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Coherence and chaos in extended dynamical systems
Coherence, chaos, and pattern formation are characteristic elements of the nonequilibrium statistical mechanics controlling mesoscopic order and disorder in many-degree-of-freedom nonlinear dynamical systems. Competing length scales and/or time scales are the underlying microscopic driving forces for many of these aspects of ``complexity.`` We illustrate the basic concepts with some model examples of classical and quantum, ordered and disordered, nonlinear systems.
Date:
December 31, 1994
Creator:
Bishop, A. R.
Object Type:
Article
System:
The UNT Digital Library
Coherent V{sub 2}O{sub 3} precipitates in {alpha}-Al{sub 2}O{sub 3} co-implanted with vanadium and oxygen
The oxides of vanadium VO{sub 2} and V{sub 2}O{sub 3} are of fundamental and practical interest since they undergo structural phase transitions during which large variations in their optical and electronic properties are observed. In the present work, the authors report the formation of buried precipitates of V{sub 2}O{sub 3} in sapphire by ion implantation and thermal annealing. It was found that the co-implantation of oxygen and vanadium was required in order to form nanophase V{sub 2}O{sub 3} precipitates. Additionally, these precipitates, which formed only following an anneal of the co-implanted sample under reducing conditions, are coherent with the sapphire lattice. Two epitaxial relationships were observed: (0001)V{sub 2}O{sub 3}//(0001) {alpha}-Al{sub 2}O{sub 3} and (11--20)V{sub 2}O{sub 3}//(0001) {alpha}-Al{sub 2}O{sub 3}. This finding is in agreement with results obtained elsewhere for thin films of V{sub 2}O{sub 3} deposited on c-axis-oriented sapphire.
Date:
December 31, 1994
Creator:
Gea, L. A.; Boatner, L. A.; Budai, J. D. & Rankin, J.
Object Type:
Report
System:
The UNT Digital Library
Combined removal of SO{sub x} and NO{sub x} from flue gas using non-thermal plasma. [Quarterly] technical report, September 1--November 30, 1994
The SO{sub 2} removal efficiency was studied for concentration in the range of 333--3000 ppM (parts per million). Since the sulfur content of Illinois coal is high, the SO{sub 2} concentration in typical flue gas is in the high end of the range shown above. With high concentration of SO{sub 2} the removal efficiency decreases. However, the removal scales well with applied voltage, electrode length, and supply frequency. In this period the modeling of the process was also accomplished. The results show that a Townsend-type discharge is more efficient than a streamer type discharge in producing OH and 0 radicals. This explains why UV-irradiation helps the removal efficiency. The details are discussed in the report.
Date:
December 31, 1994
Creator:
Dhali, S.K.
Object Type:
Report
System:
The UNT Digital Library
Combustion of char-coal waste pellets for high efficiency and low NO{sub x}. Technical report, September 1--November 30, 1994
Illinois coals are prime candidates for use in Integrated Gasification Combined Cycle (IGCC) plants because of their high volatility and good char reactivity. In these plants, partial gasification of the coal in the presence of limestone eliminates the major portion of the sulfur species in the product gases, which are used as fuel for the topping cycle. The char produced is high in ash content, the major portion of which is calcium sulfide. It is also low in volatiles and of low density, compared to the parent coal. The economic success of the gasification route depends on the subsequent utilization of the residual char for raising steam for use in a Rankine cycle bottoming plant and/or preheating the air to the gasifier. Fluidized bed combustion of the char appears an attractive way of utilizing the char. Areas of concern in the fluidized bed combustion of the high ash, low volatility char are: attainment of high carbon conversion efficiencies; reduction of oxides of nitrogen emissions; reduction/elimination of corrosive chlorine species; reduction/elimination of sodium and other alkali species; and efficient usage of the calcium present in the ash to reduce sulfur compounds. The aim of the present project is to investigate ways …
Date:
December 31, 1994
Creator:
Rajan, S.
