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Articles 77491 - 77520 of 78533
Full-Text Articles in Entire DC Network
Terminal Talk - The Wofford Connection - July 1970, Wofford College Computer Center
Terminal Talk - The Wofford Connection - July 1970, Wofford College Computer Center
Terminal Talk
No abstract provided.
Hellmann-Feynman Theorem In Thomas-Fermi And Related Theories, Jerry Goodisman
Hellmann-Feynman Theorem In Thomas-Fermi And Related Theories, Jerry Goodisman
Chemistry - All Scholarship
The general Hellmann-Feynman theorem (derivative of energy with respect to a parameter = expectation value of derivative of Hamiltonian) is proved for theories in which the electron density is determined by making the energy functional stationary. Some simple applications are given.
Erasure Of Sediment Surface Features By Mellita Quinquiesperforata (Leske), Walter Richard Boehmer
Erasure Of Sediment Surface Features By Mellita Quinquiesperforata (Leske), Walter Richard Boehmer
OES Theses and Dissertations
Erasure of sediment surface features by individuals of the species, Mellita guinguiesperforata, observed in this study suggests that all members of the sub-order, Scutellina, are able to erase sediment surface features. Sweep time, the time needed to erase the surface features of an area, depends on the population density, individual size, and speed of movement of the sand dollars. Assuming their pattern of movement as random, the following equation can be used to determine sand dollar sweep time,
T - 3.2 N-0.76 (W / S) (A/ W2 )1.21
where T is sweep time, N is the …
A Spectroscopic Investigation Of Electron Transfer Transitions In Osmium (Ii) Complexes, Brian J. Pankuch
A Spectroscopic Investigation Of Electron Transfer Transitions In Osmium (Ii) Complexes, Brian J. Pankuch
Chemistry and Chemical Biology ETDs
Osmium (II) complexes containing organic coordinating ligands 2.2'-bipyridine, 1.10-phenanthroline, 2.2' .2"terpyridine were studied spectroscopically. Syntheses were carried out by published methods, and each complex was checked by chemical analysis and thin layer chromatography. The complexes were shown to be d6 strong field systems by magnetic susceptibility measurements performed at room temperature in air.
Room temperature absorption spectra in the visible and near-ultraviolet were measured in solvents of different polarities (H2O, MeOH, CH3CN, DMF, CHCl3) and solvent shifts of the band maxima of 0.3 to 3 kK were found. Low temperature (approximately 82-90°K) absorption spectra …
A Preliminary Survey Of The Damariscotta River Estuary, Lincoln County, Maine, Maine Department Of Economic Development
A Preliminary Survey Of The Damariscotta River Estuary, Lincoln County, Maine, Maine Department Of Economic Development
Maine Collection
A Preliminary Survey of the Damariscotta River Estuary, Lincoln County, Maine
Part I - Hydrology; Part II - Sediments
"Prepared Under a Grant From the Maine Marine Stipend Program".
Maine Department of Economic Development - Division of Science, Technology & Mineral Resources, Augusta, Maine (July 1969 - June 1970).
The Monadnock Volume 44, June 1970, Clark University Geographical Society
The Monadnock Volume 44, June 1970, Clark University Geographical Society
The Monadnock (Clark Geographical Society)
Volume 44 of The Monadnock. The Monadnock was the alumni magazine of the Clark University Geographical Society (1927-1985) (2014-present).
