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Articles 3781 - 3797 of 3797
Full-Text Articles in Physical Sciences and Mathematics
"Remarks On The Motion Picture No Blade Of Grass", Cornel Wilde
"Remarks On The Motion Picture No Blade Of Grass", Cornel Wilde
Special Collections: Oregon Public Speakers
No abstract provided.
Electron Optical Study Of A Secondary Electron Multiplier, Chang Min Shen
Electron Optical Study Of A Secondary Electron Multiplier, Chang Min Shen
Dissertations and Theses
Electron orbital theory was applied to the design of the geometrical structure of an electron multiplier for an image intensifier. A special structure satisfying production requirements was studied. Electron optical calculations consisted of determining the potential distribution and tracing the electron trajectories. Liebmann's procedure was used to solve Laplace's equation with constant potentials on the multiplier electrodes as boundary conditions. The trajectories were determined by solving the equation of motion in an electrostatic field using a Runge-Kutta procedure. The initial conditions for the trajectories were the initial energies, initial positions, and the initial directions of the secondary electrons. The plotted …
Distribution Of The Sum Of Independent Unity-Truncated Logarithmic Series Variables, Russell James Wayland
Distribution Of The Sum Of Independent Unity-Truncated Logarithmic Series Variables, Russell James Wayland
Dissertations and Theses
Let X1, X2, ..., Xn be n independent and identically distributed random variables having the unity-truncated logarithmic series distribution with probability function given by f(x;θ) = αθX/x x ε T where α = [-log(1-θ) - θ]-1, 0 < θ < 1, and T = {2,3,...,∞}. Define their sum as Z = X1 + X2 + ... + Xn.
We derive here the distribution of Z, denoted by p(z;n,θ), using the inversion formula for characteristic functions, in an explicit form in terms of a linear combination of Stirling numbers of the first kind. A recurrence relation for the probability function p(z;n,θ) is obtained …
The Chemistry Of Trifluorothiolacetic Acid, Patricia Diane Weeks
The Chemistry Of Trifluorothiolacetic Acid, Patricia Diane Weeks
Dissertations and Theses
Addition reactions of perfluorothiolacetic acid (TFTAA) with organic and inorganic substrates were studied and six new compounds containing the trifluoroacetyl group have been prepared. Two types of reactions were observed, free radical and nucleophilic addition. Under the influence of ultraviolet light, TFTAA (CF₃COSH) adds to olefins to form 1:1 adducts. The CF₃COS• radical appears to be the adding species. Three new olefin adducts were prepared: CF₃COSCFHCF₂H, CF₃COSCH₂CF₂H, and CF₃COSCH₂CFH₂. In addition, this was found to be a new way to prepare CF₃COSCH₂CH₃, which had been previously prepared by another route. Physical constants, analytical data, infrared, ultraviolet, nmr and mass spectra …
Hot Electron Injection Into Liquid Argon From A Tunnel Cathode, Pavel Smejtek, David G. Onn, M. Silver, P. Kumbhare
Hot Electron Injection Into Liquid Argon From A Tunnel Cathode, Pavel Smejtek, David G. Onn, M. Silver, P. Kumbhare
Physics Faculty Publications and Presentations
Hot electrons from a tunnel cathode have been injected into liquid argon (99.998% pure) at 87°K. The current vs voltage characteristics indicate that the injected hot electrons thermalize very slowly, losing their energy only by elastic scattering processes and finally by capture by the dilute impurities. The deduced thermalization time and distance are very long compared with that in helium, where bubble formation is responsible for energy loss.
Investigation Of The Alpha-Sub-Gamma Phase In Alnico 6, Cortez Samuel
Investigation Of The Alpha-Sub-Gamma Phase In Alnico 6, Cortez Samuel
Dissertations and Theses
The purpose of this research project was to study the αᵧ phase in Alnico 6. Other phases were studies for comparison. Also the effect of an applied magnetic field on the formation of the αᵧ phase was investigated.
Three single crystals of Alnico 6 were heat treated for one hour—one at 1250°C, one at 1000°C, and one at 800°C—and water-quenched. The microstructure of each sample was observed with the optical microscope, and X-ray diffraction patterns were taken to determine the crystal structure of the phases present.
Several single crystal samples of Alnico 6 were heat treated at 1000°C and furnace-cooled. …
Cyclization Studies Involving The Synthesis Of 5-Substituted-1-Naphthol, Clark Keelock Chow
Cyclization Studies Involving The Synthesis Of 5-Substituted-1-Naphthol, Clark Keelock Chow
Dissertations and Theses
The γ-o-substituted-phenylparaconic acids were prepared by a method patterned after that of Fuson. These paraconic acids were prepared in good yield. A re-investigation of the Perkin and Fittig methods of preparing γ-phenylisocrotonic acid was carried out without success.
