bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seismic wave propagation in laterally inhomogeneous poroelastic media via BIEM
Authors: Dineva Petia , Datcheva Maria , Manolis George , Schanz Tom 
Published: November 2010

SUMMARYThis work addresses in‐plane pressure P and vertically polarized shear SV seismic wave propagation in a finite, laterally inhomogeneous, multilayered poroelastic geological region resting on the homogeneous elastic half‐space. The particular approach followed here is based on a combination of the (i) viscoelastic approximation (isomorphism) to Biot's equations of dynamic poroelasticity and on the (ii) boundary integral equation method (BIEM) using frequency‐dependent fundamental solutions of the governing wave equations. The problem is formulated under plane strain conditions and time‐harmonic motions are assumed. Validation of the viscoelastic isomorphism and verification of the BIEM is done by solution of benchmark examples. These simulation studies reveal that the proposed methodology is able to depict a sensitivity of the seismic signals recovered to the following parameters: (i) poroelastic properties of fluid saturated layers; (ii) lateral geological inhomogeneity; (iii) surface topography and (iv) frequency content and direction of the incident wave. It is concluded that the combination of viscoelastic isomorphism with BIEM software provides an effective numerical tool for evaluating site‐effect phenomena in multilayered, fluid saturated geological regions with complex geometry. The numerical results obtained demonstrate that dynamic poroelasticity interacting with other physical peculiarities of the Earth's surface layers, such as lateral heterogeneity, material properties along the wave path, local geological profile and type of elastic wave, gives rise to complex seismic signals on the free surface at the site of interest. Copyright © 2010 John Wiley & Sons, Ltd.
Chronic chorioamnionitis displays distinct alterations of the amniotic fluid proteome
Authors: Oggé Giovanna , Romero Roberto , Lee Deug‐Chan , Gotsch Francesca , Than Nandor Gabor , Lee JoonHo , Chaiworapongsa Tinnakorn , Dong Zhong , Mittal Pooja , Hassan Sonia S , Kim Chong Jai 
Published: November 2010

AbstractAcute chorioamnionitis of infectious origin and chronic chorioamnionitis of immunological origin are two major placental lesions of spontaneous preterm birth with elevated amniotic fluid interleukin‐6 and CXCL10 concentrations, respectively. The changes in the amniotic fluid proteome associated with intra‐amniotic infection and acute chorioamnionitis are well defined, yet alterations unique to chronic chorioamnionitis remain to be elucidated. This study was conducted to determine those amniotic fluid proteins changing specifically in the presence of chronic chorioamnionitis. Amniotic fluid obtained from acute chorioamnionitis, chronic chorioamnionitis and gestational age‐matched controls were analysed by two‐dimensional (2D) difference in gel electrophoresis and MALDI–TOF analyses. The type of histological inflammation was used to define each condition in preterm labour cases (n = 125) and term not in labour cases (n = 22), and the amniotic fluid concentrations of interleukin‐6, CXCL8, CXCL10 and prostaglandin F2α were also measured by specific immunoassays. Among preterm labour cases, 31 differentially expressed proteins were identified in chronic chorioamnionitis cases as compared to both acute chorioamnionitis and control cases. Importantly, glycodelin‐A, which maintains maternal tolerance against an allogeneic fetus, was decreased in chronic chorioamnionitis, while haptoglobin was increased. We report the amniotic fluid proteome of chronic chorioamnionitis for the first time, and the findings herein strongly suggest that there is a pathophysiological association between the changes of immunomodulatory proteins in the amniotic fluid and chronic chorioamnionitis, a histological manifestation of maternal anti‐fetal allograft rejection. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Steric effects of substituents of quinones on the oxygenation of ethylbenzene catalyzed by NHPI/quinone and the catalytic oxidation of ascorbate
Authors: Yang Xiaomei , Wang Ying , Zhang Chaofeng , Fang Tao , Zhou Lipeng , Zhang Wei , Xu Jie 
Published: November 2010

