bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on polyamide‐6/polyolefin blend system compatibilized with epoxidized natural rubber
Authors: Xie Bang‐hu , Yang Ming‐bo , Li Si‐dong , Li Zhong‐ming , Feng Jian‐min 
Published: February 2003

AbstractInfrared spectra of polyamide‐6 (PA6) with and without epoxidized natural rubber (ENR) are presented. The influence of ENR used as a compatibilizer on the morphologies, crystallizability, mechanical properties, and thermal behavior of the polyamide‐6/polyolefins (PO) blends are studied. The infrared spectra suggest that under normal processing conditions, the carboxyl end groups of PA6 could chemically react in situ with the epoxy groups of ENR, and ester groups are created. This means that the PA6‐ENR grafting copolymer could be obtained during processing. All the morphological characterizations and thermal analyses show that the compatibility of PA6/PO blends is obviously improved by ENR because the copolymer increases the interaction between PA6 and PO. It is also found that the toughness of PA6/PO blends increase significantly after using ENR, while the tensile strength and the softening temperature of PA6/PO blends have almost no change. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 398–403, 2003
Novel cellulose ester–poly(furfuryl alcohol)–flax fiber biocomposites
Authors: Toriz G. , Arvidsson R. , Westin M. , Gatenholm P. 
Published: February 2003

AbstractComposites based entirely on renewable materials with flax fibers as reinforcement and cellulose acetate butyrate (CAB) as the matrix were prepared by compression molding. Scanning electron microscopy of the fracture surfaces showed insufficient penetration of the matrix into the fiber mat. Rheological measurements indicated that this was caused by the high melt viscosity of CAB. Various amounts of furfuryl alcohol (FA) were added to the matrix to control the melt viscosity of CAB. The melt viscosity was decreased dramatically by the introduction of FA, which acted as a CAB solvent and facilitated the impregnation of the flax fiber mats. The mechanical and dynamic thermal properties of composites based on flax mats and various amounts of CAB and FA were investigated. The addition of FA to CAB and the polymerization of FA resulted in a linearly increased modulus and an increase in the maximum fiber stress (strength) of flax composites but a decreased toughness. Dynamic mechanical thermal analysis (DMTA) showed that CAB/poly(furfuryl alcohol) (PFA) matrices were miscible because the glass‐transition temperature (Tg) in the resulting blends occurred between the Tg of the homopolymers. DMTA also showed that increasing the amount of FA in the matrix substantially increased the storage modulus of the composites at temperatures lower than 80°C. It was possible to tune the storage properties of the composites through the addition of appropriate amounts of FA to the matrices. The CAB/PFA matrix showed behavior between that of thermoplastics and thermosets because of the miscibility and affinity of its components. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 337–345, 2003
Spectroscopic behavior of poly(vinyl alcohol) films with different molecular weights after UV irradiation, thermal annealing, and double treatment with UV irradiation and thermal annealing
Authors: Abd El‐Kader Kamal M. 
Published: February 2003

AbstractPure poly(vinyl alcohol) (PVA) films with molecular weights 5,000, 72,000, and 125,000 g/mole were prepared by casting technique. The thickness of prepared samples was 0.21 mm. Xenon arc lamp was used to irradiate two samples from each molecular weight at 400 W for 5 min. One from each irradiated PVA samples was heated at 423 K for 2 h. An additional PVA sample unirradiated from each molecular weight was heated at 423 K for 2 h. Optical absorption measurements have been carried out in the wavelength range of 190–900 nm for untreated, UV‐irradiated, heated, and double‐treated samples by UV irradiation and heat. The double‐treated PVA samples with molecular weights 5,000 and 72,000 g/mole showed approximately zero transmission in comparison with untreated PVA sample in the wavelength range of 190–320 nm. PVA sample with 125,000 g/mole was irradiated with 600 W for 5 min to obtain the zero transmission in the same wavelength range. Identification of the structure and assignments of energy bands were studied also by using FTIR. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 589–594, 2003
Effect of film draw temperature (FDT) on physical properties of polyethylene
Authors: Basfar A. A. , Idriss Ali K. M. 
Published: February 2003

