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EDI as a Treatment Module in Recycling Spent Rinse Waters (open access)

EDI as a Treatment Module in Recycling Spent Rinse Waters

Recycling of the spent rinse water discharged from the wet benches commonly used in semiconductor processing is one tactic for responding to the targets for water usage published in the 1997 National Technology Roadmap for Semiconductors (NTRS). Not only does the NTRS list a target that dramatically reduces total water usage/unit area of silicon manufactured by the industry in the future but for the years 2003 and beyond, the NTRS actually touts goals which would have semiconductor manufacturers drawing less water from a regional water supply per unit area of silicon manufactured than the quantity of ultrapure water (UPW) used in the production of that same silicon. Achieving this latter NTRS target strongly implies more widespread recycling of spent rinse waters at semiconductor manufacturing sites. In spite of the fact that, by most metrics, spent rinse waters are of much higher purity than incoming municipal waters, recycling of these spent rinse waters back into the UPW production plant is not a simple, straightforward task. The rub is that certain of the chemicals used in semiconductor manufacturing, and thus potentially present in trace concentrations (or more) in spent rinse waters, are not found in municipal water supplies and are not necessarily …
Date: August 11, 1999
Creator: Donovan, Robert P. & Morrison, Dennis J.
System: The UNT Digital Library
Low-defect reflective mask blanks for extreme ultraviolet lithography (open access)

Low-defect reflective mask blanks for extreme ultraviolet lithography

Extreme Ultraviolet Lithgraphy (EUVL) is an emerging technology for fabrication of sub-100 nm feature sizes on silicon, following the SIA roadmap well into the 21st century. The specific EUVL system described is a scanned, projection lithography system with a 4:1 reduction, using a laser plasma EUV source. The mask and all of the system optics are reflective, multilayer mirrors which function in the extreme ultraviolet at 13.4 nm wavelength. Since the masks are imaged to the wafer exposure plane, mask defects greater than 80% of the exposure plane CD (for 4:1 reduction) will in many cases render the mask useless, whereas intervening optics can have defects which are not a printing problem. For the 100 nm node, we must reduce defects to less than 0.01/cm&sup2; @ 80nm or larger to obtain acceptable mask production yields. We have succeeded in reducing the defects to less than 0.1/cm&sup2; for defects larger than 130 nm detected by visible light inspection tools, however our program goal is to achieve 0.01/cm&sup2; in the near future. More importantly though, we plan to have a detailed understanding of defect origination and the effect on multilayer growth in order to mitigate defects below the 10<sup>-2</sup>/cm&sup2; level on the …
Date: March 11, 1999
Creator: Burkhart, S. C.; Cerjarn, C.; Kearney, P.; Mirkarimi, P.; Walton, C. & Ray-Chaudhuri, A.
System: The UNT Digital Library
Ultrasonic characterization of synthetic soils for application to near surface geophysics (open access)

Ultrasonic characterization of synthetic soils for application to near surface geophysics

None
Date: November 11, 1999
Creator: Berge, P; Bonner, B P; Boro, C; Hardy, E; Ruddle, C & Trombino, C
System: The UNT Digital Library
Lessons Learned from the Puerto Rico Battery Energy Storage System (open access)

Lessons Learned from the Puerto Rico Battery Energy Storage System

The Puerto Rico Electric Power Authority (PREPA) installed a battery energy storage system in 1994 at a substation near San Juan, Puerto Rico. It was patterned after two other large energy storage systems operated by electric utilities in California and Germany. The Puerto Rico facility is presently the largest operating battery storage system in the world and has successfully provided frequency control, voltage regulation, and spinning reseme to the Caribbean island. The system further proved its usefulness to the PREPA network in the fall of 1998 in the aftermath of Hurricane Georges. However, the facility has suffered accelerated cell failures in the past year and PREPA is committed to restoring the plant to full capacity. This represents the first repowering of a large utility battery facility. PREPA and its vendors and contractors learned many valuable lessons during all phases of project development and operation, which are summarized in this paper.
Date: August 11, 1999
Creator: Boyes, John D.; De Anda, Mindi Farber & Torres, Wenceslao
System: The UNT Digital Library
Deep Levels in p- and n-type InGaAsN for High Efficiency Multi-Junction III-V Solar Cells (open access)

