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Articles 287041 - 287070 of 292936
Full-Text Articles in Physical Sciences and Mathematics
Stereoradiography As Applied To Problems Of Petrology., Martin Goldstone
Stereoradiography As Applied To Problems Of Petrology., Martin Goldstone
Masters Theses
"Stereoscopic examination of radiographs of rock and ore samples allows a rapid, cursory determination of texture and structure without time consuming preparation and use of thin sections. In addition, volumetric estimates of known mineral components can be made providing they possess significantly different x-ray absorption characteristics.
Stereoscopic effect was most pronounced for specimens having well defined components of structure such as bedding, banding, lineation, inclusions, textural variations and moderate to large x-ray absorption differences. In general, these conditions were best met by ores or ore minerals with their related gangue minerals.
Stereoscopic examination was not successful in revealing twinning or …
Hypogene Clay And Mica Minerals Associated With Fault Zones In The Ouachita Mountains-Arkoma Basin Area, Arkansas, Charles G. Stone
Hypogene Clay And Mica Minerals Associated With Fault Zones In The Ouachita Mountains-Arkoma Basin Area, Arkansas, Charles G. Stone
Journal of the Arkansas Academy of Science
No abstract provided.
Colorado River Storage Project, Glen Canyon Unit, Lake Powell, Area And Capacity Tables, Bureau Of Reclamation; United States
Colorado River Storage Project, Glen Canyon Unit, Lake Powell, Area And Capacity Tables, Bureau Of Reclamation; United States
Elusive Documents
No abstract provided.
Dissolved-Mineral Inflow To Great Salt Lake And Chemical Characteristics Of The Salt Lake Brine: Part 1- Selected Hydrologic Data, D. C. Hahl, C. G. Mitchell
Dissolved-Mineral Inflow To Great Salt Lake And Chemical Characteristics Of The Salt Lake Brine: Part 1- Selected Hydrologic Data, D. C. Hahl, C. G. Mitchell
Elusive Documents
No abstract provided.
Early Permian Fusulinids From Macusani, Southern Peru, Charles A. Ross
Early Permian Fusulinids From Macusani, Southern Peru, Charles A. Ross
Geology Faculty Publications
Triticites patulus Dunbar and Newell and Schwagerina adamsi sp. nov. from the early Wolfcampian (Permian) part of the Copacabana Group near Macusani, southern Peru, show morphological features that add new data concerning the evolution of the genera Schwagerina and Pseudoschwagerina from lineages arising within the genus Triticites near the close of the Pennsylvanian.
A Comparison Of Some Limnological Changes Caused By The Brookings Sewage Treatment Plant On Six-Mile Creek And The Big Sioux River, Richard Ruelle
A Comparison Of Some Limnological Changes Caused By The Brookings Sewage Treatment Plant On Six-Mile Creek And The Big Sioux River, Richard Ruelle
Electronic Theses and Dissertations
Introduction: In the days of the early pioneers in South Dakota and other sparsely settled areas, there was no problem in finding a sufficient supply of water for drinking, cooking, and washing purposes. The problems of waste disposal were taken care of by the microorganisms in the soil, the microorganisms easily being able to keep pace with the few settlers. As cities and towns began to form, usually along a stream where there was an abundant supply of fresh water, sewage disposal became a growing problem. The easiest way to get rid of the sewage was to dump it into …
Growth Rates Of Yellow Perch, Perca Flavescens (Mitchell), In Two North Dakota Lakes After Population Reduction With Toxaphene, Donald C. Warnick
Growth Rates Of Yellow Perch, Perca Flavescens (Mitchell), In Two North Dakota Lakes After Population Reduction With Toxaphene, Donald C. Warnick
Electronic Theses and Dissertations
Fishery waters overpopulated with desirable species generally produce few harvestable fish because of slow growth rates. In 1962 Bennett stated that no fish of harvestable were found in some waters thus affected. Eschmeyer (1936) made a similar observation concerning overcrowded populations of yellow perch (Perca flavescens). For lack of more efficient remedial measures the use of piscicides has been recommended to reduce the numbers the numbers of the problem species. Relatively low toxaphene concentrations in two North Dakota lakes substantially reduced the density of the yellow perch population the effect on other fish species was less obvious. The results reported …
Preparation And Properties Of 3, 3’ -Disbubstituted-2, 2’ – Three-Carbon-Atom Bridged Biphenyls, Allan E. Nader
Preparation And Properties Of 3, 3’ -Disbubstituted-2, 2’ – Three-Carbon-Atom Bridged Biphenyls, Allan E. Nader
Masters Theses
Introduction
The configuration of biphenyl has been treated in numerous articles and reviews (1, 5, 6, 7, 8, 16, 22, 23). In particular the configuration of 2,2'-bridged biphenyl derivatives has obtained attention. The synthesis of an optically active 2,2'-three-carbon-atom-bridged biphenyl possessing an ultraviolet absorption maximum at 250 mμ has been reported by Iffland and Siegel (15). These properties require first, a non-planar configuration for the molecule and second, significant inter-ring conjugation as demonstrated by ultraviolet spectra.
