bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydrogen‐containing silicone resin as the crosslinking agent of heat‐curable silicone rubber
Authors: Zhao S. , Feng S. 
Published: April 2003

AbstractThe hydrosilation‐cured vulcanizates (HCV) of silicone rubber were prepared by using hydrogen‐containing silicone resin (HSR) as the crosslinking agent. The influences of both the amount and structure of HSR on hydrosilation‐curing silicone rubber (HCSR) were discussed. The results indicate that HSR is a good crosslinking agent for HCSR. The tensile strength, tearing strength, elongation at break, and hardness of the vulcanizates can reach 9.6 MPa, 37.8 kN/m, 870% and 56 SHA, respectively. The aging stability of the vulcanizates can be improved greatly. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3066–3069, 2003
PP–PP‐g‐MAH–Org‐MMT nanocomposites. I. Intercalation behavior and microstructure
Authors: Xu Weibing , Liang Guodong , Wang Wei , Tang Shupei , He Pingsheng , Pan Wei‐Ping 
Published: April 2003

AbstractThe melt‐direct intercalation method was employed to prepare poly(propylene) (PP)–maleic anhydride grafted poly(propylene) (PP‐g‐MAH)–organic‐montmorillonite (Org‐MMT) nanocomposites. X‐ray diffractometry (XRD) was used to investigate the intercalation effect, crystallite size, and crystal cell parameter in these composites. Two kinds of maleated PP, with graft efficiencies of 0.6 and 0.9 wt %, and two sorts of manufacturing processes were used to prepare nanocomposites and then to investigate their effects on intercalation behavior. The results showed that the intercalation effect was enhanced by increasing the content of PP‐g‐MAH, using maleated PP with higher graft efficiency, and adopting the mold process. The crystallite size of nanocomposites perpendicular to the crystalline plane, such as (040), (130), (111), and (041), reached the minimum value when the content of PP‐g‐MAH was 20 wt %. This result indicated that the crystallite size of PP in nanocomposites decreased by proper addition of PP‐g‐MAH. Maximum values in tensile strength (40.2 MPa) and impact strength (24.3 J/m) were achieved when the content of PP‐g‐MAH was 10 and 20%, respectively. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3225–3231, 2003
Compatibilization and toughening of poly(2,6‐dimethyl‐1,4‐phenylene oxide)/polyamide 6 alloy with poly(ethylene 1‐octene): Mechanical properties, morphology, and rheology
Authors: Wang Xiaodong , Feng Wei , Li Hangquan , Jin Riguang 
Published: April 2003

AbstractBlends of a poly(2,6‐dimethyl‐1,4‐phenylene oxide) (PPO)/polyamide 6 (PA 6) alloy toughened with a novel polyolefin elastomer poly(ethylene‐1‐octene) (POE) were prepared via melt extrusion. In order to improve the compatibilization between POE and the PPO/PA 6 alloy, POE was grafted with maleic anhydride (MA), which could react with the amine group of PA 6. The Izod impact strength of the blends exhibited an optimum when the extent of MA grafting of POE was changed, which is an order of magnitude higher than that of the untoughened blends. The morphology revealed that the size of the POE particles decreased with an increasing MA grafting ratio of POE. Studies on the tensile properties and rheology of the blends were also carried out. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3110–3116, 2003
Effect of surface‐modifying macromolecules and membrane morphology on fouling of polyethersulfone ultrafiltration membranes
Authors: Zhang L. , Chowdhury G. , Feng C. , Matsuura T. , Narbaitz R. 
Published: April 2003

AbstractPolyethersulfone (PES) ultrafiltration (UF) membranes with and without surface‐modifying macromolecules (SMMs) were prepared and characterized in terms of the mean pore size and pore‐size distribution, surface porosity, and pore density. The results demonstrated that both the mean pore size and the molecular weight cutoff (MWCO) of the SMM‐modified membranes are lower than those of the corresponding unmodified ones. Membrane fouling tests with humic acid as the foulant indicated that the permeate flux reduction of the SMM‐modified membranes was much less than that of the unmodified ones. Therefore, fouling was more severe for the unmodified membranes. Moreover, the dry weight of the humic acid deposited on the membrane surface was considerably higher for the unmodified membranes. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3132–3138, 2003
Film extrusion and film weldability of poly(lactic acid) plasticized with triacetine and tributyl citrate
Authors: Ljungberg Nadia , Andersson Thorbjörn , Wesslén Bengt 
Published: April 2003

