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Articles 286201 - 286230 of 303795
Full-Text Articles in Physical Sciences and Mathematics
An Analysis Of Nitrate Concentrations In The Ground-Water Of Antwerp Township, Van Buren County, Michigan, John Emil Klanke
An Analysis Of Nitrate Concentrations In The Ground-Water Of Antwerp Township, Van Buren County, Michigan, John Emil Klanke
Masters Theses
Private wells were tested for nitrate during the spring of 1979 throughout sections of Antwerp Township, Van Buren County, southwestern Michigan (sections 1-5, 7-22, 24-26, 28-31, 33-36). Water samples were collected from 159 private wells and analyzed for nitrate. Nitrate concentrations ranged from less than 1 mg/1 NO3-N to 14.6 mg/1 NO3-N. Seven wells were found to have nitrate concentrations equaling or exceeding the National Interim Primary Drinking Water Standard of 10 mg/1 NO3-N. Nitrate concentrations were related to age of septic system, well depth below static water level, land use, and soil type. …
Precision Expansion Cloud Chamber For Homogeneous Nucleation Studies, John L. Schmitt
Precision Expansion Cloud Chamber For Homogeneous Nucleation Studies, John L. Schmitt
Physics Faculty Research & Creative Works
The author describes an expansion cloud chamber for the study of the nucleation of a single component vapor (homogeneous nucleation). The design draws on the many years of experience in this Center in construction of chambers for homogeneous nucleation of water. Design features of the chamber are exact control of temperature (±0.03° C), pressure (±0.5 mm Hg), and automatic control of cycling. Construction features are all construction materials are stainless steel, glass, or fluorocarbon plastics; the piston seal is a very flexible welded stainless-steel bellows; the chamber can be made very clean by heating under vacuum, and it is compatible …
Crystal Perfection Of Hgi2 Studied By Neutron And Gamma-Ray Diffraction, W. (William) B. Yelon, R. W. Alkire, M. M. Schieber, L. Van Den Berg, S. E. Rasmussen, H. Christensen, J. R. Schneider
Crystal Perfection Of Hgi2 Studied By Neutron And Gamma-Ray Diffraction, W. (William) B. Yelon, R. W. Alkire, M. M. Schieber, L. Van Den Berg, S. E. Rasmussen, H. Christensen, J. R. Schneider
Physics Faculty Research & Creative Works
The crystalline perfection of wire sawn pieces of vapor grown single crystals of mercuric iodide was compared with the perfection of (00l) cleaved sections of the same crystal from which nuclear radiation detectors have been fabricated. The crystalline perfection was studied using neutron and gamma-ray diffraction rocking curves. Most of the gamma-ray data were obtained using a high intensity source of 153Sm gamma rays with a wavelength of λ = 0.12 Å. Some of the data were obtained using highly penetrating 198Au gamma rays with a shorter wavelength of λ = 0.03 Å. The neutrons had a wavelength of λ …
Structural Analysis Of Precambrian Metasedimentary Rocks Of The Swede Gulch Formation, Nahant, South Dakota, Richard G. Cookman
Structural Analysis Of Precambrian Metasedimentary Rocks Of The Swede Gulch Formation, Nahant, South Dakota, Richard G. Cookman
Masters Theses
Precambrian X tectonites deformed between thermal domes in the northern Black Hills 1.7 B.Y.B.P. display variably trending isoclinal folds cross-cut by southeast trending slip-folds developed in discrete shear zones. Eugeosynclinal sedimentary rocks consisting of shale, quartzarenite , sublitharenite, and graywacke were metamorphosed to phyllite, quartzite, and metagraywacke during two syntectonic phases and one post-tectonic phase. The earliest syntectonic metamorphism was associated with development of isoclinal folds and may have produced amphibolite or greenschist facies. It was succeeded by retrograde metamorphism of greenschist facies syntectonic with and post-tectonic to development of southeast trending folds.
Mica, chlorite, iron oxides, and graphite are …
The Anodic Stripping Voltammetry Determination Of Trace Elements In Coal Ash, Jesus Montoya
The Anodic Stripping Voltammetry Determination Of Trace Elements In Coal Ash, Jesus Montoya
Masters Theses & Specialist Projects
The application of anodic stripping voltammetry (ASV) to the determination of several trace metals in coal ash was studied.
