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0.5 μm E/D AlGaAs/GaAs heterostructure field effect transistor technology with DFET threshold adjust implant

Description: A doped-channel heterostructure field effect transistor (H-FET) technology has been developed with self-aligned refractory gate processing and using both enhancement- and depletion-mode transistors. D-HFET devices are obtained with a threshold voltage adjust implant into material designed for E-HFET operation. Both E- and D-HFETs utilize W/WSi bilayer gates, sidewall spacers, and rapid thermal annealing for controlling short channel effects. The 0.5 {mu}m E- HFETs (D-HFETs) have been demonstrated with transconductance of 425 mS/mm (265-310 mS/mm) and f{sub t} of 45-50 GHz. Ring oscillator gate delays of 19 ps with a power of 0.6 mW have been demonstrated using direct coupled FET logic. These results are comparable to previous doped-channel HFET devices and circuits fabricated by selective reactive ion etching rather than ion implantation for threshold voltage adjustment.
Date: April 1997
Creator: Baca, A. G.; Sherwin, M. E.; Zolper, J. C.; Shul, R. J.; Briggs, R. D.; Heise, J. A. et al.

A 1.8 K test facility for superconducting RF cavities

Description: To demonstrate the feasibility of superconducting RF technology for a high energy e{sup +}/e{sup {minus}} collider, a research and development program has begun with collaborators from Europe, Asia, and North America. The immediate goal of the R&D program is to build and operate a 50 meter-long linac at DESY with 1.3 GHz superconducting RF cavities at a temperature of 1.8 K - 2.0 K and an accelerating gradient of 15 MV/meter. The refrigeration for the test system at DESY initially will have a capacity of about 100 W at 1.8 K, distributed among three test cryostats. In a second step, refrigeration will be upgraded to 200 W at 1.8 K in order to supply the 50 meter test linac. This paper describes the cryogenics of this test system.
Date: April 1, 1994
Creator: Horlitz, G.; Knopf, U.; Lange, R.; Petersen, B.; Sellmann, D.; Trines, D. et al.

A 3-axis force balanced accelerometer using a single proof-mass

Description: This paper presents a new method for wideband force balancing a proof-mass in multiple axes simultaneously. Capacitive position sense and force feedback are accomplished using the same air-gap capacitors through time multiplexing. Proof of concept is experimentally demonstrated with a single-mass monolithic surface micromachined 3-axis accelerometer.
Date: April 1997
Creator: Lemkin, M.A.; Boser, B.E.; Auslander, D. & Smith, J.

3-dimensional wells and tunnels for finite element grids

Description: Modeling fluid, vapor, and air injection and extraction from wells poses a number of problems. The length scale of well bores is centimeters, the region of high pressure gradient may be tens of meters and the reservoir may be tens of kilometers. Furthermore, accurate representation of the path of a deviated well can be difficult. Incorporating the physics of injection and extraction can be made easier and more accurate with automated grid generation tools that incorporate wells as part of a background mesh that represents the reservoir. GEOMESH is a modeling tool developed for automating finite element grid generation. This tool maintains the geometric integrity of the geologic framework and produces optimal (Delaunay) tetrahedral grids. GEOMESH creates a 3D well as hexagonal segments formed along the path of the well. This well structure is tetrahedralized into a Delaunay mesh and then embedded into a background mesh. The well structure can be radially or vertically refined and each well layer is assigned a material property or can take on the material properties of the surrounding stratigraphy. The resulting embedded well can then be used by unstructured finite element models for gas and fluid flow in the vicinity of wells or tunnels. This 3D well representation allows the study of the free- surface of the well and surrounding stratigraphy. It reduces possible grid orientation effects, and allows better correlation between well sample data and the geologic model. The well grids also allow improved visualization for well and tunnel model analysis. 3D observation of the grids helps qualitative interpretation and can reveal features not apparent in fewer dimensions.
Date: April 1, 1996
Creator: Cherry, T.A.; Gable, C.W. & Trease, H.

