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Nitrogen trailer acceptance test report

Description: This Acceptance Test Report documents compliance with the requirements of specification WHC-S-0249. The equipment was tested according to WHC-SD-WM-ATP-108 Rev.0. The equipment being tested is a portable contained nitrogen supply. The test was conducted at Norco`s facility.
Date: February 12, 1996
Creator: Kostelnik, A.J.
Partner: UNT Libraries Government Documents Department

The Development of 6061-Aluminum Windows for the MICE LiquidAbsorber

Description: The thin windows for the Muon Ionization Cooling Experiment (MICE) liquid Absorber will be fabricated from 6061-T6-aluminum. The absorber and vacuum vessel thin windows are 300-mm in diameter and are 180 mm thick at the center. The windows are designed for an internal burst pressure of 0.68 MPa (100 psig) when warm. The MICE experiment design calls for changeable windows on the absorber, so a bolted window design was adopted. Welded windows offer some potential advantages over bolted windows when they are on the absorber itself. This report describes the bolted window and its seal. This report also describes an alternate window that is welded directly to the absorber body. The welded window design presented permits the weld to be ground off and re-welded. This report presents a thermal FEA analysis of the window seal-weld, while the window is being welded. Finally, the results of a test of a welded-window are presented.
Date: August 24, 2005
Creator: Lau, W.; Yang, S.Q.; Green, M.A.; Ishimoto, S. & Swanson, J.
Partner: UNT Libraries Government Documents Department

Implications for the Cryogenic Fielding of Leaking Beryllium Capsules

Description: In this paper we show that the ambient temperature measured leakage time constant, {tau}{sub RT}, is related to the leakage at cryogenic temperature, R{sub C}, by R{sub C}= 0.23{rho}{sub DT}V{sub sh}/ {tau}{sub RT} where {rho}{sub DT} is the density of cryogenic DT vapor, and V{sub sh} is the internal volume of the shell. We then calculate the size of voids that may result from leakage at the Be/DT interface, depending upon the number of leakage sites and {tau}{sub RT}. Even for the slowest leakers the potential void growth is excessive. Reasons that voids have not been seen in DT layering experiments to date include the lack of a technique to see isolated micronish bubbles, however possible mechanisms preventing void formation are also discussed.
Date: February 20, 2007
Creator: Cook, R
Partner: UNT Libraries Government Documents Department


Description: Increased activities in Cryogenic Engineering have brought about the need for a compilation of available data. The purpose of the Cryogenic Data Book is to provide a condensed source of reliable data and reference information for those working in the cryogenic field. Specifically the data were compiled with a view toward the design of liquid hydrogen bubble chambers.
Date: May 15, 1956
Creator: Engineerin, National Bureau of Standards. Cryogenic; Chelton, Dudley B.; Mann, Douglas B.; Byrns, R.A. & Hoard, H.S.
Partner: UNT Libraries Government Documents Department


Date: September 22, 2003
Partner: UNT Libraries Government Documents Department

Development of 0.5-5 W, 10K Reverse Brayton Cycle Cryocoolers - Phase II Final Report

Description: Miniature cryocoolers for the 8-30 K range are needed to provide 0.5-5 w of cooling to high sensitivity detectors (for long-wave-length IR, magnetism, mm-wave, X-ray, dark matter, and possibly y-ray detection) while maintaining low mass, ultra-low vibration, and good efficiency. This project presents a new approach to eliminating the problems normally encountered in efforts to build low-vibration, fieldable, miniature cryocoolers. Using the reverse Brayton Cycle (RBC), the approach applies and expands on existing spinner technology previously used only in Nuclear Magnetic Resonance (NMR) probes.
Date: October 15, 2001
Creator: Doty, F. D.; Boman, A.; Arnold, S.; Spitzmesser, J. B.; Jones, D.; McCree, D. et al.
Partner: UNT Libraries Government Documents Department

Cryogenic Treatment of Production Components in High-Wear Rate Wells

Description: Deep Cryogenic Tempering (DCT) is a specialized process whereby the molecular structure of a material is ''re-trained'' through cooling to -300 F and then heating to +175-1100 F. Cryocon, Inc. (hereafter referred to as Cryocon) and RMOTC entered an agreement to test the process on oilfield production components, including rod pumps, rods, couplings, and tubing. Three Shannon Formation wells were selected (TD about 500 ft) based on their proclivity for high component wear rates. Phase 1 of the test involved operation for a nominal 120 calendar day period with standard, non-treated components. In Phase 2, treated components were installed and operated for another nominal 120 calendar day period. Different cryogenic treatment profiles were used for components in each well. Rod pumps (two treated and one untreated) were not changed between test phases. One well was operated in pumped-off condition, resulting in abnormal wear and disqualification from the test. Testing shows that cryogenic treatment reduced wear of rods, couplers, and pump barrels. Testing of production tubing produced mixed results.
Date: April 29, 2002
Creator: Milliken, M.
Partner: UNT Libraries Government Documents Department

