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A Simplified Instrument for Recording and Indicating Frequency and Intensity of Icing Conditions Encountered in Flight

Description: Memorandum presenting an instrument for recording and indicating the frequency and intensity of aircraft icing conditions to obtain statistical icing data over worldwide air routes during routine airline operations. Data of this type is needed to provide pertinent meteorological information necessary for the optimum design of ice-protection systems. The features that make this particular instrument desirable include the simplicity of operation, freedom from maintenance and operating problems, automatic operation upon encountering an icing condition, visual indications of icing intensity available to the pilot, total weight of 18 pounds, and continuous recorded data.
Date: July 3, 1951
Creator: Perkins, Porter J.; McCullough, Stuart & Lewis, Ralph D.
Partner: UNT Libraries Government Documents Department

A Mechanical Device for Illustrating Airplane Stability

Description: An instrument is described which will illustrate completely in a qualitative sense the longitudinal stability characteristics of an airplane. The instrument is primarily of use for the lecture room, but it is hoped that ultimately it will be possible to obtain quantitative results from it.
Date: December 1921
Creator: Norton, F. E.
Partner: UNT Libraries Government Documents Department

The Development of Electrical Strain Gages

Description: "The design, construction, and properties of an electrical-resistance strain gage consisting of fine wires molded in a laminated plastic are described. The properties of such gages are discussed and also the problems of molding of wires in plastic materials, temperature compensation, and cementing and removal of the gages. Further work to be carried out on the strain gage, together with instrument problems, is discussed" (p. 1).
Date: January 1940
Creator: de Forest, A. V. & Leaderman, H.
Partner: UNT Libraries Government Documents Department

Instrumentation Observations from the U-Frame Lock of the Arkansas River Lock and Dam 5

Description: Report regarding analysis of a lock and dam in the Arkansas River. "The purpose of this study is to take 8 years of instrumentation data from Lock No. 5 and report it in such a manner that it can be used later in other studies, such as a finite element analysis. Included is a discussion of the quality of the data and a brief comparison of measured values with design cases for several soil-structure interaction cases" (p. 5).
Date: August 1978
Creator: Leach, Roy E.
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Investigation of a Number of Total-Pressure Tubes at High Angles of Attack -- Subsonic, Transonic, and Supersonic Speeds

Description: "The effect of inclination of the airstream on the measured pressures of 54 total-pressure tubes has been determined for angles of attack up to 60 degrees and over a Mach number range from 0.26 to 1.62. The investigation was conducted in five wind tunnels at the Langley Aeronautical Laboratory" (p. 495).
Date: January 17, 1956
Creator: Gracey, William
Partner: UNT Libraries Government Documents Department

Corrugated Metal Diaphragms for Aircraft Pressure-Measuring Instruments

Description: Note presenting a description of a large number of corrugated diaphragms of beryllium copper, phosphor bronze, and Z-nickel with geometrically similar outlines but various diameters and thicknesses were formed by hydraulic pressing. The apparatus and technique used in the manufacture, testing, and heat treatment are described. Results regarding pressure-deflection curves, load limit, effect of center reinforcing, snap-action diaphragms, deflection traverse, thickness variations, and concentrated central loads are provided.
Date: November 1939
Creator: Wildhack, W. A. & Goerke, V. H.
Partner: UNT Libraries Government Documents Department

Static-pressure error calibrations for nose-boom airspeed installations of 17 airplanes

Description: Report presenting a flight investigation to determine the static-pressure errors for nose-boom airspeed installations of 17 airplanes. Both research-type and service-type aircraft are covered in the investigation. Results indicated that the magnitude of static-pressure errors for the airspeed installations of all the airplanes is shown to vary with airplane geometric characteristics that include nose-boom length, fuselage diameter, and nose fineness ratio.
Date: March 13, 1957
Creator: Larson, Terry J.; Stillwell, Wendell H. & Armistead, Katharine H.
Partner: UNT Libraries Government Documents Department

Acoustic Leak Detection for District Heating Systems

Description: An acoustic leak detection facility was completed and used to evaluate the capability of piezoelectric sensors, accelerometers, and capacitance microphones to detect and locate gas and water leaks in underground district heating and cooling (DHC) piping. Leak detection sensitivity and location capabilities for DHC systems were estimated from laboratory data and from data obtained from the underground DH system in Scranton, Pennsylvania, where acoustic background noise levels and acoustic signals from field-induced steam leaks were acquired. Acoustic detection of leaks with flow rates of less than 10 gpm is possible at a distance of several hundred meters, with a location accuracy of a few meters. Although steam leaks of comparable mass loss can be detected over a similar range with transducers mounted on the pipe outer wall, location accuracy of a few meters over this range may only be possible with transducers in direct contract with the steam. Intrusive sensors may also be necessary to detect and locate leaks in plastic pipe.
Date: February 1988
Creator: Kupperman, D. S. & Karvelas, D. E.
Partner: UNT Libraries Government Documents Department