AbstractThe substituents of quinones play an important role in modulating the kinetics of the electron‐ and proton‐transfer reaction. In this paper, the steric effects of substituents of quinones on their catalytic performance were studied in the oxidation of ethylbenzene and ascorbate. The substituents limited the addition of the free radicals to the CC double bonds of the quinone ring because of the steric hindrance. On the other hand, too many substituents hindered the contact between the active site (CO) of quinone and the reactant. So, the quinones with two substituents presented better catalytic performance than those with more or less substituents. These results will be helpful in designing the quinone compounds for drugs and in understanding the catalytic behavior of quinones in biochemistry. Copyright © 2010 John Wiley & Sons, Ltd.
Kinetics and mechanism of the anilinolysis of aryl 4‐nitrophenyl thionocarbonates in aqueous ethanol
Authors: Castro Enrique A. , Acevedo Rayen , Santos José G. 
Published: November 2010

AbstractThe reactions of bis(4‐nitrophenyl), 3‐chlorophenyl 4‐nitrophenyl, and 3‐methoxyphenyl 4‐nitrophenyl thionocarbonates (1, 2, and 3, respectively) with a series of anilines are subjected to a kinetic investigation in 44 wt.% ethanol–water, at 25.0 °C and an ionic strength of 0.2 M. Under aniline excess, pseudo‐first‐order rate coefficients (kobs) are found. Plots of kobs versus aniline concentration are linear, with the slopes (kN) pH independent, kN being the rate coefficient for the anilinolysis of the thionocarbonates. The Brønsted plot (log kN vs. pKa of anilinium ions) for thionocarbonate 1 is linear, with slope (β) 0.62, which is consistent with a concerted mechanism. The Brønsted plots for thionocarbonates 2 and 3 are curved, with slopes 0.1 at high pKa for both reaction series and slopes 0.84 and 0.79 at low pKa for the reactions of 2 and 3, respectively. The latter plots are in accordance to stepwise mechanisms, through a zwitterionic tetrahedral intermediate (T±) and its anionic analogue (T−), the latter being formed by deprotonation of T± by the basic form of the buffer (HPO). The Brønsted curves are explained by a change in the rate‐limiting step, from deprotonation of T± at low pKa, to its formation at high pKa. The influence of the amine nature and the non‐leaving and electrophilic groups of the substrate on the kinetics and mechanism is also discussed. Copyright © 2010 John Wiley & Sons, Ltd.
Preparation and Performances of Castable HTPB/CL‐20 Booster Explosives
Authors: Wang Jingyu , An Chongwei , Li Gang , Liang Lei , Xu Wenzheng , Wen Kun 
Published: November 2010

AbstractHTPB/CL‐20 castable booster explosives were prepared successfully by a cast‐cured process. Scanning electron microscope (SEM) and the charge density test were employed to characterize the molding effect of HTPB/CL‐20 explosives. The propagation reliability, detonation velocity, mechanical sensitivity, thermal decomposition characteristics and thermal stability of the HTPB/CL‐20 explosives were also measured and analyzed. The results show that, when CL‐20 content is less than 91 wt.‐%, the charges with better molding effect were obtained easily. The critical diameter of HTPB/CL‐20 explosives is less than 1 mm, which exhibits good propagation reliability. When the density of HTPB/CL‐20 charge with 91 wt.‐% CL‐20 is 1.73 g cm−3, its detonation velocity can reach 8273 m s−1. Moreover, this kind of explosives has low mechanical sensitivity and good thermal stability.
PKCδ activation mediates angiogenesis via NADPH oxidase activity in PC‐3 prostate cancer cells
Authors: Kim Jeewon , Koyanagi Tomoyoshi , Mochly‐Rosen Daria 
Published: November 2010

AbstractBACKGROUNDPKCδ is generally known as a pro‐apoptotic and anti‐proliferative enzyme in human prostate cancer cells.METHODSHere, we investigated the role of PKCδ on the growth of PC‐3 human prostate cancer cells in vivo and in vitro.RESULTSWe found that sustained treatment with a specific PKCδ activator (ψδ receptor for active C kinase, ψδRACK) increased growth of PC‐3 xenografts. There was increased levels of HIF‐1α, vascular endothelial growth factor and CD31‐positive cells in PC‐3 xenografts, representative of increased tumor angiogenesis. Mechanistically, PKCδ activation increased the levels of reactive oxygen species (ROS) by binding to and phosphorylating NADPH oxidase, which induced its activity. Also, PKCδ‐induced activation of NADPH oxidase increased the level of HIF‐1α.CONCLUSIONSOur results using tumors from the PC‐3 xenograft model suggest that PKCδ activation increases angiogenic activity in androgen‐independent PC‐3 prostate cancer cells by increasing NADPH oxidase activity and HIF‐1α levels and thus may partly be responsible for increased angiogenesis in advanced prostate cancer. Prostate 71: 946–954, 2011. © 2010 Wiley‐Liss, Inc.
Nano‐hydroxyapatite colloid suspension coated on chemically modified porous silicon by cathodic bias: a suitable surface for cell culture
Authors: Sánchez Alejandra , González Jerson , García‐Piñeres Alfonso , Montero Mavis L. 
Published: November 2010

