bluuebunny/crossref_metadata_2025_split huggingface dataset:
Small‐angle X‐ray scattering analysis of nanophase titanium dioxide, poly[N‐(4‐sulfophenyl)aniline], and their composite
Authors: Narsimlu Nachagoni , Kuo Yen‐Ding , Wu Chun‐Guey 
Published: April 2003

AbstractSmall‐angle X‐ray scattering and spectroscopic (infrared and ultraviolet–visible) techniques were used to investigate the interactions between titanium dioxide (TiO2) and the semiconductor polymer poly[N‐(4‐sulfophenyl)aniline] (PSA) in a poly[N‐(4‐sulfophenyl)aniline]/TiO2 composite (TPSA). The radius of gyration of the cross section, the radius and length of the rodlike particle, the persistence length, the surface fractal dimension, and the PSA layer thickness on TiO2 in aqueous solutions and in powder form were calculated. The results indicated that the aggregation of TiO2 particles on drying was reduced by the formation of the composite with the semiconductor polymer. Only the particle length of the TPSA particle (which had a rodlike shape) increased on drying, probably because of increasing void sizes and the formation of aggregation. The persistence length of the TPSA particles decreased with respect to its individual components. The PSA layer thickness on TiO2 was about 3.6 nm and decreased (to 2.6 nm) on dehydration because of the expulsions of water molecules from the TiO2/PSA composite. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3183–3187, 2003
Preparation of chlorinated poly(vinyl chloride)‐g‐poly(N‐vinyl‐2‐pyrrolidinone) membranes and their water permeation properties
Authors: Seok Kang Jong , Hoon Lee Sang , Huh Hoon , Kie Shim Jin , Moo Lee Young 
Published: April 2003

AbstractChlorinated poly(vinyl chloride) (CPVC) membranes for microfiltration processes were prepared with the combined process of a solvent evaporation technique and the water‐vapor induced‐phase‐inversion method. CPVC membranes with a mean pore size of 0.7 μm were very hydrophobic. These membranes were subjected to surface modification by ultraviolet (UV)‐assisted graft polymerization with N‐vinyl‐2‐pyrrolidinone (NVP) to increase their surface wettability and decrease their adsorptive fouling. The grafting yields of the modified membranes were controlled by alteration of UV irradiation time and NVP monomer concentration. The changes in chemical structure between the CPVC membrane and the CPVC‐g‐poly(N‐vinyl‐2‐pyrrolidinone) membrane and the variation of the topologies of the modified PVC membranes were characterized by Fourier transform infrared spectroscopy, gel permeation chromatography, and field emission scanning electron microscopy. According to the results, the graft yield of the modified CPVC membrane reached a maximum at 5 min of UV exposure time and 20 vol % NVP concentration. The filtration behavior of these membranes was investigated with deionized water by a crossflow filtration measurement. The surface hydrophilicity and roughness were easily changed by the grafting of NVP on the surface of the CPVC membrane through a simultaneous irradiation grafting method by UV irradiation. To confirm the effect of grafting for filtration, we compared the unmodified and modified CPVC membranes with respect to their deionized water permeation by using crossflow filtration methods. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3188–3195, 2003
Vinyl polymerization of norbornene with dinuclear diimine nickel dichloride/MAO
Authors: Mi Xia , Ma Zhi , Cui Nannan , Wang Leyong , Ke Yucai , Hu Youliang 
Published: April 2003

AbstractVinyl‐addition polymerization of norbornene was accomplished by two novel dinuclear diimine nickel dichloride complexes in combination with methylaluminoxane (MAO). The activities were moderate. The catalyst structure, Al/Ni molar ratio, solvents, and polymerization temperature all affected the catalytic activities. The obtained polynorbornenes were characterized by 1H‐NMR, 13C‐NMR, FTIR, DSC, WAXD, and intrinsic viscosity measurements. The vinyl‐addition polymers were amorphous but with a short‐range order and high packing density. The polynorbornenes showed glass transition temperatures (Tg) above 240°C and decomposed above 400°C. The catalyst structure and polymerization conditions have effects on the molecular weight and the microstructure of the polymers. The nickel complex with bulkier substituents in the ligand produced polynorbornene with a higher packing density and higher regularity and, therefore, with higher Tg. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3273–3278, 2003
Fracture properties of nanoclay‐filled polypropylene
Authors: Chen Ling , Wong Shing‐Chung , Pisharath Sreekumar 
Published: April 2003

