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Beryllium-7 And Lead-210 In The Atmosphere And Surface Snow Over The Greenland Ice Sheet In The Summer Of 1989, Jack E. Dibb Dec 1990

Beryllium-7 And Lead-210 In The Atmosphere And Surface Snow Over The Greenland Ice Sheet In The Summer Of 1989, Jack E. Dibb

Earth Sciences

The concentrations of 7Be and 210Pb were measured in surface air and fresh and aging snow samples from Summit (72°20′N, 38°45′W) and Dye 3 (65°10′N, 44°45′W) Greenland, during June and July 1989. The aerosol concentrations of these radionuclides showed rapid variations at both sites, but were nearly twice as high, on average, at Summit. Concentrations in the 16 fresh snowfall events that were sampled also showed wide variability, but the averages were the same at the two sites. The apparent difference in air-snow fractionation and the lack of coherence in the concentration in air time series between the …


John Muir Newsletter, Winter 1990/1991, John Muir Center For Regional Studies Dec 1990

John Muir Newsletter, Winter 1990/1991, John Muir Center For Regional Studies

Muir Center Newsletters (1981-2015)

John Muir Newsletter winter, 1990-1991 JOHN MUIR NEWSLETTER REVIVED The John Muir Center for Regional Studies at the University of thePacific is very pleased to begin republication of the John Muir Newsletter. The first newsletter under this title ran six years and ended with the publication of the John Muir Papers (microform edition) in 1986. The current quarterly Newsletter will be published in fall and spring of each year, starting with this fall 1990 issue. The Newsletter will serve as a clearing house of information on John Muir, publications and events concerning Muir and his legacy, news of the environment, …


Intracellular Degradation Of Ribosomes In A Mesophilic And A Thermophilic Species Of Bacillus, Joe William Davis Dec 1990

Intracellular Degradation Of Ribosomes In A Mesophilic And A Thermophilic Species Of Bacillus, Joe William Davis

Dissertations

The rates of intracellular degradation of ribosomal proteins were compared in a mesophilic and a thermophilic species of Bacillus. Cells were grown under various incubation conditions in the presence of a 14^C-protein hydrolysate m order to label the ribosomes. Rates of ribosome degradation were evaluated in terms of changes in the specific activity of in vivo ribosomes as a function of incubation time. The results indicated that, under most conditions, ribosomes were degraded (in vivo) at similar rates in both the mesophile and the thermophile. In some studies, ribosome degradation rates were slightly faster for the thermophile than for the …


A Compact Optical Associative Memory Using Dynamic Holographic Storage Media And Photorefractive Gain And Attenuation Elements, Thomas J. Burns Dec 1990

A Compact Optical Associative Memory Using Dynamic Holographic Storage Media And Photorefractive Gain And Attenuation Elements, Thomas J. Burns

Theses and Dissertations

This research effort implemented a compact optical associative memory architecture consisting of a Fabry-Perot Confocal Resonator (FPCR) optical processing environment, two dynamically reprogrammable Lithium Niobate volume holograms, and Barium Titanate gain and attenuation elements. The reduced physical dimensions of the compact optical processing environment make it more adaptable to military applications than previous associative memory designs. The FPCR employs Mangin mirrors designed to reduce spherical aberrations in off-axis rays. The orientation of the gain element's grating vector angle and the model used to predict the profile of the attenuation element were unique to this research effort. The object stored in …


Using Error Detection And Correction Coding For A Turbulent Atmospheric Optical Communications Link, Mark A. Cloutier Dec 1990

Using Error Detection And Correction Coding For A Turbulent Atmospheric Optical Communications Link, Mark A. Cloutier

Theses and Dissertations

Probability of bit error (Pb) performance for a turbulent, atmospheric, optical, communications link with convolutional error detection and correction coding was investigated. The codes investigated were all rate 1/2 codes with constraint lengths ranging from 3 to 7. It was assumed that the coded data stream was sufficiently interleaved so that the turbulent channel could be considered memoryless. A theoretical bound on Pb, given by Viterbi for a memoryless channel, was used to plot curves of Pb versus the signal intensity of last transmitter. These curves were plotted for three different levels of atmospheric turbulence and three …