AbstractThin polymer films (0.06 mm thick) were prepared with LLDPE (coded as A) and LDPE (coded as D) at different film draw temperatures (FDTs) from 5 to 65°C. There was about a 42% enhancement of the tensile strength when the LLDPE film was drawn at 45°C and LDPE at 35°C and the ultimate elongation increased between 14 and 32%. When various additives were incorporated into these resins A and D, the tensile strength slightly decreased, but the ultimate elongation increased. Films which attained the highest tensile properties showed the maximum resistance against degradation by natural outdoor weathering. Although irradiation of these films by a gamma source caused reduction of their tensile properties, there was a general tendency of resisting this reduction with increase of the FDT. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 459–465, 2003
Effect of concentration and pH of solutions on the absorbency of polyacrylate superabsorbents
Authors: Kang Hongmei , Xie Jianjun 
Published: February 2003

AbstractPolyacrylate superabsorbent (PAS) was synthesized by aqueous solution polymerization crosslinked by N,N‐methylene bisacrylamide. The effect of pH and concentration of several solutions on absorbency (Q) of PAS was studied. The results showed that the absorbency increased at first and then decreased with the increase of the solution's pH; the summit of the absorbing curve was attained when pH was about 6.25. The relation between absorbency and pH could be represented by a quadratic equation and the square difference was relatively small. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 494–499, 2003
Measurement and numerical simulation of three‐dimensional fiber orientation states in injection‐molded short‐fiber‐reinforced plastics
Authors: Lee Kwang Seok , Lee Seok Won , Chung Kwansoo , Kang Tae Jin , Youn Jae Ryoun 
Published: February 2003

AbstractTo determine three‐dimensional fiber orientation states in injection‐molded short‐fiber composites, a confocal laser scanning microscope (CLSM) is used. Since the CLSM optically sections the specimen, more than two images of the cross sections on and below the surface of the composite can be obtained. Three‐dimensional fiber orientation states can be determined by using geometric parameters of fiber images obtained from two parallel cross sections. For experiments, carbon‐fiber‐reinforced polystyrene is examined by the CLSM and geometric parameters of fibers on each cross‐sectional plane are measured by an image analysis. In order to describe fiber orientation states compactly, orientation tensors are determined at different positions of the prepared specimen. Three‐dimensional orientation states are obtained without any difficulty by determining the out‐of‐plane angles utilizing fiber images on two parallel planes acquired by the CLSM. Orientation states are different at different positions and show the shell–core structure along the thickness of the specimen. Fiber orientation tensors are predicted by a numerical analysis and the numerically predicted orientation states show good agreement with measured ones. However, some differences are found at the end of cavity. They may result from the fountain flow effects, which are not considered in the numerical analysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 500–509, 2003
Heterogeneous nucleation of nylon 6 and PET with selected inorganic compounds
Authors: Martínez‐Vázquez D. G. , Medellín‐Rodríguez F. J. , Phillips P. J. , Sanchez‐Valdes S. 
Published: February 2003

AbstractThe effect of several inorganic compounds in the heterogeneous nucleation of poly(ethylene terephthalate) (PET) and poly(caprolactam) (nylon 6) was studied. Six inorganic chemicals were specifically selected, on the basis of their crystal structure, basal lattice dimensions, and thermal properties, in order to study the effect of temperature in their nucleation capabilities. Considering that temperature is one of the most important variables involved during processing of thermoplastics, the impact of the nucleation ability of the intentionally added heterogeneities was studied in terms of thermal conductivity, thermal expansion, and heat capacity. Six inorganic chemicals, which crystallize in the cubic system, were selected considering that they had variations in one of the thermal properties while the others remained practically constant along the temperature range of interest. The results indicated that, at constant surface area, chemical compounds with lower overall values of thermal expansion and also those with overall higher values of heat capacity promote heterogeneous nucleation; the effect of heat capacity was, however, also found potentially related to a different intrinsic mechanism. The impact of thermal conductivity was not considered significant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 360–368, 2003
Development of a new instrument for rheumatoid arthritis: The Cedars‐Sinai Health‐Related Quality of Life instrument (CSHQ‐RA)
Authors: Weisman Michael H. , Paulus Harold D. , Russak Simcha M. , Lubeck Deborah P. , Chiou Chiun‐Fang , Sengupta Nishan , Ofman Joshua J. , Borenstein Jeff , Moadel Alyson B. , Sherbourne Cathy D. 
Published: February 2003