The Prairie Naturalist Volume 2, No.2 June, 1970
The Prairie Naturalist Volume 2, No.2 June, 1970
The Prairie Naturalist
EDITORIAL: Ecocide on the Sheyenne? ▪ Paul B. Kannowski
NEW RECORDS OF VASCULAR PLANTS IN NORTH DAKOTA ▪ Robert E. Stewart
SOME LOCAL NATIVE PLANT LOSSES AND SOME SAL V AGE ▪ O. A. Stevens
CHRISTMAS BIRD COUNTS IN NORTH DAKOTA ▪ Robert N. Randall
ENVIRONMENTAL DESIGN IN COMMUNITY PLANNING ▪ Cameron Man
DISTRIBUTION OF THE SCIRPUS VALIDUS COMPLEX IN NORTH DAKOTA ▪ Richard L. Ward
Preparation Of New Amino-, Thio-, And Sulfonyladamantane Derivatives, Joseph Craig Argyle
Preparation Of New Amino-, Thio-, And Sulfonyladamantane Derivatives, Joseph Craig Argyle
Theses and Dissertations
Various synthetic schemes were used to prepare a number of new amino-thio- and sulfonyladamantane compounds. By a nucleophilic substitution on 1-bromoadamantane, 1-(p-nitrophenylthio)adamantane was prepared from p-nitrothiophenol; the amino- and sulfonyl- derivatives of this compound were also prepared. Silver tosylate was used to generate the 1-adamantyl carbonium ion from 1-bromoadamantane in a synthetically useful procedure for preparing 1-adamantylamides from nitriles. Three 1-(1-adamantylcarbinyl)-2,5-dialkylpyrroles were prepared by Knorr-Paal reactions and reduced to the corresponding pyrrolidines. Thio- and aminomethyl 1-adamantyl ketones were prepared from methyl and bromomethyl 1-adamantyl ketones, respectively. Aliphatic and aromatic oxiranes were reacted with 1-aminoadamantane in a bomb at elevated temperatures …
The Enzymatic Oxidation Of Aldehydes By Xanthine Oxidase, Duane Beal Gregory
The Enzymatic Oxidation Of Aldehydes By Xanthine Oxidase, Duane Beal Gregory
All Master's Theses
As early as sixty years ago, the existence of an enzyme from mammalian tissues which catalyzed the oxidation of xanthine and hypoxanthine was recognized. The name given the enzyme was derived from its earliest recognized action, hence xanthine oxidase. Although little is known about the biological functions of the enzyme, the high affinity shown for xanthine and hypoxanthine may indicate that these are the most significant substrates biologically.
The Synthesis And Properties Of New Potentially Chemotheraputic [Sic] Pteridine Derivatives, Walter Wesley Parish
The Synthesis And Properties Of New Potentially Chemotheraputic [Sic] Pteridine Derivatives, Walter Wesley Parish
Theses and Dissertations
A new general synthetic method for the preparation of 6-thiopteridines has been developed. The method involves the addition of thiols to intermediate pyrimidine nitrones formed in situ by the reaction of 4-amino-5-nitrosopyrimidines with pyridinium-activated acetonitriles, acetates, acetophenones, and other methylketones. Ca. forty new pteridines were prepared by this method. The preparation of six new 6-pteridinyl ketones, two new 6- pteridinyl ketone thiosemicarbazones, and two new 6-sulfonylpteridines and their 4-acetamido derivatives is also reported. 4-Acetamido-2- amino-7-phenylpteridine 5-oxide was prepared by the reaction of 2- amino-4,6-diacetamido-5-nitrosopyrimidine with either phenylsulfonyl-acetophenone or phenacylpyridinium bromide. Evidence relating to the structure of the acylated 4-amino-5- nitrosopyrimidines …
Record In Rock: A Handbook Of The Invertebrate Fossils Of Nebraska, Roger K. Pabian
Record In Rock: A Handbook Of The Invertebrate Fossils Of Nebraska, Roger K. Pabian
Conservation and Survey Division: Faculty and Staff Publications
Table of Contents:
Introduction
What Are Fossils? How Do They Form?
Fossilization
How Are Fossiliferous Rocks Formed?
What is Paleontology?
What Can Fossils Tell Us?
Fossils and Geologic Time
Fossils as Environmental Indicators
Fossils and Conservation
How Are Fossils Named?
Where Are Fossils Found?
