3 resultados para DISSOCIATION ENERGIES
em Iowa Publications Online (IPO) - State Library, State of Iowa (Iowa), United States
Resumo:
This Executive Order expects the State government to envision an economic future for the State of Iowa in which its citizens will leak the nation toward the clean, safe, unlimited, efficient job producing prosperity-inducing and environmentally friendly energies of the 21st Century (sometimes referred to as a "Green Economy').
Resumo:
"Technical challenges exist with infrastructure that can be addressed by nondestructive evaluation (NDE) methods, such as detecting corrosion damage to reinforcing steel that anchor concrete bridge railings to bridge road decks. Moisture and chloride ions reach the anchors along the cold joint between the rails and deck, causing corrosion that weakens the anchors and ultimately the barriers. The Center for Nondestructive Evaluation at Iowa State University has experience in development of measurement techniques and new sensors using a variety of interrogating energies. This research evaluated feasibility of three technologies — x-ray radiation, ground-penetrating radar (GPR), and magnetic flux leakage (MFL) — for detection and quantification of corrosion of embedded reinforcing steel. Controlled samples containing pristine reinforcing steel with and without epoxy and reinforcing steel with 25 percent and 50 percent section reduction were embedded in concrete at 2.5 in. deep for laboratory evaluation. Two of the techniques, GPR and MFL, were used in a limited field test on the Iowa Highway 210 Bridge over Interstate 35 in Story County. The methods provide useful and complementary information. GPR provides a rapid approach to identify reinforcing steel that has anomalous responses. MFL provides similar detection responses but could be optimized to provide more quantitative correlation to actual condition. Full implementation could use either GPR or MFL methods to identify areas of concern, followed by radiography to give a visual image of the actual condition, providing the final guidance for maintenance actions." The full 103 page report and the 2 page Tech Transfer Summary are included in this link.
Resumo:
"Certainly no one person or state was the sole impetus for something as monumental as the Highway Research Board. Yet Iowa boasts of having provided many of the key people whose vision and energies literally created and sustained the HRB during its first critical years: Anson Marston, Thomas Agg, Thomas MacDonald, and Roy Crum." -- from page 2