AbstractMaleic anhydride‐modified polypropylene was compounded with commercially available surface‐modified montmorillonite in a twin‐screw extruder. Recompounding ensured the removal of visible tactoids from the extrudate but TEM and XRD techniques showed nonuniform dispersion of clay platelets. In this study, we investigated the mechanical and fracture properties of nanoclay‐filled polypropylene. Emphasis was placed on the fracture characterization of the clay‐filled polypropylene. Tensile strength and stiffness increased steadily with an increase in the clay loading. The toughness of compounded materials was characterized using rigorous fracture mechanics. J‐integral fracture resistance decreased with an increase in the clay content. The resistance against stable crack growth was compared using the slopes derived from the J–R curve and the tearing modulus concept. A significant amount of crack growth resistance was evident in the nanoclay‐filled polypropylene as opposed to other brittle nanocomposites such as the nylon–clay systems. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3298–3305, 2003
Ultrasonic and viscometric investigations of a poly(vinyl alcohol)–dextran mixture in aqueous solution
Authors: Sahoo Prafulla K. , Mohapatra Roomky , Sahoo Anusmita , Swain Sarat K. 
Published: April 2003

AbstractUltrasonic spectroscopy provided a powerful, efficient, and reliable tool for a number of investigations, including those of polymer solution dynamics, molecular interaction, and the miscibility and compatibility of biopolymers in aqueous solutions. Ultrasonic velocity and related acoustic parameters were measured as a function of the concentration of poly(vinyl alcohol) (PVA), dextran, and a PVA–dextran mixture in water with the resonance method at a frequency of 3 MHz over a temperature range of 20–50°C. From the comparative results of sound velocity, density, adiabatic compressibility, acoustic impedance, and viscosity relaxation time as a function of temperature and concentration, the mode of interaction and the compatibility and miscibility between the two biologically active macromolecules were probed and were considerable at all concentrations and temperatures because of crosslinking via hydrogen bonding involving the hydroxyl groups of both of the biomacromolecules. The interpretations of the acoustic results were confirmed by the intrinsic viscosities of the ternary systems. The significant interaction and compatibility of these biopolymers should lead to the development of pharmaceutically active molecules. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3196–3201, 2003
Effects of lignin as a filler on properties of soy protein plastics. II. Alkaline lignin
Authors: Huang Jin , Zhang Lina , Chen Pu 
Published: April 2003

AbstractBlend plastics based on soy protein isolate (SPI) strengthened with alkaline lignin (AL) in the weight ratio of 10:0 to 5:5 were prepared with 40 wt % glycerol as a plasticizer by compression molding. The structure and mechanical properties of the blends were investigated by wide‐angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamical mechanical thermal analysis (DMTA), and tensile tests. The results indicated that the introduction of AL could effectively increase the tensile strength and Young's modulus, thermal stability, and elongation of the compositive plastics when the AL content ranged from 10 to 20 parts. Moreover, the blend plastics containing 50 parts AL exhibited maximum tensile strength (1.98 MPa) and much higher than that with the SP–AL0 sheet with AL alone (0.89 MPa). In addition, tests of water absorption proved that the introduction of hydrophobic AL effectively reduced water absorption and, hence, decreased water sensibility. Therefore, AL, a relatively low‐cost filler, plays a major role in enhancing the strength and water resistivity of soy protein plastics. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3291–3297, 2003
Moderated validity of clinical informant assessment: use in depression and personality
Authors: Kamphuis J. H. , Emmelkamp P. M. G. , de Vries V. 
Published: April 2003

