bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanic treatment of fastener holes: The influence of compressive residual stress on the corrosion behaviour of aluminium alloys
Authors: Schneider J. , Haindl H. 
Published: September 2008

AbstractCorrosion has a significant impact on the life cycle cost of military aircraft. Fleet experiences show that structural areas around joining elements (rivets, bolts) and faying surfaces are particularly sensitive to corrosion. During the repair currently performed the corrosion usually is blended out, the surface protection applied, the fastener inserted and a new top coat applied. Blending out corrosion often results in a reduction of fatigue life. To restore fatigue life the induction of compressive stress in the area affected is common practice. It is generally accepted that the induction of compressive residual stress extends fatigue life but its impact on the overall corrosion behaviour of alloys is discussed controversially in the literature. For this reason the influence of compressive residual stress on the corrosion behaviour was investigated in a joint experimental project. The compressive residual stress was introduced in different ways on laboratory scale and the specimens artificially weathered to simulate the effect of corrosion.
A study of electrical chloride extraction of iron artifacts
Authors: Lin Yantao , Liu Jianguo 
Published: September 2008

AbstractThe chloride extraction rule of iron artifacts was studied by electrical methods. The effect of the current and potential value on the desalination result of simulated iron artifacts was studied through the galvanostatic and potentiostatic experiments; the ingredients of the rust before and after treatments were also analyzed by the X‐ray diffraction (XRD). It has been found that the optimal current density was between −0.50 and −0.75 mA/cm2 and the optimal potential was between −1.175 and −1.200 V. The phase of the samples rusts transformed after treatment, as well as the anti‐corrosion performance improved.
Modification and Grafting of Multi‐Walled Carbon Nanotubes with Bisphenol‐A‐polycarbonate
Authors: Mormann Werner , Lu Yong , Zou Xuena , Berger Ralf 
Published: September 2008

AbstractMulti‐walled carbon nanotubes (MWNT) were oxidized with nitric acid and resulting carboxy groups were transformed to amino groups with a diamine under microwave irradiation. Grafting of bisphenol‐A‐polycarbonate onto carboxy‐ and amino‐functional MWNT through transesterification or aminolysis resulted in weight increase up to 300%. The morphology of functionalized and grafted MWNTs was investigated with scanning force microscopy (SFM) and transmission electron microscopy (TEM). Depending on the type of functionalisation and the extent of grafting different morphologies were observed. Aminofunctional MWNT‐g‐PCs showed more “ball‐like” or irregular protrusions of grafted PC. Carboxyfunctional MWNT‐g‐PCs were more smoothly covered with PC.magnified image
Investigation of Chain Dynamics in Poly(n‐alkyl methacrylate)s by Solid‐State NMR: Comparison with Poly(n‐alkyl acrylate)s
Authors: Gaborieau Marianne , Graf Robert , Spiess Hans Wolfgang 
Published: September 2008

AbstractPnAMAs exhibit a local nanophase separation associated with intriguing chain dynamics (Macromol. Chem. Phys. 2005, 206, 142). PnAMAs of high molar mass, as determined by SEC and MHKS parameters, were investigated in the melt with a recently‐developed solid‐state NMR method (NOE with dipolar filter; Solid State Nucl. Magn. Res. 2005, 28, 160). The correlation times are assigned to the relaxation of the alkyl nanodomains, as coupled motions of the main chain and hindered local modes in the side chain. Comparison with poly(n‐alkyl acrylates) shows a higher anisotropy of the main chain motions and a better organized local nanophase separation in PnAMAs.magnified image
Comparison of Three Different Click Reaction Methods for the Synthesis of Fluorene‐Based Polymers and Performance in Quasi‐Solid‐State DSSCs
Authors: Karim Md. Anwarul , Cho Young‐Rae , Park Jin Su , Ryu Tae In , Lee Myung Jin , Song Myungkwan , Jin Sung‐Ho , Lee Jae Wook , Gal Yeong‐Soon 
Published: September 2008

