bluuebunny/crossref_metadata_2025_split huggingface dataset:
Barrier and self‐healing coating with fluoro‐organic compound for zinc
Authors: Yabuki A. , Kaneda R. 
Published: April 2009

AbstractThe barrier and self‐healing abilities of a corrosion‐protective coating with a fluoro‐organic compound for zinc was investigated. Several types of fluoro‐organic compounds, having different terminal groups and various numbers of carbon atoms, were coated on a pure zinc plate by dip coating. A fluoro‐organic compound having the terminal group of COF showed excellent barrier resistance, which increased as the number of carbon atoms in the compound increased. The optimal conditions — concentration of fluoro‐organic compound in the solution and the pH of the solution — were determined for coating, based on those that demonstrated more ability than chromate conversion coating. Monitoring the corrosion resistance of a scratched specimen in corrosive solution and observing the surface appearance of the specimen after the corrosion test confirmed the self‐healing ability of the coating with the fluoro‐organic compound. The fluoro‐organic coating had excellent self‐healing ability — equivalent to that of a chromate conversion coating. The self‐healing effect of the coating appeared to be due to the release of the fluoro‐organic compound as a result of the pH increase caused by cathodic reaction in the corrosion process, and the formation of a film on the defect.
Electrochemical corrosion behavior of Al–Si alloy composites reinforced with in situ TiB2 particulate
Authors: Sun H. H. , Chen D. , Li X. F. , Ma N. H. , Wang H. W. 
Published: April 2009

AbstractUnderstanding the corrosion behavior of TiB2p‐reinforced aluminum matrix composites is crucial for their development as effective composites. In this work, corrosion characteristics of in situ TiB2 particulate reinforced Al–Si alloy (A356) composite after T6 treatment are investigated by electrochemical techniques. The electrochemical impedance spectroscopy (EIS) reveals that the protection of nature film for the composites is worse than that for A356 alloy. Polarization experiments testify that the composites are susceptible to corrosion compared with their matrix alloys. Moreover, the corrosion resistance of the composites markedly decreases with increase in the TiB2 content. The observations of the corrosion morphologies after polarization test show that the corrosion primarily occurs at the interdendritic sites with a large amount of TiB2 particulates. Corrosion progress continues into the composite inner along the regions of α‐Al dendrite. The poor corrosion resistant properties of the composites are considered primarily due to the galvanic corrosion between noble TiB2 reinforcements and more active aluminum matrix, as well as the weak protection of the defective nature film on the composite.
Effects of Hf content and immersion time on electrochemical behavior of biomedical Ti‐22Nb‐xHf alloys in 0.9% NaCl solution
Authors: Wang B. L. , Zheng Y. F. , Zhao L. C. 
Published: April 2009

AbstractThe aim of this study was to investigate the effects of Hf content and immersion time on the electrochemical corrosion behavior of the Ti‐22Nb‐xHf (x = 0, 2, 4, and 6 at%) alloy samples in 0.9% NaCl solution at 37 °C and neutral pH range, utilizing the potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. From the polarization curves, all these alloys exhibited typical passive behavior, which was indicated by a wide passive region without the breakdown of the passive films and low corrosion current densities. In addition, the values of the corrosion current densities and passive current densities decreased with increase in the Hf content. The EIS results, fitted by RS(QPRP) model, exhibited capacitive behavior (high corrosion resistance) with phase angles closed to −80° and high impedance values at low and medium frequencies, indicating the formation of a highly stable film on these alloys in the test solution. The resistance of the passive films improved with increase in the Hf content and immersion time. All these observations suggested a more noble electrochemical behavior of the Ti‐22Nb‐xHf alloys compared to the Ti‐Nb binary alloy.
Chloride threshold for corrosion of galvanized reinforcement in concrete exposed in the mexican Caribbean
Authors: Maldonado L. 
Published: April 2009

