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2000

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Articles 2341 - 2370 of 2647

Full-Text Articles in Physical Sciences and Mathematics

Perkins County Test Hole Logs, Vincent H. Dreeszen Jan 2000

Perkins County Test Hole Logs, Vincent H. Dreeszen

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Rock County Test Hole Logs, Susan Olafsen Lackey, Frank A. Smith, Keonard R. Borcya Jan 2000

Rock County Test Hole Logs, Susan Olafsen Lackey, Frank A. Smith, Keonard R. Borcya

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Pierce County Test Hole Logs, Susan Olafsen Lackey, Frank A. Smith, Raymond R. Burchett Jan 2000

Pierce County Test Hole Logs, Susan Olafsen Lackey, Frank A. Smith, Raymond R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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York County Test Hole Logs, Frank A. Smith Jan 2000

York County Test Hole Logs, Frank A. Smith

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Resource Notes-Academic Year 1999-2000 Jan 2000

Resource Notes-Academic Year 1999-2000

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Resource News-Summer 2000 Jan 2000

Resource News-Summer 2000

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Principal Reservoirs In Nebraska, University Of Nebraska - Lincoln Jan 2000

Principal Reservoirs In Nebraska, University Of Nebraska - Lincoln

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Oregon Trail/Other Points Of Interest In Nebraska, University Of Nebraska - Lincoln Jan 2000

Oregon Trail/Other Points Of Interest In Nebraska, University Of Nebraska - Lincoln

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Excitation And Damping Of A Self-Modulated Laser Wakefield, Shouyuan Chen, M. Krishnan, Anatoly Maksimchuk, Donald P. Umstadter Jan 2000

Excitation And Damping Of A Self-Modulated Laser Wakefield, Shouyuan Chen, M. Krishnan, Anatoly Maksimchuk, Donald P. Umstadter

Donald Umstadter Publications

Spatially, temporally, and angularly resolved collinear collective Thomson scattering was used to diagnose the excitation and damping of a relativistic-phase-velocity self-modulated laser wakefield. The excitation of the electron plasma wave was observed to be driven by Raman-type instabilities. The damping is believed to originate from both electron beam loading and modulational instability. The collective Thomson scattering of a probe pulse from the ion acoustic waves, resulting from modulational instability, allows us to measure the temporal evolution of the plasma temperature. The latter was found to be consistent with the damping of the electron plasma wave.

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Nest Predation On Black-Tailed Prairie Dog Colonies, Bruce Baker, Thomas R. Stanley, Glenn Plumb Jan 2000

Nest Predation On Black-Tailed Prairie Dog Colonies, Bruce Baker, Thomas R. Stanley, Glenn Plumb

United States Geological Survey: Staff Publications

Nest predation is the principal cause of mortality for many grassland birds. Predation rates may be higher on prairie dog colonies because they may have less available nesting cover and may increase predator abundance. We compared 14-day nest predation rates for 1,764 artificial nests on 102 black-tailed prairie dog (Cynovnys ludovicianus) colonies and their paired off-colony sites (similar habitat lacking prairie dogs) from 14 May to 26 June 1998 in South Dakota and Wyoming. Predation rates on colonies (66.2 ± 2.2%; x ± SE) were 29.5% higher than at off-colony sites (51.1 ± 2.7%). Nesting cover on colonies …

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Cross Sections For Singly Differential And Total Ionization Of Helium By Electron Impact, Yong-Ki Kim, Walter R. Johnson, M. Eugene Rudd Jan 2000

Cross Sections For Singly Differential And Total Ionization Of Helium By Electron Impact, Yong-Ki Kim, Walter R. Johnson, M. Eugene Rudd

M. Eugene Rudd Publications

The binary-encounter dipole (BED) model for electron-impact ionization is applied to helium using the continuum dipole oscillator strength calculated from the relativistic random-phase approximation. The resulting total ionization cross section agrees with available experimental data well within the quoted experimental uncertainties. The singly differential (=energy distribution of ejected electrons) cross section agrees well in shape with available experiments. Because of the remarkable agreement with experiment at all incident and ejected electron energies and the compact analytic form of the cross sections, we propose that the BED cross sections for helium serve as a normalization standard with an accuracy of ±5% …

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Codes And Curves, Judy L. Walker Jan 2000

Codes And Curves, Judy L. Walker

Department of Mathematics: Faculty Publications

When information is transmitted, errors are likely to occur. Coding theory examines effi cient ways of packaging data so that these errors can be detected, or even corrected. The traditional tools of coding theory have come from combinatorics and group theory. Lately, however, coding theorists have added techniques from algebraic geometry to their toolboxes. In particular, by re-interpreting the Reed- Solomon codes, one can see how to defi ne new codes based on divisors on algebraic curves. For instance, using modular curves over fi nite fi elds, Tsfasman, Vladut, and Zink showed that one can defi ne a sequence of …

