Plasma-Enhanced ALD of TiO2 Thin Films on SUS 304 Stainless Steel for Photocatalytic Application

Plasma-enhanced atomic layer deposition (PE-ALD) of TiO2 thin films using Ti(NMe2)(4) [tetrakis(dimethylamido) Ti] and O-2 plasma were prepared on stainless steel to show the self-cleaning effect. The TiO2 thin films deposited on stainless steel have high growth rate, large surface roughness, and low impurities. The film deposited below 200 degrees C was amorphous, while the films deposited at 300 and 400 degrees C showed anatase and rutile phases, respectively. The contact angle measurements on crystalline PE-ALD TiO2 thin films exhibited superhydrophilicity after UV irradiation. The TiO2 thin film with anatase phase deposited at 300 degrees C showed the highest photocatalytic efficiency, which is higher than on Activ glass or thermal ALD TiO2 films. We suggest that anatase structure and large surface area of TiO2 thin film on stainless steel are the main factors for the high photocatalytic efficiency. (C) 2009 The Electrochemical Society. [DOI: 10.1149/1.3095515] All rights reserved.X117sciescopu

Effects of Fluorine Plasma Treatment on the Electronic Structure of Plasma-Enhanced Atomic Layer Deposition HfO2

We investigated the effects of fluorine treatments on the electrical properties and electronic structures of plasma-enhanced atomic layer deposition HfO2 gate oxides, depending on the treatment process. Pre- and postoxide-deposition fluorine treatments were carried out using CF4 plasma. Improved dielectric properties were achieved by predeposition treatment, while degradation of electrical properties was observed for postdeposition treatment. Based on the electronic structure analysis using X-ray photoemission spectroscopy and near-edge X-ray absorption fine structures, we found that the enhanced dielectric properties of the pretreated HfO2 are induced by the defect passivation and conduction-band offset increase. (C) 2009 The Electrochemical Society. [DOI: 10.1149/1.3089976] All rights reserved.open111010sciescopu

Obstructive Jaundice in Polycystic Liver Disease Related to Coexisting Cholangiocarcinoma

Although jaundice rarely complicates polycystic liver disease (PLD), secondary benign or malignant causes cannot be excluded. In a 72-year-old female who presented with increased abdominal girth, dyspnea, weight loss and jaundice, ultrasound and computed tomography confirmed the diagnosis of PLD by demonstrating large liver cysts causing extrahepatic bile duct compression. Percutaneous cyst aspiration failed to relief jaundice due to distal bile duct cholangiocarcinoma, suspected by magnetic resonance cholangiopancreatography (MRCP) and confirmed by endoscopic retrograde cholangiopancreatography (ERCP). Coexistence of PLD with distal common bile duct cholangiocarcinoma has not been reported so far

Face-selective electrostatic control of hydrothermal zinc oxide nanowire synthesis

Rational control over the morphology and the functional properties of inorganic nanostructures has been a long-standing goal in the development of bottom-up device fabrication processes. We report that the geometry of hydrothermally grown zinc oxide nanowires can be tuned from platelets to needles, covering more than three orders of magnitude in aspect ratio (~0.1–100). We introduce a classical thermodynamics-based model to explain the underlying growth inhibition mechanism by means of the competitive and face-selective electrostatic adsorption of non-zinc complex ions at alkaline conditions. The performance of these nanowires rivals that of vapour-phase-grown nanostructures and their low-temperature synthesis (<60 °C) is favourable to the integration and in situ fabrication of complex and polymer-supported devices. We illustrate this capability by fabricating an all-inorganic light-emitting diode in a polymeric microfluidic manifold. Our findings indicate that electrostatic interactions in aqueous crystal growth may be systematically manipulated to synthesize nanostructures and devices with enhanced structural control.National Science Foundation (U.S.) (MIT Center for Bits and Atoms (NSF CCR0122419))Massachusetts Institute of Technology. Media LaboratoryKorea Foundation for Advanced StudiesSamsung Electronics Co. (research internship)Harvard University. Society of FellowsWallace H. Coulter Foundation (Early Career Award)Brain & Behavior Research Foundation (Young Investigator Award)National Science Foundation (U.S.)National Institutes of Health (U.S.) (Director’s New Innovator Award

Control of electronic conduction at an oxide heterointerface using surface polar adsorbates

The transfer of electrons between a solid surface and adsorbed atomic or molecular species is fundamental in natural and synthetic processes, being at the heart of most catalytic reactions and many sensors. In special cases, metallic conduction can be induced at the surface of, for example, Si-terminated SiC1, or mixed-terminated ZnO2, in the presence of a hydrogen adlayer. Generally, only the surface atoms are significantly affected by adsorbates. However, remotely changing electronic states far from the adsorbed layer is possible if these states are electrostatically coupled to the surface. Here we show that the surface adsorption of common solvents such as acetone, ethanol, and water can induce a large change (factor of three) in the conductivity at the buried interface between SrTiO3 substrates and LaAlO3 thin films3-8. This phenomenon is observed only for polar solvents. Our result provides experimental evidence that adsorbates at the LaAlO3 surface induce accumulation of electrons at the LaAlO3/SrTiO3 interface, suggesting a general polarization-facilitated electronic transfer mechanism, which can be used for sensor applications.Comment: 14 pages, 4 figure

Search for Charged Higgs Bosons in e+e- Collisions at \sqrt{s} = 189 GeV

A search for pair-produced charged Higgs bosons is performed with the L3 detector at LEP using data collected at a centre-of-mass energy of 188.6 GeV, corresponding to an integrated luminosity of 176.4 pb^-1. Higgs decays into a charm and a strange quark or into a tau lepton and its associated neutrino are considered. The observed events are consistent with the expectations from Standard Model background processes. A lower limit of 65.5 GeV on the charged Higgs mass is derived at 95 % confidence level, independent of the decay branching ratio Br(H^{+/-} -> tau nu)

Long term follow up after surgery in congenitally corrected transposition of the great arteries with a right ventricle in the systemic circulation

Aim of the study: To investigate the long-term outcome of surgical treatment for congenitally corrected transposition of the great arteries (CCTGA), in patients with biventricular repair with the right ventricle as systemic ventricle.Methods: A total of 32 patients with CCTGA were operated between January 1972 and October 2008. These operations comprised 18 patients with a repair with a normal left ventricular outflow tract, 11 patients with a Rastelli repair of the left ventricle to the pulmonary artery and 3 patients with a cardiac transplantation.Results: Excluding the cardiac transplantation patients, mean age at operation was 16 years (sd 15 years, range 1 week - 49 years). Median follow-up was 12 years (sd 10 years, range 7 days - 32 years). Survival obtained from Kaplan-Meier analysis at 20 years after surgery was 63% (CI 53-73%). For the non-Rastelli group these data at 20 years were

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO