The photostimulated desorption yield of neutral halogen atoms from KI, KBr, and RbI at several temperatures has been measured in the photon energy range between 5 and 30 eV using synchrotron radiation and quadrupole mass spectrometry. The features observed in the desorption yield are slightly correlated with the structures of the absorption spectra of each investigated material. The behavior of...

This article summarizes the 13th ICFA Beam Dynamics Mini-Workshop Beam-Induced Pressure Rise in Rings (BNL, Dec. 9-12, 2003) [1]. BACKGROUND OF WORKSHOP Beam induced pressure rise was an intensity limit at CERN ISR during the early 1970's. The beam gas ionization created pressure rise caused more gas ionization, resulting in pressure run-away at high beam intensity. Extensive baking, chamber tr...

cobalt chromite (cocr2o4) with normal spinel structure, shows catalytic activity for oxidation of unburned methane in the natural gas vehilcles (ngv). in this study, cocr2o4 nanoparticles were synthesized through a conventional co-precipitation technique and investigated for the catalytic combustion of methane. cobalt nitrate hexahydrate, chromium nitrate nonahydrate and ammonia solution (25%) ...

Thin films of the short single DNA strand, GCAT, in which one of the bases has been removed were bombarded with 3 to 15 eV electrons. The yield functions of the H(-), O(-) and OH(-) ions desorbed from these films exhibit a broad peak near 9 eV, which is attributed to dissociative electron attachment to the basic molecules. Whereas removal of any one of the bases considerably decreases N-glycosi...

We investigated the reaction mechanism of the desorption of single hydrogen from a titanium dioxide surface excited by the tip of a scanning tunneling microscope (STM). Analysis of the desorption yield, in combination with theoretical calculations, indicates the crucial role played by the applied electric field. Instead of facilitating desorption by reducing the barrier height, the applied elec...

this paper presents a systematic study of the surface chemistry, porous texture and adsorptive characteristics of prepared new activated carbon using persian mesquite grain. several techniques and methodologies such as, proximate analysis, n2 adsorption–desorption isotherms, scanning electron microscope (sem), fourier transform infrared spectroscopy(ft-ir), x-ray diffraction (xrd), x-ray photoe...

Particle accelerators with superconducting magnets operating at cryogenic temperatures use a beam screen (BS) liner that extracts heat generated by the circulating bunched charge particle before it can reach magnets. The BS surface, commonly made of high–conductivity copper, provides low impedance for stability reasons, secondary electron yield (SEY) to mitigate electron–cloud (EC) effect, and ...