Several 2,2'-three-atom-bridged biphenyls have been prepared by Ahmed and Hall (2, 3) in order to obtain some measure of their specific rotation. The use …
Preparation Of The Cis And Trans Isomers Of Methylcyclohexanecarboxylic Acids And Their 2-Diethylaminoethyl Esters, Paul Allen Meulman
Preparation Of The Cis And Trans Isomers Of Methylcyclohexanecarboxylic Acids And Their 2-Diethylaminoethyl Esters, Paul Allen Meulman
Masters Theses
Introduction
The purpose of this research is to prepare the CIS and TRANS isomers of the 2, 3 and 4-methylcyclohecanecarboxylic acids and their 2-diethylaminoethyl esters.
This series of compounds is of interest because of the anti-tumor activity shown by some ethanolamine derivatives. The compounds to be prepared in this study represent modifications of these structures to determine if further investigation in this area is worthwhile. A pharmacological evaluation of these compounds will be made since many esters of amino alcohols have demonstrated pharmacological activity. The cancer chemotherapeutic and pharmacological test results are not included in this paper, but will be …
Rates Of Acidic Hydrolysis Of Triptych Boroxazolidines, Ronald Keith Stump
Rates Of Acidic Hydrolysis Of Triptych Boroxazolidines, Ronald Keith Stump
University of the Pacific Theses and Dissertations
Upon looking at the results of calculation of the rate constants given in Table 2, there are revealed some general trends as to the influence of the substituent groups on the values of the rate constants. If the rate constants of the reaction are considered at a fixed temperature, the rates of reaction in Group I decrease as the substituent is gradually changed from methyl to isopropyl. As soon as the substituent is changed from alkyl to an ether type,the rate of cleavage increases nearer to that of the parent compound again. The rate of cleavage of the nitrogen-boron bond …
1,3,5,7-Sym-Hydrindacentetrone And Its Derivatives, Irven Davies
1,3,5,7-Sym-Hydrindacentetrone And Its Derivatives, Irven Davies
University of the Pacific Theses and Dissertations
Three chapters of this dissertation, therefore,are devoted to describing the synthesis of 1,3,5,7-s-hydrinda-centetrone using the three starting materials, pyromellitic dianhydride by means of the four above described reactions.
1,3,5,7-s-Hydrindacentetrone, itself, and its properties are described in Chapter three when first prepared.
An entire chapter is devoted to the preparation of the dinitroso and dinitro derivatives; both because of the complexity of their reactions and because of their relative importance.
An additional chapter is devoted to other miscellaneous derivatives.
Conclusions have been drawn as to the appropriateness of each method of synthesis and are presented at the end of their respective …
A Progress Report On Commercial Cotton Growing On The Ord River Project, William John Toms
A Progress Report On Commercial Cotton Growing On The Ord River Project, William John Toms
Journal of the Department of Agriculture, Western Australia, Series 4
The recommendations given in this article have been built up from the experience of the author in growing 200 acres of cotton in the Ord River area during the 1962-63 season for the Department of Agriculture, from findings made by Kimberley Research Station, and from discussions with the present farmers in the area.
When a new form of agriculture is introduced into a new area techniques and ideas change rapidly as farmers become acquainted with their new environment and the new crops. The recommendations will therefore require constant revision.
The Bdellidae (Acarina) Of The Australian Realm, Warren T. Atyeo
The Bdellidae (Acarina) Of The Australian Realm, Warren T. Atyeo
Bulletin of the University of Nebraska State Museum
Although primarily a systematic study, variations in the integumental striae and chaetotaxy of the legs are discussed. The genus Octobdellodes Atyeo, 1960 is synonymized with Bdellodes Oudemans, 1937 and the sugenus Cytobdella Mihelcic, 1958 is synonymized with Cyta von Heyden, 1826. The genus Bdellodes is divided into the subgenera Bdellodes and Hoploscirus Thor, 1937 (=Thoribdella Grandjean, 1938, new synonymy). Twenty-two species are now known to occur in New Zealand and the outlying islands. These include four known species: Bdella iconica, Bdellodes (Roploscirus) lapidaria, B. (R.) reticulata, and Cyta latirostris, and eighteen new species: Bdellodes (Bdellodes) harpax, B. (B.) oraria, …
Deltoptila, A Middle American Genus Of Anthophorine Bees (Hymenoptera, Apoidea), Wallace E. Leberge, Charles D. Michener
Deltoptila, A Middle American Genus Of Anthophorine Bees (Hymenoptera, Apoidea), Wallace E. Leberge, Charles D. Michener
Bulletin of the University of Nebraska State Museum
A third genus in the tribe Anthophorini in the vI/estern Hemisphere, genus Deltoptila, is described in this work. Previously described species included in the genus are as follows: D. melanopyrrha (Dours), D. elefas (Friese), D. fulva (Smith), D. bombyformis (Smith), D. montezumia (Smith), D. aurulentocaudata (Dours), D. agilis (Smith), D. costaricensis (Friese). New descriptions and records are given for D. montezumia, D. aurulentocaudata, D. agilis and D. costaricensis. Two new species are described: D. afimbriata and D. pexata.
