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Effect of Temperature on Dynamic Modulus of Elasticity of Some Structural Alloys

Description: Note presenting the effect of temperature on Young's modulus of elasticity as determined for 2024-T3 and 7075-T6 aluminum alloys, AZ31A-0 magnesium alloy, RS-120 titanium alloy, and type 303 stainless steel by flexural vibration tests of beam specimens at temperatures from room temperature to 900 degrees Fahrenheit. The test frequencies were varied from 40 to 550 cycles per second.
Date: August 1958
Creator: Vosteen, Louis F.
Partner: UNT Libraries Government Documents Department

Effect of Temperature on Viscosity of Slurries of Boron and Magnesium in JP-5 Fuel

Description: Memorandum presenting the viscosities of slurries containing 50 to 65 percent by weight of boron in JP-5 fuel at temperatures from 30 to 80 degrees Celsius and of slurries containing 50 percent by weight of magnesium in JP-5 fuel from -40 to 80 degrees Celsius. Plastic viscosities of the boron slurries decreased consistently with an increase in temperature. Results regarding boron slurries and magnesium slurries are provided.
Date: July 18, 1955
Creator: Hipsher, Harold F.
Partner: UNT Libraries Government Documents Department

Effect of temperature on performance of several ejector configurations

Description: Report presenting an investigation to determine the effect of the primary-jet temperature on the performance of several ejector configurations. The performance of ejectors expressed in terms of the ratio of weight of secondary air flow to primary air flow was found to be affected by temperature in two ways.
Date: June 13, 1949
Creator: Wilsted, H. D.; Huddleston, S. C. & Ellis, C. W.
Partner: UNT Libraries Government Documents Department

Effect of ambient-temperature variation on the matching requirements of inlet-engine combinations at supersonic speeds

Description: Report presenting an analysis of the effect of ambient temperature on the matching requirements of inlet-engine combinations for two typical turbojet engines up to Mach number 3.5. The results indicated that if a bypass or movable compression surface are to be used for efficient inlet-engine matching, the inlet should be sized for the lowest ambient temperature to be encountered.
Date: January 1957
Creator: Perchonok, Eugene & Hearth, Donald P.
Partner: UNT Libraries Government Documents Department

The Effect of Temperature on Sheet Metals for Airplane Firewalls

Description: Note presenting tests conducted on 5 uncoated steels and 20 steels with various coatings to determine the effect of temperature on the tensile properties and surface characteristics of the metals. The metals were subjected to furnace-heating tests over a range of temperatures for various times and to flame-impingement and airplane-fire tests. Results regarding metals without surface coatings, low carbon steels with surface coatings, and discussion of comparative behaviors regarding the different surface coatings are provided.
Date: December 1944
Creator: Mutchler, Willard
Partner: UNT Libraries Government Documents Department

Preliminary Free-Jet Performance of XRJ43-MA-3 Flight-Weight Ram-Jet Engine at Mach Numbers of 2.35, 2.50, and 2.70

Description: From Summary: "The performance of the XRJ43-MA-3 flight-weight ram-jet engine has been investigated in a free-jet facility as part of the development program for the "Bomarc," ram-jet powered, interceptor-type missile. The engine performance was obtained at Mach numbers of 2.35, 2.50, and 2.70, altitudes from 50,000 to 75,000 feet, and Miami hot day and cold day inlet temperatures at an angle of attack of +4 deg. At each flight condition investigated, the engine control set an inner-ring fuel flow which was held constant as outer-ring fuel flow was varied."
Date: November 18, 1955
Creator: McAulay, John E. & Prince, William R.
Partner: UNT Libraries Government Documents Department

Drumming Behavior of Selected Nearctic Stoneflies (Plecoptera)

Description: Drumming was recorded for 11 of 13 Nearctic stonefly species, representing 4 families. Both male and female signals were obtained from 5 species, and were either 2-way or 3-way communications. Signals were species-specific; those of males and females varied from 3-39 and 1-14 beats/ signal, respectively. Duration of male signals varied from 105-8,016 ms; those of females, except Perlinella drymo (1 beat), varied from 402-1318 ms. Signals among related taxa showed greatest similarities. Duration of male signals of Perlinella drymo became progressively shorter at each of 4 temperatures from 7-29 0C. Females of Perlinella drymo would only repeatedly answer male signals recorded at near their own temperature, and would not repeatedly answer recorded male signals of 8 other species.
Date: August 1976
Creator: Zeigler, David D.
Partner: UNT Libraries

