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Articles 288211 - 288240 of 292661
Full-Text Articles in Physical Sciences and Mathematics
Influence Of Various Factors On Aggregation Of Peorian Loess By Microorganisms, T. M. Mccalla, Francis A. Haskins, E. F. Frolik
Influence Of Various Factors On Aggregation Of Peorian Loess By Microorganisms, T. M. Mccalla, Francis A. Haskins, E. F. Frolik
Department of Agronomy and Horticulture: Faculty Publications
Soil structure is important in the attainment of adequate aeration for the aerobic microorganisms whose activities maintain such higher plant nutrients as sulfur, phosphorus, and nitrogen in a highly oxidized and thus readily available state. Good soil structure is also necessary for soil and water conservation, Under Nebraska conditions microorganisms and their decomposition products constitute a major source of soil-aggregating agents. The decomposition of crop residues and plant roots is important in the nutrition of these aggregating microorganisms. Other microorganisms, however, also utilize crop residues and plant roots, and they may decompose the aggregating agents as well, so that the …
Test 613: Case 311 Gasoline, Nebraska Tractor Test Lab
Test 613: Case 311 Gasoline, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT:
TEST A: The manufacturer's representative operates the tractor for a minimum of 12 hours using light to heavy drawbar loads in each gear.
This serves as a period for limber up, general observation and adjustments. Adjustments that are permissible include valve tappet clearance, breaker, point gap, spark plug gaps, clutch and others of a similar nature. No new parts or accessories can be installed without having mention made of it in the report. No data' are recorded during this preliminary run except the time that the engine is operated.
BELT HORSEPOWER TESTS
TEST B: The throttle …
Test 632: John Deere 830 Diesel, Nebraska Tractor Test Lab
Test 632: John Deere 830 Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
No abstract provided.
Investigations Of The Effects On Oyster Culture Of The Dredging For The Hampton Roads Bridge-Tunnel : An Investigation Conducted By The Virginia Fisheries Laboratory For The Virginia State Department Of Highways, Jay D. Able, Dexter S. Haven, John L. Mchugh
Investigations Of The Effects On Oyster Culture Of The Dredging For The Hampton Roads Bridge-Tunnel : An Investigation Conducted By The Virginia Fisheries Laboratory For The Virginia State Department Of Highways, Jay D. Able, Dexter S. Haven, John L. Mchugh
Reports
No abstract provided.
The Urea Adducts Of The Constituents Of California Montan Wax, Alan Howard Vanderbilt
The Urea Adducts Of The Constituents Of California Montan Wax, Alan Howard Vanderbilt
University of the Pacific Theses and Dissertations
Interest in the chemical constitution of montan wax began with the work of Von Boyen, who in 1901 showed montanic acid to be a constituent of the wax. In the years that followed the literature has been rich with respect to investigations of montan wax. Most of the literature concerns itself with the technology of the wax, its uses, methods of refining and purification. Much has also been written on its chemical make-up.
It was the purpose of this research to explore the possibility of forming urea adducts of the normal components of montan wax, and to investigate the properties …
Preparation Of Thiochalcone From Thioacetophenone, Thomas Joseph Reilly
Preparation Of Thiochalcone From Thioacetophenone, Thomas Joseph Reilly
University of the Pacific Theses and Dissertations
This thesis covers the practical research done on the condensation of thioacetophenone with benzaldehyde and the library research covers the chemistry of thioketones and the thioflavanones. Most of the thioketones have been made by dissolving a ketone in ethanol, usually absolute although 95 percent was also used, saturating the solution with anhydrous hydrogen chloride at ice temperature, then admitting hydrogen sulfide for several hours. This method was first used by Fromm and Baumann when they made thioacetophenone from acetophenone. David Shirley also gives theis process in his book “Preparation of Organic Intermediates” published by Wiley and Sons in New York. …
Geology Of The Southern Half Of The Millerstown, Pennsylvania 15 Minute Topographic Quadrangle, George Calvert Robinson
Geology Of The Southern Half Of The Millerstown, Pennsylvania 15 Minute Topographic Quadrangle, George Calvert Robinson
Graduate Theses, Dissertations, and Problem Reports
A detailed investigation of the geology of the southern one-half of the Millerstown, Pennsylvania 15 Minute Topographic Quandrangle was conducted during 1956-1957. This report of the work contains a description of the Silurian, Devonian, and Mississippian formations which crop out in the area. The complex folding and faulting of the sediments is outlined in a section on structural geology. A number of anticlines and synclines, not previously mapped, are described.