New Species And Records Of Little-Known Species Of Melissodes From North America (Hymenoptera: Anthophoridae), Wallace E. Laberge
New Species And Records Of Little-Known Species Of Melissodes From North America (Hymenoptera: Anthophoridae), Wallace E. Laberge
Bulletin of the University of Nebraska State Museum
Two new species from Mexico, Melissodes (Tachymelissodes) sonorensis and M. (Melissodes) tescorum, are described in this paper. The previously undescribed males of M. cerussata LaBerge and M. baileyi Cockerell are described. Notes concerning the key to species of the subgenus Callimelissodes are given. New records of the following poorly known species of Melissodes are included: M. opuntiella, M. sphaeralcea, M. fimbriata, M. baileyi, M. apicata, M. mitchelli, M. intorta, M. flexa, M. maesta, M. cerussata, M. expolita, M. fasciatella, M. floris, M. …
The F.A.Q. Standard For 1962-63, Department Of Agriculture, Western Australia
The F.A.Q. Standard For 1962-63, Department Of Agriculture, Western Australia
Journal of the Department of Agriculture, Western Australia, Series 4
THE term f.a.q. refers to "fair average quality" as a standard for the sale of wheat -*- produced in Western Australia during any particular season.
The practice of using this standard developed after a standard sample of wheat grown in 1904 was obtained and declared to have a bushel weight of 62 lb.
The Hydrometallurgy Of Uranium, John E. Cesarani
The Hydrometallurgy Of Uranium, John E. Cesarani
Bachelors Theses and Reports, 1928 - 1970
No abstract provided.
Determination Of Thallium(Iii) Using The Dead-Stop End Point, Richard Blount Williams
Determination Of Thallium(Iii) Using The Dead-Stop End Point, Richard Blount Williams
University of the Pacific Theses and Dissertations
An accurate and fairly rapid method of analysis of thallium solutions is desirable in order to facilitate further investigation of the chemistry of thallium. The dead-stop titration method which has been successfully applied to other metals of Group 3b, will not be applied to the quantitative determination of the thallium (III) ion in aqueous solution.
Hydrolysis Of Alpha-D-Glucosamine-L-Phosphate, Michael James Pizanis
Hydrolysis Of Alpha-D-Glucosamine-L-Phosphate, Michael James Pizanis
University of the Pacific Theses and Dissertations
Some information on the hydrolysis mechanism of phosphate esters was obtained by studying the kinetics of ∝-D-Glucosamine-1-phosphate.
∝-D-Glucosamine-1-phosphate was synthesized, an experimental pH-rate profile for the hydrolysis of this phosphate was determined at 100 C.
It was proposed that Species I (see page 7) had P-O cleavage with intramolecular proton transfer to ester oxygen. Species II is believed to have the same mechanism of hydrolysis as monoanion of methyl phosphate and monoanion of ∝-D-Glucosamine-1-phosphate. This study indicates that Species III s reactive, while the dianion of methyl phosphate and the dianion of ∝-D-Glucosamine-1-phosphate are inactive. The increased reactivity of Species …
Atomism In Late Nineteenth-Century Physical Chemistry, George Fleck
Atomism In Late Nineteenth-Century Physical Chemistry, George Fleck
Chemistry: Faculty Publications
No abstract provided.
An Introduction To The Analytical Study Of Mercury (Ii) Ion - Thiazate Complex, Jess Horlanda Reyes
An Introduction To The Analytical Study Of Mercury (Ii) Ion - Thiazate Complex, Jess Horlanda Reyes
University of the Pacific Theses and Dissertations
The problem involved in this research was to characterize some of the chemical and physical properties of thiazate through analytical procedure. At most, this thesis is a report of the findings when this compound reacts with mercury (II) ions in basic solutions. The methods of investigation made use of the Beckman Model DS and DU spectrophotometers, and the Beckman pH meter.
An Experimental Investigation Of Coloring Matter In Flowers Of Vinca Major, Alin Haykohi Gulbenk
An Experimental Investigation Of Coloring Matter In Flowers Of Vinca Major, Alin Haykohi Gulbenk
University of the Pacific Theses and Dissertations
Even though early man did not know the nature of coloring matter in flowers, he used the coloring matter as dye for centuries. There are a variety of reasons for the interest of chemists in natural and artificial coloring matters. One of these is the color pleasure, anothe1· is the commercial importance. The visible color facilitates the experimental work in the search for methods if separation, purification and determination of organic structures.