AbstractObjectiveTo update and complement existing instruments, we developed a multidimensional disease‐specific instrument, intended to reflect the impact of rheumatoid arthritis (RA) with modern treatment options on patient's Health‐Related Quality of Life (HRQOL).MethodsItems were developed from a systematic review of published HRQOL measures and transcripts of RA patient focus groups. Items were refined by an expert panel and administered to 350 patients for psychometric testing.ResultsThe systematic review identified 228 potential items, and the focus group transcripts identified 96 additional items. Expert review and pilot testing resulted in an initial 58‐item instrument. Twenty‐six items were excluded due to floor/ceiling effects, poor response rates, or high item‐item correlations. Factor analysis identified a 5‐factor structure (eigenvalues ≥1). Multi‐trait scaling performed on both completed surveys confirmed the 5 sub‐scale structure (Cronbach's > 0.87).ConclusionThe CSHQ‐RA consists of 33 items that address 5 HRQOL domains, each with high internal consistency. Additional testing will assess the instrument's validity and responsiveness.
Disease activity score for children with juvenile dermatomyositis: Reliability and validity evidence
Authors: Bode Rita K. , Klein‐Gitelman Marisa S. , Miller Michael L. , Lechman Toula S. , Pachman Lauren M. 
Published: February 2003

AbstractObjectiveTo assess the reliability and validity of the Disease Activity Score (DAS), an instrument used to evaluate children with juvenile dermatomyositis (JDM).MethodsPsychometric study of internal consistency, reliability, rater agreement, and the relationship with measures of muscle strength and disability was conducted.ResultsThe DAS ratings are internally consistent (reliability = 0.89) and describe a wide range of disease activity. The pediatric rheumatologists in this study agree on the presence of most of the disease indicators. Their disagreements tend to cancel each other, resulting in highly correlated (r = 0.79) overall measures across raters. Estimates of muscle weakness using the DAS and ratings of muscle strength obtained independently from therapists are highly related (r = −0.77), but estimates of disease activity and disability are weakly related (r = 0.20).ConclusionThe DAS exhibits evidence of good reliability and validity. The combination of skin and muscle strength assessments makes this easily administered instrument a useful addition in the evaluation of children with JDM.
Computing the transition state populations in simple protein models
Authors: Ozkan S. Banu , Dill Ken A. , Bahar Ivet 
Published: February 2003

AbstractWe describe the master equation method for computing the kinetics of protein folding. We illustrate the method using a simple Go model. Presently most models of two‐state fast‐folding protein folding kinetics invoke the classical idea of a transition state to explain why there is a single exponential decay in time. However, if proteins fold via funnel‐shaped energy landscapes, as predicted by many theoretical studies, then it raises the question of what is the transition state. Is it a specific structure, or a small ensemble of structures, as is expected from classical transition state theory? Or is it more like the denatured states of proteins, a very broad ensemble? The answer that is usually obtained depends on the assumptions made about the transition state. The present method is a rigorous way to find transition states, without assumptions or approximations, even for very nonclassical shapes of energy landscapes. We illustrate the method here, showing how the transition states in two‐state protein folding can be very broad ensembles. © 2002 Wiley Periodicals, Inc. Biopolymers 68: 35–46, 2003
Penile neuronal nitric oxide synthase and its regulatory proteins are present in hypothalamic and spinal cord regions involved in the control of penile erection
Authors: Ferrini Monica G. , Magee Thomas R. , Vernet Dolores , Rajfer Jacob , González‐Cadavid Nestor F. 
Published: February 2003