AbstractThe time of incubation (TI) and chloride threshold (CT) necessary to initiate corrosion of reinforcement steel are crucial variables to predict the useful life of an infrastructure in any model. For black steel there is a great amount of data in the bibliography. However, for galvanized steel, is very scarce and in tropical climates no data exist. In this research, CT and TI were determined for galvanized steel embedded in concretes with water/cement (w/c) ratios of 0.4, 0.5, 0.6, and 0.7. The samples were corroded under natural conditions in the north coast of the Yucatan Peninsula for nine years. The results show that galvanized reinforcement can resist chloride levels 2.6–3 times higher than black steel, even in poor quality concretes. Likewise, it was possible to observe that TI for galvanized steel is twice that of black reinforcement, and so the former offers the possibility of extending the useful life of structures.
Current and future corrosion challenges for a reliable and sustainable development of the chemical, refinery, and petrochemical industries
Authors: Ropital F. 
Published: April 2009

AbstractThe chemical, refinery, and petrochemical industries are facing new challenges in order to develop more environment friendly processes and to manufacture “green” products. Corrosion management is an essential element for the development of a sustainable industrial society, including issues such as the selection and development of corrosion resistant materials, coatings, and environment friendly inhibitors. In this paper, some specific challenges will be discussed. In the chemical industry, the replacement of volatile and toxic solvents by green ones such as supercritical water processes, ionic liquid, or the use of carbon dioxide as an alternative solvent, requires specific corrosion management policies. Another issue for the refinery industry concerns new feedstocks such as opportunity crudes containing corrosive naphthenic acids or the transformation of biomass feed into bio‐oils and biomaterials. Synthetic gas is also becoming a crucial intermediate in natural gas, coal or biomass to hydrocarbon liquids (XTL) processes. Other environmental aspects are the limitation of green house gas (GHG) release from the plants by implementation of CO2 capture processes and the environment friendly management of water including more restrictive steps concerning its disposal. The implementation of advanced inspection and corrosion control management is also a major element of progress for a sustainable development of the chemical, refinery, and petrochemical industries.
Electrochemical corrosion behavior of biomedical Ti–22Nb and Ti–22Nb–6Zr alloys in saline medium
Authors: Wang B. L. , Zheng Y. F. , Zhao L. C. 
Published: April 2009

AbstractThe aims of this study were to investigate the effects of Zr addition and potentiodynamic polarization on the microstructure and corrosion resistance of Ti–22Nb and Ti–22Nb–6Zr alloy samples. The corrosion tests were carried out in 0.9% NaCl at 37 °C and neutral pH value, utilizing the OCP, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) techniques. The results of XRD and optical microscopy indicated that the addition of Zr stabilized the β phase, which plays a crucial role in the corrosion resistance improvement of the Ti–22Nb–6Zr alloy. From the polarization curves, it can be seen that the alloys exhibited a wide passive region without the breakdown of the passive films and also low corrosion current densities. In addition, the values of the corrosion current densities and passive current densities decreased with the addition of 6 at% Zr into the Ti–22Nb alloy. The EIS results of these two alloy samples after 1‐h immersion in 0.9% NaCl solution, and being fitted by RS(QPRP) model, suggested that the corrosion resistance of the passive films improved with the addition of Zr and only a single passive film formed on the surfaces. However, two time constants were observed for the Ti–22Nb and Ti–22Nb–6Zr alloy samples after potentiodynamic polarization, the spectra of which can be fitted using the Rs(Qo(Ro(QbRb))) model. In addition, the corrosion resistance of the two alloy samples was reinforced significantly because of polarization when compared to the immersed samples. All these observations suggested a nobler electrochemical behavior of the titanium alloys with the addition of Zr element and after polarization.
Fyn kinase activity is required for normal organization and functional polarity of the mouse oocyte cortex
Authors: Luo Jinping , McGinnis Lynda K. , Kinsey William H. 
Published: April 2009