Test and Evaluation of the Argonne BPAC10 Series Air Chamber Calorimeter Designed for 20 Minute Measurements

Description: This paper is the final report on DOE-OSS Task ANLE88002 Fast Air Chamber Calorimetry.'' The task objective was to design, construct, and test an isothermal air chamber calorimeter for plutonium assay of bulk samples that would meet the following requirements for sample power measurement: average sample measurement time less than 20 minutes. Measurement of samples with power output up to 10 W. Precision of better than 1% RSD for sample power greater than 1 W. Precision better than 0.010 watt SD, for sample power less than 1 W. This report gives a description of the calorimeter hardware and software and discusses the test results. The instrument operating procedure, included as an appendix, gives examples of typical input/output and explains the menu driven software.
Date: October 1990
Creator: Perry, Ronald B.; Fiarman, Sidney; Jung, Erwin A. & Cremers, Teresa
Partner: UNT Libraries Government Documents Department

Rapid mass spectrometric DNA diagnostics for assessing microbial community activity during bioremediation. 1998 annual progress report

Description: 'Biological activity has often been attributed to changes in pollutant profiles found in contaminated soils when abiotic processes actually caused pollutant removal. Careful evaluation of bioremediation necessitates that all transformation and removal pathways are anticipated so that the pathways are controlled or monitored. The author''s work is directed at evaluating a monitoring strategy that relies on the combined use of DNA diagnostic procedures and mass spectrometry as the detection scheme. The intent is to track bioremediation by measuring the occurrence of genes in soil samples that are known to code for enzymes capable of degrading specific pollutants. Matrix-assisted-laser-desorption- ionization time-of-flight mass spectrometry (MALDI-TOF-MS) offers the possibility for automation and high throughput PNA detection as is needed to track the course of bioremediation over large polluted areas.'
Date: June 1, 1998
Creator: Benner, W.H.
Partner: UNT Libraries Government Documents Department

Rapid mass spectrometric DNA diagnostics for assessing microbial community activity during bioremediation. 1997 annual progress report

Description: 'The effort of the past year''s activities, which covers the first year of the project, was directed at developing DNA-based diagnostic procedures for implementation in high through-put analytical instrumentation. The diagnostic procedures under evaluation are designed to identify specific genes in soil microorganisms that code for pollutant-degrading enzymes. Current DNA-based diagnostic procedures, such as the ligase chain reaction (LCR) and the polymerase chain reaction (PCR), rely on gel electrophoresis as a way to score a diagnostic test. The authors are attempting to implement time-of-flight (TOF) mass spectrometry as a replacement for gel separations because of its speed advantage and potential for sample automation. The authors anticipate that if TOF techniques can be implemented in the procedures, then a very large number of microorganisms and soil samples can be screened for the presence of specific pollutant-degrading genes. The use of DNA-based procedures for the detection of biodegrading organisms or genes that code for pollutant-degrading enzymes constitutes a critical technology for following biochemical transformation and substantiating the impact of bioremediation. DNA-based technology has been demonstrated to be a sensitive technique for tracking micro-organism activity at the molecular level. These procedures can be tuned to identify groups of organisms, specific organisms, and activity at the molecular level. They are developing a P-monitoring strategy that relies on the combined use of DNA diagnostics with mass spectrometry as the detection scheme. The intent of this work is a two-fold evaluation of (1) the feasibility of replacing the use of gel separations for identifying polymerase chain reaction (PCR) products with a rapid and automatable form of electrospray mass spectrometry and (2) the use of matrix-assisted-laser-desorption-ionization mass spectrometry (MALDI-MS) as a tool to score oligonucleotide ligation assays (OLA).'
Date: January 1, 1997
Creator: Benner, W.H. & Hunter-Cevera, J.
Partner: UNT Libraries Government Documents Department

Reduction of sample volume and waste generation in acid/base titrations using microelectrodes

Description: The Analytical Development Section (ADS) has developed microelectrode methods for use with pH titrations and pH determinations. These microelectrode methods offer increased sensitivity and enable analyses to be done with smaller sample and buffer volumes than are used with standard size electrodes. This report establishes the technical validity of the methods and describes the application of these methods to decreased detection limits, decreased waste generation, and decreased radiation exposure.
Date: March 22, 1996
Creator: Ekechukwu, A.A.
Partner: UNT Libraries Government Documents Department

Mobile Measurement of an Atmospheric Tracer

Description: This paper describes a mobile analyzer for sulfur hexafluoride, an atmospheric tracer. A commercial instrument is used on-board a moving vehicle to measure tracer concentrations in the parts per trillion (ppt) range. This instrument provides rapid, in-the-field data at minimum cost.
Date: March 9, 2001
Creator: Milham, R.C.
Partner: UNT Libraries Government Documents Department