AbstractThe properties of porous silicon make it an interesting material for biological applications. However, porous silicon is not an appropriate surface for cell growth. Surface modification is an alternative that could afford a bioactive material. In this work, we report a method to yield materials by modification of the porous silicon surface with hydroxyapatite of nanometric dimensions, produced using an electrochemical process and coated on macroporous silicon substrates by cathodic bias.The chemical nature of the calcium phosphate deposited on the substrates after the experimental process and the amount of cell growth on these surfaces were characterized. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mechanism of photo catalytic degradation of Brilliant Blue colorant in water suspension with TiO2 catalyst
Authors: Cortes J. A. , Pérez‐Robles J. F. , González‐Hernández J. , Vorobiev P. , Vorobiev Y. V. , García A. G. 
Published: November 2010

AbstractWater purification by photo catalytic decomposition of Brilliant Blue colorant in water suspension was studied. This work presents experimental and theoretical results in which the mechanism is discussed of decomposition of an organic colorant’s molecule. In theoretical part, a calculation of the energy levels of the molecule and its parts derived in decomposition process based on modified FEMO modeling confirm the mechanism proposed (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study of macroporous silicon electrochemical etching in 3D structured N type silicon substrates
Authors: Kouassi Sebastien , Gautier Gael , Desplobain Sebastien , Ventura Laurent 
Published: November 2010

AbstractIn this paper, the electrochemical etching of 3D n‐type substrates is investigated. These types of 3D structures are of interest to increase the active surface of some systems. Our aim is to improve a MEMS (Micro‐Electro Mechanical System) micro fuel cell power through total surface enhancement without any modification of the cell footprint. To reach this objective, we perform a gas diffusion layer using localized macro‐porous silicon. The porous area total surface is improved through trench formation (before porous silicon etching). This is supposed to allow a better power to surface ratio for manufactured fuel cell. The Figure on the right hand side introduces the aimed MEMS based micro fuel cell. The geometrical parameters of the designed structures and the manufacturing process influence are presented. To perform 3D structures, two types of anisotropic etching techniques have been used, alkaline etching of silicon and deep reactive ion etching (DRIE). Additional steps such as a doping layer have been used to improve the results obtained with the initial micro‐fabrication process. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gradient TiO2 nanotube arrays
Authors: Cheng Jian‐Wen , Tsang Chun Kwan , Liang Fengxia , Cheng Hua , Li Yang Yang 
Published: November 2010

AbstractGradient TiO2 nanotube arrays were fabricated by anodization using an asymmetric electrode configuration. The nanotube arrays thus obtained display a gradually changing distribution of tube diameters and length across the sample plane. The application of the fabricated gradient TiO2 nanotube arrays as optical sensors is also demonstrated. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Efficient nanostructure modified interfaces for array‐based sensing based on the novel application of hard/soft acid/base interactions
Authors: Gole James L. , Ozdemir Serdar 
Published: November 2010

AbstractWith a focus to develop array‐based sensor systems, select micro/nanoporous porous silicon (PS) interfaces have been formed and treated with a variety of nanostructured oxides to create an array of sensor responses for a variety of gases. A general model for the highly active and varied sensitivity of these treated interfaces is presented. This model, which takes advantage of the playoff between chemical bonding and physical adsorption to the deposited nanostructured oxides, suggests a means to selectively enhance the response to basic analyte gases by enhancing the reversible resistance increase characteristic of the response of p‐type silicon. The approach, counter to that used to promote strong interaction and chemical bond formation via hard and soft acid and base interactions (HSAB), promotes the enhancement of physisorption by applying an inverse concept. The focus, in applying the IHSAB model to the interaction of gaseous bases with the acidic nanostructure treated or untreated PS surface, is the minimization of chemical bonding and the maximization of electron transfer to the PS‐based interface, thus increasing the resistance response. The model shows potential to create array‐based devices. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Matrix metalloproteinase sensing via porous silicon microcavity devices functionalized with human antibodies
Authors: Martin Marta , Taleb Bendiab Chakib , Massif Laurent , Palestino Gabriela , Agarwal Vivechana , Cuisinier Frédéric , Gergely Csilla 
Published: November 2010

