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Proceedings of Cryocooler Conference: 1984

Description: Abstract: This document contains the proceedings of the Third Cryocooler Conference, held at the National Bureau of Standards, Boulder, CO, on Sept. 17-18, 1984. About 140 people from 10 countries attended the conference and represented industry, government, and academia. A total of 26 papers were presented orally at the conference and all appear in written form in this document. The emphasis in this conference was on small cryocoolers in the temperature range of 4 - 80 K. Mechanical and non-mechanical types were discussed in the various papers. Applications of these small cryocoolers include the cooling of infrared detectors, cryopumps, small superconducting devices and magnets, and electronic devices.
Date: May 1985
Creator: Radebaugh, Ray; Louie, Beverly & McCarthy, Sandy E.
Partner: UNT Libraries Government Documents Department

Low-Temperature Carbonization Assay of Coal in a Precision Laboratory Apparatus

Description: From Summary: " A Low-Tempeature carbonization assay test is described, and factual data derived from this test are presented. The test procedure outlined in this report incorporates a mild-steel retort of improved design an accurately controlled method of heating, and a complete collection and condensation system for the solid, liquid, and gaseous products of carbonization."
Date: 1953
Creator: Goodman, John B.; Gomez, Manuel; Parry, V. F. & Landers, W. S.
Partner: UNT Libraries Government Documents Department

Beowawe Bottoming Binary Unit - Final Technical Report for EE0002856

Description: This binary plant is the first high-output refrigeration based waste heat recovery cycle in the industry. Its working fluid is environmentally friendly and as such, the permits that would be required with a butane based cycle are not necessary. The unit is modularized, meaning that the unit’s individual skids were assembled in another location and were shipped via truck to the plant site. This project proves the technical feasibility of using low temperature brine The development of the unit led to the realization of low temperature, high output, and environmentally friendly heat recovery systems through domestic research and engineering. The project generates additional renewable energy for Nevada, resulting in cleaner air and reduced carbon dioxide emissions. Royalty and tax payments to governmental agencies will increase, resulting in reduced financial pressure on local entities. The major components of the unit were sourced from American companies, resulting in increased economic activity throughout the country.
Date: February 12, 2013
Creator: McDonald, Dale Edward
Partner: UNT Libraries Government Documents Department

EXTENSION OF OPERATING LIFE OF KAPL-30 THIMBLE

Description: Due to extended low-temperature operation of the KAPL30 carbon steel thimble in the Materials Testing Reactor, a radiation damage evaluation was undertaken. Radiation damage in carbon steel may not be annealed under lowtemperature operating conditions. The data used in the evaluation are presented, and an extension of thimble life to 16 reactor cycles is recommended, subject to review if further low-temperature operation occurs. (D.E.B.)
Date: July 22, 1957
Creator: Lewis, D.M.
Partner: UNT Libraries Government Documents Department

Airfoil sampling of a pulsed Laval beam with tunable vacuum ultraviolet (VUV) synchrotron ionization quadrupole mass spectrometry: Application to low--temperature kinetics and product detection

Description: A new pulsed Laval nozzle apparatus with vacuum ultraviolet (VUV) synchrotron photoionization quadrupole mass spectrometry is constructed to study low-temperature radicalneutralchemical reactions of importance for modeling the atmosphere of Titan and the outer planets. A design for the sampling geometry of a pulsed Laval nozzle expansion has beendeveloped that operates successfully for the determination of rate coefficients by time-resolved mass spectrometry. The new concept employs airfoil sampling of the collimated expansion withexcellent sampling throughput. Time-resolved profiles of the high Mach number gas flow obtained by photoionization signals show that perturbation of the collimated expansion by theairfoil is negligible. The reaction of C2H with C2H2 is studied at 70 K as a proof-of-principle result for both low-temperature rate coefficient measurements and product identification basedon the photoionization spectrum of the reaction product versus VUV photon energy. This approach can be used to provide new insights into reaction mechanisms occurring at kinetic ratesclose to the collision-determined limit.
Date: October 12, 2011
Creator: Soorkia, Satchin; Liu, Chen-Lin; Savee, John D.; Ferrell, Sarah J.; Leone, Stephen R. & Wilson, Kevin R.
Partner: UNT Libraries Government Documents Department

Low-temperature charge transport in Ga-acceptor nanowires implanted by focused-ion beams

