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Effectiveness of various protective coverings on magnesium fins at Mach number 2.0 and stagnation temperatures up to 3,600 degrees R

Description: Report presenting eight thin magnesium fins, seven with the leading edges swept back 17 degrees and one with the leading edge swept back 45 degrees, in the preflight high-temperature jet. The investigation was made to determine the effectiveness of various protective coverings designed to alleviate aerodynamic-heating effects and intended for application on the first stage of rocket-propelled multistage hypersonic models.
Date: January 9, 1958
Creator: Bland, William M., Jr.
Partner: UNT Libraries Government Documents Department

Textile

Description: Textile. Rectangular panel of handwoven cotton/wool, with fringed ends. Mexican weaving, in the Saltillo style, done in reds, blacks, blues, greens, and white. Inlay designs with central diamond shape formed of chevrons and diamonds, width-wise stripes of gradated colors, and bands with short trapezoidal gradated bars of color.
Date: 1965~
Partner: UNT College of Visual Arts + Design

Blue Tide

Description: This queen sized bedspread, screen printed on cotton velvet, was created while Spear studied at Cranbrook Art Academy in Bloomfield Hills, Michigan. The bedspread gradates from purples to blues with long wave shapes in a pale yellow gold color.
Date: 1978
Creator: Spear, Shigeko
Partner: UNT College of Visual Arts + Design

Large-Scale Field Study of Landfill Covers at Sandia National Laboratories

Description: A large-scale field demonstration comparing final landfill cover designs has been constructed and is currently being monitored at Sandia National Laboratories in Albuquerque, New Mexico. Two conventional designs (a RCRA Subtitle `D' Soil Cover and a RCRA Subtitle `C' Compacted Clay Cover) were constructed side-by-side with four alternative cover test plots designed for dry environments. The demonstration is intended to evaluate the various cover designs based on their respective water balance performance, ease and reliability of construction, and cost. This paper presents an overview of the ongoing demonstration.
Date: September 1, 1998
Creator: Dwyer, S.F.
Partner: UNT Libraries Government Documents Department

A one piece wall box for space electronics

Description: In extraterrestrial applications, satellite payloads have printed circuit modules that are housed in boxes or chassis. The box may be a one piece wall or a segmented wall. These two wall options are compared for function and cost.
Date: May 1, 1995
Creator: Greenwood, W.H.
Partner: UNT Libraries Government Documents Department

Experimental Measurement of the Flow Field of Heavy Trucks

Description: Flat flaps that enclose the trailer base on the sides and top are known to reduce truck drag and reduce fuel consumption. Such flapped-truck geometries have been studied in laboratory wind tunnels and in field tests. A recent review of wind tunnel data for a variety of truck geometries and flow Reynolds numbers show roughly similar values of peak drag reduction, but differ in the determination of the optimum flap angle. Optimum angles lie in the range 12 degrees-20 degrees, and may be sensitive to Reynolds number and truck geometry. The present field test is undertaken to provide additional estimates of the magnitude of the savings to be expected on a typical truck for five flap angles 10, 13, 16, 19, and 22 degrees. The flaps are constructed from a fiberglass-epoxy-matrix material and are one-quarter of the base width in length (about 61 cm, or 2 feet). They are attached along the rear door hinge lines on either side of the trailer, so that no gap appears at the joint between the flap and the side of the trailer The flap angle is adjusted by means of two aluminum supports. The present test is performed on the NASA Crows Landing Flight Facility at the northern end of the San Joaquin valley in California. The main runway is approximately 2400 meters in length, and is aligned approximately in a north-south direction The test procedure is to make a series of runs starting at either end of the runway. All runs are initiated under computer control to accelerate the truck to a target speed of 60 mph (96 6 km/hr), to proceed at the target speed for a fixed distance, and to decelerate at the far end of the runway. During a run, the broadcast fuel rate, the engine rpm, forward speed, ...
Date: May 31, 2005
Creator: Browand, Fred & Radovich, Charles
Partner: UNT Libraries Government Documents Department

