bluuebunny/crossref_metadata_2025_split huggingface dataset:
Understanding polymeric amylose retrogradation in presence of additives
Authors: Chaudhary Deeptangshu S. , Adhikari Benu P. 
Published: October 2009

AbstractPolymeric aging in starch is an important equilibrating process leading to long‐chain amylose recrystallization and anisotropic properties of material made from starch. Investigations into a number of plasticizers and hydrocolloids showed that their water retention/binding capability influence the starch polymer's crystallinity. Addition of up to 8 wt % glycerol and 3 wt % xylitol acted as an antiplasticizer and apparently increased the total crystalline phase, which reduced the degree of elongation of amylose matrix by 15%. Maltodextrin and xanthan gum also reduced matrix elongation capability but X‐ray diffraction (XRD) analysis showed samples with varying crystallinity, and the extent of crystallinity did not correlate with respective tensile properties. Additives such as maltodextrin, with similar molecular structure as amylose, were ineffective in increasing degree of elongation even at 15 wt % addition rate, because of formation of pockets of crystalline region, as observed by XRD analysis. Both xylitol and xanthan gum samples showed similar tensile strength and elongation properties, but the water retention capability of xylitol‐filled starch samples was about 27% lower than xanthan gum samples, at their respective higher concentrations. A dynamic structural unit is proposed to satisfy the isotropic increase in tensile strength and degree of elongation in oriented starch matrix. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Novel process for isolating fibrils from cellulose fibers by high‐intensity ultrasonication. II. Fibril characterization
Authors: Cheng Qingzheng , Wang Siqun , Han Qingyou 
Published: October 2009

AbstractHigh‐intensity ultrasonication with a batch process was used to isolate fibrils from several cellulose sources, and a mixture of microscale and nanoscale fibrils was obtained. The geometrical characteristics of the fibrils were investigated with polarized light microscopy, scanning electron microscopy, and atomic force microscopy. The results show that small fibrils with diameters ranging from about 30 nm to several micrometers were peeled from the fibers. Some fibrils were isolated from the fibers, whereas some were still on the fiber surfaces. The lengths of untreated and treated cellulose fibers were investigated by a fiber size analyzer. The crystallinities of some cellulose fibers were evaluated by wide‐angle X‐ray diffraction and Fourier transform infrared spectroscopy. The high‐intensity ultrasonication technique is an environmentally benign method and a simplified process that conducts fiber isolation and chemical modification simultaneously and helps significantly reduce the production cost of cellulose nanofibers and their composites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation of carbon black/polypropylene nanocomposite with low percolation threshold using mild blending method
Authors: Li Wei , Liu Zheng‐Ying , Yang Ming‐Bo 
Published: October 2009

AbstractA new approach, mild blending method, to prepare carbon black (CB) filled polypropylene (PP) nanocomposite using CB aqueous suspension was reported in this study. In this compounding process, the CB particles were first dispersed in aqueous suspension by using an ultrasonic irradiation. Subsequently, the CB suspension was blended with melting PP using an extruder with low shear strength screw configuration, followed by removing the vapor from the vent by vacuum. The morphological observation showed that the CB particles were dispersed at a nanometer level in the nanocomposites as they were in aqueous suspension and distributed homogeneously in PP matrix. The CB/PP nanocomposite prepared by this method exhibited a very low percolation threshold, i.e., 2.49 vol %, and a high‐critical resistance exponent t (t = 5.82). These phenomena, which deviated from the classical percolation theory, were likely to come down to the homogeneous distribution of CB particles and the tunneling conduction. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Coatings on textiles for Cu(In,Ga)Se2 photovoltaic cell formation on textile carriers: Preparation of Cu(In,Ga)Se2 solar cells on glass‐fiber textiles
Authors: Knittel Dierk , Köntges Marc , Heinemeyer Frank , Schollmeyer Eckhard 
Published: October 2009