AbstractThe objective of the present study was to determine whether Fyn kinase participated in signaling events during sperm–egg interactions, sperm incorporation, and meiosis II. The functional requirement of Fyn kinase activity in these events was tested through the use of the protein kinase inhibitor SKI‐606 (Bosutinib) and by analysis of Fyn‐null oocytes. Suppression of Fyn kinase signaling prior to fertilization caused disruption of the functional polarity of the oocyte with the result that sperm were able to fuse with the oocyte in the immediate vicinity of the meiotic spindle, a region that normally does not allow sperm fusion. The loss of functional polarity was accompanied by disruption of the microvilli and cortical granule‐free zone that normally overlie the meiotic spindle. Changes in the distribution of cortical granules and filamentous actin provided further evidence of disorganization of the oocyte cortex. Rho B, a molecular marker for oocyte polarity, was unaffected by suppression of Fyn activity; however, the polarized association of Par‐3 with the cortex overlying the meiotic spindle was completely disrupted. The defects in oocyte polarity in Fyn‐null oocytes correlated with a failure of the MII chromosomes to maintain a position close to the oocyte cortex which seemed to underlie the above defects in oocyte polarity. This was associated with a delay in completion of meiosis II. Pronuclei, however, eventually formed and subsequent mitotic cleavages and blastocyst formation occurred normally. Mol. Reprod. Dev. 76: 819–831, 2009. © 2009 Wiley‐Liss, Inc.
Immunocontraceptive potential of the Ig‐like domain of Izumo
Authors: Wang Min , Lv Zhengmei , Shi Jianli , Hu Yanqin , Xu Chen 
Published: April 2009

AbstractIn the recently published article by Wang et al. [DOI: 10.1002/mrd.21027], Figure 6 was incorrect. The version printed in the original article, which is identical to Figure 3A, was submitted in error. The correct version of Figure 6 is herein reprinted.
Improved Bell's method for the stability analysis of slopes
Authors: Zheng Hong , Tham Leslie George 
Published: April 2009

AbstractA new procedure based on the approximation to the total normal pressure along the slip surface is developed to compute the factor of safety of slopes for slip surfaces of all shapes. By taking the whole sliding body, instead of an individual slice, as the loaded object, all the equilibrium equations are formulated according to the three‐moment equilibrium conditions rather than the two force equilibrium conditions and one‐moment equilibrium condition. The system of nonlinear equations deduced in this way is well‐scaled and enjoys excellent numerical properties such as the existence of solution with a positive factor of safety, a nearly unlimited scope of convergence and a rapid convergence rate associated with the Newton method. In the case of ϕu =0—the situation where no drainage and no consolidation are involved, furthermore, the system has a unique solution and the factor of safety has an explicit expression. Some typical examples are analyzed to demonstrate the numerical properties of the proposed procedure. Copyright © 2009 John Wiley & Sons, Ltd.
The SPH equations for fluids
Authors: Vaughan G. L. 
Published: April 2009

AbstractExisting smoothed particle hydrodynamics (SPH) formulations for simulating continuous fluids have errors that may be divergent and it has been known for some time that the SPH equations do not satisfy low‐order polynomial completeness conditions. Here SPH equations are derived that have convergent error terms and a correction method is presented for enforcing low‐order polynomial completeness irrespective of how many completeness conditions are required. Discretization is achieved through division of the model domain, in its initial state, into sub‐domains that have Lagrangian boundaries. It is shown that boundary integrals appearing in one derivation of the SPH equations may be treated as a convergent error. In simulations of basic fluid flows convergence and zeroth‐order completeness are demonstrated, but significant instabilities and a failure to conserve energy are observed. Copyright © 2009 John Wiley & Sons, Ltd.
A best approximation for the solution of one‐dimensional variable‐coefficient Burgers' equation
Authors: Li Fuxiang , Cui Minggen 
Published: April 2009

AbstractIn this article, an iterative method for the approximate solution to one‐dimensional variable‐coefficient Burgers' equation is proposed in the reproducing kernel space W(3,2). It is proved that the approximation wn(x,t) converges to the exact solution u(x,t) for any initial function w0(x,t) ε W(3,2), and the approximate solution is the best approximation under a complete normal orthogonal system $ \{\bar{\psi}_{i}\}^{\infty}_{i=1} $. Moreover the derivatives of wn(x,t) are also uniformly convergent to the derivatives of u(x,t).© 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009
Numerical simulations for two‐dimensional incompressible Navier‐Stokes equations with stochastic boundary conditions
Authors: Lu Junxiang , Ma Yichen , Kong Fande 
Published: April 2009