Object Type:
Report
System:
The UNT Digital Library
Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report No. 12, December 1, 1993--February 28, 1994
The NOXSO process is a dry, post-combustion flue gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from the flue gas of a coal-fired utility boiler. In the process, the SO{sub 2} is reduced to sulfur by-product and the NO{sub x} is reduced to nitrogen and oxygen. It is predicted that the process can economically remove 90% of the acid rain precursor gases from the flue gas stream in a retrofit or new facility. The objective of the NOXSO Demonstration Project is to design, construct, and operate a flue gas treatment system utilizing the NOXSO process. The effectiveness of the process will be demonstrated by achieving significant reductions in emissions of sulfur and nitrogen oxides. In addition, sufficient operating data will be obtained to confirm the process economics and provide a basis to guarantee performance on a commercial scale. The project is presently in the project definition and preliminary design phase. Data obtained during pilot plant testing which was completed on July 30, 1993 is being incorporated in the design of the commercial size plant. A suitable host site to demonstrate the NOXSO process on a commercial scale is …
Date:
December 31, 1994
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report No. 13, March 1, 1994--May 31, 1994
The NOXSO process is a dry, post-combustion flue gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from the flue gas of a coal-fired utility boiler. In the process, the SO{sub 2} is converted to a sulfur by-product and the NO{sub x} is converted to nitrogen and oxygen. It is predicted that the process can economically remove 90% of the acid rain precursor gases from the flue gas stream in a retrofit or new facility. The objective of the NOXSO Demonstration Project is to design, construct, and operate a flue gas treatment system utilizing the NOXSO process. The effectiveness of the process will be demonstrated by achieving significant reductions in emissions of sulfur and nitrogen oxides. In addition, sufficient operating data will be obtained to confirm the process economics and provide a basis to guarantee performance on a commercial scale. The project is presently in the project definition and preliminary design phase. Data obtained during pilot plant testing which was completed on July 30, 1993 is being incorporated in the design of the commercial size plant. A suitable host site to demonstrate the NOXSO process on a commercial scale …
Date:
December 31, 1994
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Commercial-scale demonstration of the Liquid Phase Methanol (LPMEOH{trademark}) process. Technical progress report number 2, July 1--September 30, 1994
The project involves the construction of a 260 tons-per-day (TPD) or 80,000 gallon per day methanol demonstration unit utilizing an existing coal-derived synthesis gas from Eastman. The new equipment consists of synthesis gas feed preparation and compression, liquid phase reactor and auxiliaries, product distillation, and utilities. The technology to be demonstrated was developed by Air Products in a DOE sponsored program that started in 1981. Originally tested at a small, DOE-owned experimental facility in LaPorte, Texas, the LPMEOH{trademark} process offers several advantages over current methods of making methanol. This liquid phase process suspends fine catalyst particles in an inert liquid, forming a slurry. The liquid dissipates heat from the chemical reaction away from the catalyst surface, protecting the catalyst and allowing the gas-to-methanol reaction to proceed at higher rates. The process is ideally suited to the type of gas produced by modern coal gasifiers. At the Eastman Chemical complex, the technology will be integrated with existing coal gasifiers to demonstrate the commercially important aspects of the operation of the LPMEOH{trademark} Process to produce methanol. A four-year demonstration will prove the commercial applicability of the process. An off-site product-use test program will prove the suitability of the methanol as a transportation …
Date:
December 31, 1994
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Comparison of bridged polysilsesquioxane xerogels prepared from methoxy- and ethoxy-silyl monomers
Hydrocarbon-bridged polysilsesquioxanes are prepared by the sol-gel polymerization of monomers with more than one trialkoxysilyl group attached directly to the bridging group by Si-C bonds. While the effects of varying the identity of the bridging group (length, rigidity, etc.), monomer concentration, and type of catalyst have been studied, the effect of different alkoxy ligands on the silicon atoms has not been investigated. For this study, 1, 6-- bis(triethoxysilyl)hexane 1 and 1, 6-bis(trimethoxysilyl)hexane 2 were polymerized under acidic and basic conditions in ethanol and methanol, respectively, and in tetrahydrofuran (THF). The resulting gels were processed to afford xerogels that were characterized by SEM, solid state {sup 13}C and {sup 29}Si Cross Polarization Magic Angle Spinning (CP MAS) NMR spectroscopy, and nitrogen sorption porosimetry.
