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A 10 GHz BANDWIDTH, SINGLE TRANSIENT, DIGITIZED OSCILLOSCOPE WITH 20 GHz CAPABILITY (open access)

A 10 GHz BANDWIDTH, SINGLE TRANSIENT, DIGITIZED OSCILLOSCOPE WITH 20 GHz CAPABILITY

EG&G/EM has developed an oscilloscope with a {minus}3 dB bandwidth greater than 10 GHz. Its rolloff characteristics are such that single-transient data greater than 20 GHz may be captured. A demountable CCD camera records the oscilloscope trace and is provided with PC-compatible capture and data processing software. The capabilities of the oscilloscope, camera, and its processing software are described and examples of the system`s performance is shown.
Date: January 24, 1994
Creator: Hudson, C. L.; Kocimski, S. M.; Spector, J.; Thomas, J. B. & Woodstra, R. R.
System: The UNT Digital Library
Absolute Bunch Length Measurements at the ALS by Incoherent Synchrotron Radiation Fluctuation Analysis (open access)

Absolute Bunch Length Measurements at the ALS by Incoherent Synchrotron Radiation Fluctuation Analysis

By analyzing the pulse to pulse intensity fluctuations of the radiation emitted by a charge particle in the incoherent part of the spectrum, it is possible to extract information about the spatial distribution of the beam. At the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory, we have developed and tested a simple scheme based on this principle that allows for the absolute measurement of the bunch length. A description of the method and the experimental results are presented.
Date: January 24, 2008
Creator: Filippetto, D.; /Frascati; Sannibale, F.; Zolotorev, Max Samuil; /LBL, Berkeley; Stupakov, G.V. et al.
System: The UNT Digital Library
Adolescents’ Physical Activity and Depressive Symptoms: A Psychosocial Mechanism (open access)

Adolescents’ Physical Activity and Depressive Symptoms: A Psychosocial Mechanism

Article tests a hypothesized path model of Theory of Planned Behavior (TPB) variables (i.e., attitude toward behavior, subjective norm, perceived behavioral control, and intention) with physical activity (PA) and depressive symptoms. The findings support the theoretical tenets of TPB and provide empirical evidence of the psychosocial mechanism of PA and depressive symptoms in Chinese adolescents. It suggests that building PA intervention strategies while considering the TPB framework may promote adolescents’ physical and mental health.
Date: December 31, 2021
Creator: Shen, Liang; Gu, Xiangli; Zhang, Tao & Lee, Joonyoung
System: The UNT Digital Library
Adsorption characteristics of rocks from vapor-dominated geothermal reservoir at the Geysers, CA (open access)

Adsorption characteristics of rocks from vapor-dominated geothermal reservoir at the Geysers, CA

This paper reports on a continuing experimental effort to characterize the adsorption behavior of rocks from The Geysers steam field in California. We show adsorption results obtained for 36 rock samples. All of the adsorption isotherms plotted on the same graph exhibit an envelope of isotherms. The minimum and the maximum values of the slope (or rate of adsorption) and of the magnitude within this envelope of isotherms belonged to the UOC-1 (felsite) and NCPA B-5 (serpentine) samples. The values of surface area and porosity, and pore size distribution for 19 of the samples indicated a very weak correlation with adsorption. An interpretation of the pore size distributions and the liquid saturation isotherms suggests that the change in the slope and the magnitude of the adsorption isotherms within the envelope is controlled primarily by the physical adsorption mechanism instead of capillary condensation. Grain-size and framework grain to matrix ratio are found to be insufficient to characterize this adsorption behavior. An accurate identification of the mineralogy of the samples will be essential to complete this analysis.
Date: January 24, 1996
Creator: Satik, Cengiz; Walters, Mark & Horne, Roland N.
System: The UNT Digital Library
Advances in the chemical conversion of energetic materials to higher value products (open access)

Advances in the chemical conversion of energetic materials to higher value products

The objective of this program is to develop novel, innovative solutions for the disposal of surplus explosives resulting from the demilitarization of nuclear and conventional munitions by DOE and DoD. Studies related to the conversion of TNT and Explosive D to potentially useful materials are described. The paper describes the feasibility of conversion of TNT to TATB; conversion of TNT to 3,5-diamino-2,4,6-trinitrotoluene (DATNT); conversion of TNT to tolylene 2,4-diisocyanate (TDI) and nitrotolylene and diisocyanate (NTDI); chelating resins derived from trinitroarenes.
Date: January 24, 1995
Creator: Mitchell, A.R.; Pagoria, P.F. & Sanner, R.D.
System: The UNT Digital Library
Altheim geothermal Plant for electricity production by Organic Rankine Cycle turbogenerator (open access)

