2 resultados para Brownian movements.
em Digital Commons - Michigan Tech
Resumo:
Historical accounts of revolutionary movements oftentimes occlude the pleasures of countering hegemony or criticize the “frivolity” of what is perceived to be non-political activities. However, turn of the century Finnish-American socialist theater clubs and early twentieth century Finnish-American communist halls and their uncounted social groups and activities prove to be a rich resource in reconsidering the importance of acknowledging and understanding the role that pleasure has played and should play in political protest. Finnish-American radical activities, especially those condemned already at the time as hall socialism, are important historical precedents to today’s alter-globalization student festivals and protest concerts, midnight raves
Resumo:
This study develops an automated analysis tool by combining total internal reflection fluorescence microscopy (TIRFM), an evanescent wave microscopic imaging technique to capture time-sequential images and the corresponding image processing Matlab code to identify movements of single individual particles. The developed code will enable us to examine two dimensional hindered tangential Brownian motion of nanoparticles with a sub-pixel resolution (nanoscale). The measured mean square displacements of nanoparticles are compared with theoretical predictions to estimate particle diameters and fluid viscosity using a nonlinear regression technique. These estimated values will be confirmed by the diameters and viscosities given by manufacturers to validate this analysis tool. Nano-particles used in these experiments are yellow-green polystyrene fluorescent nanospheres (200 nm, 500 nm and 1000 nm in diameter (nominal); 505 nm excitation and 515 nm emission wavelengths). Solutions used in this experiment are de-ionized (DI) water, 10% d-glucose and 10% glycerol. Mean square displacements obtained near the surface shows significant deviation from theoretical predictions which are attributed to DLVO forces in the region but it conforms to theoretical predictions after ~125 nm onwards. The proposed automation analysis tool will be powerfully employed in the bio-application fields needed for examination of single protein (DNA and/or vesicle) tracking, drug delivery, and cyto-toxicity unlike the traditional measurement techniques that require fixing the cells. Furthermore, this tool can be also usefully applied for the microfluidic areas of non-invasive thermometry, particle tracking velocimetry (PTV), and non-invasive viscometry.