Effect of Aqueous HCl with Dissolved Chlorine on Certain Corrosion-Resistant Polymers.

Polypropylene, poly(ethylene terephthalate), ethylene chloro tetrafluoroethylene, ethylene tetrafluoroethylene, and epoxy vinyl ester resin (Derakane 470-300) were evaluated in aqueous HCl containing chlorine gas at high temperature as a corrosion media. Fourier transform infrared, X-ray diffraction, energy-dispersive X-ray, and dynamic mechanical analyzer are used for identification of nature of chemical reactions on polymer chain. Puncture resistance and hardness tests were done to evaluate the mechanical strength after the exposure.

Detachment and reorientation of cells using near-infrared laser microbeam.

Reorientation of adhering cell(s) with respect to other cell(s) has not been yet possible, thus limiting study of controlled interaction between cells. Here, we report cell detachment upon irradiation with a focused near-infrared laser beam, and reorientation of adherent cells. The detached cell was transported along the axial direction by scattering force and trapped at a higher plane inside the media using the same laser beam by a gravito-optical trap.

Trapping and two-photon fluorescence excitation of microscopic objects using ultrafast single-fiber optical tweezers.

Analysis of trapped microscopic objects using fluorescence and Raman spectroscopy is gaining considerable interest. We report on the development of single fiber ultrafast optical tweezers and its use in simultaneous two-photon fluorescence (TPF) excitation of trapped fluorescent microscopic objects. Using this method, trapping depth of a few centimeters was achieved inside a colloidal sample with TPF from the trapped particle being visible to the naked eye.