Deep Levels in p- and n-type InGaAsN for High Efficiency Multi-Junction III-V Solar Cells

Red Teaming is an advanced form of assessment that can be used to identify weaknesses in a variety of cyber systems. it is especially beneficial when the target system is still in development when designers can readily affect improvements. This paper discusses the red team analysis process and the author's experiences applying this process to five selected Information Technology Office (ITO) projects. Some detail of the overall methodology, summary results from the five projects, and lessons learned are contained within this paper.
Date: November 11, 1999
Creator: Allerman, Andrew A.; Jones, Eric D.; Kaplar, Robert J.; Kurtz, Steven R.; Kwon, Daewon & Ringel, Steven A.
System: The UNT Digital Library
First Lasing of a High-Gain Harmonic Generation Free-Electron Laser Experiment. (open access)

First Lasing of a High-Gain Harmonic Generation Free-Electron Laser Experiment.

We report on the first lasing of a high-gain harmonic generation (HGHG) free-electron laser (FEL). The experiment was conducted at the Accelerator Test Facility (ATF) at Brookhaven National Laboratory (BNL). This is a BNL experiment in collaboration with the Advanced Photon Source (APS) at Argonne National Laboratory. A preliminary measurement gives a high-gain harmonic generation (HGHG) pulse energy that is 2 x 10{sup 7} times larger than the spontaneous radiation, In a purely self-amplified spontaneous emission (SASE) mode of operation, the signal was measured as 10 times larger than the spontaneous radiation in the same distance ({approximately}2 m) through the same wiggler. This means the HGHG signal is 2 x 10{sup 6} times larger than the SASE signal. To obtain the same saturated output power by the SASE process, the radiator would have to be 3 times longer (6 m).
Date: September 11, 1999
Creator: Babzien, M.; Ben-Zvi, Ilan; Biedron, S. G.; DiMauro, L. F.; Douryan, A.; Galayda, J. N. et al.
System: The UNT Digital Library
Jahn-Teller splitting and Zeeman effect of acceptors in diamond. (open access)

Jahn-Teller splitting and Zeeman effect of acceptors in diamond.

Employing the high resolution of a 5+4 tandem Fabry-Perot interferometer, we discovered that {Delta}{prime}, the Raman active electronic transition between the spin-orbit split 1s(p{sub 3/2}): {Lambda}{sub 8} and 1s(P{sub 1/2}) {Lambda}{sub 7} acceptor ground states, is a doublet for a boron impurity in diamond with a clearly resolved spacing of 0.81 {+-} 0.15 cm{sup {minus}1}. The direct observation of a Stokes/anti-Stokes pair with 0.80 {+-} 0.04 cm{sup {minus}1} shift provides a striking confirmation that the lower 1s(p{sub 3/2}): {Lambda}{sub 8} ground state has experienced a splitting due to a static Jahn-Teller distortion. The Zeeman effect of {Delta}{prime} has been investigated with a magnetic field along several crystallographic directions. Theory of the Zeeman effect, formulated in terms of the symmetry of the substitutional acceptor and the Luttinger parameters of the valence band, allows quantitative predictions of the relative intensities of the Zeeman components in full agreement with experiments. The observation of transitions within the {Lambda}{sub 8} Zeeman multiplet, i.e., the Raman-electron-paramagnetic-resonances, is yet another novel feature to emerge from the present study. The investigation has also yielded g-factors characterizing the Zeeman multiplets.
Date: September 11, 1999
Creator: Anthony, T. R.; Grimsditch, M.; Kim, H.; Ramdas, A. K. & Rodriguez, S.
System: The UNT Digital Library
Effect of interior surface finish on the break-up of commercial shaped charge liners (open access)

Effect of interior surface finish on the break-up of commercial shaped charge liners

