bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of rowing on humeral strength
Authors: Weiss Elizabeth 
Published: July 2003

AbstractThis study used an aggregate measure of robusticity (based on humeral areal and inertial cross‐sectional components) to test the hypothesis that rowing on oceans led to more robust humeri than did rowing on rivers or not rowing at all. Results confirmed the hypothesis that male ocean‐rowers had more robust humeri than did male river‐rowers or nonrowers. However, although the females from the ocean‐rowing populations did not row, they averaged more robust humeri than did females from the non‐ocean‐rowing populations. Males averaged greater robusticity than did females. The robusticity of ocean‐rowing populations, therefore, does not seem to be due solely to bone remodeling resulting from strenuous rowing. Humeral robusticity is difficult to attribute to specific activities because, in humans, upper limbs are utilized for many activities. Some populations may have more robust humeri because certain environments require greater overall activity levels in order to survive. Am J Phys Anthropol 121:000–000, 2003. © 2003 Wiley‐Liss, Inc.
Brief Communication:Age and fractal dimensions of human sagittal and coronal sutures
Authors: Lynnerup Niels , Jacobsen Jens Christian Brings 
Published: July 2003

AbstractThe fractal dimensions of human sagittal and coronal sutures were calculated on 31 complete skulls from the Terry Collection. The aim was to investigate whether the fractal dimension, relying on the whole sutural length, might yield a better description of age‐related changes in sutural morphology, as opposed to other methods of quantification, which generally rely on more arbitrary scoring systems. However, the fractal dimension did not yield better age correlations than other previously described methods. At best, the results reflected the general observation that young adults below age 40 years display an age‐related development, but that it is impossible to arrive at any precise age determinations for older adults. It seems that for some individuals, suture obliteration simply does not take place, even at an advanced age, whereas for others, suture obliteration progresses rapidly. Until a better understanding of sutural biology is reached, this will render cranial sutures only marginally useful in age determination. This does not mean, however, that investigations should not be made to elucidate more unbiased methods of sutural morphology quantification. Am J Phys Anthropol 9999:000–000, 2003. © 2003 Wiley‐Liss, Inc.
Cranial variation in the Marquesas Islands
Authors: Stefan Vincent H. , Chapman Patrick M. 
Published: July 2003

AbstractThe Marquesas Islands have traditionally been divided into a northwestern and a southeastern group, a division which reflects language dialect differences. Additionally, archaeological studies have also suggested that differences in material culture existed between the northwestern and southeastern islands. This study examines Marquesan cranial discrete and metric traits to evaluate the level of intra‐archipelago heterogeneity, and to determine if a northwest/southeast division is evident cranially.The data consist of 28 cranial discrete traits and 49 craniofacial measurements of prehistoric Marquesans. Male and female data are pooled for discrete trait and metric data, following aZ‐score standardization technique adjustment. The data represent three island samples: Nuku Hiva (northwest), Fatuiva (southeast), and a combined Tahuata/Hiva 'Oa (southeast). Of the 28 discrete traits, 16 are utilized in a mean measure of divergence analysis that provides scores of 0.259 for Fatuiva‐Tahuata/Hiva 'Oa, 1.850 for Nuku Hiva‐Fatuiva, and 1.491 for Nuku Hiva‐Tahuata/Hiva 'Oa. Of the 49 craniofacial measurements, 46 are utilized in RMET/NORM analyses, providing unbiased D2values of 0.0433 for Fatuiva‐Tahuata/Hiva 'Oa, 0.1328 for Nuku Hiva‐Fatuiva, and 0.0813 for Nuku Hiva‐Tahuata/Hiva 'Oa. The islands of the southeastern group are closer to each other than either was to the island of the northwestern group. When a sample from 'Ua Huka is included in the craniometric analysis, the unbiased D2values of 0.0829, 0.1175, and 0.0431 are calculated for 'Ua Huka and Nuku Hiva, and Fatuiva and Tahuata/Hiva 'Oa pairings, respectively, indicating a close similarity of 'Ua Huka to the southeastern islands.Mean measure of divergence analysis of cranial discrete traits as well as RMET/NORM analyses of craniometric variables reveal that differences exist between the islands of the northwestern and southeastern Marquesas Islands. These results support previous research that documented linguistic and cultural differences between these regions of the archipelago. However, the results indicate that 'Ua Huka, an island traditionally included in the northwestern Marquesas Islands, has an affinity to the southeastern Marquesas Islands, possibly due to its pivotal position as a waypoint in the Marquesas Island interaction sphere. Am J Phys Anthropol, 2003. © 2003 Wiley‐Liss, Inc.
Physical aging of polymer concrete during creep
Authors: Aniskevich K. , Hristova J. , Jansons J. 
Published: July 2003

