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Evaluation of unencapsulated ceramic monolithic and MOS thin-film capacitors (25 to 300/sup 0/C)

Description: Several commercial monolithic ceramic and thin-film MOS chip capacitors were evaluated for use in high temperature (300/sup 0/C) geothermal instrumentation. Characteristics of the commonly used dielectric materials (NPO, X7R, BX) and temperature dependence of the insulation resistance are briefly discussed. Some ceramic capacitors with NPO dielectric materials had insulation resistances above 10 megohms at 300/sup 0/C and less than 2% change in capacitance from 25/sup 0/C to 300/sup 0/C, while … more
Date: January 1, 1982
Creator: Nance, W.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A capacitance-based proximity sensor for whole arm obstacle avoidance

Description: This paper addresses the issue of collision avoidance in unknown or partially modeled environments using a capacitive sensor. An eight channel capacitance-based sensor system which can detect obstacles up to 400 mm (16 inches) away has been developed. This sensor can detect both conductive and non-conductive obstacles of arbitrary color and shape. The sensor hardware is reliable and inexpensive, and it may be fabricated using flexible printed circuit boards to provide whole-arm and joint protec… more
Date: January 1, 1991
Creator: Novak, J.L. & Feddema, J.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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T Tank Farm Interim Surface Barrier Demonstration -- Vadose Zone Monitoring FY07 Report

Description: CH2M HILL Hanford Group, Inc. is currently in the process of constructing a temporary surface barrier over a portion of the T Tank Farm as part of the T farm Interim Surface Barrier Demonstration Project. The surface barrier is designed to prevent the infiltration of precipitation into the contaminated soil zone created by the Tank T-106 leak and minimize movement of the contamination. As part of the demonstration effort, vadose zone moisture monitoring is being performed to assess the effectiv… more
Date: January 11, 2008
Creator: Zhang, Z. F.; Strickland, Christopher E.; Keller, Jason M.; Wittreich, Curtis D. & Sydnor, Harold A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Testing of double-layer capacitors for high reliability applications

Description: Double-Layer Capacitors (DLCs) have been used mainly for computer memory backup in consumer applications during the last ten years. Their high capacitance density, along with maintenance-free operation, makes them suited for these applications. In recent years users, mostly in military applications, have expressed interest in using DLCs in high reliability applications both for backup power and pulse power applications. To meet this need, developers have pursued technologies that use carbon and… more
Date: January 1, 1991
Creator: Clark, N.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of equivalent capacitances between mutually coupled windings

Description: The interwinding capacitance between mutually coupled windings may play a significant role in the transient analysis of these windings. Neglecting this capacitance or dividing it equally among the interwinding node pairs would then result in considerable inaccuracy in the analysis. A method is proposed to calculate equivalent interwinding capacitances which will reduce this inaccuracy. It is illustrated by simple winding models.
Date: January 1, 1986
Creator: Chowdhuri, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simulations of surface capacitance effects on potentiostat response following disruption of passivity

Description: Following depassivation of potentiostatically controlled metals, complex current transients arise because of the current distribution and the capacitance of the surrounding passive metal/solution interface. A computer simulation of the cross-section has been developed. Examples following an instantaneous scratch are given for changes in the placement of the reference electrode and changes in the area of the passive surface.
Date: January 1, 1991
Creator: Isaacs, H. S.; Davenport, A. J. (Brookhaven National Lab., Upton, NY (United States)) & Frankel, G. S. (IBM Research Div., Yorktown Heights, NY (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Two-part-liquid-mixture percentage measurement using a flow-through capacitance sensor

Description: A flow-through capacitance sensor with application-specific electronics that includes auto-calibration and fail-safe circuitry has been built and tested to measure the percentage of tributyl phosphate (TBP) in n-dodecane. The system has been tested with the flow-through sensor at 100 foot distance from the electronics and shows no sensitivity to cable movement. The calibration data fits a second degree polynomial well. 6 figs., 1 tab.
Date: January 1, 1991
Creator: Piper, T.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evidence for bifurcation and universal chaotic behavior in nonlinear semiconducting devices