Description: Ga-acceptor nanowires were embedded in crystalline Si using focused-ion beams. The dc current-voltage characteristics of these wires after annealing are highly nonlinear at low temperatures, and a threshold voltage of less than 50 mV is observed independent of Ga+ dosage and implant beam overlap. These features suggest a Coulomb blockade transport mechanism presumably caused by a network of Ga precipitates in the substrate. This granular scenario is further supported by measurements of gated nanowires. Nanowires with metallic conductance at low temperatures could be achieved by reducing the current density of the focused-ion beams.
Date: July 31, 2007
Creator: Schenkel, Thomas; Robinson, S.J.; Perkins, C.L.; Tucker, J.R.; Schenkel, T.; Wang, X.W. et al.
Partner: UNT Libraries Government Documents Department

Macro-meso-microsystems integration in LTCC : LDRD report.

Description: Low Temperature Cofired Ceramic (LTCC) has proven to be an enabling medium for microsystem technologies, because of its desirable electrical, physical, and chemical properties coupled with its capability for rapid prototyping and scalable manufacturing of components. LTCC is viewed as an extension of hybrid microcircuits, and in that function it enables development, testing, and deployment of silicon microsystems. However, its versatility has allowed it to succeed as a microsystem medium in its own right, with applications in non-microelectronic meso-scale devices and in a range of sensor devices. Applications include silicon microfluidic ''chip-and-wire'' systems and fluid grid array (FGA)/microfluidic multichip modules using embedded channels in LTCC, and cofired electro-mechanical systems with moving parts. Both the microfluidic and mechanical system applications are enabled by sacrificial volume materials (SVM), which serve to create and maintain cavities and separation gaps during the lamination and cofiring process. SVMs consisting of thermally fugitive or partially inert materials are easily incorporated. Recognizing the premium on devices that are cofired rather than assembled, we report on functional-as-released and functional-as-fired moving parts. Additional applications for cofired transparent windows, some as small as an optical fiber, are also described. The applications described help pave the way for widespread application of LTCC to biomedical, control, analysis, characterization, and radio frequency (RF) functions for macro-meso-microsystems.
Date: March 1, 2007
Creator: De Smet, Dennis J.; Nordquist, Christopher Daniel; Turner, Timothy Shawn; Rohrer, Brandon Robinson; Walker, Charles A.; Ho, Clifford K.. et al.
Partner: UNT Libraries Government Documents Department

Accidental Drop of a Carbon Steel/Lead Shipping Cask (HFEF 14) at Low Temperatures

Description: A shielded cask is used to transport radioactive materials between facilities at the Idaho National Laboratory. The cask was fabricated with an outer and inner shell of A36 carbon steel with lead poured in the annular space between the shells to provide radiation shielding. Carbon steel is known to be susceptible to low-temperature brittle fracture under impact loading. This paper will present the analysis results representing postulated transportation accidents during on-site transfers of the cask at subzero temperatures. The accident scenarios were based on a series of cask drops onto a rigid surface from a height of 1.83m (6 ft.) Finite element models of the cask and its contents were solved and post processed using the ABAQUS software. Each model was examined for failure to contain radioactive materials and/or significant loss of radiation shielding. Results of these analyses show that the body of the cask exhibits considerable ruggedness and will remain largely intact after the impact. There will be deformation of the main cask body with localized brittle failure of the cask outer shell and door structure. The cask payload outer waste can remains in the cask but will experience some permanent plastic deformation in each drop. It will not be deformed to the point where it will rupture, thus maintaining confinement of the can contents.
Date: August 1, 2007
Creator: Hawkes, Brian D. & Nitzel, Michael E.
Partner: UNT Libraries Government Documents Department

Development of a Demagnetization Refrigerator for Solid State Research and Education

Description: The objective of this project is to develp an instrument to cool electrons in semiconductors to extremely low temperatures (lower than 1 millikelvin), a unique capability that would allow studies of new states of matter formed by low-dimensional electrons. At such low temperatures (and with an intense magnetic field), electronic behavior differs completely from ordinary ones observed at room temperatures. Studies of electrons at such low temperatures would open the door for fundamental discoveries in condensed matter physics. Understanding low-temperature electron transport in low-dimensional and nano-scale devices is the foundation for developing next generation quantum information and quantum computation technologies. The primary material systems for such investigations will be ultra-high quality GaAs/AlGaAs quantum structures grown by molecular beam epitaxy, materials that are widely used in lasers and telecommunications.
Date: November 15, 2006
Creator: Du, Rui-Rui
Partner: UNT Libraries Government Documents Department