AbstractThe long‐term creep of polymer concrete was predicted with the structural approach and with the phenomenological model of the creep of a polymer binder (polyester resin). The physical aging of polyester resin during the previous exposure of the composite at elevated temperatures and its subsequent creep was examined. The model accounted for the deceleration of relaxation processes in the polyester resin and its shrinkage. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3427–3431, 2003
Preparation and characterization of water‐extended polyester based on recycled poly(ethylene terephthalate)
Authors: Tawfik M. E. 
Published: July 2003

AbstractAn unsaturated polyester resin was prepared that was based on the reaction of oligomers obtained from the depolymerization of poly(ethylene terephthalate) waste products, with both maleic anhydride and sebacic acid. The structure of the produced polyester was compared with that prepared from the reaction of dimethyl terephthalate with both maleic anhydride and sebacic acid with IR and NMR spectroscopy. Water‐extended polyester resins were prepared from these two polyesters through curing with styrene in the presence of various amounts of water with benzoyl peroxide as an initiator. The mechanical properties of the prepared water‐extended polyesters, as well as scanning electron microscopy, were investigated. The use of water‐extended polyesters based on recycled poly(ethylene terephthalate) waste for the preparation of decorative art objects and statues was investigated. Therefore, three pharaonic statues representing Tutankhamen, Nefertiti, and a black head of a cat were prepared. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3693–3699, 2003
Characterization and properties of amphiphilic block polymer based on poly(ethylene oxide) and poly(butyl acrylate)
Authors: Wang Caiqi , Zhang Guo , Zhang Zhihao , Chen Xinfang , Tang Xinyi , Tan Huimin 
Published: July 2003

AbstractPEO‐b‐PBA [PEO: poly(ethylene oxide); PBA: poly(butyl acrylate)], an amphiphilic block copolymer, prepared by redox radical polymerization, was characterized by infrared and 1H nuclear magnetic resonance spectroscopy. The result revealed the existence of PEO and PBA segment in purified block copolymer. The thermal behavior of the block copolymer was determined by differential scanning calorimetry. With the introduction of PBA noncrystalline segment, the crystallinity of PEO was decreased. The emulsifying and water absorptive properties of PEO‐b‐PBA were also examined. It was found that the emulsifying volume and type were dependent on the amount of block copolymer and the PEO content in block copolymer. Under a certain range, the emulsifying volume increases with an increase of PEO content. The more the PEO content in block copolymer, the stronger the water absorptivity was. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3432–3436, 2003
Effect of inorganic salts on viscosity of acrylonitrile‐N‐vinylpyrrolidone copolymer solutions
Authors: Hou Chen , Wang Cheng‐Guo , Ying Liang , Cai Hua‐Su 
Published: July 2003

AbstractEffects of inorganic salts on viscosities of dimethyl sulphoxide (DMSO) solutions of acrylonitrile(AN)/N‐vinylpyrrolidone(N‐VP) copolymer are discussed. Viscosity was determined by the rotary viscosimeter. It was shown that the solution viscosity decreases quickly with addition of KCl and NaCl and the effect of NaCl is more prominent than that of KCl. As concentration of KCl and NaCl went beyond 0.025 mol/L, the viscosity showed a trend of increase. The viscosity increased considerably with addition of FeCl3 and CuCl2. Changes in solution viscosity became less obvious with addition of ZnCl2. As temperature increased, the viscosity of the copolymer solution containing NaCl decreased most quickly and the copolymer solution consisting of FeCl3 showed the slowest decrease. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3492–3495, 2003
Properties of regenerated cellulose films plasticized with α‐monoglycerides
Authors: Xiao Chaobo , Zhang Zhenjun , Zhang Jinhua , Lu Yongshang , Zhang Lina 
Published: July 2003