Description: Bifurcations, chaos, and extensive periodic windows in the chaotic regime are observed for a driven LRC circuit, the capacitive element being a nonlinear varactor diode. Measurements include power spectral analysis; real time amplitude data; phase portraits; and a bifurcation diagram, obtained by sampling methods. The effects of added external noise are studied. These data yield experimental determinations of several of the universal numbers predicted to characterize nonlinear systems having th… more
Date: January 1, 1982
Creator: Testa, J.; Perez, J. & Jeffries, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optimal design of high speed analog APD receivers

Description: In order to provide optical to electrical conversion of high speed analog signals, avalanche photodiode receivers must be optimized for several parameters. Among these parameters are receiver amplifier noise, APD noise, and bandwidth. Optimization of these parameters requires a theoretical understanding of each of the parameters and their interactions. In the first part of this paper the theoretical design of an avalanche photodiode optical receiver will be discussed with attention to the param… more
Date: January 1, 1988
Creator: Smith, R. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development and utilization of new diagnostics for dense-phase pneumatic transport

Description: Dense-phase pneumatic transport is an attractive means of conveying solids. The main objective of this work is to develop probes for local measurements of solid velocity and holdup in dense gas-solid flows. In particular, we have designed capacitance probes to measure local, time-dependent particle concentrations, and a new optical fiber probe based on laser-induced-phosphorescence to measure particle velocities. A prototype of the optical fiber probe was tested during the previous quarter. In … more
Date: January 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sputtered amorphous silicon solar cells. Quarterly report No. 2, October 22, 1980-January 22, 1981

Description: The mechanism of hydrogen incorporation during the film growth was investigated through hydrogen content studies. The data are consistent with a kinetic model of hydrogen incorporation. The hole mobility-lifetime products were measured on a-SiH/sub x//metal Schottky barrier structures with a new method utilizing optical absorption, collection efficiency, and capacitance voltage measurements. The diode properties of reactively sputtered hydrogenated amorphous silicon Schottky barrier structures … more
Date: January 1, 1981
Creator: Moustakas, T. D.; Morel, D. L. & Wronski, C. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fast Neutron Radiation Damage Effects on High Resistivity Silicon Junction Detectors. Revision

Description: P{sup +}{minus}n{sup {minus}}{minus}n{sup +} silicon radiation detectors made of high resistivity Si material ({rho} {ge} 2 k{Omega}-cm) were irradiated to a neutron fluence of a few times of 10{sup 13} n/cm{sup 2}. Dependence of detector leakage current, reverse bias capacitance, and effective doping concentration of the Si substrate on the neutron fluence have been systematically studied. It has been found that the detector leakage current increases linearly with neutron fluence in the range … more
Date: January 1992
Creator: Li, Zheng & Kraner, H. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Induction Linac Pulsers

Description: The pulsers used in most of the induction linacs evolved from the very large body of work that was done in the U.S. and Great Britain during the development of the pulsed magnetron for radar. The radar modulators started at {approx}100 kW and reached >10 MW by 1945. A typical pulse length was 1 {mu}s at a repetition rate of 1,000 pps. A very comprehensive account of the modulator development is Pulse Generators by Lebacqz and Glasoe, one of the Radiation Laboratory Series. There are many per… more
Date: January 7, 2011
Creator: Faltens, Andris
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Carbide-Derived Carbons with Tunable Porosity Optimized for Hydrogen Storage

Description: On-board hydrogen storage is a key requirement for fuel cell-powered cars and trucks. Porous carbon-based materials can in principle adsorb more hydrogen per unit weight at room temperature than liquid hydrogen at -176 oC. Achieving this goal requires interconnected pores with very high internal surface area, and binding energies between hydrogen and carbon significantly enhanced relative to H2 on graphite. In this project a systematic study of carbide-derived carbons, a novel form of porous ca… more
Date: January 7, 2010
Creator: Fisher, John E.; Gogotsi, Yury & Yildirim, Taner
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Non-contact optical three dimensional liner metrology.

