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Articles 34621 - 34650 of 36535

Full-Text Articles in Physical Sciences and Mathematics

New Relativistic Paradoxes And Open Questions, Florentin Smarandache Jan 1983

New Relativistic Paradoxes And Open Questions, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

Following the Special Theory of Relativity, Florentin Smarandache generalized the Lorentz Contraction Factor to an Oblique-Contraction Factor, which gives the contraction factor of the lengths moving at an oblique angle with respect to the motion direction. He also proved that relativistic moving bodies are distorted, and he computed the Angle-Distortion Equations.

He then showed several paradoxes, inconsistencies, contradictions, and anomalies in the Theory of Relativity.

According to the author, not all physical laws are the same in all inertial reference frames, and he gives several counter-examples. He also supports superluminal speeds, and he considers that the …


Atlas Of High Resolution Infrared Spectra Of Carbon Dioxide: February 1983 Edition, D. Chris Benner Jan 1983

Atlas Of High Resolution Infrared Spectra Of Carbon Dioxide: February 1983 Edition, D. Chris Benner

Arts & Sciences Articles

No abstract provided.


Stopping Power Of K Electrons At Extreme Relativistic Energies, P.T. Leung, M. L. Rustgi Jan 1983

Stopping Power Of K Electrons At Extreme Relativistic Energies, P.T. Leung, M. L. Rustgi

Physics Faculty Publications and Presentations

The recent work of Anholt (1979) on K-vacancy production by relativistic projectiles has been applied to calculate the stopping power of the K electrons. The results show that for protons of energy ~10³ GeV and heavy target elements, the relativistic contributions to the stopping power amount to several times the results due to the longitudinal terms obtained from Walske's (1956) work.


Intermolecular Interactions For Phosphatidyl Choline And Phosphatidyl Ethanolamine, Tony Flaim, Stig Friberg, Patricia L.M. Plummer Jan 1983

Intermolecular Interactions For Phosphatidyl Choline And Phosphatidyl Ethanolamine, Tony Flaim, Stig Friberg, Patricia L.M. Plummer

Chemistry Faculty Research & Creative Works

Intermolecular interaction between pairs of methylphosphocholine (MPC) and methylphosphoethanolamine were calculated using an extended CNDO/2 program. Experimentally determined conformations were used for the ethanolamine and choline groups. In the methylphosphocholine the major interaction was intramolecular, involving the phosphate ester-choline groups, while in the ethanolamine the maximum attraction was intermolecular between the ethanolamine and the phophate ester of a neighboring molecule(s). © 1983.


Experimental Evidence For The Acceleration Of Thermal Electrons By Ion Cyclotron Waves In The Magnetosphere, A. J. Norris, J.F. E. Johnson, Jan Josef Sojka, G. L. Wrenn, N. Cornilleau-Wehrlin, S. Perraut, A. Roux Jan 1983

Experimental Evidence For The Acceleration Of Thermal Electrons By Ion Cyclotron Waves In The Magnetosphere, A. J. Norris, J.F. E. Johnson, Jan Josef Sojka, G. L. Wrenn, N. Cornilleau-Wehrlin, S. Perraut, A. Roux

All Physics Faculty Publications

Ion cyclotron waves (ICWs) at frequencies just above f He+ , the helium gyrofrequency, are often observed by the ESA satellites GEOS 1 and GEOS 2. Young et al. (1981) have shown the close connection between these ICWs and the presence of thermal He+ ions in the outer magnetosphere. The purpose of this paper is to provide experimental evidence for the acceleration of thermal electrons by the large amplitude ICWs. The wave power in the ultra low frequency (ULF) range near f He+ is compared with the distribution function of low energy electrons, measured by instruments aboard the GEOS satellites. …


Preferential Perpendicular Acceleration Of Heavy Ionospheric Ions By Interactions With Electrostatic Hydrogen Cyclotron Waves, Nagendra Singh, Robert W. Schunk, Jan Josef Sojka Jan 1983

Preferential Perpendicular Acceleration Of Heavy Ionospheric Ions By Interactions With Electrostatic Hydrogen Cyclotron Waves, Nagendra Singh, Robert W. Schunk, Jan Josef Sojka