Collecting Courtesy
Tools for Collecting Fossils
Tips on Collecting Fossils
Safety Rules
Quarry Safety
Safety Don'ts to Remember
Preparation of Specimens
A Bit of Advice
General Characteristics of Nebraska's Important Fossils
Phylum Protozoa (Single-Celled Animals)
The Living Protozoan
Fossil Protozoans from Nebraska
Phylum Porifera (Pore Bearers or Sponges)
The Living Sponge
Fossil Sponges from Nebraska
Phylum …
An In Vivo Perfusion Apparatus For Studies On Gingival Disease In The Albino Rat : Assessment By A Perfusion Of The Enzymes Collagenase And Hyaluronidase, James A. Smith
Loma Linda University Electronic Theses, Dissertations & Projects
This thesis describes an in vivo perfusion apparatus which can continuously deliver controlled quantities of solutions to localized, contralateral intraoral areas in albino rats. Three animals were per fused on the experimental area (the mesial sulcular area of the maxillary first molar) on one side with tap water and Trypan blue. Localization of the solution delivered and minimal histological changes due to the presence of the apparatus was demonstrated on these animals. Solutions of .5%, 1%, and 2% hyaluronidase and collagenase were perfused on the experimental areas of nine animals. When both enzymes were used, hyaluronidase always preceded collagenase in …
Molecular Luminescence From Turhenium, Osmium, And Terbium Chelates: 2°K To 300°K, Raymond William Harrigan
Molecular Luminescence From Turhenium, Osmium, And Terbium Chelates: 2°K To 300°K, Raymond William Harrigan
Chemistry and Chemical Biology ETDs
Two experimental spectroscopic investigations spanning the temperature range 300°K to 2°K were carried out on molecular complexes. The nature of charge-transfer phenomena in transition-metal chelates was studied extensively, and the thermal quenching of the luminescence of terbium (III) chelates was briefly investigated. The experimental methods employed were absorption and luminescence spectroscopy including photoflash excitation for studying transient luminescence decays. Measurements were performed on three osmium and three ruthenium complexes, all containing bidentate or tridentate heterocyclic aromatics as ligands. The compounds were studied in rigid solvent glasses, in poly(methyl methacrylate) (PMM), in an isomorphic host of tris(2, 2'-bipyridine)zinc(II) sulfate, and in …
The Historic End Of Closed Seas, James Edward Grise
The Historic End Of Closed Seas, James Edward Grise
Marine Affairs Theses and Major Papers
The purpose of this paper is to consider the rather vague claims to closed seas by the Soviet Union and to determine what direction these claims are taking. The first part of the paper deals with the history and development of the closed seas concept and expands it into the present day claims in this area. It attempts to show how some of the past claims have remained over the years and how some of the others have progressed to claims of historic waters. In the final section an attempt is made to show some method for resolving some of …
Natural Sovereignty On The High Seas, Thomas Arthur Marnane
Natural Sovereignty On The High Seas, Thomas Arthur Marnane
Marine Affairs Theses and Major Papers
The purpose of this paper is to examine a current dispute involving resources in the sea, determine the issues involved, and hypothesize a solution. Specifically, the dispute chosen involves Latin American claims to extensive sovereign fishery rights in adjacent coastal waters and objections to these claims. The United States and the parties to a declaration made in Santiago, Chile, in 1882, Chile, Ecuador, and Peru, have been chosen as most representative of the opposing positions. The International Court of Justice, primarily utilizing as a framework for analysis the dicta, findings, and opinions in their February 1969 Judgment in the North …
A Dialyzable Phospholipid Renin Inhibitor, Donna L. Webber
A Dialyzable Phospholipid Renin Inhibitor, Donna L. Webber
Senior Scholar Papers
Crude renin preparations from steer kidneys were incubated with Cd2+ and with Zn2+ elevation of renin activity resulted in both preparations. Analyses of each preparation against Tris-saline, and finally EDTA, removed the cations; however, renin activity remained elevated. An indirect activation of Renin by Cd2+ and, to a lesser extent, Zn2+, was thus demonstrated. Removal of the cations by Tris-saline and DTA-dialyses was suspected to involve the loss by dialysis of a renin inhibitor. An isolation technique for a proposed phospholipid renin inhibitor similar to bovine phosphatidylserine, reported by another laboratory, was thought to be unnecessarily arduous due to the …
The Ias Bulletin, V4n3, May 1970, Iowa Academy Of Science
The Ias Bulletin, V4n3, May 1970, Iowa Academy Of Science
IAS Bulletin
In this issue:
--- Officers, Directors, and Section Chairmen, 1970-71
--- 82nd Facts and Figures
--- Section Attendance
--- New Constitution Adopted
--- Concerning the Dues Increase
--- Abstracts Available
--- Election Results
--- New Standing Committees
--- New Proceedings Policies in 1971
--- Annual Report
--- New Members Since March
The Ontogeny Of Social Behavior Of Uinta Ground Squirrels, D. Andrew Saunders
The Ontogeny Of Social Behavior Of Uinta Ground Squirrels, D. Andrew Saunders
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The social behavior of juvenile Uinta ground squirrels (Spermophilus armatus) was studied for 2 1/2 years in northeastern Utah. The purpose of the study was to describe the developing social behavior of unconfined, marked squirrels. Their behavior was recorded with motion pictures and written descriptions from the time they emerged from the natal burrow until they entered hibernation.