AbstractResults are presented on the construction of a thin‐layer photovoltaic cell on glass‐fiber fabric. The unevenness of the fabric was first smoothed by the application of a high‐temperature stable resin before photovoltaic layer deposition. We obtained an efficiency of light‐to‐current conversion of more than 8%. This constitutes a remarkably high value for a photovoltaic cell on a flexible substrate. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Miniemulsion copolymerizations of methyl methacrylate and butyl acrylate in the presence of reactive costabilizer
Authors: Lin C. T. , Chiu W. Y. , Lu H. C. , Meliana Y. , Chern C. S. 
Published: October 2009

AbstractThe storage stability and free radical polymerizations of miniemulsions comprising methyl methacrylate (MMA), butyl acrylate (BA), and a reactive costabilizer stearyl methacrylate (SMA) were investigated. The Ostwald ripening rate increases with increasing MMA content in the monomer mixture. Both the pseudo‐two‐component model and empirical equation with one adjustable parameter k adequately predicted the Ostwald ripening rate data. For the empirical model, the least‐squares best fit technique gave a value of k equal to 677.5 and values of Ostwald ripening rate and water solubility equal to (8.8 ± 0.2) × 10−21 cm3/s and 1.8 × 10−9 cm3/cm3 for SMA, respectively. These two models were combined to impart some physical insight to the parameter k. The kinetic studies showed that the polymerization rate increased with increasing MMA content. This is closely related to the nature of the constituent monomers MMA and BA and the particle nucleation mechanisms. The reactive costabilizer SMA is not hydrophobic enough to completely eliminate the Ostwald ripening effect, thereby increasing the probability of polymer reactions in the continuous aqueous phase. Thus, in addition to monomer droplet nucleation, particle nuclei can be generated in the aqueous phase via homogeneous nucleation. The extent of homogeneous nucleation increased with increasing MMA content and, as a result, the number of reaction loci available for the major polymerization to take place followed the same trend. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
NaOH/urea aqueous solutions improving properties of regenerated‐cellulosic fabrics
Authors: Ehrhardt Anelise , Bui Huong Mai , Duelli Heinz , Bechtold Thomas 
Published: October 2009

AbstractThe application of sodium hydroxide and sodium hydroxide containing urea solutions has been utilized for regenerated‐cellulosic material activation. The treatments resulted in the reorganization of cellulose fibers, hence accessibility and reactivity. In this study, sodium hydroxide–urea solutions were applied to lyocell and viscose‐knitted fabrics as finishing treatment to improve the accessibility and physical properties of textiles. Besides the mixtures, different concentrations of sole sodium hydroxide and sole urea treatment were applied. The different concentrations of urea, sodium hydroxide, and sodium hydroxide–urea mixtures were used with small increment to detect suitable concentrations and mixture ratios applied for fabrics modification. The results showed the effectiveness of applying the mixture solutions of alkali–urea particularly to CV‐knitted fabrics for improving pilling behavior, whereas for CLY fabrics, the standard alkali solutions showed the best pilling performance. The utilization of urea and sodium hydroxide–urea mixture played an important role for regenerated‐cellulosic fabrics where high alkali concentrations is not preferred to avoid fabric damages and where a mixture system could inhibit some of these aspects. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation of asymmetric chitosan hollow fiber membrane and its pervaporation performance for dimethyl carbonate/methanol mixtures
Authors: Xiao Tonghu , Xu Xiaoli , Cao Yiming , Deng Maicun , Chen Shanmei , Jie Xingming 
Published: October 2009

AbstractChitosan hollow fiber membranes (CHFMs) were successfully fabricated by a phase inversion method. The CHFMs obtained by ethanol–hexane exchange drying displayed integrally skinned asymmetric morphologies by field‐emission scanning electron microscope observation. The CHFMs could be used for the pervaporation separation of dimethyl carbonate (DMC)/methanol mixtures. Swelling properties of the polymer material were investigated, and the effects of feed composition and operating temperature on the pervaporation separation performance of the CHFMs were evaluated. The relationship of permeation flux and temperature was in agreement with the Arrhenius equation. It was demonstrated that the integrally skinned asymmetric CHFMs exhibited an effective method for the separation of DMC/methanol azeotropic mixtures. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Mechanical, optical, and electrical properties of cellulosic semiconductor nanocomposites
Authors: Hassan Mohammad L. , Ward Azza A. , Eid Mahmoud A. 
Published: October 2009