A series of experiments aimed at understanding the influence of the liner interior surface finish on the break-up of shaped charge jets has been completed. The experiments used a standard 81-mm shaped charge design, loaded with LX-14 high explosive; incorporating high-precision copper shaped charged liners. The results indicate that a significant reduction of jet break-up time occurs between a surface finish of 99.30 microinches and 375.65 microinches. Surface finishes of 4.78, 44.54 and 99.30 microinches produced significantly better ductility and associated break-up times than the 375.65-microinch finish. The baseline production process high-precision liners were measured to have an average surface finish of 44.54 microinches. The results show that for the shaped charge warhead geometry and explosive combination investigated, some care must be taken in respect to surface finish, but that very fine surface finishes do not significantly improve the jet ductility and associated break-up times.
Date: August 11, 1999
Creator: Baker, E L & Schwartz, A J
System: The UNT Digital Library
Development of small, fast reactor core designs using lead-based coolant. (open access)

Development of small, fast reactor core designs using lead-based coolant.

A variety of small (100 MWe) fast reactor core designs are developed, these include compact configurations, long-lived (15-year fuel lifetime) cores, and derated, natural circulation designs. Trade studies are described which identify key core design issues for lead-based coolant systems. Performance parameters and reactivity feedback coefficients are compared for lead-bismuth eutectic (LBE) and sodium-cooled cores of consistent design. The results of these studies indicate that the superior neutron reflection capability of lead alloys reduces the enrichment and burnup swing compared to conventional sodium-cooled systems; however, the discharge fluence is significantly increased. The size requirement for long-lived systems is constrained by reactivity loss considerations, not fuel burnup or fluence limits. The derated lead-alloy cooled natural circulation cores require a core volume roughly eight times greater than conventional compact systems. In general, reactivity coefficients important for passive safety performance are less favorable for the larger, derated configurations.
Date: June 11, 1999
Creator: Cahalan, J. E.; Hill, R. N.; Khalil, H. S. & Wade, D. C.
System: The UNT Digital Library
Steam generator mock-up for assessment of inservice inspection technology. (open access)

Steam generator mock-up for assessment of inservice inspection technology.

A steam generator mock-up has been assembled for round-robin studies of the effectiveness of currently practiced inservice inspection (ISI) technology for detection of current-day flaws. The mock-up will also be used to evaluate emerging inspection technologies. The 3.66-m (12-ft.)-tall mock-up contains 400 tube openings, each consisting of 9 test sections that can be used to simulate current-day field-induced flaws and artifacts. Included in the mock-up are simulations of tube support plate (TSP) intersections and the tube sheet (TS). Cracks are present at the TSP, TS, and in the free span sections of the mock-up. For initial evaluation of the round-robin results, various eddy current methods, as well as multivariate models for data analysis techniques, are being used to estimate the depth and length of defects in the mock-up. To ensure that the round-robin is carried out with procedures as close as possible to those implemented in the field, input was obtained from industry experts on the protocol and procedures to be used for the exercise. One initial assembly of the mock-up with a limited number of flaws and artifact has been completed and tested. A second completed configuration with additional flaw and artifacts simulations will be used for the round-robin.
Date: September 11, 1999
Creator: Bakhtiari, S.; Kupperman, D. S. & Muscara, J.
System: The UNT Digital Library
Phosphate ceramic solidification and stabilization of cesium-containing crystalline silicotitanate resins. (open access)

Phosphate ceramic solidification and stabilization of cesium-containing crystalline silicotitanate resins.

This paper reports on the fabrication and testing of magnesium potassium phosphate (MKP)-bonded cesium-loaded crystalline silicotitanate (CST) resins. Typical waste loading of CST resins in the final waste forms was 50 wt.%. Physical and chemical characterization of the MKP materials has shown them to be physically, chemically, and mineralogically stable. Long-term durability studies (using the AN 16.1 standard test) showed a leachability index of {approx}18 for cesium in the phosphate matrix when exposed to deionized water under ambient and elevated temperatures. Leaching of cesium was somewhat higher than in glass waste forms as per PCT and MCC-1 tests. MKP-based final waste forms showed no significant weight changes after exposure to aqueous media for {approx}90 days, indicating the highly insoluble nature of the phosphate matrix. In addition, durability of the CST-MKP waste forms was further established by freeze-thaw cycling tests.
Date: May 11, 1999
Creator: Langton, C. A.
System: The UNT Digital Library
Elasticity of Tantalum to 105 Gpa using a stress and angle-resolved x-ray diffraction (open access)