Altheim geothermal Plant for electricity production by Organic Rankine Cycle turbogenerator

The paper describes the plan of the town Altheim in Upper Austria to produce electricity by an Organic Rankine Cycle-turbogenerator in the field of utilization of low temperatured thermal water. The aim of the project is to improve the technical and economic situation of the geothermal plant.
Date: January 24, 1996
Creator: Pernecker, Gerhard & Ruhland, Johannes
System: The UNT Digital Library
Analysis of pressure interference tests for well S-4 and slim hole KY-1: Sumikawa Geothermal Field, Japan (open access)

Analysis of pressure interference tests for well S-4 and slim hole KY-1: Sumikawa Geothermal Field, Japan

Discharge of Sumikawa well S-4 in the fall of 1986 was accompanied by in situ boiling. In May of 1989, cold water was injected intermittently into well S-4. During both of these tests, a pressure response was observed in KY-1. In this paper, a new interpretation of the latter pressure interference data is presented. While interpretation of the 1989 test is straightforward, in situ boiling during the 1986 test creates substantial difficulties in assigning an “effective discharge rate”. Because of uncertainties in the “effective discharge rate” history for the 1986 test, the distances to the various reservoir boundaries are not well constrained.
Date: January 24, 1996
Creator: Garg, S. K. & Owusu, L. A.
System: The UNT Digital Library
Analysis of the pressure response of high angle multiple (HAM) fractures intersecting a wellbore (open access)

Analysis of the pressure response of high angle multiple (HAM) fractures intersecting a wellbore

Several methods have been presented in the literature for analyzing transient pressure data of fractured wells. We tested with some model studies based on the solutions to the 3D problem of multiple high-angle fractures (HAM) intersecting a wellbore. The model solutions representing transient pressure behavior of HAM fractures are defined in terms of 3D rectilinear coordinates. The HAM fracture model equations include the finite conductivity of the fractures, and our solutions reduce to previously published results for the special case of vertical fractures and/or infinite-conductivity fractures. A computer program, MULFRAC, has been provided to calculate the dimensionless drawdown at the wellbore. This paper shows the solutions of MULFRAC, some comparison of MULFRAC results with published special cases.
Date: January 24, 1996
Creator: Ujo, Satoshi; Osato, Kazumi; Schroeder, Ron C. & Arihara, Norio
System: The UNT Digital Library
Application of Morse Theory to Analysis of Rayleigh-Taylor Topology (open access)

Application of Morse Theory to Analysis of Rayleigh-Taylor Topology

We present a novel Morse Theory approach for the analysis of the complex topology of the Rayleigh-Taylor mixing layer. We automatically extract bubble structures at multiple scales and identify the resolution of interest. Quantitative analysis of bubble counts over time highlights distinct mixing trends for a high-resolution Direct Numerical Simulation (DNS) [1].
Date: January 24, 2007
Creator: Miller, P L; Bremer, P T; Cabot, W H; Cook, A W; Laney, D E; Mascarenhas, A A et al.
System: The UNT Digital Library
The aqueous chemistry of aluminum: A new approach to high temperature solubility measurements (open access)

The aqueous chemistry of aluminum: A new approach to high temperature solubility measurements

The solubility of boehmite, AlO(OH), has been measured as a function of pH (2 - 10, depending on ionic strength), temperature (100 - 250&deg;C) and ionic strength (0.03 - 1 molal, NaCl) in a hydrogen-electrode concentration cell, HECC, which provided in situ measurement of hydrogen ion molality. Samples of the solution were withdrawn after the pH reading stabilized for analysis of total aluminum content by ion chromatography. Acidic or basic titrant could then be metered into the cell to affect a change in the pH of the solution. The direction of approach to the equilibrium saturated state could be readily varied to ensure that the system was reversible thermodynamically. This represents our second application of direct pH measurement to high temperature solubility studies. The results at low ionic strength are compared with those from two recently-reported high-temperature studies of boehmite solubility, which relied on the conventional batch technique. Comparisons are also made with the low temperature (<90&deg;C) hydrolysis constants for aluminum garnered from solubility measurements with gibbsite as the stable phase. Based on these preliminary results, it is possible to draw some general conclusions concerning the relative importance of the aluminum species in solution and to reduce significantly the number …
Date: January 24, 1996
Creator: Palmer, Donald A.; Wesolowski, David J. & Benezeth, Pascale
System: The UNT Digital Library
Assessment of the renewable groundwater resources of Wadi El-Arish, Sinai, Egypt, by using remote sensing, digital terrain elevation, and meteorological data (open access)