Date:
December 31, 1994
Creator:
Loy, D. A.; Baugher, B.; Assink, R. A.; Prabakar, S. & Shea, K. J.
Object Type:
Article
System:
The UNT Digital Library
A comparison of NH{sub 3} point monitoring and diode laser based path integrated measurements
Measurements made using two different types of ammonia monitors during a two-month field study in the summer of 1994 are discussed. The first was a diode-laser based open path monitor designed for automated operation in an industrial environment. The second is a monitoring analyzer based on thermal decomposition of ammonia to NO and subsequent analysis by O{sub 3}-NO chemiluminescence. The two monitors provided consistent measurements of ammonia concentration during weeks of continuous unattended operation.
Date:
December 31, 1994
Creator:
Goldstein, N.; Richtsmeier, S. C.; Lee, J.; Bien, F.; Fetzer, G. J. & Groff, K. W.
Object Type:
Report
System:
The UNT Digital Library
A comparison of pressure compaction and diametral compression tests for determining granule strengths
Lightning strikes can cause structural damage, ignite flammable materials, and produce circuit malfunctions in missiles, aircraft, and ground systems. Lightning arrestor connectors (LACs) are used to divert harmful lightning energy away from these systems by providing less destructive breakdown paths. Ceramic granules in the size range of 150--200 {micro}m are used in LACs to provide physical and electrical separation of contacts (pins) from the surrounding metal web, and to control the voltage breakdown level. Pressure compaction (P-C) tests were used to characterize the strength of ceramic granules. When compaction data are plotted as relative density of the compact versus the compaction pressure two linear regions are generally observed. The intersection of these regions, which is known as the ``breakpoint,`` has been used as a semi-quantitative measure of granule strength. Comparisons were made between the P-C breakpoint and strengths of 150--200 {micro}m diameter ZnO, TiO{sub 2} (rutile), and lead magnesium niobate-lead titanate (PMN-PT) granules, where the strengths were determined by diametral compression (D-C) tests. At high compaction pressures the compliance of the die itself is significant and was accounted for in the analyses. Tests were conducted at different compaction rates, and with different aspect ratio compacts. High aspect ratios and loading …
Date:
December 31, 1994
Creator:
Glass, S.J. & Newton, C.
Object Type:
Article
System:
The UNT Digital Library
Comparison of rainfall sampling schemes using a calibrated stochastic rainfall generator
Accurate rainfall measurements are critical to river flow predictions. Areal and gauge rainfall measurements create different descriptions of the same storms. The purpose of this study is to characterize those differences. A stochastic rainfall generator was calibrated using an automatic search algorithm. Statistics describing several rainfall characteristics of interest were used in the error function. The calibrated model was then used to generate storms which were exhaustively sampled, sparsely sampled and sampled areally with 4 x 4 km grids. The sparsely sampled rainfall was also kriged to 4 x 4 km blocks. The differences between the four schemes were characterized by comparing statistics computed from each of the sampling methods. The possibility of predicting areal statistics from gauge statistics was explored. It was found that areally measured storms appeared to move more slowly, appeared larger, appeared less intense and have shallower intensity gradients.
Date:
December 31, 1994
Creator:
Welles, E.
Object Type:
Report
System:
The UNT Digital Library
Comparison of the activities of fine-particle size catalysts
The objectives of Sandia`s fine-particle size catalyst testing project are to evaluate and compare the activities of the fine-particle size catalysts being developed in DOE/PETCs Advanced Research Coal Liquefaction Program by using standard coal liquefaction test procedures. The standard procedures use Blind Canyon coal, phenanthrene as the reaction solvent, and a factorial experimental design with temperatures from 350{degrees}C to 400{degrees}C, reaction times from 20 to 60 minutes, and catalyst loadings up to 1 wt%. Catalytic activity is measured in terms of tetrahydrofuran conversion, heptane conversion, the amount of 9,10-dihydrophenanthrene in the product, and the gas yield. Several catalysts have been evaluated including a commercially available pyrite, a sulfated iron oxide from the University of Pittsburgh, and several preparations of 6-line ferrihydrites from Pacific Northwest Laboratories. Results have demonstrated that significant differences in activity can be detected among these catalysts.
