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Cu-based nanoparticles supported on three different carbon materials including: activated carbon (AC), ordered mesoporous carbon (OMC), and multiwalled carbon nanotubes (CNT) were prepared by ultrasonic assisted incipient-wetness impregnation and evaluated in oxidative carbonylation of methanol under atmosphere pressure. Samples were characterized by BET, XRD, TEM, H 2 -TPR and XPS. The pore structure of carbon supports had significantly affected the location and dispersion of Cu species and the increased surface oxygenated groups promote Cu 2+ reduced to (Cu +  + Cu 0 ). The Cu/OMC catalyst showed superior initial activity than Cu/AC and Cu/CNT catalysts because of smaller particle size of Cu species and moderate amounts of active species. The Cu/CNT catalyst was more stable than Cu/AC and Cu/OMC during the reaction process, and its deactivation is due to the oxidation of the active Cu 2 O and Cu. Unlike Cu/CNT, the deactivation of Cu/OMC and Cu/AC was caused by the oxidation of the active Cu species (Cu 2 O + Cu 0 ) and the increased particle size of Cu species. [ABSTRACT FROM AUTHOR]

The present study examines the cause of fluorine detection during the corrosion of the TiN antireflection coat (ARC) layer of AlSiCu metal lines. When a crack is generated in the tetraethyl orthosilicate (TEOS) oxide or spin-on-glass (SOG) film of an LSI device, the corrosion of the TiN ARC layer (TiO x N y -oxidation) may occur due to residual moisture inside the device. In this case, concentrated fluorine is detected around the corroded TiN ARC layer by energy-dispersive X-ray spectroscopy (EDX) analysis. Fluorine concentration was correlated with the degree of corrosion on the TiN ARC layer, suggesting the contribution of fluorine to the corrosion of this layer. When a wider distribution of fluorine concentrations was evaluated, however, the concentration of fluorine and the degree of corrosion on the TiN ARC layer did not match; instead, a higher concentration of fluorine was observed near the crack of the TEOS oxide film. The corroded TiN ARC layer of the sample was then removed, and the Al line of the underlying layer was observed. Etching was observed on the Al line surface where a high concentration of fluorine was detected. More specifically, EDX analysis detected that fluorine reacted with the Al line in the underlying layer after diffusion through the TiO x N y film, causing decreased film density due to the corrosion of the TiN ARC layer. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we extend the feature descriptor known as Shape of Gaussian (SOG) and we call the new descriptor Extended Shape of Gaussian (ESOG). SOG has a matrix Lie group structure, it use the geodesic distance to measure the difference between two features. First, we decompose geodesic distance on the Lie algebra into two orthogonal components. By adjusting the weights of components, we get a distance sequence. Then we identify that every element in the sequence corresponds to an element of the original Lie group, a matrix. All these matrices form ESOG. Thus the new descriptor utilizes a matrix set rather than one matrix to describe feature. In this view, SOG and region covariance are both special element of ESOG. So we can choose different element from it for different application. Noting that different elements in the ESOG describe a signal in a different view, we propose an adaptive method to select appropriate ESOG element for visual tracking. The element selected by this method is called Adaptive SOG (ASOG). ASOG keeps the advantages of both SOG and region covariance and has better accuracy and robustness under different conditions. Experiments show the tracking results compared with SOG. [Copyright &y& Elsevier]

Abstract: Most embedded optical waveguide biosensors require low dielectric optical material. The prerequisites for such applications include the selection of an appropriate material and effective bio-functionalization. Spin-on glass (SOG) is one of the preferred polymers that can be easily deposited. Further, the chemical properties of the polymer make it amenable for bio-functionalization. This paper reports a detailed study of a protocol for immobilization of antibodies on SOG for possible immunobiosensor applications. The effect of silanization at different pH values on the number of free and usable amine sites was quantified by fluorimetry. Contact angle measurements, ellipsometry, AFM, and fluorescence microscopy was used for assessing the surface properties at various stages of preparation, functionalization and biomolecule immobilization. [Copyright &y& Elsevier]