CEBAF cryogenic system

Description: The CEBAF cryogenic system consists of 3 refrigeration systems: Cryogenic Test Facility (CTF), Central Helium Liquefier (CHL), and End Station Refrigerator (ESR). CHL is the main cryogenic system for CEBAF, consisting of a 4.8 kW, 2.0 K refrigerator and transfer line system to supply 2.0 K and 12 kW of 50 K shield refrigeration for the Linac cavity cryostats and 10 g/s of liquid for the end stations. This paper describes the 9-year effort to commission these systems, concentrating on CHL with the cold compressors. The cold compressors are a cold vacuum pump with an inlet temperature of 3 K which use magnetic bearings, thereby eliminating the possibility of air leaks into the subatmospheric He.
Date: December 31, 1995
Partner: UNT Libraries Government Documents Department

The CEBAF control system for the CHL

Description: The CEBAF Central Helium Liquefier (CHL) control system consists of independent safety controls located at each subsystem, CAMAC computer interface hardware, and a CEBAF-designed control software called Thaumaturgic Automated Control Logic (TACL). The paper describes how control software was interfaced with the subsystems of the CHL. Topics of configuration, editing, operator interface, datalogging, and internal logic functions are presented as they relate to the operational needs of the helium plant. The paper also describes the effort underway to convert from TACL to the Experimental Physics and Industrial Control System (EPICS), the new control system for the CEBAF accelerator. This software change will require customizing EPICS software to cryogenic process control.
Date: August 1, 1996
Creator: Keesee, M.S. & Bevins, B.S.
Partner: UNT Libraries Government Documents Department

The cryogenics of the LHC interaction region final focus superconducting magnets

Description: The LHC interaction region final focus magnets will include four superconducting quadrupoles cooled with pressurized, static superfluid helium at 1.9 K. The heat absorbed in pressurized He II, which may be more than 10 Watts per meter due to dynamic heating from the particle beam halo, will be transported to saturated He II at 1.8 K and removed by the 16 mbar vapor. This paper discusses the conceptual design for the cryogenics of the interaction region final focus superconducting magnets and the integration of this magnet system into the overall LHC cryogenic system.
Date: August 1, 1998
Creator: Byrns, R. & et al., FNAL
Partner: UNT Libraries Government Documents Department

Why cryogenically cooled, thin crystals handle extremely high power densities

Description: Recently, a new type of cryogenically cooled high heat load monochromator was proposed and, developed at Argonne National Laboratory and tested at European Synchrotron Radiation Facility (ESRF.) These tests showed that powers of 153 W and power densities of 450 W/mm{sup 2} cause only negligible strain. These powers and power densities are larger than will be absorbed by the first crystal on an undulator beamline at the Advanced Photon Source (APS). In our earlier work we suggested that the crystal might show strain at much lower values of the powers and power densities. We now can explain the ESRF results in terms of the unique role the negative thermal expansion coefficient of Si plays in minimizing strain.
Date: September 1, 1995
Creator: Knapp, G.S.; Jennings, G. & Beno, M.A.
Partner: UNT Libraries Government Documents Department

Reference Tables for Low-Temperature Thermocouples

Description: Report discussing the completed experimental program of the low-temperature reference tables for the commonly used thermocouples. Details of the experimental system, instrumentation, data analysis, error analysis, and materials tested are given in order to allow the user to better evaluate and apply the results.
Date: June 1972
Creator: Sparks, Larry L.; Powell, Robert L. & Hall, William J.
Partner: UNT Libraries Government Documents Department

Cryogenic tests of the g-2 superconducting solenoid magnet system

Description: The g-2 muon storage ring magnet system consists of four large superconducting solenoids that are up to 15.1 m in diameter. The g-2 superconducting solenoids and a superconducting inflector dipole will be cooled using forced two-phase helium in tubes. The forced two-phase helium cooling will be provided from the J-T circuit of a refrigerator that is capable of delivering 625 W at 4.5 K. The two-phase helium flows from the refrigerator J-T circuit through a heat exchanger in a storage dewar that acts as a phase separator for helium returning from the magnets. The use of a heat exchanger in the storage dewar reduces the pressure drop in the magnet flow circuit, eliminates most two phase flow oscillations, and it permits the magnets to operate at variable thermal loads using the liquid in the storage dewar as a buffer. The g-2 magnet cooling system will consist of three parallel two-phase helium flow circuits that provide cooling to the following components: (1) the four large superconducting solenoids, (2) the current interconnects between the solenoids and the solenoid gas cooled electrical leads, and (3) the inflector dipole and its gas cooled electrical leads. This report describes a cryogenic test of the two 15.1 meter diameter superconducting solenoids using two-phase helium from a dewar. The report describes the cool down procedure for the 3.5 ton outer solenoid magnet system using liquid nitrogen and two-phase helium. Low current operation of the outer solenoids is discussed.
Date: August 1995
Creator: Jia, L. X.; Cullen, J. R. ,Jr. & Esper, A. J.
Partner: UNT Libraries Government Documents Department

