Stratigraphic Relations Of Members Of The Needles Range Formation At Type Localities In Southwestern Utah

The Needles Range Formation is one of the most extensive of the middle Tertiary ash-flow sheets in the Great Basin of Nevada and western Utah. The original definition of the formation by Mackin (1960) named two members and mentioned three type localities. Our recent studies have shown that this published information now requires revision. To provide a firm basis for stratigraphic studies of the Needles Range Formation, this paper presents geologic maps, measured sections, and paleomagnetic data for three type localities in southwestern Utah. These include the northern Needles Range and Wah Wah Springs localities previously mentioned by Mackin, plus a new locality, northwest of Lund, Utah. The sequence of members at these localities, from oldest to youngest, is: Cottonwood Wash Tuff (new name), Wah Wah Springs Turf, Lund Tuff (new name), and Wallaces Peak Tuff (new name). We recommend abandonment of the name Minersville Tuff. © 1973 Geological Society of America

Deuteron Detection Efficiency of Ge Telescopes

This research was sponsored by the National Science Foundation Grant NSF PHy 87-1440

Lost circulation in geothermal wells: research and development status

A multifaceted program directed at understanding and helping to solve the lost circulation problem is described. The program involves characterizing loss zones, developing an analytic fluid-dynamics model of zone plugging, screening lost circulation materials in the laboratory and testing some solutions in a large-scale test facility. The status and plans for this program are presented

Narrow 0\u3csup\u3e+\u3c/sup\u3e state in \u3csup\u3e20\u3c/sup\u3eNe and 0\u3csub\u3e6\u3c/sub\u3e\u3csup\u3e+\u3c/sup\u3e and 0\u3csub\u3e7\u3c/sub\u3e\u3csup\u3e+\u3c/sup\u3e rotational bands

A reanalysis of old data removes the (0+,2+) ambiguity for a very narrow state at Ex(20Ne)=11.55 MeV and gives a unique 0+ assignment. Such a 0+ state corresponds well to a predicted state at 11.494 MeV of unusually small reduced widths for decay to both the ground and first excited state of 16O. This new 0+ state is a better 06+ band head for the 8p-4h states at 15.159 MeV (6+) and 18.538 MeV (8+) than the currently accepted 0+ state at 12.44 MeV. Possible 2+ and 4+ members are considered. The higher 0+ level at Ex=12.44 starts a new 07+ band, and candidates for this band are critically discussed

High-Temperature Organic Rankine Cycle Utilizing Novel Scroll Expander and Pump

Organic Rankine Cycles (ORC) are widely employed to extracting work from different heat sources to improve the operational efficiency of thermal systems. High-temperature ORCs (\u3e 250 – 300 °C) are still particularly challenging especially when hydrocarbons cannot be used as the working fluids. Generators for Small Electric and Thermal Systems (GENSETs) are one example of systems where ORCs can be used as a bottoming cycle. A 1 kWe ORC has been previously constructed to evaluate the feasibility of designing an ORC with a heat source inlet temperature of approximately 500 °C. The test stand utilizes microtube evaporator, an air-cooled microchannel condenser, a plate heat exchanger as regenerator, scroll rotating machines as both expander and pump. To increase the efficiency of the ORC, novel scroll pump design and Oldham Ring scroll expander were installed. An extensive experimental campaign was carried out to map the performance of the expander and the pump along with the overall system performance using R245fa as the working fluid. In addition, thermocouple mesh has been inserted at the upstream and downstream of the evaporator to study the temperature maldistribution from the heat source. The performance was mapped at steady state over a range of operating conditions. The mapped performance has been used to develop a charge-sensitive dynamic model of the ORC system to be predict performance at off-design conditions and develop a control strategy. A discussion on the degradation of the lubricant oil in the system has also been included

Orientation dependency of mechanical properties of 1950`s vintage Type 304 stainless steel weldment components before and after low temperature neutron irradiation

Databases of mechanical properties for both the piping and reactor vessels at the Savannah River Site (SRS) were developed from weldment components (base, weld, and weld heat-affected-zone (HAZ)) of archival piping specimens in the unirradiated and irradiated conditions. Tensile, Charpy V-notch (CVN), and Compact Tension C(T) specimens were tested at 25 and 125C before and after irradiation at low temperatures (90 to 150C) to levels of 0.065 to 2.1 dpa. irradiation hardened the weldment components and reduced the absorbed energy and toughness properties from the unirradiated values. A marked difference in the Charpy V-notch absorbed energy and the elastic-plastic fracture toughness (J{sub IC}) was observed for both the base and HAZ components with the C-L orientation being lower in toughness than the L-C orientation in both the unirradiated and irradiated conditions. Fracture surface examination of the base and HAZ components of unirradiated C(T) specimens showed a ``channel`` morphology in the fracture surfaces of the C-L specimens, whereas equiaxed ductile rupture occurred in the L-C specimens. Chromium carbide precipitation in the HAZ component reduced the fracture toughness of the C-L and L-C specimens compared to the respective base component C-L and L-C specimens. Optical metallography of the piping materials showed stringers of second phase particles parallel to the rolling direction along with a banding or modulation in the microchemistry perpendicular to the pipe axis or rolling direction of the plate material