Physical Sciences and Mathematics Commons^™

Emission Line Profile Shapes From Anisotropic Scattering In Planar Equatorial Disks., R. Ignace

Richard Ignace

The consequences of anisotropic resonance line scattering for the emission profiles of equatorial disks are considered. In particular the opportunity to infer the disk velocity field owing to the anisotropic scattering is discussed. Analytic expressions for the profile shapes are derived for the cases of constant expansion and rotation, and numerical results are given for more realistic disk velocity fields of linear expansion and Keplerian rotation. The essential result is that the anisotropic line scattering produces a different profile signature in expanding disks as compared to rotating disks, owing to the difference in the isovelocity pattern of the two cases …

Inference Of Steady Stellar Wind V(R) Laws From Optically Thin Emission Lines Iii. Inversion Of Total Line Intensity Distributions., R. Ignace, J. C. Brown, J. E. Milne, J. P. Cassinelli

Richard Ignace

The variation with wavelength for a sequence of total intensities of stellar wind lines is considered as a basis for deriving the wind velocity law v(r). In particular, we focus on the case where the continuum formation in the wind is dominated by the free-free opacity so that the inner radius increases with wavelength, as is realized in some massive winds like those of the Wolf-Rayet stars. The line emission in the wind occurs exterior to the continuum photosphere, hence lines observed at different wavelengths probe different regions of the wind acceleration. A major consequence of these physical conditions is …

Mid- And Low-Latitude Prompt-Penetration Ionospheric Zonalplasma Drifts, Bela G. Fejer, L. Scherliess

Bela G. Fejer

We have used ion drift observations from the DE-2 satellite to determine the latitudinal variation and the temporal evolution of mid- and low-latitude prompt penetration zonal plasma drifts driven by magnetospheric electric fields. Our results indicate that sudden increases in convection lead to predominantly westward perturbation drifts which decrease equartorwards and have largest amplitudes in the dusk-midnight sector. The diurnal perturbation drift patterns shift to later local times with increasing storm time and decay to new quasi-equilibrium values in about 2 hours, as the ring current readjusts to the new polar cap potential. The daily and latitudinal variations and temporal …

26. Itaru Mita, Otto Vogl

Otto Vogl

No abstract provided.

Investigation Of The 10b(Γ,P) Reaction Using Tagged Photons, L J. De Bever, R S. Hicks, R A. Miskimen, Gerald Alvin Peterson

Gerald Alvin Peterson

The reaction 10B(γ,p) has been studied using tagged photons of mean energies Eγ=57.6 and 72.9 MeV. Angular distributions and derived single-particle momentum distributions for protons leading to the ground state of 9Be and higher excited states are compared to various calculations made using model parameters constrained by 10B(e,e′p)9Be and 9Be(p,p′)9Be measurements. The effects of varying final-state interactions (including channel couplings) and meson exchange currents are considered. A sizable discrepancy between direct-knockout calculations and the experimental results is observed. If meson exchange currents are included in an approximate fashion, a good description of the 10B(γ,p0)9Be data is found.

Overview Of Statistical Tools Used In Supportability Analysis, Caroline Lubert

Caroline P Lubert

No abstract provided.

2-Phenyl-3-(5,6,7,7a-Tetrahydro-1h,3h-Pyrrolo[1,2-C]Oxazol-3-Ylidene)-1-Propene-1,1-Dicarbonitrile And 4-(4-Methoxyphenyl)-2,6-Bis(Methylthio)Pyridine-3-Carbonitrile, M. George, S. Das, C.V. Ashokan, N.P. Rath, M.V. George

Nigam Rath

27. Per Flodin, Otto Vogl, Kerstin Meijer-Flodin

Otto Vogl

No abstract provided.

Morphogenesis By Symbiogenesis, Michael J. Chapman, Lynn Margulis

Lynn Margulis (1938 - 2011)

Here we review cases where initiation of morphogenesis, including the differentiation of specialized cells and tissues, has clearly evolved due to cyclical symbiont integration. For reasons of space, our examples are drawn chiefly from the plant, fungal and bacterial kingdoms. Partners live in symbioses and show unique morphological specializations that result when they directly and cyclically interact. We include here brief citations to relevant literature where plant, bacterial or fungal partners alternate independent with entirely integrated living. The independent, or at least physically unassociated stages, are correlated with the appearance of distinctive morphologies that can be traced to the simultaneous …

Measurements Of The Δ(1232) Transition Form Factor And The Ratio Σn/Σp From Inelastic Electron-Proton And Electron-Deuteron Scattering, L M. Stuart, R S. Hicks, R A. Miskimen, Gerald Alvin Peterson, S H. Rokni

Gerald Alvin Peterson

Measurements of inclusive electron-scattering cross sections using hydrogen and deuterium targets in the region of the Δ(1232) resonance are reported. A global fit to these new data and previous data in the resonance region is also reported for the proton. Transition form factors have been extracted from the proton cross sections for this experiment over the four-momentum transfer squared range 1.64

