Preparation of Large Area Anodic Alumina Membranes and their Application to Thin Film Fuel Cell

The design of an electrochemical reactor for the preparation of self-supported comparatively thin (up to 10 μm) and large area (up to 50 cm2) anodic alumina membranes is described allowing growth of porous alumina at high applied potential (up to 150 V) without burning. Residual Al and barrier oxide beneath the porous film are dissolved through a vessel equipped with a gaskets system, which allows to expose to the dissolving solution an Al area lower than the anodised surface on the front leading to self-supported alumina membranes. According to scanning electron microscopy inspection and Hg-porosity measurements, the anodizing cell and conditions lead to the production of 25 and 50 cm2 Al2O3 porous layers with structural and morphological features very similar to those shown by commercial membranes (pore diameters 200 nm and pore densities 1012 pores/m2). The application of such large area membranes as support of inorganic proton conductors in thin film fuel cell proves their performance scalability.

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Fabrication of Vertical Cu2ZnSnS4 Nanowire Arrays by Two-Step Electroplating Method into Anodic Aluminum Oxide Template

Vertical Cu2ZnSnS4 (CZTS) nanowire arrays have been synthesized via two-step electroplating method into anodized aluminum oxide template. For deposition of CZTS nanowires, anodized aluminum oxide (AAO) was used as the growth mask for the growth of the nanowires. AAO templates with hole sizes of 70 nm in diameter were used in the experiments. After electroplating of CuZu/CuSn, vertical CuZu/CuSn nanowires were obtained on Mo-coated Si substrates and the typical size of nanowire and AAO of the same size.
And the elemental compositions of unannealed CuZu/CuSn nanowires about 2:1:1. Sulfurization was performed at 600 0C for 10 min in CS2 +Ar atmosphere. X-ray diffraction patterns indicate that the annealed CZTS have a kesterite structure including secondary metal and metal sulfide phases. It is found that the conditions of sulfurization treatment affect the quality of CZTS absorber layer.

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Anodic aluminum oxide doped with vanadyl citrate chelate complex anions was formed by a two-step self-organized anodization in 2 wt. % sulfuric acid containing 0.04 M V2O5 and 0.08 M citric acid at voltage range 13-23 V, and at 0 and 15 oC. The combination of two temperatures and at least four voltages (depending on the applied temperature) was applied as the operating conditions of anodization. It was found that formed nanoporous alumina was doped with vanadium (up to 0.08 at. %). The analysis of the photoluminescence of the grown oxide exhibits separate bands for the incorporated vanadyl citrate chelate anions (emission maxima at λ = 270 nm) and F – centers (emission maxima at λ = 455 nm). Moreover, due to the complex electronic structure of the incorporated anions, relatively long fluorescence decays were achieved (up to 44.6 ns). Despite incorporation of relatively large anions, pore diameter and interpore
distance were still linear functions of the voltage. Conducted research allowed to understand the fundamental aspects of the anions incorporation in the anodic alumina and allowed to form a new type of luminescent material.


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Synthesis of BaTiO3 Nanowires via Anodic Aluminum Oxide Template Method Assisted by Vacuum-and-Drop Loading

In recent years, miniaturization of sensors, actuators, capacitors and micro-electro-mechanical systems makes rapid progress. In order to realize the further miniaturization, nanostructured piezoelectric ceramics have been intensively studied. By controlling their nanostructures, one can make them to exhibit phase transition behavior and dielectric constants different from those of the bulk, partially due to the particle size effect [1-4]. To date, besides equiaxed nanoparticles and nanoceramics, one-dimensional (1-D) ferroelectric and piezoelectric nanomaterials are of great concern.


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Cholesterol Homeostasis Imbalance and Brain Functioning: Neurological Disorders and Behavioral Consequences

Cholesterol is an amphipathic sterol compound that exerts both structural and physiological tasks in the plasma membrane of all eukaryoticcells. The planar and rigid structure of this molecule regulates the fluidity of the phospholipid bilayer and its permeability to solutes and ions. The structural role of cholesterol is particularly relevant in the central nervous system, where it represents one of the major components of myelin sheaths, and an important constituent of the synaptic vesicle membranes. The synthesis and trafficking of cholesterol is highly specialized in the brain, and displays several differences if compared to its metabolism in other tissues. In humans, disruption to cholesterol homeostasis can lead to a wide spectrum of pathological conditions. The relevance of this compound in the pathogenesis of atherosclerosis and other cardiovascular diseases is nowadays well established, whilecorrelations existing betweencholesterol and brain disorders are still poorly characterized.



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Pulmonic Valve Endocarditis Complicating Streptococcus pneumoniae Community- Acquired Pneumonia

Infective endocarditis is most often seen affecting the left side of the heart, with the pulmonary valve being the least frequently involvedvalve. The most common organisms responsible for infective endocarditis are Staphylococcus aureus and Streptococcus viridans. Here we report a rare case of pulmonary valve endocarditis due to Streptococcus pneumoniae, a rare pathogen for this setting. The clinical features, presentation, and review of the literature are discussed.


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Therapeutic Hypothermia Still Effective in Prevention of Anoxic Encephalopathy following Extended Period of Pulselessness during Cardiac Arrest

There are approximately 300,000 out-of-hospital cardiac arrests per year with less than 10% of those surviving. More than half ofsurvivors suffer permanent neurologic deficits. Therapeutic hypothermia has proven effective at thwarting neurologic damage occurringin the 16-hour window following return of spontaneous circulation (ROSC). Despite recommendations by the American HeartAssociation (AHA), many cardiologists have been slow to implement therapeutic hypothermia. While many trials have discussed therelevance of initial rhythm and delay of cooling, there has been limited discussion of the efficacy of therapeutic hypothermia in the presence of extended pulselessness.


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