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Articles 57211 - 57240 of 58458
Full-Text Articles in Entire DC Network
On The Scintillation Of Stars., Mary Elizabeth Prince Phelan
On The Scintillation Of Stars., Mary Elizabeth Prince Phelan
Physics & Astronomy ETDs
The nature of stellar scintillation is important to the astronomer and to the atmospheric physicist, but little quantitative work has been done in this area. This paper describes the results of an objective study of stellar scintillation. The principle measurements were concerned with a determination of the scintillation pattern and rate of a star which was observed simultaneously in two photoelectric telescopes whose distance could be varied. Other items measured included variations in rate of scintillation with: stellar magnitude, stellar altitude, atmospheric changes, and time of evening.
Ultrasonic Suspension Of Liquid Droplets For Light Scattering Studies, David L. Cutchin
Ultrasonic Suspension Of Liquid Droplets For Light Scattering Studies, David L. Cutchin
Physics & Astronomy ETDs
The construction and operation of an ultrasonic liquid droplet suspension device are described. The problem of generating intense sonic waves by matching the sonic transducer components is investigated. There is a description and analysis of a light scattering experiment performed on a suspended water droplet. The moat prominent characteristic of the scattered light was a rapid (10 to 100 cycles per second) time fluctuation in intensity. The variation in scattering cross section with droplet diameter predicted by the Mie theory and droplet shape oscillations are investigated as possible mechanisms producing the fluctuations.
Measuring Spin-Lattice Relaxation Times With A Super-Regenerative Spectrometer, Alfred C. Rester Jr.
Measuring Spin-Lattice Relaxation Times With A Super-Regenerative Spectrometer, Alfred C. Rester Jr.
Physics & Astronomy ETDs
Nuclear quadrupole resonance is a branch of radio frequency spectroscopy which was discovered in 1950 by Dehmelt and Kruger. (1). It is concerned with radio-frequency magnetic resonance absorption in molecular crystals. It results from the interaction of the nuclear quadrupole moment with the electric field gradient of the molecule charge cloud surrounding the nucleus. Different orientations of the nuclear axis relative to the field axis correspond to different energy levels. Resonance absorption takes place when an applied electromagnetic field cause transitions from one energy level to a higher one.
A Gated Digital Integrator And Its Application To The Measurement Of Nuclear Quadrupole Relaxation Times, Jack Curtis Wilcott
A Gated Digital Integrator And Its Application To The Measurement Of Nuclear Quadrupole Relaxation Times, Jack Curtis Wilcott
Physics & Astronomy ETDs
The thesis is divided into two sections. The first section discusses nuclear quadrupole resonance, relaxation times, experimental procedure, and apparatus, and some data is given. The second section describes the gated digital integrator in detail. The system uses the boxcar integrator technique for analyzing periodic waveforms obscured by noise. The average voltage of a small segment of the waveform is obtained by repeated sampling and is stored in a digital up-down counter. A digital-to-analog converter converts the stored digital number into a voltage to run a recording meter and to provide a feedback signal to compare with the input signal. …
Proton Measurements On A Rocket Probe Into The South Atlantic Radiation Anomaly, Russell G. Herron
Proton Measurements On A Rocket Probe Into The South Atlantic Radiation Anomaly, Russell G. Herron
Physics & Astronomy ETDs
1. Geomagnetically Trapped Radiation
A summary of results of space measurements during the 1950's has been published by Rossi (reference 1). Foremost among these results was the discovery of geomagnetically trapped radiation observed in increased counting rates in geiger counters on Sputnik II and Explorer I. In 1958, Van Allen (reference 2) correctly interpreted these experiments in terms of belts of geomagnetically trapped particles. In 1961, Singer and Lenchek (reference 3) reviewed progress in the burgeoning field of geomagnetically trapped radiation. In September 1962, Rosen et al. (reference 4) summarized the accepted information on the space radiation environment in a …
An Investigation Of Neutron Collimators And Their Application In Neutron Radiography., Roger A. Morris
An Investigation Of Neutron Collimators And Their Application In Neutron Radiography., Roger A. Morris
Physics & Astronomy ETDs
One of the most important diagnostic tools in the fields of medicine and industry is the use of penetrating radiation to detect flaws, inhomogeneities, and abnormal conditions within an object without permanently changing or destroying the object being inspected. The equipment, technique, and type of radiation employed vary widely between hospital, shop, or laboratory depending upon the particular conditions that are encountered and the results that are expected. Probably the most widely used radiation types are X-rays or gamma-rays and their applications in the above-mentioned fields need no further description. However, beams of thermal neutrons are becoming more and more …
The Synthesis Of Condensed Pyridazines And Related Nitrogen Heterocycles As Potential Anticancer Agents, G. Anne Gerhardt
The Synthesis Of Condensed Pyridazines And Related Nitrogen Heterocycles As Potential Anticancer Agents, G. Anne Gerhardt
Chemistry and Chemical Biology ETDs
The antitumor activity found in such ring systems as purine (I), 8 - azapurine (II), pyrazolo[3, 4- d]pyrimidine (Ill) and pteridine (VI) prompted the preparation of substituted benzimidazoles, ν-triazolo[4, 5-c]- (V), imidazo[4, 5-d]- (IV), pyrazino[2, 3-c]- (VII) and pyrazino[2, 3-d]- (VIII) pyridazines.
