in this paper, size distribution of nano-bubbles was measured by the reliable and fast method of laserdiffraction technique. nano-bubbles were produced using a nano-bubble generator designed and madebased on hydrodynamic cavitation phenomenon in venturi tubes. a central composite design withresponse surface methodology was used to conduct a five factor, five level factorial experimental designo...

This paper describes a laser diffraction particle stzing technique applications and hardware improvements. With sound theoretical background, this technique finds itself competing in the particle sizing technology market with the introduction of Malvern model series 1800, 2600 and Master Sizer of which the first two models have been tested extensively. Correction schemes to overcome same basic ...

Sedimentation has been a standard methodology for particle size analysis since the early 1900s. In recent years laser diffraction is beginning to replace sedimentation as the prefered technique in some industries, such as marine sediment analysis. However, for the particle size analysis of soils, which have a diverse range of both particle size and shape, laser diffraction still requires evalua...

The subtle changes in the physiology of erythrocytes at the cellular level on documented in the present laser diffraction study. Using this technique one can differentiate the morphologies of erythrocytes. The size and shape of blood cells are determined usually by microscope. This method, besides being tedious, cannot be extended to a large number of cells and samples. In view of this, a simpl...

We report sub-diffraction resolution in two-photon excitation (TPE) fluorescence microscopy achieved by merging this technique with stimulated-emission depletion (STED). We demonstrate an easy-to-implement and promising laser combination based on a short-pulse laser source for two-photon excitation and a continuous-wave (CW) laser source for resolution enhancement. Images of fluorescent nanopar...

Northrop Grumman reports on a program utilizing Linear Phase Conjugation to compensate for atmospheric induced aberrations that severely limit laser performance. In a program to improve both the beam quality and laser energy delivered to the target, Northrop Grumman has developed a novel aberration compensation technique. This technique, hereafter referred to as Active Tracking System, utilizes...

Laser direct-write patterning methods are traditionally limited by the diffraction limit to size scales several hundreds of nanometers at the minimum. In this work, we demonstrate a new method of laser based patterning that overcomes these limitations by taking advantage of near-field enhancement at the surface of dielectric microspheres. Polystyrene microspheres are trapped in CW Bessel beam l...

New developments on laser heated diamond anvil cell are reported by introducing a system installed at the Advanced Photon Source (APS). With the system, a laser heating spot of 20 40 μm in diameter can be generated to temperatures over 3000 K for samples in diamond anvil cell; and the temperature gradients in the laser heated volume are less than 100 K. The system is based on the double sided l...

In the present study, an ultrafine grained (UFG) 304L stainless steel with the average grain size of 300 nm was produced by a combination of cold rolling and annealing. Weldability of the UFG sample was studied by Nd: YAG laser welding under different welding conditions. Taguchi experimental design was used to optimize the effect of frequency, welding time, laser current and laser pulse duratio...