All Physics Faculty Publications

The energization of heavy ionospheric ions by electrostatic hydrogen cyclotron (EHC) waves is examined. In particular, the problem of preferential perpendicular acceleration of heavy ions above 5000 km along auroral field lines is examined critically. Observations have indicated that above this altitude the occurrences of ion beams and EHC waves are highly correlated and that the occurrence rates are high. The EHC waves are found to be coherent. The energization process is examined in the light of interactions of a single coherent wave with the ions. The interactions can be stochastic or nonstochastic, depending on the parameters of the wave …


Incoherent Scatter Measurements Of Ion-Neutral Collision Frequencies And Temperatures In The Lower Thermosphere Of The Auroral Region, C. Lathuillere, Vincent B. Wickwar, W. Kofman Jan 1983

Incoherent Scatter Measurements Of Ion-Neutral Collision Frequencies And Temperatures In The Lower Thermosphere Of The Auroral Region, C. Lathuillere, Vincent B. Wickwar, W. Kofman

All Physics Faculty Publications

Incoherent scatter observations performed in March and November 1978 at Chatanika have been used for studying the lower thermosphere in the auroral region. Neutral temperatures and densities have been found during periods without Joule heating. We present mean profiles of temperatures and collision frequencies (approximately proportional to neutral densities) for each month and profiles obtained during four specific nights. Between 93 km and 110 km the mean profiles of temperature are in good agreement with the Jacchia (1971) model, and the profiles of collision frequency are similar to those deduced from the model. Consistency checks between these collision frequencies and …


Comparison Of Model High-Latitude Electron Densities With Millstone Hill Observations, Jan Josef Sojka, Robert W. Schunk, J. V. Evans, J. M. Holt, R. H. Wand Jan 1983

Comparison Of Model High-Latitude Electron Densities With Millstone Hill Observations, Jan Josef Sojka, Robert W. Schunk, J. V. Evans, J. M. Holt, R. H. Wand

All Physics Faculty Publications

Model predictions of the diurnal variations of plasma convection velocities and electron densities in the high-latitude ionosphere were compared with Millstone Hill incoherent scatter radar observations for an equinox day on which there was moderate magnetic activity. On the observation day, three major morphological features were evident at 500 km, including a dayside high density region, a nightside mid-latitude trough, and a region of slightly enhanced densities in the auroral zone. Although the dayside high density region was due to solar EUV radiation, it was not symmetrical about local noon (1000-1900 LT sector) owing to the effect of horizontal transport. …


Large-Scale Counterstreaming Of H+ And He+ Along Plasmaspheric Flux Tubes, P. G. Richards, Robert W. Schunk, Jan Josef Sojka Jan 1983

Large-Scale Counterstreaming Of H+ And He+ Along Plasmaspheric Flux Tubes, P. G. Richards, Robert W. Schunk, Jan Josef Sojka

All Physics Faculty Publications

An interhemispheric plasma transport model has been used to study the flow characteristics of H+, He+, and O+ along closed geomagnetic field lines for solstice conditions at noon local time. The calculations were carried out for the flux tube that passes through Millstone Hill. Both symmetric and asymmetric neutral winds in the conjugate ionospheres were considered. Initially, the flux tube content was partially depleted, and the subsequent refilling was studied until a steady state flow was established between the winter and summer hemispheres. The main conclusion to be drawn from this study is that H+-He+ counterstreaming can be expected along …


Fluorescence Quenching At High Quencher Concentrations, David Peak, T C. Werner, R M. Dennin Jr., J K. Baird Jan 1983

Fluorescence Quenching At High Quencher Concentrations, David Peak, T C. Werner, R M. Dennin Jr., J K. Baird

All Physics Faculty Publications

Chemical reactions occurring in dense media at high reactant concentrations can be described by rate ‘‘constants’’ which are actually functions of concentration. We present a theoretical model in which this so‐called rate constant ‘‘renormalization’’ occurs for the specific case of fluorescence quenching in solution. We show that both the quenching and the excitation rate constants can become concentration dependent. We fit our theory to several sets of experimental data—our own and some from the literature—and show that excellent agreement is obtained by varying a single free parameter, namely, the efficiency with which a fluorophore‐quencher collision leads to a quench of …