AbstractThe article mainly concerns modeling the stochastic input and its propagation in incompressible Navier‐Stokes(N‐S) flow simulations. The stochastic input is represented spectrally by employing orthogonal polynomial functionals from the Askey scheme as trial basis to represent the random space. A standard Galerkin projection is applied in the random dimension to derive the equations in the weak form. The resulting set of deterministic equations is then solved with standard methods to obtain the mean solution and variance of the stochastic velocity. In this article, the main method employs the Hermite polynomial as the basis in random space. Cavity problems are given to demonstrate the process of numerical simulation. Furthermore, Monte‐Carlo simulation method is applied to illustrate the accurate numerical results. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010
Algorithms for vector field generation in mass consistent models
Authors: Flores Ciro , Juárez Héctor , Núñez Marco A. , Sandoval María Luisa 
Published: April 2009

AbstractDiagnostic models in meteorology are based on the fulfillment of some time independent physical constraints as, for instance, mass conservation. A successful method to generate an adjusted wind field, based on mass conservation equation, was proposed by Sasaki and leads to the solution of an elliptic problem for the multiplier. Here we study the problem of generating an adjusted wind field from given horizontal initial velocity data, by two ways. The first one is based on orthogonal projection in Hilbert spaces and leads to the same elliptic problem but with natural boundary conditions for the multiplier. We derive from this approach the so called E–algorithm. An innovative alternative proposal is obtained from a second approach where we consider the saddle–point formulation of the problem—avoiding boundary conditions for the multiplier— and solving this problem by iterative conjugate gradient methods. This leads to an algorithm that we call the CG–algorithm, which is inspired from Glowinsk's approach to solve Stokes–like problems in computational fluid dynamics. Finally, the introduction of new boundary conditions for the multiplier in the elliptic problem generates better adjusted fields than those obtained with the original boundary conditions. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010
Advances in liquid crystalline conjugated polymers
Authors: Akagi Kazuo 
Published: April 2009

AbstractWe review advances in liquid crystalline (LC) conjugated polymers by focusing on (i) ferroelectric and (ii) photoresponsive LC conjugated polymers. In Part 1, LC polyphenylene derivatives were synthesized through substitution of fluorine‐containing chiral LC groups into side chains. Poly(para‐phenylene) [P1] and poly(meta‐phenylene) [P2] derivatives showed chiral smectic C phases responsible for ferroelectricity. They exhibited quick response to electric field, giving switching times of <1 s between two bistable states. The spontaneous polarization (PS) of P2 remained unchanged even after the electric field became zero, affording the residual polarization (PR) whose value was the same as that of PS. This indicates that P2 has a potential memory function based on FLC nature. In Part 2, poly(para‐phenylenevinylene) [P5] and poly(bithienylene‐phenylene) [P6] derivatives were synthesized by introducing dithienylethene moieties into side chains. Drastic quenching of fluorescence occurred when the photoresponsive moiety changed from an open form to a closed one upon an irradiation of ultraviolet light. The quenched fluorescence was recovered through a photoisomerization from the closed form to the open one. Macroscopically aligned P6 film exhibited a linearly polarized fluorescence with significant anisotropy. Reversible quenching and emitting behavior in anisotropic fluorescence was controlled by the photochemical switching. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2463–2485, 2009
Poly‐(p‐phenylene vinylenes) with pendent 2,4‐difluorophenyl and fluorenyl moieties: Synthesis, characterization, and device performance
Authors: Li Shengbiao , Zhao Ping , Huang Yanqin , Li Tingcheng , Tang Chao , Zhu Rui , Zhao Lei , Fan Quli , Huang Shiqiang , Xu Zushun , Huang Wei 
Published: April 2009

AbstractTo improve efficiency, processability, and stability, three novel poly‐(p‐phenylene vinylenes) (PPVs) derivatives (Pa, Pb, and Pc) with pendent 2,4‐difluorophenyl and fluorenyl moieties were synthesized via Gilch reaction. Their structures were characterized by 1H NMR, 13C NMR, and ELEM. ANAL. Compared with those of PPV and MEH‐PPV, the absolute quantum efficiencies of these polymers showed remarkable improvement (measured at 38.7, 37.2, and 20.3%, respectively), which can be attributed to the presence of twisted multiaryl segments and fluorine atoms. TGA revealed that the inflection temperatures of their thermal decomposition curves were above 400 °C. Double‐layered electroluminescent devices with these polymers as light‐emitting layers [ITO/PEDOT:PSS/Polymer/Ba/Al] showed peak emissions at 493/515, 503, and 600 nm and maximum luminance of 2700, 450, and 4700 cd/m2 for Pa, Pb, and Pc, respectively, with onset voltages of ∼4 V. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2500–2508, 2009
Carbon nanotubes decorated with terpyridine‐ruthenium complexes
Authors: Stefopoulos Andreas A. , Pefkianakis Eleftherios K. , Papagelis Konstantinos , Andreopoulou Aikaterini K. , Kallitsis Joannis K. 
Published: April 2009

