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FAA Alaska: Weak Controls Resulted in Improper and Wasteful Purchases (open access)

FAA Alaska: Weak Controls Resulted in Improper and Wasteful Purchases

A letter report issued by the General Accounting Office with an abstract that begins "GAO reviewed purchasing controls and activities within the Airway Facilities Division of the Federal Aviation Administration (FAA) in Alaska. This unit, referred to as AFA, is responsible for maintaining airway navigation and communication equipment throughout the state. AFA implemented a pilot program in March 1997 called the Corporate Maintenance Philosophy (CMP) that reduced periodic maintenance and certification requirements for equipment, thus allowing AFA to work with fewer staff. Under this program, AFA's funds originally intended for payroll compensation and benefits were freed for use on capital improvements and an employee recognition system. However, AFA did not have good internal controls. GAO reviewed 150 purchases made in fiscal years 1999 through 2001. Of these, 118 did not comply with one or more FAA purchasing requirements. AFA's highly decentralized operating environment made it susceptible to internal controls weaknesses and improper or wasteful purchases. FAA headquarters in Washington, DC, provides little oversight of spending practices, and regional officials in Alaska have no oversight authority over AFA's practices. AFA personnel work in various locations, with more than half having agency credit cards. GAO found that most cardholders received no training …
Date: May 30, 2002
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Waste Cleanup: Status and Implications of DOE's Compliance Agreements (open access)

Waste Cleanup: Status and Implications of DOE's Compliance Agreements

A letter report issued by the General Accounting Office with an abstract that begins "The Department of Energy (DOE) spends between $6 billion and $7 billion annually to store, clean up, and monitor nuclear and hazardous waste at its sites. Various federal and state agencies with jurisdiction over environmental and health issues related to the cleanup are therefore involved in regulating and overseeing DOE's activities. Much of the cleanup activity has been implemented under compliance agreements between the DOE and these agencies. There are three types of compliance agreements governing DOE's sites: (1) legal requirements that address the cleanup of federal sites on the National Priorities List of the nation's most serious hazardous waste sites or that address treatment and storage of mixed hazardous and radioactive waste at DOE facilities; (2) court-ordered agreements resulting from lawsuits initiated primarily by states; and (3) other agreements, such as state administrative orders enforcing state hazardous waste management laws, that do not fall into the first two categories. Through the end of fiscal year 2001, DOE had completed 4,500 milestones, although for several reasons, the number of milestones is not a good indication of cleanup progress. Many of the milestones are administrative in nature, …
Date: May 30, 2002
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Tennessee Valley Authority: Information on Benchmarking and Electricity Rates (open access)

Tennessee Valley Authority: Information on Benchmarking and Electricity Rates

A letter report issued by the General Accounting Office with an abstract that begins "The Tennessee Valley Authority (TVA) declared its intent to become competitive by reducing its cost of power and becoming more financially flexible by reducing debt from $27.4 billion to $13.2 billion by 2007. Since the 1980s, TVA has used benchmarking to assess staffing levels for its nuclear program and it began to use benchmarking studies for its non-nuclear business units in 1998. Recent studies indicate that TVA's nuclear and transmission power supply units are close to the industry's best in terms of staffing efficiency. TVA has taken several actions to improve performance and efficiency, including reorganizing its human resources and business services organizations and automating its hydropower production facilities to reduce future staffing. TVA continues to utilize benchmarking to assist in identifying opportunities for improvement. TVA's current electricity rates are low when compared to 12 likely competitors and to national averages. Although TVA's electricity rates are relatively low, it is legislatively protected from most competition, and it has the statutory authority to raise rates. If TVA were to choose to raise electricity rates selectively and use the additional cash generated to repay debt, it could accelerate …
Date: May 30, 2002
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
A 2-Liter, 2000 MPa Air Source for the Radiatively Driven Hypersonic Wind Tunnel (open access)

A 2-Liter, 2000 MPa Air Source for the Radiatively Driven Hypersonic Wind Tunnel

The A2 LITE is a 2 liter, 2000 MPa, 750 K ultra-high pressure (UHP) vessel used to demonstrate UHP technology and to provide an air flow for wind tunnel nozzle development. It is the largest volume UHP vessel in the world. The design is based on a 100:1 pressure intensification using a hydraulic ram as a low pressure driver and a three-layer compound cylinder UHP section. Active control of the 900 mm piston stroke in the 63.5 mm bore permits pressure-time profiles ranging from static to constant pressure during flow through a 1 mm throat diameter nozzle for 1 second.
Date: May 30, 2002
Creator: Costantino, M & Lofftus, D
Object Type: Article
System: The UNT Digital Library
Electrochemical Behavior of Alloy 22 in 5 M CaC12 (open access)

