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Interface Layer (interface + layer)
Selected AbstractsVertically Aligned Nanocomposite Thin Films as a Cathode/Electrolyte Interface Layer for Thin-Film Solid Oxide Fuel CellsADVANCED FUNCTIONAL MATERIALS, Issue 24 2009Jongsik Yoon Abstract A thin layer of a vertically aligned nanocomposite (VAN) structure is deposited between the electrolyte, Ce0.9Gd0.1O1.95 (CGO), and the thin-film cathode layer, La0.5Sr0.5CoO3 (LSCO), of a thin-film solid-oxide fuel cell (TFSOFC). The self-assembled VAN nanostructure contains highly ordered alternating vertical columns of CGO and LSCO formed through a one-step thin-film deposition process that uses pulsed laser deposition. The VAN structure significantly improves the overall performance of the TFSOFC by increasing the interfacial area between the electrolyte and cathode. Low cathode polarization resistances of 9,×,10,4 and 2.39,, were measured for the cells with the VAN interlayer at 600 and 400,°C, respectively. Furthermore, anode-supported single cells with LSCO/CGO VAN interlayer demonstrate maximum power densities of 329, 546, 718, and 812,mW cm,2 at 550, 600, 650, and 700,°C, respectively, with an open-circuit voltage (OCV) of 1.13,V at 550,°C. The cells with the interlayer triple the overall power output at 650,°C compared to that achieved with the cells without an interlayer. The binary VAN interlayer could also act as a transition layer that improves adhesion and relieves both thermal stress and lattice strain between the cathode and the electrolyte. [source] A Computational Approach on the Osseointegration of Bone Implants Based on a Bio-Active Interface TheoryGAMM - MITTEILUNGEN, Issue 2 2009André Lutz Abstract In this presentation an integrated approach on the simulation of osseointegration in the boneimplant interface is outlined. Besides the consistent combination of computational bone remodelling simulation and established medical imaging techniques, a new model refinement in terms of a bioactive interface theory is introduced, which enables the simulation of bone ingrowth in rough coated uncemented implants. Under consideration of seven physiological loads of daily motion the bone-implant relative micromotion in a soft tissue region around the endoprosthesis is investigated. As the micromotions are an important factor for osseointegration, because excessive micromotion leads to apposition of fibrous tissue, they are considered for the simulation of osseointegration. Results for different parameter constellations, regarding thickness and stiffness of bone-implant interface layer, are compared and the ingrowth for different configurations is predicted. With these results conclusions can be made about the stability of prosthesis in the host bone, which is an important factor for the clinical success of the treatment (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Anatomy and lifestyles of Early Cambrian priapulid worms exemplified by Corynetis and Anningvermis from the Maotianshan Shale (SW China)LETHAIA, Issue 1 2004DI-YING HUANG Accurate information on the anatomy and ecology of worms from the Cambrian Lagerstätten of SW China is sparse. The present study of two priapulid worms Anningvermis n. gen. and Corynetis Luo & Hu, 1999 from the Lower Cambrian Maotianshan Shale biota brings new information concerning the anatomical complexity, functional morphology and lifestyles of the Early Cambrian priapulids. Comparisons are made with Recent priapulids from Sweden (live observations, SEM). The cuspidate pharyngeal teeth of Anningvermis (circumoral pentagons) and the most peculiar radiating oral crown of Corynetis added to the very elongate pharynx of these two forms are interpreted as two different types of grasping apparatus possibly involved in the capture of small prey. Corynetis and Anningvermis are two representative examples of the Early Cambrian endobenthic communities largely dominated by priapulid worms (more than ten species in the Maotianshan Shale biota) and to a much lesser extent by brachiopods. Corynetis and Anningvermis were probably active mud-burrowers and predators of small meiobenthic animals. Likewise predator priapulid worms exploited the interface layer between the seawater and bottom sediment, where meiobenthic organisms were abundant and functioned as prey. This implies that complex prey-predator relationship between communities already existed in the Early Cambrian. This study also shows that the circumoral pentagonal teeth and caudal appendage were present in the early stages of the evolutionary history of the group and were important features of the priapulid body plan already in the Early Cambrian. Two new families, one new genus and new species are introduced and described in the appendix. [source] Evaluation of a Non-Woven Fabric Coated with a Chitosan Bi-Layer Composite for Wound DressingMACROMOLECULAR BIOSCIENCE, Issue 5 2008Bai-Shuan Liu Abstract This study presents a novel design of an easily stripped bi-layer composite that consists of an upper layer of a soybean protein non-woven fabric coated with a lower layer, a genipin-crosslinked chitosan film, as a wound dressing material. This study examines the in vitro properties of the genipin-crosslinked chitosan film and the bi-layer composite. Furthermore, in vivo experiments are conducted to study wounds treated with the composite in a rat model. Experimental results show that the degree of crosslinking and the in vitro degradation rate of the genipin-crosslinked chitosan films can be controlled by varying the genipin contents. In addition, the genipin contents should exceed 0.025 wt.