A geologic map and two structural cross sections with a scale of 1:24000 are included to illustrate the features described. This is the first geologic map of the area on …
Log Of Test Holes Frenchman Creek Basin Nebraska, C. F. Creech
Log Of Test Holes Frenchman Creek Basin Nebraska, C. F. Creech
Conservation and Survey Division
No abstract provided.
Northeastern Cherry And Western Keya Paha County Preliminary Ground Water Study 1957 (Gm-26): Reed, E.C. Conservation And Survey Division , Size 8.5" X 11"., E.C. Reed
Conservation and Survey Division
No abstract provided.
Thermal Reaction Of Hydrogen And Oxygen In Small Bore Tubes, Shib Charan Chattoraj
Thermal Reaction Of Hydrogen And Oxygen In Small Bore Tubes, Shib Charan Chattoraj
Theses and Dissertations
The thermal reaction of hydrogen and oxygen has been investigated from the standpoint of the important intermediate hydrogen peroxide in the region between 620-720 degrees centigrade in small bore Pyrex and steel tubes. The minimum explosion-temperatures with different flow rates and compositions of the mixture have been determined. They have been found to vary with the composition and flow rate of the mixture. The minimum explosion temperature is also found to vary with the condition of the reaction tube surface. The yield of hydrogen peroxide has been determined as a function of temperature, contact time, composition of feed stream, and …
A Geological Study Of The Irvine Ranch Area, Johnson And Campbell Counties, Wyoming, Gale E. Butterfield
A Geological Study Of The Irvine Ranch Area, Johnson And Campbell Counties, Wyoming, Gale E. Butterfield
Masters Theses
"The discovery of uranium in the Powder River Basin, Wyoming, by the U. S. Geological Survey in 1952 has lead to an extensive exploration program throughout the region by both private and governmental agencies. This report is a geological study of an area in the southwestern part of the basin.
Geological and radiometric mapping carried out as a part of this report indicated several areas of uranium occurrence. Some of these occurrences warrant tests by drilling.
Mineralogical and petrographic study has shown the principal uranium minerals to be carnotite and metatyuyamunite. The mineralization occurs in arkosic sandstones. Assays of the …
The Phosphoria Formation Of The Northeastern Big Horn Basin, Wyoming, William A. Beatty
The Phosphoria Formation Of The Northeastern Big Horn Basin, Wyoming, William A. Beatty
Masters Theses
"Purpose and Scope. — The Phosphoria formation of the northern Rocky Mountains of the United States has received considerable attention from geologists because of its important reserves of phosphate and petroleum. In the Big Horn Basin of Wyoming, however, still more work is needed to compile the information necessary for a complete understanding of the facies changes exhibited by this formation.
The purpose of this paper is two-fold: first to present a description of the lithology and the paleontology of the Phosphoria formation in the northeast part of the Big Horn Basin, and secondly to show the stratigraphic relationship of …
A Probe For Measuring Ultrasonic Pressures, Robert F. Rohrer
A Probe For Measuring Ultrasonic Pressures, Robert F. Rohrer
Masters Theses
"In the study of acoustics, the term ultrasonics is defined as those wave motions that have frequencies greater than about 20,000 cycles per second. The characteristics of a sound wave at any point in a medium can be regarded as completely defined when the amplitude, frequency, and phase of its Fourier components are known.
