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Articles 11101 - 11130 of 12097
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Transformations Of Tryptamine And Tryptophan By Basidiomycetes, Hsaio-Lung Cheng
Transformations Of Tryptamine And Tryptophan By Basidiomycetes, Hsaio-Lung Cheng
Masters Theses
"The product formed from tryptamine by Trichloloma nudum was identified as indoleacetic acid (IAA) and from tryptophan by Cantharellus cibrarius as indolelactic acid (ILA). The products were extracted from the spent media with organic solvents. Purification and identification of the crystalline transformation products were accomplished by means of paper chromatography, spectrophotometry and thin layer chromatography.
The conversion of tryptamine and tryptophan was also studied in cultures of Lencopaxillus paradoxus, Pluteus granularis and Pleuatus ostreatus. Only Pluteus granularis was found to transform tryptamine into IAA. Lencopaxillus paradoxus transformed tryptamine into oxindoleacetic acid (OIAA).
Paper chromatography proved to be useful …
A Study Of Certain Conservative Sets For Parameters In The Linear Statistical Model, Roger Alan Chapin
A Study Of Certain Conservative Sets For Parameters In The Linear Statistical Model, Roger Alan Chapin
Masters Theses
"In the case of the linear statistical model, it has been shown that under certain conditions the confidence intervals obtained by considering the parameters one at a time are conservative when used as a joint confidence region, using the product of confidences as the confidence. However, nothing had been known of how conservative they are. This research provides accurate estimates of the true confidence for these cases.
Also, it has not yet been proved that they are indeed conservative for all cases. It is thought that they are, and the results of this research support this conjecture"--Abstract, page ii.
Zinc And Copper Content Of Stream Sediment In South-Central Missouri, Shih-Cheang Cheng
Zinc And Copper Content Of Stream Sediment In South-Central Missouri, Shih-Cheang Cheng
Masters Theses
"Thirty samples of stream sediment from the North Fork River, Bryant Creek and related tributaries in south-central Missouri have been analyzed for cold-extractable copper, cold-extractable heavy metal, total copper and total zinc.
Cold-extractable copper varies from 0 to 10 ppm and averages less than 1 ppm; cold-extractable heavy metal varies from 3 to 30 ppm and averages 12 ppm; total copper varies from 50 to 200 ppm and averages 88 ppm; total zinc varies from 20 to 300 ppm and averages 86 ppm.
The pH of the stream water appears to have no affect on the metal content of the …
The Eccentric Orifice As A Flow Measuring Device In Small Diameter Pipes, James E. Casale
The Eccentric Orifice As A Flow Measuring Device In Small Diameter Pipes, James E. Casale
Masters Theses
"This thesis reports and evaluates the use of an eccentrically placed orifice as a flow measuring device in small pipe sizes. The orifice is placed in a concentric location and moved to increasingly eccentric locations until full eccentricity is reached. At full eccentricity the circumference of the orifice is tangent to the circumference of the pipe. The effects of increasing eccentricity are evaluated for four orifices...Flow coefficients for the orifices in different locations are plotted against Reynolds numbers. The eccentric orifice is a reliable, accurate flow measuring device for metering or controlling the flow of fluids. Design criteria can be …
A Graphical Method Of Estimating Heat Capacities Of Hydrocarbons, Pu-Ying Liu
A Graphical Method Of Estimating Heat Capacities Of Hydrocarbons, Pu-Ying Liu
Masters Theses
"Heat capacity arises because the individual particles comprising a substance are able to move and thus take up kinetic energy and usually also potential energy as the temperature rises. In many substances electrons do not absorb energy until very high temperatures are reached. Thus most heat capacity effects are interpreted in terms of the motion of the atoms neglecting electronic transitions. The total internal energy of a material is, therefore, equal to the sum of the energies due to translational and rotational motion of the molecules and to the vibrational motion of the atoms making up the molecules...The objective of …
A Study Of The Structural Rearrangements Accompanying Room Temperature Recovery Of High Purity Aluminum, Carlos Manuel Lago
A Study Of The Structural Rearrangements Accompanying Room Temperature Recovery Of High Purity Aluminum, Carlos Manuel Lago
Masters Theses