Electrochemical Behavior of Alloy 22 in 5 M CaC12

The corrosion resistance of Alloy 22 (UNS No.: N06022) was studied in 5 M CaCl{sub 2} electrolyte at various temperatures. Potentiodynamic polarization was used to examine the electrochemical behavior and measure the key potentials. Alloy 22 was found to be susceptible to localized corrosion in this high chloride [10M Cl{sup -}] environment at temperatures as low as 6O C.
Date: May 30, 2002
Creator: Ilevbare, G O
Object Type: Article
System: The UNT Digital Library
Texas Stonewall Democratic Caucus 2000-2002 Officers and Board of Directors (open access)

Texas Stonewall Democratic Caucus 2000-2002 Officers and Board of Directors

List consists of 2000-2002 Officers and Board of Directors' addresses and other contact information.
Date: May 30, 2002
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Comanche Chief (Comanche, Tex.), No. 4, Ed. 1 Thursday, May 30, 2002 (open access)

Comanche Chief (Comanche, Tex.), No. 4, Ed. 1 Thursday, May 30, 2002

Weekly newspaper from Comanche, Texas that includes local, state, and national news along with advertising.
Date: May 30, 2002
Creator: Wilkerson, James C., III
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 17, No. 21, Ed. 1 Thursday, May 30, 2002 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 17, No. 21, Ed. 1 Thursday, May 30, 2002

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: May 30, 2002
Creator: Ritch, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Polk County Enterprise (Livingston, Tex.), Vol. 120, No. 43, Ed. 1 Thursday, May 30, 2002 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 120, No. 43, Ed. 1 Thursday, May 30, 2002

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: May 30, 2002
Creator: White, Barbara
Object Type: Newspaper
System: The Portal to Texas History
Hondo Anvil Herald (Hondo, Tex.), Vol. 116, No. 22, Ed. 1 Thursday, May 30, 2002 (open access)

Hondo Anvil Herald (Hondo, Tex.), Vol. 116, No. 22, Ed. 1 Thursday, May 30, 2002

Weekly newspaper from Hondo, Texas that includes local, state, and national news along with extensive advertising.
Date: May 30, 2002
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Toxic Substances From Coal Combustion--a Comprehensive Assessment, Phase Ii: Element Modes of Occurrence for the Ohio 5/6/7, Wyodak and North Dakota Coal Samples (open access)

Toxic Substances From Coal Combustion--a Comprehensive Assessment, Phase Ii: Element Modes of Occurrence for the Ohio 5/6/7, Wyodak and North Dakota Coal Samples

This study reports on the second phase (Phase II) of USGS research activities in support of DOE contract DE-AC22-95PC95101 ''Toxic Substances From Coal Combustion--A Comprehensive Assessment'', funded under DOE Interagency Agreement DE-AI22-95PC95145. The purpose of the study was to provide a quantitative and semi-quantitative characterization of the modes of occurrence of trace elements in coal samples investigated under Phase II, including (1) Ohio 5/6/7, an Ohio bituminous coal sample blended from the No.5, No.6, and No.7 beds; (2) North Dakota, a lignite sample from the Falkirk Mine, Underwood, ND, and (3) Wyodak, a sub-bituminous coal sample from the Cordero Mine, Gillette, WY. Samples from these coal beds were selected for their range in rank and commercial applicability. Results of this research provide basic information on the distribution of elements in Phase II coal samples, information needed for development of a commercial predictive model for trace-element behavior during coal combustion.
Date: May 30, 2002
Creator: Kolker, Allan; Mroczkowski, Stanley J.; Palmer, Curtis A.; Dennen, Kristen O.; Finkelman, Robert B. & Jr., John H. Bullock
Object Type: Report
System: The UNT Digital Library
Mechanical and thermal analysis of beryllium windows for RF cavities in a muon cooling channel (open access)

Mechanical and thermal analysis of beryllium windows for RF cavities in a muon cooling channel