Characteristics Of Thermal And Suprathermal Ions Associated With The Dayside Plasma Trough As Measured By The Dynamics Explorer Retarding Ion Mass Spectrometer, Jan Josef Sojka, Robert W. Schunk, J.F. E. Johnson, J. H. Waite, C. R. Chappell Jan 1983

Characteristics Of Thermal And Suprathermal Ions Associated With The Dayside Plasma Trough As Measured By The Dynamics Explorer Retarding Ion Mass Spectrometer, Jan Josef Sojka, Robert W. Schunk, J.F. E. Johnson, J. H. Waite, C. R. Chappell

All Physics Faculty Publications

The retarding ion mass spectrometer (RIMS) instrument on Dynamics Explorer 1 has carried out high-altitude measurements of the polar wind. During an outbound pass through the outer plasmasphere and plasma trough at 0900 LT the RIMS instrument measured the detailed characteristics of the thermal and suprathermal ions. Three distinct populations were observed: (1) thermal ions (H+ and He+) with densities ranging from > 500 ions/cm3 to < 1 ion/cm3, temperatures around 2 eV (20,000° K), and H+/He+ density ratios of 2 to 4, (2) warm anisotropic plasma with densities ranging from 2 to 12 ions/cm …


A Theoretical Study Of The High Latitude F Region’S Response To Magnetospheric Storm Inputs, Jan Josef Sojka, Robert W. Schunk Jan 1983

A Theoretical Study Of The High Latitude F Region’S Response To Magnetospheric Storm Inputs, Jan Josef Sojka, Robert W. Schunk

All Physics Faculty Publications

The response of the polar ionosphere to magnetospheric storm inputs was modeled. During the storm the two major processes that couple the F region to the magnetosphere, namely the electric field distribution and the particle precipitation from the magnetosphere, undergo drastic modification on relatively short F region time scales. These time-dependent changes are not simply related to the F region storm time dependent changes. The lower F region responds on a time scale of only minutes to the storm associated changes in the auroral precipitating electron flux, owing to the dominance of chemistry production-loss mechanisms over transport processes. At higher …


First Vhf Auroral Radarinterferometer Observations, J. Providakes, W. E. Swartz, D. T. Farley, Bela G. Fejer Jan 1983

First Vhf Auroral Radarinterferometer Observations, J. Providakes, W. E. Swartz, D. T. Farley, Bela G. Fejer

Bela G. Fejer

The radar interferometer technique first used at the magnetic equator in Peru is also a very powerful means for studying auroral plasma instabilities. We present here the first results, obtained with a 49.92 MHz, 20-25 KW peak power pulsed radar located in Ithaca, NY (42.5° N, 76.4° W). Strong auroral echoes were obtained during several highly active periods. Phase differences between the signals received on the two antennas accurately determine the E-W position, within the scattering volume, of localized scattering centers, and changes in this phase determine the corresponding velocity. The signal Doppler shift describes radial (essentially N-S) motion. The …


Universal Stationary-Phase Treatment Of Far-Wing And Excimer Spectral Line Shapes, Ronald James Bieniek, T. J. Streeter Jan 1983

Universal Stationary-Phase Treatment Of Far-Wing And Excimer Spectral Line Shapes, Ronald James Bieniek, T. J. Streeter

Physics Faculty Research & Creative Works

When two atoms are in proximity, their resonance lines are broadened because of the formation of molecular potentials, between which photon transitions can occur. The level of experimental refinement in measuring excimer and collisional far-wing spectra calls for interpretive theoretical methods that accurately treat the observed structure in line shapes. Of particular interest are satellites and undulations, for they can give much information on intermolecular potentials. We derive an expression for T-matrix elements, based on JWKB wave functions and stationary-phase techniques, that is universally applicable to situations with one, two, or more Condon points. Each transition point is treated individually, …


Thermal Decomposition Kinetics Of Iodine‐Doped Polyacetylene In Vacuum, J. ‐E Osterholm, H. Yasuda, L. L. Levenson Jan 1983