AbstractPhotoluminescent cellulose fibers were prepared by impregnation of bleached bagasse pulp with the different cadmium and zinc sulfides nanostructures, namely, CdS, ZnS, CdS/ZnS, ZnS/CdS (Core/shell nanostructures), CdS/ZnS/CdS and ZnS/CdS/ZnS multilayered nanostructures. The prepared cellulosic nanocomposites were characterized regarding strength properties (tensile strength, tensile energy absorption, and burst resistance), optical properties (fluorescence emission), thermal stability, and dielectric properties. The strength properties of paper sheets nanocomposites impregnated with different nanoparticles solutions were noticeably decreased in spite of the very low loading of the fibers with the semiconductor nanoparticles. The decrease in tensile index, tensile energy absorption, and burst index of paper sheets nanocomposites are found to be ranged from 12–27, 13–36, and 11–38 %, respectively. The different paper sheets nanocomposites showed fluorescence emission different from the as prepared polyethyleneimine‐stabilized nanoparticles. Thermogravimetric analysis results showed that: the semiconductor nanoparticles did not affect the onset degradation temperature of cellulosic fibers but it caused faster termination of the main degradation step. The dielectric loss and the dc‐conductivity of cellulosic fibers increased as a result of impregnating the fibers. The nature of the nanoparticles and the properties of the interphases strongly influenced the dielectric properties of the cellulosic/semiconductors nanocomposites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Alkali pretreatment and resin finishing of lyocell: Effect of sodium hydroxide pretreatments
Authors: Kongdee Arunee , Manian Avinash P. , Lenninger Margit , Schlangen Joerg , Bechtold Thomas 
Published: October 2009

AbstractLyocell fabric samples were pretreated with 2–8 mol/L sodium hydroxide (NaOH) and then resin‐finished with dimethyloldihydroxyethylene urea, dimethyl dihydroxyethylene urea, and dimethylol urea based products. The resin‐finishing treatments caused changes in the substrate properties, such as reduced accessibility, improved crease recovery, and reduced work of rupture and abrasion resistance. Differences were observed between resin‐finished substrates as a function of the crosslinker type, and they were attributed to the influence of the crosslinker content and crosslink length in the substrates. The alkali pretreatments influenced the effects of resin finishing. A significant enhancement of the crosslinker penetration appeared within the substrates pretreated with 4 mol/L NaOH. Pretreatments with 6 and 8 mol/L NaOH also enhanced the crosslinker penetration, but the depth of catalyst penetration appeared to exceed that of the crosslinker; leading to demixing between the two components within the substrates. The penetration depth of a direct dye, C.I. Direct Red 81, appeared lower than that of the crosslinker in the alkali‐pretreated substrates. Pretreatments with NaOH in the range of 4–8 mol/L appeared to create gradients of accessibility within fibers and yarns of lyocell fabrics, with the depth of reagent penetration increasing in the following order: C.I. Direct Red 81 < crosslinker < catalyst. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Properties of a poly(acrylamide‐co‐diallyl dimethyl ammonium chloride) hydrogel synthesized in a water–ionic liquid binary system
Authors: Zhao Qian , Sun Jianzhong , Chen Songwei , Zhou Qiyun 
Published: October 2009