Three phases of behavioral development were apparent. The first phase began when the juveniles appeared above ground and ended 5 weeks later. This was a period of socialization and consisted of behavioral patterns best described as play. The second phase …
Nonparametric Test Of Fit, Frena Nawabi
Nonparametric Test Of Fit, Frena Nawabi
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
Most statistical methods require assumptions about the populations from which samples are taken. Usually these methods measure the parameters, such as variance, standard deviations, means, etc., of the respective populations. One example is the assumption that a given population can be approximated closely with a normal curve. Since these assumptions are not always valid, statisticians have developed several alternate techniques known as nonparametric tests. The models of such tests do not specify conditions about population parameters.
Certain assumptions, such as (1) observations are independent and (2) the variable being studied has underlying continuity, are associated with most nonparametric tests. However, …
A Study To Demonstrate The Immediate Destination Of An Embolus Formed In The Lumen Of A Peripheral Venous Catheter, Rosemarie Morikone Emori
A Study To Demonstrate The Immediate Destination Of An Embolus Formed In The Lumen Of A Peripheral Venous Catheter, Rosemarie Morikone Emori
Loma Linda University Electronic Theses, Dissertations & Projects
This study was designed to show the immediate destination of an embolus formed in the lumen of an intravenous catheter placed in a peripheral vessel. The hypothesis stated that clots injected into a peripheral vessel will lodge in the lungs. A subhypothesis was that the clot may lodge anywhere along the circulatory pathway.
Indications of need for the study as shown by the review of literature were the following: (1) the complications resulting from the frequent use of intravenous polyethylene catheters, (2) experimental studies that showed that clots were formed around intravenous catheters, (3) the evidence that intravenous catheters predispose …
Periodontal Pocket Reduction Following Gingival Curettage, Robert B. Tandy
Periodontal Pocket Reduction Following Gingival Curettage, Robert B. Tandy
Loma Linda University Electronic Theses, Dissertations & Projects
The purpose of this study was to evaluate pocket reduction following gingival curettage. The effects of temporary pressure packing, inflammation, oral hygiene, pocket depth, age and sex of the patient were evaluated.
Three hundred twenty-eight periodontal pockets were studied in forty-one adult patients selected with interdental lesions ranging from 3.0 - 7.5 mm. in depth. Pocket depth and gingival height were measured preoperatively, one month postoperatively and two months postoperatively. The mean change in pocket depth and gingival height was calculated and statistical significance was determined for all measurements.
The results show that after a two-month postoperative evaluation following gingival …
Areal And Temporal Variations In Developmental Phases Of Syringa Vulgaris L. Throughout The Western United States, Joseph Michael Caprio
Areal And Temporal Variations In Developmental Phases Of Syringa Vulgaris L. Throughout The Western United States, Joseph Michael Caprio
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This paper presents the results of the analysis of 10 years of information 1957-1966 on three phases-- begin, peak and end bloom-- of the purple common lilac (Syringa vulgaris L.) using data recorded at approximately 1,000 locations throughout the Western Region of the United States.
The pattern of geographical advance of the various bloom phases is determined by both a manual mapping procedure developed by the author and by standard statistical methods. Manually drawn isophanes for the various elevations for begin bloom phase are based entirely upon the first 5 years of record, 1957-1961. A Zones of Adjustment map to …
Drift Of Oligophlebodes Sigma And Baetis Bicaudatus In A Mountain Stream, William Dean Pearson
Drift Of Oligophlebodes Sigma And Baetis Bicaudatus In A Mountain Stream, William Dean Pearson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The objective of this study was to clarify the relationships between drift rates, population density, production rates, key environmental factors, and movements of adults within two populations of stream insects (a caddisfly--Oligophlebodes sigma and a mayfly--Baetis bicaudatus).