The synthesis of γ-o-halophenylisocrotonic acids by thermal, and catalyzed decarboxylation of γ-o-halophenylparaconic acid, have been carried out in good yield. An effective catalyst, optimum temperature and reaction period of decarboxylation of the γ-o-halophenylparaconic acids have been determined. Infrared absorptions have characterized the γ-o-halophenylisocrotonic acids formed to be in the stable trans form. …
A Comparison Of The Effects Of Fluoride And Chloride Ions Upon The Activity Of Yeast Alcohol Dehydrogenase, Ellen J. Hannan
A Comparison Of The Effects Of Fluoride And Chloride Ions Upon The Activity Of Yeast Alcohol Dehydrogenase, Ellen J. Hannan
Dissertations and Theses
Very little is known about the effect of hydrofluoric acid and of the fluoride ion on enzyme systems. The purpose of this work was to determine the effect of hydrofluoric acid and of the fluoride ion on the enzyme, yeast alcohol dehydrogenase and to distinguish between the effect of the fluoride ion and of hydrofluoric acid. The rate of the enzyme reaction was followed spectrophotometrically at 340 mμ on the Cary 14 Model spectrophotometer according to the method of Racker. The data taken from the instrument recordings were plotted on two types of graphs, the Lineweaver-Burk plot and the Hanes …
Directional Correlation Of The 346-136 Kev Gamma-Gamma Cascade In Ta¹⁸¹, Robert Allan Wilson
Directional Correlation Of The 346-136 Kev Gamma-Gamma Cascade In Ta¹⁸¹, Robert Allan Wilson
Dissertations and Theses
The directional correlation of the 346-136 Kev gamma-gamma cascade in Ta¹⁸¹ was measured using the delayed coincidence method with a source of Hf¹⁸¹ in 27 N HF. The contributions to the composite delayed coincidence spectrum of the interfering 133-482 Kev and 133-346 Kev cascades were removed by the subtraction from this spectrum of appropriate 133-482 Kev pure delayed coincidence data. The extracted 346-136 Kev coincidence data then yielded the correlation coefficients A₂₂ = 0.190±0.011 and A₄₄. = -0.025±0.024 that are consistent with the established spin sequence 5/2(E2)9/2(M1 + E2)7/2 and with an admixture of 16.2%±1. 2% E2 radiation in the …
Steady-State And Transient Currents In Organic Liquids By Injection From A Tunnel Cathode, Pavel Smejtek, David G. Onn, M. Silver
Steady-State And Transient Currents In Organic Liquids By Injection From A Tunnel Cathode, Pavel Smejtek, David G. Onn, M. Silver
Physics Faculty Publications and Presentations
Experimental data are presented on the currents induced in organic liquids by injection from a tunnel cathode. The injection level was varied over a wide range resulting in almost no space‐charge limitation to almost complete space‐charge limitation. Results were different from that usually observed in solids, in that at low fields, the steady‐state current was proportional to V², while at high fields the current was proportional to V. By proper choice of electrode spacing and applied voltage, space‐charge‐limited current transients as low as 10⁻¹¹ A∕cm² and 5 sec transit times were observed. A smooth transition between the electrode‐limited and the …
Applications Of Modified Wittig Reaction To Butatriene Synthesis, John Pearson
Applications Of Modified Wittig Reaction To Butatriene Synthesis, John Pearson
Dissertations and Theses
The preparation of allenes by the condensation of an acyl chloride with a phosphonium ylid and subsequent elimination of an acid salt and a phosphonium oxide has been established by Bestmann and Hartung. It was felt that this process could be expanded to include the synthesis of butatrienes. Butatrienes are stabilized by aromatic substituents while aromatic substituents decrease the nucleophilicity and reactivity of the phosphonium ylids to be used in the synthesis of the butatrienes. The ylids employed were carbomethoxyphenylmethylenetriphenyl phosphorane, and a new compound, carbethoxyphenylmethylenetriphenyl phosphorane, both of which failed to form alkylated condensation products. Both ylids were prepared …
Bacterial Degradation Of Methyl Dehydroabietate, Burl C. Carter
Bacterial Degradation Of Methyl Dehydroabietate, Burl C. Carter
Dissertations and Theses
Bacteria (Arthrobacter sp.), isolated from lodgepole pine (Pinus contortus), are capable of utilizing methyl dehydroabietate as the sole source of carbon. Degradation products of methyl dehydroabietate have been obtained by manually extracting the cell-free supernatant solution of a liquid growth medium with methylene chloride. Gas chromatography (G. L. C.) was used for separation of the neutral products. The acid products were converted to their methyl esters diazomethane and then separated by gas chromatography. Structures have been proposed for two G. L. C. fractions (V, II) on the basis of infrared (I.R.) and mass spectral (M. S.) data. …
"Planetary Exploration (Lecture Two)", Carl Sagan
"Planetary Exploration (Lecture Two)", Carl Sagan
Special Collections: Oregon Public Speakers
Requested by: "Standing order from Science" "Planetary Exploration"
"Planetary Exploration (Lecture One)", Carl Sagan
"Planetary Exploration (Lecture One)", Carl Sagan
Special Collections: Oregon Public Speakers
No abstract provided.
On The Definition Of Self-Organizing Systems, George G. Lendaris
On The Definition Of Self-Organizing Systems, George G. Lendaris
Systems Science Faculty Publications and Presentations
Published in: Proceedings of the IEEE ( Volume: 52, Issue: 3, March 1964)
"The Effects Of Radioactive Fallout And Disarmament", Linus Carl Pauling
"The Effects Of Radioactive Fallout And Disarmament", Linus Carl Pauling
Special Collections: Oregon Public Speakers
There is a slight lapse of about 5 seconds where re-recorded overlap didn't quite cover. Recorded on a Berlout 33 stereo recorded using both tracks in one direction.
"American Foreign Policy In The Atomic Age", Arthur Meier Schlesinger Jr.
"American Foreign Policy In The Atomic Age", Arthur Meier Schlesinger Jr.
Special Collections: Oregon Public Speakers
No abstract provided.