Abstract: Polymer spin coating, surface plasma treatment and selective UV-lithography processes have been developed to realize 2.5D photonic micro-resonators, made of disk- or ring-shaped upper rib waveguides, using common polymers such as SU8 (biphenol A ether glycidyl), PS233 (polymeric silane) and SOG (siloxane Spin on Glass). Both oxygen and argon plasma treatments, applied to PS233 and SOG before spin-coating the SU8, improve substantially the grip of multilayer devices (SU8 / PS233 or SU8 / SOG). Surface energy components derived from contact angle measurements have been used to optimize the processing conditions. In such integrated photonic devices, the both single-electromagnetic-modes called transverse electric (TE00) and transverse magnetic (TM00) have been excited in a SU8 micro-disk, with a single mode propagation strongly localized near the edge of the disk (i.e. the so called whispering gallery modes). [Copyright &y& Elsevier]

Abstract: Silicone polymer (PDMS), widely used for micro-fluidic and biosensor applications, possesses an extremely dynamic surface after it is subjected to an oxygen plasma treatment process. The surface becomes extremely hydrophilic immediately after oxygen plasma exposure by developing silanol bond (Sih promotes its adhesion to some other surfaces like, silicon, silicon dioxide, glass, etc. Such a surface, if left in ambient dry air, shows a gradual recovery of hydrophobicity. We have found an identical behavior to occur to surfaces coated with a thin continuous film of SOG (methyl silsesquioxane). The chemistry induced by oxygen plasma treatment of a spin-on-glass (SOG) coated surface provides a much higher density of surface silanol groups in comparison to precleaned glass, silicon or silicon dioxide substrates thus providing a higher bond strength with polydimethyl siloxane (PDMS). The bonding protocol developed by using the spin coated and cured SOG intermediate layer provides an universal regime of multi level wafer bonding of PDMS to a variety of substrates. The paper describes a contact angle based estimation of bond strength for SOG and PDMS surfaces exposed to various combinations of plasma parameters. We have found that the highest bond strength condition is achieved if the contact angle on the SOG surface is less than 10°. [Copyright &y& Elsevier]

Abstract: Line beam excimer laser annealing (ELA) is a well-known technique for thin Si-film crystallization and established in LTPS mass production. With introduction of sequential lateral solidification (SLS) some aspects such as crystalline quality, throughput and flexibility regarding the substrate size could be improved, but for OLED manufacturing still further process development is necessary. This paper discusses line beam ELA and SLS-techniques that might enable process engineers to make polycrystalline-silicon (poly-Si) films with a high degree of uniformity and quality as required for system on glass (SOG) and active matrix organic light emitting displays (AMOLED). Equipment requirements are discussed and compared to previous standards. SEM-images of process examples are shown in order to demonstrate the viability. [Copyright &y& Elsevier]

Alkylene groups incorporated porous silica films were prepared by using hydrolysis and condensation of BIS (Triethoxysilyl) Ethelene (BTE). BTE and H2O containing HCl as a catalyst were mixed with organic solvent, 2-Methylpentane-2,4-diol (MPD). FT-IR peaks due to MPD were not observed but Si–C2H4–Si related peaks were still observed in the film even after 450°C vacuum annealing. Electric characteristics were evaluated with an MOS structure. K value does not depend on the annealing temperature below 400°C; however, it was reduced down to 1.9 at 450°C. [Copyright &y& Elsevier]

How broadly expressed repressors regulate gene expression is incompletely understood. To gain insight, we investigated how Suppressor of Hairless—Su(H)—and Runt regulate expression of bone morphogenetic protein (BMP) antagonist short-gastrulation via the sog_Distal enhancer. A live imaging protocol was optimized to capture this enhancer's spatiotemporal output throughout the early Drosophila embryo, finding in this context that Runt regulates transcription initiation, Su(H) regulates transcription rate, and both factors control spatial expression. Furthermore, whereas Su(H) functions as a dedicated repressor, Runt temporally switches from repressor to activator. Our results demonstrate that broad repressors play temporally distinct roles and contribute to dynamic gene expression. Both Run and Su(H)'s ability to influence the spatiotemporal domains of gene expression may serve to counterbalance activators and function in this manner as important regulators of the maternal-to-zygotic transition in early embryos. • Roles for broadly expressed repressors, Su(H) and Runt, investigated by live imaging • Mutant and wild-type sog_Distal enhancer reporter outputs were quantitatively compared • Su(H) impacts transcription levels whereas Run regulates transcription initiation • Run switches roles in time from repressor to activator The study by Koromila and Stathopoulos defines roles for broadly expressed repressors Suppressor of Hairless and Runt in supporting dynamic gene expression in early Drosophila embryos. Using live in vivo imaging and quantitative analysis of reporter outputs, they demonstrate that these factors support different functions, affecting transcription initiation versus levels. [ABSTRACT FROM AUTHOR]