Thermal Decomposition Kinetics Of Iodine‐Doped Polyacetylene In Vacuum, J. ‐E Osterholm, H. Yasuda, L. L. Levenson

Physics Faculty Research & Creative Works

The thermal stability of iodine‐doped polyacetylene films, (CHIy)x, has been studied by means of electrical conductivity measurements, measurements on weight loss, and mass spectrometric analysis of desorbing species. When heated between room temperature and 125°C in vacuum, these films proved to be of poor thermal stability, being unstable at temperatures above 20°C. During the thermal treatments, molecular iodine desorbs from the films, resulting in an appreciable dopant weight loss with accompanying decrease in the electrical conductivity. The decomposition process does not follow simple kinetics. Copyright © 1983 John Wiley & Sons, Inc.


Homogeneous Nucleation Of Toluene, John L. Schmitt, R. A. Zalabsky, G. W. Adams Jan 1983

Homogeneous Nucleation Of Toluene, John L. Schmitt, R. A. Zalabsky, G. W. Adams

Physics Faculty Research & Creative Works

The authors have used a fast expansion chamber to measure the homogeneous nucleation rate of toluene as a function of temperature and supersaturation. The measured nucleation rate ranges from 102 to 105 drops/cm3 s over a temperature range of 215-267 K. The measurements are compared with the "classical" nucleation theory and with the RKC theory. The inclusion of the RKC replacement factor brings the data into good agreement with theory using physically realistic values of the surface tension and the sticking coefficient. An empirical curve fit to the data is presented as well as a full listing of the thermodynamic …


Collisions Of Fast Highly Charged Ions In Gas Targets: Ionization, Recoil-Ion Production, And Charge Transfer, A. S. Schlachter, K. H. Berkner, H. F. Beyer, W. G. Graham, W. Groh, R. Mann, A. Müller, Ronald E. Olson, R. V. Pyle, J. W. Stearns, J. A. Tanis Jan 1983

Collisions Of Fast Highly Charged Ions In Gas Targets: Ionization, Recoil-Ion Production, And Charge Transfer, A. S. Schlachter, K. H. Berkner, H. F. Beyer, W. G. Graham, W. Groh, R. Mann, A. Müller, Ronald E. Olson, R. V. Pyle, J. W. Stearns, J. A. Tanis

Physics Faculty Research & Creative Works

Electron-capture, ionization, and recoil-ion-production cross-sections are measured and calculated for fast highly charged projectiles in hydrogen and rare-gas targets. Recoil-ion-production cross-sections are found to be large; the low energy and high charge states of the recoil ions make them useful for subsequent collision studies. © 1983 IOP Publishing Ltd.


A Chronology Of The Nuclear Arms Race, David W. Hafemeister Jan 1983

A Chronology Of The Nuclear Arms Race, David W. Hafemeister

Physics

No abstract provided.


Interactive Computer Graphics: The Arms Race, David W. Hafemeister Jan 1983

Interactive Computer Graphics: The Arms Race, David W. Hafemeister

Physics

No abstract provided.


Nanosecond Optical Transmission Studies Of Laser Annealing In Ion-Implanted Silicon-On-Sapphire, M. C. Lee, H. W. Lo, A. Aydinli, G. J. Trott, A. Compaan, Edward Boyd Hale Jan 1983

Nanosecond Optical Transmission Studies Of Laser Annealing In Ion-Implanted Silicon-On-Sapphire, M. C. Lee, H. W. Lo, A. Aydinli, G. J. Trott, A. Compaan, Edward Boyd Hale

Physics Faculty Research & Creative Works

Time-resolved optical transmission has been studied using 633 and 514 nm CW probes on ion-implantation-amorphized silicon-on-sapphire during annealing by a 10 nsec, ⊥ J/cm2 pulse at either 532 nm or 485 nm. As recrystallization sets in the transmitted signal at 514 nm rises by ⊥ 103 in ⊥ 60 nsec and provides a measure of regrowth velocity. Beyond 200 nsec the much slower transmission rise is used to provide an estimate of the Si cooling rate. The difference in transmission observed between initially crystalline and initially amorphous Si provide an estimate of the latent heat of recrystallization of the amorphous …