Neutron Detection with Cryogenics and Semiconductors

Description: The common methods of neutron detection are reviewed with special attention paid to the application of cryogenics and semiconductors to the problem. The authors' work with LiF- and boron-based cryogenic instruments is described as well as the use of CdTe and HgI{sub 2} for direct detection of neutrons.
Date: March 10, 2005
Creator: Bell, Z. W.; Carpenter, D. A.; Cristy, S. S. & Lamberti, V. E.
Partner: UNT Libraries Government Documents Department

Equation of State Measurements in Liquid Deuterium to 70 Gpa

Description: Using intense magnetic pressure, a method was developed to launch flyer plates to velocities in excess of 20 km/s. This technique was used to perform plate-impact, shock wave experiments on cryogenic liquid deuterium (LD{sub 2}) to examine its high-pressure equation of state (EOS). Using an impedance matching method, Hugoniot measurements were obtained in the pressure range of 30-70 GPa. The results of these experiments disagree with previously reported Hugoniot measurements of LD{sub 2} in the pressure range above {approx}40 GPa, but are in good agreement with first principles, ab-initio models for hydrogen and its isotopes.
Date: December 1, 2001
Partner: UNT Libraries Government Documents Department

Evolution of the rf systems layout for the SSC collider rings

Description: This note contains information on the results of ongoing reviews concerning the basic design of the 360-MHz rf systems for the 2 {times} 20 TeV Superconducting Super Collider (SSC). For generation of 20-MV peak voltage per ring, with proton beams of 2 {times} 70 mA, several versions have been investigated: Version A (baseline design and modified baseline): 2 {times} 8 five-cell normalconducting cavities; Version B: 2 {times} 24 single-cell normalconducting cavities; and Version C: 2 {times} 8 or 2 {times} 10 single-cell superconducting cavities. For reasons of easier High Order Mode (HOM) damping, multicell cavities have been found inferior in performance when compared to single cells. Superconducting cavities have been found superior in handling transient beam loading when compared to normalconducting cavities. A threefold higher voltage, and a reduced R/Q value of superconducting cells lead to a ninefold increase in stored electromagnetic energy which, by the same factor, reduces the speed of phase changes originating from notches in the circulating beams. The theoretical possibility to operate superconducting cavities half-detuned in order to supply reactive power to the beam may also lead to considerable savings in overall power consumption. On the other hand, many challenges are involved with the use of superconducting cavities, such as the delicacy of the superconductive state, the complexity of cryostat design and operation, tuning requirements, sensitivity to vibration, and other issues.
Date: October 1, 1993
Creator: Schaffer, G.
Partner: UNT Libraries Government Documents Department

In situ freeze-capturing of fracture water using cryogenic coring

Description: Current methods do not allow for sampling of in situ water from unsaturated fractures in low-moisture environments. A novel cryogenic coring technique based on the method developed by Simon and Cooper (1996) is used to collect in situ water in unsaturated fractures. This method uses liquid nitrogen as the drilling fluid, which can freeze the fracture water in place while coring. Laboratory experiments are conducted to demonstrate that water in an unsaturated fracture can be frozen and collected using cryogenic coring.
Date: January 29, 2004
Creator: Su, Grace W.; Wang, Joseph S.Y. & Zacny, Kris
Partner: UNT Libraries Government Documents Department

A novel 3D wavelet based filter for visualizing features in noisy biological data

Description: We have developed a 3D wavelet-based filter for visualizing structural features in volumetric data. The only variable parameter is a characteristic linear size of the feature of interest. The filtered output contains only those regions that are correlated with the characteristic size, thus denoising the image. We demonstrate the use of the filter by applying it to 3D data from a variety of electron microscopy samples including low contrast vitreous ice cryogenic preparations, as well as 3D optical microscopy specimens.
Date: January 5, 2005
Creator: Moss, W C; Haase, S; Lyle, J M; Agard, D A & Sedat, J W
Partner: UNT Libraries Government Documents Department

Helium Pot System for Maintaining Sample Temperature after Cryocooler Deactivation

Description: A system for maintaining a sample at a constant temperature below 10K after deactivating the cooling source is demonstrated. In this system, the cooling source is a GM cryocooler that is joined with the sample through an adaptor that consists of a helium pot and a resistive medium. Upon deactivating the cryocooler, the power applied to a heater located on the sample side of the resistive medium is decreased gradually to maintain an appropriate temperature rise across the resistive medium as the helium pot warms. The temperature is held constant in this manner without the use of solid or liquid cryogens and without mechanically disconnecting the sample from the cooler. Shutting off the cryocooler significantly reduces sample motion that results from vibration and expansion/contraction of the cold head housing. The reduction in motion permits certain processes that are very sensitive to sample position stability, but are not performed throughout the duration that the sample is at low-temperature. An apparatus was constructed to demonstrate this technique using a 4K GM cryocooler. Experimental and theoretical predictions indicate that when the helium pot is pressurized to the working pressure of the cryocooler's helium supply, a sample with continuous heat dissipation of several-hundred milliwatts can be maintained at 7K for several minutes when using an extension that increases the cold head length by less than 50%.
Date: January 26, 2005
Creator: Haid, B J
Partner: UNT Libraries Government Documents Department