Bremsstrahlung of 350--450 MeV protons as a tool to study NNNN interaction off-shell

The $pp\to pp\gamma$ bremsstrahlung cross section is calculated within the method of coordinate space representation. It is shown that in the beam energy range of 350--450~MeV a deep attractive NN-potential with forbidden states (Moscow potential) and realistic meson exchange potentials (MEP) give rise to the cross sections that differ essentially in shape: the cross sections nearly coincide in the minima but differ by a factor of 5 approximately in the maxima. Therefore, the $pp\to pp\gamma$ reaction at energies $\sim$350--450~Mev can be used to study $NN$ interaction off-shell and to discriminate experimentally between MEP and Moscow potential.Comment: 5 pages, latex, 4 PS figures. Talk presented by Andrey Shirokov at the International Conference on Quark Lepton Nuclear Physics ``QULEN97'', May 20-23, 1997, Osaka, Japan; to be published in Nucl. Phys.

Thermal energy storage

The general scope of study on thermal energy storage development includes: (1) survey and review possible concepts for storing thermal energy; (2) evaluate the potentials of the surveyed concepts for practical applications in the low and high temperature ranges for thermal control and storage, with particular emphasis on the low temperature range, and designate the most promising concepts; and (3) determine the nature of further studies required to expeditiously convert the most promising concept(s) to practical applications. Cryogenic temperature control by means of energy storage materials was also included

Improved catalysts by low-G processing

The advantages of space for manufacturing more perfect microcrystalline morphologies and structures will be investigated. Production of smaller silver and palladium crystals with enhanced catalytic properties is discussed. The elimination of convection accompanying electrodeposition of fine metallic powders at high overvoltages in a low gravity environment is outlined

Calorimetric Measurements on High Purity Iron and Eutectoid Steels

Plan of the Investigation: The data needed to determine the thermodynamics of the transformation of a steel are: (1) the specific heat of austenite from above the critical temperature to the transformation temperature, (2) the specific heat of the transformed product from the reaction temperature to room temperature, (3) the enthalpy change at the transformation temperature, and (4) the variation of these with temperature of reaction. Since the calorimeter could not be used to determine these data directly, that is, during the transformation of austenite to pearlite at temperatures well below the critical temperature, the problem was approached from the reverse transformation. The specific heat of the pearlite and austenite are known throughout the temperature range over which the transformations are to be studied, and the enthalpy of transformation of pearlite to austenite is known at one temperature, then the thermodynamics of the reaction of austenite to pearlite may be calculated as a function of temperature. In order to determine the effect of the variation of the reaction temperature on the transformation of austenite to pearlite, specimens of known alloy content were completely transformed at various subcritical temperatures, for times just long enough to complete the transformation. These were run in the calorimeter to determine the specific heat of the pearlite from room temperature to the reaction temperature, pearlite to austenite, the enthalpy of transformation of pearlite to austenite, and the specific heat of austenite from the reaction temperature to approximately 900°C. Any differences in the specific heat of the pearlite to the reaction temperature would be due to differences in inerlamellar spacing, to any partitioning of the alloying element between ferrite and cementite in the pearlite, and to inherent differences in the pearlite itself since pearlite of the same physical structure reacted at a higher temperature. Any differences in the enthalpy of transformation of pearlite to austenite would be due to the differnces in the partitioning of the alloying element, in the interlamellar spacing, and possibly due to energy state of the pearlite. By comparison of the specific heats and the enthalpies of transformation of the specimens that had been treated to different conditions, the effect of each of the possible variables and conditions could then be determined. Since the kinetic data for a high purity 0.75% C-1% Mn steel (15) had been determined and the specimens of the proper size and shape had been transformed to 100% pearlite at several subcritical temperatures for this investigation, the primary object of this investigation was a determination of the thermodynamics of this steel. In order to help evaluate the effect of the addition of the manganese as an alloying element, specimens of high purity iron, carburized to eutectoid carbon content were to be isothermally transformed at the same subcritical temperatures and the thermodynamics of this alloy determined. Also, a specimen of high purity electrolytic iron was to be run to determine the specific heat for comparison with the alloy steels. The enthalpy of transformation of iron was to be determined to provide a check for the self consistency of the data for the steels and to compare with the values for the specific heat and enthalpy of transformation reported in the literature since a fairly wide scatter exists in the reported values. From the above specimens it would be possible also, by knowing the interlamellar spacing of the pearlite for each specimen, to determine the interfacial energy of the interface between ferrite and cementite and the effect of the alloying element on the interfacial energy. By running hyper- and hypo- eutectoid steels in the calorimeter, and comparing to the eutectoid alloys, the heat of solution of ferrite and cementite in austenite could be determined

Gender role stereotypes in advertising : a test of the match-up hypothesis on advertising effectiveness.