AbstractRegenerated cellulose (RC) films were plasticized with glycerol, glycerin α‐monobutyrate, glycerin α‐monocaproate, glycerin α‐monocaprylate, and glycerin α‐monocaprate. The structure and properties of the films were investigated by using Fourier transform IR, wide‐angle X‐ray diffraction, differential scanning calorimetry, scanning electron microscopy, and tensile tests. The experimental results showed that the addition of plasticizer enhanced the elongation at break, thermal stability, and crystallinity and lowered the tensile strength of the films. The formation of hydrogen bonds between the cellulose and plasticizers weakened the inter‐ and intra‐hydrogen bonds among cellulose molecules, leading to reduced tensile strength. These α‐monoglycerides have relatively good plasticizing effects. Compared with glycerol, the resistance against water washing of the synthesized compounds was significantly enhanced. With the increase of the carbochain length of the α‐monoglycerides, the plasticizing effect decreased but the resistance against water washing was enhanced. When the RC films were immersed in a 10% glycerin α‐monocaproate solution, the elongation at break increased to 15% and stayed at 14.8% after water washing. Glycerin α‐monocaproate might be better for plasticizing RC films than others. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3500–3505, 2003
Effect of monomer type and dangling end size on polymer network synthesis
Authors: Ward Jennifer H. , Furman Kimberly , Peppas Nicholas A. 
Published: July 2003

AbstractThe design of novel biomaterials for applications in biological recognition, drug delivery, or diagnostics requires a judicious choice of preparation conditions and methods for the production of well‐characterized 3‐dimensional structures, preferably by benign processes. In this work, the polymerization of poly(ethylene glycol) (PEG) methacrylates was examined by kinetic gelation modeling and kinetic analysis in order to ascertain the factors affecting the resulting structure. The kinetics of the polymerization and structure of the final polymer network are strongly affected by the length of the PEG graft chain. The propagation of the polymer chains becomes increasingly diffusion limited with the incorporation of longer PEG grafts. In addition, a more heterogeneous network consisting of numerous microgel regions is produced as the length of the PEG graft is increased. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3506–3519, 2003
Structure–property relationships of poly(urethane‐urea)s with ultralow monol content poly(propylene glycol) soft segments. III. influence of mixed soft segments of ultralow monol poly(propylene glycol), poly(tetramethylene ether glycol), and tri(propylene glycol)
Authors: O'Sickey Matthew J. , Lawrey Bruce D. , Wilkes Garth L. 
Published: July 2003

AbstractRecent advances in the catalyst technology associated with the production of poly(propylene glycol) (PPG) have allowed for the fabrication of ultralow monol content PPG macrodiols (Acclaim™ polyols), which are highly bifunctional and can be produced in substantially higher molecular weights and with narrower molecular weight distributions than previously possible. These factors have enabled the preparation of higher value elastomers and may allow for the first manufacture of economically attractive PPG‐based poly(urethane‐urea) (PUU) fibers. In the past, many performance polyurethane and PUU elastomers used poly(tetramethylene ether glycol) (PTMEG) for the soft segments either alone or in combination with other macrodiols. The work presented here details the investigation of the morphological features of PUU systems with mixed soft segments of PPG, PTMEG, and a low molecular analog of PPG, tri(propylene glycol) (TPG) in an effort to ascertain the influence of structural features on the mechanical and thermal properties of the elastomers. Also of interest was whether the incorporation of PPG and TPG would either prohibit or greatly hinder the formation of strain‐induced PTMEG crystallites. It was found that, even when only 60 wt % of the soft segments consisted of PTMEG, those soft segments were still able to undergo recognizable strain‐induced crystallization as detected by wide‐angle X‐ray scattering. It was also seen that, as the ratio of PPG to PTMEG was varied, there were systematic changes in the soft segment glass transition and cold crystallization characteristics. Inclusion of PPG and TPG resulted in PTMEG's diminished ability to undergo cold and strain‐induced crystallization, as seen with differential scanning calorimetry and wide‐angle X‐ray scattering. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3520–3529, 2003
Adhesion between addition‐curable silicone elastomer and nylon using diallylbisphenol A as adhesion promoter
Authors: Kerboua Rachid 
Published: July 2003