Thin beryllium windows (foils) may be utilized to increase shunt impedance of closed-cell RF cavities. These windows are subject to ohmic heating from RF currents. The resulting temperature gradients in the windows can produce out of plane displacements that detune the cavity frequency. The window displacement can be reduced or eliminated by pre-stressing the foils in tension. Because of possible variations during manufacture, it is important to quantify the actual prestress of a Be window before it is put into service. We present the thermal and mechanical analyses of such windows under typical operating conditions and describe a simple non-destructive means to quantify the pre-stress using the acoustic signature of a window. Using finite element analysis, thin plate theory and physical measurements of the vibration modes of a window we attempted to characterize the actual Be window pre-stress in a small number of commercially sourced windows (30% of yield strength is typical). This method can be used for any window material and size, but this study focused on 16 cm diameter Be Windows ranging in thickness from 125 microns to 508 microns and with varying pre-stresses. The method can be used to nondestructively test future Be windows for the desired …
Date: May 30, 2002
Creator: Li, Derun; Ladran, A.; Lozano, D. & Rimmer, R.
Object Type: Article
System: The UNT Digital Library
Synchronization of x-ray pulses to the pump laser in an ultrafast x-ray facility (open access)

Synchronization of x-ray pulses to the pump laser in an ultrafast x-ray facility

Accurate timing of ultrafast x-ray probe pulses emitted from a synchrotron radiation source with respect to a pump laser exciting processes in the sample under study is critical for the investigation of structural dynamics in the femtosecond regime. We describe a scheme for synchronizing femtosecond x-ray pulses relative to a pump laser. X-ray pulses of <100 fs duration are generated from a proposed source based on a recirculating superconducting linac [1,2,3]. Short x-ray pulses are obtained by a process of electron pulse compression, followed by transverse temporal correlation of the electrons, and ultimately x-ray pulse compression. Timing of the arrival of the x-ray pulse with respect to the pump laser is found to be dominated by the operation of the deflecting cavities which provide the transverse temporal correlation of the electrons. The deflecting cavities are driven from a highly stable RF signal derived from a modelocked laser oscillator which is also the origin of the pump l aser pulses.
Date: May 30, 2002
Creator: Corlett, J.N.; Barry, W.; Byrd, J.M.; Schoenlein, R. & Zholents, A.
Object Type: Article
System: The UNT Digital Library
Effect of Trapped Energetic Ions on MHD Activity in Spherical Tori (open access)

Effect of Trapped Energetic Ions on MHD Activity in Spherical Tori

It is shown that the increase of beta (the ratio of plasma pressure to the magnetic field pressure) may change the character of the influence of trapped energetic ions on MHD stability in spherical tori. Namely, the energetic ions, which stabilize MHD modes (such as the ideal-kink mode, collisionless tearing mode, and semi-collisional tearing mode) at low beta, have a destabilizing influence at high beta unless the radial distribution of the energetic ions is very peaked.
Date: May 30, 2002
Creator: White, R. B.; Kolesnichenko, Ya. I.; Lutsenko, V. V. & Marchenko, V. S.
Object Type: Report
System: The UNT Digital Library
Analysis of formulas used in coupling impedance coaxial-wire measurements for distributed impedances (open access)

Analysis of formulas used in coupling impedance coaxial-wire measurements for distributed impedances

In this paper we study the validity of coupling impedance bench measurements for distributed impedances, comparing the commonly used log formula to the result obtained applying a modified version of Bethe's theory of diffraction to a long slot in a coaxial beam pipe. The equations found provide a quantitative expression for the influence of the wire thickness used in the measurement of the real and imaginary part of the longitudinal impedance. The precision achievable in an actual measurement is therefore discussed. The method presented has also been applied in the presence of lumped impedances [1].
Date: May 30, 2002
Creator: De Santis, Stefano
Object Type: Article
System: The UNT Digital Library
Hydrogen Storage Properties of Lithium Aluminohydride modified by dopants and mechanochemistry (open access)

Hydrogen Storage Properties of Lithium Aluminohydride modified by dopants and mechanochemistry

Alkali metal aluminohydrides have high potential as solid hydrogen storage materials. They have been known for their irreversible dehydrogenation process below 100 atm until Bogdanovic et al [1, 2] succeeded in the re-hydrogenation of NaAlH{sub 4} below 70 atm. They achieved 4 wt.% H{sub 2} reversible capacity by doping NaAlH{sub 4} with Ti and/or Fe organo-metalic compounds as catalysts. This suggests that other alkali and, possibly alkaline earth metal aluminohydrides can be used for reversible hydrogen storage when modified by proper dopants. In this research, Zr{sub 27}Ti{sub 9}Ni{sub 38}V{sub 5}Mn{sub 16}Cr{sub 5}, LaNi{sub 4.85}Sn{sub 0.15}, Al{sub 3}Ti, and PdCl{sub 2} were combined with LiAlH{sub 4} by ball-milling to study whether or not LiAlH{sub 4} is capable to both absorb and desorb hydrogen near ambient conditions. X-ray powder diffraction, differential thermal analysis, and scanning electron microscopy were employed for sample characterizations. All four compounds worked as catalysts in the dehydrogenation reactions of both LiAlH{sub 4} and Li{sub 3}AlH{sub 6} by inducing the decomposition at lower temperature. However, none of them was applicable as catalyst in the reverse hydrogenation reaction at low to moderate hydrogen pressure.
Date: May 30, 2002
Creator: Hosokawa, Keita
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Physical Properties of Intermetallic FE2VA1 (open access)

