Elastic and inelastic scattering of electrons by Na
Explore the source record for details and available documents.
Srivastava, S. K.↗
SEARCH · Search NASA
Results for “Inelastic”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
An analysis of information design and packaging for an inelastic market
Producers of technical reports can increase the potential use of the technical report, as an information product, by making certain changes to the sequential, language, and presentation components. These improvements, which effect the overall design and packaging of the product, are discussed. These improvements are likely to have their greatest impact on the marginal technical report user. However, these improvements are not without economic consideration. For this reason, cost factors should be calculated to ensure that benefits to the user and/or increased utility will outweight the cost to the producer.
Pinelli, T. E.↗
Level shifts and inelastic electron scattering in dense plasmas
A completely quantum mechanical formalism has been developed to describe the high density plasma effects on fundamental atomic parameters. Both the bound and free electrons are treated by a method which in principle is similar to Hartree's self-consistent field method. The free plasma electrons' wavefunction is obtained from the Schroedinger equation with the effective potential representing the spherically averaged Coulomb interaction with bound and free electrons. Results are given for level shifts, coefficients of transition probabilities, and electron collision cross sections of Ne(9+) for temperatures of 200 and 500 eV for an electron density range of 1-6 x 10 to the 24th per cu cm.
Davis, J.↗
Path-independent integrals in finite elasticity and inelasticity, with body forces, inertia, and arbitrary crack-face conditions
(Previously announced in STAR as N81-32547)
Atluri, S. N.↗
A Potential Function Derivation of a Constitutive Equation for Inelastic Material Response
Physical and thermodynamic concepts are used to develop a potential function for application to high temperature polycrystalline material response. Inherent in the formulation is a differential relationship between the potential function and constitutive equation in terms of the state variables. Integration of the differential relationship produces a state variable evolution equation that requires specification of the initial value of the state variable and its time derivative. It is shown that the initial loading rate, which is directly related to the initial hardening rate, can significantly influence subsequent material response. This effect is consistent with observed material behavior on the macroscopic and microscopic levels, and may explain the wide scatter in response often found in creep testing.
Stouffer, D. C.↗
Elastic and inelastic electron scattering by rubidium at 10, 20 and 200 eV impact energies
Explore the source record for details and available documents.
Vuskovic, L.↗
On a possibility of inelasticity partial coefficient K sub gamma determination in pi C and pi Pb interactions at 10 to the 14th power eV (experiment PAMIR 1)
The investigation of hadron-nuclear interactions in Pamir experiment is carried out by means of X-ray emulsion chambers of two types: carbon (C) and lead (Pb). While comparing the results from the chambers of both types it was found a discrepancy in n sub h and E sub h(1)R values. The observed discrepancy in C and Pb chambers is connected with the difference in values of effective coefficients of energy transfer to the soft component K sub eff for C and Pb chambers.
Borisov, A. S.↗
Few-particles generation channels in inelastic hadron-nuclear interactions at energy approximately equals 400 GeV
The behavior of the few-particles generation channels in interaction of hadrons with nuclei of CH2, Al, Cu and Pb at mean energy 400 GeV was investigated. The values of coherent production cross-sections beta coh at the investigated nuclei are given. A dependence of coherent and noncoherent events is investigated. The results are compared with the simulations on additive quark model (AQM).
Tsomaya, P. V.↗
Rotational inelastic cross sections for OCS-Ar, OCS-He, OCS-H2 collisions - A comparison between theory and experiment
The experimental determination of absorption line profiles for OCS nu3 vibrational transitions broadened by collisions with Ar, He, and H3 buffer gases is reported. The experimental method using diode laser spectroscopy in the five micron region is described. The data are compared with theoretical values obtained using intermolecular potentials previously suggested for these systems and infinite order sudden approximation molecular scattering calculations.
Broquier, M.↗
A Constitutive Model for the Inelastic Multiaxial Cyclic Response of a Nickel Base Superalloy Rene 80
The objective was to develop unified constitutive equations which can model a variety of nonlinear material phenomena observed in Rene 80 at elevated temperatures. A constitutive model was developed based on back stress and drag stress. The tensorial back stress was used to model directional effects; whereas, the scalar drag stress was used to model isotropic effects and cyclic hardening or softening. A flow equation and evolution equations for the state variables were developed in multiaxial form. Procedures were developed to generate the material parameters. The model predicted very well the monotonic tensile, cyclic, creep, and stress relaxation behavior of Rene 80 at 982 C. The model was then extended to 871, 760, and 538 C. It was shown that strain rate dependent behavior at high temperatures and strain rate independent behavior at the lower temperatures could be predicted very well. A large number of monotonic tensile, creep, stress relation, and cyclic experiments were predicted. The multiaxial capabilities of the model were verified extensively for combined tension/torsion experiments. The prediction of the model agreed very well for proportional, nonproportional, and pure shear cyclic loading conditions at 982 and 871 C.