Search for the knowledge of coloring matter goes far back in history. Man has dyed his textiles with the help of mordants from the most ancient times up …
Construction And Initial Testing Of A Microwave Spectrometer, Thomas Willard Duecker
Construction And Initial Testing Of A Microwave Spectrometer, Thomas Willard Duecker
University of the Pacific Theses and Dissertations
This thesis has been written to provide a basic understanding of the spectrometer and to be used as a useful reference for its operation. Discussions of such things as the propagation of microwaves and the mechanics of klystron operations have been avoided.
Control Of Copper, Zinc And Manganese Deficiencies In Fruit Trees, N J. Halse
Control Of Copper, Zinc And Manganese Deficiencies In Fruit Trees, N J. Halse
Journal of the Department of Agriculture, Western Australia, Series 4
THE three elements copper, zinc and manganese are plant nutrients of the type often referred to as minor or trace elements.
Although essential elements for plant growth, they are required in comparatively small quantities.
A Practical Guide To Building Contour Banks With A Road Grader, J E. Watson
A Practical Guide To Building Contour Banks With A Road Grader, J E. Watson
Journal of the Department of Agriculture, Western Australia, Series 4
THOUSANDS of miles of contour banks have been built in Western Australia, and most of this earthmoving has been done by tractor and disc plough* or by road grader.
This article describes the technique recommended for bank construction with the road grader.
Swing Fence Flood Crossing For Creeks In The Kimberleys, A L. Payne
Swing Fence Flood Crossing For Creeks In The Kimberleys, A L. Payne
Journal of the Department of Agriculture, Western Australia, Series 4
FENCING is the basis of the regeneration programme on the eroded Ord River catchment area, and the fences constructed must cross numerous creeks.
But heavy downpours of short duration characterise the wet season experienced in this area.
Because the rain falls on to bare, compacted ground, run-off is intense and gullies and creeks rise rapidly, causing serious damage to conventional fences and flood gates across watercourses.
Hydroxy Derivatives Of Benzalthiophenone, John M. Newey
Hydroxy Derivatives Of Benzalthiophenone, John M. Newey
University of the Pacific Theses and Dissertations
It is the purpose of this work to prepare a series of these chalcones containing the thiophene ring.
The compounds were prepared by the condensation of a series of benzaldehydes with acetylthiophene dissolved in dry ethylacetate and saturated with dry HCl. The benzaldehyde compounds were benzaldehyde, m-hydroxybenzaldehyde, o-hydroxybenzaldehyde, O-p-dihydroxybenzaldehyde and vanillin. To prevent the oxidation of the hydroxy groups of the benzaldehydes, the compounds were benzolated with benzoylchloride. The condensed products were debenzoylated with NaOH solution in an atmosphere of nitrogen to prevent oxidation during the debenzoylation process.
High Frequency Titrations In Liquid Ammonia, Jack Charles Hileman
High Frequency Titrations In Liquid Ammonia, Jack Charles Hileman
University of the Pacific Theses and Dissertations
An extensive literature has been established on the use of high frequency conductometric methods in chemical analysis and research. The fact that the instruments respond to chemical changes without having electrodes immersed in the reacting solutions has attracted the attention of many investigators. Until the last few years, practically all of the investigations were concerned with aqueous solutions, with the exception of measurements of dielectric constants.
There seemed no logical reason for not extending the use of the high frequency instruments to the study of Bronsted acid-base reactions, organic syntheses, rates of reaction, and the other commonly studied aspects of …
High Temperature Adsorption Studies On Solid Adsorbents, Julian Joseph Hamerski
High Temperature Adsorption Studies On Solid Adsorbents, Julian Joseph Hamerski
University of the Pacific Theses and Dissertations
It has been found that there exist certain crystalline aluminosilicates which provide regular net-works of channels with diameters no bigger than those of molecules. Such crystals can act as sieves (thus the name "molecular sieves" now marketed by the Linde Air Products Company) and bring about a separation of molecular species by occluding small molecules while not adsorbing larger molecules or molecules with shapes that do not "fit."
The aluminosilicates were termed zeolites first by Baron Cronstedt (1) some 200 years ago. He observed that certain mineral crystals, when heated, appeared to melt and to boil at the same time. …
Diffusion In A Low-Velocity, Inshore Tidal Current Off Virginia Beach, Virginia, Wyman Harrison, Virginia Institute Of Marine Science
Diffusion In A Low-Velocity, Inshore Tidal Current Off Virginia Beach, Virginia, Wyman Harrison, Virginia Institute Of Marine Science
Reports
No abstract provided.