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Evaluation Of A Radar-Activated, Demand-Performance Bird Hazing System, Gwen R. Stevens, Jamie Rogue, Richard Weber, Larry Clark Jan 2000

Evaluation Of A Radar-Activated, Demand-Performance Bird Hazing System, Gwen R. Stevens, Jamie Rogue, Richard Weber, Larry Clark

United States Department of Agriculture Wildlife Services: Staff Publications

We evaluated a radar-activated integrated hazing system for the protection of waterfowl at large contaminated ponds at a power plant. The hazing devices in the system included acoustic alarm calls, pyrotechnics and chemical repellents dispersed in the form of a bird tear-gas. Unlike, timed interval systems, or systems with random activation sequences, birds did not habituate to the demand-performance system tested. Over the course of a year, we documented that waterfowl were 12.5 times less likely to fly over the hazed contaminated ponds relative to a non-hazed control pond. Of the waterfowl that did fly over both ponds, the likelihood …

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Natural And Anthropogenic Influences On The Distribution Of The Threatened Neosho Madtom In A Midwestern Warmwater Stream, Mark L. Wildhaber, Vernon M. Tabor, Daniel W. Mulhern, Kenneth L. Powell, Scott P. Sowa Jan 2000

Natural And Anthropogenic Influences On The Distribution Of The Threatened Neosho Madtom In A Midwestern Warmwater Stream, Mark L. Wildhaber, Vernon M. Tabor, Daniel W. Mulhern, Kenneth L. Powell, Scott P. Sowa

United States Geological Survey: Staff Publications

We attempted to discern the contributions of physical habitat, water chemistry, nutrients, and contaminants from historic lead-zinc mining activities on the riffle-dwelling benthic fish community of the Spring River, a mid western warm water stream that originates in Missouri and flows into Kansas and Oklahoma. The Spring River has a fish community that includes the Neosho madtom Noturus placidus, a species federally listed as threatened. Although anthropogenic factors such as contaminants limited populations and densities of fishes, an integrated assessment of natural and anthropogenic factors was necessary to effectively estimate the influence of the latter. Fish populations in the …

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Estuarine Relationships Between Zooplankton Community Structure And Trophic Gradients, Gyung Soo Park, Harold G. Marshall Jan 2000

Estuarine Relationships Between Zooplankton Community Structure And Trophic Gradients, Gyung Soo Park, Harold G. Marshall

Biological Sciences Faculty Publications

Zooplankton and water quality parameters were investigated at eight mesohaline stations in the lower Chesapeake Bay and Elizabeth River from January through December 1994 to identify the changes of zooplankton community structure with increased eutrophication. The total micro- and mesozooplankton biomass decreased with the increase of eutrophication. However, the relative proportion of microzooplankton increased with increased eutrophication. Within highly eutrophied waters, the small oligotrichs (m) and rotifers dominated the total zooplankton biomass (as carbon). However, tintinnids, copepod nauplii and mesozooplankton significantly decreased with the increase of eutrophication. These patterns were consistent throughout the seasons and had significant relationships statistically. These …

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B. A Java Dialectic, Douglas Lyon, Frances Grodzinsky Jan 2000

B. A Java Dialectic, Douglas Lyon, Frances Grodzinsky

School of Computer Science & Engineering Faculty Publications

Many books often gush over Java. People want to know, before they learn a language, what the drawbacks are for a language. They want to know what the strenghs are. After all, a computer language is just a tool. We shape our tools, and there after, our tools shape us! This chapter contains a dialog between three Java instructors. The participants are, Professors Good, Bad and Ugly. Professor Good is a strong proponent of Java. Professor Bad is a strong opponent of Java. Professor Ugly has been leaning toward the asthetic analysis of the language, particularly with an eye toward …

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Modeling The Bull Run River-Reservoir System, Scott A. Wells Jan 2000

Modeling The Bull Run River-Reservoir System, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The City of Portland, Water Bureau currently operates 2 Bull Run reservoirs, Reservoir #2 and Reservoir #1 as a water supply source in the Bull Run watershed shown in Figure 1 and Figure 2. The Water Bureau wants to operate their water supply system in order to meet both water supply objectives and fish habitat objectives downstream of the Bull Run reservoirs in Bull Run River. In addition, a third Bull Run reservoir has been proposed as an additional water supply source. This reservoir also may be used to meet water supply and fish habitat objectives in Bull Run River. …