Observations of borehole deformation modulus values before and after extensive heating of a granitic rock mass

Description: An extensive campaign of in situ deformation modulus measurements was recently completed using a standard NX borehole jack. These results were obtained in a granite intrusive where spent nuclear-fuel assemblies and electrical heaters had raised the rock temperatures 10{sup 0}C to 40{sup 0}C above ambient. We present an analysis of temperature effects based on 41 preheat and 63 post-heat measurements in three boreholes. Using analysis of covariance statistical techniques, we found that the deformation modulus is affected by heat, loading direction, and position within the borehole. The analysis also uncovered a significant interaction between the effects of heating and loading direction. We used 123 measurements from the same boreholes to evaluate the "Draft Standard Guide for Estimating the In Situ Modulus of Rock Masses Using the NX-Borehole Jack" which was recently proposed by Heuze. In particular, we examined the criterion for screening measurements in those cases where contact between the jack platen and the borehole wall was incomplete. We found that the proposed screen appears to operate randomly on the data and is therefore ineffective. 3 figs., 1 tab.
Date: February 1, 1985
Creator: Patrick, W.C.; Yow, J.L. Jr. & Axelrod, M.C.
Partner: UNT Libraries Government Documents Department

The Developmental Physiology of the Zebrafish: Influence of Environment and Cardiovascular Attributes

Description: Temperature effects on the development of the zebrafish embryos and larvae and adults were examined. It was found that the earlier in development a temperature change was performed on an embryo, the more significant the change in survival and/or subsequent development. Thus, viable temperature ranges for zebrafish widened significantly as development proceeded. Adults reared and bred at 25oC produced embryos that were significantly more successful at the lower range of rearing temperatures compared to embryos produced from adults reared at 28oC. The majority of this study focused on the physiological effects of swim training during development in the zebrafish. The earlier in development the zebrafish larvae were trained, the greater the mortality. Trained free swimming larvae had a significantly higher routine oxygen consumption after 11 days of training, and a higher mass specific routine metabolic rate after 8 and 11 days of training. Trained free swimming larvae consumed significantly less oxygen during swimming and were more efficient at locomotion, compared to control larvae. Training enhanced survival during exposure to extreme hypoxia in all age groups. Performance aspects of training were investigated in attempt to quantify training effects and in most cases, trained fish performed significantly better than controls. As blood vessels formed during development, they decreased in cross sectional area from days two to six. It was also shown that the variability in visual stroke volume measurements could be reduced significantly by using a third dimension in the analysis with a more accurate volume equation. Finally, the ontogeny of cardiac control was evaluated. The adrenergic receptors were the first to respond to pharmacological stimulation but were closely followed by cholinergic pharmacological stimulation a few days later. There was a significant cholinergic tone present in day 15 zebrafish larvae which persisted. Although an adrenergic tone was not documented in this study, ...
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Date: August 2001
Creator: Bagatto, Brian
Partner: UNT Libraries

Understanding Thermal Behavior in Lens Processing of Structural Materials

Description: In direct laser metal deposition technologies, such as the Laser (LENS) process, it is important to understand and control the Engineered Net Shaping thermal behavior during fabrication. With this control, components can be reliably fabricated with desired structural material properties. This talk will describe the use of contact and imaging techniques to monitor the thermal signature during LENS processing. Recent results show a direct correlation between thermal history and material properties, where the residual stress magnitude decreases as the laser power, and therefore thermal signature, increases. Development of an understanding of solidification behavior, residual stress, and microstructural evolution with respect to thermal behavior will be discussed.
Date: November 5, 1998
Creator: Ensz, M.T.; Greene, D.L.; Griffith, M.L.; Harwell, L.D.; Hofmeister, W.H.; Nelson, D.V. et al.
Partner: UNT Libraries Government Documents Department

Predicting the thermal response of an encapsulation process

Description: An evaluation of the thermal behavior of an electronic component assembly has indicated a need for increasing the temperature-soak time prior to the electrical testing of potted and unpotted assemblies. The preheat time before encapsulation was found adequate, and the internal mold temperature proved to be within desirable limits during encapsulation. Use of the automatic encapsulation system prevents excessive heat loss during the potting operation and provides a 50% savings in time. A movie showing the encapsulation of a nonfunctional unit in a clear container revealed the formation of three types of voids. Corrective action to eliminate the voids is described.
Date: January 1, 1979
Creator: Richardson, J.H.
Partner: UNT Libraries Government Documents Department