The Facial Complex Of The Mayo Indian: A Radiographic Cephalometric Study, David G. Webster
The Facial Complex Of The Mayo Indian: A Radiographic Cephalometric Study, David G. Webster
Loma Linda University Electronic Theses, Dissertations & Projects
In order to investigate the characteristics of the facial complex of the Mayo Indian and to make comparisons between the facial complex of the Mayo Indian and the facial complex observed in other ethnic groups, measures of facial angles and linear relationships were obtained from a group of Mayo Indians in the state of Sonora, Mexico.
A simple of thirty subjects, seventeen boys and thirteen girls, with a mean age of 18.3 years was selected for this study. The criteria for selection was based on the integrity of the dental arches, occlusion and tooth morphology. Plaster casts and cephalometric x-rays …
A Comparative Study Of Discomfort Experienced By Surgical Patients On Three Selected Postoperative Days, Lillian Barker Bartlett
A Comparative Study Of Discomfort Experienced By Surgical Patients On Three Selected Postoperative Days, Lillian Barker Bartlett
Loma Linda University Electronic Theses, Dissertations & Projects
A descriptive survey was conducted to compare the discomfort experienced on three selected postoperative days to determine if there is one day identified by the patient as the most uncomfortable and to assess the symptoms of which he might complain. A checklist of twelve symptoms common to postsurgical patients was administered on the evenings of the second, third and fourth postoperative days by the researcher. Findings indicated that nineteen or 56 per cent of the thirty-four patients interviewed stated that the second day was most uncomfortable, nine or 27 per cent the third and six or 17 per cent the …
Factors Which Deterred Twenty-Three Selected Patients From Utilizing Public Health Nursing Services, Lora Wood Welch
Factors Which Deterred Twenty-Three Selected Patients From Utilizing Public Health Nursing Services, Lora Wood Welch
Loma Linda University Electronic Theses, Dissertations & Projects
A study was conducted to identify factors which deterred twenty-three selected epileptic patients from utilizing public health nursing services. The literature was reviewed in areas relating to factors which may contribute to or deter patients use of clinic or public health services.
The descriptive survey approach employing an interview guide was used. Data on the guide were classified in two areas: (1) personal characteristics and (2) participant responses. The participant responses were further categorized according to (1) perception of the public health department and public health nursing services, (2) perception of the needs of the epileptic patient and his parents, …
Properties Of Chlorophyll Derivatives Bonded To Polymers, Richard Grant Jensen
Properties Of Chlorophyll Derivatives Bonded To Polymers, Richard Grant Jensen
Theses and Dissertations
Two types of water-soluble complexes of chlorophyll a with organic polymers have been investigated: chlorophyll a coordinately bonded to poly 4-vinylpyridine and a chlorophyll derivative, Mg-chlorin e_6 phytyl methyl ester, covalently bonded to GANTREZ AN (poly (methyl vinyl ether/maleic anhydride) ). The first complex was observed upon dissolving chlorophyll a and poly 4-vinylpyridine in aqueous ethanol solutions. The Mg-chlorin e_6 diester-GANTREZ AN complex (chlorophyll a/polymer) was made by aminolysing the chlorophyll ring V with 1, 6-hexanediamine to give an intermediate product, Mg-chlorin e_6 -6-N-(6' -aminohexyl) carboxamide, phytyl methyl ester. This was attached to GANTREZ AN by linkage of the 6'-amine …
Thermodynamics Of Charge Transfer Complexes, Reed J. Jensen
Thermodynamics Of Charge Transfer Complexes, Reed J. Jensen
Theses and Dissertations
Charge transfer complexes were studied spectrophotometrically in the liquid state by a modified Benesi-Hildabrand method. TiCl_4 - Benzene and TiCl_4 - diphenyl ether solutions were found to form contact charge transfer complexes, that is complexes with very weak and non-directional interactions. The systems TiCl_4 - anisole and TiCl_4 - diethyl ether form complexes of the types AD and AD_2 where A stands for TiCl_4 and D stand s for the organic donor. The formation constants for the complexes were, for the TiCl_4 - anisole, K_1 = 0.077, K_2 = 0.01; and TiCl_4 - diethyl ether, K_1= 3.0, K_2 = 1.0. …
Rings With A Not Necessarily Transitive Order Relation, Lawrence Arnold Machtinger
Rings With A Not Necessarily Transitive Order Relation, Lawrence Arnold Machtinger
Retrospective Theses and Dissertations
The main objective of this paper is the study of rings with a relation which has all the properties of an order relation on a ring except, perhaps, for one: transitivity. Consequently, many of the results presented here are generalizations of well-known facts about transitively ordered rings; and most, but not all, of the conclusions of this paper are applicable to such rings.
