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Articles 293791 - 293820 of 303988
Full-Text Articles in Physical Sciences and Mathematics
A Preliminary Bibliography And Lake Index Of The Inland Mineral Waters Of The World, D. B. Mccarraher
A Preliminary Bibliography And Lake Index Of The Inland Mineral Waters Of The World, D. B. Mccarraher
Nebraska Game and Parks Commission: Staff Research Publications
This preliminary- bibliography and lake index has been prepared by the author on the basis of information available in the Office of Limnology, Hastings College, Nebraska. Although all source material available there has been searched, it is recognized that many papers, especially those published in regional languages may have been left out. Readers are requested to point out such omissions and any inaccuracies that require correction.
This preliminary bibliography will be circulated among specialists in the subject for corrections to the citations and for suggested additions to the list. It is planned that the paper will then be revised to …
The Relation Between Soil Characteristics, Water Movement And Nitrate Contamination Of Ground Water, Grant W. Thomas, Matthew Mcmahon
The Relation Between Soil Characteristics, Water Movement And Nitrate Contamination Of Ground Water, Grant W. Thomas, Matthew Mcmahon
KWRRI Research Reports
Soils from several areas in Kentucky were placed in columns and leached with Ca(NO3)2. Subsoils high in iron oxide were found to retard the leaching of nitrate very significantly. In other soils, the nitrate moved through as fast as or slightly faster than the water.
Field application of nitrogen to corn was most efficient when done in the spring or summer near the time that the corn takes it up. The one exception to this was a red soil, where fall application of nitrogen resulted in little loss due to the retarding effect mentioned in the …
A Mathmatical Model Of Primary Productivity And Limnological Patterns In Lake Mead, Lorne G. Everett
A Mathmatical Model Of Primary Productivity And Limnological Patterns In Lake Mead, Lorne G. Everett
Publications (WR)
The temporal and spatial changes in chemical and biological properties of Lake Mead have been investigated, thereby indicating the sources of water pollution and the time of highest pollution potential. Planktonic organisms have been shown to indicate the presence of water problems. Macro- and micro-nutrient analyses have shown that primary productivity is not inhibited by limiting concentrations. A mathematical model has been developed, tested with one set of independent data, and shown worthy of management utility. Although the model works very well for the Lake Mead area, the physical reality of the Multiple Linear Regression equation should be tested on …
New Method For Generating Density Expansions, John D. Ramshaw
New Method For Generating Density Expansions, John D. Ramshaw
Physics Faculty Publications and Presentations
The calculus of finite differences is used to develop a new method for expressing the thermodynamic limit of a reasonably arbitrary statistical?mechanical average as a power series in the number density ?. The method is simple, straightforward, and purely analytic: it involves no intermediate expansion in powers of the activity and it avoids the use of graph theory. Moreover, the method is developed independently of the prescription for computing the statistical average, a fact which lends to the results an especially wide range of applicability. In particular, these results may be used in classical or quantum statistical mechanics, for intermolecular …
Lasing Conditions Of Elemental Sulfur In A Gas Discharge, David E. Egbert
Lasing Conditions Of Elemental Sulfur In A Gas Discharge, David E. Egbert
Theses and Dissertations
The partial pressures from heated sulfur crystals and helium, and sulfur and nitrogen required for ionic sulfur laser action in a gas discharge were determined. Previous work with sulfur lasers is reviewed and population inversion mechanisms are presented for the ionic sulfur laser lines. Possible excitation mechanisms are presented for both electron and ion or atomic collision excitation. Transition diagrams for all the known ionic sulfur laser transitions and an approximate potential energy curve for the diatomic sulfur molecule are presented. Laser action was achieved only when a spark gap pulser was used with a laser tube especially designed to …
Health Status Of Emergency Department Patients, Marjean J. Horning
Health Status Of Emergency Department Patients, Marjean J. Horning
Loma Linda University Electronic Theses, Dissertations & Projects
The purpose of this study was to help nursing develop a comprehensive care system for patients in selected emergency departments. To develop such a system, it was necessary to know the characteristics of and the health needs of that population.
The problem of this study was to describe the characteristics and health needs of patients in selected emergency departments.
