The addition of chromium and molybdenum to nickel creates alloys with exceptional corrosion resistance in a diverse range of environments. This study examines the complementary roles of Cr and Mo in Ni alloy passivation. Four nickel alloys with varying amounts of chromium and molybdenum were studied in 1 molar salt solutions over a broad pH range. The passive corrosion and breakdown behavior of the alloys suggests that chromium is the primary element influencing general corrosion resistance. The breakdown potential was nearly independent of molybdenum content, while the repassivation potential is strongly dependant on the molybdenum content. This indicates that chromium plays a strong role in maintaining the passivity of the alloy, while molybdenum acts to stabilize the passive film after a localized breakdown event.

We describe an exploratory optical design for the Narrow Field InfraRed Adaptive Optics (AO) System (NFIRAOS) Petite, a proposed adaptive optics system for the Thirty Meter Telescope Project. NFIRAOS will feed infrared spectrograph and wide-field imaging instruments with a diffraction limited beam. The adaptive optics system will require multi-guidestar tomographic wavefront sensing and multi-conjugate AO correction. The NFIRAOS Petite design specifications include two small 60 mm diameter deformable mirrors (DM's) used in a woofer/tweeter or multiconjugate arrangement. At least one DM would be a micro-electromechanical system (MEMS) DM. The AO system would correct a 10 to 30 arcsec diameter science field as well as laser guide stars (LGS's) located within a 60 arcsec diameter field and low-order or tip/tilt natural guide stars (NGS's) within a 60 arcsec diameter field. The WFS's are located downstream of the DM's so that they can be operated in true closed-loop, which is not necessarily a given in extremely large telescope adaptive optics design. The WFS's include adjustable corrector elements which correct the static aberrations of the AO relay due to field position and LGS distance height.

Over the last 10 years a mix of innovative and conventional characterization techniques has been used to assess the contamination of vadose zone sediments beneath the pilot-scale test facility known as TNX at the Savannah River Site (SRS) in South Carolina. Shallow soils and groundwater beneath the TNX facility are contaminated with chlorinated volatile organic compounds (CVOCs), trichloroethylene (TCE), carbon tetrachloride (CCl{sub 4}), perchloroethylene (PCE), and chloroform (CHCl{sub 3}). An interim pump and treat remediation system was placed in operation in 1996 to provide hydraulic containment of groundwater containing greater than 500 ug/L dissolved TCE. In 1994, a vadose zone study was initiated to determine the degree and extent of CVOC contamination above the contaminated groundwater. Headspace sampling and analysis, acoustic infrared spectroscopy, cone penetrometry, and vadose zone pumping tests were used to determine contaminant concentrations and physical properties related to soil vapor extraction. In 2001, soil vapor extraction (SVE), a presumptive remedy for CVOCs in soils similar to those present beneath TNX, was selected to treat the CVOC contamination. Cone Penetrometer Testing (CPT) with soil vapor sampling provided a detailed understanding of the subsurface geology and CVOC distribution which was essential for proper well design and placement. Twelve SVE …

We discuss quark antiquark energies and the screening mass in hot QCD using the non-perturbative lattice approach. For this purpose we analyze properties of quark antiquark energies and entropies at infinitely large separation of the quark antiquark pair at low and high temperatures. In the limit of high temperatures these energies and entropies can be related perturbatively to the temperature dependence of the Debye mass and the coupling. On the one hand our analysis thus suggests that the quark antiquark energies at (infinite) large distances are rather related to the Debye screening mass and the coupling than to the temperature dependence of heavy-light meson masses. On the other hand we find no or only little differences in all mass scales introduced by us when changing from quenched to 2-flavor QCD at temperatures which are only moderately above the phase transition.

The authors present evidence for the flavor-changing neutral current decay B {yields} K*{ell}{sup +}{ell}{sup -} and a measurement of the B {yields} K{ell}{sup +}{ell}{sup -} branching fraction, where {ell}{sup +}{ell}{sup -} is either an e{sup +}e{sup -} or {mu}{sup +}{mu}{sup -} pair. The data sample analyzed comprises 88.5 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring. Averaging over K{sup (*)} isospin and lepton flavor, we obtain {Beta}(B {yields} K*{ell}{sup +}{ell}{sup -}) = (1.40{sub -0.49}{sup +0.57} {+-} 0.21) x 10{sup -6} and {Beta}(B {yields} K{ell}{sup +}{ell}{sup -}) = (0.68{sub -0.15}{sup +0.17} {+-} 0.04) x 10{sup -6}, where the uncertainties are statistical and systematic. The significance for the B {yields} K*{ell}{sup +}{ell}{sup -} signal is 3.0{sigma} and for B {yields} K{ell}{sup +}{ell}{sup -} the signal significance is over 7{sigma}.

The creation of ultra-high current, ultra-short pulse beams Q=3 nC, {sigma}{sub z} = 20{micro}m at the SLAC FFTB has opened the way for very high gradient plasma wakefield acceleration experiments. We study here the use of these beams in a proposed Cherenkov wakefield experiment, where one may excite electromagnetic wakes in a simple dielectric tube with inner diameter of few 100 microns that exceed the GV/m level. We discuss the scaling of the fields with design geometric design parameters, and choice of dielectric. We also examine measurable aspects of the experiment, such as the total coherent Cerenkov radiation energy one may collect, and the expected aspects of dielectric breakdown at high fields.

We study the density of states method to explore the phase diagram of the chiral transition on the temperature and quark chemical potential plane. Four quark flavors are used in the analysis. Though the method is quite expensive small lattices show an indication for a triple-point connecting three different phases on the phase diagram.