Sound measurements at their best are difficult. In the last few years sensitive linear microphones and electronic amplifiers have become available. Still, there are two difficulties of prime importance with their use in a sound field. First, there is the precise, absolute calibration of the equipment …
The Length And Age Composition Of Spot, Leiostomus Xanthurus, In The Pound Net Fishery Of Lower Chesapeake Bay, Anthony Louis Pacheco
The Length And Age Composition Of Spot, Leiostomus Xanthurus, In The Pound Net Fishery Of Lower Chesapeake Bay, Anthony Louis Pacheco
Dissertations, Theses, and Masters Projects
No abstract provided.
Ecological And Epidemiological Studies Of Nematopsis Ostrearum, A Sporozoan Parasite Of The Oyster Crassostrea Virginica, In Lower Chesapeake Bay And Its Tributaries, Sung Yen Feng
Dissertations, Theses, and Masters Projects
No abstract provided.
Transference Numbers Of Concentrated Manganous Chloride Solutions, Marshall L. Severson
Transference Numbers Of Concentrated Manganous Chloride Solutions, Marshall L. Severson
Masters Theses
"Electrolytic conduction differs from metallic conduction only in the nature of the carrier of the current. In the case of metallic conduction the carrier is electrons. The passage of an electric current through an electrolyte occurs only by the movement of ions of opposite charge moving in opposite directions under an applied potential. The current carried by a particular ionic species is a direct function of the concentration, the charge on the ion, and the ionic mobility. A transference number is the fraction of the total current a given ion carries in a particular electrolyte undergoing electrolysis. The sum of …
Detection Of Low Energy Positive Ions By Scintillation Methods, Graydon J. Hanson
Detection Of Low Energy Positive Ions By Scintillation Methods, Graydon J. Hanson
Masters Theses
"This thesis deals with the feasibility of efficiently detecting low energy positive ions, those with energies of less than several hundred electron volts, using phosphors.
The scintillation technique, first used visually and greatly improved in the last ten years by the use of a photomultiplier tube, has greatly advanced detection in high energy fields. The photomultiplier is capable of delivering milliampere pulses of current of short duration and these can be registered directly by the many electronic devices currently in use.
Extensive work has been done with phosphors which scintillate under which energy bombardment, due in part to their wide …
Some Thermodynamic And Structural Properties Of A Linear Chain Of Atoms, And Extension Of The Model To Two- And Three-Dimensional Cases, Hari Gopal Mukerjee
Some Thermodynamic And Structural Properties Of A Linear Chain Of Atoms, And Extension Of The Model To Two- And Three-Dimensional Cases, Hari Gopal Mukerjee
Masters Theses
"An attempt has been made in the present work to derive some thermodynamic and structural properties of a linear chain of atoms (under somewhat idealized conditions) moving in the fields of nearest neighbours and assuming a parabolic well in the interaction of pairs within the range of relative movements. The equation of state and other formulas derived are applicable only to the linear model which could be considered as a simplified form of one-dimensional crystals in the form of chain-like molecules of rubber-like substances. An attempt has also been made to extend the model to two- and three-dimensional cases"--Introduction, page …
Internal Friction In Manganese Copper Alloys, William Paul Dixon
Internal Friction In Manganese Copper Alloys, William Paul Dixon
Masters Theses
"The study of the physical properties of the manganese-copper alloys is an intriguing one. These alloys show promise of usefulness in instances in which high internal friction is needed to reduce the noise and vibrational stresses at resonant frequencies of a part of a machine. The purpose of this study has been to learn more about the internal friction of manganese-copper alloys as a function of temperature, stress amplitude, frequency, time, and past history of the specimen. From this information the mechanism for absorption of vibrational energy is proposed, or at least some progress has been made toward its determination. …
Gastropoda From The Pierre Shale (Upper Cretaceous) Of Emmons County, South-Central North Dakota, Alan M. Cvancara
Gastropoda From The Pierre Shale (Upper Cretaceous) Of Emmons County, South-Central North Dakota, Alan M. Cvancara
Theses and Dissertations
Fossil gastropods were studied from the upper part of the Pierre shale (Upper Cretaceous) in Emmons County, south-central North Dakota. This primary purpose of this study was to figure all gastropods found and bring the nomenclature of up to date. Secondly, an attempt was made to determine whether these fossil gastropods could be used in defining the contact between the Pierre shale and overlying Fox Hills sandstone.
Little paleontological work has been done on Pierre gastropods in North Dakota. Identification previously made seem to have been done somewhat hurriedly from Meek (1876) with little regard to modernizing the nomenclature.
These …
A Study Of Methods Of Preparation Of Phthalaldehyde, Harold Leon Chambers
A Study Of Methods Of Preparation Of Phthalaldehyde, Harold Leon Chambers
University of the Pacific Theses and Dissertations
Considerable work has been done in recent years on the general field centering around the chalcones, flavones, and anthocyanidins. Members of the three classes of compounds exist as natural products and occur widely as coloring matter in flowers and plant saps.
An attempt has been made to work out a new method for the preparation of phthalaldehyde. Two lines of research have been followed, neither of which produced the desired compound.
The first method, low-pressure hydrogenation of dibutylphthalate over Raney nickel catalyst has supported the contention that the principal product of the hydrogenation of aromatic esters over Raney nickel arises …
A 120 Megacycle Self-Contained High-Frequency Titrimeter, John Kyle Clinkscales Jr.
A 120 Megacycle Self-Contained High-Frequency Titrimeter, John Kyle Clinkscales Jr.
University of the Pacific Theses and Dissertations
The analytical chemist is ever eager to improve and expedite present analytical methods.. In the past ten years considerable interest .has been elicited in the field of high frequency oscillators and their application to analytical chemistry. One of the main reasons for this interest is the uniqueness of the apparatus. No direct contact is made between the measuring instrument and the solution. Credit tor this interest must be given primarily to Jensen and Parrack of Texas A & M University. Their article in 1946 described a simple tuned plate-tuned grid electronic oscillator, operating in the high frequency range. A solution …
The Synthesis Of 7-Methyl-3,4-Benzpyrene, 6,7-Dimethyl-3,4-Benzpyrene, 10-Methyl-3,4-Benzpyrene And 7,10-Dimethyl-3,4-Benzpyrene, Joseph Leonard Comp Jr.
The Synthesis Of 7-Methyl-3,4-Benzpyrene, 6,7-Dimethyl-3,4-Benzpyrene, 10-Methyl-3,4-Benzpyrene And 7,10-Dimethyl-3,4-Benzpyrene, Joseph Leonard Comp Jr.
Chemistry and Chemical Biology ETDs
Interest in carcinogenic compounds began to develop when a form of cancer was found occurring in chimney sweeps in 1775. Skin cancer was found among workers in tar industries in 1875, and in 1887 workers in cotton spinning industries were known to have cancer which was attributed to contact with lubricating oils. Girls who painted the luminous dials of watches contracted cancer from exposure to the radioactive paint, and men who worked with B-naphthylamine developed bladder cancer. Many other cases of occupational cancer were reported before a systematic study of carcinogenic substances was begun. Early attempts to produce cancer in …
A Comparison Of The Accuracy Of Finite Difference Methods And Variational Methods In The Numerical Solution Of Partial Differential Equations, Robert F. Brodsky
A Comparison Of The Accuracy Of Finite Difference Methods And Variational Methods In The Numerical Solution Of Partial Differential Equations, Robert F. Brodsky
Mathematics & Statistics ETDs
The purpose of this thesis is to investigate some of the numerical methods available to solve partial differential equations intractable to analytic solutions with a view towards: 1. Indicating where particular methods appear most applicable, from the standpoints of accuracy, easy of solution, minimum expenditure of effort; and 2. Indicating the accuracy to be expected in the use of two of the more powerful methods investigated as applied to a problem of elasticity.
