52 research outputs found
Emissions data by category of engines
Exhaust gas pollutant emissions data under test stand conditions were obtained for the following: (1) full-rich baseline test (7-mode cycle), (2) lean-out tests for each power mode, and (3) different spark settings. The test data were also used to create a theoretical 5-mode cycle baseline. The emissions data in the framework of the theoretical 5-mode cycle were emphasized. There is no significant difference in the test results produced by data exhibited on the 7-mode cycle or 5-mode cycle. The 5-mode cycle was slightly more conservative for the carbon monoxide pollutant than the 7-mode cycle. The data were evaluated to determine which mode(s) had the greatest influence on improving general aviation piston engine emissions. Improvements that were achieved as a result of making lean-out adjustments to the fuel metering device were: (1) taxi mode only, (2) taxi and approach modes combined, and (3) leaning-out of the climb mode to best power
General aviation piston-engine exhaust emission reduction
To support the promulgation of aircraft regulations, two airports were examined, Van Nuys and Tamiami. It was determined that the carbon monoxide (CO) emissions from piston-engine aircraft have a significant influence on the CO levels in the ambient air in and around airports, where workers and travelers would be exposed. Emissions standards were set up for control of emissions from aircraft piston engines manufactured after December 31, 1979. The standards selected were based on a technologically feasible and economically reasonable control of carbon monoxide. It was concluded that substantial CO reductions could be realized if the range of typical fuel-air ratios could be narrowed. Thus, improvements in fuel management were determined as reasonable controls
'From bricks to clicks': Hybrid commercial spaces in the landscape of early literacy and learning
In their quest for resources to support children’s early literacy learning and development, parents encounter and traverse different spaces in which discourses and artifacts are produced and circulated. This paper uses conceptual tools from the field of geosemiotics to examine some commercial spaces designed for parents and children which foreground preschool learning and development. Drawing on data generated in a wider study I discuss some of the ways in which the material and virtual commercial spaces of a transnational shopping mall company and an educational toy company operate as sites of encounter between discourses and artifacts about children’s early learning and parents of preschoolers. I consider how companies connect with and ‘situate’ people as parents and customers, and then offer pathways designed for parents to follow as they attempt to meet their very young children’s learning and development needs. I argue that these pathways are both material and ideological, and that are increasingly tending to lead parents to the online commercial spaces of the world wide web. I show how companies are using the online environment and hybrid offline and online spaces and flows to reinforce an image of themselves as authoritative brokers of childhood resources for parents that is highly valuable in a policy climate which foregrounds lifelong learning and school readiness
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Extinguishing Fire with Carbon Dioxide in the Valier Mine, Valier Coal Company, Valier, Franklin County, Illinois
Report issued by the U.S. Bureau of Mines discussing mining fires, and the use of carbon dioxide as fire control. As stated in the introduction, "the purpose of this circular is to describe the sealing off of a mine fire and subsequent use of carbon dioxide gas to extinguish it" (p. 2). This report includes tables, and illustrations
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United States Bureau of Mines Technical Paper 727
Report issued by the Bureau of Mines discussing water pools that accumulate in Pennsylvania anthracite mines. Factors that lead to underground water pools, and methods for water drainage are presented. This report includes tables, maps, illustrations, and photographs
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United States Bureau of Mines Bulletin 4288
Report issued by the Bureau of Mines over the progress made on flood prevention in anthracite mines. As stated in the report, "the broad objective of the investigative work was to obtain factual data on: 1. anthracite reserves of Pennsylvania, 2. underground water pools, 3. barrier pillars, 4. the "buried valley" of the Susquehanna River, and 5. infiltration of surface water into underground mine workings" (p. 4). This report includes tables, graphs, maps, photographs, and illustrations
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