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Intermediate Layer (intermediate + layer)
Selected AbstractsFatigue resistance of dentin/composite interfaces with an additional intermediate elastic layerEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2005Jan De Munck According to the ,elastic bonding' concept, a thick intermediate layer of flexible resin has been suggested to absorb part of the polymerization shrinkage stress and to absorb shocks during function. In this study, the effect of an additional intermediate layer of a low-viscosity resin on the microrotary fatigue resistance (µRFR) of a hybrid composite bonded to dentin was evaluated. The hypotheses tested were that an intermediate layer of a low-viscosity resin (i) increases the µRFR to dentin, but (ii) has no effect on the static bond strength. Microtensile bond strength (µTBS) samples were loaded until failure or inserted in a microrotary fatigue testing device. Specimens were tested at 4 Hz until failure or until 105 cycles were reached. An additional intermediate elastic layer had no effect on the static µTBS, but significantly lowered the median µRFR from 28.4 MPa to 21.6 MPa. However, the application of an intermediate flexible layer had, no effect on the static µTBS. In conclusion, an additional elastic intermediate layer did decrease significantly the µRFR (rejection of hypothesis i), but did not alter the µTBS (acceptance of hypothesis ii). The decrease in µRFR most likely may be explained by the lower mechanical properties of the intermediary layer. [source] Vertical distribution and behaviour of shrimp Pandalus borealis larval stages in thermally stratified water columns: laboratory experiment and field observationsFISHERIES OCEANOGRAPHY, Issue 5 2006PATRICK OUELLET Abstract By combining field data and laboratory observations of larvae in a simulated thermal gradient, we described the ontogenetic changes in vertical distribution and behaviour of early stages of shrimp Pandalus borealis in thermally stratified water columns. Both in the laboratory and at stations in the north-western Gulf of St Lawrence, the first two larval stages appear to actively select and maintain a position in the upper layer of warmer temperatures, within the thermocline and above the cold (<1°C) intermediate layer. Stage III larvae were distributed deeper in the water column and in colder waters than the previous two stages. Stage IV and V larvae showed the highest degree of swimming activity in the laboratory and a much wider range (from surface to ,200 m) in vertical distribution in the field. The shift to deeper waters and settlement to the bottom habitat appears to happen after the fifth moult, at stage VI. We propose that the pattern of vertical distribution in the field reflects the adjustment of the different developmental stages to the distribution of preferred prey. The description of the ontogenetic change in the vertical distributions and movements of early stages of P. borealis should be valuable information for future attempts to model larval transport and dispersion, and for detecting settlement/recruitment areas using 3D ocean circulation models. The identification of the thermal habitat of the different larval stages and the timing for settlement at the bottom also provides important information for the development of temperature-dependent growth models up to the first juvenile stages. [source] Cover Picture: A Novel Method to Orient Semiconducting Polymer Films (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 7 2005Mater. Abstract A new technique for orienting thin polymer semiconductor films is reported by Österbacka and co-workers on p.,1095. The technique uses the mechanical force of a shrinking polymer transferred through a polymer multilayer structure. The orientation is obtained using three polymer layers, where the uppermost layer shrinks resulting in orientation of the semiconductor film beneath the intermediate layer. The topmost and intermediate polymer films are removed to reveal the oriented surface. The cover shows a crossed-polarizer microscopy image of an oriented regio-regular poly(3-hexylthiophene) film. We present a new technique for orienting polymer semiconductor thin films. In our technique, polymer chains are rigorously oriented without using any mechanical tools and with minimal risk of film contamination. The technique is based on the mechanical force resulting from the in-plane shrinkage exerted by a shrinker (top layer) that is used to orient the semiconductor beneath an intermediate layer; the latter acting as a force mediator. The chain orientation is demonstrated by several techniques such as crossed-polarizer microscopy, atomic force microscopy, grazing-incidence X-ray diffraction, and polarized absorption. The orientation geometry is controlled by the shrinking process and the shrinker area. The semiconductivity of the film only stems from the transistor device structures under study, and the method can therefore be generalized. [source] Analytical solution