AbstractSurface functionalization of CNTs (SWCNTs or MWCNTs) with dendronized alkoxy terpyridine‐Ru(II)‐terpyridine complexes has been accomplished using either the “grafting to” or the “grafting from” approaches. Different sets of easily processable hybrid metallo‐CNTs composites have been efficiently synthesized bearing either monomeric or polymeric side chain tpy‐Ru(II)‐tpy dicomplexes. Their characterization through TGA, UV‐Vis, and Raman techniques revealed various modification degrees depending on the methodology employed. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2551–2559, 2009
Synthesis and characterization of novel PDMS nanocomposites using POSS derivatives as cross‐linking filler
Authors: Baumann Theodore F. , Jones Ticora V. , Wilson Thomas , Saab Andrew P. , Maxwell Robert S. 
Published: April 2009

AbstractWe report the synthesis and characterization of novel elastomeric nanocomposites containing polyhedral oligomeric silsesquioxanes (POSS) as both the cross‐linker and filler within a polydimethylsiloxane (PDMS) polymer matrix. These polymer composites were prepared through the reaction of octasilane‐POSS (OS‐POSS) with vinyl‐terminated PDMS chains using hydrosilylation chemistry. In addition, larger super‐POSS cross‐linkers, consisting of two pendant hepta(isobutyl)POSS molecules attached to a central octasilane‐POSS core, were also used in the fabrication of the PDMS composites. The chemical incorporation of these POSS cross‐linkers into the PDMS network was verified by solid‐state 1H magic angle spinning NMR. Based on dynamic mechanical analysis, the PDMS nanocomposites prepared with the octafunctional OS‐POSS cross‐linker exhibited enhanced mechanical properties relative to polymer systems prepared with the tetrafunctional TDSS cross‐linker at equivalent loading levels. The observed improvements in mechanical properties can be attributed to the increased dimensionality of the POSS cross‐linker. The PDMS elastomers synthesized from the larger super‐POSS molecule showed improved mechanical properties relative to both the TDSS and OS‐POSS composites due to the increased volume‐fraction of POSS filler in the polymer matrix. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2589–2596, 2009
Control of molecular aggregation in symmetrically substituted π‐conjugated bulky poly(p‐phenylenevinylene)s and their copolymers
Authors: Resmi R. , Amrutha S. R. , Jayakannan M. 
Published: April 2009

AbstractA new series of symmetrically substituted bulky PPV‐copolymers based on poly(bis‐2,5‐(2‐ethylhexyloxy)‐1,4‐phenylenevinylene) (BEH‐PPV) bearing tricyclodecane (TCD) pendants were synthesized to study the effect of chain aggregation in the π‐conjugated polymer backbone. The composition of the copolymers was varied up to 100 mol % and the structures of the copolymer were confirmed by NMR and FTIR. The molecular weights of the copolymers were obtained as Mw = 11,500–1,78,800 depending on the TCD‐incorporation in BEH‐PPV. The origin of the π‐aggregation was investigated using mixture of solvents (polar or nonpolar) or temperature as external stimuli. Absorption, photoluminescence, and time‐resolved fluorescence decay techniques were employed as tools to trace molecular aggregation in solution and solid state. The TCD‐substituted bulky copolymers showed almost twice the enhancement in photoluminescence compared with that of BEH‐PPV. Solvent‐induced aggregation studies of copolymers revealed the existence of strong molecular aggregation in BEH‐PPV compared with that of bulky copolymers. Variable temperature studies further evidence for the reversibility of molecular aggregation on heating/cooling cycles and showed isosbetic points with respect to free and aggregated polymer chains. Time‐resolved fluorescent studies confirmed the existence of free and aggregated π‐conjugated species with a life time of 0.1 to 1.0 ns. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2631–2646, 2009