AbstractFilm extrusion and welding of biodegradable polymer films are important processes that must be considered in the development of compostable packaging materials. Film extrusion of poly(lactic acid) (PLA) has proved to be rather difficult because of its brittleness, but the flexibility of PLA can be improved by incorporation of a plasticizer in the material. PLA was plasticized with triacetine (TAc) and tributyl citrate (TbC). The blended materials and neat PLA were film extruded and the films were welded with constant heat (CH) welding. The films were analyzed by means of gas chromatography (GC), dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), gel permeation chromatography (GPC), contact angle measurements, and tensile testing. Storage of the plasticized films resulted in an increased crystallinity and changes in the film properties, rendering CH welding difficult. The welding process had no influence on thermal properties, such as cold crystallization temperature, melting temperature, crystallization temperature, and degree of crystallinity, of neat PLA but caused significant changes in the crystallinity of the plasticized materials. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3239–3247, 2003
Effects of lignin as a filler on properties of soy protein plastics. I. Lignosulfonate
Authors: Huang Jin , Zhang Lina , Chen Fangeng 
Published: April 2003

AbstractA series of biodegradable plastics from soy protein isolate (SPI) and lignosulfonate (LS) with a weight ratio of 0:10 to 6:4 were prepared with 40 wt % glycerol as a plasticizer by compression molding. Their properties were investigated by wide‐angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamical mechanical thermal analysis (DMTA), scanning electron microscopy (SEM), and tensile tests. The results indicated that the introduction of a moderate LS content from 30 to 40 parts in the blends could simultaneously enhance the tensile strength, elongation, and Young's modulus of soy protein plastics alone. Studies of the water sensitivity of the materials suggested that the strong interaction between LS and SPI could restrict the effect of water on the swelling and the damage of the materials, resulting in lower water absorption. The improvement of the properties was attributed mainly to the existence of the beneficial microphase separation and the formation of crosslinked structures because of the introduction of LS into soy protein plastics. Therefore, a model of a crosslinked network formed from SPI molecules with an LS center was established based on the existence of strong physical interactions between LS and SPI. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3284–3290, 2003
Assessment questionnaire on the personal style of the therapist PST‐Q
Authors: Fernández‐Álvarez Héctor , García Fernando , Lo Bianco Julio , Corbella Santomá Sergi 
Published: April 2003

AbstractWe posit the Personal Style of the Therapist (PST) construct. It is defined as ‘the set of characteristics that each therapist applies in every psychotherapeutic situation, thus shaping the main attributes of the therapeutic act’. Its background is examined and its main traits are described. It includes five bipolar dimensions: Instructional, Expressive, Engagement, Attentional and Operative. It may be assessed through a self‐descriptive inventory. We list the psychometric properties found when the instrument was applied to a sample of N = 189 therapists in Argentina. We calculated descriptive statistics of the sample (means and standard deviations) and reliability coefficients (test–retest and Cronbach's alpha). To examine the dimension of the data a factor analysis of the main components was carried out using Varimax rotation. Results and potential applications of the instrument are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Reversal of lipopolysaccharide‐induced thermal and behavioural hyperalgesia by quercetin
Authors: Anjaneyulu Muragundla , Chopra Kanwaljit 
Published: April 2003

AbstractLipopolysaccharide (LPS), a major constituent of the outer membrane of the cell wall of gram‐negative bacteria, is known to cause inflammatory pain. Quercetin, a dietary flavonoid, is claimed to have antiinflammatory activity in a few experimental studies. However, it is not known whether quercetin can reverse the hyperalgesia that is secondary to the inflammation. The aim of the present study was to evaluate the effect of quercetin on LPS‐induced alteration of pain perception in mice. Central perception of pain was assessed with the tail‐flick and hot plate methods and behavioural hyperalgesia was assessed by noting the animal's reactions such as redness, paw licking, and rearing after the intraplantar injection of LPS (10 μg/paw). Local administration of LPS induced significant hyperalgesia when measured by both central effects and behavioural reactions. Quercetin (50 and 100 mg/kg), like dexamethasone (0.5 mg/kg), attenuated central and behavioural hyperalgesia. This effect of quercetin was sensitive to reversal by naloxone (2 mg/kg). Our results thus indicate that quercetin protects against LPS‐induced hyperalgesia through modulation of the opioidergic system. Drug Dev. Res. 58:248–252, 2003. © 2003 Wiley‐Liss, Inc.
Discovery and investigation of lead compounds as binders to the Extra‐Domain B of the angiogenesis marker, fibronectin
Authors: Scheuermann Jörg , Volonterio Alessandro , Zerbe Oliver , Zanda Matteo , Neri Dario 
Published: April 2003