AbstractControl of penile erection requires the coordination of the hypothalamus and the L6–S1 region of the spinal cord. Erection requires the activation of neuronal nitric oxide synthase (nNOS), which is tightly regulated. Because variants of nNOS (penile nNOS: PnNOS) and the N‐methyl‐D‐aspartate receptor (truncated NMDAR subunit 1: NMDAR1‐T) as well as protein inhibitor of NOS (PIN) have all been located in the pelvic ganglia and penile nerves, this work aims to determine whether these proteins are also present in the hypothalamus. It was found that PnNOS, the brain‐type nNOS, and PIN, were expressed in the hypothalamus. In contrast, NMDAR1‐T was expressed only in the penis, whereas the brain‐type NMDAR1 was present in the brain and sacral spinal cord and not in the penis. PnNOS was found in the media preoptic area, posterior magnocellular, and the parvocellular regions of the paraventricular nucleus, supraoptic nucleus, septohypothalamic nucleus, medial septum, cortex, and in some of the nNOS staining neurons throughout the brain. It was absent in the organum vasculosum of the lamina terminalis. PIN staining was present in neurons of the medial preoptic area, paraventricular nucleus, medial septum, and cortex, but not in the supraoptic nucleus, septohypothalamic nucleus, or organum vasculosum of the lamina terminalis. Colocalization between PnNOS and PIN was found in the medial preoptic area, medial septum, and cortex, and less in the paraventricular nucleus. PnNOS and oxytocin were colocalized in the paraventricular nucleus and supraoptic nucleus. In hypothalamic extracts, recombinant PIN‐GST protein bound to PnNOS in the extracts and partially inhibited NOS activity. These results indicate that both nNOS variants, and their respective regulatory proteins are present and colocalize in the hypothalamic and spinal cord regions involved in penile erection. J. Comp. Neurol. 458:46–61, 2003. © 2003 Wiley‐Liss, Inc.
Intraneuronal localization of Nogo‐A in the rat
Authors: Jin Wei‐Lin , Liu Ying‐Ying , Liu Hui‐Ling , Yang Hao , Wang Ying , Jiao Xi‐Ying , Ju Gong 
Published: February 2003

AbstractNogo‐A is known to be a myelin‐associated protein with strong inhibitory effect on neurite outgrowth and has been considered one of the major factors that hinder fiber regeneration in the central nervous system. Recent studies have demonstrated widespread occurrence of nogo‐A mRNA and Nogo‐A protein in neurons. Our concurrent immunohistochemical study substantiated the widespread distribution of neuronal Nogo‐A. The present study was thus focused on its intraneuronal distribution in the central nervous system, using Western blotting, immunohistochemical, and immunogold electron microscopic techniques. Western blotting of the nucleus, cytoplasm, and membrane subcellular fractions of the cerebellum and spinal cord tissues demonstrated that all three fractions contained Nogo‐A. Nogo‐A immunoreactivity could be identified under confocal microscope in the nucleus, perikayon, and proximal dendrite and along the cell membrane. Under the electron microscope, the perikaryonal Nogo‐A immunogold particles were mainly distributed at polyribosomes and rough endoplasmic reticulum, suggesting its relationship with translation process. The immunogold particles could also be found beneath or on the plasma membrane. In the nucleus, the Nogo‐A immunogold particles were found to be localized at the chromatins of the nucleus, indicating its possible involvement in gene transcription. The presence of Nogo‐A in the nucleus was further supported by transfection of COS‐7L cells with nogo‐A. This study provides the first immunocytochemical evidence for intraneuronal distribution of Nogo‐A. Apparently, the significance of Nogo‐A in the central nervous system is far more complex than what has been envisioned. J. Comp. Neurol. 458:1–10, 2003. © 2003 Wiley‐Liss, Inc.
Role of EphA4 in defining the position of a motoneuron pool within the spinal cord
Authors: Coonan Jason R. , Bartlett Perry F. , Galea Mary P. 
Published: February 2003