AbstractIt was found that the incorporation of a small amount of 2,2′‐diallylbisphenol A in a two‐component room‐temperature vulcanizing (RTV) silicone produced excellent adhesion on nylon substrates, whereas no adhesion was observed when this additive was excluded from the formulation. The effect of the chemical structure and the functionalities of this adhesion promoter were investigated by evaluation of several other molecules bearing both allylic and phenolic groups. No adhesion improvement was observed when 2‐allyl 4‐cumylphenol or 2‐allylphenol was used as the adhesion promoter, whereas with 2‐allylbisphenol A there was good adhesion between the two surfaces. Although it is quite clear that allyl groups react with the adhesive through the hydrosilylation reaction during the cure process of the RTV material, the interaction of the phenolic group with polymer surfaces seems to be largely dependent on the steric effect, that is, the ability of the OH group to be close enough to the plastic surface to develop a strong hydrogen bond. The minimum temperature required for adhesion to occur between nylon and RTV was determined to be in the range of 50°C–60°C. This temperature corresponds to the glass‐transition temperature of the amorphous part of the nylon. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3496–3499, 2003
Effect of silane monomer on the improvement of mechanical and degradable properties of photografted jute yarn with acrylamide
Authors: Hassan M. Masudul , Islam M. Rabiul , Sawpan Moyeenuddin A. , Khan Mubarak A. 
Published: July 2003

AbstractUV radiation was used to graft acrylamide (AA) to jute yarn in order to improve the mechanical properties. The physicomechanical properties of the grafted jute yarn were investigated. A series of solutions of different AA concentrations in methanol along with photoinitiator (Irgacure‐907, 2%) were prepared. The jute yarns were soaked in the solution for 30 min before radiation. The effect of irradiation time, concentration of monomer on polymer loading, and tensile properties of the jute yarn were studied. The highest polymer loading (22%) and tensile strength (95%) of the yarn were observed when the yarn was treated in 30% AA in methanol with 60 min of UV radiation. The surfaces of both treated and untreated jute were characterized by X‐ray photospectrometry, infrared spectroscopy, and environmental scanning electron microscopy, and it was observed that the AA reacted or deposited on the jute surface. A minute amount (1%) of silane monomer [3‐(trimethoxysilyl)‐propyl methacrylate] was used as an additive in the AA solution to further improve the mechanical properties of jute yarn. Better improvement was achieved by using 1% silane monomer. Water uptake, simulating weathering, and soil degradation tests of untreated and treated yarns were also performed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3530–3538, 2003
Effect of thermal aging on the biodegradation of PCL, PHB‐V, and their blends with starch in soil compost
Authors: Rosa Derval dos Santos , Rodrigues Túlio César , Graças Fassina Guedes Cristina das , Calil Maria Regina 
Published: July 2003

AbstractDifferent proportions of starch were blended with poly(β‐hydroxybutyrate)‐co‐poly(β‐hydroxyvalerate) (PHB‐V) or poly(ε‐caprolactone) (PCL) by extrusion, and the mechanical (maximum tensile strength, elongation at break and Young's modulus) and thermal properties (by differential scanning calorimetry) were determined. The biodegradability of the blends in soil compost was also assessed after thermal aging for 192, 425, and 600 h at different temperatures. The maximum tensile strength of the PCL50 blend (containing 50% starch) was 35% lower than that of PCL and that of the PHB‐V50 blend was 60% lower than that of PHB‐V without thermal aging. PHB‐V blends were more biodegradable than PCL blends. For the blends prepared, only the biodegradation of PHB‐V25 was affected by thermal aging. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3539–3546, 2003
Thermal behavior and cured products of bis(4‐maleimidodiphenyl)methane, bis(isomaleimidodiphenyl)methane and 4,4′‐diaminodiphenyl methane mixtures
Authors: Gaina V. , Gaina C. , Paraschiv I. 
Published: July 2003

AbstractThe thermal behavior of mixtures of bis(4‐maleimidophenyl) (A) with bis(4‐isomaleimidophenyl)methane (C) and their mixture with 4,4′‐diaminodiphenyl methane (D) were investigated by differential scanning calorimetry. The study of the binary system A/C in different proportions led us to determine an eutectic mixture at a molar fraction of C in the range of 0.7–0.9. The ternary ACD mixtures showed themselves able to participate in three principal reactions: polyaddition, ring‐opening addition, and homopolymerization. In each mixture studied the addition of diamine changed the melting point and maximum polymerization temperatures in the sense of a general decrease. The properties of the networks were studied by thermal analysis and through evaluation of water absorption. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3547–3556, 2003
Changes in morphology and properties by grafting reaction in PP/EOR/CaCO3 ternary composites
Authors: Premphet‐Sirisinha K. , Preechachon I. 
Published: July 2003

