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Full-Text Articles in Physics
Laboratory Experiments Of Entrainment In Dry Convective Boundary Layers, Harm J.J. Jonker, Thijs Heus, Esther Hagen, Han Van Dop
Laboratory Experiments Of Entrainment In Dry Convective Boundary Layers, Harm J.J. Jonker, Thijs Heus, Esther Hagen, Han Van Dop
Physics Faculty Publications
Entrainment in dry convective boundary layers was studied. A saline convection tank set-up was used as a laboratory model for a dry convective atmospheric boundary layer. The entrainment flux was measured using planar laser induced fluorescence (PLIF). It was found that the entrainment flux reveals a much stronger dependence on the inversion strength than large eddy simulations tend to do.
Calculation Of The Radiation Trapping Force For Laser Tweezers By Use Of Generalized Lorenz-Mie Theory. Ii. On-Axis Trapping Force, James A. Lock
Calculation Of The Radiation Trapping Force For Laser Tweezers By Use Of Generalized Lorenz-Mie Theory. Ii. On-Axis Trapping Force, James A. Lock
Physics Faculty Publications
The efficiency of trapping an on-axis spherical particle by use of laser tweezers for a particle size from the Rayleigh limit to the ray optics limit is calculated from generalized Lorenz-Mie light-scattering theory and the localized version of a Gaussian beam that has been truncated and focused by a high-numericalaperture lens and that possesses spherical aberration as a result of its transmission through the wall of the sample cell. The results are compared with both the experimental trapping efficiency and the theoretical efficiency obtained from use of the localized version of a freely propagating focused Gaussian beam. The predicted trapping …
Calculation Of The Radiation Trapping Force For Laser Tweezers By Use Of Generalized Lorenz-Mie Theory. I. Localized Model Description Of An On-Axis Tightly Focused Laser Beam With Spherical Aberration, James A. Lock
Physics Faculty Publications
Calculation of the radiation trapping force in laser tweezers by use of generalized Lorenz-Mie theory requires knowledge of the shape coefficients of the incident laser beam. The localized version of these coefficients has been developed and justified only for a moderately focused Gaussian beam polarized in the x direction and traveling in the positive z direction. Here the localized model is extended to a beam tightly focused and truncated by a high-numerical-aperture lens, aberrated by its transmission through the wall of the sample cell, and incident upon a spherical particle whose center is on the beam axis. We also consider …
Variable-Temperature Scanning Optical And Force Microscope, Petru S. Fodor, H. Zhu, N. G. Patil, J. Levy
Variable-Temperature Scanning Optical And Force Microscope, Petru S. Fodor, H. Zhu, N. G. Patil, J. Levy
Physics Faculty Publications
The implementation of a scanning microscope capable of working in confocal, atomic force and apertureless near field configurations is presented. The microscope is designed to operate in the temperature range 4–300 K, using conventional helium flow cryostats. In atomic force microscope(AFM) mode, the distance between the sample and an etchedtungsten tip is controlled by a self-sensing piezoelectrictuning fork. The vertical position of both the AFM head and microscope objective can be accurately controlled using piezoelectric coarse approach motors. The scanning is performed using a compact XYZ stage, while the AFM and optical head are kept fixed, allowing scanning probe and …
Age Differences In Central (Semantic) And Peripheral Processing: The Importance Of Considering Both Response Times And Errors, Philip A. Allen, Martin D. Murphy, Miron Kaufman, Karen E. Groth, Ana Begovic
Age Differences In Central (Semantic) And Peripheral Processing: The Importance Of Considering Both Response Times And Errors, Philip A. Allen, Martin D. Murphy, Miron Kaufman, Karen E. Groth, Ana Begovic
Physics Faculty Publications
In this project we examined the effect of adult age on visual word recognition by using combined reaction time (RT) and accuracy methods based on the Hick–Hyman law. This was necessary because separate Brinley analyses of RT and errors resulted in contradicting results. We report the results of a lexical decision task experiment (with 96 younger adults and 97 older adults). We transformed the error data into entropy and then predicted RT by using entropy values separately for exposure duration (thought to influence peripheral processes) and word frequency (thought to influence central processes). For exposure duration, the entropy–RT functions indicate …