Direct effects of cold shock: bioassays with three Columbia River organisms

Description: Results of studies of the direct effects of cold shock on the pumpkinseed sunfish (representing a warmwater fish), the rainbow trout (representing a coldwater fish), and the common crayfish showed that resistance to cold shock varies between species, is dependent on acclimation temperature, and resistance to temperature declines is dependent on the decline rate. Severe cold shock at a sublethal level is accompanied by disorientation, loss of equilibrium, and immobilization. Pumpkinseed, the warm water species, are most susceptible. Rainbow, the cold water species, are less susceptible; at an acclimation 10$sup 0$C, rainbow survive abrupt shock to levels slightly above freezing. Crayfish, the decapod crustacean, are most resistant; at an acclimation of 15$sup 0$C, crayfish survive abrupt shock to the point just above freezing. (CH)
Date: January 1, 1975
Creator: Becker, C.D. & Schneider, M.J.
Partner: UNT Libraries Government Documents Department

Spent Fuel Test-Climax: technical measurements data management system description and data presentation

Description: The Spent Fuel Test-Climax (SFT-C) was located 420 m below surface in the Climax Stock granite on the Nevada Test Site. The test was conducted under the technical direction of the Lawrence Livermore National Laboratory (LLNL) as part of the Nevada Nuclear Waste Storage Investigations (NNWSI) for the US Department of Energy. Eleven canisters of spent nuclear reactor fuel were emplaced, along with six electrical simulators, in April-May 1980. The spent fuel canisters were retrieved and the electrical simulators de-energized in March-April 1983. During the test, just over 1000 MW-hr of thermal energy was deposited in the site, causing temperature changes 100{sup 0}C near the canisters, and about 5{sup 0} in the tunnels. More than 900 channels of geotechnical, seismological, and test status data were recorded on nearly continuous basis for about 3-1/2 years, ending in September 1983. Most geotechnical instrumentation was known to be temperature sensitive, and thus would require temperature compensation before interpretation. Accordingly, a 10-in. reel of digital tape was off-loaded and shipped to Livermore every 4 to 8 weeks, where the data were verified, organized into 45 one-million-word files, and temperature corrected. The purpose of this report is to document the receipt and processing of the data by LLNL Livermore personnel, present facts about the history of the instruments which may be important to the interpretation of the data, present the data themselves in graphical form for each instrument over its operating lifetime, document the forms and locations in which the data will be archived, and offer the data to the geotechnical community for future use in understanding and predicting the effects of the storage of heat-generating waste in hard rocks such as granite.
Date: August 1, 1985
Creator: Carlson, R.C.
Partner: UNT Libraries Government Documents Department

Thermal calculations pertaining to experiments in the Yucca Mountain Exploratory Shaft

Description: A series of thermal calculations have been presented that appear to satisfy the needs for design of the Yucca Mountain Exploratory Shaft Tests. The accuracy of the modeling and calculational techniques employed probably exceeds the accuracy of the thermal properties used. The rather close agreement between simple analytical methods (the PLUS Family) and much more complex methods (TRUMP) suggest that the PLUS Family might be appropriate during final design to model, in a single calculation, the entire test array and sequence. Before doing further calculations it is recommended that all available thermal property information be critically evaluated to determine "best" values to be used for conductivity and saturation. Another possibility is to design one or more of the test sequences to approximately duplicate the early phase of Heater Test 1. In that experiment an unplanned power outage for about two days that occurred a week into the experiment gave extremely useful data from which to determine the conductivity and diffusivity. In any case we urge that adequate, properly calibrated instrumentation with data output available on a quasi-real time basis be installed. This would allow us to take advantage of significant power changes (planned or not) and also help "steer" the tests to desired temperatures. Finally, it should be kept in mind that the calculations presented here are strictly thermal. No hydrothermal effects due to liquid and vapor pressures have been considered.
Date: March 1, 1986
Creator: Montan, D.N.
Partner: UNT Libraries Government Documents Department

Physical and chemical changes to rock near electrically heated boreholes at Spent Fuel Test-Climax