AbstractAngiogenesis, the growth of new blood vessels from preexisting vessels, is a rare event in the adult (except in the case of the female reproductive cycle), but is a characteristic feature of diseases such as cancer, blinding ocular disorders (e.g., retinopathies), and rheumatoid arthritis. The ED‐B domain of fibronectin, a domain of 91 amino acids, inserted by a mechanism of alternative splicing of the primary transcript into the fibronectin molecule, is a high‐quality marker of angiogenesis and a target for molecular intervention, characterized by a high number of acidic residues on its surface, as well as some solvent‐exposed hydrophobic residues. A library of 113 low molecular‐weight organic compounds, containing both an aromatic moiety and at least one positive charge, was screened for binding to the ED‐B domain, using two‐dimensional heteronuclear NMR spectroscopy. One lead compound, 2,2‐diphenylethylamine, was found that binds specifically to the ED‐B domain, albeit with a dissociation constant in the millimolar range. Chemical modification of this scaffold revealed structural determinants required for binding, as well as amino acid residues in the ED‐B domain responsible for the interaction. The results presented represent the basis for the development of high‐affinity, low molecular‐weight binders by using a linked‐fragment approach or elongating the scaffold by means of combinatorial chemistry. Drug Dev. Res. 58:268–282, 2003. © 2003 Wiley‐Liss, Inc.
Predicted heats of combustion of some important organosilicon intermediates
Authors: Hshieh Fu‐Yu , Hirsch David B. , Beeson Harold D. 
Published: April 2003

AbstractThis short communication presents the predicted heats of combustion of 308 organosilicon intermediates. The net and gross heats of combustion were predicted using two previously developed empirical equations. These intermediates cover most of the important organosilicon compounds that are manufactured or used in the silicone industry. Copyright © 2003 John Wiley & Sons, Ltd.
A model to predict fire resistance of non‐load bearing wood‐stud walls
Authors: Takeda H. 
Published: April 2003

AbstractThe author has developed a series of computer models to predict the fire resistance of wood‐framed walls and floors. The models utilize two‐dimensional heat‐conduction equations and thermo‐physical property data to describe heat transfer through the assemblies. The model for wall assemblies WALL2D, the basic version of the wall model, has already been published in Fire and Materials. Recently, WALL2D has been extended to WALL2DN to analyse heat transfer through insulated walls and walls that experience openings at the joints between adjacent sheets of gypsum board. Since gypsum board shrinks at high temperatures, the joints between adjacent sheets of gypsum board open. Hot fire gases, thereby, enter the openings and heat the edge of the gypsum board and wood studs. The new model WALL2DN simulates the joint opening and describes the resultant effect of openings. The model also calculates heat transfer through insulation in the stud cavity and depicts the effect of insulation on the fire resistance of non‐load bearing wall assemblies. Insulation selected in WALL2DN is glass‐fibre insulation, rock‐fibre insulation, polystyrene foam and polyurethane foam. When walls are exposed to fire, the insulation in the cavity shrinks (and/or melts) and an empty space appears at the interface between insulation and gypsum board. The model simulates this shrinking behaviour of insulation in the cavity. Finally, the model was validated by comparing the predicted results to those from full‐scale standard fire‐endurance tests. Copyright © 2003 John Wiley & Sons, Ltd.
Annular liquid jets at high Reynolds numbers
Authors: Georgiou G. 
Published: April 2003

AbstractThe flow of annular liquid jets at high Reynolds numbers is analysed by means of the finite element method and the full‐Newton iteration scheme. Results have been obtained for various values of the inner to the outer diameter ratio and for non‐zero surface tension, using extremely long meshes. The annular film moves far from the symmetry axis at low values of the Reynolds number. At higher Reynolds numbers, the film moves towards the axis of symmetry and appears close to very far downstream, forming a round jet. Asymptotic results for the radius of the resulting round jet are provided. Copyright © 2003 John Wiley & Sons, Ltd.
Finite‐element simulation of incompressible fluid flow in an elastic vessel
Authors: Chen Harry Y. H. , Sheu Tony W. H. 
Published: April 2003