Vibrational-Rotational Deexcitation Of Hf In Collision With He, Ronald James Bieniek Jan 1983

Vibrational-Rotational Deexcitation Of Hf In Collision With He, Ronald James Bieniek

Physics Faculty Research & Creative Works

State-to-state cross sections are reported for vibrational-rotational transitions for HF in collisions with He, at collisional energies of 0.5 and 1.0 eV. These were computed within the infinite-order sudden (IOS) approximation using adiabatic, distorted-wave techniques. Values are tabulated for the vibrational-rotational deexcitation sequences (v,j)→(v-1, 0), with v=1, 2, 3, 4 and j=0-40. These quenching cross sections can be used in conjunction with IOS factorization formulas to compute VRT cross sections for final rotational states other jf=0. In addition to IOS results, vibrational quenching cross sections were computed using the much more simple breathing-sphere technique. The breathing-sphere results compare favorably to …


A General Nmr Spectral Density And Its Experimental Verification, A. M. Albano, Peter A. Beckmann, M. E. Carrington, F. A. Fusco, A. E. O'Neill, M. E. Scott Jan 1983

A General Nmr Spectral Density And Its Experimental Verification, A. M. Albano, Peter A. Beckmann, M. E. Carrington, F. A. Fusco, A. E. O'Neill, M. E. Scott

Physics Faculty Research and Scholarship

The authors develop a new general spectral density for use in interpreting nuclear spin-lattice relaxation measurements in molecular solids where molecular and/or intramolecular reorientation is responsible for the relaxation. They show that the simplest case of the general theory fits both the temperature and Lamor frequency dependence of some very complicated relaxation measurements which could not be previously fitted using several standard spectral densities. The relationship of the spectral density to a distribution of molecular potentials is briefly outlined.


Comment On Coefficients Of Fractional Parentage Of The Form (L2L+1|}L2L+2), Anthony F. Starace Jan 1983

Comment On Coefficients Of Fractional Parentage Of The Form (L2L+1|}L2L+2), Anthony F. Starace

Anthony F. Starace Publications

For the special case of half-filled subshells, Racah showed in 1943 that his formula relating the coefficients of fractional parentage for a given particle configuration to those for the corresponding hole configuration requires an additional phase factor (-1) (v-1)/2, where v is the seniority of the half-filled configuration. This phase factor is incorrectly printed in Racah's 1943 paper as (-1) v-1/2. Furthermore, this phase factor is omitted in the 1952 paper by Rosenzweig, resulting in sign errors in the table of (d5|}d6) coefficients. These rather old errors have often …


Catastrophes In The Elmo Bumpy Torus, Alkesh R. Punjabi Jan 1983

Catastrophes In The Elmo Bumpy Torus, Alkesh R. Punjabi

Dissertations, Theses, and Masters Projects

Experimentally it is observed that the plasma in Elmo Bumpy Torus (EBT) shows discontinuous changes in the electron line density, electron and ion temperatures and fluctuation levels as the ambient gas pressure or electron cyclotron heating is varied continuously. We use the Point Model of Hedrick et al. for the toroidal core plasma in EBT. The Point Model is not a gradient dynamic system. Hence the Elementary Catastrophe Theory is not directly applicable to the Point Model. Nonetheless, the Point Model equilibria will be shown to exhibit properties which are quite akin to the canonical cusp catastrophe. The ambipolar electric …


A General Theory Of Electron Detachment In Negative Ion Collisions, Tzuu-Shin Wang Jan 1983

A General Theory Of Electron Detachment In Negative Ion Collisions, Tzuu-Shin Wang

Dissertations, Theses, and Masters Projects

In this thesis a general theory of electron detachment in slow collisions of negative ions with atoms is presented. The theory is based upon a semiclassical close-coupling framework, following the work of Taylor and Delos. The Schrodinger equation is reduced, under certain assumptions, to a non-denumerably infinite set of coupled equations. We develop a new method for solving these equations that is more general than the methods used by Taylor and Delos. A zero-order approximation of our solution is applied to the case of H('-)(D('-)) on Ne collisions, the results are compared with the experimental data, and we find good …