Description: We optically captured the 'as-built' liner geometry of NTLX (near term liner experiments) for Shiva Star using ultra-precision ranging lasers. We subsequently verified the resulting digitized geometry against the 3D CAD model of the part. The results confirmed that the Liner contours are within designed tolerances but revealed subtle fabrication artifacts that would typically go undetected. These features included centimeters long waviness and saddle and bulge regions of 1 micron or less in mag… more
Date: January 1, 2001
Creator: Sebring, R. J. (Robert J.); Anderson, W. E. (Wallace E.); Bartos, J. J. (Jacob J.); Garcia, F. (Fermin); Randolph, B. (Blaine); Salazar, M. A. (Mike A.) et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

T Tank Farm Interim Surface Barrier Demonstration - Vadose Zone Monitoring FY09 Report

Description: DOE’s Office of River Protection constructed a temporary surface barrier over a portion of the T Tank Farm as part of the T Farm Interim Surface Barrier Demonstration Project. As part of the demonstration effort, vadose zone moisture is being monitored to assess the effectiveness of the barrier at reducing soil moisture. A solar-powered system was installed to continuously monitor soil water conditions at four locations (i.e., instrument Nests A, B, C, and D) beneath the barrier and outside the… more
Date: January 1, 2010
Creator: Zhang, Z. F.; Strickland, Christopher E.; Field, Jim G. & Parker, Danny L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Studies of Basic Electronic Properties of CdTe-Based Solar Cells and Their Evolution During Processing and Stress; Annual Technical Report, 1 November 2005 - 31 October 2006

Description: We describe the results of our continuing study of deep electronic states controlling open-circuit voltage in CdTe/CdS thin-film solar cells (Task 1). The study includes: (1) analysis of factors affecting trap signatures derived from admittance spectroscopy and capacitance transients measurements, such as activation-energy capture cross-sections and trap-density estimates, and (2) comparative studies of cells received from four different sources and prepared with significant variations in cell … more
Date: January 1, 2007
Creator: Beach, J.; Seymour, F. H.; Kaydanov, V. I. & Ohno, T. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Fast neutron radiation damage effects on high resistivity silicon junction detectors

Description: P{sup +}{minus}n{sup {minus}}{minus}n{sup +} silicon radiation detectors made of high resistivity Si material ({rho} {ge} 2 k{Omega}-cm) were irradiated to a neutron fluence of a few times of 10{sup 13} n/cm{sup 2}. Dependence of detector leakage current, reverse bias capacitance, and effective doping concentration of the Si substrate on the neutron fluence have been systematically studied. It has been found that the detector leakage current increases linearly with neutron fluence in the range … more
Date: January 1, 1992
Creator: Li, Zheng & Kraner, H. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Four-Plate Pick-Up Capacitance and Sensitivity Calculations

Description: The goal of calculations presented in this note is to find and maximize the sensitivity of a quadrupole pick-up currently being designed. The calculations are made using the CERN package Poisson. The range of electrode widths under consideration is:.006m < w < .03. Studies indicate that sensitivity is maximized in this range by the smallest width plate if the electronics contributes negligible capacitance. The plate size for which the sensitivity is optimized increases with increasing ele… more
Date: January 1, 1991
Creator: O'Day, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Technique for Determining Non-Linear Circuit Parameters from Ring Down Data

Description: We present a technique for determining non-linear resistances, capacitances, and inductances from ring down data in a non-linear RLC circuit. Although the governing differential equations are non-linear, we are able to solve this problem using linear least squares without doing any sort of non-linear iteration.
Date: January 1, 2003
Creator: Romero, Louis; Dickey, Fred M. & Dison, Holly
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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