Charge-Correlation Effects In Calculations Of Atomic Short-Range Order In Metallic Alloys, F. J. Pinksi, J. B. Staunton, Duane D. Johnson

Duane D. Johnson

The “local” chemical environment that surrounds an atom directly influences its electronic charge density. These atomic charge correlations play an important role in describing the Coulomb and total energies for random substitutional alloys. Although the electronic structure may be well represented by a single-site theory, such as the coherent potential approximation, the electrostatic energy is not as well represented when these charge correlations are ignored. For metals, including the average effect from the charge correlation coming from only the nearest-neighbor shell has been shown to be sufficient to determine accurately the energy of formation. In this paper, we incorporate such …

Emisja Związków Fluoru Z Procesów Hutnictwa Żelaza, Marian Mazur, Marek Bogacki, Robert Oleniacz

Robert Oleniacz

The paper presents the results of a comprehensive study of issues related to emissions of fluorine compounds from ferrous metallurgy processes carried out over the last few years. As part of this study raw materials used in these processes were analyzed in terms of fluorine content and its impact on the amount of air emissions of fluorine compounds. Also determined by measuring the concentration levels and emissions of fluorine in the gaseous and solid phase, including water-soluble compounds (considered to be toxic).

English title: Emissions of fluorine compounds from the processes of ferrous metallurgy.

A Comparative Study Of Molecular Similarity, Statistical, And Neural Methods For Predicting Toxic Modes Of Action, Steven P. Bradbury, Subhash C. Basak, Gregory D. Grunwald, George E. Host, Gerald J. Niemi

Steven P. Bradbury

Quantitative structure–activity relationship (QSAR) models are routinely used in predicting toxicologic and ecotoxicologic effects of untested chemicals. One critical factor in QSAR-based risk assessment is the proper assignment of a chemical to a mode of action and associated QSAR. In this paper, we used molecular similarity, neural networks, and discriminant analysis methods to predict acute toxic modes of action for a set of 283 chemicals. The majority of these molecules had been previously determined through toxicodynamic studies in fish to be narcotics (two classes), electrophiles/proelectrophiles, uncouplers of oxidative phosphorylation, acetylcholinesterase inhibitors, and neurotoxicants. Nonempirical parameters, such as topological indices and …

28. Vivian Stannett, Otto Vogl, Susanne S. Stannett

Otto Vogl

No abstract provided.

Improving Performance By Branch Reordering, Minghui Yang, Gang-Ryung Uh, David B. Whalley

Gang-Ryung Uh

Sediment Control At Water Intakes Along Sand Bed Rivers, Fred L. Ogden

Fred L. Ogden

Results from five physical hydraulic model studies of riverside water intakes situated along the Missouri River reach between Sioux City, Iowa, and St. Louis, Missouri, are presented. Movable-bed, undistorted Froude-scale models are used to determine the effectiveness of structural modifications in the vicinity of the intake to limit the influx of bed-load sediments. Solutions developed in each case include a series of submerged flow-turning vanes located on the riverward side of the intake. A sediment-barrier wall between the vanes and intake ...

Atmospheric Circulation Anomalies Associated With 1996/1997 Summer Precipitatipn Events On Sajama Ice Cap, Bolivia, Mathias Vuille, Douglas R. Hardy, Carsten Braun, Frank Keimig, Raymond S. Bradley

Raymond S Bradley

The analysis of atmospheric circulation anomalies related to snowfall eVents on Sajama volcano (Bolivian Andes) provides important information for the calibration of an ice core, recently recovered from the summjt. Seventeen precipitation episodes were recorded on Sajama volcano during the 1996/1997 summer season (November 1996 to Marcb 1997) by snow depth sensors and additional measurements of an automatic weather station located on the summit. The analysis of atmospheric circulation patterns during these events is pased on zonal and meridional wind, air temperature, relative humiqity, geopotential height and horizontal divergence at three pressure levels (400, 500, and 700 hPa levels), atmosphenc …

Resistivity Of Boron-Doped Diamond Microcrystals, M. D. Jaeger, S. Hyun, Anthony Roy Day, M. F. Thorpe, B. Golding

Anthony Roy Day

We describe measurements of the electrical resistivity of micron-size crystallites of boron-doped diamond. Electron-beam lithography was employed for writing sample-specific contacts on small, well-faceted diamond crystals grown by chemical-vapor deposition on silicon substrates. After generating a three-dimensional computer model of the crystallite, a finite-element analysis was used to calculate the internal electrostatic potential distribution. Multiterminal resistance measurements, in conjunction with a computed geometrical factor, enabled the absolute resistivity to be determined. We find that the resistivities obtained from two different crystallites agree to better than 10%. The results are compared with transport measurements on a large-area homoepitaxial diamond film grown …

Radial Dependence Of The Nucleon Effective Mass In 10b, L J. De Bever, R S. Hicks, R A. Miskimen, Gerald Alvin Peterson

Gerald Alvin Peterson

The dynamic properties of the atomic nucleus depend strongly on correlations between the nucleons. We present a combined analysis of inelastic electron-scattering data and electron-induced proton knockout measurements in an effort to obtain phenomenological information on nucleon-nucleon correlations. Our results indicate that the ratio of radial wave functions extracted from precise 10B(e,e′) and 10B(e,e′p) measurements evolve from an interior depression for small Em, characteristic of short-range correlations, to a surface-peaked enhancement for larger Em, characteristic of long-range correlations. This observation can be interpreted in terms of the nucleon effective mass.