AbstractFinite‐element simulation was performed to predict the incompressible Navier–Stokes flow in a domain, partly bounded by an elastic vessel, which is allowed to vary with time. Besides satisfying the physical conservation laws, both surface and the volume conservation laws are satisfied at the discrete level for ensuring the balance between physical and geometrical variables. Several problems which are amenable to analytical solutions were tested for validating the method. The simulated results are observed to agree favourably with analytical solutions. Having verified the applicability of the finite‐element code to problems involving moving grids, we consider an incompressible fluid flow bounded by rigid and elastic vessel walls. Our emphasis was placed on the validation of the formulation developed within the moving‐grid framework. Copyright © 2003 John Wiley & Sons, Ltd.
A new hybrid turbulence modelling strategy for industrial CFD
Authors: Basara B. , Jakirlic S. 
Published: April 2003

AbstractThis paper presents a new strategy for turbulence model employment with emphasis on the model's applicability for industrial computational fluid dynamics (CFD). In the hybrid modelling strategy proposed here, the Reynolds stress and mean rate of strain tensors are coupled via Boussinesq's formula as in the standard k–εmodel. However, the turbulent kinetic energy is calculated as the sum of the normal Reynolds‐stress components, representing the solutions of the appropriate transport equations. The equations governing the Reynolds‐stress tensor and dissipation rate have been solved in the framework of a ‘background’ second‐moment closure model. Furthermore, the structure parameter C‐µ has been re‐calculated from a newly proposed functional dependency $f(\overline{u_{i}u_{j}},\partial U_{i}/\partial x_{j})$ rather than kept constant. This new definition of C‐µ has been assessed by using direct numerical simulation (DNS) results of several generic flow configurations featuring different phenomena such as separation, reattachment and rotation. Comparisons show a large departure of C‐µ from the commonly used value of 0.09. The model proposed is computationally validated in a number of well‐proven fluid flow benchmarks, e.g. backward‐facing step, 180° turn‐around duct, rotating pipe, impinging jet and three‐dimensional (3D) Ahmed body. The obtained results confirm that the present hybrid model delivers a robust solution procedure while preserving most of the physical advantages of the Reynolds‐stress model over simple k–εmodels. A low Reynolds number version of the hybrid model is also proposed and discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Efficient discretization of pressure‐correction equations on non‐orthogonal grids
Authors: Lehnhäuser T. , Schäfer M. 
Published: April 2003

AbstractAn alternative discretization of pressure‐correction equations within pressure‐correction schemes for the solution of the incompressible Navier–Stokes equations is introduced, which improves the convergence and robustness properties of such schemes for non‐orthogonal grids. As against standard approaches, where the non‐orthogonal terms usually are just neglected, the approach allows for a simplification of the pressure‐correction equation to correspond to 5‐point or 7‐point computational molecules in two or three dimensions, respectively, but still incorporates the effects of non‐orthogonality. As a result a wide range (including rather high values) of underrelaxation factors can be used, resulting in an increased overall performance of the underlying pressure‐correction schemes. Within this context, a second issue of the paper is the investigation of the accuracy to which the pressure‐correction equation should be solved in each pressure‐correction iteration. The scheme is investigated for standard test cases and, in order to show its applicability to practical flow problems, for a more complex configuration of a micro heat exchanger. Copyright © 2003 John Wiley & Sons, Ltd.
The geochemical characteristics of the Paraná River suspended sediment load: an initial assessment
Authors: Depetris Pedro J. , Probst Jean‐Luc , Pasquini Andrea I. , Gaiero Diego M. 
Published: April 2003