Decision Problems, Lowell Anderson
Decision Problems, Lowell Anderson
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
From an intuitive point of view the notion of effective procedure consists of a set of rules or instructions that enables one, in a finite number of steps and in a purely mechanical way, to answer yes or no to any one of a given class of questions. This procedure requires no intelligence to carry out the instructions and, in fact, it is conceivable that some mechanical contrivance may be constructed to carry out these instructions. Should such an effective procedure exist, that answers either yes or no, then the group of problems in question is said to be effectively …
Ua77/1 Alumni Bulletin, Vol. 32, No. 2, Wku Alumni Association
Ua77/1 Alumni Bulletin, Vol. 32, No. 2, Wku Alumni Association
WKU Administration Documents
Alumni newsletter published by WKU. This issue has the following articles:
- President Kelly Thompson Announces Master Plan
- Western to Offer Graduate Degree Program in Engineering Physics
- Summer Session Slated to Open on June 14
- Robertson, Lee. From the Alumni Office
- Class of 1915
- Class of 1925
- Class of 1940
- Class of 1955
- Class of 1964
- Sports in Brief
- William Solly Becomes New Physical Education Head
- Graduate Assistantships Now Available
- James McKee Joins Education Department
- On the Calendar
- Commencement Day Activities
A Thermodynamic Study Of (1) Ligand Replacement Reactions And (2) The Interaction Of Hgcl[Subscript 2](Aq) With Hydroxide Ion, Ethylenediamine, Glycinate Ion, And Methylamine, Jerry Alvin Partridge
A Thermodynamic Study Of (1) Ligand Replacement Reactions And (2) The Interaction Of Hgcl[Subscript 2](Aq) With Hydroxide Ion, Ethylenediamine, Glycinate Ion, And Methylamine, Jerry Alvin Partridge
Theses and Dissertations
A method is reported for determining the species formed in solution by ligand replacement reactions. Reactions in dilute aqueous solution were studied in which the Cl^- on HgCl_2(aq) was replaced by hydroxide ion, ethylenediamine, glycinate ion, and methylamine. The species formed by the replacement reactions were established through computer analysis of pH titration data. Various reaction sequences were proposed for each system and log K values were calculated for each sequence. The selection of the correct reaction sequence for each system was based on the premise that only when the correct sequence is proposed will consistent log K values be …
The (He3,D) Reaction On The N=28 Nuclei., Dale D. Armstrong
The (He3,D) Reaction On The N=28 Nuclei., Dale D. Armstrong
Physics & Astronomy ETDs
A beam of 22-MeV He3 ions from the Los Alamos variable energy cyclotron was used to investigate the (He3,d) reaction on Ca48, v51, Cr52, and Fe54. A solid-state E-deltaE mass-identification detector system was used. The use of a summing preamplifier for perfoming the coherent addition of the E and 6E pulses allowed the energy resolution to be reduced to the inherent energy spread of the cyclotron beam, which is 100 to 120 keV. Levels or groups of levels were resolvable up to an excitation of 5 to 6 MeV for all the nuclei that were studied, and angular distributions were …
Hydrogenation Of 4-Methylcinnoline, William E. Maycock
Hydrogenation Of 4-Methylcinnoline, William E. Maycock
Theses and Dissertations
The rapid expansion of knowledge of cinnoline chemistry since 1941 has not included the hydrocinnolines. Not one catalytic hydrogenation of a fully aromatic cinnoline had been reported. This thesis is an effort to enlarge knowledge of this particular area of cinnoline chemistry. The work is a natural outgrowth of that done at Brigham Young University on decahydroquinoxaline, both the cis- and trans- isomers having been prepared and characterized. 4-Methylcinnoline, prepared by the method of Jacobs, et.al., was hydrogenated in neutral and acidic ethanolic solutions at 2000-3000 psig. hydrogen pressure and 100-266°. The catalysts used were 5% palladium on alumina, ruthenium …
The Intentionality Structure Of Complementarity, Patrick A. Heelan
The Intentionality Structure Of Complementarity, Patrick A. Heelan
Research Resources