4. International reservoir characterization technical conference

Description: This volume contains the Proceedings of the Fourth International Reservoir Characterization Technical Conference held March 2-4, 1997 in Houston, Texas. The theme for the conference was Advances in Reservoir Characterization for Effective Reservoir Management. On March 2, 1997, the DOE Class Workshop kicked off with tutorials by Dr. Steve Begg (BP Exploration) and Dr. Ganesh Thakur (Chevron). Tutorial presentations are not included in these Proceedings but may be available from the authors. The conference consisted of the following topics: data acquisition; reservoir modeling; scaling reservoir properties; and managing uncertainty. Selected papers have been processed separately for inclusion in the Energy Science and Technology database.
Date: April 1997

A 5-cm dipole for the SSC-DE-1

Description: A 5cm SSC superconducting dipole that develops 6.6 tesla at 5790 A is proposed. The two layer magnet has 12% more transfer function than the present design as a result of using thin collars and close in'' iron. The thin collars provide precise positioning of the coils; they also provide minimum prestress (perhaps 2000 psi) as aid for magnet assembly. A welded skin around the iron provides the final prestress and shapes and the coil geometry. A prestressed aluminum bar placed between the vertically split iron yokes provides precise control of the gap between yokes halves and is designed to allow gap to close tightly during cooldown so that there is no decrease of prestress. In order to reduce the effect of iron saturation on the field multipoles the iron ID has been optimized to an elliptical shape. The coil inner layer is a 30 strand cable with 1.3:1 cu/sc. The outer layer is a 36 strand cable wit 1.8:1 cu/sc. At the operating field of 6.6 tesla the current density in the copper is 666 A/mm{sup 2} and 760 A/mm{sup 2} in the inner and outer layers respectively. The magnet short sample performance is limited by the inner layer. Operating at 4.35 K the maximum current and central field are 6896 A and 7.95 tesla. The calculated operating short sample temperature at 6.6 tesla and 5798 A is 5.17 K (0.82 K temperature margin). The magnet stored energy is 100.0 (KJ/m) at the 5790 A operating current. A mechanically similar 5cm bore two layer dipole for the cable test facility (D-16B-1) has been recently built and tested. The magnet had no collars and the iron was placed directly on the coil OD. The magnet's first quench was at 7 tesla with 6000 A and it reached 7.6 tesla at ...
Date: April 30, 1990
Creator: Caspi, S.

A 40 GByte/s read-out system for GEM

Description: The preliminary design of the read-out system for the GEM (Gammas, Electrons, Muons) detector at the Superconducting Super Collider is presented. The system reads all digitized data from the detector data sources at a Level 1 trigger rate of up to 100 kHz. A total read-out bandwidth of 40 GBytes/s is available. Data are stored in buffers that are accessible for further event filtering by an on-line, processor farm. Data are transported to the farm only as they are needed by the higher-level trigger algorithms, leading to a reduced bandwidth requirement in the Data Acquisition System.
Date: April 1994
Creator: Bowden, M.; Carrel, J.; Dorenbosch, J. & Kapoor, V.

45-Day safety screen results for Tank 241-BY-103, auger samples 95-AUG-012 and 95-AUG-013

Description: Two auger samples from tank 241-BY-103 (BY-103) were received by the 222-S Laboratories and underwent safety screening analysis, consisting of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and total alpha activity. Analytical results for the TGA analyses for both samples were less than the safety screening notification limit. Since notification is made if the sample is analyzed at less than 17% water, notification was made on April 20, 1995. Although the sample results were below this limit, no secondary analyses were required or performed. Included in this report are the primary safety screening results obtained from the analyses and copies of all DSC and TGA raw data scans as requested per the TCP. Photographs of the auger samples were taken during extrusion and, although not included in this report, are available. Tank BY-103 is on the ferrocyanide Watch List.
Date: April 21, 1995
Creator: Schreiber, R.D.

94-A13 Native American Initiative Short Course Management Plan

Description: A training program conducted in Bartlesville by BDM-Oklahoma technical staff, which included geologists, geophysicists, exploration and drilling specialists, and environmental policy experts. The proposed training schedule offered four courses per year and included those coursed identified by the tribes in the survey. The training program was outlined for members of Native American Tribes whose lands have oil and gas resources. The proposed program contributed to meeting the goals of the U.S. Department of Energy's (DOE) Domestic Oil and Gas Initiative to help Native American tribes become more self-sufficient in developing and managing their resources through training in cost-effective, improved technologies for hydrocarbon production that will meet environmental regulations. The training program outlined was for adult tribal representatives who are responsible for managing tribal mineral holdings or setting policy, or who work in the oil and gas industry. The course content is in response to a survey that was developed by BDM-Oklahoma and sent in the Spring of 1995 to 26 tribal agencies identified through previous contact with DOE. Tribes were asked to indicate course content needs, levels, preferred time of year, and location. Six tribes responded with specific recommendations and needs. These tribes, were the Creek, Pueblo, Cherokee, St. Regis Mohawk, Northern Arapho, and Ute Mountain Ute.
Date: April 27, 1999
Creator: Carroll, Herbert B.; Johnson, William I. & Kokesh, Judith H.

100-D Area In Situ Redox Treatability Test for Chromate-Contaminated Groundwater: FY 1998 Year-End Report

Description: A treatability test was conducted for the In Situ Redox Manipulation (ISRM) technology at the US Department of Energy's Hanford, Washington 100D Area. The target contaminant was dissolved chromate [Cr(VI)] in groundwater. The ISRM technology involves creating a permeable subsurface treatment zone to reduce mobile chromate in groundwater to an insoluble form. The ISRM permeable treatment zone is created by reducing ferric iron [Fe(III)] to ferrous iron [Fe(II)] within the aquifer sediments. This is accomplished by injecting aqueous sodium dithionite into the aquifer and withdrawing the reaction products. The goal of the treatability test was to create a linear ISRM barrier by injecting sodium dithionite into five wells. Well installation and site characterization activities began in the spring of 1997. The first dithionite injection took place in September 1997. The results of this first injection were monitored through the spring of 1998; the remaining four dithionite injections were carried out in May through July of 1998. These five injections created a reduced zone in the Hanford unconfined aquifer 150 feet in length (perpendicular to groundwater flow) by 50 feet wide. The reduced zone extended over the thickness of the unconfined zone, which is approximately 15 feet. Analysis of recent groundwater sampling events shows that the concentrations of chromate [Cr(VI)] in groundwater in the reduced zone have been decreased from starting concentrations of approximately 900 ppb to below analytical detection limits (<7 ppb). Chromate concentrations are also declining in some downgradient monitoring wells. Laboratory analysis of iron in the soil indicates that the barrier should remain in place for approximately 20 to 25 years. These measurements will be confirmed by analysis of sediment cores in FY 1999.
Date: April 15, 1999
Creator: Williams, M. D.; Vermeul, V. R.; Szecsody, J. E.; Fruchter, J. S. & Cole, C. R.

100-D Ponds groundwater quality assessment

Description: The 100-D Ponds facility is regulated under the Resource Conservation and Recovery Act of 1976. The pH of groundwater in a downgradient well is statistically different than local background, triggering an assessment of groundwater contamination under 40 CFR 265.93. Results of a similar assessment, conducted in 1993, show that the elevated pH is caused by the presence of alkaline ash sediments beneath the ponds, which are not part of the RCRA unit. The 100-D Ponds should remain in indicator evaluation monitoring.
Date: April 11, 1996
Creator: Hartman, M. J.

100-FR-3 groundwater/soil gas supplemental limited field investigation report

Description: In 1993, a Limited Field Investigation (LFI) was conducted for the 100-FR-3 Operable Unit which identified trichloroethylene (TCE) as a contaminant of potential concern (COPC) (DOE-RL 1994). In groundwater samples collected for the LFI, TCE was detected in well 199-177-1 at a concentration exceeding the U.S. Environmental Protection Agency (EPA) maximum contaminant level (5 {mu}g/L) and Washington State groundwater criteria (3 {mu}g/L). With the concurrence of the EPA and the Washington State Department of Ecology (Ecology), a supplemental LFI was conducted to determine the extent and potential source of TCE groundwater contamination associated with the 100-FR-3 Operable Unit. This report summarizes the activities and results of the groundwater/soil gas supplemental LFI for the 100-FR-3 Operable Unit. The primary objective of this investigation was to assess the lateral distribution of TCE in shallow (3 to 5 ft below the water table) groundwater associated with the 100-FR-3 Operable Unit. The second objective was to assess soil gas (3 to 5 concentrations in the study area in an attempt to identify potential sources of TCE and develop a correlation between soil gas and groundwater concentrations). Finally, the third objective of the investigation was to refine the site conceptual model.
Date: April 1, 1996