An Optically Pumped Molecular Bromine Laser, Jon W. Morrison Dec 1990

An Optically Pumped Molecular Bromine Laser, Jon W. Morrison

Theses and Dissertations

An optically pumped molecular bromine laser was studied to investigate the quenching kinetics state of Br2. This included characterization of the pressure dependence of the laser output power. The approach was to excite molecular bromine in a sealed cell with a Nd:YAG pumped dye laser. Unresolved side fluorescence and amplified stimulated emission (ASE) spectra were recorded. ASE offered the advantage of a simpler optical system with no externally induced wavelength dependencies. Stimulated emission as a signal monitor offered greater resolution than side fluorescence spectra and facilitated spectroscopic assignment.


Determination Of The Optical Properties Of Organic Thin Films By Spectroscopic Ellipsometry, Mark L. Sward Dec 1990

Determination Of The Optical Properties Of Organic Thin Films By Spectroscopic Ellipsometry, Mark L. Sward

Theses and Dissertations

This thesis demonstrated the feasibility of determining the optical properties of organic and polymer thin films through the use of Spectroscopic Ellipsometry (SE). Tan Psi and cos Delta data from 300-800 nanometers (NM) were taken with a Rudolph Research s2000 spectroscopic ellipsometer four samples: indium tin oxide (ITO) coated glass; five layer poly-benzyl-L glutamate (PBLG) organic film on ITO coated glass; eight layer PBLG film on ITO coated glass; and a thiophene polymer film on a microscope slide. The data sets were fit to a choice of four computer models based on a paper written by Dwight Berreman in 1972. …


Characterization Of Barium Titanate As An Optical Amplifier, George A. Vogel Dec 1990

Characterization Of Barium Titanate As An Optical Amplifier, George A. Vogel

Theses and Dissertations

The introduction of two-beam coupling in photorefractive materials has resulted in an extensive amount of research into their use as optical processing/computing elements. This dissertation develops the theoretical equations for two-beam coupling in barium titanate as an optical amplifier. One of the factors which limits the optical gain in photorefractive crystals is the loss of pump beam power to the amplification of parasitic light (beam fanning). This parasitic light is produced by light scattered from the pump beam by imperfections on both the crystal face and within the crystal. Through the analysis of signal and noise amplification as functions of …


United States Patent: Metaginsulator Composites Having Improved Properties And Method For Their Preparation, Chia-Ling Chien, Gang Xiao, Sy-Hwang Liou Nov 1990

United States Patent: Metaginsulator Composites Having Improved Properties And Method For Their Preparation, Chia-Ling Chien, Gang Xiao, Sy-Hwang Liou

Sy-Hwang Liou Publications

Improved cermets having superior properties comprising a ferromagnetic metal and an insulator. By controlling process conditions, cermets having high magnetization and high coercivity as well as chemical stability, wear resistance and corrosion resistance are prepared. The cermets of this invention find particular utility as high density recording media.


Management Of Interdependent Data: Specifying Dependency And Consistency Requirements, Amit P. Sheth, Marek Rusinkiewicz Nov 1990

Management Of Interdependent Data: Specifying Dependency And Consistency Requirements, Amit P. Sheth, Marek Rusinkiewicz

Kno.e.sis Publications

Multiple databases that serve the needs of various application systems are considered. One of the significant problems in managing these databases is to maintain the related data items consistent to the required degree. This problem is frequently referred to as `redundant data management'. Since the term `redundancy' tends to imply that the data is unwanted or superfluous, the authors use the more general term `management of interdependent data'. Some preliminary ideas in this area are discussed. The problem of managing interdependent data is characterized, and some important types of interdatabase dependency are identified.