An ashing and ash digestion method was developed which limited the total salt and acid concentration of the analyte solutions, a necessary step for routine analysis. The simultaneous determination of cadmium, copper, lead, and zinc in eight Pennsylvania State University Coal Bank Samples and in the National Bureau of Standards SRM 1632a coal sample were made. Chromium was separated from the prepared coal ash solutions and determined independently in the form of chromate(VI).
All values determined by ASV methods were in …
Hydrology Of The Sinking Creek System, Logan And Simpson Counties, Kentucky, James C. Cubbage
Hydrology Of The Sinking Creek System, Logan And Simpson Counties, Kentucky, James C. Cubbage
Masters Theses & Specialist Projects
Southwest of Bowling Green, Kentucky, is the Western Pennyroyal, is a karstified area which has been neglected in the study of its ground water. About 100 square miles near Adairville were chosen for analysis to help rectify this lack of knowledge. The area is dominated by Sinking Creek, a surface-subsurface drainage system.
The main purpose of the study was to map the underground flow in the Sinking Creek area. The drainage system seemed to be typical for the Western Pennyroyal and exhibited many similarities to flow paths known in the Central Kentucky Karst.
The investigation proved to be of basic …
Radionuclides In Dardanelle Lake In The Area Of The Nuclear I Facility: 1979-1981, D. M. Chittenden Ii
Radionuclides In Dardanelle Lake In The Area Of The Nuclear I Facility: 1979-1981, D. M. Chittenden Ii
Arkansas Water Resources Center Technical Reports
The variations of the concentrations of 90Sr and 137Cs at four stations in Dardanelle Reservoir were analyzed as functions of two parameters: concentration of ionic species and the activity released, Ar, from the two 900 Mw reactors which use the reservoir as a source of cooling water. Multiple regression analyses were performed on the radionuclide concentrations using the two parameters as predictors. The analyses indicated that 90Sr is in a state of equilibrium between the solution and the suspended sediment. The position of the equilibrium was found to be quite sensitive to changes in the concentration of alkaline earth cations, …
A Salt And Water Balance Model For A Silt Loam Soil Cropped To Rice And Soybean, J. T. Gilmour, J. A. Ferguson, B. R. Wells
A Salt And Water Balance Model For A Silt Loam Soil Cropped To Rice And Soybean, J. T. Gilmour, J. A. Ferguson, B. R. Wells
Arkansas Water Resources Center Technical Reports
A computer model was developed which described salt and water balances for a silt loam soil common to the Grand Praire physiographic region of Arkansas. A ten year period of weather data (1966-75) was used as input data for two divergent cases in regard to salt accumulation. Case one was a rice-soybean rotation with soybean irrigated, while case two was a rice-soybean-soybean rotation with soybean not irrigated. Salts considered were calcium, magnesium, sodium, sulfate and chloride as well as the precipitate, calcium carbonate. Where soybeans were not irrigated less evapotranspiration, more infiltration and less runoff were observed during the fallow …
Suitability Of Egyptian Raw Materials For The Production Of Cement Clinker Using The Dry Process, Lamia Rifaat Ismail
Suitability Of Egyptian Raw Materials For The Production Of Cement Clinker Using The Dry Process, Lamia Rifaat Ismail
Archived Theses and Dissertations
No abstract provided.
Scs 61: The Category Cd Of Completely Distributive Lattices And Their Free Objects, Karl Heinrich Hofmann
Scs 61: The Category Cd Of Completely Distributive Lattices And Their Free Objects, Karl Heinrich Hofmann
Seminar on Continuity in Semilattices
No abstract provided.
Scs 60: Miniworkshop On Continuous Lattices At Tulane University From Thursday, November 19, 1981 Through Saturday, November 21, 1981, Karl Heinrich Hofmann
Scs 60: Miniworkshop On Continuous Lattices At Tulane University From Thursday, November 19, 1981 Through Saturday, November 21, 1981, Karl Heinrich Hofmann
Seminar on Continuity in Semilattices
No abstract provided.