Date:
December 31, 1994
Creator:
Stohl, F. V.; Diegert, K. V. & Goodnow, D. C.
Object Type:
Article
System:
The UNT Digital Library
Competitive ion kinetics in direct mass spectrometric organic speciation. 1994 Progress report
The experimental work on the gas phase proton affinity (PA) scale, discussed in some detail in last year`s Progress Report, will be completed within the next few weeks. Basically this effort involves the development of a precise and accurate interlocking ladder of relative PA`s derived from the temperature dependence of proton transfer equilibria incorporating a variety of reactant pairs using the technique of pulsed high pressure mass spectrometry (NIST has the only US facility). The PA subset under investigation was expanded from the original list to cover the region between CH{sub 3}CHO and (CH{sub 3}){sub 2}CO, which spans a PA range of approximately 12 kcal/mol. More than 300 separate equilibrium measurements have been carried out to date over the temperature range 240--395 C. The thermochemical region under study creates a bridge between the so-called upper and lower PA scales, and includes two primary reference standards, CH{sub 3}CHO and i-C{sub 4}H{sub 8}, with PA`s independently defined elsewhere via photoionization techniques.
Date:
December 31, 1994
Creator:
Sieck, L.W.
Object Type:
Report
System:
The UNT Digital Library
A comprehensive software system for image processing and programming. Final report
XVision is an example of a comprehensive software system dedicated to the processing of multidimensional scientific data. Because it is comprehensive it is necessarily complex. This design complexity is dealt with by considering XVision as nine overlapping software systems, their components and the required standards. The complexity seen by a user of XVision is minimized by the different interfaces providing access to the image processing routines as well as an interface to ease the incorporation of new routines. The XVision project has stressed the importance of having: (1) interfaces to accommodate users with differing preferences and backgrounds and (2) tools to support the programmer and the scientist. The result is a system that provides a framework for building a powerful research, education and development tool.
Date:
December 31, 1994
Creator:
Rasure, J.; Hallett, S. & Jordan, R.
Object Type:
Report
System:
The UNT Digital Library
A Compton scatter camera for spectral imaging of 0.5 to 3.0 MeV gamma rays
A prototype Compton scatter camera for imaging gamma rays has been built and tested. This camera addresses unique aspects of gamma-ray imaging at nuclear industrial sites, including gamma-ray energies in the 0.5 to 3.0 MeV range and polychromatic fields. Analytic models of camera efficiency, resolution and contaminating events are developed. The response of the camera bears strong similarity to emission computed tomography devices used in nuclear medicine. A direct Fourier based algorithm is developed to reconstruct two-dimensional images of measured gamma-ray fields. Iterative ART and MLE algorithms are also investigated. The point response of the camera to gamma rays of energies from 0.5 to 2.8 MeV is measured and compared to the analytic models. The direct reconstruction algorithm is at least ten times more efficient than the iterative algorithms are also investigated. The point response of the camera to gamma rays energies from 0.5 to 2.8 MeV is measured and compared to the analytic models. The direct reconstruction algorithm is at least ten times more efficient than the iterative algorithms and produces images that are, in general, of the same quality. Measured images of several phantoms are shown. Important results include angular resolutions as low as 4.4{degrees}, reproduction of phantom …
Date:
December 31, 1994
Creator:
Martin, J.B.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Computational and experimental studies of hydrodynamic instabilities and turbulent mixing: Review of VNIIEF efforts. Summary report
The report presents the basic results of some calculations, theoretical and experimental efforts in the study of Rayleigh-Taylor, Kelvin-Helmholtz, Richtmyer-Meshkov instabilities and the turbulent mixing which is caused by their evolution. Since the late forties the VNIIEF has been conducting these investigations. This report is based on the data which were published in different times in Russian and foreign journals. The first part of the report deals with calculations an theoretical techniques for the description of hydrodynamic instabilities applied currently, as well as with the results of several individual problems and their comparison with the experiment. These methods can be divided into two types: direct numerical simulation methods and phenomenological methods. The first type includes the regular 2D and 3D gasdynamical techniques as well as the techniques based on small perturbation approximation and on incompressible liquid approximation. The second type comprises the techniques based on various phenomenological turbulence models. The second part of the report describes the experimental methods and cites the experimental results of Rayleigh-Taylor and Richtmyer-Meskov instability studies as well as of turbulent mixing. The applied methods were based on thin-film gaseous models, on jelly models and liquid layer models. The research was done for plane and cylindrical …
Date:
December 31, 1994
Creator:
Andronov, V. A.; Zhidov, I. G.; Meskov, E. E.; Nevmerzhitskii, N. V.; Nikiforov, V. V.; Razin, A. N. et al.