Elasticity of Tantalum to 105 Gpa using a stress and angle-resolved x-ray diffraction

Determining the mechanical properties such as elastic constants of metals at Mbar pressures has been a difficult task in experiment. Following the development of anisotropic elastic theory by Singh et al. [l], Mao et a1.[2] have recently developed a novel experimental technique to determine the elastic constants of Fe by using the stress and energy-dispersive x-ray diffraction (SEX). In this paper, we present an improved complementary technique, stress and angle-resolved x-ray diffraction (SAX), which we have applied to determine the elastic constants of tantalum to 105 GPa. The extrapolation of the tantalum elastic data shows an excellent agreement with the low-pressure ultrasonic data [3]. We also discuss the improvement of this SAX method over the previous SEX. [elastic constant, anisotropic elastic theory, angle-dispersive synchrotron x-ray diffraction, mechanical properties]
Date: August 11, 1999
Creator: Cynn, H. & Yoo, C. S.
System: The UNT Digital Library
Multi-Exciter Vibroacoustic Simulation of Hypersonic Flight Vibration (open access)

Multi-Exciter Vibroacoustic Simulation of Hypersonic Flight Vibration

Many aerospace structures must survive severe high frequency, hypersonic, random vibration during their flights. The random vibrations are generated by the turbulent boundary layer developed along the exterior of the structures during flight. These environments have not been simulated very well in the past using a fixed-based, single exciter input with an upper frequency range of 2 kHz. This study investigates the possibility of using acoustic ardor independently controlled multiple exciters to more accurately simulate hypersonic flight vibration. The test configuration, equipment, and methodology are described. Comparisons with actual flight measurements and previous single exciter simulations are also presented.
Date: November 11, 1999
Creator: GREGORY,DANNY LYNN; CAP,JEROME S.; TOGAMI,THOMAS C.; NUSSER,MICHAEL A. & HOLLINGSHEAD,JAMES RONALD
System: The UNT Digital Library
Capital requirements and fuel-cycle energy and emissions impacts of potential PNGV fuels. (open access)

Capital requirements and fuel-cycle energy and emissions impacts of potential PNGV fuels.

Our study reveals that supplying gasoline-equivalent demand for the low-market-share scenario requires a capital investment of less than $40 billion for all fuels except H{sub 2}, which will require a total cumulative investment of $150 billion. By contrast, cumulative capital investments under the high-market-share scenario are $50 billion for LNG, $90 billion for ethanol, $100 billion for methanol, $160 billion for CNG and DME, and $560 billion for H{sub 2}. Although these substantial capital requirements are spread over many years, their magnitude could pose a challenge to the widespread introduction of 3X vehicles. Fossil fuel use by US light-duty vehicles declines significantly with introduction of 3X vehicles because of fuel-efficiency improvements for 3X vehicles and because of fuel substitution (which applies to the nonpetroleum-fueled alternatives). Petroleum use for light-duty vehicles in 2030 is reduced by as much as 45% relative to the reference scenario. GHG emissions follow a similar pattern. Total GHG emissions decline by 25-30% with most of the propulsion system/fuel alternatives. For those using renewable fuels (i.e., ethanol and H{sub 2} from solar energy), GHG emissions drop by 33% (H{sub 2}) and 45% (ethanol). Among urban air pollutants, urban NOX emissions decline slightly for 3X vehicles using CIDI …
Date: March 11, 1999
Creator: Johnson, L.; Mintz, M.; Singh, M.; Stork, K.; Vyas, A. & Wang, M.
System: The UNT Digital Library
Inclusive jets at the Tevatron (open access)