AbstractPorous silicon microcavity (PSiMc) structures were used as support material for specific sensing of matrix metalloproteinases (MMPs). For lower concentrations of MMP‐8, the structures were tested with two types of functionalization methods. Silanization of the oxidized porous silicon structures, followed by glutaraldehyde chemistry was found to give very inconsistent results. The use of biotinilated bovin serum albumin linked to the naked PSiMc was found to be an alternative method to attach the anti MMP‐8 human antibody, previously modified with streptavidin, which was further used to sense MMP‐8 (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An analytical drain current model for undoped GSDG MOSFETs including interfacial hot‐carrier effects
Authors: Djeffal Fayçal , Bentrcia Toufik , Bendib Toufik 
Published: November 2010

AbstractIn the present work, a comprehensive drain current model including the interfacial hot‐carrier degradation effects for undoped symmetric gate stack double gate (GSDG) MOSFET and the expressions of transconductance and drain conductance have been obtained. Exploiting this new device model, we have found that the incorporation of a high‐k layer between oxide region and gate metal leads to drain current enhancement, improved output conductance, increased transconductance parameter and enhanced interfacial hot‐carrier immunity. The proposed model has been validated by comparing the analytical I‐V characteristics with 2‐D numerical results. The obtained results may provide a theoretical basis and physical insights for multigate MOSFET‐based circuits design including the hot‐carrier degradation effects. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The formation of near surface SiGe layers with combined high‐dose ion implantation and flash‐lamp annealing
Authors: Voelskow Matthias , Stoimenos Ioannis , Rebohle Lars , Skorupa Wolfgang 
Published: November 2010

AbstractThe formation of near surface SiGe layers by means of combined high dose Ge ion implantation and flash lamp annealing will be addressed. Furthermore, we show that the formation of an undesirable facetted liquid/solid interface, which is well known for pulse melting in the millisecond time regime, is less pronounced due to the decreasing melting temperature of Si with increasing Ge concentration at the SiGe/Si interface. A dislocation network, which is observed by using transmission electron microscopy, is expected to play an important role to form these thin SiGe layers. We will demonstrate the depth profiles of Ge by Rutherford backscattering spectrometry and discuss the concerned mechanism. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Defects formed by pulsed laser annealing: electrical properties and depth profiles in n‐type silicon measured by deep level transient spectroscopy
Authors: Schindele David , Pichler Peter , Lorenz Jürgen , Oesterlin Peter , Ryssel Heiner 
Published: November 2010

AbstractThe ongoing downscaling of microelectronic devices requires dopant activation with diffusion kept to a minimum. One method considered in device processing is microsecond annealing by pulsed lasers. This is a highly non‐equilibrium process during which intrinsic point defects generated at the surface diffuse into the material and form a variety of defects during cooling‐down. Since the defects lie close to the surface, they may well affect the effective concentration and the formation of leakage currents in pn‐junctions of advanced technologies. These defects may be clusters of intrinsic point defects or contain residual impurities like oxygen or dopants.In this work, a bare n‐type silicon substrate (phosphorus concentration 5 × 1014 cm–3) was annealed with a pulsed laser with maximum temperatures of about 800 K up to 1650 K. The defects remaining after annealing were characterized by deep level transient spectroscopy (DLTS) to obtain their activation energies and capture cross‐sections for majority carriers in n‐type silicon. Additionally, the depth profiles of these defects were measured via a variation of the pulse voltage. The dominating defects found have levels at EC – 0.41 eV, EC – 0.31 eV, EC – 0.3 eV, EC – 0.22 eV, and EC – 0.17 eV. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gettering of iron in CZ‐silicon by polysilicon layer
Authors: Haarahiltunen A. , Yli‐Koski M. , Talvitie H. , Vähänissi V. , Lindroos J. , Savin H. 
Published: November 2010