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Determination Of Nizatidine-Guest Complexation Constants And Computer Aided Molecular Design, Carolyn J. Mordas Jan 2000

Determination Of Nizatidine-Guest Complexation Constants And Computer Aided Molecular Design, Carolyn J. Mordas

Honors Theses

Nizatidine, N-[2-[[[2-[(dimethylamino)methyl]-4-thiazoly]]methy1]thio]ethyl]-N'- methyl- 2-nitro-I,l, ethenediamine, has been investigated for its potential to act as a host to small molecules through hydrogen bonding and pi-pi interactions. In previous work, pyridoxine (vitamin B6) was hypothesized to have a high guest-host binding constant with nizatidine. This was supported through experimental methods involving one and two dimensional NMR spectroscopy, UV-visible spectroscopy, and high performance liquid chromatography. Computer aided molecular design and three dimensional conformationally flexible database searching led to the discovery of other possible guests, including albuterol, which has exhibited even higher binding constants from HPLC.

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สัมภาษณ์ : รองศาสตราจารย์ สุรี ขาวเธียร ประธานกรรมการประชาพิจารณ์ โครงการกำจัดมูลฝอยของกรุงเทพมหานคร, เสถียร รุจิรวนิช, ชัยรัตน์ วงศ์กิจรุ่งเรือง Jan 2000

สัมภาษณ์ : รองศาสตราจารย์ สุรี ขาวเธียร ประธานกรรมการประชาพิจารณ์ โครงการกำจัดมูลฝอยของกรุงเทพมหานคร, เสถียร รุจิรวนิช, ชัยรัตน์ วงศ์กิจรุ่งเรือง

Thai Environment

No abstract provided.

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สิ่งที่น่าสนใจบางประการของ "คำประกาศ" เกี่ยวกับวิทยาศาสตร์ จากการประชุมวิทยาศาสตร์ระดับโลก ปี 2542 (World Conference On Science), ทวีศักดิ์ ปิยะกาญจน์ Jan 2000

สิ่งที่น่าสนใจบางประการของ "คำประกาศ" เกี่ยวกับวิทยาศาสตร์ จากการประชุมวิทยาศาสตร์ระดับโลก ปี 2542 (World Conference On Science), ทวีศักดิ์ ปิยะกาญจน์

Thai Environment

No abstract provided.

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รัฐธรรมนูญกับการมีส่วนร่วมของประชาชนในการพิทักษ์สิ่งแวดล้อม, โกเมท ทองภิญโญชัย Jan 2000

รัฐธรรมนูญกับการมีส่วนร่วมของประชาชนในการพิทักษ์สิ่งแวดล้อม, โกเมท ทองภิญโญชัย

Thai Environment

No abstract provided.

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น้ำดื่มกับสุขภาพ : การเลือกเครื่องกรองนาประจำบ้าน, ธีรพล คังคะเกตุ Jan 2000

น้ำดื่มกับสุขภาพ : การเลือกเครื่องกรองนาประจำบ้าน, ธีรพล คังคะเกตุ

Thai Environment

No abstract provided.

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ร่างพระราชบัญญัติการจัดรูปที่ดินเพื่อพัฒนาเมือง, ชูขวัญ นิลศิริ Jan 2000

ร่างพระราชบัญญัติการจัดรูปที่ดินเพื่อพัฒนาเมือง, ชูขวัญ นิลศิริ

Thai Environment

No abstract provided.

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อันตรายจากไดออกซิน, ขนิษฐา ทวีถาวรสวัสดิ์ Jan 2000

อันตรายจากไดออกซิน, ขนิษฐา ทวีถาวรสวัสดิ์

Thai Environment

No abstract provided.

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Nitrogen Isotopic Composition Of Pore Water Ammonium, Blake Ridge, Site 997, Odp Leg 164, Walter S. Borowski, Charles K. Paull Jan 2000

Nitrogen Isotopic Composition Of Pore Water Ammonium, Blake Ridge, Site 997, Odp Leg 164, Walter S. Borowski, Charles K. Paull

EKU Faculty and Staff Scholarship

Ammonium (NH4 +) concentration profiles in piston-core sediments of the Carolina Rise and Blake Ridge generally have linear concentration profiles within the sulfate reduction zone (Borowski, 1998). Deep Sea Drilling Project (DSDP) Site 533, located on the Blake Ridge, also displayed a linear ammonium concentration profile through the sulfate reduction zone and the profile linearity continues into the upper methanogenic zone to a depth of ~200 meters below seafloor (mbsf), where the first methane gas hydrates probably occur (Jenden and Gieskes, 1983; Kvenvolden and Barnard, 1983). Sediments from the Ocean Drilling Program (ODP) Leg 164 deep holes (Sites 994, 995, …