Images in advertisements often depict social expectations for gendered behavior, reinforcing stereotypical masculine and feminine behaviors. This study examined the effectiveness of using gender role stereotypical images in advertisements by matching two products with a male and female, based on the match-up hypothesis. Two gender congruent and two gender incongruent advertisements were created to test the effectiveness of gender congruency on perceived message clarity, advertisement believability, perceived argument quality, attitude toward the advertisement, attitude toward the brand, and purchase intention, based on the information-processing model. Though gender congruent advertisements were perceived as slightly more effective than the gender incongruent advertisements, perceived message clarity was the only variable significantly influenced by gender congruency as messages in gender congruent advertisements were perceived as more clear than those in gender incongruent advertisements. Therefore, this study serves to encourage advertisers to re-evaluate current advertising techniques, as they are currently reinforcing gender stereotypical behaviors for little benefit

Study of relativistic bound state wave functions in quasielastic (e,e'p) reactions

The unpolarized response functions of the quasielastic $^{16}O(e,e^\prime p)^{15}N$ reaction are calculated for three different types of relativistic bound state wave functions. The wave functions are obtained from relativistic Hartree, relativistic Hartree-Fock and density dependent relativistic Hartree calculations that reproduce the experimental charge radius of $^{16}$O. The sensitivity of the unpolarized response functions to the single particle structure of the different models is investigated in the relativistic plane wave impulse approximation. Redistributions of the momentum dependence in the longitudinal and transverse response function can be related to the binding energy of the single particle states. The interference responses $R_{LT}$ and $R_{TT}$ reveal a strong sensitivity to the small component of the relativistic bound state wave function.Comment: 18 pages REVTEX, 5 figures include

Droplet Dynamics in Cooling Tower Plumes

Large cooling towers are becoming more common as a means of disposing of large quantities of waste heat from steam electric generating stations. Increased attention is being focused on how the effluents from these towers affect the environment. This research is concerned with the determination of the paths and ultimate deposition of salt laden drift drops exiting from a cooling tower by analyzing the basic droplet dynamics governing the transport of these droplets. The equation of motion is developed for a liquid drift drop as it is transported through the atmosphere. A term appears in the equation of motion which has not been considered by previous authors. A finite difference technique is used to solve for the velocity and position of the drift drop at any time. Meteorological variables as well as cooling tower variables are considered in calculating the trajectory of the drift drop. A model is developed to account for the effects of dissolved chemicals on droplet evaporation rate. The concepts presented in this paper have been incorporated into a model which predicts chemical deposition from evaporative cooling towers. The results of the model study show better agreement with experimental data than previous models

A Study of the Δ−\Delta^--component of the wave-function in light nuclei

We have measured cross sections for the $(\pi^+,\pi^\pm p)$ reactions on ${\rm ^3H}$, ${\rm ^4He}$, ${\rm ^6Li}$ and ${\rm ^7Li}$ in quasi-free kinematics at incident pion beam energy 500 MeV. An enhancement of the $(\pi^+,\pi^- p)$ cross section in this kinematics is observed. If this is interpreted as due to quasi-free scattering from pre-existing $\Delta$ components of the nuclear wave function, the extracted probabilities are in agreement with theoretical expectations.Comment: 3 pages, 3 figures, 1 tabl

Medium-Energy Proton-Nucleus Elastic Scattering in the Impulse Approximation

This work was supported by National Science Foundation Grants PHY 76-84033A01, PHY 78-22774, and Indiana Universit

Total Cross Sections for Neutron Scattering

Measurements of neutron total cross-sections are both extensive and extremely accurate. Although they place a strong constraint on theoretically constructed models, there are relatively few comparisons of predictions with experiment. The total cross-sections for neutron scattering from $^{16}$O and $^{40}$Ca are calculated as a function of energy from $50-700$~MeV laboratory energy with a microscopic first order optical potential derived within the framework of the Watson expansion. Although these results are already in qualitative agreement with the data, the inclusion of medium corrections to the propagator is essential to correctly predict the energy dependence given by the experiment.Comment: 10 pages (Revtex 3.0), 6 fig