AbstractWe have studied iron gettering in intentionally iron contaminated Czochralski silicon wafers with a polysilicon layer. We have compared the gettering effect of the poly‐layer with internal gettering during a slow cooling from a high temperature. The experimental results show that the gettering efficiency of the polysilicon layer is stronger than internal gettering by bulk micro defects. In addition, the results reveal that after iron contamination and following surface cleaning, the polysilicon layer remains as a significant contamination source compared to a bare silicon surface. We also suggest a model for polysilicon gettering, which we use to analyze the dominant gettering mechanism under various gettering conditions (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Atomic‐layer‐deposited Ir thin film as a novel diffusion barrier layer in Cu interconnection
Authors: Lim Yong Hwan , Yoo Hana , Choi Bum Ho , Lee Jong Ho , Lee Ho‐Nyun , Lee Hong Kee 
Published: November 2010

AbstractAtomic‐layer‐deposited iridium (Ir) thin films were successfully grown on a silicon substrate using Ir(EtCp)(COD) and oxygen as precursors between 240 and 420 °C. The optimal temperature range for the formation of a smooth and uniform Ir thin film was obtained. At 330 °C, specific ALD process conditions were found to yield a smooth Ir thin film with a thickness of 12 nm. The growth mechanism of ALD iridium thin films was investigated as a function of deposition cycle. In the early stage of ALD growth, Ir firstly nucleated after 100 cycles and continuous films of Ir fully covered the silicon substrate after 300 deposition cycles. These results indicate that the Ir ALD process has a long incubation period in contrast with other general ALD processes (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Anomalous temperature behaviour of band to band electroluminescence in silicon solar cells
Authors: Klossek A. , Arguirov T. , Mchedlidze T. , Kittler M. 
Published: November 2010

AbstractA temperature dependence of intensity for band to band (BB) luminescence of a solar cell excited by constant current in forward biasing was investigated. The obtained temperature dependence is untypical for silicon, i.e. the intensity of the BB luminescence increases with temperature. We analyse our results in view of thermally induced change of excess carrier concentration. Two temperature dependent nonradiative recombination processes limit the carrier concentration. One is the recombination in the bulk, mediated by deep impurity levels and the other is the surface recombination. The surface recombination limits the minority carrier diffusion length to the thickness of the solar cell. We show that the interference of both recombination processes causes the effective lifetime to increase upon increasing temperature. Thereby the deep level mediated recombination dominates at high temperature, whilst the surface recombination is dominant at low temperatures. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantitative analysis of impurities in solar‐grade Si by photoluminescence spectroscopy around 20 K
Authors: Iwai Takaaki , Tajima Michio , Ogura Atsushi 
Published: November 2010

AbstractWe report details about the quantitative analysis of B and P impurities in the concentration range between 1 × 1014 and 1 × 1017 cm–3 by photoluminescence (PL) in solar‐grade Si (SOG‐Si). The intensity ratio of impurity‐bound exciton (BE) to free exciton (FE) at 4.2 K was used as a measure of the impurity concentration in the range between 5 × 1010 and 1 × 1015 cm–3 in the standard PL method. We raised the sample temperature to enhance the FE emission, which enabled us to extend the concentration range higher. The sample temperature was accurately determined from the FE‐line shape. We deduced a formula for the determination of the B and P concentrations in the higher range from the BE/FE ratio and the sample temperature (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Design of three‐component one‐dimensional photonic crystals with tuning of optical contrast and regions of transparency
Authors: Perova Tatiana S. , Tolmachev Vladimir A. , Baldycheva Anna 
Published: November 2010

AbstractThis paper is focused on the design and optical characterization of the three‐component tunable photonic crystal structures based on grooved silicon, serving as one‐dimensional (1D) photonic crystal (PC), with additional regular layer. The manipulation of the optical contrast to a high degree of precision by varying the thickness and refractive index of the additional third layer is obtained. The principle of suppression of the reflection bands and replacing them with regions of transparency is demonstrated for a high contrast 1D PC for the first time. The regions of transparency obtained show a high transmission value (> 0.99) and a substantial band width. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)