AbstractThe three different methods of click reaction has been used to synthesize fluorene‐based click polymers and compared its effect on polymer electro‐optical properties as well as photovoltaic performances in DSSCs. The DSSCs devices with configuration of SnO2:F/TiO2/N719 dye/quasi‐solid‐state electrolyte/Pt devices were fabricated using these click polymers as a quasi‐solid‐state electrolyte components. Among the devices, the catalyzed click polymer composed DSSCs device exhibited high power conversion efficiency (PCE) of 4.62% under AM 1.5G illumination. These click polymers are promising materials for device application and the CuI‐catalyst 1,3‐dipolar cycloaddition click reaction is an efficient synthetic methodology.magnified image
Biotin‐, Pyrene‐, and GRGDS‐Functionalized Polymers and Nanogels via ATRP and End Group Modification
Authors: Siegwart Daniel J. , Oh Jung Kwon , Gao Haifeng , Bencherif Sidi A. , Perineau Fabien , Bohaty Andrew K. , Hollinger Jeffrey O. , Matyjaszewski Krzysztof 
Published: September 2008

AbstractFunctionality, one of the key attributes of atom transfer radical polymerization (ATRP), was utilized for the synthesis of well‐controlled polymers functionalized with biotin, pyrene, and peptides. Hydroxy‐functionalized poly(oligo(ethylene oxide) monomethyl ether methacrylate) (HO‐POEOMA) was prepared by AGET ATRP of OEOMA initiated by 2‐hydroxyethyl 2‐bromoisobutyrate in water or in inverse miniemulsion of water/cyclohexane at ambient temperature. HO‐POEOMA was then further functionalized with biotin, pyrene, and GRGDS peptide. In addition, ATRP and click chemistry offered an efficient route for the synthesis of telechelic di‐biotin polymers. These general methods can be applied to the formation of different functional materials conjugated with proteins, dyes, nucleic acids, and drugs.magnified image
Additive Processing of Polymers
Authors: Wendel Bettina , Rietzel Dominik , Kühnlein Florian , Feulner Robert , Hülder Gerrit , Schmachtenberg Ernst 
Published: September 2008

AbstractAdditive processing technologies are rapidly growing in all fields of application. A large number of scientific publications were investigated in order to provide a comprehensive overview of rapid prototyping methods for polymers and their applications, of currently available materials and research concerning additive processes. The current problems of additive processes are described, together with their potential solutions. Furthermore, this article delivers an insight into possible future trends of additive technologies.magnified image
Sigmoidal Chemorheological Models of Chip‐Underfill Materials Offer Alternative Predictions of Combined Cure and Flow
Authors: Love Brian J. , Teyssandier Fabien , Sun Yang Y. , Wong Ching P. 
Published: September 2008

AbstractPrior rheology results on chip‐underfill epoxy resins have been re‐analyzed by a sigmoidal model that contains three variable physical parameters, including the terminal cured viscosity of the gel, an induction or dwell time and a time factor associated with the speed of conversion as viscosity undergoes large dynamic changes during rapid crosslinking. The analyses were conducted with resins that were originally cured between 150 and 180 °C and show obvious non‐linearity, even on a semi‐log plot of dynamic viscosity. The sigmoidal models more accurately represent a wider range of dynamic viscosity than power‐law‐based rheological models, which are both more common and more generally accepted for practical application. If total flow is the critical design parameter in terms of chip underfill, perhaps these alternative sigmoidal models need to be more thoroughly evaluated to gauge their practical use and validity.magnified image
Electrospun Silica—Polybenzimidazole Nanocomposite Fibers
Authors: von Graberg Till , Thomas Arne , Greiner Andreas , Antonietti Markus , Weber Jens 
Published: September 2008

AbstractA new route for the manufacturing of silica/poly(benzimidazole) (PBI) nanocomposites fibers is described. PBI was synthesized via melt polycondensation and polycondensation in poly(phosphoric acid). Solutions of PBI and silica nanoparticles in N,N‐dimethylacetamide (DMAc) were electrospun to fibers and non‐wovens. The resulting materials were analyzed by ATR‐IR spectroscopy, small‐angle X‐ray scattering (SAXS) and nitrogen sorption measurements. The non‐wovens could be processed towards dense, cross‐linked membranes by hot pressing and treatment with p‐xylylene dichloride.magnified image
Highly Fluorescent Conjugated Copolymers Containing Dithieno[3,2‐b:2′,3′‐d]pyrrole
Authors: Zhang Wei , Li Jun , Zhang Bao , Qin Jingui 
Published: September 2008

