We have observed that the amount of positronium (Ps) emitted from the surface of p-Si(100) is substantially increased if the sample is irradiated with 532 nm laser light just prior to the implantation of positrons. The energy of the emitted Ps has a constant value of ∼0.16  eV and is independent of the Si temperature and the applied laser fluence, while the photoemission yield depends on both o...

The rapid growth in urban population is seen to create a need for the development of more urban infrastructures. In order to meet this need, natural surfaces such as vegetation are been replaced with non-vegetated surfaces such as asphalt and bricks which has the ability to absorb heat and release it later. This change in land cover is seen to increase the land surface temperature. Previous stu...

in this paper, we examine the effects of thermal radiation on co2 emission and o2 depletion in an exothermic reactive slab of combustible materials with uniform surface temperature. the governing equations for the nonlinear heat and mass transfer problem are derived and solved numerically using runge-kutta-fehlberg method with shooting technique. numerical expressions for temperature field, co2...

The present study deals with stress analysis on orthotropic graded rotating annular discs subjected to temperature distributions parabolically decreasing with radius. I have used infinitesimal deformation theory of elasticity and for graded parameters power law functions in the solution procedure. With the increasing temperature, the tangential stress component decreased at the inner surface wh...

Introduction: There has been considerable interest in the spectral response of the lunar surface near 2.8 and 2.95 μm, where OHand H2O have strong absorptions. Previous studies have identified these absorptions with variable strengths across the lunar surface [1–7]. In particular, the absorptions have been found to be most prominent at higher latitudes and at early and late local times (e.g., [...

abstract land surface hydrological models has importance in the determination of soil moisture and temperature, the rate of evapotranspiration, stream flow by emphasis on the land surface physical and dynamic process descriptions. in this research, vic land surface hydrological model has been used for the land surface temperature and stream flow determination. the vic runoff simulation in each ...

introduction: during the thirty years ago noise pollution increased quickly in the urbane communities that motorcycles are chief sources of noise. the objective of this study is reduction of noise emitted from motorcycle exhaust, applying engineering design. materials and methods: in this pre-experimental study, current condition of noise emitted from motorcycle exhaust and physical parameters ...