"X-ray methods (Laue back reflection and transmission) and etch pit studies were used in order to follow structural changes in the deformed metallic lattice during room temperature recovery. The accumulative evidence indicates that the deformed lattice undergoes subboundary movements and regrouping of fragments within a few days after stressing. On the basis of a superficial investigation, it was found that fast neutron bombardment increases the rate of room temperature recovery. Through the use of a new etchant, a finer substructure was revealed within the Lacombe subgrain. Glide strain values were determined for the series investigated, and a new approach was …
Thermal Degradation Of Poly (Methyl Methacrylate) In Solution In Various Solvents, Ya-Chih Chen
Thermal Degradation Of Poly (Methyl Methacrylate) In Solution In Various Solvents, Ya-Chih Chen
Masters Theses
"A study has been made of the thermal degradation of poly (methyl methacrylate) of different molecular weights in toluene, ethyl acetate and chloroform. Four poly (methyl methacrylate) samples having molecular weights of 2,210,000, 733,000, 320,000, and 43,00, respectively were studied in this investigation. The results indicated that the polymer having a molecular weight of 2,210,000 undergoes degradation while the low molecular weight polymers having molecular weights of 733,000, 320,000, 43,000 undergo reverse polymerization"--Abstract, page [ii].
A Study Of The Effect Of Surface Beveling On Silicon Rectifiers, Gary L. Voorhis
A Study Of The Effect Of Surface Beveling On Silicon Rectifiers, Gary L. Voorhis
Masters Theses
"The problem in this thesis is to experimentally obtain voltage vs distance data for different angles of bevel, to determine the optimum bevel angle on the basis of minimum surface electric field, and also to determine the location of the maximum surface electric field with respect to the p-n junction. Experimental equipment is constructed and results are graphically illustrated. It is concluded that in general the maximum surface electric field decreased as the bevel angle decreased, that neglecting practical considerations the optimum bevel angle was 3⁰, and that the maximum surface electric field occurred near, but not at the p-n …
Maximum Present Value Calculations With Digital Computers, James Boyd Robison
Maximum Present Value Calculations With Digital Computers, James Boyd Robison
Masters Theses
"This paper discusses maximum present value calculations for a mineral property using digital computers. A semi-quantitative mathematical model to optimize operating conditions is considered. The model is based on a modified cash flow analysis. Many variables affect the solution, and their effect upon present value is described. Selected data (mining rate, costs, reserves, metal sales price, and others) for a hypothetical open pit copper mine are used in a set of solutions for present value. The results are discussed in detail. It is concluded that: (1) Digital computer methods are rapid and useful, (2) Changes in the mining rate, average …
Drop Growth In A Supersaturated Vapor, Roger Buecher
Drop Growth In A Supersaturated Vapor, Roger Buecher
Masters Theses
"Using kinetic theory and the thermodynamics of phase transitions, a method is derived for finding the growth rate and temperature increase of a droplet in water vapor which has been supersaturated by the expansion of a cloud chamber. Calculations are performed for a specific numerical example and compared to other work in this field"--Abstract, page [2].
The Design And Construction Of A Shock Tube Facility, William Adolph Crede
The Design And Construction Of A Shock Tube Facility, William Adolph Crede
Masters Theses
"It is the object of this thesis to give an account of the considerations necessary to design, construct, and operate a shock tube facility.
The primary purpose of the facility was to provide a means to study high strength shock waves in physics, chemistry, and aerodynamic applications.
Preliminary designs were undertaken to determine the basic dimensions and related capabilities. Final design, construction and testing of the tube itself was performed by Nooter Corporation in St. Louis, Missouri. Preliminary designs agreed rather closely with final construction.
Experimental testing was confined to the successful operation of all the various components of the …
A Terrain Study Of The Bloodland Quadrangle, Pulaski County, Missouri, Lawrence E. Mullins
A Terrain Study Of The Bloodland Quadrangle, Pulaski County, Missouri, Lawrence E. Mullins
Masters Theses
"This study is an investigation of the environmental conditions which affect cross country movement for tracked military vehicles on a major portion of the Fort Leonard Wood Military Reservation.