In this article Heelan argues that the return to the concrete and empirical implied in Heisenberg's insight on the importance of observables in physics was not, however, in Heisenberg's case, accompanied by a thorough re-thinking of the rationalist presuppositions of classical physics. The effect on Bohr, however, was to lead him to a complete rejection of rationalism and to the adoption of the contrary extreme, empiricism. The profound – though largely implicit – cause of the disagreement between Bohr and Heisenberg as to the correct interpretation of quantum mechanics, was resolved in the sumnler of 1927, by the common acceptance …
Miocene Mammals And Central American Seaways, Frank C. Whitmore Jr., Robert H. Stewart
Miocene Mammals And Central American Seaways, Frank C. Whitmore Jr., Robert H. Stewart
United States Geological Survey: Staff Publications
The fossil mammal faunas of North and South America indicate that the two continents were separated from Paleocene or earlier time until the late Pliocene. Unfortunately our almost complete ignorance of the Tertiary land mammals of Central America, the geology of this large area, makes reconstruction of the Tertiary zoogeography of the region between the continents an exercise involving considerable speculation.
Available Water Supply Of The Las Vegas Ground-Water Basin Nevada, Glenn Thomas Malmberg
Available Water Supply Of The Las Vegas Ground-Water Basin Nevada, Glenn Thomas Malmberg
Publications (WR)
The Las Vegas ground-water basin as described in this report includes the southern part of Indian Spring Valley, Three Lakes Valley, the northern half of Ivanpah Valley, and Las Vegas Valley. These valleys in part are inferred to form a hydrologic unit that includes an area of about 3,000 square miles in the southern part of Clark County, Nev.
The valleys forming the Las Vegas ground-water basin are broad structural depressions surrounded by mountains. The climate of the region is arid, and precipitation in the basin lowlands rarely exceeds 5 inches per year. Drainage is interior except for occasional Hood …
Studies On The Conversion Of Indole Acetic Acid And Oxindole Acetic Acid By Hygrophorous Conicus, Barbara Ruth Patterson
Studies On The Conversion Of Indole Acetic Acid And Oxindole Acetic Acid By Hygrophorous Conicus, Barbara Ruth Patterson
Masters Theses
"The fungus, Hygrophorous conicus, produces the enzyme, indole acetic acid oxidase, when grown in the presence of indole acetic acid (IAA) or tryptamine. The IAA acts both as an inducer and a substrate for this intracellular enzyme. The product of the oxidation catalyzed by the IAA oxidase is oxindole acetic acid (OIAA). Since the IAA and OIAA absorb maximally at two different wavelengths the use of spectrophotometric analysis was possible for assaying for the IAA oxidase activity. Paper chromatography was used for qualitative identification of the IAA and OIAA. The rate of growth and the rate of formation of the …
Geology Of The Lamy-CañOncito Area, Santa Fe County, New Mexico, Robert S. Goolsby
Geology Of The Lamy-CañOncito Area, Santa Fe County, New Mexico, Robert S. Goolsby
Earth and Planetary Sciences ETDs
The area studied lies in the vicinity of Lamy and Canoncito in Santa Fe County, about 17 miles southeast of Santa Fe, New Mexico.
The rocks range in age from Precambrian through Quaternary, Precambrian rocks include dark schist and pink gneiss, with minor amounts of greenstone and quaritzite, Overlying the Precambrian rocks is a sequence of sandy limestone called the Basal Limestone, of Mississippian and possibly Devonian age. The Pennsylvanian System is represented by the Sandia formation and Madera Limestone, which are dominantly dark shale and fossiliferous limestone. The Sangre de Cristo and Yeso Formations, Glorieta Sandstone, San Andres Linestone, …
Geology Of The San Mateo Peak Area, Socorro County, New Mexico., James W. Furlow
Geology Of The San Mateo Peak Area, Socorro County, New Mexico., James W. Furlow
Earth and Planetary Sciences ETDs
The San Mateo Mountains of south-central New Mexico consist of an uplifted block of Tertiary volcanics 20 miles wide by 4 miles ling. The San Mateo uplift is one of the bounding uplifts along the western side of the Rio Grande depression.