AbstractA novel copolymer hydrogel, poly(acrylamide‐co‐diallyl dimethyl ammonium chloride), was prepared by the radical copolymerization of acrylamide and diallyl dimethyl ammonium chloride in an ionic liquid (IL)–water binary system in the presence of the crosslinker N,N′‐methylene bisacrylamide. The equilibrium swelling ratios of the hydrogels synthesized in the IL–water binary system increased with the content of IL and were remarkably higher than that of the gel synthesized in water. Differential scanning calorimetry measurements showed that the glass‐transition temperatures of the dry hydrogels that were synthesized in the IL–water binary system were remarkably lower than that of the gel synthesized in pure water. The mechanical properties of the gels synthesized in both water and the IL–water binary system were characterized with a universal material‐testing machine. The results show that fracture toughness of the hydrogels was improved when they were synthesized in the IL–water binary system. The gel shrank under a direct‐current electric field. The response rates of the gels that were synthesized with the IL–water binary system were faster than that of the gel synthesized in water. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Multiple active site Monte Carlo model for heterogeneous Ziegler‐Natta propylene polymerization
Authors: Luo Zheng‐Hong , Shi De‐Pan , Zhu Yong 
Published: October 2009

AbstractIn this study, the kinetics of propylene polymerization catalyzed with the fourth heterogeneous Ziegler‐Natta catalyst is studied. More than one type of active site is present in the propylene polymerization based on an analysis of the GPC curves. A multiple active site kinetic model (MSmodel) is proposed by using Monte Carlo technique. Good agreements in the polymerization kinetics are achieved for fitting the kinetic profiles with the MSmodel. In addition, the MSmodel is used to describe the dynamic evolutions of the active sites and their effects on the propylene polymerization. The simulated results indicate that different types of active sites have different polymerization kinetics and the site type can affect the propylene polymerization kinetics. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Long‐term aging in a commercial aerospace composite sample: Chemical and physical changes
Authors: Tian Wendy , Hodgkin Jonathan 
Published: October 2009

AbstractA section of a carbon‐fiber‐reinforced composite horizontal stabilizer skin from a 737‐200 aircraft that had been in service for 20 years was analyzed with Fourier transform infrared spectroscopy and dynamic mechanical thermal analysis in an effort to determine the molecular changes that occurred in the epoxy matrix resin over the service life. Comparisons were made with a similar matrix resin system that had been aged under various accelerating conditions. As expected, the results showed that the molecular changes were slight and occurred only on the unpainted (internal) surface areas of the composite. The changes in the commercial materials during the in‐service aging were most similar to those in a composite that had been artificially aged at 120°C for 3000 h, but they included two chemical changes not seen previously. There was an increase in the number of aliphatic hydrocarbon molecules (a fuel chemical) as well as a decrease in the number of molecules containing SO2 units. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
JAVENGA: JAva‐based Visualization Environment for Network and Graph Algorithms
Authors: Baloukas Thanasis 
Published: October 2009

AbstractThis paper presents JAVENGA, which is an acronym for JAva‐based Visualization Environment for Network and Graph Algorithms. It is a new visualization software for educational purposes. It includes visualizations of many well‐known graph and network algorithms. However, besides simple algorithms the tool also illustrates a visualization of a quite complex one, such as the Network Simplex algorithm. The recommended tool includes a graph editor where directed and undirected graphs can be drawn, it allows users to give input to an algorithm and then see its visualization in a user‐controlled way, and finally it incorporates a solution window where one can see the values of variables at each step of algorithm execution. JAVENGA, as its name states, has been implemented in Java language and it can be run either as an applet or as a Java application. Further, one can execute the program either locally or remotely via the Web. It can be used by instructors as auxiliary teaching material in the context of a graph theory or network optimization course. Besides, instructors can use the tool to grade students' assignments or exams. Students can also use the software in a self‐learning approach. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 255–268, 2012
Racial differences in follow‐up of abnormal mammography findings among economically disadvantaged women
Authors: Adams Swann A. , Smith Emily R. , Hardin James , Prabhu‐Das Irene , Fulton Jeanette , Hebert James R. 
Published: October 2009