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Significance Of Anaerobic Methane Oxidation In Methane-Rich Sediments Overlying The Blake Ridge Gas Hydrates, Walter S. Borowski, Tori M. Hoehler, Mark J. Alperin, Namcy M. Rodriguez, Charles K. Paull Jan 2000

Significance Of Anaerobic Methane Oxidation In Methane-Rich Sediments Overlying The Blake Ridge Gas Hydrates, Walter S. Borowski, Tori M. Hoehler, Mark J. Alperin, Namcy M. Rodriguez, Charles K. Paull

EKU Faculty and Staff Scholarship

A unique set of geochemical pore-water data, characterizing the sulfate reduction and uppermost methanogenic zones, has been collected at the Blake Ridge (offshore southeastern North America) from Ocean Drilling Program (ODP) Leg 164 cores and piston cores. The δ13 C values of dissolved CO2(Σ CO2) are as 13 C-depleted as –37.7‰ PDB (Site 995) at the sulfate-methane interface, reflecting a substantial contribution of isotopically light carbon from methane. Although the geochemical system is complex and difficult to fully quantify, we use two methods to constrain and illustrate the intensity of anaerobic methane oxidation in Blake Ridge sediments. An estimate using …

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Group Invariant Solutions Without Transversality, Ian M. Anderson, Mark E. Fels, Charles G. Torre Jan 2000

Group Invariant Solutions Without Transversality, Ian M. Anderson, Mark E. Fels, Charles G. Torre

All Physics Faculty Publications

We present a generalization of Lie's method for finding the group invariant solutions to a system of partial differential equations. Our generalization relaxes the standard transversality assumption and encompasses the common situation where the reduced differential equations for the group invariant solutions involve both fewer dependent and independent variables. The theoretical basis for our method is provided by a general existence theorem for the invariant sections, both local and global, of a bundle on which a finite dimensional Lie group acts. A simple and natural extension of our characterization of invariant sections leads to an intrinsic characterization of the reduced …

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Dolomitization And Dolomite Neomorphism: Trenton And Black River Limestones (Middle Ordovician) Northern Indiana, U.S.A., M. I N Chan, Jay M. Gregg, Kevin L. Shelton Jan 2000

Dolomitization And Dolomite Neomorphism: Trenton And Black River Limestones (Middle Ordovician) Northern Indiana, U.S.A., M. I N Chan, Jay M. Gregg, Kevin L. Shelton

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Trenton and Black River Limestones are dolomitized extensively along the axis of the Kankakee Arch in Indiana, with the proportion of dolomite decreasing to the south and southeast of the arch. Planar and nonplanar dolomite replacement textures and rhombic (type 1) and saddle (type 2) void-filling dolomite cements are present. Three stages of dolomitization, involving different fluids, are inferred on the basis of petrographic and geochemical characteristics of the dolomites. Nonferroan planar dolomite has relatively high δ18O values (-1.8 to -6.1‰ PDB) and has 87Sr/86Sr ratios (0.70833 to 0.70856) that overlap those of Middle Ordovician seawater. …

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Persistence Differences In Community College Courses Taught In Classrooms And Through Alternative Formats, Andrew A. Runyan Jan 2000

Persistence Differences In Community College Courses Taught In Classrooms And Through Alternative Formats, Andrew A. Runyan

CCAC Theses and Dissertations

While distance education programs continue to expand, the occurrence of higher dropout rates in those programs as compared to the same courses offered in lecture/lab settings remains a point of contention between supporters and detractors of non-traditional forms of education. This study used a foundation of research on dropout in higher education as the basis for an investigation of dropout rates in non-traditional forms of instruction in a community college setting. Course delivery formats studied included videotape-based courses, Internet-based courses, and courses offered in a self-paced laboratory environment. For each of these formats, the same course, offered in a lecture/lab …

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Geologic Map Of The Lima 30' X 60' Quadrangle, Southwest Montana, J. D. Lonn, B. Skipp, E. T. Ruppel, Susanne U. Janecke, W. J. Perry, J. W. Sears, M. J. Bartholomew, M. C. Stickney, W. J. Fritz, H. A. Hurlow, R. C. Thomas Jan 2000

Geologic Map Of The Lima 30' X 60' Quadrangle, Southwest Montana, J. D. Lonn, B. Skipp, E. T. Ruppel, Susanne U. Janecke, W. J. Perry, J. W. Sears, M. J. Bartholomew, M. C. Stickney, W. J. Fritz, H. A. Hurlow, R. C. Thomas

Geosciences Faculty Publications

No abstract provided.

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