Patients were interviewed using the Kisch Health Status Proxy (KHSP) and the Health Habits Inventory (HHI) as a guide. The KHSP listed acute and chronic conditions that an individual experienced. It gave a numerical score which rated the respondent in good, …
Magnetic Nonequivalence In Higher Alkyl Groups, Philip Anthony Reitano
Magnetic Nonequivalence In Higher Alkyl Groups, Philip Anthony Reitano
Masters Theses
The phenomenon of magnetic nonequivalence has been growing in recent years. Unequal populations of the various conformers in such molecules are normally accepted as the cause of nonequivalence, but nuclei which are stereochemically nonequivalent are not necessarily magnetically nonequivalent. This nonequivalence has been demonstrated for molecules of the type ABDC8CHR1R2, where R + H, F, and Me. Although in principle the effect is quite general this has not been previously observed in "freely rotating" systems for groups larger than methyl. The role of steric factors, the size of the substituents and the distances between …
X-Ray Diffraction Studies On Liquids At Very High Pressures Along The Melting Curve Ii. Sodium, Keith H. Brown, J. Dean Barnett
X-Ray Diffraction Studies On Liquids At Very High Pressures Along The Melting Curve Ii. Sodium, Keith H. Brown, J. Dean Barnett
Faculty Publications
Coherent x-ray diffraction patterns for liquid Na have been extracted from measured patterns at 0.5, 7.5, 17, and 43 kbar along the melting curve. The experimentally determined liquid structure factor and resulting radial distribution function are given at each pressure. The position of the principal x-ray intensity peak is reproducible to within 0.5% and shows shifts of the order of 12%. The resulting nearest neighbor distance in the radial distribution function also shifts 12% but is reproducible only to approximately 2%. The distribution functions obtained at points along the melting curve suggest a simple dimensional compression or scaling; however, a …
X-Ray Diffraction Studies On Liquids At Very High Pressures Along The Melting Curve. I. Methods And Techniques, Keith H. Brown, J. Dean Barnett
X-Ray Diffraction Studies On Liquids At Very High Pressures Along The Melting Curve. I. Methods And Techniques, Keith H. Brown, J. Dean Barnett
Faculty Publications
A technique using the tetrahedral anvil high-pressure x-ray system has been developed to extract coherent x-ray intensity patterns of liquids near melting from measured scattering curves in the presence of high-background counts. Radial distribution functions for liquids along the melting curve to pressures of at least 50 kbar can be obtained. At each pressure scattering curves are recorded for the liquid and solid on opposite sides of the melting curve and a subtraction is made to eliminate background and incoherent scattering. Theoretical estimates of the thermal diffuse scattering from the solid are added to the appropriately corrected difference patterns to …
Measurements Of The Mössbauer Fraction In Chromium, B. Frederick Brace Jr.
Measurements Of The Mössbauer Fraction In Chromium, B. Frederick Brace Jr.
Dissertations and Theses
Precision measurements of the Mossbauer fraction of Fe57 in chromium were made using the black absorber technique over a range of temperatures from 78K to 792K. Because of uncertainty in corrections at high temperatures, only the data collected from 78K to 600K was used in analyzing the results.
The f values were analyzed in terms of a Debye approximmation. This analysis of the data yielded a theoretical fit which was based on two adjustable parameters (a Debye temperature of 438K and an anharmonicity parameter of 2 x 10-4K-1).
The f measurements were also analyzed using a …
Raman Scattering From Zns Polytypes, J. Schneider, Roger D. Kirby
Raman Scattering From Zns Polytypes, J. Schneider, Roger D. Kirby
Roger Kirby Publications
The Raman spectra of the 2H and 4H structures of ZnS have been measured between room temperature and 60 K, and compared with the spectra from zinc blende ZnS. The observed phonons in each case are in good agreement with those expected from the known structural differences.
Frenkel Defects In Alkali Halides, Paul Schulze, John Hardy
Frenkel Defects In Alkali Halides, Paul Schulze, John Hardy
John R. Hardy Papers
The method of lattice statics and the deformation dipole model have been applied to Frenkel defects in ionic crystals. For isolated interstitials, all short-ranged repulsive and Coulomb-defect host-lattice ion forces were evaluated at the relaxed configuration. The zero-order Coulomb force was allowed to act on the remainder of the host-lattice ions past first neighbors. We have calculated Frenkel-pair formation energies, ionic displacements, and ionic polarizations in the twelve Na, K, Rb halides. Our results show over all that, in ionic crystals of the rocksalt structure, Schottky defect pairs are more likely to be present than Frenkel defect pairs.
Mössbauer Studies Of Electrostatic Hyperfine Interactions In 238U, 236U, And 234U, Joyce Anne Monard
Mössbauer Studies Of Electrostatic Hyperfine Interactions In 238U, 236U, And 234U, Joyce Anne Monard
Doctoral Dissertations
The nuclear gamma resonance (NGR) for 238U, 236U, and 234U in the compound (UO2) Rb (NO3)3 has been established at 4.2°K following the alpha decay of PuO2 sources. The ratios of the electric quadrupole moments of these isotopes have been determined and the electric field gradient at the uranium site has been calculated from the data. The isomer shift in 234U has been measured for both PuO2 and PuA14 sources and the change in nuclear radius between the excited and the ground state has been calculated.