100 years of elementary particles [Beam Line, vol. 27, issue 1, Spring 1997]

Description: This issue of Beam Line commemorates the 100th anniversary of the April 30, 1897 report of the discovery of the electron by J.J. Thomson and the ensuing discovery of other subatomic particles. In the first three articles, theorists Abraham Pais, Steven Weinberg, and Chris Quigg provide their perspectives on the discoveries of elementary particles as well as the implications and future directions resulting from these discoveries. In the following three articles, Michael Riordan, Wolfgang Panofsky, and Virginia Trimble apply our knowledge about elementary particles to high-energy research, electronics technology, and understanding the origin and evolution of our Universe.
Date: April 1, 1997
Creator: Pais, Abraham; Weinberg, Steven; Quigg, Chris; Riordan, Michael; Panofsky, Wolfgang K.H. & Trimble, Virginia

105-DR Large Sodium Fire Facility closure activities evaluation report

Description: This report evaluates the closure activities at the 105-DR Large Sodium Fire Facility. The closure activities discussed include: the closure activities for the structures, equipment, soil, and gravel scrubber; decontamination methods; materials made available for recycling or reuse; and waste management. The evaluation compares these activities to the regulatory requirements and closure plan requirements. The report concludes that the areas identified in the closure plan can be clean closed.
Date: April 22, 1996
Creator: Adler, J. G.

105-DR Large Sodium Fire Facility closure activities evaluation report

Description: This report evaluates the closure activities at the 105-DR Large Sodium Fire Facility. The evaluation compares these activities to the regulatory requirements and closure plan requirements. The report concludes that the areas identified in the closure plan can be clean closed. This report summarizes and evaluates the closure activities performed in support of partial closure of the 105-DR Large Sodium Fire Facility (LSFF). This evaluation will be used in assessing the condition of the 105-DR LSFF for the purpose of meeting the partial clean closure conditions described in the 105-DR Large Sodium Fire Facility Closure Plan (DOE-RL 1995). Based on the evaluation of the decontamination activities, sampling activities, and sample data, it is has been determined that the partial clean closure conditions for the 105-DR LSFF have been met.
Date: April 11, 1996
Creator: Adler, J. G.

(129)Xe NMR of Mesoporous Silicas

Description: The porosities of three mesoporous silica materials were characterized with {sup 129}Xe NMR spectroscopy. The materials were synthesized by a sol-gel process with r = 0, 25, and 70% methanol by weight in an aqueous cetyltrimethylammonium bromide solution. Temperature dependent chemical shifts and spin lattice relaxation times reveal that xenon does not penetrate the pores of the largely disordered (r= 70%) silica. For both r = 0 and 25%, temperature dependent resonances corresponding to physisorbed xenon were observed. An additional resonance for the r = 25% sample was attributed to xenon between the disordered cylindrical pores. 2D NMR exchange experiments corroborate the spin lattice relaxation data which show that xenon is in rapid exchange between the adsorbed and the gas phase.
Date: April 23, 1999
Creator: Anderson, M.T.; Asink, R.A.; Kneller, J.M. & Pietrass, T.

183-H Basin Mixed Waste Analysis and Testing Report

Description: The purpose of this sampling and analysis report is to provide data necessary to support treatment and disposal options for the low-level mixed waste from the 183-H solar evaporation ponds. In 1973, four of the 16 flocculation and sedimentation basins were designated for use as solar evaporation basins to provide waste reduction by natural evaporation of liquid chemical wastes from the 300 Area fuel fabrication facilities. The primary purpose of this effort is to gather chemical and bulk property data for the waste in the drums/boxes of sediment removed from the basin at Central Waste Complex.
Date: April 1, 1995