Physical Properties of Intermetallic FE2VA1

Fe{sub 2}VAl has recently been discovered to have a negative temperature coefficient of resistivity, moderately enhanced specific heat coefficient, and a large DOS at the Fermi level by photoemission. This triggered a round of heated research to understand the ground state of this material, both theoretically and experimentally. here they report a comprehensive characterization of Fe{sub 2}VAl. X-ray diffraction exhibited appreciable antisite disorder in all of our samples. FTIR spectroscopy measurements showed that the carrier density and scattering time had little sample-to-sample variation or temperature dependence for near-stoichiometric samples. FTIR and DC resistivity suggest that the transport properties of Fe{sub 2}VAl are influenced by both localized and delocalized carriers, with the former primarily responsible for the negative temperature coefficient of resistivity. Magnetization measurements reveal that near-stoichiometric samples have superparamagnetic clusters with at least two sizes of moments. X-ray photoemission from Fe core level showed localized magnetic moments on site-exchanged Fe. They conclude that in Fe{sub 2}VAl, antisite disorder causes significant modification to the semi-metallic band structure proposed by LDA calculations. With antisite disorder considered, they are now able to explain most of the physical properties of Fe{sub 2}VAl.
Date: May 30, 2002
Creator: Feng, Ye
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Initial results from model independent analysis of the KEK ATF (open access)

Initial results from model independent analysis of the KEK ATF

Model Independent Analysis (MIA) has shown the potential to be a useful tool for diagnostics and optics verification. The Accelerator Test Facility (ATF) prototype damping ring at KEK has a diagnostic system with the ability to collect data allowing the application of MIA for analysis of the injection stability, and the storage ring optics and diagnostics. Understanding of all these issues will be important for improving the operational performance of a damping ring. We report here the results of a first attempt to apply MIA to the ATF.
Date: May 30, 2002
Creator: Wolski, A.; Ross, M.C.; Woodley, M.D. & Nelson, J.
Object Type: Article
System: The UNT Digital Library
Thermal Response of Tritiated Co-deposits from JET and TFTR to Transient Heat Pulses (open access)

Thermal Response of Tritiated Co-deposits from JET and TFTR to Transient Heat Pulses

High heat flux interactions with plasma-facing components have been studied at microscopic scales. The beam from a continuous wave neodymium laser was scanned at high speed over the surface of graphite and carbon fiber composite tiles that had been retrieved from TFTR (Tokamak Fusion Test Reactor) and JET (Joint European Torus) after D-T plasma operations. The tiles have a surface layer of amorphous hydrogenated carbon that was co-deposited during plasma operations, and laser scanning has released more than 80% of the co-deposited tritium. The temperature rise of the co-deposit was much higher than that of the manufactured material and showed an extended time history. The peak temperature varied dramatically (e.g., 1,436 C compared to >2,300 C), indicating strong variations in the thermal conductivity to the substrate. A digital microscope imaged the co-deposit before, during, and after the interaction with the laser and revealed 100-micron scale hot spots during the interaction. Heat pulse durations of order 100 ms resulted in brittle destruction and material loss from the surface, whilst a duration of =10 ms showed minimal changes to the co-deposit. These results show that reliable predictions for the response of deposition areas to off-normal events such as ELMs (edge-localized modes) and …
Date: May 30, 2002
Creator: Skinner, C. H.; Bekrisl, N.; Coad, J. P.; Gentile, C. A.; Hassanein, A.; Reiswig, R. et al.
Object Type: Report
System: The UNT Digital Library
A Recirculating Linac Based Synchrotron Light Source for Ultrafast X-Ray Science (open access)