of the harmonic waves diffraction by a cylindrical lined cavity in poroelastic saturated mediumINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 5 2007Y. S. Karinski Abstract This paper presents a model for the analysis of plane waves diffraction at a cavity in an infinite homogeneous poroelastic saturated medium, lined by a lining composed of four equal segments. An elastic boundary layer is placed between the cavity lining and the infinite porous medium. The boundary layer is simulated by ,elastic boundary conditions' in which the bulk matrix stress is proportional to the relative displacement between the lining and the surrounding medium matrix boundary. In addition, fluid impermeability through the intermediate layer is assumed. For the frequencies, that differ from the pseudoresonanse frequencies, the problem was reduced to the problem of an ideal elastic medium. A closed-form analytical solution of the problem was obtained using Fourier,Bessel series, the convergence of which was proven. It was shown that the number of series terms required to obtain a desired level of accuracy can be determined in advance. The influence of the medium porosity on the medium dynamic stress concentration was studied. Copyright © 2006 John Wiley & Sons, Ltd. [source] Observation of the Structure, Moisture Distribution, and Oil Distribution in the Coating of Tempura by NMR Micro ImagingJOURNAL OF FOOD SCIENCE, Issue 6 2003A.K. Horigane ABSTRACT: The 3-layered fine structure of the coating of the Japanese oil-fried battered food, tempura, was observed by nuclear magnetic resonance micro imaging. The porosity of the intermediate layer was correlated to the moisture content of the batter. Chemical shift imaging, which gave moisture distribution and oil distribution images, revealed the changes in the coating after cooking. The oil was detected to a depth of only 1 mm in the outer layer immediately after frying, and its distribution slightly expanded in the surface layer with time after frying. Water quickly transferred from bean curd (tofu) as 1 ingredient, to the coating along the porous network wall within 25 min after frying. [source] Oxidation Behavior of Zirconium Diboride Silicon Carbide Produced by the Spark Plasma Sintering MethodJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2009Carmen M. Carney Dense samples of ZrB2,20 vol% SiC were successfully fabricated by spark plasma sintering without the use of sintering aids. Oxidation behavior of these samples was characterized by exposing them to 1400°, 1500°, and 1600°C in an ambient atmosphere for 150 min, and by measuring the weight gains of the sample and crucible, as well as the thickness of the oxide scale and the glassy outer layer. The effects of gravity on the viscous outer layer are shown to result in significant heterogeneity within a sample. The oxidation scales were characterized by scanning electron microscopy and transmission electron microscopy with energy dispersive spectroscopy analysis. The oxide scale was found to be composed of three layers: (1) a SiO2 -rich glassy outer layer, (2) an intermediate layer of a ZrO2 matrix with interpenetrating SiO2, and (3) a layer containing a ZrO2 matrix enclosing partially oxidized ZrB2 with Si,C,B,O glass inclusions. [source] Fabrication of Photonic/Microfluidic Integrated Devices Using an Epoxy PhotoresistMACROMOLECULAR MATERIALS & ENGINEERING, Issue 6 2010Thomas Kowpak Abstract Using a single layer of SU-8 photoresist to fabricate optical waveguide cores and microfluidic channels on Pyrex glass is an ideal way to achieve photonic/microfluidic integration on a single chip. To address the problem of poor bonding, a thin nanoscale intermediate polymer layer was applied to reduce the stress generated from the material processing while maintaining strong adhesion between the patterning polymer layer and Pyrex. It was found that a 186,600,nm thick intermediate layer of a specialty epoxy photoresist effectively served the purpose without deteriorating the optical performance of the involved waveguides. Quality photonic/microfluidic integrated devices with satisfied optical performance were fabricated. [source] Optimization of Ru intermediate layer in CoCr-based perpendicular magnetic recording mediaPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 8 2004Jong Wuk Park Abstract The influence of intermediate layer characteristics on the structural and magnetic properties of CoCr-based perpendicular media has been investigated. CoCrPt-SiO2 stacks were deposited on a 2.5-inch glass substrates. To improve intermediate layer properties without noticeable sacrifice of magnetic and structural properties of recording layer, the conditions of intermediate layer deposition were varied. The recording layer was deposited on the Ru intermediate layer in 20 mTorr Ar pressure to increase coercivity. As a result, coercivity is increased from 2.2 to 3.7 kOe because the interface between Ru intermediate layer and recording layer was rougher than the interface formed at low Ar pressure. Additionally, to increase perpendicular anisotropy of recording layer, the Ru sputtering temperature condition was varied, ranging from 150 °C to 300 °C. However, the perpendicular anisotropy of recording layer was decreased. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Unintentionally doped InN grown onto an atomically flat AlN intermediate layer using plasma-assisted molecular beam epitaxyPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 7 2006K. R. Wang Abstract Unintentionally doped InN has been grown onto an atomically flat AlN intermediate layer on top of the Si(111) substrate using plasma-assisted molecular beam epitaxy (PA-MBE). Though there are lots of micrometer-size indium droplets randomly distributed on the top of the surface, the highest electron mobility of this InN thin film measured at room temperature by van der Pauw method is still higher than 1000 cm2/V s with a carrier concentration of 5,8.9 × 1018 cm,3. A symmetrical X-ray rocking curve is measured and the full-width-at-half-maximum (FWHM) of this sample is 1089 arcsec. In the meantime, the threading dislocation (TD) density of this material is estimated to around 9.8 × 108 cm,2 , 7.5 × 109 cm,2 depending on the probing regions that are studied by the etching technique and field-emission scanning electron microscopy (FE-SEM). (2 × 1) in situ reflection high-energy electron diffraction (RHEED) patterns show that this sample is grown under In-rich environment with possible In-terminated surface. From the FE-SEM pictures which were taken from the samples after 10 minutes etching in hydrochloride, the surface morphology shows In-polarity-like patterns that coincide with those procured in RHEED. To select and grow a high-quality laminated AlN as intermediate layer is believed to be the major step in obtaining this high electron mobility InN thin film on Si substrate. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Structure of cubic polytype indium nitride layers on top of modified sapphire substratesPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 2 2008F. M. Morales Abstract The occurrence of cubic indium nitride thin layers grown by molecular beam epitaxy on top of c-plane sapphire substrates modified by an intermediate layer of cubic indium oxide is reported. An orientation relationship between the (0001) plane of Al2O3 and both (001) surfaces of body-centered cubic In2O3 and zinc-blende InN is demonstrated by means of electron and X-ray diffraction and by transmission electron microscopy. We propose that the demonstrated approach is able to stabilize the non equilibrium phase of InN (i. e., the cubic polytype) due to a low lattice mismatch together with a four fold surface atomic arrangement of the indium oxide-indium nitride interface. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Multilayer Diffusion Barrier Coatings on Poly(propylene) with Improved Temperature DurabilityPLASMA PROCESSES AND POLYMERS, Issue S1 2009Lutz Körner Abstract The improvement of temperature durability for autoclaving of silicon oxide (SiOx) diffusion barrier coatings on poly(propylene) (PP) by deposition of thin amorphous hydrogenated carbon-nitrogen (a-C:N:H) intermediate layers was investigated. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy revealed terminating amino and nitrile groups responsible for low compressive stress in a-C:N:H. Uniaxial tensile tests showed a higher crack onset strain (COS) for a-C:N:H of 2.7% compared to 0.7% for SiOx. Best temperature durability was achieved by a three-layer coating from a-C:N:H, an intermediate layer deposited by a mixture of N2, C2H2, hexamethyldisiloxane (HMDSO), and a SiOx layer. The oxygen transmission rate (OTR) was only increased from 6 to 22 cm3·m,2·d,1·bar,1 after exposure to 140,°C for 30 min, whereas for single SiOx barrier coatings, severe loss of barrier properties of 1,040 cm3·m,2·d,1·bar,1 was evidenced due to the formation of cracks. [source] Open questions in current models of antidepressant actionBRITISH JOURNAL OF PHARMACOLOGY, Issue 6 2010A Tanti Research on depression and antidepressant drugs is necessary, as many patients display poor response to therapy. Different symptomatic and pathophysiological features have been proposed as end points of the depressive phenotype and of the antidepressant action, including anhedonia, depressed mood, alterations in morphology and activity of some brain areas (amygdala, nucleus accumbens, hippocampus, prefrontal cortex and cingulate cortex), modifications in the connectivity between brain structures, changes in neurotransmitters (serotonin, noradrenaline, glutamate and neuropeptides), brain plasticity (neurogenesis, neurotrophins) and abnormal function of the hypothalamic-pituitary adrenal axis. However, few models have been proposed to describe how these end points could induce the depressive phenotype and are involved in the mechanism of action of antidepressants. Here we propose a connectionist-inspired network of depression and antidepressant action, in which the different