Range Liverstock Nutrition And Its Importance In The Intermountain Region, C. Wayne Cook
Range Liverstock Nutrition And Its Importance In The Intermountain Region, C. Wayne Cook
Faculty Honor Lectures
It has been estimated that about 728 million acres or about 76 percent of the entire land area in the West is used for grazing (Stoddard and Smith 1956). In Utah about 93 percent of the land area or 48,900,000 acres is considered range land (Reuss and Blanch 1951). Although some of this range land is forested, a large area of it can be used only for grazing. Therefore, range livestock production is an important segment of western agriculture.
Before 19'00 most of the animals in the West grazed on the range all year. However, irrigation crop production has expanded …
Correlation Between Grades In Engineering Physics And Performance In Engineering Curricula, Donald Hoyt, Louis D. Ellsworth, Robert Katz
Correlation Between Grades In Engineering Physics And Performance In Engineering Curricula, Donald Hoyt, Louis D. Ellsworth, Robert Katz
Robert Katz Publications
A survey of grades in Engineering Physics I at Kansas State College showed that the inner structure of the course was highly consistent. The correlation coefficient between the average of the first three tests and the final grade was about 0.88. More significantly, valuable prognostic data could be obtained from the final grade in the course. The correlation coefficient between the Engineering Physics I grade and the final grade point average of students who completed the course was about 0.83. Only 21% of the students initially failing the course successfully completed an engineering degree, while about 75% of the A, …
On The Equivalence Of The Ring, Lattice, And Semigroup Of Continuous Functions, Melvin Henriksen
On The Equivalence Of The Ring, Lattice, And Semigroup Of Continuous Functions, Melvin Henriksen
All HMC Faculty Publications and Research
A large number of papers have been published that are devoted to showing that certain algebraic objects obtained by defining operations on the set of all continuous real-valued functions on a suitably restricted topological space determine the space. We mention but a few of them in this article.
A Laboratory Study Of The Beech Granite Plagioclase, Joseph Taylor Carlisle
A Laboratory Study Of The Beech Granite Plagioclase, Joseph Taylor Carlisle
Masters Theses
Introduction: In northeast Tennessee a complex basement of Pre-Cambrian crystalline rocks either unconformably underlies the oldest Cambrian sediments, or bears a faulted relationship to them. The complexity of these rocks is, indeed, so great that much doubt exists as to the origin and even the nature of their component rock units. Keith (1907, p. 3) subdivided these rocks into two large units: (1) the Cranberry "granite," in this region a highly contorted gneiss of complex lithology, and (2) the Beech granite, a rather porphyritic, generally coarse-grained granite which he considered to have been considerably squeezed and mashed. Of these Keith …
Test 606: John Deere 720/730 All-Fuel, Nebraska Tractor Test Lab
Test 606: John Deere 720/730 All-Fuel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT: John Deere 720/730 All-Fuel TEST A: The manufacturer's representative operates the tractor for a minimum of 12 hours using light to heavy drawbar loads in each gear. This serves as a period for limber up, general observation and adjustments. Adjustments that are permissible include valve tappet clearance, breaker ,point gap, spark plug gaps, clutch and others of a similar nature. No new parts or accessories can be installed without having mention made of it in the report. No data' are recorded during this preliminary run except the time that the engine is operated. BELT HORSEPOWER TESTS …
Test 605: John Deere 720/730, Nebraska Tractor Test Lab
Test 605: John Deere 720/730, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT: John Deere 720/730 TEST A: The manufacturer's representative operates the tractor for a minimum of 12 hours using light to heavy drawbar loads in each gear. This serves as a period for limber up, general observation and adjustments. Adjustments that are permissible include valve tappet clearance, breaker ,point gap, spark plug gaps, clutch and others of a similar nature. No new parts or accessories can be installed without having mention made of it in the report. No data' are recorded during this preliminary run except the time that the engine is operated. BELT HORSEPOWER TESTS TEST …