The basement rock as exposed just east of the San Mateos is a Precambrian granite; it is overlain in order by the Cambrian Bliss formation, the Ordovician Sierrite Limestone, Cable canyon sandstone, and Upham Dolomite, the Pennsylvanian Magdalena Group, and the Permian Abo Formation. These sedimentary rocks are unconformably overlain by Tertiary volcanic rocks of the Lower volcanic …
Geology Of The Rayado Area, Colfax County, New Mexico, Richard W. Simms
Geology Of The Rayado Area, Colfax County, New Mexico, Richard W. Simms
Earth and Planetary Sciences ETDs
The Rayado area is 25 miles west of Springer, New Mexico, in the southeastern foothills of the Cimarron Mountains. The range is a northward-plunging anticline with a core of Precambrian crystalline rocks. The mountains are bordered on the west by a normal fault and on the east by the high-angle Fowler Pass thrust fault of Laramide age. Rocks of Permian through Upper Cretaceous age were turned upward along the fault forming a prominent north-south hogback through the western part of the area.
Spectrographic Study Of The Afterglow Of Mercury, Edward E. Stepp, Richard A. Anderson
Spectrographic Study Of The Afterglow Of Mercury, Edward E. Stepp, Richard A. Anderson
Physics Faculty Research & Creative Works
The short duration afterglow of 14 Hg lines was examined, at temperatures of 150°, 200°, 250°, and 300°F, in a cell that had been excited by an rf source. All of the lines exhibited a smooth exponential decay at the lowest temperature. At some temperature above 150°F, however, all of the lines, except the 2537- and 4079- Å lines, exhibited an enhancement of intensity in the time region between 50 and 100 µsec. At the highest temperature all of the lines originating from levels at an energy of 8.84 eV or above, except those originating from the 61D …
Lot Feeding Of Beef Cattle. 3. Facilities Required For A Feed Lot, W J O Wilkie
Lot Feeding Of Beef Cattle. 3. Facilities Required For A Feed Lot, W J O Wilkie
Journal of the Department of Agriculture, Western Australia, Series 4
MANY THINGS must be considered in planning a feed lot.
The site must be well chosen, fencing, gates and yards must be adequate for the cattle carried and feeding and watering facilities should be of a high standard.
Other things to consider are the provision of shelter and shade for the cattle and buildings for feed storage and other purposes.
Comparison Of Methods To Select A Probability Model, Howard Lyndal Colburn
Comparison Of Methods To Select A Probability Model, Howard Lyndal Colburn
Masters Theses
"A comparison is made between the estimates of the parameters in a gamma distribution obtained by the method of moments with those obtained by a numerical approximation to the maximum likelihood estimates. The estimates obtained by the numerical approximation had a smaller mean squared error from the true value than the estimates obtained by the method of moments. Modifications to tests of fit are made in order to develop methods to select a distribution from a set of possible distributions for a population with an unknown distribution. These selection methods are compared in their ability to make correct selections. Although …
Linear And Quadratic Programming With More Than One Objective Function, William John Lodholz
Linear And Quadratic Programming With More Than One Objective Function, William John Lodholz
Masters Theses
"A computational procedure is presented for determining optimal solutions to the linear and quadratic programming problem when there is more than one objective function subject to linear constraints. In general a unique solution does not exist and a set of "best" or "efficient" points is determined and presented in graphical or tabular form. To solve the mathematical programming problems the simplex method is used for linear objective functions and Wolfe's method is used for quadratic objective functions"--Abstract, page ii.
Petrology And Mineralogy Of The "Old Workings Area," El Salvador, Chile, Bertis James Vander Schaaff
Petrology And Mineralogy Of The "Old Workings Area," El Salvador, Chile, Bertis James Vander Schaaff
Masters Theses
"The 'Old Workings Area,' so called for its early mining by the Incas, is located 4 1/2 miles northeast of the El Salvador Porphyry copper deposit, the third largest copper producer in Chile. The area mapped in this study is shown to consist of rhyolite pebble conglomerate, two volcanic flows, andesite and rhyolite porphyry, and two intrusions. Quartz porphyry and tourmaline-bearing breccia. Petrographic study of surface and drill core rock samples confirms the field nomenclature used for the five rock types. All of the rock types are altered, but the quartz porphyry and andesite are the most intensely altered. Both …