Terminal Talk - The Wofford Connection - August 1972, Wofford College Computer Center
Terminal Talk - The Wofford Connection - August 1972, Wofford College Computer Center
Terminal Talk
No abstract provided.
Principles Of Control Theory As Applied To A Thermostat, Joseph Peter Stidham
Principles Of Control Theory As Applied To A Thermostat, Joseph Peter Stidham
Master's Theses
The recent development of solid state electronics has opened new possibilities in instrumentation design. One development has been the availability of compact, low cost, high gain, D. C. amplifiers which can be used in the design and construction of sensitive laboratory instruments (11). Using these amplifiers a thermostat capable of precise control can be constructed and its performance compared with the performance expected by an analysis of the closed loop control equations.
Nuclear-Magnetic-Resonance Study Of Co2+ In Cds, David C. Look, Donald R. Locker
Nuclear-Magnetic-Resonance Study Of Co2+ In Cds, David C. Look, Donald R. Locker
Physics Faculty Publications
Nuclear spin-lattice relaxation times, T1, have been measured over a temperature range T=(1.1-300) °K and frequency range ν=2-15 MHz in a single crystal of CdS doped with 13-ppm cobalt. Minima in T1 vs T are observed, and absolute values of the effective electron relaxation time, τe, may be calculated at the temperatures of the minima, e.g., at 14 °K, τe=8.0×10-8 sec. At low temperatures, T≲5 °K, τe is dominated by a resonant Orbach process involving the two ground-state Kramers doublets (S=±3/2 and S=±1/2) which, according to our measurements, are split by …
Tunellite, A New Hydrous Strontium Borate From The Sarikaya Borate Deposits In Turkey, Orhan Baysal
Tunellite, A New Hydrous Strontium Borate From The Sarikaya Borate Deposits In Turkey, Orhan Baysal
Bulletin of the Mineral Research and Exploration
No abstract provided.
Deği̇şken Frekansli İ.P. Metodunda, Aşiri Geri̇li̇mi̇n Reel Ve İmaji̇ner Bi̇leşenleri̇nden İsti̇fade İle Yan Kayaç Anomali̇leri̇ni̇n Sülfürlü Mi̇neral Yataklarinin Anomali̇leri̇nden Ayrilmasi*, Akın Gökişik
Bulletin of the Mineral Research and Exploration
No abstract provided.
Deni̇z Hukukundaki̇ Yeni̇ Geli̇şmeler Ve Madenci̇li̇kle İli̇şki̇si̇*, Selçuk Demi̇rsoy
Deni̇z Hukukundaki̇ Yeni̇ Geli̇şmeler Ve Madenci̇li̇kle İli̇şki̇si̇*, Selçuk Demi̇rsoy
Bulletin of the Mineral Research and Exploration
No abstract provided.
Eikonal Approximation For Coupled Equations For Multichannel Scattering, Rung T. Ling, Joseph C.Y. Chen, Jerry Peacher, Kenneth M. Watson
Eikonal Approximation For Coupled Equations For Multichannel Scattering, Rung T. Ling, Joseph C.Y. Chen, Jerry Peacher, Kenneth M. Watson
Physics Faculty Research & Creative Works
It is well known that the Glauber approximation for scattering amplitudes is obtained by applying the eikonal approximation to the Fourier transform of the transition operator. The eikonal approximation can also be applied to the coupled equations of scattering obtained by the expansion of the state function in terms of a suitable set of functions. The scattering amplitude can thus be obtained by solving the set of eikonal coupled equations. The latter approach is analyzed for a special class of channel-coupling potentials. The first-order approximation to the derived eikonal coupled equations is the eikonal Born approximation. Numerical illustrations in this …
A Study Of The (3He, N) Reaction At 25 Mev, Mark Bentley Greenfield
A Study Of The (3He, N) Reaction At 25 Mev, Mark Bentley Greenfield
Doctoral Dissertations
Energy spectra of neutrons from the 12C (3He, n)140; 27A1(3He, n)29P; 28Si(3He, n)30S; and 58,60,62Ni(3He, n)60,62,64Zn reactions have been measured at 25 MeV incident 3He energy using time-of-flight techniques. An overall energy resolution of about 1 percent for detection of 10-35 MeV neutrons provided accurate determinations of level excitations. Differential cross sections were extracted for many two particle states with up to 10 MeV excitation in the residual nuclei. By varying the beam incident angle and leaving the flight path somewhat …
Location Of Solution Channels And Sinkholes At Dam Sites And Backwater Areas By Seismic Methods: Part Ii, Vincent P. Drnevich, D. Raghu
Location Of Solution Channels And Sinkholes At Dam Sites And Backwater Areas By Seismic Methods: Part Ii, Vincent P. Drnevich, D. Raghu
KWRRI Research Reports