AbstractThree copolymers that incorporate dithieno[3,2‐b:2′,3′‐d]pyrrole with fluorene, carbazole, or pyridine have been prepared by Suzuki reaction and characterized by NMR spectroscopy and GPC. A new homopolymer of dithieno[3,2‐b:2′,3′‐d]pyrrole was also synthesized for the comparison of their structure–property relationships. Their thermal, optical, and electrochemical properties have been investigated. All the polymers exhibit good thermal stability with decomposition temperatures around 400 °C. The fluorescence quantum efficiencies of all these polymers in solution are in the range of 33.5–55.5%. The copolymers also show high film fluorescence quantum efficiencies of about 20% while the fluorescence of the homopolymer film is almost quenched.magnified image
Acyclic Triene Metathesis Polymerization with Chain‐Stoppers: Molecular Weight Control in the Synthesis of Branched Polymers
Authors: Fokou Patrice A. , Meier Michael A. R. 
Published: September 2008

AbstractThe synthesis of branched macromolecules from renewable resources via olefin metathesis is described. We observed that it is possible to control the molecular weight during the acyclic triene metathesis (ATMET) of a triglyceride by the application of methyl acrylate as a chain stopper for this straightforward one step one pot polymerization. The resulting branched materials were characterized by GPC, NMR as well as ESI‐MS and the combination of these techniques provided valuable insights into the polymer structure as well as occurring side reactions during this olefin metathesis polymerization reaction.magnified image
Synthesis of Seven‐Arm Poly(vinyl pyrrolidone) Star Polymers with Lysozyme Core Prepared by MADIX/RAFT Polymerization
Authors: McDowall Lyndall , Chen Gaojian , Stenzel Martina H. 
Published: September 2008

AbstractA poly(vinyl pyrrolidone) (PVP) seven‐arms star polymer with lysozyme core was synthesized by conjugating linear N‐succinimidyl ester terminated PVP polymer to lysozyme. Reactive PVP polymers were synthesized using a MADIX/RAFT agent functionalized with N‐succinimidyl ester. The polymerization of N‐vinyl pyrrolidone proceeded in a living fashion up to more than 90% conversion reaching molecular weight of up to 33 000 g · mol−1 with narrow molecular weight distributions. The PVP polymer was conjugated to lysozyme resulting in the attachment of seven PVP polymers to one lysozyme core. While the reaction was found to be complete when using low‐molecular weight PVP, some by‐products with less than seven arms were observed when using PVP with a molecular weight of 33 000 g · mol−1.magnified image
Controlling Fusion and Aggregation in Polymersome Dispersions
Authors: Smart Thomas P. , Fernyhough Christine , Ryan Anthony J. , Battaglia Giuseppe 
Published: September 2008

AbstractThe effects of addition of poly(ethylene oxide) (PEO) to poly(ethylene oxide)16‐block‐poly(butylene oxide)22 (EB1) polymersome dispersions has been studied. Aggregation and membrane fusion between polymersomes were observed with great control of the outcome by varying PEO molecular weight. Small‐scale fusion of 2 to 3 polymersomes was seen with low‐molecular‐weight PEO, whilst large‐scale aggregation occurred above a critical PEO molecular weight of 4 000 Da. The resulting highly porous EB1‐PEO aggregate shows great promise for applications in cell entrapment for transport and delivery, and as a three‐dimensional scaffold for use in tissue engineering.magnified image
Mechanical Characterization of Motor Proteins: A Molecular Dynamics Approach
Authors: Aprodu Iuliana , Soncini Monica , Redaelli Alberto 
Published: September 2008

AbstractA new approach, based on molecular dynamics, is presented to measure the mechanical properties of motor proteins, which are important for accomplishing their intracellular functions. Two different set‐ups were designed to mimic the optical tweezers and surface force apparatus experiments. The results obtained show that the stiffness and elastic modulus of kinesin motor domain are 377 pN · nm−1 and 0.17 GPa, respectively, while the myosin motor domain is characterized by a stiffness of 271 pN · nm−1 and an elastic modulus of 0.26 GPa. These results suggest that the source of the very low stiffness detected for full‐length molecules is located outside of the globular part of the proteins.magnified image
A differential constraint approach to obtain global stability for radiation‐induced double‐diffusive convection in a porous medium
Authors: Hill Antony A. 
Published: September 2008