Long-Time States Of Inverse Cascades In The Presence Of A Maximum Length Scale, Murshed Hossain Jan 1983

Long-Time States Of Inverse Cascades In The Presence Of A Maximum Length Scale, Murshed Hossain

Dissertations, Theses, and Masters Projects

It is shown numerically, both for the two-dimensional Navier-Stokes equations and for two-dimensional magnetohydrodynamics, that the long-time asymptotic state in a forced inverse-cascade situation is one in which the spectrum is completely dominated by its own fundamental. The growth continues until the fundamental is dissipatively limited by its own dissipation rate. An algebraic model is proposed for the dynamics of such a final state.


Nmr Study Of Molecular Motions In Two Disordered Organic Solids, Philip L. Kuhns Jan 1983

Nmr Study Of Molecular Motions In Two Disordered Organic Solids, Philip L. Kuhns

Dissertations, Theses, and Masters Projects

The molecular motions are studies in two disordered materials that undergo glass transitions. Glycerol is a conventional glass former and cyclohexanol is an orientational glass former.;The technique used in the glycerol experiments was spectral hole burning. Chemical shift anisotropy produces inhomogeneous broadening of NMR lines in orientationally disordered and polycrystalline solids. By saturating or inverting a portion of the anisotropic line, 'burning a hole', molecules of certain orientations are tagged. Subsequent molecular reorientations result in spectral diffusion which is not related to spin-spin interactions. By measuring the broadening and recovery of the hole as a function of time, detailed knowledge …


A Precision Measurement Of The Magnetic Moment Of The Sigma Minus Hyperon, David William Hertzog Jan 1983

A Precision Measurement Of The Magnetic Moment Of The Sigma Minus Hyperon, David William Hertzog

Dissertations, Theses, and Masters Projects

A new measurement of the magnetic moment of the (SIGMA)('-) hyperon has been made and the result is (mu)((SIGMA)('-)) = -1.111 (+OR-) 0.031 (+OR-) 0.011 nuclear magnetons.;Negative kaons from a low-energy separated beam at the Alternating Gradient Synchrotron of the Brookhaven National Laboratory were brought to rest in a novel laminar target consisting of thin metal foils immersed in liquid hydrogen. The production of (SIGMA)('-) hyperons occurred primarily through the reaction K('-)p(--->)(SIGMA)('-)(pi)('+). (SIGMA)('-) hyperon production was tagged by the identification of the energetic (pi)('+). Many of the (SIGMA)('-) so produced stopped in nearby foils of Pb (or W) where …


Theoretical Studies Of Water On Substrates, Sergio M. Terrazas Jan 1983

Theoretical Studies Of Water On Substrates, Sergio M. Terrazas

Doctoral Dissertations

"Model interaction potentials for H2O on a basal f)-silver iodide substrate containing two types of defects, a potassium impurity and a four atomic layer ledge, are used to calculate optimal binding energy contours for the adsorbed H2O molecule. (J. Phys. Chern. 84, 1473(1980)). The model substrate with the potassium impurity appears to increase the optimal binding energy at the preferred adsorption sites to 23 kcal/rnol -- a value approximately 40 % larger than the maximal binding energy sites on the defect-free model silver-exposed basal plane of AgI. The impurity also distorts the hexagonal symmetry of the …


Homogeneous Nucleation Of Nonane In Argon Using An Expansion Cloud Chamber, Gregg Wesley Adams Jan 1983

Homogeneous Nucleation Of Nonane In Argon Using An Expansion Cloud Chamber, Gregg Wesley Adams

Doctoral Dissertations

"The homogeneous nucleation rate of nonane has been measured using an expansion cloud chamber. Data were obtained for pre-expansion temperatures of 45°C, 35°C, 25°C, 15°C, 5°C, and -5°C. The measured nucleation rate ranges from 102 to 105 drops/cm3 -sec over a temperature range of 216 K to 270 K. The data set is sufficiently extensive to provide a detailed test for nucleation theories applied to nonane. The measured rates are compared with the "classical" nucleation theory and with a modified classical theory using the replacement factor of Reiss, Katz and Cohen (RKC). It is found that neither …