The Determination Of A Relative Chronology For A Surface Archeological Site Using The Obsidian Hydration Dating Method, Scott Preston Thomas
The Determination Of A Relative Chronology For A Surface Archeological Site Using The Obsidian Hydration Dating Method, Scott Preston Thomas
Dissertations and Theses
This methodological study is an attempt to develop relative chronologies for surface archaeological sites from the obsidian hydration analysis of waste flake samples. Two sites in southeastern Oregon were selected and their surface components sampled. The results of the obsidian hydration analysis indicate, that with the use of random sampling methods and general geochemical control, a fairly accurate representation of the history of an archaeological surface site can be obtained.
Scs 59: Sober Quotients, John R. Isbell
Scs 59: Sober Quotients, John R. Isbell
Seminar on Continuity in Semilattices
No abstract provided.
Mid‐Level Intrusions At The Continental Shelf Edge, Christopher S. Welch
Mid‐Level Intrusions At The Continental Shelf Edge, Christopher S. Welch
VIMS Articles
Observations across the continental shelf offshore from New Jersey in late summer 1976 show an intrusion of saline water at the mid level of the water column across the shelf edge front, which appears in density only as an offshore thickening of the pycnocline. This internal density field produces horizontal pressure gradient forces within the pycnocline in the onshore direction. These forces, in the linearized equation of motion with a constant eddy viscosity, drive a circulation which resembles a double Ekman spiral for internal pressure vertical distributions which are thin with respect to the Ekman depth. For thick pressure distributions, …
Chemistry Of Chromium Oxyfluorides And Group Vib Perfluoroglutarates, Bruce Michael Johnson
Chemistry Of Chromium Oxyfluorides And Group Vib Perfluoroglutarates, Bruce Michael Johnson
Dissertations and Theses
Pure chromium oxide trifluoride was prepared for the first time by reaction of CrO₃ and ClF with subsequent multiple fluorine treatments at 120°C. On the basis of its infrared spectrum, the purple CrOF₃ was assigned as a fluorine-bridged polymer with terminal oxygen groups. Chromium oxide trifluoride was found to be stable to 300°C, where it decomposes with the loss of oxygen to CrF₃.
Bilinear Equation For The Cylinder With Overlap And The Pomeron Residue, Paul Finkler, C. Edward Jones
Bilinear Equation For The Cylinder With Overlap And The Pomeron Residue, Paul Finkler, C. Edward Jones
Paul Finkler Papers
A bilinear integral equation for the cylinder is derived within the meson sector of the theory of dual topological unitarization. The equation is more general than conventional linear cylinder equations since it includes regions of phase space in which produced particles overlap in rapidity. The equation also permits a simple treatment of phase space which corresponds to that of the planar bootstrap problem. Two classes of solutions are found, only one of which results in the Pomero'n-f identity. This treatment also indicates that the residue of the Pomeron may be twice as large as that suggested by earlier calculations …
Some Results On Optimum Premium Payment Plans, Jeyaraj Vadiveloo, Kishan Mehrotra, Kenneth Kaminsky
Some Results On Optimum Premium Payment Plans, Jeyaraj Vadiveloo, Kishan Mehrotra, Kenneth Kaminsky
Electrical Engineering and Computer Science - Technical Reports
Any insurance plan consists of a sequence of payments every year (or some other fixed time interval) in return for certain death benefits. The benefits may take the form of a wide variety of insurances or annuities. For simplicity, we will assume that premiums and benefits are paid annually. In this paper, we investigate the appropriateness of this type of plan. Naturally, appropriateness of any plan cannot be measured without an optimality criteria. Three such criteria, which are statistical in nature, are introduced in this paper. For the principal "safety" criterion which we use, the optimal premium are those which …
Water Current, Volume 13, No. 6, November/December 1981
Water Current, Volume 13, No. 6, November/December 1981
Water Current Newsletter
Water Seminars Start in January
UNL Coordinates Three University Study of 1976-77 Drought Relief Program
1980 River Basin Proceedings Published
Water Planning Update
NWRC Staffer Now Fellow at UNL Great Plains Center
Research Review: Distribution of Nitrogen Under Native Range Cultivated Fields in the Nebraska Sandhills
Nebraska Could Add Muscle to Interstate Water Negotiations
Laws Prevent Use of Permit System in Nebraska's Sandhills
Fischbach Predicts Irrigation Scheduling Will Catch On
Comments Wanted on Newsletter Format
Additive Comparisons Of Stop Rule And Supremum Expectations Of Uniformly Bounded Independent Random Variables, Theodore P. Hill, Robert P. Kertz
Additive Comparisons Of Stop Rule And Supremum Expectations Of Uniformly Bounded Independent Random Variables, Theodore P. Hill, Robert P. Kertz
Research Scholars in Residence
Let XI, X2, . . . be independent random variables taking values in [a, b], and let T denote the stop rules for X1, X2, Then E(supn>1 Xn) - sup{ EXt t ≡ T} < (1/4)(b - a), and this bound is best possible. Probabilistically, this says that if a prophet (player with complete foresight) makes a side payment of (b - a)/8 to a gambler (player using nonanticipating stop rules), the game becomes at least fair for the gambler.
