The classic approach to preparation of XRF specimens of inhomogeneous materials is the method of flux/fusion. This technique has not been applied to automotive catalysts because they utilize large quantities of precious metals (Pt, Pd, Rh) that are reduced at typical fusion temperatures and agglomerate and alloy with the crucible walls, leading to erratic losses of the precious metals. This eff...

The settling and packing properties of colloidal suspensions of large hard spheres in an effective gravitational field are investigated by a Monte Carlo constant-NPV simulation. The ratio of an effective gravitational potential to the repulsion/attraction potential in the hard sphere (G/ε) is a critical parameter that determines the surface coverage and packing properties of the system. The sur...

Porous structure of reduced graphene oxide (rGO) plays an important role in developing flexible graphene-based devices. In this work, we report a novel methodology for reduction of freestanding graphite oxide (GO) sheet by picosecond pulse laser direct writing in liquid nitrogen. Non-agglomerate and porous structure of rGO is fabricated successfully due to frozen effect during laser processing....

Fine powders often tend to agglomerate due to van der Waals forces between the particles. These forces can be reduced significantly by covering the particles with nanoscaled adsorbates, as shown by recent experiments. In the present work a quantitative statistical analysis of the effect of powder flow regulating nanomaterials on the adhesive forces in powders is given. Covering two spherical po...

Bile salts are ionic amphiphilic compounds with a steroid skeleton. Among the most important physiological properties of bile salts are lipid transport by solubilization and transport of some drugs through hydrophobic barriers. Bile salts have been extensively studied to enhance transepithelial permeability for different marker molecules and drugs. They readily agglomerate at concentrations abo...

The program STRUCTNRA for the simulation of ion beam analysis charged particle spectra from arbitrary two-dimensional distributions of materials is described. The code is validated by comparison to experimental backscattering data from a silicon grating on tantalum at di erent orientations and incident angles. Simulated spectra for several types of rough thin layers and a chessboard-like arrang...