Object Type:
Report
System:
The UNT Digital Library
Computational results for parallel unstructured mesh computations
The majority of finite element models in structural engineering are composed of unstructured meshes. These unstructured meshes are often very large and require significant computational resources; hence they are excellent candidates for massively parallel computation. Parallel solution of the sparse matrices that arise from such meshes has been studied heavily, and many good algorithms have been developed. Unfortunately, many of the other aspects of parallel unstructured mesh computation have gone largely ignored. The authors present a set of algorithms that allow the entire unstructured mesh computation process to execute in parallel -- including adaptive mesh refinement, equation reordering, mesh partitioning, and sparse linear system solution. They briefly describe these algorithms and state results regarding their running-time and performance. They then give results from the 512-processor Intel DELTA for a large-scale structural analysis problem. These results demonstrate that the new algorithms are scalable and efficient. The algorithms are able to achieve up to 2.2 gigaflops for this unstructured mesh problem.
Date:
December 31, 1994
Creator:
Jones, M. T. & Plassmann, P. E.
Object Type:
Report
System:
The UNT Digital Library
Computer simulation and capacity evaluation of Panama Canal alternatives
The Operating Characteristics and Capacity Evaluation (OCCE) Study was one of the components of a group of studies of future alternatives to the Panama Canal, sponsored by a study commission formed by the governments of Panama, the US and Japan. The basic tool in the conduct of the study was the Waterway Analysis Model (WAM), developed originally by the US Army Corps of Engineers for use on the US inland waterway system and adapted under OCCE for study of Panama Canal alternatives. The study synthesized the many alternative plans for the Canal proposed historically into four basic groups: High-Rise Lock Canal, Low-Rise Lock Canal, Sea-Level Canal and Status Quo Canal. For economy, the sea-level cases were based on, essentially, a single-lane canal, in conjunction with the status quo canal. Hydraulic and navigation studies indicted that to achieve safe navigation, tide gates or locks would be required to control currents that would otherwise be generated by the differences in tides between the two oceans. The alternatives studied in detail are illustrated in the body of the paper.
Date:
December 31, 1994
Creator:
Rosselli, A. T.; Bronzini, M. S. & Weekly, D. A.
Object Type:
Article
System:
The UNT Digital Library
Computerized accounting methods. Final report
This report summarizes the results of the research performed under the Task Order on computerized accounting methods in a period from 03 August to 31 December 1994. Computerized nuclear material accounting methods are analyzed and evaluated. Selected methods are implemented in a hardware-software complex developed as a prototype of the local network-based CONMIT system. This complex has been put into trial operation for test and evaluation of the selected methods at two selected ``Kurchatov Institute`` Russian Research Center (``KI`` RRC) nuclear facilities. Trial operation is carried out since the beginning of Initial Physical Inventory Taking in these facilities that was performed in November 1994. Operation of CONMIT prototype system was demonstrated in the middle of December 1994. Results of evaluation of CONMIT prototype system features and functioning under real operating conditions are considered. Conclusions are formulated on the ways of further development of computerized nuclear material accounting methods. The most important conclusion is a need to strengthen computer and information security features supported by the operating environment. Security provisions as well as other LANL Client/Server System approaches being developed by Los Alamos National Laboratory are recommended for selection of software and hardware components to be integrated into production version of …
Date:
December 31, 1994
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Concept for a super-clean super-efficient pressurized fluidized-bed combustion system
A paper study for a highly efficient, environmentally benign, coal-fired electric power generation system, is presented. This system falls in the category of pressurized fluidized-bed combustion (PFBC) systems which has been dubbed super-clean super-efficient PFBC`s. The system presented starts with the second-generation PFBC concept and adds on advanced gas turbine, a solid oxide fuel cell, a supercritical steam cycle, a second low-temperature rankine cycle which pulls energy from the steam condenser, and inlet air cooling. The thermodynamic efficiency of the system is calculated to be 61.8 percent based on higher heating value (HHV).