Use Of Magnesium (Mg) For Crop Production In Kentucky, John H. Grove
Use Of Magnesium (Mg) For Crop Production In Kentucky, John H. Grove
Soil Science News and Views
Magnesium (Mg) is an important element in the nutrition of plants and animals, although it has long been considered a "secondary" nutrient for plants. Nitrogen (N), phosphorus (P), and potassium (K) are "primary'' nutrients and are usually given the greatest consideration in crop fertility programs. However, as yield levels have risen, more attention has been directed towards Mg and other nutrient elements. Concern about hypomagnesemia (grass tetany) in ruminants (cattle, sheep) has led to particular concern about soil and plant Mg levels.
Volume 5, Number 11 (November 1981), The Solar Ocean Energy Liaison
Volume 5, Number 11 (November 1981), The Solar Ocean Energy Liaison
The OTEC Liaison
No abstract provided.
Monthly Planet, 1981, November, Jim Springer, Huxley College Of The Environment, Western Washington University
Monthly Planet, 1981, November, Jim Springer, Huxley College Of The Environment, Western Washington University
The Planet
No abstract provided.
Miiiikan Award For 1981, Robert Fuller
Miiiikan Award For 1981, Robert Fuller
Robert G. Fuller Publications
In conclusion, for his notable and creative contributions to physics teaching, in particular how he has alerted us to the implications of our cultural assumptions, how he has found interesting physics everywhere, and how he has valued the humanity of physics, the American Association of Physics Teachers presents to Albert A. Bartlett the 1981 Robert A. Millikan Award.
Magnetic And Electrical Properties Of Iron-Nickel-Chromium-Metalloid Glasses, H. Sadate-Akhavi, George C. Hadjipanayis, David J. Sellmyer
Magnetic And Electrical Properties Of Iron-Nickel-Chromium-Metalloid Glasses, H. Sadate-Akhavi, George C. Hadjipanayis, David J. Sellmyer
David Sellmyer Publications
The magnetic and electrical properties of amorphous (Fe1-xNix)78-yCrySi10B12 alloys have been measured between 4.2 and 300 K. Alloys with x≤0.9 and y=5 order ferromagnetically. High-field magnetization measurements show saturation in moderate fields suggesting a relatively high value of magnetic anisotropy which was estimated to be K≃106 erg/cm3. The magnetization at low temperatures follows a T3/2 law leading to a spin-wave stiffness coefficient D≃90 meV Å2. The x=1, y=5 alloy behaves like a "cluster glass" with a cluster ordering temperature around 20 …
The Probe, Issue 17 - November 1981
The Probe, Issue 17 - November 1981
The Probe: Newsletter of the National Animal Damage Control Association
THE PROBE National Animal Damage Control Association November, 1981
It is now time to pay your dues.
Bats roosting in an attic can provide a free and easy way to keep a house warm in winter.
THE NO ANTIDOTE 1080
ORCHARD MOUSE CONTROL
The highly publicized "Adopt-a-Horse" program of the FRIENDS UF ANIMALS that was foisted on the Bureau of Land Management (BLM) is undergoing reevaluation.