AbstractInformant assessment or indirect assessment is often a valuable adjunct in clinical practice. Validity of informant assessment has typically been measured as the degree of agreement with self‐report, and has generally been encouraging in both non‐clinical and clinical samples. The present article describes two small‐scale validity studies in an inpatient psychiatric setting and in the community at large, respectively. The first study in a depressed inpatient sample reports on self‐ and informant‐ratings of depressive symptoms, and also examines the moderating influence of informant levels of depression. Results of this study indicate that partners are able to make fairly accurate estimates of the depressed patient's clinical status in terms of depressive symptoms. The second study reports on female participants' personality descriptions of their male partner, and examines to what extent marital distress moderates the agreement. Overall agreement between self‐ and spouse‐ratings of personality traits was satisfactory to high, and the degree of marital distress was not a factor in the accuracy of judgment. Generally, agreement indices were solid and close to test–retest values. Clinical utility and directions for future applications of informant assessment are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
A self‐directed psychosocial intervention with minimal therapist contact for adults with attention deficit hyperactivity disorder
Authors: Stevenson Caroline S. , Stevenson Richard J. , Whitmont Stephanie 
Published: April 2003

AbstractUsing a randomized controlled design, the efficacy of a self‐directed psychosocial intervention with minimal therapist contact, aimed at reducing the symptoms of adult ADHD, was examined. Following the intervention, the treatment group reported significantly reduced ADHD symptomatology; improved organizational skills; improved self esteem and better anger control, when compared to waiting list controls. Comorbid anxiety, depression, high levels of stress and learning problems, did not effect treatment outcome. Improvements in ADHD symptomatology and organizational skills were maintained at a 2‐month follow‐up. Although the programme was successful, close adherence to the programme was necessary for optimum treatment gains. These findings build upon an earlier study that used a more intensive form of programme delivery and support the view that psychosocial interventions can enhance daily functioning for adult ADHD. Copyright © 2003 John Wiley & Sons, Ltd.
Reduction of incongruence in inpatient psychotherapy
Authors: Berking M. , Grosse Holtforth M. , Jacobi C. 
Published: April 2003

AbstractAccording to consistency theory, incongruence between individual perceptions and goals reduces well‐being and increases the risk for the development and further maintenance of psychopathological disorders. Successful psychotherapy should therefore reduce the level of incongruence and therapy outcome should be associated with the reduction of incongruence. To test these hypotheses the level of incongruence was assessed in a sample of 62 inpatients undergoing cognitive‐behavioural therapy (CBT) before and after treatment using the Incongruence Questionnaire. Pre–post differences were then correlated with other outcome measures and factor analysis was used to assess the underlying dimensionality of all outcome measures. The level of congruence was reduced substantially by inpatient CBT, changes were positively related to other measures of psychotherapy outcome and incongruence loaded strongly on only one of two emerging factors. Incongruence can be seen as an independent construct. It seems advisable to assess level of incongruence at the beginning of each psychotherapy for effective planning of treatment and at the end of therapy for a comprehensive outcome measurement. The reduction of high levels of incongruence must be seen as an important higher level goal in psychotherapy. Further research has to clarify under what conditions the reduction of incongruence is especially important and what methods are most effective to do so. Copyright © 2003 John Wiley & Sons, Ltd.
Differences in coupling interval‐dependent effects of sotalol on infarcted and noninfarcted areas of dog hearts after myocardial infarction
Authors: Hashimoto Hisakuni , Ohmura Tomohiro , Nakamura Ryuta , Ikeda Yasuhiko , Umemura Kazuo 
Published: April 2003