AbstractThe phase morphology and mechanical properties of polypropylene (PP) composites containing ethylene–octene elastomer (EOR) and calcium carbonate (CaCO3) filler were investigated by comparing the toughening effect of unmodified EOR with EOR grafted with maleic anhydride (EOR–MA). EORs of various MA contents were prepared by free‐radical grafting of MA onto the EOR backbone using a reactive extrusion process. The composite morphology was directly explored by scanning electron microscopy technique and indirectly explored by differential scanning calorimetry and dynamic mechanical analysis. Separate dispersion of the elastomer and filler particles was achieved by using unmodified EOR. Modification of EOR by maleic anhydride grafting resulted in encapsulation of the filler particles. The mechanical properties of the composites were found to depend mainly on composite morphology and composition and, to a lesser degree, on maleic anhydride concentration. The results of this study showed that when composites contained an equal or higher amount of elastomer relative to filler, a composite with a separate dispersion structure was preferred. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3557–3562, 2003
Sonochemical polymerization of acrylic acid and acrylamide in the presence of a new redox system— A comparative study
Authors: Anbarasan R. , Jayaseharan J. , Sudha M. , Gopalan A. 
Published: July 2003

AbstractAcrylic acid and acrylamide were polymerized by a peroxydisulfate–suberic acid redox system under a nitrogen atmosphere both in the presence and in the absence of ultrasound (at constant frequency). The rate of polymerization was determined for different concentrations of monomer, initiator, and activator and for different percentages of ultrasonic intensity. The polymers were characterized by X‐ray diffraction and 1H‐NMR spectroscopy. A probable mechanism is proposed to explain the experimental results obtained. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3685–3692, 2003
Radiation effects on methyl vinyl polysilicone foam
Authors: Huang Wei , Fu Yibei , Wang Chaoyang , Xu Yunshu , Chen Yinliang 
Published: July 2003

AbstractThe effects on methyl vinyl polysilicone foam of 60Co γ‐ray radiation at room temperature was studied in air, in vacuo, and in an inert gas atmosphere. The unirradiated and irradiated samples were analyzed by Fourier transform infrared spectroscopy, scanning electron microscopy, pyrolysis gas chromatography/mass spectroscopy, and thermogravimetric analysis, and the gas products after radiation were analyzed by gas chromatography/mass spectroscopy. The changes of the gel fraction, compression properties, and the stress–relaxation ratio with dose for irradiated samples were observed. The results show that the second crosslinking reaction in the polysilicone after chemical crosslinking took place at a low dose (2 × 105 Gy), but radiation degradation was predominant, with the dose increasing step by step. The mechanical properties of polysilicone foam gradually became low grade after it was irradiated by any dose in excess of 2 × 105 Gy. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3437–3441, 2003
Effect of hydrophobic hexafluoroisopropylidene group on the water sorption behaviors of rigid poly(p‐phenylene pyromellitimide) polyimide thin films
Authors: Seo Jongchul , Yup Lee Sang , Jang Wonbong , Han Haksoo 
Published: July 2003

AbstractWe prepared poly(p‐phenylene pyromellitimide) (PMDA–PDA), poly(p‐phenylene 4,4′‐hexafluoroisopropylidene diphthalimide), and their copolyimides with various compositions to explore the relationship between the water sorption and structure. The water sorption behaviors were gravimetrically investigated as a function of composition and temperature and interpreted with a Fickian diffusion model in films. Overall, the water sorption behaviors were strongly dependent on the changes in morphological structure, which originated from the variations in composition. When the content of the bulky hexafluoroisopropylidene group (6FDA) was increased, the water uptake decreased from 5.80 to 3.18 wt %, whereas the diffusion coefficient increased from 3.6 × 10−10 to 11.3 × 10−10 cm2/s. The relatively high water uptake in the PMDA–PDA polyimide film was successfully healed by the incorporation of 6FDA, which may have resulted from the increases in the intermolecular packing order and hydrophobicity. The degree of orientation and crystallinity, which are in‐plane characteristics, were directly correlated to the diffusion coefficient and activation energy in the polyimide film. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3442–3446, 2003