The terrain has been mapped from the trafficability standpoint by an investigation of the geology, topography, pedology and restrictive vegetation characteristics of the Bloodland seven and one-half minute quadrangle. The terrain analysis was accomplished by a combination of map study, laboratory investigation, photo interpretation, and direct field study of representative soil and vegetation types. The conclusions of this analysis are presented in the form of a cross country movement map"--Abstract, page …
Investigation Of The Use Of Optics In The Analysis Of Structures, Jimmy D. Hahs
Investigation Of The Use Of Optics In The Analysis Of Structures, Jimmy D. Hahs
Masters Theses
"This study was made to determine the feasibility of the use of optics in the analysis of structures. Since the curvature of a beam due to a loading condition is a function of the moment, a measure of this curvature is a measurement of the moment.
This study used the relationship between object size and image size formed by a concave or convex reflective surface to determine the radius of curvature and the moment at the point.
Overhanging simply supported beams of plexiglass with concentrated loads at various positions were used to demonstrate the developed optical theory. Optical measurements were …
Mass Transfer In The Electrodialytic Desalination Of Brackish Water And A Correlation Of Experimental Data With Theory, James Shih-Jiann Yang
Mass Transfer In The Electrodialytic Desalination Of Brackish Water And A Correlation Of Experimental Data With Theory, James Shih-Jiann Yang
Masters Theses
"The object of this work is an experimental investigation into the possibility of obtaining an increase in mass transfer in the electrodialysis of brackish water by altering the physical character of the selective membrane, and a correlation of experimental mass transfer data with theory"--Introduction, page 1.
A Computer Approach To Transistor Circuit Design, Kwok Chee Hong
A Computer Approach To Transistor Circuit Design, Kwok Chee Hong
Masters Theses
"The design of amplifiers is usually approached through experimental study. This thesis proposes a mathematical approach, using a digital computer to predict the performance of an active transistor circuit (a frequency equalizer circuit to compensate for the RIAA recording frequency characteristics) prior to the actual construction of the physical system. The simple but powerful computer analysis method will be based upon the nodal equations of the complete circuit. The primary aim is to design a circuit which would give a desired frequency-gain characteristic. The complete set of simultaneous complex nodal equations describing the circuit operation is then written. Based on …
The Effect Of Carbonate Karst Terrain On Water Quality, Robert Russell Kilgo
The Effect Of Carbonate Karst Terrain On Water Quality, Robert Russell Kilgo
Masters Theses
"The ever increasing use of water and unabated pollution of streams have made necessary increased research efforts into the quality and quantity of the available national water resources. Karst terrain is prevalent in several sections of the United States, however, little work has been done on the effect of this topography on water quality.
The purpose of this investigation was to determine the effect of carbonate karst terrain on the quality of water. The Meramec spring area, east of Rolla, Missouri, was selected for study. This area was underlain with dolomite formations and contains both karst and non-karst drainage basins …
The Elastic And Anelastic Constants Of A Synthetic Fluor-Mica Formed By Glass-Ceramic Fabrication Techniques, John H. Ainsworth
The Elastic And Anelastic Constants Of A Synthetic Fluor-Mica Formed By Glass-Ceramic Fabrication Techniques, John H. Ainsworth
Masters Theses
"A tetrasilicic fluor mica, K2Mg5Si8O20F4, was synthesized using glass forming techniques. Density changes, weight losses, and shrinkage, as well as elastic and anelastic properties, were measured on bars heat-treated at selected temperatures between 500°C and 1150°C to determine the characteristics of this material. Phase changes were followed by determining thermal expansion, logarithmic decrement, and modulus of elasticity from room temperature to 800°C.
It was found that the elastic and anelastic constants decreased gradually with heat treatments from 600°C to 1000°C. This indicated progressively increased structural ordering. Heat treatments above 1000°C …
An X-Ray Study Of The Lead Zirconate-Bismuth Ferrate System, Pen-Chu Chou
An X-Ray Study Of The Lead Zirconate-Bismuth Ferrate System, Pen-Chu Chou
Masters Theses
"The lead zirconate-bismuth ferrate system was studied employing x-ray and microscopic analysis. Samples were prepared by sintering stoichiometric mixtures of the corresponding oxides followed by air quenching. The results of the analyses show the system to be probably solid solutions over the entire compositional range, although small amounts of other phases are present in some regions.