AbstractWe examined the coupling interval‐dependence of the effects of sotalol (dl‐sotalol) on effective refractory periods (ERPs) and epicardial activation in ventricles of dog hearts after myocardial infarction, and clarified their differences between infarcted and noninfarcted areas. Myocardial infarction was produced by the two‐stage ligation of left anterior descending coronary artery in dogs. At 7 to 9 days after ligation, bipolar electrodes were sutured on the ventricular surface of the noninfarcted and the infarcted areas. Single (S1) or double (S1/S2) electrical stimulations with various coupling intervals were applied on the ventricle during atrial pacing. S1 was triggered by a prior R wave of pacing rhythm with coupling interval of 300 ms (S1[300]) or 180 ms (S1[180]). Coupling intervals of S1 and S2 were between 250 and 130 ms. ERPs, activation delay, and functional refractory periods (FREPs) in ventricles were measured after S1(180) or S1(300). Ventricular activation delay was a time interval from the artifact of S1 or S2 to the most delayed measurable wave. The coupling interval of S1–S2 was 170 or 160 ms. RT intervals were measured in the bipolar ECGs after S1(300) or S1(180). Sotalol was administered intravenously in dosages of 2, 4, and 8 mg/kg. Sotalol prolonged the ERPs in noninfarcted areas in a lesser extent after S1(180) than after S1(300), whereas in infarcted areas the ERP prolongation was in a similar extent after S1(180) and S1(300). Sotalol prolonged the RT intervals in a lesser extent after S1(180) than after S1(300) in noninfarcted areas, but in a similar extent after S1(180) and after S1(300) in infarcted areas. FERPs were also prolonged by sotalol in infarcted areas in a similar extent after S1(180) and after S1(300). Sotalol prolonged ventricular activation delay after S1/S2 in the infarcted areas, which was greater after S1/S2(180/170) than after (300/170). Delayed activation was blocked more frequently after the S1/S2(180/160) than after S1/S2(300/160). These results indicate that the effects of sotalol on ventricular activation delay are reverse‐use dependent in noninfarcted areas but use‐dependent in infarcted areas, which may contribute to suppression of ventricular tachyarrhythmias in patients with coronary heart disease. Drug Dev. Res. 58:258–267, 2003. © 2003 Wiley‐Liss, Inc.
In vivo efficacy of a novel double liposome as an oral dosage form of salmon calcitonin
Authors: Ebato Yoshinori , Kato Yoshinori , Onishi Hiraku , Nagai Tsuneji , Machida Yoshiharu 
Published: April 2003

AbstractA simple method for the preparation of the inner liposomes for double liposomes (DL) was developed. The encapsulation efficiency of erythrosine in liposomes prepared by this new method is superior to that of the previous method because of the concentration of the drug in the lipid membrane. To evaluate the usefulness of DL prepared by the glass‐filter method modified in this study as an oral dosage form of salmon calcitonin (SCT), a suspension of liposomes containing SCT was administered to rats at a dose of 10 μg SCT/kg. Each type of DL showed better efficacy than its inner liposomes alone. The decrease in plasma calcium level was dependent on the electrical charge and particle size of the inner liposomes. The hypocalcemic efficacy of DL encapsulating SCT‐loading cationic liposomes relative to that after subcutaneous administration of SCT at a dose of 1 μg/kg was 6.47%, which was the largest value obtained. These results indicated that not only the particle size but also the electrical charge of inner liposomes affect intestinal absorption. This study verified that the efficacy was increased because of the decrease in diameter of the inner liposomes and the use of lipid with a positive charge. These findings concluded that DL might be useful as an oral dosage form of SCT. Drug Dev. Res. 58:253–257, 2003. © 2003 Wiley‐Liss, Inc.
Influence of vehicles on the in vitro percutaneous absorption of piroxicam to optimise the formulation of patch tests in dermatology
Authors: d'Arpino Stéphanie , Corbrion‐Archer Valérie , Marty Jean‐Paul , Lantieri Laurent , Vincent Claire‐Marie , Astier Alain , Paul Muriel 
Published: April 2003

AbstractThe present study evaluated the influence of various vehicles on the in vitro percutaneous absorption of piroxicam across human skin under standard diffusion conditions to optimise the formulation of patch tests in dermatology. The transdermal permeation properties of piroxicam were evaluated from five vehicles (PEG 400, propylene glycol, transcutol P, petrolatum, and petrolatum + transcutol P 10%) using Franz diffusion cells. Piroxicam was applied as a saturated solution in vehicles to ensure equal thermodynamic activity of piroxicam in the vehicles. Concentrations of piroxicam were determined by high performance liquid chromatography in epidermis, dermis, and receptor liquid. The release of piroxicam from its vehicles and consequently its cutaneous absorption are influenced by the vehicle assayed and the solubility of piroxicam in each vehicle. The penetration of piroxicam through human skin was clearly enhanced by propylene glycol and petrolatum + transcutol P 10%, with cumulated amounts of piroxicam in the receptor fluid at 48 h of 116±32 and 159±28 μg/mg/cm2 respectively, whereas petrolatum alone did not allow the diffusion of piroxicam. Additional experiments should be conducted in vivo to correlate the results obtained in vitro and to provide clinicians with a more reliable diagnostic test. Drug Dev. Res. 58:283–290, 2003. © 2003 Wiley‐Liss, Inc.
Some comments on the modes of action of nanocomposites in the flame retardancy of polymers
Authors: Lewin Menachem 
Published: April 2003