Isolation And Structure Of Sc2@C74, Harry Dorn, Steven Stevenson, Paul Burbank, Kim Harich, Z. Sun, T. Glass, Mark Anderson, Donald Bethune, M. Sherwood

Mark R. Anderson

No abstract is currently available.

29. Motowo Takayanagi, Otto Vogl, Tisoro Kajiyama

Otto Vogl

No abstract provided.

Satellite Studies Of Mid- And Low-Latitude Ionospheric Disturbancezonal Plasma Drifts, L. Scherliess, Bela G. Fejer

Bela G. Fejer

We use low- and mid-latitude zonal ion drift observations from the DE-2 satellite and auroral electrojet indices to study the temporal and latitudinal variations of F-region perturbation drifts during magnetically disturbed conditions. These perturbation drifts are driven by magnetospheric and ionospheric disturbance dynamo electric fields with time constants from less than one to several hours. We determine, initially, the drift patterns due to the prompt penetration of magnetospheric electric fields and of longer lasting disturbances. In this study, we concentrate on the properties of the longer lasting perturbations which occur with latitude-dependent time delays after enhancements in the high-latitude ionospheric …

Quantum-Statistical Properties Of Two Coupled Modes Of Electromagnetic Field, Serguei Y. Kalmykov, Mikhail E. Veisman

Serge Youri Kalmykov

Squeezing the quantum fluctuations of the two-mode light due to the nonstationary coupling between the quadrature components q_1 and q_2 is examined. The delta-function and step-function mode couplings are considered. The conditions of weak and strong step-function coupling are distinguished, the latter being the condition of the instability for the classical counterpart of the quantum system under study. Under the conditions of weak coupling the quadrature squeezing is established in both a two-mode electromagnetic noise in thermal equilibrium (the thermal state) and a two- mode correlated coherent state (CCS). Squeezing in the thermal state is suppressed at a high temperature. …

Annual And Daily Meteorological Cycles At High Altitude On A Tropical Mountain, Douglas R. Hardy, Mathias Vuille, Carsten Braun, Frank Keimig, Raymond S. Bradley

Raymond S Bradley

An automated weather station was installed in October 1996 at the summit of Nevado Sajama, located in the western Andean Cordillera of Bolivia (6542 m, 18°06¢S, 68°53¢W). Meteorological conditions on the mountain are being observed to improve the calibration of geochemical variations within tropical ice cores. This article documents the design and operation of the station and presents a discussion of measurements made through the first annual cycle. Variables analyzed include pressure, incoming solar radiation, air temperature, humidity, wind, and snow accumulation. Large diurnal fluctuations were recorded in most variables, which is not unexpected given the location at 18°S; the …

Spectroscopic Probes Of Bonded Interfaces, Mark Anderson, C. Douglas Taylor, Cynthia Kraft

Mark R. Anderson

No abstract is currently available.

The Electrochemistry Of Fullerenes And Metallofullerenes, Mark Anderson

Mark R. Anderson

No abstract is available at this time.

Friction Anisotropy And Asymmetry Of A Compliant Monolayer Induced By A Small Molecular Tilt, Nancy Burnham, M Liley, D. Gourdon, Dimitrios Stamou, U Meseth, T Fischer, C Lautz, H Stahlberg, H Vogel, C Duschl

Nancy A. Burnham

Lateral force microscopy in the wearless regime was used to study the friction behavior of a lipid monolayer on mica. In the monolayer, condensed domains with long-range orientational order of the lipid molecules were present. The domains revealed unexpectedly strong friction anisotropies and non-negligible friction asymmetries. The angular dependency of these effects correlated well with the tilt direction of the alkyl chains of the monolayer, as determined by electron diffraction and Brewster angle microscopy. The molecular tilt causing these frictional effects was less than 15 degrees, demonstrating that even small molecular tilts can make a major contribution to friction.

Studies Of Molecular Priming For Adhesive Interactions, C, Douglas Taylor, Mark Anderson

Mark R. Anderson

No abstract is currently available.

Predicting Future Years Of Healthy Life For Older Adults, Paula Diehr

Paula Diehr

Cost-effectiveness studies often need to compare the cost of a program to the lifetime benefits of the program, but estimates of lifetime benefits are not routinely available, especially for older adults. We used data from two large longitudinal studies of older adults (ages 65-100) to estimate transition probabilities from one health state to another, and used those probabilities to estimate the mean additional years of healthy life that an older adult of specified age, sex, and health status would experience. We found, for example, that 65-year-old women in excellent health can expect 16.8 years of healthy life in the future, …

30. Manfred Raetzsch, Otto Vogl

Otto Vogl

No abstract provided.