X-ray data indicate a multiple cell, orthorhombic phase, to exist over the range 100-30 mole percent PbZrO₃ . From 100-82 mole percent PbZrO₃ , the addition of BiFeO₃ reduces the distortion of the phase such that a nearly cubic x-ray pattern is obtained at …
The Influence Of Cation Exchange And Electrolyte Concentrations Upon The Atterberg Limits, Kent J. Schwieger
The Influence Of Cation Exchange And Electrolyte Concentrations Upon The Atterberg Limits, Kent J. Schwieger
Masters Theses
"The object of this investigation is to correlate relationships between cation exchange capacity, clay content, and type and concentration of the exchangeable cations upon the Atterberg limits of a soil. Synthetic soils consisting of loessial silt and either an illitic natural deposit, bentonite, ball clay, or kaolin clay were used.
As the percent clay fraction was increased the cation exchange capacity, liquid and plastic limits and plasticity index increased linearly in the clay range. Results also suggested a linear relationship between the liquid and plastic limits and the cation exchange capacity of soils of one hundred percent clay fraction"--Abstract, page …
Infinite Beams On An Elastic Foundation, Shi-Peing Chang
Infinite Beams On An Elastic Foundation, Shi-Peing Chang
Masters Theses
"In this paper a partial differential equation for the analysis of beams resting on an elastic foundation under dynamic load is presented. A solution for this equation is derived, and solutions for various boundary conditions of infinite beams resting on an elastic foundation are discussed. The application of the equation is demonstrated by an example of a moving load traveling along an infinite beam"--Abstract, page ii.
Matching Of A Horn Antenna To Its Dense Surrounding Media By The Use Of Artificial Dielectric Methods, Paul Arthur Ray
Matching Of A Horn Antenna To Its Dense Surrounding Media By The Use Of Artificial Dielectric Methods, Paul Arthur Ray
Masters Theses
"The purpose of this thesis is to design an artificial dielectric slug to match a horn in a media such as water and to discuss a method of determining experimentally its dielectric properties. The design is based on known artificial dielectric methods. The method of determining the dielectric properties is by microwave waveguide reflection techniques. This thesis deals with the theoretical aspects and suggests an experimental method of determining the practicability of such a matching method"--Abstract, page ii.
Field Permeability Determination Of Partially Saturated Fine Grained Soil, Edward G. Rapp
Field Permeability Determination Of Partially Saturated Fine Grained Soil, Edward G. Rapp
Masters Theses
"The determination of water permeability through a soil is necessary to estimate seepage losses from small reservoirs. At the present time, the methods available to conduct this determination in partially saturated fine grained soils are expensive and in most cases not commensurate with the cost or importance of the individual structure. This investigation was conducted to evaluate the use of a proposed, potentially inexpensive field procedure in this situation. A modified borehole apparatus was utilized in field tests to determine the permeability of a partially saturated soil deposit in place. Undisturbed samples from the same location were tested in the …
Effects Of Internal Pressure Upon The Buckling Of Thin Circular Cylindrical Shells Under Axial Compression, Leroy E. Thompson
Effects Of Internal Pressure Upon The Buckling Of Thin Circular Cylindrical Shells Under Axial Compression, Leroy E. Thompson
Masters Theses
"An experimental investigation was made of the effects of internal pressure upon the buckling of thin circular cylindrical shells under axial compression. A comparison was made of the experimental and theoretical results; the latter were derived from the large-deflection theory. Results showed that the internal pressure had an appreciable strengthening effect upon the buckling of the cylindrical shell. The comparison showed that the experimental results were lower than the theoretical results for a given internal pressure. The discrepancy between the results can be expected since there were factors not included in the theory: imperfections, end conditions, lengths, and material irregularities"--Abstract, …
A Photoelastic Study Of The Effect Of Certain Geometric Variables On The Plane Stress Distribution In An Electrical Insulator Body, Richard L. Pendleton
A Photoelastic Study Of The Effect Of Certain Geometric Variables On The Plane Stress Distribution In An Electrical Insulator Body, Richard L. Pendleton
Masters Theses