Assessment of the renewable groundwater resources of Wadi El-Arish, Sinai, Egypt, by using remote sensing, digital terrain elevation, and meteorological data

The authors show that the most popular method to simulate Bose-Einstein (BE) interference effects predicts negligible correlations between identical pions originating from the hadronic decay of different W's produced in e{sup +}e{sup {minus}} {yields} W{sup +}W{sup {minus}} {yields} 4 jets at typical linear collider energies.
Date: January 24, 2000
Creator: Gheith, H. M. & Sultan, M. I.
System: The UNT Digital Library
Beam-target interaction in heavy ion fusion (open access)

Beam-target interaction in heavy ion fusion

The beam-target interaction in heavy ion fusion is theoretically understood, but experimental verification at appropriate beam intensities is not possible using existing accelerators. If fusion-intensity ion beams were to lose significantly less energy in passing through matter than calculated it would increase the cost of heavy ion fusion. In the worst case the cost scaling is such that a 25% decrease in energy loss would increase the cost of the accelerator by roughly 10%. In this paper we show that fundamental considerations place a lower bound on ion energy loss. The lower bound is not significantly less than the expected energy loss obtained from detailed calculations.
Date: January 24, 1979
Creator: Bangerter, R.O.
System: The UNT Digital Library
Brief report from the Tevatron (open access)

Brief report from the Tevatron

The authors report on the B physics prospects from the Fermilab Tevatron, summarizing the B physics goals of the CDF and D0 experiments using their upgraded detectors. They discuss the time schedule for completion of the detector upgrades and summarize the current measurement of the CP violation parameter sin 2{beta} at CDF.
Date: January 24, 2000
Creator: Paulini, M.
System: The UNT Digital Library
Bubble Counts for Rayleigh-Taylor Instability Using Image Analysis (open access)

Bubble Counts for Rayleigh-Taylor Instability Using Image Analysis

We describe the use of image analysis to count bubbles in 3-D, large-scale, LES [1] and DNS [2] of the Rayleigh-Taylor instability. We analyze these massive datasets by first converting the 3-D data to 2-D, then counting the bubbles in the 2-D data. Our plots for the bubble count indicate there are four distinct regimes in the process of the mixing of the two fluids. We also show that our results are relatively insensitive to the choice of parameters in our analysis algorithms.
Date: January 24, 2007
Creator: Miller, P L; Gezahegne, A G; Cook, A W; Cabot, W H & Kamath, C
System: The UNT Digital Library
CHARACTERIZATION OF GLOVEBOX GLOVES FOR THE SAVANNAH RIVER SITE (open access)

CHARACTERIZATION OF GLOVEBOX GLOVES FOR THE SAVANNAH RIVER SITE

A task was undertaken to characterize glovebox gloves that are currently used in the facilities at Savannah River Site (SRS) as well as some experimental and advanced compound gloves that have been proposed for use. Gloves from four manufacturers were tested for permeation in hydrogen and air, thermal stability, tensile properties, puncture resistance and dynamic mechanical response. The gloves were compared to each other within the type and also to the butyl rubber glove that is widely used at the SRS. The permeation testing demonstrated that the butyl compounds from three of the vendors behaved similarly and exhibited hydrogen permeabilities of .52&amp;#8208;.84 x10{sup &amp;#8208;7} cc H{sub 2}*cm / (cm{sup 2}*atm). The Viton� glove performed at the lower edge of this bound, while the more advanced composite gloves exhibited permeabilities greater than a factor of two compared to butyl. Thermogravimetric analysis was used to determine the amount of material lost under slightly aggressive conditions. Glove losses are important since they can affect the life of glovebox stripper systems. During testing at 90, 120, and 150�C, the samples lost most of the mass in the initial 60 minutes of thermal exposure and as expected increasing the temperature increased the mass loss and …
Date: January 24, 2013
Creator: Korinko, P.
System: The UNT Digital Library
Characterization of high-power lithium-ion cells during constant current cycling. Part I. Cycle performance and electrochemical diagnostics (open access)

Characterization of high-power lithium-ion cells during constant current cycling. Part I. Cycle performance and electrochemical diagnostics

