An investigation was made of various factors, both experimental and physiological, which influenced the formation of hydrogen gas by the heterocystous cyanobacterium Anabaena cylindrica B629 when incubated in both argon and air. A. cylindrica B629 produces hydrogen in air in the presence of carbon monoxide, acetylene, or both, with a short lag period. The rate of production in air at optimal co...

0026-2714/$ see front matter 2010 Elsevier Ltd. A doi:10.1016/j.microrel.2010.02.023 * Corresponding author. E-mail address: [email protected] (A. Peque The development of novel Cu wires for thermosonic wire bonding is time consuming and the effects of shielding gas on the electrical flame off (EFO) process is not fully understood. An online method is used in this study for characterizing C...

A parallelized three-dimensional self-consistent electrostatic particle-in-cell (PIC) code using unstructured tetrahedral mesh is proposed. Parallel implementation of the current unstructured PIC-FEM code is realized on distributedmemory PC-cluster system utilizing dynamic domain decomposition. Completed code is verified by simulating a quasi-1D RF argon gas discharge with results comparable to...

This application note highlights percentage level analysis of hydrogen on an Agilent Micro GC using a mixed carrier gas. Hydrogen is typically analyzed with argon carrier gas on a thermal conductivity detector. Argon however, will result in a decreased sensitivity for the other permanent gases. Helium carrier gas is, in most cases, also not a suitable alternative. Mixtures of helium and hydroge...

Self-compression of attosecond high-order harmonic pulses in the harmonic generation medium itself has been demonstrated. The attosecond pulses were generated in an argon-filled gas cell and compressed by exploiting the dispersion characteristics of argon. Since the harmonic generation medium itself was used as the compression medium, continuous chirp control was easily achieved by adjusting th...

The recent fragmentation data for central collisions of Gold on Gold are even qualitatively different from those for central collisions of Argon on Scandium. The latter can be fitted with a lattice gas model calculation. Effort is made to understand why the model fails for Gold on Gold. The calculation suggests that the large Coulomb interaction which is operative for the larger system is respo...

A new diagnostic technique for determining neutral gas and metal vapor densities over a wide pressure range with high time resolution is described. A compact, current-stabilized hollow cathode/anode discharge is use to ionize the gas and/or trace impurity to be analyzed. We report proof-of-principle operation of the diagnostic in a well characterized argon discharge in the pressure range 6.7–26...

* Work supported by U. S. Department of Energy, contract number DE-AC03-76F00515 Using laboratory scale and full size PEP-II vacuum chambers, chemical cleaning, glow discharge and thermal process effects were evaluated using surface analysis by xray photoelectron spectroscopy (XPS). These processes were optimized to reduce surface carbon and thereby minimize photodesorption gas loads. The relat...