Part I: Oxidation Of Heavy Metal Sulfides In Relation To The Environment; Part Ii: Fundamental Theory & Experiments Concerning Gas Chromatography & Mass Spectrometry, Judith Morgan Nov 1990

Part I: Oxidation Of Heavy Metal Sulfides In Relation To The Environment; Part Ii: Fundamental Theory & Experiments Concerning Gas Chromatography & Mass Spectrometry, Judith Morgan

Masters Theses & Specialist Projects

Oxidation of heavy metal sulfides is a thermodynamically spontaneous process. Because of this, metal sulfides in the presence of oxygen are not stable. Currently there are over 100 streams and rivers, within the U.S., contaminated with heavy metal mine drainage; therefore an approved method of restoration is necessary. Precipitation of heavy metals as sulfides using H2S as a reductant has been favorably reviewed as a restorative technique to clean up mining areas. However, using this technique on the laboratory scale does not prove to be a viable answer and shows strong pH dependence.

In the past three years …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, November 1990, College Of Engineering And Computer Science, Wright State University Nov 1990

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, November 1990, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


Water Resources Review - November 1990 Vol 3 No 3, Annis Water Resources Institute Nov 1990

Water Resources Review - November 1990 Vol 3 No 3, Annis Water Resources Institute

AWRI Reviews

No abstract provided.


Fiber Distributed Data Interface, Piyush Kulshreshiha Oct 1990

Fiber Distributed Data Interface, Piyush Kulshreshiha

Department of Computer Science Technical Reports

No abstract provided.


1990scholars And Artists Bibliography, Michael Schwartz Library, Cleveland State University, Friends Of The Michael Schwartz Library Oct 1990

1990scholars And Artists Bibliography, Michael Schwartz Library, Cleveland State University, Friends Of The Michael Schwartz Library

Scholars and Artists Bibliographies

This bibliography was created for the annual Friends of the Michael Schwartz Library Scholars and Artists Reception, recognizing scholarly and creative achievements of Cleveland State University faculty, staff and emeriti


Ua77/1 Alumni, Wku Alumni Relations Oct 1990

Ua77/1 Alumni, Wku Alumni Relations

WKU Administration Documents

WKU's alumni magazine. Contents:

  • Dancing on Walls - Governor's Scholars Program
  • An Anniversary Gift - Preston Health & Activities Center
  • 1990 Alumni Annual Student Phonathon
  • A Sturdy Individualist - Virginia Woods
  • Turn Your Radio On - WKYU-FM
  • Competitive Edge - Miss Kentucky, Miss Western
  • Excitement! - 1990 Homecoming
  • Mammoth Cave is a Cool Spot in a Hot Summer


Student Fact Book, Fall 1990, Wright State University, Office Of Student Information Systems, Wright State University Oct 1990

Student Fact Book, Fall 1990, Wright State University, Office Of Student Information Systems, Wright State University

Wright State University Student Fact Books

The student fact book has general demographic information on all students enrolled at Wright State University for Fall Quarter, 1990.


Mossbauer Spectroscopy Of Fe2+ Binding To Apo And Holo Mammalian Ferritin, Richard B. Frankel, Gerald D. Watt, Georgia C. Papaefthymiou Oct 1990

Mossbauer Spectroscopy Of Fe2+ Binding To Apo And Holo Mammalian Ferritin, Richard B. Frankel, Gerald D. Watt, Georgia C. Papaefthymiou

Physics

The anaerobic binding of Fe2+ to apo and holo Mammalian ferritin has been studied in the pH range from 6.0 to 10.0. Mossbauer spectroscopy of samples in which the added Fe 2+ is enriched in Fe-57 shows that the Fe2+ ions bind to the ferritin core and exchange electrons with Fe3+ ions in the core.


The Effects Of Two Polycyclic Aromatic Hydrocarbons Benzo[A]Pyrene And Naphthalene On Reproductive Success Embryological Development Larval Physiology And Mortality Of The Mud Crab Rhithropanopeus Harisii (Gould), Gregory V. White Oct 1990

The Effects Of Two Polycyclic Aromatic Hydrocarbons Benzo[A]Pyrene And Naphthalene On Reproductive Success Embryological Development Larval Physiology And Mortality Of The Mud Crab Rhithropanopeus Harisii (Gould), Gregory V. White