AbstractMost water in the Paraná River drainage basin is supplied by the tropical Upper Paraná (over 60% of the total annual water discharge, 550 km3). The total suspended solids (TSS) load (c. 80 × 106 t year−1), however, is essentially furnished (50–70%) by the mountainous, arid and mostly sediment‐mantled upper Bermejo River drainage basin. This characteristic suggests that the Paraná River solid load (TSS, 600 km upstream from the mouth) is largely recycled sedimentary material, whose discharge‐weighted mean chemical index of alteration is c. 71. The extended UCC‐normalized multi‐elemental diagrams are similar to those of other world rivers. Nevertheless, the detailed inspection of UCC‐normalized rare earth element (REE) ‘spidergrams’ reveals a lithological source for the Paraná River TSS that might be compatible with either tholeiitic flood basalts (widespread in the upper drainage) or with young Andean intermediate volcanic rocks. In view of the Bermejo River's dominant role as a sediment contributor, we feel that the signature preserved in the Paraná's TSS is the latter. Conversely, the Uruguay River TSS REE signature is certainly determined by the extensive weathering products of Jurassic–Cretaceous tholeiitic basalts. Copyright © 2003 John Wiley & Sons, Ltd.
Physicochemical variables and plankton from the Lower Delta of the Paraná River (Argentina) in relation to flow
Authors: de Cabo Laura , Puig Alba , Arreghini Silvana , Olguín Héctor F. , Seoane Rafael , Obertello Irene 
Published: April 2003

AbstractThis study evaluates temporal variations of physicochemical variables and densities of phytoplankton and zooplankton, under different flow conditions. Four samplings were carried out at four sites on the Lower Delta of the Paraná River (Argentina). This first approach was developed in 1995 and included a flood of high amplitude and average duration. Daily data analysis along the year qualified sampling water levels as very high, medium (two opportunities) and low level. Triplicate subsuperficial water samples were taken in the middle of the navigation channel. Dissolved oxygen, pH, conductivity and temperature were determined in situ; nutrients and concentration of major solutes in the laboratory. Quantitative samples of phytoplankton (concentrated by sedimentation) and zooplankton (80 l; 48 µm) were obtained. Temporal variation of most physical, chemical and biological variables exceeded the spatial variation. Physicochemical variables were mainly associated in time with the hydrological regime. In the main channel water exchange originated by the flood of marshy environments caused dissolved oxygen, nitrate and sulphate to decrease and phosphate, conductivity, bicarbonate, calcium and magnesium to increase. The dilution–concentration action of flow was evidenced in chloride variation (conservative ion). The plankton variables would be affected directly and indirectly by water level, and also by seasonal climatic condition. The densities of phytoplankton and zooplankton increased during low flow. For some organisms, the variation in density exceeded the simple concentration effect of flow decrease. The lowest plankton densities coincided with a temperature minimum. Copyright © 2003 John Wiley & Sons, Ltd.
Modelling point and diffuse heavy metal emissions and loads in the Elbe basin
Authors: Vink Rona , Peters Steef 
Published: April 2003

AbstractThe reduction of pollutant loads in rivers requires a good comprehension of the contribution of all major (point and diffuse) sources in each sub‐basin. Due to the sudden change of a centrally planned economy to a free‐market economy in 1989, the River Elbe is one of the fastest changing transboundary river basins in Central Europe. The quantification of fluxes of heavy metals in the Elbe basin requires information on the spatial and temporal characteristics of emissions and on physical boundary conditions of the entire river basin. In this paper, a GIS‐based model METALPOL will be presented, that describes the load of five heavy metals (Cd, Cu, Hg, Pb, Zn) in the Elbe basin over the period 1985–1999 as a function of (1) emissions from point and diffuse sources, (2) runoff, (3) soil types, (4) land use and (5) hydrogeology. The results from the model were validated with the measured heavy metal loads and showed reasonable agreement. Between 64% (for Hg) and 84% (for Pb) of the total heavy metal emissions in the Elbe basin is supplied by inputs from diffuse sources. The diffuse hydrological pathways with the highest share are erosion and urban areas. In most cases the measured heavy metal load is lower than the sum of the heavy metal emissions. Retention processes (e.g. sedimentation) largely explain this behaviour and are found to be dependent on the specific runoff of a catchment. About 81–97% of variance for the different heavy metals can be explained by the dependency on specific runoff. The uncertainty analysis presented in this paper has also illustrated that the reliability of the model simulations is directly affected by the quality of the input data (especially point source and urban emissions) and the distribution of the input data like rainfall data, emission data, soil data and land cover data. Finally, scenario analysis indicated that the current proposed measures are not stringent enough to achieve large reductions in heavy metal loads in the Elbe basin. Copyright © 2003 John Wiley & Sons, Ltd.