Date:
December 31, 1994
Creator:
Mollott, D.J. & Reed, M.
Object Type:
Article
System:
The UNT Digital Library
Condensed argon isentropic compression with ultrahigh magnetic field pressure: Results of the experiment. Post-shot report
The experiment on solid argon isentropic compression with MC-1 generator ultrahigh magnetic field pressure which was scheduled in VNIIEF-LANL subcontract, has initiated the condensed argon study at megabar pressures. The experiment has recorded the predicted argon compression by more than 5 times that, by the existing concepts, corresponds to 6 Mbar pressure. Thus, the main goals of the experiment were achieved: demonstration of the method`s possibilities and statement of the subsequent study. The isentropic compression device capabilities were shown, the basic characteristics of the isentropic compression and an initial parameters of the experimental facilities and techniques were defined, new information on the changed argon properties at 1 Mbar was obtained.
Date:
December 31, 1994
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Constitutive representation of damage development and healing in WIPP salt
There has been considerable interest in characterizing and modeling the constitutive behavior of rock salt with particular reference to long-term creep and creep failure. The interest is motivated by the projected use of excavated rooms in salt rock formations as repositories for nuclear waste. It is presumed that closure of those rooms by creep ultimately would encapsulate the waste material, resulting in its effective isolation. A continuum mechanics approach for treating damage healing is formulated as part of a constitutive model for describing coupled creep, fracture, and healing in rock salt. Formulation of the healing term is, described and the constitutive model is evaluated against experimental data of rock salt from the Waste Isolation Pilot Plant (WIPP) site. The results indicate that healing anistropy in WIPP salt can be modeled with an appropriate power-conjugate equivalent stress, kinetic equation, and evolution equation for damage healing.
Date:
December 31, 1994
Creator:
Chan, K. S.; Bodner, S. R.; Fossum, A. F. & Munson, D. E.
Object Type:
Article
System:
The UNT Digital Library
Construction and commissioning of the positron accumulator ring for the APS
The injector for the Advanced Photon Source (APS) incorporates a 450-MeV positron accumulator ring (PAR) to accumulate and damp positrons from the 60Hz linac during each cycle of the 2-Hz synchrotron. An overview of PAR hardware is presented. Commissioning of the PAR is well underway using electrons. Studies have produced a modified lattice model using three free parameters that agrees well with measurements. Principle problems are high leakage fields from the septum and ion trapping.
Date:
December 31, 1994
Creator:
Borland, M.
Object Type:
Article
System:
The UNT Digital Library
Controlling incipient oxidation of pyrite for improved rejection. Eighth quarterly technical progress report, July 1, 1994--September 30, 1994
The major objectives of this work are (1) to determine the Eh-pH conditions under which pyrite is stable, (2) to determine the mechanism of the initial stages of pyrite oxidation and (3) to determine if the semi-conducting properties of pyrite effects its oxidation behavior. It is known that moderate oxidation of pyrite produces a hydrophobic surface product. This hydrophobic product makes it extremely difficult to depress pyrite in coal flotation circuits. The eventual objective of this work is to prevent pyrite oxidation in order to better depress pyrite in coal flotation circuits. In this work clean, unoxidized pyrite surfaces are being produced by fracturing pyrite electrodes in an electrochemical cell. It has been shown that pyrite assumes a unique potential referred to as the ``stable potential`` at the instance it is fractured and that this potential is several hundred millivolts more negative than the steady state mixed potential of pyrite. It has also been shown that by holding the potential of pyrite at its stable potential during fracture, pyrite undergoes neither oxidation nor reduction. It has also been found that fresh pyrite surfaces created by fracture in an electrochemical begin to oxidize at potentials that are about 200 mV more …
Date:
December 31, 1994
Creator:
Yoon, R. H. & Richardson, P. E.
Object Type:
Report
System:
The UNT Digital Library