aetiological factors participating in the release of a depressive episode are represented by input nodes, the different symptomatic as well as pathophysiological end points are represented by an intermediate layer, and the onset of depression or of comorbid disease is represented by the output node. The occurrence of depression and the mechanism of the antidepressant action thus depend upon the weight of the interactions between the different end points, none of them being per se crucial to the onset of a depressive phenotype or to the antidepressant action. This model is heuristic to draw future lines of research concerning new antidepressant therapies, designing new animal models of depression and for a better understanding of the depressive pathology and of its comorbid pathology such as anxiety disorders. [source] Density Investigation by X-ray Reflectivity for Thin Films Synthesized Using Atmospheric CVD,CHEMICAL VAPOR DEPOSITION, Issue 9-10 2008Shinichi Kishimoto Abstract The density of hafnia and titania films is investigated by an X-ray reflectivity (XRR) analysis using an X-ray diffractometer equipped with a relatively low power X-ray source. Several films are prepared using a CVD technique operated under atmospheric pressure. The XRR profile of the hafnia films is obtained, and fitted with the assumption of the existence of an HfSiO intermediate layer on the Si substrate with a SiO2 layer. The density of the hafnia films is lower than that of the bulk crystal. On the other hand, the XRR profile of the titania films on the glass substrate can be fitted using a seven-lamella model. The film density of titania is also lower than that of the bulk crystal. XRR analysis may become a powerful weapon to determine not only the structure model but also the crystallinity of each layer. [source] Optimization of the Composition of Interfaces in Miniature Planar Chloride ElectrodesELECTROANALYSIS, Issue 15-16 2003Renata Paciorek Abstract Different solid contact arrangements for miniature screen-printed electrodes and silicon based electrodes for chloride ions were investigated. As an inner contact the electrochemically deposited gold on screen-printed silver and platinum (silicon based electrodes) were used. As the ion-exchanger for chloride methyl-tri- n -tetradecylammonium chloride with PVC or Tecoflex as the polymer matrix was used. The influence of different intermediate layers between inner contact and the ion selective membrane was studied. The best characteristic of the electrode was obtained for electrodes containing gold contact and conductive polymer (poly-3-octylthiophene) with adhesive admixture between the inner contact and the proper ion selective membrane. [source] Fabrication and Optical Characteristics of Position-Controlled ZnO Nanotubes and ZnO/Zn0.8Mg0.2O Coaxial Nanotube Quantum Structure ArraysADVANCED FUNCTIONAL MATERIALS, Issue 10 2009Jinkyoung Yoo Abstract The position-controlled growth and structural and optical characteristics of ZnO nanotubes and their coaxial heterostructures are reported. To control both the shape and position of ZnO nanotubes, hole-patterned SiO2 growth-mask layers on Si(111) substrates with GaN/AlN intermediate layers using conventional lithography are prepared. ZnO nanotubes are grown only on the hole patterns at 600,°C by catalyst-free metal,organic vapor-phase epitaxy. Furthermore, the position-controlled nanotube growth method allows the fabrication of artificial arrays of ZnO-based coaxial nanotube single-quantum-well structures (SQWs) on Si substrates. In situ heteroepitaxial growth of ZnO and Zn0.8Mg0.2O layers along the circumference of the ZnO nanotube enable an artificial formation of quantum-well arrays in a designed fashion. The structural and optical characteristics of the ZnO nanotubes and SQW arrays are also investigated using synchrotron radiation X-ray diffractometry and photoluminescence and cathodoluminescence spectroscopy. [source] Soil inorganic carbon storage pattern in ChinaGLOBAL CHANGE BIOLOGY, Issue 10 2008NA MI Abstract Soils with pedogenic carbonate cover about 30% (3.44 × 106 km2) of China, mainly across its arid and semiarid regions in the Northwest. Based on the second national soil survey (1979,1992), total soil inorganic carbon (SIC) storage in China was estimated to be 53.3±6.3 PgC (1 Pg=1015 g) to the depth investigated to 2 m. Soil inorganic carbon storages were 4.6, 10.6, 11.1, and 20.8 Pg for the depth ranges of 0,0.1, 0.1,0.3, 0.3,0.5, and 0.5,1 m, respectively. Stocks for 0.1, 0.3, 0.5, and 1 m of depth accounted for 8.7%, 28.7%, 49.6%, and 88.9% of total SIC, respectively. In contrast with soil organic carbon (SOC) storage, which is highest under 500,800 mm yr,1 of mean precipitation, SIC storage peaks where mean precipitation is <400 mm yr,1. The amount and vertical distribution of SIC was related to climate and land cover type. Content of SIC in each incremental horizon was positively related with mean annual temperature and negatively related with mean annual precipitation, with the