AbstractThe correct assembly of the neural circuits that control movement requires the development of topographically organized pools of motoneurons within the spinal cord. The generation of a diverse array of motoneuron subtypes, which express differing transcription factors and cell‐surface receptors, allows different motoneuron pools to be segregated to specific positions during development. In this investigation, we show that the Eph receptor tyrosine kinase, EphA4, appears to be important for the correct localization of a motoneuron pool to a specific position in the spinal cord. In the spinal cord of mice deficient in EphA4, the motoneuron pool that innervates the tibialis anterior muscle of the hindlimb is caudally displaced by approximately one vertebral segment. However, despite the abnormal position of the tibialis anterior motoneuron pool in the spinal cord of EphA4‐deficient animals, the motoneurons of this pool still project to the tibialis anterior muscle of the hindlimb correctly. Additional analyses of other limb innervating motoneuron pools in the cervical and lumbar enlargements of the spinal cord of EphA4‐deficient animals revealed them to be located in the appropriate segmental positions. Furthermore, we show that EphA4 does not appear to be important for spinal motoneuron survival as stereological quantification of the number of motoneurons present in the sciatic motoneuron pool of EphA4‐deficient animals demonstrated these motoneurons to be present in the correct numbers. These observations suggest an important role for EphA4 in regulating the position of a specific motoneuron pool within the spinal cord. J. Comp. Neurol. 458:98–111, 2003. © 2003 Wiley‐Liss, Inc.
Heat transfer enhancement in round tube using wire coil: Influence of length and segmentation
Authors: Shoji Yukitsugu , Sato Kyozo , Oliver D.R. 
Published: February 2003

AbstractExperiments are performed to study heat transfer enhancement in a round tube using a wire coil as a turbulator. This paper presents the effects of length and segmentation of the wire coil. Experiments are conducted with three different wire coils (1000, 500, and 300 mm) on the effect of length. The wire coils used to measure the effect of segmentation are three different types but of the same area (500 mm × 1, 100 mm × 5, and 50 mm × 10). The wire coils are made of copper of diameter 1.5 mm. The test fluid is water. Both heat transfer and friction factor are measured and compared.From the experiments, we were able to conclude that heat transfer and friction positively correlate to length of the wire coil. Heat transfer correlations are given as Eq. (7) for length and Eq. (10) for segmentation. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(2): 99–107, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10072
Numerical simulation on liquid jet behavior issued into still air
Authors: Inamura Takao , Tsutagawa Takehito , Cho Seong Jin , Masuya Goro 
Published: February 2003

AbstractNumerical simulations have been conducted to clarify the effects of turbulence, in the onset of protrusions on liquid jet surfaces. The turbulences in the liquid jet were simulated by the Rankin vortices. The liquid jet surface was tracked numerically by the VOF method. From numerical simulations, the protrusions on the liquid jet surface are induced by the vortices in the liquid, whose rotational direction decelerates the jet surface. Despite the distance between vortices, the displacement of the liquid jet surface from the initial surface location increases linearly, in time, at almost the same growth rate. In the initial region, the growth rate of the displacement increases as the major semiaxis‐to‐minor semiaxis ratio of the ellipsoidal vortex increases. The initial growth rate of displacement is almost proportional to the vortex intensity. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(2): 141–152, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10078
Enhancement of natural convective heat transfer from tall, vertical heated plate to water
Authors: Misumi Toshiyuki , Kitamura Kenzo 
Published: February 2003

AbstractAn enhancement technique was developed for natural convection heat transfer from a tall, vertical heated plate to water. Rectangular grid fins attached to the base plate were utilized as a heat transfer promoter. These grid fins redirect the high‐temperature fluid ascending along the base plate toward the outside of the boundary layer and introduce the low‐temperature ambient fluid toward the base plate instead. The heat transfer coefficients of thus‐treated surfaces were measured and compared with a nontreated surface and a surface with conventional vertical plate‐fins. The highest performance was achieved for the experimental surfaces. In particular, the experimental surfaces with 5‐mm‐high, nonconducting grids and with 10‐mm‐high, conducting grid fins show 27% and 80% higher heat transfer coefficients compared to the turbulent heat transfer coefficients of the nontreated surface, respectively. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(2): 178–190, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10083