AbstractNanocomposites of polymers with montmorillonite (MMT) yield upon pyrolysis and combustion an MMT‐rich surface of the char. The prevalent approach considers this accumulation as due to the gasification of the polymer and subsequent gradual precipitation of the MMT on the surface. According to the present paper, the enrichment in MMT is postulated to be due to a migration or convection of the MMT to the surface driven mainly by the lower surface free energy of the MMT. The role of the surface free energy in the surface structure of polymer blends, especially those involving a silicon‐containing component, is discussed. The enrichment occurs above the glass transition temperature and is temperature dependent. XPS evidence for the accumulation of MMT on the surface of a polystyrene/MMT nanocomposite is reviewed. Its dependence on the stability of the nanocomposite structure, and particularly on the stability of the quaternary ammonium compounds that bind the polymer to the MMT, is pointed out. The importance of the surface free energy in the flame retardancy of polymer blends as well as polymer‐additive mixtures is discussed. Copyright © 2003 John Wiley & Sons, Ltd.
A flux‐splitting solver for shallow water equations with source terms
Authors: Rebollo Tomás Chacón , Nieto Enrique D. Fernández , Mármol Macarena Gómez 
Published: April 2003

AbstractThis paper introduces a stable flux‐splitting solver for one‐dimensional (1D) shallow water equations. This solver is specifically designed to satisfy a strengthened consistency condition for stationary solutions that ensures the stability and accuracy of the scheme. It applies to channels with variable depth and width, including terms modelling friction at bottom and vertical walls. Some numerical tests by comparison to both analytical solutions and experimental measurements show the good performances of the scheme. Copyright © 2003 John Wiley & Sons, Ltd.
A novel fully implicit finite volume method applied to the lid‐driven cavity problem—Part I: High Reynolds number flow calculations
Authors: Sahin Mehmet , Owens Robert G. 
Published: April 2003

AbstractA novel implicit cell‐vertex finite volume method is described for the solution of the Navier–Stokes equations at high Reynolds numbers. The key idea is the elimination of the pressure term from the momentum equation by multiplying the momentum equation with the unit normal vector to a control volume boundary and integrating thereafter around this boundary. The resulting equations are expressed solely in terms of the velocity components. Thus any difficulties with pressure or vorticity boundary conditions are circumvented and the number of primary variables that need to be determined equals the number of space dimensions. The method is applied to both the steady and unsteady two‐dimensional lid‐driven cavity problem at Reynolds numbers up to 10000. Results are compared with those in the literature and show excellent agreement. Copyright © 2003 John Wiley & Sons, Ltd.
Calculation of turbulent fluid flow and heat transfer in ducts by a full Reynolds stress model
Authors: Rokni Masoud , Sundén Bengt 
Published: April 2003

AbstractA computational method has been developed to predict the turbulent Reynolds stresses and turbulent heat fluxes in ducts by different turbulence models. The turbulent Reynolds stresses and other turbulent flow quantities are predicted with a full Reynolds stress model (RSM). The turbulent heat fluxes are modelled by a SED concept, the GGDH and the WET methods. Two wall functions are used, one for the velocity field and one for the temperature field. All the models are implemented for an arbitrary three‐dimensional channel.Fully developed condition is achieved by imposing cyclic boundary conditions in the main flow direction. The numerical approach is based on the finite volume technique with a non‐staggered grid arrangement. The pressure–velocity coupling is handled by using the SIMPLEC‐algorithm. The convective terms are treated by the van Leer scheme while the diffusive terms are handled by the central‐difference scheme. The hybrid scheme is used for solving the ε equation.The secondary flow generation using the RSM model is compared with a non‐linear k–ε model (non‐linear eddy viscosity model). The overall comparison between the models is presented in terms of the friction factor and Nusselt number. Copyright © 2003 John Wiley & Sons, Ltd.