Description: Sections of Climax Stock quartz monzonite taken from the vicinity of two electrically heated boreholes at Spent Fuel Test-Climax (SFT-C) have been studied by scanning electron microscopy and optical microscopy for signs of changes in crack structure and in mineralogy resulting from operations at SFT-C. The crack structure, as measured by density of cracks and average crack lengths was found not to have changed as a result of heating, regardless of distance from the heater hole. However, rock near the heater borehole sampled in the north heater drift was found to be more cracked than rock near the borehole sampled in the south heater drift. Mineralogically, the post-test samples are identical to the pre-test samples. No new phases have been formed as a result of the test. 10 refs., 6 figs., 8 tabs.
Date: January 1, 1985
Creator: Beiriger, J.M.; Durham, W.B. & Ryerson, F.J.
Partner: UNT Libraries Government Documents Department

Coupled processes in single fractures, double fractures and fractured porous media

Description: The emplacement of a nuclear waste repository in a fractured porous medium provides a heat source of large dimensions over an extended period of time. It also creates a large cavity in the rock mass, changing significantly the stress field. Such major changes induce various coupled thermohydraulic, hydromechanic and hydrochemical transport processes in the environment around a nuclear waste repository. The present paper gives, first, a general overview of the coupled processes involving thermal, mechanical, hydrological and chemical effects. Then investigations of a number of specific coupled processes are described in the context of fluid flow and transport in a single fracture, two intersecting fractures and a fractured porous medium near a nuclear waste repository. The results are presented and discussed.
Date: December 1, 1986
Creator: Tsang, C.F.
Partner: UNT Libraries Government Documents Department

Reference waste package environment report

Description: One of three candidate repository sites for high-level radioactive waste packages is located at Yucca Mountain, Nevada, in rhyolitic tuff 700 to 1400 ft above the static water table. Calculations indicate that the package environment will experience a maximum temperature of {similar_to}230{sup 0}C at 9 years after emplacement. For the next 300 years the rock within 1 m of the waste packages will remain dehydrated. Preliminary results suggest that the waste package radiation field will have very little effect on the mechanical properties of the rock. Radiolysis products will have a negligible effect on the rock even after rehydration. Unfractured specimens of repository rock show no change in hydrologic characteristics during repeated dehydration-rehydration cycles. Fractured samples with initially high permeabilities show a striking permeability decrease during dehydration-rehydration cycling, which may be due to fracture healing via deposition of silica. Rock-water interaction studies demonstrate low and benign levels of anions and most cations. The development of sorptive secondary phases such as zeolites and clays suggests that anticipated rock-water interaction may produce beneficial changes in the package environment.
Date: October 1, 1986
Creator: Glassley, W.E.
Partner: UNT Libraries Government Documents Department

Estimates of in situ deformability with an NX borehole jack, Spent Fuel Test - Climax, Nevada test site

Description: A series of borehole modulus measurements was obtained at the Spent Fuel Test - Climax (SFT-C) facility following removal of heat sources and a subsequent 1-year cooling period. A total of 212 measurements were obtained using a standard hardrock NX borehole (Goodman) jack. The results of 64 measurements made at the site before heating were reanalyzed for comparison with the post-heat data. Modulus values were calculated from the straight-line portion of the pressure vs displacement curves. Although the deformation modulus was observed to be highly variable, models were developed to explain much of this variability. Typically, spacial effects, anisotropy, and heating effects were present. The test results indicate that the deformation modulus tended to increase in the pillars between the underground openings where temperatures increased about 10{sup 0}C above the ambient 24{sup 0}C during the SFT-C. Conversely, a decrease in modulus was observed where temperatures were near 60{sup 0}C for a three-year period. In most cases, we found the modulus values to be slightly higher for vertical than for horizontal loading. There was a tendency for the modulus to be lower near excavated openings. While this effect was not ubiquitous, it was statistically significant.
Date: December 1, 1985
Creator: Patrick, W.C.; Yow, J.L. Jr. & Axelrod, M.C.
Partner: UNT Libraries Government Documents Department

Some preliminary views of plasma interaction: electromagnetic-launch systems

Description: This discussion outlines a few areas of fundamental research which appear vital for progress in developing advanced propulsion concepts using dc railgun thrusters. We have placed emphasis on the following: (1) dense plasma and high current density influences on changes in microstructure and properties of conventional rail conductors such as Cu, Al, and W alloys or composites; (2) the influences described in (1) on more advanced high temperature, microstrain resistant, materials such as amorphous tungsten; (3) location, description and temporal evolution of current, magnetic field, and losses during intense plasma-current field interactions with conductors; and (4) composite materials and sequentially sectioned structures for more efficient EM dc launcher configuration.
Date: July 14, 1982
Creator: Buckingham, A.C. & Hawke, R.S.
Partner: UNT Libraries Government Documents Department