200-BP-5 operable unit treatability test report

Description: The 200-BP-5 Operable Unit was established in response to recommendations presented in the 200 East Groundwater Aggregate Area Management Study Report (AAMSR) (DOE-RL 1993a). Recognizing different approaches to remediation, the groundwater AAMSR recommended separating groundwater from source and vadose zone operable units and subdividing 200 East Area groundwater into two operable units. The division between the 200-BP-5 and 200-PO-1 Operable Units was based principally on source operable unit boundaries and distribution of groundwater plumes derived from either B Plant or Plutonium/Uranium Extraction (PUREX) Plant liquid waste disposal sites.
Date: April 1, 1996

200-UP-2 operable unit radiological surveys

Description: This report summarizes and documents the results of the radiological surveys conducted from August 17 through December 16, 1993 over a partial area of the 200-UP-2 Operable Unit, 200-W Area, Hanford Site, Richland, Washington. In addition, this report explains the survey methodology of the Mobile Surface Contamination Monitor 11 (MSCM-II) and the Ultra Sonic Ranging And Data System (USRADS). The radiological survey of the 200-UP-2 Operable Unit was conducted by the Site Investigative Surveys/Environmental Restoration Health Physics Organization of the Westinghouse Hanford Company. The survey methodology for the majority of area was based on utilization of the MSCM-II or the USRADS for automated recording of the gross beta/gamma radiation levels at or near six (6) inches from the surface soil.
Date: April 30, 1994
Creator: Wendling, M. A.

222-S laboratory quality assurance plan

Description: This document provides quality assurance guidelines and quality control requirements for analytical services. This document is designed on the basis of Hanford Analytical Services Quality Assurance Plan (HASQAP) technical guidelines and is used for governing 222-S and 222-SA analytical and quality control activities. The 222-S Laboratory provides analytical services to various clients including, but not limited to, waste characterization for the Tank Waste Remediation Systems (TWRS), waste characterization for regulatory waste treatment, storage, and disposal (TSD), regulatory compliance samples, radiation screening, process samples, and TPA samples. A graded approach is applied on the level of sample custody, QC, data verification, and data reporting to meet the specific needs of the client.
Date: April 1, 1995
Creator: Meznarich, H.K.

242-A Evaporator Waste Analysis Plan. Revision 5

Description: This Waste Analysis Plan (WAP) provides the plan for obtaining information needed for proper waste handling and processing in the 242-A Evaporator (Evaporator) located on the Hanford Site. In particular it addresses analysis necessary to manage the waste according to Washington Administrative Code (WAC) 173-303 and Parts 264 and 265 of the Code of Federal Regulations (CFR). Regulatory and safety issues are addressed by establishing boundary conditions for waste received and treated at the 242-A Evaporator. The boundary conditions are set by establishing limits for items such as potential exothermic reactions, waste compatibility, and control of vessel vent organic emissions. Boundary conditions are also set for operational considerations and to ensure waste acceptance at receiving facilities. The issues that are addressed in this plan include prevention of exotherms in the waste, waste compatibility, and vessel vent emissions. Samples from the other streams associated with the Evaporator are taken as required by Process Control Plans but are excluded from this plan because either the streams do not contain dangerous waste or the analyses are not required by WAC 173-303-300.
Date: April 13, 1995
Creator: Basra, T.S.

296-B-10 stack monitoring and sampling system annual system assessment report

Description: B Plant Administration Manual, requires an annual system assessment to evaluate and report the present condition of the sampling and monitoring system associated with stack 296-B-10 at B Plant. The ventilation system of WESF (Waste Encapsulation and Storage Facility) is designed to provide airflow patterns so that air movement throughout the building is from areas of lesser radioactivity to areas of greater radioactivity. All potentially contaminated areas are maintained at a negative pressure with respect to the atmosphere so that air flows into the building at all times. The exhaust discharging through the 296-B-10 stack is continuously monitored and sampled using a sampling and monitoring probe assembly located approximately 17.4 meters (57 feet) above the base of the stack. The probe assembly consists of 5 nozzles for the sampling probe and 2 nozzles to monitor the flow. The sampling and monitoring system associated with Stack 296-B-10 is functional and performing satisfactorily.
Date: April 26, 1995
Creator: Ridge, T.M.