Samples of benthic invertebrates (424 total) were collected every 28 days at four stations on Temple Fork of the Logan River, Utah, from October, 1967 to September, 1969. Samples of drift invertebrates (181 total) were collected every 14 days at three stations on Temple Fork during the same period. During summer months (June-September) a day and a night drift sample …
The Effect Of Chemical Competition On Thermodynamics Of Bacterial Adsorption, Deorao R. Khairnar
The Effect Of Chemical Competition On Thermodynamics Of Bacterial Adsorption, Deorao R. Khairnar
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The objective of this investigation was to study the effect of chemical competition on thermodynamics of bacterial adsorption. This was done using an experimental system consisting of Mendon silt loam soil as the adsorbent, Staphylococcus aureus as a common adsorbate and sodium chloride (NaCl), sodium lauryl sulfate (SLS), and peptone as competitive adsorbates.
The bacterial adsorption on soil both with and without chemical competition followed Langmuir type isotherms. From the equilibrium data, thermodynamic functions such as free energy, ΔF°, enthalpy, ΔH°, and entropy, ΔS°, were calculated. Observed positive ΔH° values indicated that the bacterial uptake in both noncompetitive and competitive …
Magnesium Ion Inhibition Of Calcium Carbonate Precipitation And Its Relation To Water Quality, John J. Hassett
Magnesium Ion Inhibition Of Calcium Carbonate Precipitation And Its Relation To Water Quality, John J. Hassett
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The effect of Mg++ ion on the solubility of calcium carbonate was determined using P. K. Weyls "carbonate saturometer."
The amount of calcium carbonate precipitated or dissolved was measured for five series of waters when equilibrated with solid carbonate.
It was found that the effect of Mg++ ion on solubility depend upon the nature of the solid phase: surface area, coprecipitated Mg++, minerology, etc.
Pure low area calcite showed an increase in solubility which could be explained by ion-pair formation, while its other carbonates departed from this behavior.
Evaluation Of Molting Areas Of Great Basin Canada Geese, Paul D. Arneson
Evaluation Of Molting Areas Of Great Basin Canada Geese, Paul D. Arneson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Environmental factors at Neponset and Woodruff Narrows reservoirs were evaluated to determine their effects on molting Canada geese. More geese utilized Woodruff Narrows. Geese apparently favored the larger expanse of open water and adequate food supply.
Most of the molting geese were from the Bear River drainage. Some geese came from scattered areas in Utah, Idaho, Wyoming, and Montana. After molting, the geese flew to migration staging areas in southeastern Idaho before migrating to wintering areas in southern California and Arizona.
Females outnumbered males by 6 percent. The mean annual mortality rate for adult geese was 42 percent. Recovery rates …
The 82nd Session Of The Iowa Academy Of Science And The 38th Convention Of The Iowa Junior Academy Of Science, April 24-25, 1970, Iowa Academy Of Science
The 82nd Session Of The Iowa Academy Of Science And The 38th Convention Of The Iowa Junior Academy Of Science, April 24-25, 1970, Iowa Academy Of Science
Iowa Academy of Science Documents
No abstract provided.
82nd Session Of The Iowa Academy Of Science, April 24-25, 1970, Iowa Academy Of Science
82nd Session Of The Iowa Academy Of Science, April 24-25, 1970, Iowa Academy Of Science
Iowa Academy of Science Documents
No abstract provided.
Recommendations For A United States Position Regarding Delimitation Of The Outer Boundary Of The "Legal" Continental Shelves, Brian K. Hannula
Recommendations For A United States Position Regarding Delimitation Of The Outer Boundary Of The "Legal" Continental Shelves, Brian K. Hannula
Marine Affairs Theses and Major Papers
The Convention on the Continental Shelf has come under attack because it does not establish a precise outer boundary for the "legal" continental shelf. It is the author's opinion that the United States should propose or support a revision of the Convention which would rectify this situation. A suitable delimitation proposal must have considerable domestic support and should represent the best compromise between opposing domestic views. A proposed revision of the Convention must, also, have strong international support if it is to be adopted. Each nation will determine a preferred delimitation which depends on the configuration of its own continental …
State Of The Fisheries Report 1968/1969, Department Of Fisheries And Fauna, Western Australia
State Of The Fisheries Report 1968/1969, Department Of Fisheries And Fauna, Western Australia
Status Reports of the Fisheries and Aquatic Resources
The total value of the fisheries of Western Australia is the highest of any of the States, and the Western Australian rock lobster fishery is the most valuable single fishery in Australia.