Now showing items 1-6 of 6

  • Femtosecond pump probe spectroscopy for the study of energy transfer of light-harvesting complexes from extractions of spinach leaves 

    Ombinda-Lemboumba, S.; Du Plessis, A.; Sparrow, R. W.; Molukanele, P.; Botha, L. R.; Rohwer, E. G.; Steenkamp, C. M.; Van Rensburg, L. (Academy of Science of South Africa (ASSAf), 2009-10)
    Measurements of ultrafast transient processes, of temporal durations in the picosecond and femtosecond regime, are made possible by femtosecond pump probe transient absorption spectroscopy. Such an ultrafast pump probe ...
  • Influence of gas discharge parameters on emissions from a dielectric barrier discharge excited argon excimer lamp 

    Baricholo, Peter; Hlatywayo, Dumisani J.; Von Bergmann, Hubertus M.; Stehmann, Timo; Rohwer, Erick; Collier, Mike (ASSAF -- Academy of Science of South Africa, 2011-11)
    A dielectric barrier discharge excited neutral argon (Ar I) excimer lamp has been developed and characterised. The aim of this study was to develop an excimer lamp operating at atmospheric pressure that can replace mercury ...
  • International astronomer Phil Charles meets the ire of the National Research Foundation 

    Bohm, Lothar (Academy of Science of South Africa (ASSAf), 2010-03)
    Recent weeks have seen an embarrassing display of heavy-handed National Research Foundation (NRF) management in connection with the Square Kilometer Array (SKA) project – a new $2 billion radio astronomy facility to be ...
  • Internet access constrains science development and training at South African universities 

    Slippers, Bernard; Majozi, Thokozani; Nelwamondo, Fulufhelo V.; Steenkamp, Christine M.; Van Heerden, Esta; Wright, Caradee Y. (Academy of Science of South Africa (ASSAf), 2011-09)
    As a group of young scientists whose future careers depend increasingly on access to Internet resources, we are extremely concerned by the apparent lack of understanding of the stranglehold that current approaches to ...
  • Nonperturbative flow equations from running expectation values 

    Scholtz, F. G.; Bartlett, Bruce H.; Geyer, H. B. (American Physical Society (APS), 2003-08)
    We show that Wegner’s flow equations, as recently discussed in the Lipkin model, can be solved selfconsistently. This leads to a nonlinear differential equation which fully determines the order parameter as a function ...
  • White light wavefront control with a spatial light modulator 

    Dirk-Mathys, Spangenberg; Dudley, Angela; Neethling, Pieter H.; Rohwer, Erich G.; Forbes, Andrew (Optical Society of America, 2014-05)
    Spatial light modulators are ubiquitous tools for wavefront control and laser beam shaping but have traditionally been used with monochromatic sources due to the inherent wavelength dependence of the calibration process ...