A Recirculating Linac Based Synchrotron Light Source for Ultrafast X-Ray Science

LBNL is pursuing a multi-divisional initiative that has this year further developed design studies and the scientific program for a facility dedicated to the production of x-ray pulses with ultra-short time duration. Our proposed x-ray facility [1] has the short x-ray pulse length ({approx};60 fs FWHM) necessary to study very fast dynamics, high flux (approximately 1011 photons/sec/0.1 percentBW) to study weakly scattering systems, and tuneability over 1-10 keV photon energy. The photon production section of the machine accomodates seven 2m long undulators and six 2T field dipole magnets. The x-ray pulse repetition rate of 10 kHz is matched to studies of dynamical processes (initiated by ultra-short laser pulses) that typicaly have a long recovery time or are not generally cyclic or reversible and need time to allow relaxation, replacement, or flow of the sample. The technique for producing ultra-short x-ray pulses uses relatively long electron bunches to minimise high-peak-current collective effects, and the ultimate x-ray duration is achieved by a combination of bunch manipulation and optical compression.
Date: May 30, 2002
Creator: Corlett, J.N.; Barry, W.; Byrd, J.M.; DeSantis, S.; Heimann, P.; Lidia, S. et al.
Object Type: Article
System: The UNT Digital Library
Tritium Removal from JET and TFTR Tiles by a Scanning Laser (open access)

Tritium Removal from JET and TFTR Tiles by a Scanning Laser

Fast and efficient tritium removal is needed for future D-T machines with carbon plasma-facing components. A novel method for tritium release has been demonstrated on co-deposited layers on tiles retrieved from the Tokamak Fusion Test Reactor (TFTR) and from the Joint European Torus (JET). A scanning continuous wave neodymium laser beam was focused to =100 W/mm2 and scanned at high speed over the co-deposits, heating them to temperatures =2000 C for about 10 ms in either air or argon atmospheres. Fiber optic coupling between the laser and scanner was implemented. Up to 87% of the co-deposited tritium was thermally desorbed from the JET and TFTR samples. This technique appears to be a promising in-situ method for tritium removal in a next-step D-T device as it avoids oxidation, the associated de-conditioning of the plasma-facing surfaces, and the expense of processing large quantities of tritium oxide.
Date: May 30, 2002
Creator: Skinner, C. H.; Bekris, N.; Coad, J. P.; Gentile, C. A. & Glugla, M.
Object Type: Report
System: The UNT Digital Library
Overview of collective effects in the NLC main damping rings (open access)

Overview of collective effects in the NLC main damping rings

The present design for the NLC Main Damping Rings (MDRs) meets the specifications for acceptance and extracted emittance, in the limit of zero current. However, the relatively large bunch charge and moderate energy mean that a variety of collective effects can impact the beam dynamics, leading to loss of stability or increase of equilibrium emittance. These effects include intrabeam scattering, impedance from numerous sources, fast ion instability, and (in the positron ring) electron cloud. In this note, we survey the expected impact on damping ring performance from each of a number of collective effects, and discuss the priorities for future studies in this area.
Date: May 30, 2002
Creator: Wolski, A. & de Santis, S.
Object Type: Article
System: The UNT Digital Library
High power RF test of an 805 MHz RF cavity for a muon cooling channel (open access)

High power RF test of an 805 MHz RF cavity for a muon cooling channel

We present recent high power RF test results on an 805 MHz cavity for a muon cooling experiment at Lab G in Fermilab. In order to achieve high accelerating gradient for large transverse emittance muon beams, the cavity design has adopted a pillbox like shape with 16 cm diameter beam iris covered by thin Be windows, which are demountable to allow for RF tests of different windows. The cavity body is made from copper with stiff stainless steel rings brazed to the cavity body for window attachments. View ports and RF probes are available for visual inspections of the surface of windows and cavity and measurement of the field gradient. Maximum of three thermo-couples can be attached to the windows for monitoring the temperature gradient on the windows caused by RF heating. The cavity was measured to have Q{sub 0} of about 15,000 with copper windows and coupling constant of 1.3 before final assembling. A 12 MW peak power klystron is available at Lab G in Fermilab for the high power test. The cavity and coupler designs were performed using the MAFIA code in the frequency and the time domain. Numerical simulation results and cold test measurements on the cavity …
Date: May 30, 2002
Creator: Li, Derun; Corlett, J.; MacGill, R.; Rimmer, R.; Wallig, J.; Zisman, M. et al.
Object Type: Article
System: The UNT Digital Library
Symmetry-Breaking Transitions in RECuAs2-xPx (RE=Sm, Gd, Ho, and Er) (open access)

Symmetry-Breaking Transitions in RECuAs2-xPx (RE=Sm, Gd, Ho, and Er)

None
Date: May 30, 2002
Creator: Mozharivskyj, Yurij
Object Type: Thesis or Dissertation
System: The UNT Digital Library