AbstractBACKGROUND:In the United States, and particularly in South Carolina, African‐American women suffer disproportionately higher mortality rates from breast cancer than European‐American women. The timeliness of patient adherence to the follow‐up of mammographic abnormalities may influence prognosis and survival. The objective of the current investigation was to examine racial differences in the completion and completion time of a diagnostic workup after the finding of a suspicious breast abnormality.METHODS:Study participants of the Best Chance Network, a statewide service program that provides free mammography screening to economically disadvantaged and medically underserved women, were included in the study. Racial differences in tumor characteristics and adherence to recommended workup were tested using chi‐square tests and t tests. Logistic and Cox regression modeling was used to assess the relation between workup completion and other factors among African‐American women and European‐American women.RESULTS:Completion of the workup was associated with the number of previous procedures and income, and no significant differences were noted by race. The amount of time to completion of the workup was influenced by previous procedures, income, and race. After accounting for completion time, African‐American women were 12% less likely than European‐American women to complete the recommended workup (hazard ratio, 0.88; P = .01).CONCLUSIONS:The results from this study established a racial disparity in the time to completion of a diagnostic workup among Best Chance Network participants. These findings highlight the importance of understanding the factors associated with delays in and adherence to completing the recommended workup when breast abnormalities are detected in mammograms. Cancer 2009. © 2009 American Cancer Society.
Myoepithelial carcinoma of the parotid gland metastatic to the kidney: Case report and review of the literature
Authors: Wang Zhiqin , Herrington Bruce , Schwartz Mary R. , Laucirica Rodolfo 
Published: October 2009

AbstractMyoepithelial carcinoma is a rare locally aggressive malignant neoplasm of the salivary glands. The tumor is composed almost exclusively of tumor cells with myoepithelial differentiation and characterized by infiltrative growth and potential for distant metastasis. Tumor cells often display morphologic heterogeneity with a wide range of cytomorphologic features, such as epithelioid, plasmacytoid, spindle, and clear cell types, making its recognition challenging. Only limited reports on its metastatic behavior are available in the literature. We describe a case of metastatic myoepithelial carcinoma of the kidney from the parotid gland diagnosed by computed tomography guided fine‐needle aspiration biopsy. Immunochemical studies are important to confirm myoepithelial differentiation of the tumor cells. Knowledge of the clinical history, radiographic characterization, andmorphological correlation with the primary tumor are emphasized. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.
Modified fine‐needle aspiration technique for diagnosis of granulomatous skin lesions with special reference to leprosy and cutaneous tuberculosis
Authors: Mehdi Ghazala , Maheshwari Veena , Ansari Hena A. , Saxena Sonal , Sharma Rajeev 
Published: October 2009

AbstractSkin infections are commonly assessed by slit skin or scrape methods. Fine‐needle aspiration biopsy (FNAB) is highly effective especially with blanching of skin to ensure good yield and reduced bleeding. The aim of this study was to assess usefulness of cytology, especially modified FNAB technique, in diagnosis of leprosy and cutaneous tuberculosis and to identify specific cytological characteristics for diagnosis and classification. The study was conducted on 40 patients—25 cases of leprosy and 15 cases of cutaneous tuberculosis. Smears were prepared using modified FNAB technique, slit skin, and scrape methods (depending on type of lesion). Cytological diagnosis was confirmed by histopathology where the Ridley‐Jopling system was used to classify cases of leprosy. A similar attempt was made for diagnosis and classification of leprosy on cytology. Diagnoses rendered by both modalities were compared to assess the efficacy of cytological examination. Cytological diagnosis was made in 23 cases of leprosy and 12 cases of cutaneous tuberculosis. The smears showed good cellularity. A broad division into tuberculoid and lepromatous leprosy could be made fairly accurately on cytology. Maximum agreement among clinical, cytological, and histopathological diagnosis was observed in cases of tuberculoid leprosy. Smears of cutaneous tuberculosis were characterized by epithelioid cell granulomas with caseation. Overall accuracy of diagnosis was 92% in leprosy and 80% in tuberculosis. FNAB is an inexpensive and accurate procedure for diagnosis of leprosy and cutaneous tuberculosis. The modified technique yields good results. However, clinical correlation, acid‐fast staining, and culture are essential as they provide valuable supportive information. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.