OES Theses and Dissertations

Polycyclic aromatic hydrocarbons (PAHs) such as naphthalene (Nap) and benzo[a]pyrene (B[a]P) are common in the water column and sediments of estuarine and coastal areas. The mud crab Rhithropanopeus harrisii was exposed to varying concentrations of Nap or B[a]P to determine the effects on reproductive success, embryological development, larval physiology and mortality. Nap and B[a]P decreased hatching success and prolonged embryological development. Both pollutants produced high abnormality frequencies for egg exposed larvae. Molt frequency and respiratory rates of larvae from non-exposed eggs were more chronically affected by these pollutants than were egg exposed larvae. The EC50 concentrations were determined for …


Hawaii's Hottest Issue: Update On Geothermal Development, Paul Faulstich Sep 1990

Hawaii's Hottest Issue: Update On Geothermal Development, Paul Faulstich

Pitzer Faculty Publications and Research

Walking through Hawai'i's Wao Kele O Puna rainforest, you can hear the coarse volcanic soil crunch underfoot. A surrealistic calm lingers in the thick air while songbirds call out from the understory. Yet this is a forest under siege.

Geothermal developers want to tap the volcanic heat beneath the Wao Kele O Puna forest and use it to make electricity and profits.


Malaysian Deforestation Proceeds Apace, Paul Faulstich Sep 1990

Malaysian Deforestation Proceeds Apace, Paul Faulstich

Pitzer Faculty Publications and Research

A hunger fast, dubbed Fast Action, was staged in front of the Japanese Consulate General in Honolulu on July 20 to protest the destruction of the most ancient and biologically diverse ecosystem on Earth. Organized by Hawai'i Earth First! and the O'ahu Rainforest Action Group, Fast Action was designed to alert people to the destruction of tropical rainforests in Sarawak, Malaysia. Protesters demanded on immediate moratorium on the cutting of rainforests in,which the Penan and other-native peoples live.


The Probe, Issue 104 - September/October 1990 Sep 1990

The Probe, Issue 104 - September/October 1990

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE National Animal Damage Control Association
SEPTEMBER/OCTOBER 1990
Pride and Professionalism In ADC
Hawthorne Wraps Up ADC Four Corners Rendezvous
Prevention and Control Tips
White-footed and Deer Mice
Pesticide Updates
Wildlife Damage in the News
Animal Damage Control


Superfund Record Of Decision: Monticello Mill Tailings (Doe), Ut First Remedial Action, U.S. Environmental Protection Agency, Office Of Emergency And Remedial Response Aug 1990

Superfund Record Of Decision: Monticello Mill Tailings (Doe), Ut First Remedial Action, U.S. Environmental Protection Agency, Office Of Emergency And Remedial Response

All U.S. Government Documents (Utah Regional Depository)

The 300-acre Monticello Mill Tailings site is comprised of a 7S-acre inactive uranium and vanadium milling operation and affected peripheral properties in Monticello, San Juan County, Utah. Surrounding land use is rural residential and agricultural. The site overlies a shallow alluvial aquifer, and part of the site lies within the floodplain of Montezuma Creek. Approximately IS-acres of wetlands adjacent to Montezuma Creek also have been contaminated by tailings. In 1940, the site was operated as a vanadium ore-buying station. Milling of ore began in 1942, and a vanadium/uranium sludge product was produced onsite from 1943 to 1944. Onsite uranium milling …


Monte Carlo Simulation Of Atmospheric Neutron Transport At High Altitudes Using Mcnp, Donald R. Culp, David L. Monti, James R. Shoemaker, David Wesley, Kirk A. Mathews Aug 1990

Monte Carlo Simulation Of Atmospheric Neutron Transport At High Altitudes Using Mcnp, Donald R. Culp, David L. Monti, James R. Shoemaker, David Wesley, Kirk A. Mathews

AFIT Documents

Neutron transport calculations were performed using the Monte Carol code, MCNP. The transport problem considered has a point source at high altitude (40 km). Since atmospheric density decreases with altitude, two-dimensional effects (cylindrical coordinates) can be important. Results were compared to those obtained with the SMAUG-II computer code, which performs mass-integral scaling of approximate fits to one-dimensional spherical discrete ordinates solutions. These comparisons show the importance of two-dimensional computations. The report discusses practical issues of applying MCNP to this problem, without code modifications and includes example input files for MCNP and for SMAUG-II. Computational modelling of neutron transport in the …