Ramaswamy, V. G.↗
The temperature dependence of inelastic light scattering from small particles for use in combustion diagnostic instrumentation
A computer calculation of the expected angular distribution of coherent anti-Stokes Raman scattering (CARS) from micrometer size polystyrene spheres based on a Mie-type model, and a pilot experiment to test the feasibility of measuring CARS angular distributions from micrometer size polystyrene spheres by simply suspending them in water are discussed. The computer calculations predict a very interesting structure in the angular distributions that depends strongly on the size and relative refractive index of the spheres.
Cloud, Stanley D.↗
Three-dimensional inelastic approximate analysis code (MOMM)
The Mechanics of Materials Model (MOMM) is one of a series of new stand-alone three dimensional nonlinear structural analysis codes. Incorporation of a general purpose finite element computer code into the hot section design process was severely limited by the high costs involved. MOMM is a stiffness method finite element code that uses an internally generated network of beams to characterize hot section component behavior. The method was proposed as a fast, easy to use, computationally efficient tool for approximate analyses. MOMM incorporates a wide variety of analysis capabilities, material models, and load type specifiers instrumental for the analysis of hot section components.
Meister, Jeffrey P.↗
Response characteristics of MHOST (MARC Hot-Section Technology) for 3-D inelastic analysis of hot-section components
The advantages of a newly developed code are demonstrated by comparisons of the analysis with existing theoretical data as well as with other available finite element programs. The new program shows promise to significantly reduce the computer time. It also permits accurate and efficient structural analysis of engine hot section components.
Shen, Lawrence K.↗
Inelastic scattering of positrons with sodium
The two potential approach is used to study the resonant 3s-3p excitation of sodium atom by positrons of energy 40 and 54.4eV. The angular variation of coherence and correlation parameters is presented. Comparison with the corresponding parameters in electron scattering is given to see the role of various interaction potentials in electron and positron scattering.
Purohit, S. P.↗
High temperature inelastic deformation of the B1900 + Hf alloy under multiaxial loading - Theory and experiment
The multiaxial deformation behavior of the Ni-based alloy B1900 + Hf has been studied at elevated temperatures in the range of 649-982 C. Combined tension/torsion cyclic tests were performed on thin-wall tubular specimens under both in-phase and out-of-phase strain-controlled loading cycles. Both straining conditions resulted in stress loci of comparable magnitude, exhibiting no difference in cyclic hardening response. A phase angle was observed between the deviatoric stress and the incremental plastic strain vectors during 90-deg out-of-phase strain cycling, and nonproportional stress relaxation occurred under biaxial strain hold. The overall results have been used to assess the flow law, the hardening equations, and the applicability of the J2-based, elastic-viscoplastic model of Bodner-Partom (1979) for multiaxial loading conditions. The overall agreement between theory and experiment is good. Discrepancies are discussed in relation to micromechanical considerations.
Chan, K. S.↗
Advanced applications of BEM to inelastic analysis of solids
Newly evolved boundary element solution algorithms are utilized for solving a range of elastoplastic and thermoplastic problems. The first algorithm is the typical iterative procedure in which the unknown boundary solution and the initial stress (or strain) rates are found together in an incremental iterative fashion. The second one is a variable stiffness type approach in which the incremental boundary solution is obtained in a direct (noniterative) manner. The third procedure differs from the two prior algorithms in that volume integration is not needed to incorporate the nonlinear effects in the analysis. Instead, initial stress rates are introduced in the boundary element system by way of particular integrals. The methodology is used in a general purpose, multiregion system that employs quadratic isoparametric shape functions to model the geometry and field variables of the body and can admit up to 15 substructured areas of different material properties.
Banerjee, P. K.↗
The MHOST finite element program: 3-D inelastic analysis methods for hot section components. Volume 1: Theoretical manual
Formulations and algorithms implemented in the MHOST finite element program are discussed. The code uses a novel concept of the mixed iterative solution technique for the efficient 3-D computations of turbine engine hot section components. The general framework of variational formulation and solution algorithms are discussed which were derived from the mixed three field Hu-Washizu principle. This formulation enables the use of nodal interpolation for coordinates, displacements, strains, and stresses. Algorithmic description of the mixed iterative method includes variations for the quasi static, transient dynamic and buckling analyses. The global-local analysis procedure referred to as the subelement refinement is developed in the framework of the mixed iterative solution, of which the detail is presented. The numerically integrated isoparametric elements implemented in the framework is discussed. Methods to filter certain parts of strain and project the element discontinuous quantities to the nodes are developed for a family of linear elements. Integration algorithms are described for linear and nonlinear equations included in MHOST program.
Nakazawa, Shohei↗
A constitutive model for the high temperature inelastic response of nickel base superalloys
The objective of this research is to develop a constitutive equation for the uniaxial and multiaxial fatigue response of Rene 80 between the temperatures of 538 C and 982 C. The constitutive equation is accompanied by an experimental program for the evaluation of the material constants and extensive verification through the successful prediction of mechanical cycling experiments. These results include the prediction of the high temperature multiaxial response of Rene 80 that includes torsion and proportional and non-proportional loading histories.
Stouffer, D. C.↗