Inclusive jets at the Tevatron

Results are presented for the inclusive jet cross section versus jet E{sub T} in p-{bar p} collisions at {radical}s = 1.8 TeV as measured by the CDF and D0 detectors at Fermilab's Tevatron collider. The data are compared to next-to-leading-order QCD predictions using different input parton distribution functions. The ratio of inclusive jet cross sections at {radical}s = 0.63 TeV and {radical}s = 1.8 TeV, versus jet {chi}{sub T}, is also presented and compared to QCD predictions.
Date: November 11, 1999
Creator: Seidel, S.
System: The UNT Digital Library
A new molecular solid phase of carbon dioxide at high pressure and temperature (open access)

A new molecular solid phase of carbon dioxide at high pressure and temperature

We report the discovery of a new high-pressure molecular phase of carbon dioxide. The new polymorph, CO{sub 2} -IV, is formed by heating the high-pressure orthorhombic phase III to temperatures above 1000K at pressures between 12 and 33GPa. Analysis of the Raman spectrum of the new phase suggests a structure lacking inversion symmetry.
Date: August 11, 1999
Creator: Cynn, H.; Iota, V. & Yoo, C. S.
System: The UNT Digital Library
The intermediate silicon layers space Fframe (open access)

The intermediate silicon layers space Fframe

The Intermediate Silicon Layers (ISL) detector is being built as part of the Collider Detector at Fermilab (CDF) upgrades for the run II operation of Tevatron. The ISL Space Frame (SF) is a structure that defines the location of the ISL detectors, supports the micro-vertex silicon trackers (SVXII, L00) as well as the beryllium beam pipe. The SF design, project and construction is challenging due to the precision and mechanical stability requirements that must be achieved using a minimum amount of material. The SF is a high precision light structure made in carbon fiber designed and built at the INFN Pisa and shipped at Fermilab in summer 1999. In this contribution we describe in detail the SF construction phase and the accuracy obtained.
Date: November 11, 1999
Creator: Basti, A.; Bedeschi, F.; Demina, R.; Gaggelli, A. & Goldstein, J.
System: The UNT Digital Library
Experimental and ab Initio Investigations of the Kinetics of the Reaction of H Atoms with H2S (open access)

Experimental and ab Initio Investigations of the Kinetics of the Reaction of H Atoms with H2S

Article on experimental and ab initio investigations of the kinetics of the reaction of H atoms with H2S.
Date: June 11, 1999
Creator: Peng, Jingping; Hu, Xiaohua & Marshall, Paul
System: The UNT Digital Library
Laser-induced breakdown system for colloid characterization in dilute aqueous suspensions (open access)

Laser-induced breakdown system for colloid characterization in dilute aqueous suspensions

Detection and sizing of colloids by acoustic detection of laser-induced breakdown and elemental analysis of colloids by laser-induced breakdown spectroscopy are investigated in dilute aqueous suspensions. Development and testing of the methods are performed with standard polystyrene suspensions and prepared suspensions of defined composition and particle size. Application of the methods to analysis of field and laboratory samples is discussed. Am atomic emission lines are observed by laser-induced breakdown spectroscopy of an Am hydroxycarbonate suspension.
Date: August 11, 1999
Creator: Brachmann, A.; Mihardja, S.; Palmer, C. E. A. & Wruck, D. A.
System: The UNT Digital Library
Fabrication of Test Tubes for Coal Ash Corrosion Testing (open access)

Fabrication of Test Tubes for Coal Ash Corrosion Testing

This paper deals with the fabrication of tube sections of four alloys for incorporating into test sections to be assembled by Babcock & Wilcox (B&W) for installation at Ohio Edison Power, Niles Plant. The primary purpose of the installation was to determine the corrosion behavior of ten different alloys for flue gas corrosion. Ohio Edison Power, Niles Plant is burning an Ohio coal containing approximately 3.4% S (dry basis) and approximately 0.4% alkali which causes chronic coal ash corrosion of the unit�s superheater tubing. The 2.5-in.-OD x 0.4in.-wall x 6-in-long sections of four alloys {type 304H coated with Fe<sub>3</sub>Al alloy FAS [developed at the Oak Ridge National Laboratory (ORNL)], 310 + Ta, modified 800H, and Thermie alloy} were fabricated at ORNL. Each alloy tubing was characterized in terms of chemical analysis and microstructure. The machined tubes of each of the alloys were inspected and shipped on time for incorporation into the test loop fabricated at B&W. Among the alloys fabricated, Thermie was the hardest to extrude and machine.
Date: May 11, 1999
Creator: Johnson, R.; Judkins, R. R.; Sikka, V. K.; Swindeman, R. W. & Wright, I. G.
System: The UNT Digital Library
Two and Three-Electrode Impedance Studies on 18650 Li-Ion Cells (open access)