magnitude of SIC content across land cover types showing the following order: desert, grassland >shrubland, cropland >marsh, forest, meadow. Densities of SIC increased generally with depth in all ecosystem types with the exception of deserts and marshes where it peaked in intermediate layers (0.1,0.3 m for first and 0.3,0.5 m for latter). Being an abundant component of soil carbon stocks in China, SIC dynamics and the process involved in its accumulation or loss from soils require a better understanding. [source] Diamond Growth on a Si Substrate With Ceramic InterlayersJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 5 2007Y. S. Li Deposition of diamond films on Si substrates precoated with a series of ceramic intermediate layers was examined. The interlayers containing SiC, SiNx, SiCN, TiSiN, and TiAlSiN were prepared by a liquid injection plasma-enhanced chemical vapor deposition (PECVD) method using alkoxide solution precursors. The subsequent diamond synthesis on these coatings was carried out by microwave plasma-assisted CVD (MPCVD) using a H2,1%CH4 mixture. A higher nucleation density of diamond was obtained on these intermediate layers than on the as-polished Si wafer, along with a nonuniform surface distribution of diamond. Diamond powder scratching pretreatment of these interlayers enhanced the nucleation density and promoted the formation of fully uniform diamond films. Particularly, nanocrystalline diamond films were directly generated on TiSiN and TiAlSiN layers under an identical deposition condition that had favored the formation of microcrystalline diamond films on Si wafers and the Si(C,N) interlayers. The mechanism for this difference is attributed primarily to a higher amount of residual amorphous carbon in TiSiN and TiAlSiN layers than that inside Si(C,N) layers. [source] Epitaxial lateral overgrowth of GaN on 4 inch Si(111) by MOVPEPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2008Kai Cheng Abstract Epitaxial Lateral Overgrowth (ELOG) of GaN on 4 inch silicon(111) substrates by MOVPE was investigated in this study. ELOG was performed on a GaN template with a couple of AlGaN intermediate layers (IL) on an AlN nucleation layer. The AlGaN ILs supply compressive stress to the top GaN template and thereafter to the ELOG layer. Consequently, layer cracking is minimized. Two masks were used in this work: a 2 inch wagon wheel mask and a 4 inch mask with parallel stripes of various filling factors and periods. The filling factor is varied from 0.33 to 0.7. The periodic spacing is in the range of 6 ,m to 10 ,m. Temperature, V/III ratio, pressure and stripe orientation were optimized to achieve fastest lateral growth rate. The highest lateral to vertical ratio can be more than 4. A fully coalesced layer within the critical thickness for a crack-free layer was achieved on 4 inch silicon substrates. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Multilayer Diffusion Barrier Coatings on Poly(propylene) with Improved Temperature DurabilityPLASMA PROCESSES AND POLYMERS, Issue S1 2009Lutz Körner Abstract The improvement of temperature durability for autoclaving of silicon oxide (SiOx) diffusion barrier coatings on poly(propylene) (PP) by deposition of thin amorphous hydrogenated carbon-nitrogen (a-C:N:H) intermediate layers was investigated. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy revealed terminating amino and nitrile groups responsible for low compressive stress in a-C:N:H. Uniaxial tensile tests showed a higher crack onset strain (COS) for a-C:N:H of 2.7% compared to 0.7% for SiOx. Best temperature durability was achieved by a three-layer coating from a-C:N:H, an intermediate layer deposited by a mixture of N2, C2H2, hexamethyldisiloxane (HMDSO), and a SiOx layer. The oxygen transmission rate (OTR) was only increased from 6 to 22 cm3·m,2·d,1·bar,1 after exposure to 140,°C for 30 min, whereas for single SiOx barrier coatings, severe loss of barrier properties of 1,040 cm3·m,2·d,1·bar,1 was evidenced due to the formation of cracks. [source] Collagen Fiber and Versican Distribution Within the Lamina Propria of Fetal Vocal Folds,THE LARYNGOSCOPE, Issue 2 2008Rogerio Borghi Buhler MD Abstract Objectives: To analyze the presence and distribution of collagen fibers and versican in human vocal fold lamina propria of fetal larynges. Study Design: Cross sectional analysis of cadaveric vocal folds of human fetuses. Methods: Seven fetal larynges obtained from 28- to 36-week-old fetuses were analyzed with the Picrosirius-polarization method, immunohistochemistry, and image analysis. Results: Collagen fibers within the lamina propria exhibited a monolaminar distribution pattern and spatial arrangement in "wicker basket." Versican distribution was larger in the superficial and intermediate layers when compared to the deep layer. Conclusion: Our findings suggest that collagen and versican distribution and arrangement within the lamina propria in the developing fetus are important for vocalization at birth. [source] | |||||||||||||||||||||||||||||||