"Photoelastic models were used to indicate stress patterns in various geometrically designed shapes. Each model represented a two-dimensional cross-section of the interior portion of an axially symmetrical porcelain electrical insulator. Five different loading pins were combined with three loading heads to produce eleven models. The maximum stress in each model was determined using a photoelastic method of stress analysis. An attempt was made to select the best structural design to be used in an electrical insulator. The test results indicate that the most desirable stress distribution is obtained using a single step loading pin and that the loading head angle …
Equivalent Circuit Of Unsymmetrical Inductance Diode Using Linvill Lumped Model, Donald Lawrence Willyard
Equivalent Circuit Of Unsymmetrical Inductance Diode Using Linvill Lumped Model, Donald Lawrence Willyard
Masters Theses
"Integrated circuit techniques and applications are rapidly changing the electronics industry. A problem common to both state-of-the-art approaches to integrated circuit fabrication is that of miniaturizing and integrating inductors. It is found that, for a certain range of injection current levels, certain unsymmetrically doped junction diodes have an inductive small-signal impedance. This thesis discusses the theory of inductance diodes and applies finite difference equations and the Linvill lumped model to the differential equations that describe their carrier flow processes. The static I-V characteristic and the small-signal equivalent circuit at high injection densities are derived. The elements (R,L,C) of this equivalent …
An Investigation Of Continuous Prestressed Concrete Structures, Ping-Chi Mao
An Investigation Of Continuous Prestressed Concrete Structures, Ping-Chi Mao
Masters Theses
"This thesis presents an analysis of the behavior of continuous prestressed concrete structures. From this analysis the governing equations for various types of geometry for prestressing cables are derived. The calculation of fixed-end moments due to the prestressing force using the equations derived is quite cumbersome, however, in order to simplify the calculations, design charts are developed. A cable with reverse curvature is analyzed using the design charts. It is shown that the fixed-end moments calculated by neglecting the effect of reverse curvature differ significantly from the fixed-end moments calculated by considering this effect. Hence the effect of reverse curvature …
The Design And Construction Of An Instrument For Calibrating Accelerometers, Richard Rabenau
The Design And Construction Of An Instrument For Calibrating Accelerometers, Richard Rabenau
Masters Theses
"The purpose of this work was to design and construct a facility to calibrate accelerometers. A ceramic piezoelectric shaker and modified Michelson interferometer together with necessary electronic equipment were used. The system produced accurate and stable acceleration at five discrete points from 1,000 to 5,000 cycles per second. the maximum calibration levels were approximately 50 g's"--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 …
A Circularly Polarized Corner Reflector Antenna, Walter Ronald Koenig
A Circularly Polarized Corner Reflector Antenna, Walter Ronald Koenig
Masters Theses
"Image theory is used to develop the far field and polarization equations for a ninety degree corner reflector antenna. These equations are in terms of spherical coordinates, the length of the dipole element, the distance of the dipole from the corner of the reflector, and the angle of tilt of the dipole element with the apex of the corner. The equations are simplified to give the far fields in the vertical and horizontal planes for the special case of a half-wavelength dipole. An expression to calculate the distance of the dipole from the corner necessary to give circular polarization broadside …
The Prediction Of Mix Design Properties For Dense Graded Bituminous Mixtures, Robert Ernest Weeks
The Prediction Of Mix Design Properties For Dense Graded Bituminous Mixtures, Robert Ernest Weeks
Masters Theses
"The purpose of this investigation was to ascertain the feasibility of interpolating values of the physical properties of a dense graded bituminous mix between known values. Also the effects of limestone mineral filler on the properties of a dense graded mix are evaluated. The variables in this study were mineral filler and asphalt cement. Control mixes were established at 2, 6 and 10 percent mineral filler and experimental mixes were prepared at 4 and 8 percent filler. The aggregate consisted of limestone and was mixed with an asphalt cement of 85-100 grade penetration. Al mixes were tested by the Marshall …