Cost comparisons of alternative landfill final covers

Description: A large-scale field demonstration comparing and contrasting final landfill cover designs has been constructed and is currently being monitored. Four alternative cover designs and two conventional designs (a RCRA Subtitle ``D`` Soil Cover and a RCRA Subtitle ``C`` Compacted Clay Cover) were constructed of uniform size, side-by-side. The demonstration is intended to evaluate the various cover designs based on their respective water balance performance, ease and reliability of construction, and cost. This paper provides an overview of the construction costs of each cover design.
Date: February 1, 1997
Creator: Dwyer, S.F.
Partner: UNT Libraries Government Documents Department

TDR calibration for the alternative landfill cover demonstration (ALCD)

Description: The Alternative Landfill Cover Demonstration is a large scale field test that compares the performance of various landfill cover designs in dry environments. An important component of the comparison is the change in the moisture content of the soils throughout the different cover test plots. Time Domain Reflectometry (TDR) is the primary method for the measurement of the volumetric moisture content. Each of the covers is composed of layers of varying types and densities of soils. The probes are therefore calibrated to calculate the volumetric moisture content in each of the different soils in order to gain the optimum performance of the TDR system. The demonstration plots are constructed in two phases; a different probe is used in each phase. The probe that is used in Phase 1 is calibrated for the following soils: compacted native soil, uncompacted native soil, compacted native soil mixed with 6% sodium bentonite by weight, and sand. The probe that is used in Phase 2 is calibrated for the following soils: compacted native soil, uncompacted native soil, and sand. In addition, the probes are calibrated for the varying cable lengths of the TDR probes. The resulting empirically derived equations allow for the calculation of in-situ volumetric moisture content of all of the varying soils throughout the cover test plots in the demonstration.
Date: September 1, 1997
Creator: Lopez, J.; Dwyer, S.F. & Swanson, J.N.
Partner: UNT Libraries Government Documents Department

Title I conceptual design for Pit 6 landfill closure at Lawrence Livermore National Laboratory Site 300

Description: The objective of this design project is to evaluate and prepare design and construction documents for a closure cover cap for the Pit 6 Landfill located at Lawrence Livermore National Laboratory Site 300. This submittal constitutes the Title I Design (Conceptual Design) for the closure cover of the Pit 6 Landfill. A Title I Design is generally 30 percent of the design effort. Title H Design takes the design to 100 percent complete. Comments and edits to this Title I Design will be addressed in the Title II design submittal. Contents of this report are as follows: project background; design issues and engineering approach; design drawings; calculation packages; construction specifications outline; and construction quality assurance plan outline.
Date: August 1, 1996
Creator: MacDonnell, B.A. & Obenauf, K.S.
Partner: UNT Libraries Government Documents Department

Universal Branched Coverings

Description: In this paper, the study of k-fold branched coverings for which the branch set is a stratified set is considered. First of all, the existence of universal k-fold branched coverings over CW-complexes with stratified branch set is proved using Brown's Representability Theorem. Next, an explicit construction of universal k-fold branched coverings over manifolds is given. Finally, some homotopy and homology groups are computed for some specific examples of Universal k-fold branched coverings.
Date: May 1993
Creator: Tejada, D├ębora
Partner: UNT Libraries

Microflora Found in a Selected Group of Food Products Enclosed in a Protective Wrapper

Description: The purposes of this study are, first, to determine relative numbers and predominant types of bacterial organisms in the various food products studied; second, to evaluate the efficiency of the paper coverings of these foods; and third, to determine whether these products are potential sources of food poisoning.
Date: 1949
Creator: Ogden, William H.
Partner: UNT Libraries

Post-Closure Inspection Report for Corrective Action Unit 90: Area 2 Bitcutter Containment, Nevada Test Site, Nevada for the Period July 2005- June 2006

Description: This annual report covers the period of July 2005 to June 2006 and consists of copies of the inspection checklists, maintenance and repair records (if any), photographs, and recommendations and conclusions. The semiannual inspections for CAU 90 were performed on December 12, 2005, and June 20, 2006. The December inspection indicated continued integrity of the unit. The fencing, signs, and cover were in excellent condition. No further inspections or actions are necessary other than continuing the semiannual inspections. The June inspection also indicated continued integrity of the waste unit cover. No vegetation was noted on the cover. Some small animal burrows were backfilled during the time of the site inspection and will be watched during future inspections. The fencing, signs, and gate were in excellent condition.
Date: August 1, 2006
Partner: UNT Libraries Government Documents Department