Twelve-cm{sup 2} pouch type lithium-ion cells were assembled with graphite anodes, LiNi{sub 0.8}Co{sub 0.15}Al{sub 0.05}O{sub 2} cathodes and 1M LiPF{sub 6}/EC/DEC electrolyte. These pouch cells were cycled at different depths of discharge (100 percent and 70 percent DOD) at room temperature to investigate cycle performance and pulse power capability. The capacity loss and power fade of the cells cycled over 100 percent DOD was significantly faster than the cell cycled over 70 percent DOD. The overall cell impedance increased with cycling, although the ohmic resistance from the electrolyte was almost constant. From electrochemical analysis of each electrode after cycling, structural and/or impedance changes in the cathode are responsible for most of the capacity and power fade, not the consumption of cycleable Li from side-reactions.
Date: January 24, 2003
Creator: Shim, Joongpyo & Striebel, Kathryn A.
System: The UNT Digital Library
Chemical hydrofracturing of the Hot Dry Rock reservoir (open access)

Chemical hydrofracturing of the Hot Dry Rock reservoir

The experimental study of the water-rock interaction shows that the secondary mineral assemblage depends on the water composition. For example, granite-pure water interaction produces zeolites (relatively low-dense, Mg-poor minerals), whereas seawater yields chlorites (high-dense, Mg-rich minerals). The reactions have volumetric effects from several % to 20 % in magnitude. Volume deformations in the heterogeneous matrix cause uneven mechanical strains. Reactions with the effect of about 0,1 vol.% may cause strains of the order of 100-1000 bars being enough for destruction of rocks. Signs and magnitudes of local volume changes depend on the mineral composition of the secondary assemblage. Hence, one can provide either healing or cracking of primary fractures, as desired, by changing the composition of water in the water-felsic rock system where some elements (Mg, Fe) are in lack. The techniques of "chemical hydrofracturing" looks promising as applied to a granite HDR massif. One can regulate the permeability of fractured flow paths by changing in concord the composition and pressure of the injected water. This approach should promote efficient extraction of the petrothermal energy.
Date: January 24, 1996
Creator: Yakovlev, Leonid
System: The UNT Digital Library
Classification of Geothermal Resources - An engineering approach (open access)

Classification of Geothermal Resources - An engineering approach

Geothermal resources have been classified into low, intermediate and high enthalpy resources by their reservoir temperatures. The temperature ranges used are arbitrary and there is not a general agreement. Geothermal resources should be classified by two independent thermodynamic properties of their fluids at the wellhead. They should reflect the fluids availability to do work. By setting the triple point of water as the sink condition, and normalising the fluids specific exergies by the maximum specific exergy of dry saturated steam, geothermal resources can be classified into high, medium, and low category resources by their specific exergy indices (SEI) of greater than 0.5, between 0.05 and 0.5, and less than 0.05. These correspond to geothermal fluids having exergies greater than that of dry saturated steam at 1 bar absolute, between saturated water and dry saturated steam at 1 bar absolute, and less than saturated water at 1 bar absolute respectively.
Date: January 24, 1996
Creator: Lee, K. C.
System: The UNT Digital Library
Comments on "Solubility and Dissolution Thermodynamic Data of Cefpiramide in Pure Solvents and Binary Solvents" (open access)

Comments on "Solubility and Dissolution Thermodynamic Data of Cefpiramide in Pure Solvents and Binary Solvents"

Abstract: Errors are found in the mathematical correlation based on the combined Jouyban-Acree and Modified Apelblat model for describing the variation in the mole fraction solubility of cefpiramide with temperature and solvent composition for the binary aqueous-ethanol solvent system. The equation coefficents given by Tang and coworkers, when substituted into the model equation, do not yield the authors' calculated mole fraction solubilities of cefpiramide.
Date: January 24, 2018
Creator: Acree, William E. (William Eugene)
System: The UNT Digital Library
A Comparison of Ultrasound Tomography Methods in Circular Geometry (open access)