AbstractThe stability of double‐diffusive porous convection with a concentration‐based internal heat source is studied. Owing to the significant sensitivity of standard energy method, a highly desirable reduction in the number of required coupling parameters is achieved through the novel energy method of van Duijn et al. (Environmental Mechanics: Water, Mass and Energy Transfer in the Biosphere. American Geophysical Union: Washington, DC, 2002; 155–169). This approach incorporates the Darcy equation as a differential constraint, and has been shown by van Duijn et al. to generally yield sharper nonlinear results. Owing to the widespread use of coupling parameters in analysing porous media stability, this result strongly advocates the differential constraint approach for obtaining optimal nonlinear stability thresholds. Copyright © 2008 John Wiley & Sons, Ltd.
Generation of viscous grids at ridges and corners
Authors: Aubry Romain , Löhner Rainald 
Published: September 2008

AbstractAn extension of Löhner (AIAA‐93‐3348‐CP, 1993) for the generation of high aspect ratio volume grids on surfaces with ridges and corners is presented for Reynolds‐averaged Navier–Stokes computations. Multiple point normals are introduced along ridges and corners. The original technique generates a semi‐structured boundary layer of prismatic elements growing along point normals. Therefore, extra degenerated faces must be introduced to take into account the multiple growth curves at ridges and corners and produce a valid topological surface triangulation. The major task of the algorithm consists in recovering conformity in the surface mesh triangulation, which has been lost due to the introduction of the virtual faces. The procedure relies on a topological taxonomy of an arbitrary combination of concave and convex ridges. Each case is highlighted in detail. Special boundary conditions such as symmetry planes and periodic boundary conditions are also handled. Several complex geometries have been chosen to illustrate the proposed procedure, and timings are given, showing that the new module does not place any extra burden on the previous semi‐structured approach. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis, photocrosslinking characteristics, and biocompatibility evaluation of N‐vinyl pyrrolidone/polycaprolactone fumarate biomaterials using a new proton scavenger
Authors: Sharifi Shahriar , Mirzadeh Hamid , Imani Mohammad , Ziaee Farshid , Tajabadi Maryam , Jamshidi Ahmad , Atai Mohammad 
Published: September 2008

AbstractPhotocrosslinkable and biodegradable polymeric networks were formulated based on N‐vinyl pyrrolidone‐poly(ε‐caprolactone fumarate) (NVP/PCLF) compositions for hard tissue engineering applications using a new proton scavenger, propylene oxide (PO). The synthesized macromers were obtained as a white clear paste with no colorization. The obtained macromers were thoroughly characterized using spectroscopic (NMR and FT‐IR) and chromatographic (gel permeation chromatography (GPC)) techniques. Photocrosslinking of the PCLF/NVP compositions was achieved using camphorquinone and dimethyl toluidine (DMT) as a photoinitiator system. The cytocompatibility of the macromers and their corresponding networks were evaluated via MTT assay. Characterization of the networks indicated the importance of NVP content on the network properties. Sol fraction studies indicated that more than 90% of the PCLFs were crosslinked over the studied range of PCLF/NVP compositions; however most of the NVP above a stoichiometric ratio of one NVP to fumerate unit remained unreacted. It was also found that in the concentrations more than 10% NVP, the unreacted NVP monomer neither participated in the crosslinking reaction nor homopolymerized to poly(vinyl pyrrolidone) (PVP). The elastic modulus (G′) and estimated molecular weight between crosslinks also confirmed that at the higher NVP content the PCLF photocrosslinking was hindered. Copyright © 2008 John Wiley & Sons, Ltd.
The Human Protein Atlas—a tool for pathology
Authors: Pontén F , Jirström K , Uhlen M 
Published: September 2008

