St. John's Daily Star, 1919-06-02

The St. John's Daily Star was published daily except Sunday between 17 April 1915 - 23 July 1921

Small angle x-ray scattering with a beryllium compound refractive lens as focusing optic

At BW4 at HASYLAB a beryllium compound refractive lensBe-CRLis used for the focusing insmall-angle x-ray scattering experiments. Using it provides the advantages of higher long-termstability and a much easier alignment compared to a setup with focusing mirrors. In ourinvestigations presented here, we show the advantages of using a Be-CRL in small-angle and alsoultra small-angle x-ray scattering. We investigated the beam characteristics at the sample positionwith respect to spot size and photon flux. The spot size is comparable to that of a setup with focusingmirrors but with a gain in flux and better long-term stability. It is also shown that plane mirrors arestill necessary to suppress higher order energies passing the monochromator

Preparation and Electrical Properties of Cobalt-Platinum Nanoparticle Monolayers Deposited by the Langmuir-Blodgett Technique

The Langmuir-Blodgett technique was utilized and optimized to produce closed monolayers of cobalt-platinum nanoparticles over vast areas. It is shown that sample preparation, "dipping angle", and subphase type have a strong impact on the quality of the produced films. The amount of ligands on the nanoparticles surface must be minimized, the dipping angle must be around 105$^{\circ}$, while the glycol subphase is necessary to obtain nanoparticle monolayers. The achieved films were characterized by scanning electron microscopy (SEM) and grazing incidence x-ray scattering (GISAXS). The electrical properties of the deposited films were studied by direct current (DC) measurements showing a discrepancy to the variable range hopping transport from the granular metal model, and favoring the simple thermal activated charge transport. SEM, GISAXS as well as DC measurements confirm a narrow size distribution and high ordering of the deposited films.Comment: 8 pages, 6 figure