CNS 1-13G cask lid support work plan

Description: This work plan covers fabrication and load testing of one Chem-Nuclear Systems (CNS) 1-13G Cask lid Support Frame, per the attached drawing. The support frame is considered to be developmental equipment and as such may be fabricated in accordance with the engineering requirements and responsibilities identified in WHC-CM-6-1, Standard Engineering Practices, EP-2.4 Development Control Requirements. A final acceptance and load test is required by February 24, 1995. WHC will provide a released as-built drawing of the support frame by February 22, 1995 to allow final acceptance to occur prior to the completion date.
Date: February 17, 1995
Creator: Crow, S.R.
Partner: UNT Libraries Government Documents Department

Final closure cover for a Hanford radioactive mixed waste disposal facility

Description: This study provides a preliminary design for a RCRA mixed waste landfill final closure cover. The cover design was developed by a senior class design team from Seattle University. The design incorporates a layered design of indigenous soils and geosynthetics in a layered system to meet final closure cover requirements for a landfill as imposed by the Washington Administrative Code WAC-173-303 implementation of the Resource Conservation and Recovery Act.
Date: February 6, 1996
Creator: Johnson, K. D.
Partner: UNT Libraries Government Documents Department

Control of water infiltration into near surface low-level waste disposal units. Final report on field experiments at a humid region site, Beltsville, Maryland

Description: This study`s objective was to assess means for controlling water infiltration through waste disposal unit covers in humid regions. Experimental work was carried out in large-scale lysimeters 21.34 m x 13.72 m x 3.05 m (70 ft x 45 ft x 10 ft) at Beltsville, Maryland. Results of the assessment are applicable to disposal of low-level radioactive waste (LLW), uranium mill tailings, hazardous waste, and sanitary landfills. Three kinds of waste disposal unit covers or barriers to water infiltration were investigated: (1) resistive layer barrier, (2) conductive layer barrier, and (3) bioengineering management.
Date: September 1, 1997
Creator: Schulz, R.K.; Ridky, R.W. & O`Donnell, E.
Partner: UNT Libraries Government Documents Department

Innovative Composite Wall System for Sheathing Masonry Walls

Description: Existing Housing - Much of the older multifamily housing stock in the United States includes units in structures with uninsulated masonry walls. Included in this stock are two- and three-story walk-up apartments, larger apartment complexes, and public housing (both high- rise and townhouse). This older multifamily housing has seen years of heavy use that may have left the plaster wall marred or damaged. Long- term building settlement or movement may have cracked the plaster, sometimes severely. Moisture from invented kitchens and baths may have caused condensation on uninsulated exterior walls. At best this condensation has left stains on the paint or wallpaper. At worst it has supported mold and mildew growth, fouling the air and creating unhealthy living conditions. Deteriorating plaster and flaking paint also result from wet walls. The presence of flaking, lead-based paint in older (pre-1978) housing is a major public health concern. Children can suffer permanent mental handicaps and psychological disorders if they are subjected to elevated levels of lead, while adults can suffer hypertension and other maladies. Studies have found that, in some urban communities with older housing stocks, over 35% of children tested have elevated blood lead levels (Hastings, et al.: 1997). Nationally, nearly 22% of black, non-hispanic children living in pre-1946 housing were found to have elevated levels of lead in their blood (MWWR Article: February 21,1997). The deterioration of many of these walls is to the point that lead can freely enter the living space.
Date: September 25, 1997
Creator: Wendt, Robert L. & Cavallo, James
Partner: UNT Libraries Government Documents Department

Thermal management of batteries using a Variable-Conductance Insulation (VCI) enclosure