-% of the chitosan-based material if complete crosslinking reactions between genipin and chitosan molecules are required. Water contact angle analysis shows that the genipin-crosslinked chitosan film is not highly hydrophilic; therefore, the genipin-crosslinked chitosan layer is not entangled with the soybean protein non-woven fabric, which forms an easily stripped interface layer between them. Furthermore, this new wound dressing material provides adequate moisture, thereby minimizing the risk of wound dehydration, and exhibits good mechanical properties. The in vivo histological assessment results reveal that epithelialization and reconstruction of the wound are achieved by covering the wound with the composite, and the composite is easily stripped from the wound surface without damaging newly regenerated tissue. [source] Assembly, structure, and performance of an ultra-thin film organic field-effect transistor (OFET) based on substituted oligothiophenesPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 3 2008K. Haubner Abstract We report on the improved assembly and characterization of a small molecule organic field-effect transistor (OFET). Novel ,,,-dicyano substituted ,,,,-dibutylquaterthiophene molecules (DCNDBQT) were synthesized and characterized by UV,Vis spectroscopy, differential scanning calorimetry, thermal gravimetric analysis and cyclic voltammetry. The ultra-thin organic film formation on TiO2 templates was effectively promoted through the specifically designed bifunctional self assembly molecules (SAM) 5-cyano-2-(butyl-4-phosphonic acid)-3-butylthiophene (CNBTPA). Excellent structural properties were found for up to 9 DCNDBQT molecule thick films prepared through UHV vacuum sublimation as investigated with UHV non-contact atomic force microscopy (nc-AFM) and X-ray diffraction. Both X-ray and nc-AFM data indicate that the DCNDBQT molecules form a well-ordered terraced structure exhibiting step heights of 1.5 nm to 2.0 nm layers. Hence, the DCNDBQTmolecules are linked to the functional SAM interface layer by H-bond interactions (see structure model) standing quasi perpendicular to the TiO2 template, and thus providing optimal orbital overlap neigh-bouring thiophene rings. The vacuum sublimated DCNDBQT molecules form a closed packed and dense molecular layer that was used to construct and operate a nanoscopic OFET-structure. The resulting field mobilities of 10,5 cm2 V,1 s,1 reflect a high current density in our ultrathin but highly ordered structure. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Scanning capacitance microscopy as a tool for the assessment of unintentional doping in GaNPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue S2 2009Rachel A. Oliver Abstract Scanning capacitance microscopy (SCM) is a technique based on atomic force microscopy which provides information about the concentration and distribution of charge carriers in a semiconducting sample. As an imaging technique it provides an advantage over more conventional approaches such as secondary ion mass spectrometry and depth-profiling Hall voltage measurement since it provides a two-dimensional dataset rather than a one dimensional line profile. Here, we demonstrate the utility of SCM for GaN-based materials by assessing the unintentionally doped layer at the GaN/sapphire interface in a series of samples in which the growth conditions initially favoured the formation of three-dimensional islands, which later coalesced to form a two-dimensional film. Using SCM we observe that the width of the resulting conductive layer at the GaN/sapphire interface depends on the time taken to achieve coalescence but that the carrier density does not. We also assess and attempt to explain the roughness of the top surface of the conductive interface layer, which can only be addressed using an imaging technique. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Fiber-forming blend polypropylene-polyvinyl alcoholPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 8 2001Anton Marcin Abstract The preparation of a fiber-forming blend consisting of polypropylene and polyvinyl alcohol mixed with glycerol and with polypropylene grafted with maleic anhydride were studied. The physical and mechanical properties of blend fibers were also studied. The rheological measurements for semiquantitative evaluation of technological compatibility of the components and for processing the polymeric material in extruding and spinning process were carried out. The experimental results revealed the technological compatibility of the polypropylene-polyvinyl alcohol blend in the presence of glycerol and polypropylene grafted with maleic anhydride. The colloidal structure of interface layer is assumed to be in a three- or four-component system. The mixture of polyvinyl alcohol with glycerol allows for the preparation of well spun fiber-forming polypropylene blends. Polypropylene-polyvinyl alcohol blend fibers consisting of up to 20% polyvinyl alcohol with sufficient mechanical properties, higher porosity and significantly higher sorption of water than polypropylene fibers alone were prepared. Copyright © 2001 John Wiley & Sons, Ltd. [source] Small scale mixing processes at the top of a marine stratocumulus,a case studyTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 622 2007Krzysztof E. Haman Abstract A layer of intensive mixing (entrainment interface layer, [EIL]) at the top of marine stratocumulus under a strong inversion has been investigated with 10 cm resolution using an ultrafast thermometer (UFT-F; temperature), a particle volume monitor PVM,100A (liquid water content), and a fast forward scattering spectrometer probe (FFSSP; droplet spectra). Measurements were collected on board the NCAR C-130 aircraft during research flight RF05 of DYCOMS-II field study. The EIL consists of mutual filaments of cloudy and clear air at different stages of stirring, mixing, and homogenization. Borders between these filaments are often very sharp, with the 10 cm resolution of the instruments being insufficient to characterize them properly in many cases. Certain classifications of these filaments and hypotheses about the mechanisms of their formation have been proposed. The common occurrence of filaments of sizes smaller than the resolution of instruments has been indirectly confirmed. This is in agreement with the observed cloud droplet spectra showing variations of droplet number concentration without significant change of the mean droplet diameter and spectrum width. Copyright © 2007 Royal Meteorological Society [source] Roll-Bonded Titanium/Stainless-Steel Couples, Part 1: Diffusion and Interface-Layer InvestigationsADVANCED ENGINEERING MATERIALS, Issue 1-2 2009S. Dziallach A survey of the diffusion of the alloying elements Fe, Ni and Cr in a roll-bonded titanium/stainless-steel couple after an application-orientated heat treatment is presented. Diffusion profiles of the investigated elements by means of EPMA, and the diffusion coefficients and activation energies for application-oriented short annealing times up to 12,min in a temperature range of 750 to 950,°C are determined. The transformation of the hcp , -titanium into bcc , -titanium has a significant influence on the diffusion of the elements. The forming interface layers are characterised by LOM and SEM pictures. [source] | ||||||||||||||||