AbstractTissue‐based diagnostics and research is incessantly evolving with the development of new molecular tools. It has long been realized that immunohistochemistry can add an important new level of information on top of morphology and that protein expression patterns in a cancer may yield crucial diagnostic and prognostic information. We have generated an immunohistochemistry‐based map of protein expression profiles in normal tissues, cancer and cell lines. For each antibody, altogether 708 spots of tissues and cells are analysed and the resulting images and data are presented as freely available in the Human Protein Atlas (www.proteinatlas.org). The new version 4 of the atlas, including more than 5 million images of immunohistochemically stained tissues and cells, is based on 6122 antibodies, representing 5011 human proteins encoded by approximately 25% of the human genome. The gene‐centric database includes a putative classification of proteins in various protein classes, both functional classes, such as kinases or transcription factors and project‐related classes, such as candidate genes for cancer or cardiovascular diseases. For each of the internally generated antibodies, the exact antigen sequence is presented, together with a visualization of application‐specific validation data, including a protein array assay, western blot analysis, immunohistochemistry and, in most cases, immunofluorescent‐based confocal microscopy. The updated version also includes new search algorithms to allow complex queries regarding expression profiles, protein classes and chromosome location. Thus, the presented Human Protein Atlas provides a resource for pathology‐based biomedical research, including protein science and biomarker discovery. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Effect of fumed silica nanoparticles on glass fiber filled thermotropic liquid crystalline polymer composites
Authors: Park Sang Ki , Kim Seong Hun , Hwang Jin Taek 
Published: September 2008

AbstractGlass fiber filled thermotropic liquid crystalline polymer (gLCP)/silica composites were prepared by melt compounding. The total torque of the gLCP/silica composites decreased and the melt flow index increased with increasing silica content, which indicates that the fumed silica nanoparticles act as good processing aids and enhance the processing behavior of gLCP/silica composites. The rheological properties of the gLCP/silica composites were significantly dependent on the silica content. The complex viscosity and storage modulus (G′) of the gLCP/silica composites decreased with increasing silica content. This was attributed to the ability of the silica nanoparticles to break the glass fiber–glass fiber interactions in the gLCPs. The storage modulus and loss modulus (G″) of the gLCP/silica composites increased with increasing frequency, and the increment was more significant at low frequency. Incorporation of a small quantity of silica nanoparticles improved the thermal stability and mechanical properties of gLCP/silica composites. However, at high silica nanoparticle content the mechanical properties of gLCP/silica composites decreased because of the aggregation of silica nanoparticles. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Structure and conditioning effect on mechanical behavior of poly(vinyl alcohol)/calcium lactate biocomposites
Authors: Sedlarik Vladimír , Galya Tsermaa , Emri Igor , Saha Petr 
Published: September 2008

AbstractThe structural and mechanical characteristics of polymeric biocomposites based on calcium lactate (CL) and either partially (88 mol%) or fully (98 mol%) hydrolyzed poly(vinyl alcohol) (PVA) were studied using optical microscopy, Fourier transform infrared spectroscopy equipped with attenuated total reflectance accessory, water content determination, and differential scanning calorimetry. In addition, the moisture absorption effect on the mechanical properties of the biocomposites was tested in this work. The results reveal that CL is a suitable modifier for both types of PVA. However, a more efficient enhancement of uniform shape and size distribution of CL particles within the PVA matrix was noticed in fully hydrolyzed matrix at low water contents. It is in agreement with glass transition temperature's observations. The samples conditioned at 50% of relative humidity (RH) showed decrease in E modulus and tensile strength in comparison with the material stored below 20% RH. Nevertheless, the enhancement of tensile properties, because of the modification with CL, was still noticeable especially for the partially hydrolyzed PVA‐based biocomposites. The optimum concentration of the modifier was estimated on the basis of the obtained results. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
The school neuropsychology of ADHD: Theory, assessment, and intervention
Authors: Goldstein Sam , Naglieri Jack A. 
Published: September 2008

AbstractAlthough the five‐part diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders Fourth Edition, Text Revision (DSM‐IV‐TR) for attention‐deficit/hyperactivity disorder (ADHD) are behavioral and descriptive in nature, this condition has increasingly been defined as a disorder resulting from impaired behavioral inhibition leading to executive function deficits. Recent research, particularly involving the Planning, Attention, Simultaneous, Successive (PASS) theory offers an understanding of the intellectual and neuropsychological processes implicated in ADHD. We provide an overview of ADHD as a neuropsychological condition; reviews of research on the PASS theory, which provide a process‐based understanding of ADHD; and recommendations for assessment and intervention. The research base summarized here provides support that ADHD have a distinctive profile of PASS processes that is consistent with the cognitive nature of their disorder and that researchers have shown increased academic performance when children are taught to better use planning processes when completing academic tasks. © 2008 Wiley Periodicals, Inc.