Modeling Mass Transport In Aquifers: The Distributed Source Problem, Sergio E. Serrano Aug 1990

Modeling Mass Transport In Aquifers: The Distributed Source Problem, Sergio E. Serrano

KWRRI Research Reports

This report presents a new methodology to model the time and space evolution of groundwater variables in a system of aquifers when certain components of the model, such as the geohydrologic information, the boundary conditions, the magnitude and variability of the sources or physical parameters are uncertain and defined in stochastic terms. This facilitates a more realistic statistical representation of groundwater flow and groundwater pollution forecasting for either the saturated or the unsaturated zone. The method is based on applications of modern mathematics to the solution of the resulting stochastic transport equations. This procedure exhibits considerable advantages over the existing …


Effects Of Aromatic Concentration On Methane Fermentation, Yi-Tin Wang, Pin-Chieh Pai, H. David Gabbard Aug 1990

Effects Of Aromatic Concentration On Methane Fermentation, Yi-Tin Wang, Pin-Chieh Pai, H. David Gabbard

KWRRI Research Reports

The anaerobic biodegradability and toxicity of fourteen aromatic compounds were evaluated over a wide range of concentrations using a serum bottle technique. Benzene, toluene, and all three isomers of xylene were not significantly degraded to methane in a phenol-enriched culture. Complete degradation of 1000 mg/L phenol, 800 mg/L catechol, 100 mg/L 2-NP, 100 mg/L 3- NP, and 100 mg/L 4-NP was observed within two months while depletion of 100 mg/L resorcinol and 1000 mg/L hydroquinone required more than six and eight months incubation, respectively. None of the three isomers of chlorophenol were degraded in the phenol-enriched culture. Batch toxicity assay …


A Simulation Of A Multi-Hop Communications Network Using A Kinematic Topology Generator And Static Sphere-Packing Power Control, Kevin Charles Davis Aug 1990

A Simulation Of A Multi-Hop Communications Network Using A Kinematic Topology Generator And Static Sphere-Packing Power Control, Kevin Charles Davis

Masters Theses

No abstract provided.


Water Resources Review - August 1990 Vol 3 No 2, Annis Water Resources Institute Aug 1990

Water Resources Review - August 1990 Vol 3 No 2, Annis Water Resources Institute

AWRI Reviews

No abstract provided.


The Gamut: A Journal Of Ideas And Information, No. 30, Summer 1990, Cleveland State University Jul 1990

The Gamut: A Journal Of Ideas And Information, No. 30, Summer 1990, Cleveland State University

The Gamut Archives

CONTENTS OF ISSUE NO. 30, SUMMER, 1990

Louis T. Milic: A Fire in the Kitchen, 2

Leonard M. Trawick: A Place in the Ecosystem, 3

Tenth Anniversary Contest Winners

Jill Wilson Brennan: Terrorism Against Americans, 5

Daniel Hill: The Battle Over Native American Remains, 16

Science, piety, and politics

Todd Lieber: "How Many Acres You Got Out There?", 24

Independent farmers in the age of agribusiness

Eric May: Wood Engravings, 30

Jacque Parsley: Collage/ Assemblage, 35

P.J. Rogers: Aquatint/ Etchings, 40

Richard Kraus: On Vacation, 47

Dashka Slater: Persephone Tells, …


Santa Clara Magazine, Volume 32 Number 4, Summer 1990, Santa Clara University Jul 1990

Santa Clara Magazine, Volume 32 Number 4, Summer 1990, Santa Clara University

Santa Clara Magazine

10 - WHAT'S UP WITH COMIC BOOKS? Comic books aren't what they used to be but they continue to charm our children. By Mitch Finley '73

14 - STRESS, ILLNESS, AND PSYCHOTHERAPY The meaning of a stressful situation determines whether it is perceived as a challenge to be overcome or a demoralization. By Jerome D. Frank

18 - A BEELINE TO THE USA "Killer" bees have been winging their way from Brazil since scores of queens escaped a Sao Paolo lab in 1957. By Paul M. McCarthy '46

21 - PROMISE & OPPORTUNITY An economic forecast for the 1990s by …