NADCA ANNUAL MEETING
ASTM SYMPOSIUM ANNOUNCEMENT
WILDLIFE MANAGEMENT ON PUBLIC LANDS
Cats won't chase birds at the bird feeder if you feed the birds lemon-scented bird seed.
The killing of the three-year old by …
Statistics Of Multicharge Centers In Semiconductors - Applications, David C. Look
Statistics Of Multicharge Centers In Semiconductors - Applications, David C. Look
Physics Faculty Publications
A general formula is derived for the electron occupation numbers appropriate for multicharge centers in semiconductors, including excited states. The results are used to rederive and generalize several formulas of interest in the literature, in order to show exactly how the degeneracies of individual states enter in. Particular attention is paid to certain subjects which are sometimes confusing, such as how the statistics of band states differ from those those of localized states. Another subject of much recent interest, negative-U centers, is dealt with in some detail. We show how the dependence of the average occupation number on Fermi …
Massive Neutrinos And The Stellar Stopping Power Via The Neutrino Magnetic Moment, P.T. Leung, M. L. Rustgi, J. E. Turner, Werner Brandt
Massive Neutrinos And The Stellar Stopping Power Via The Neutrino Magnetic Moment, P.T. Leung, M. L. Rustgi, J. E. Turner, Werner Brandt
Physics Faculty Publications and Presentations
An exact expression is derived within the high-Q approximation for the spectrum of energy losses of neutrinos interacting via their magnetic moment with electrons. A formula for the stopping power of matter for neutrinos is derived and applied to the study of the solar neutrino anomaly. The total inelastic cross section is given. An upper limit is deduced for the neutrino magnetic moment from the antineutrino spectrum as recently parameterized by Lee (1979). It confirms the bound reported by Cowan and Reines. The distance for stellar neutrinos to thermalize by the interactions studied here, through encounters with stars is found …
Gravity And Ground Magnetic Investigations In Eastern Nebraska, Robert F. Diffendal Jr., R. R. Burchett
Gravity And Ground Magnetic Investigations In Eastern Nebraska, Robert F. Diffendal Jr., R. R. Burchett
Robert F. Diffendal, Jr., Publications
The purpose of this investigation was to extend the area covered by gravity and ground magnetic data related to the Nemaha Uplift and associated structures in eastern Nebraska. Gravity data were collected from Clay, Fillmore, Hamilton, Nuckolls, Polk, Thayer, and York Counties. Additional ground magnetic data and gravity data were collected for central Otoe County.
John Muir Newsletter, November 1981, Holt-Atherton Pacific Center For Western Studies
John Muir Newsletter, November 1981, Holt-Atherton Pacific Center For Western Studies
Muir Center Newsletters (1981-2015)
Holt-Atherton Pacific Center for Western Studies *_~fc~_j«t-fc University of the Pacific Stockton, Calif 95211 VOLUME 1 .NOVEMBER 1981 NUMBER 5 EDITORIAL STAFF: RONALD H. LIMBAUGH. JANICE D. MAGDICH URGENT URGENT- .—-URGENT ■ URGENT 'We have just received word from the Coalition to Save our Documentary Heritage that Congress will act within the next few days on an appropriations bill(H.R. Ul2l) for the National Archives which includes an earmarked amount of "up to" three million dollars for the National Historical Publications and Records Commission, the funding agency for the John Muir Microform Project. Since each side has proposed separate legislation, a …
Existence Of Periodic Solutions Of Nonlinear Boundary Value Problems And The Method Of Upper And Lower Solutions, V. Lakshmikantham, R. Kannan
Existence Of Periodic Solutions Of Nonlinear Boundary Value Problems And The Method Of Upper And Lower Solutions, V. Lakshmikantham, R. Kannan
Mathematics Technical Papers
We study the existence of periodic solutions of second order nonlinear differential equations by combining the method of upper and lower solutions and the method of Alternative problems. Besides including previous results of other authors, we obtain criteria which are easily verifiable. These criteria are in a form that they can be adapted for partial differential equations of parabolic and elliptic type.