Two and Three-Electrode Impedance Studies on 18650 Li-Ion Cells

Two and three electrode impedance measurements were made on 18650 Li-ion cells at different QB temperatures ranging from 35 C to {minus}40 C. The ohmic resistance of the cell is nearly constant the temperature range studied although the total cell impedance increases by an order of magnitude in the same temperature range. In contrast to what is commonly believed, we show from our three-electrode impedance results that, the increase in cell impedance comes mostly from the cathode and not from the anode. Further, the anode and cathode contribute to both the impedance loops (in the NyQuist plot).
Date: August 11, 1999
Creator: Nagasubramanian, Ganesan
System: The UNT Digital Library
Automatic Mesh Coarsening for Discrete Ordinates Codes (open access)

Automatic Mesh Coarsening for Discrete Ordinates Codes

This paper describes the use of a ''mesh potential'' function for automatic coarsening of meshes in discrete ordinates neutral particle transport codes. For many transport calculations, a user may find it helpful to have the code determine a ''good'' neutronics mesh. The complexity of a problem involving millions of mesh cells, dozens of materials, and many energy groups makes it difficult to determine an adequate level of mesh refinement with a minimum number of cells. A method has been implemented in PARTISN (Parallel Time-dependent SN) to calculate a ''mesh potential'' in each original cell of a problem, and use this information to determine the maximum coarseness allowed in the mesh while maintaining accuracy in the solution. Results are presented for a simple x-y-z fuel/control/reflector problem.
Date: March 11, 1999
Creator: Turner, Scott A.
System: The UNT Digital Library
An Extension of the Krieger-Li-Iafrate Approximation to the Optimized-Effective-Potential Method (open access)

An Extension of the Krieger-Li-Iafrate Approximation to the Optimized-Effective-Potential Method

The Krieger-Li-Iafrate approximation can be expressed as the zeroth order result of an unstable iterative method for solving the integral equation form of the optimized-effective-potential method. By pre-conditioning the iterate a first order correction can be obtained which recovers the bulk of quantal oscillations missing in the zeroth order approximation. A comparison of calculated total energies are given with Krieger-Li-Iafrate, Local Density Functional, and Hyper-Hartree-Fock results for non-relativistic atoms and ions.
Date: November 11, 1999
Creator: Wilson, B.G.
System: The UNT Digital Library
Transport, Growth Mechanisms, and Material Quality in GaN Epitaxial Lateral Overgrowth (open access)

Transport, Growth Mechanisms, and Material Quality in GaN Epitaxial Lateral Overgrowth

Growth kinetics, mechanisms, and material quality in GaN epitaxial lateral over-growth (ELO) were examined using a single mask of systematically varied patterns. A 2-D gas phase reaction/diffusion model describes how transport of the Ga precursor to the growth surface enhances the lateral rate in the early stages of growth. In agreement with SEM studies of truncated growth runs, the model also predicts the dramatic decrease in the lateral rate that occurs as GaN over-growth reduces the exposed area of the mask. At the point of convergence, a step-flow coalescence mechanism is observed to fill in the area between lateral growth-fronts. This alternative growth mode in which a secondary growth of GaN is nucleated along a single convergence line, may be responsible for producing smooth films observed to have uniform cathodoluminescence (CL) when using 1{micro}m nucleation zones. Although emission is comprised of both UV ({approximately}365nm) and yellow ({approximately}550nm) components, the spectra suggest these films have reduced concentrations of threading dislocations normally associated with non-radiative recombination centers and defects known to accompany growth-front convergence lines.
Date: January 11, 1999
Creator: Baca, Albert G.; Bartram, M. E.; Coltrin, M. E.; Crawford, M. H.; Han, J.; Missert, N. et al.
System: The UNT Digital Library