Four seismic field methods and a laboratory method are used to determine shear wave propagation velocities and shear moduli for two sites. The four seismic methods are: standard seismic refraction survey, down hole shooting refraction survey, transient Rayleigh wave survey, and crosshole shooting survey. A torsional resonant column apparatus was used for the laboratory tests. The cross hole shooting method gave the best results because direct measurements were made. Criteria for using this method are given. Methods which measure compression wave velocity give inconsistent results because the conversion to shear wave velocity is very sensitive to Poisson's ratio. Laboratory tests …
Location Of Solution Channels And Sinkholes At Dam Sites And Backwater Areas By Seismic Methods: Part I, Vincent P. Drnevich, S. R. Smith, E. P. Cleveland
Location Of Solution Channels And Sinkholes At Dam Sites And Backwater Areas By Seismic Methods: Part I, Vincent P. Drnevich, S. R. Smith, E. P. Cleveland
KWRRI Research Reports
The basic concepts associated with the sledge hammer seismic refraction survey are reviewed and a modified version called down hole shooting is discussed. The latter method has distinct advantages for rock surface profiling. These include: calibration at the end points of the survey, measurement of vertical wave propagation velocities directly, and having a refracted wave ray path for almost the entire survey length.
The down hole shooting seismic refraction survey has been simulated with the digital computer. The method can handle any shaped rock surface profile and generates corresponding travel time curves for the forward and reverse profile surveys. This …
Studies Of The Potential Curve Crossing Problem Ii. General Theory And A Model For Close Crossings, John B. Delos, W. R. Thorson
Studies Of The Potential Curve Crossing Problem Ii. General Theory And A Model For Close Crossings, John B. Delos, W. R. Thorson
Arts & Sciences Articles
A unified formal treatment of the two-state potential-curve-crossing problem in atomic collision theory is presented, and the case of close crossings analyzed in detail. A complete solution for this case, including necessary computations, is given using a suitable generalization of the linear model originally suggested by Landau, Zener, and Stueckelberg. Our solution is based upon a hierarchy of approximations concerned with (i) choice of a discrete basis set for electronic coordinates, (ii) semiclassical treatment of the nuclear motion, (iii) an appropriate model for the two-state electronic Hamiltonian, and (iv) a complete solution to that model.
Semiclassical Theory Of Inelastic Collisions Ii. Momentum Space Formulation, John B. Delos, Walter R. Thorson
Semiclassical Theory Of Inelastic Collisions Ii. Momentum Space Formulation, John B. Delos, Walter R. Thorson
Arts & Sciences Articles
The time-dependent equations of the classical picture of inelastic collisions (classical-trajectory equations) are derived using the momentum-space semiclassical approximation. Thereby it is shown that the classical-trajectory equations remain valid in the vicinity of classical turning points provided that (a) the momentum-space semiclassical approximation is valid, (b) the trajectories for elastic scattering in the various internal states differ only slightly, and (c) the slopes of the elastic scattering potentials have the same sign. A brief review of the existing derivations of the classical-trajectory equations is given, and the general conditions for their validity are discussed.
Completions Of Lattices With Semicomplementation, Alan A. Bishop
Completions Of Lattices With Semicomplementation, Alan A. Bishop
Dissertations
No abstract provided.
The Bi̇ngöl Earthquake Fault And Its Relation To The North Anatolian Fault Zone, İhsan Seymen, Atillâ Aydin
The Bi̇ngöl Earthquake Fault And Its Relation To The North Anatolian Fault Zone, İhsan Seymen, Atillâ Aydin
Bulletin of the Mineral Research and Exploration
No abstract provided.
Studies On Tunellite (Strontium Borate) Mineral, Hüseyin Gülensoy, T. Teberdar
Studies On Tunellite (Strontium Borate) Mineral, Hüseyin Gülensoy, T. Teberdar
Bulletin of the Mineral Research and Exploration
No abstract provided.
The Köprübaşi Ore Occurrence (Ne Turkey), Vojislav Vujanovi̇c
The Köprübaşi Ore Occurrence (Ne Turkey), Vojislav Vujanovi̇c
Bulletin of the Mineral Research and Exploration
No abstract provided.
Publications Of The Mineral Research And Exploration Institute Of Turkey, - -
Publications Of The Mineral Research And Exploration Institute Of Turkey, - -
Bulletin of the Mineral Research and Exploration
No abstract provided.