Shelf life aging of DC-302 silicone molding compound

Description: DC-302 silicone molding compound (Dow Corning Corporation) was packaged 10 different ways, stored at three different temperatures, and tested for spiral flow periodically for 8 months. The material was very stable at 5/sup 0/C and fairly stable at 24/sup 0/C. It was sensitive to heat, however, and was unstable at 55/sup 0/C. Samples that were stored for 12 months at 5/sup 0/C showed no significant change in physical properties.
Date: August 1, 1978
Creator: McFarland, J. W.
Partner: UNT Libraries Government Documents Department

Analysis of thermally induced permeability enhancement in geothermal injection wells

Description: Reinjection of spent geothermal brine is a common means of disposing of geothermal effluents and maintaining reservoir pressures. Contrary to the predictions of two-fluid models (two-viscosity) of nonisothermal injection, an increase of injectivity, with continued injection, is often observed. Injectivity enhancement and thermally-affected pressure transients are particularly apparent in short-term injection tests at the Los Azufres Geothermal Field, Mexico. During an injection test, it is not uncommon to observe that after an initial pressure increase, the pressure decreases with time. As this typically occurs far below the pressure at which hydraulic fracturing is expected, some other mechanism for increasing the near-bore permeability must explain the observed behavior. This paper focuses on calculating the magnitude of the nearbore permeability changes observed in several nonisothermal injection tests conducted at the Los Azufres Geothermal Field.
Date: February 1, 1987
Creator: Benson, S.M.; Daggett, J.S.; Iglesias, E.; Arellano, V. & Ortiz-Ramirez, J.
Partner: UNT Libraries Government Documents Department

A perspective on MoSi{sub 2} based composites

Description: MoSi{sub 2} based composites represent an important new class of ``high temperature structural silicides,`` with significant potential for elevated temperature structural applications in the range of 1200--1600{degrees}C in oxidizing and aggressive environments. The properties of MoSi{sub 2} which make it an attractive matrix for high temperature composites are described and the development history of these materials traced. Latest results on elevated temperature creep resistance, low temperature fracture toughness, and composite oxidation behavior are summarized. Important avenues for future MoSi{sub 2} based composite development are suggested.
Date: June 1, 1992
Creator: Petrovic, J. J. & Vasudevan, A. K.
Partner: UNT Libraries Government Documents Department

[Energy Related Studies Utilizing Microline Thermochronology]. Progress Report, 1990--1991

Description: In our first year of the current funding cycle, we have investigated three interrelated aspects of K-feldspar thermochronology; (1) the Ar diffusion properties and microstructures of K-feldspars, (2) the thermal evolution of the Valles Caldera and (3) the continued development of microanalysis. Results of TEM and light microscopy on heated and unheated samples of MH-10 K-feldspar reveal three classes of substructure are present: (1) cross hatched extinction is common and there is almost no albite/pericline twinning, only tweed microstructure; (2) 5--10 vol. % of this K-feldspar are turbid zones with complex twin and tweed structures at the sub-micron scale and numerous dislocation and strain features; (3) about 20% of the K-feldspar is comprised of 0.01 {times} 0.2-1{mu}m albite exsolution lamellae. The network of fractured/turbid zones divides the sample into blocks of approximately 50 {mu}m and the separation between albite exsolution lamellae produce K-feldspar domains of the order 0.1 {mu}m. Independent crushing and diffusion experiments suggest the scale of the largest domain is order ten`s of micron whereas the smallest domain size is inferred to be {approximately}0.1 {mu}m. Many, and perhaps most, alkali feldspars contain diffusion domains with activation energies that may vary by as much as 8 kcal/mol. An extraordinary consequence of even relatively small variations in activation energy between domains is that the shape of an age spectrum can change dramatically by varying the laboratory heating schedule. We have performed {sup 40}Ar/{sup 39}Ar age spectrum experiments on K-feldspar separated from Proterozoic quartz monzonite taken from a depth of 1.76 km down the VC-2B drill hole, Valles Caldera, north-central New Mexcio.
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department