A Comparison of Ultrasound Tomography Methods in Circular Geometry

Extremely high quality data was acquired using an experimental ultrasound scanner developed at Lawrence Livermore National Laboratory using a 2D ring geometry with up to 720 transmitter/receiver transducer positions. This unique geometry allows reflection and transmission modes and transmission imaging and quantification of a 3D volume using 2D slice data. Standard image reconstruction methods were applied to the data including straight-ray filtered back projection, reflection tomography, and diffraction tomography. Newer approaches were also tested such as full wave, full wave adjoint method, bent-ray filtered back projection, and full-aperture tomography. A variety of data sets were collected including a formalin-fixed human breast tissue sample, a commercial ultrasound complex breast phantom, and cylindrical objects with and without inclusions. The resulting reconstruction quality of the images ranges from poor to excellent. The method and results of this study are described including like-data reconstructions produced by different algorithms with side-by-side image comparisons. Comparisons to medical B-scan and x-ray CT scan images are also shown. Reconstruction methods with respect to image quality using resolution, noise, and quantitative accuracy, and computational efficiency metrics will also be discussed.
Date: January 24, 2002
Creator: Leach, R. R.; Azevedo, S. G.; Berryman, J. G.; Bertete-Aquirre, H. R.; Chambers, D. H.; Mast, J. E. et al.
System: The UNT Digital Library
Complexation of U(VI) with 1-Hydroxyethane-1,1-diphosphonicAcid (HEDPA) in Acidic to Basic Solutions (open access)

Complexation of U(VI) with 1-Hydroxyethane-1,1-diphosphonicAcid (HEDPA) in Acidic to Basic Solutions

Complexation of U(VI) with 1-hydroxyethane-1,1-diphosphonic acid (HEDPA) in acidic to basic solutions has been studied with multiple techniques. A number of 1:1 (UO{sub 2}H{sub 3}L), 1:2 (UO{sub 2}H{sub j}L{sub 2} where j = 4, 3, 2, 1, 0 and -1) and 2:2 ((UO{sub 2}){sub 2}H{sub j}L{sub 2} where j = 1, 0 and -1) complexes form, but the 1:2 complexes are the major species in a wide pH range. Thermodynamic parameters (formation constants, enthalpy and entropy of complexation) were determined by potentiometry and calorimetry. Data indicate that the complexation of U(VI) with HEDPA is exothermic, favored by the enthalpy of complexation. This is in contrast to the complexation of U(VI) with dicarboxylic acids in which the enthalpy term usually is unfavorable. Results from electrospray ionization mass spectrometry (ESI-MS) and {sup 31}P NMR have confirmed the presence of 1:1, 1:2 and 2:2 U(VI)-HEDPA complexes.
Date: January 24, 2007
Creator: Reed, W. A.; Rao, L.; Zanonato, P.; Garnov, A.; Powell, B. A. & Nash, K. L.
System: The UNT Digital Library
CP violation and rare decays (open access)

CP violation and rare decays

After a brief essay on the current state of particle physics and possible approaches to the opportunities that have presented themselves, the author summarizes the contributions to the Third Workshop on Physics and Detectors for DA{Phi}NE that deal with CP Violation and Rare Decays.
Date: January 24, 2000
Creator: Quigg, C.
System: The UNT Digital Library
CT imaging of two phase flow in fractured porous media (open access)

CT imaging of two phase flow in fractured porous media

This paper describes the design, construction, and preliminary results of an experiment that studies imbibition displacement in two fracture blocks. Three core configurations were constructed. The configurations are a compact core, a two-block system with a 1 mm spacer between the blocks, and a two-block system with no spacer. The blocks are sealed in epoxy so that saturation measurements can be made throughout the displacement experiments using a Computed Tomography (CT) scanner. Preliminary results are presented from a water/air experiment. These results suggest that it is incorrect to assume negligible capillary continuity between matrix blocks as is often done.
Date: January 24, 1996
Creator: Hughes, Richard G.; Brigham, William E. & Castanier, Louis M.
System: The UNT Digital Library
Decay properties of nuclei at the end of the periodic system (open access)

Decay properties of nuclei at the end of the periodic system

Recent studies of nuclear mass models show that it is essential to account for the Coulomb redistribution energy when calculating the nuclear potential energy in the heavy-element region. Results obtained by use of a mass model that includes Coulomb redistribution effects on analyzed. Q values of {alpha} and {beta} decay are calculated. Half-lives for {alpha} decay are estimated by use of the Viola-Seaborg systematics. For EC, {beta}{sup +} decay and {beta}{sup {minus}} decay, half-lives are calculated in a microscopic QRPA model. Calculated single-particle level structures in the heavy-element regions are presented. These indicate possible regions of isomers that would be unusually stable with respect to spontaneous fission and {alpha} decay. Finally, we discuss the implications of earlier extensive work on fission properties of nuclei in this region.
Date: January 24, 1992
Creator: Moeller, P. (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)) & Nix, J.R. (Los Alamos National Lab., NM (United States))
System: The UNT Digital Library