent manner. The pathways governing oxygen induced contraction in the chicken DA are similar to those found in mammals and include contributions from ROS, Kv channels, L-type Ca2+ channels, and the Rho kinase pathway. Longer exposure to high oxygen generates increased oxygen induced constriction of the day 19 DA that may be mediated through the Rho kinase pathway.
Date: December 2007
Creator: Greyner, Henry José
Partner: UNT Libraries

Kinetic and Thermochemical Studies of the Recombination Reaction Na + O₂ + N₂ from 590 to 1515 K by a Modified High-Temperature Photochemistry Technique

Description: Article on kinetic and thermochemical studies of the recombination reaction sodium + oxygen + nitrogen from 590 to 1515 K by a modified high-temperature photochemistry technique.
Date: September 1, 1989
Creator: Marshall, Paul & Narayan, A. S.
Partner: UNT College of Arts and Sciences

Chronic Hypoxia and Hyperoxia Modifies Morphology and Vegf Expression of the Lungs of the Developing Chicken (Gallus Gallus Domesticus)

Description: This study determines effects of oxygen levels on morphology and VEGF expression of developing chicken lungs following incubation in normoxia (21% O2), hypoxia (15% O2) or hyperoxia (30% O2), until developmental days 16 or 18. Lung morphology was assessed using light microscopy, while VEGF expression was determined with ELISA. In hypoxia, the proportion of parabronchial tissue and parabronchi including lumina increased from day 16 to 18 (61 to 68% and 74.2 to 82.2%, respectively). Non-parabronchial tissue was higher in hypoxia than in hyperoxia on day 16 (26 to 20%). However, by day 18, there were no differences between groups. VEGF expression was 33% higher in hypoxia than in hyperoxia on day 16 (736 vs. 492 pg/ml). On day 18, VEGF expression was 43% higher in hyperoxia than in normoxia (673 to 381pg/ml), and remained elevated by 40% in hypoxia over normoxia (631 pg/ml). VEGF may be a mechanism by which parabronchial tissue is stimulated from day 16 to 18 following exposure to chronic hypoxia.
Date: December 2012
Creator: Lewallen, Melissa Anjanette
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

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