Description: Proper thermal management is important for optimum performance and durability of most electric-vehicle batteries. For high-temperature cells such as sodium/sulphur, a very efficient and responsive thermal control system is essential. Heat must be removed during exothermic periods and retained when the batteries are not in use. Current thermal management approaches rely on passive insulation enclosures with active cooling loops that penetrate the enclosure. This paper presents the design, analysis, and testing of an enclosure with variable conductance insulation (VCI). VCI uses a hydride with an integral electric resistance heater to expel and retrieve a small amount of hydrogen gas into a vacuum space. By controlling the amount of hydrogen gas, the thermal conductance can be varied by more than 100:1, enabling the cooling loop (cold plate) to be mounted on the enclosure exterior. By not penetrating the battery enclosure, the cooling system is simpler and more reliable. Also, heat can be retained more effectively when desired. For high temperatures, radiation shields within the vacuum space are required. Ceramic spacers are used to maintain separation of the steel enclosure materials against atmospheric loading. Ceramic-to-ceramic thermal contact resistance within the spacer assembly minimizes thermal conductance. Two full-scale (0.8-m {times} 0.9-m {times} 0.3-m) prototypes were designed, built, and tested under high-temperature 200{degrees}-350{degrees}C battery conditions. With an internal temperature of 330{degrees}C (and 20{degrees}C ambient), the measured total-enclosure minimum heat loss was 80 watts (excluding wire pass-through losses). The maximum heat rejection was 4100 watts. The insulation can be switched from minimum to maximum conductance (hydrogen pressure from 2.0 {times} 10{sup -3} to 8 torr) in 3 minutes. Switching from maximum to minimum conductance was longer (16 minutes), but still satisfactory because of the large thermal mass of the battery.
Date: May 1, 1995
Creator: Burch, S.D.; Parish, R.C. & Keyser, M.A.
Partner: UNT Libraries Government Documents Department

Alternative Site Technology Deployment-Monitoring System for the U-3ax/bl Disposal Unit at the Nevada Test Site

Description: In December 2000, a performance monitoring facility was constructed adjacent to the U-3ax/bl mixed waste disposal unit at the Nevada Test Site (NTS). Recent studies conducted in the arid southwestern United States suggest that a vegetated monolayer evapotranspiration (ET) closure cover may be more effective at isolating waste than traditional Resource Conservation and Recovery Act (RCRA) multi-layered designs. The monitoring system deployed next to the U-3ax/bl disposal unit consists of eight drainage lysimeters with three surface treatments: two are left bare; two are revegetated with native species; two are being allowed to revegetate with invader species; and two are reserved for future studies. Soil used in each lysimeter is native alluvium taken from the same location as the soil used for the cover material on U-3ax/bl. The lysimeters were constructed so that any drainage to the bottom can be collected and measured. To provide a detailed evaluation of the cover performance, an ar ray of 16 sensors was installed in each lysimeter to measure soil water content, soil water potential, and soil temperature. Revegetation of the U-3ax/bl closure cover establishes a stable plant community that maximizes water loss through transpiration while at the same time, reduces water and wind erosion and ultimately restores the disposal unit to its surrounding Great Basin Desert environment.
Date: February 1, 2001
Creator: Dixon, J.M.; Levitt, D.G. & Rawlinson, S.E.
Partner: UNT Libraries Government Documents Department

Engineered covers for mud pit closures Central Nevada Test Area, Nevada

Description: Two abandoned drilling mud pits impacted with petroleum hydrocarbons were determined to require closure action at the Central Nevada Test Area. The UC-4 Mud Pit C is approximately 0.12 hectares (0.3 acres) and 1.2 meters (4 feet) in depth. The UC-1 Central Mud Pit (CMP) is approximately 1.54 hectares (3.8 acres) and 2.4 meters (8 feet) in depth. Both mud pits contain bentonite drilling muds with a thin dry crust, low shear strength, low permeability, and high moisture content. The following closure methodologies were evaluated: stabilization by mixing/injection with soil, fly ash, and lime; excavation and disposal; on-site drying; thermal destruction; wick drains; administrative closure (postings and land-use restrictions); and engineered covers. Based upon regulatory closure criteria, implementation, and cost considerations, the selected remedial alternative was the construction of an engineered cover. A multilayered cover with a geo-grid and geo-synthetic clay liner (GCL) was designed and constructed over the UC-4 Mud Pit C to evaluate the constructability and applicability of the design for the CMP cover. The geo-grid provided structural strength for equipment and material loads during cover construction, and the GCL was used as a moisture infiltration barrier. The design was determined to be constructable and applicable. To reduce project costs for the CMP cover, a vegetative cover was designed with drainage toward the center of the cover rather than the perimeter. The vegetative cover with the internal drainage design resulted in a fill volume reduction of approximately 63 percent compared to the multilayered cover design with a GCL.
Date: June 30, 2000
Creator: Madsen, D. D.
Partner: UNT Libraries Government Documents Department