bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polyethylene/aluminum nanocomposites: Improvement of dielectric strength by nanoparticle surface modification
Authors: Huang Xingyi , Ma Zhisen , Wang Yaqun , Jiang Pingkai , Yin Yi , Li Zhe 
Published: May 2009

AbstractThe effect of the surface modification with a silane coupling agent (octyl‐trimethoxysilane) of aluminum (Al) nanoparticles on the dielectric breakdown behaviors of polyethylene (PE)/Al nanocomposites was investigated in comparison of the influence of the improvement of the interfacial adhesion between Al nanoparticles and PE using a compatibilizer (maleic anhydride grafted polyethylene). It was found that when compared with the other modification approaches, the surface‐treated Al nanofiller with the silane coupling agent makes it possible for the PE/Al nanocomposites to still keep the relatively higher breakdown strength even in the higher Al loading level above 14 vol %, which can be understood in terms of the better interfacial adhesion between the surface‐treated particle dispersion and the matrix. The combined effects of the Al nanoparticles on the different factors which influence the dielectric breakdown processes in polymer matrix such as microstructure, conductivity, and crystallinity of the nanocomposites were discussed in detail. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Thermo‐responsive injectable hydrogel system based on poly(N‐isopropylacrylamide‐co‐vinylphosphonic acid). I. Biomineralization and protein delivery
Authors: Kim So Yeon , Lee Sang Cheon 
Published: May 2009

AbstractTo achieve the injectable hydrogel system in order to improve bone regeneration by locally delivering a protein drug including bone morphogenetic proteins, thermo‐responsive injectable hydrogels composed of N‐isopropylacrylamide (NIPAAm) and vinyl phosphonic acid (VPAc) were prepared. The P(NIPAAm‐co‐VPAc) hydrogels were also biomineralized by urea‐mediation method to create functional polymer hydrogels that deliver the protein drug and mimic the bone extracellular matrix. The loosely cross‐linked P(NIPAAm‐co‐VPAc) hydrogels were pliable and fluid‐like at room temperature and could be injected through a small‐diameter aperture. The lower critical solution temperature (LCST) of P(NIPAAm‐co‐VPAc) hydrogel was influenced by the monomer ratio of NIPAAm/VPAc and the hydrogel with a 96/4 molar ratio of NIPAAm/VPAc exhibited an LCST of ∼34.5°C. Water content was influenced by temperature, NIPAAm/VPAc monomer ratio, and biomineralization; however, all hydrogels maintained more than about 77% of the water content even at 37°C. In a cytotoxicity study, the P(NIPAAm‐co‐VPAc) and biomineralized P(NIPAAm‐co‐VPAc) hydrogels did not significantly affect cell viability. The loading content of bovine serum albumin in hydrogel, which was used as a model drug, gradually increased with the amount of VPAc in the hydrogel owing to the ionic interaction between VPAc groups and BSA molecules. In addition, the release behavior of BSA from the P(NIPAAm‐co‐VPAc) hydrogels was mainly influenced by the drug loading content, water content, and biomineralization of the hydrogels. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Micromorphology of macromolecular superabsorbent polymer and its fractal characteristics
Authors: Yunkai Li , Tingwu Xu , Zhiyun Ouyang , Xiongcai Lin , Honglu Liu , Zhongyong Hao , Peiling Yang 
Published: May 2009

AbstractSuperabsorbent polymer (SAP) can absorb a solution of 10‐folds to 1000‐folds as much as its own weight. Its micromorphology directly affects its water absorption mechanism and absorption characteristics. In this work, we selected three types of polymer products for research analysis: KH (sodium polyacrylate‐type), HLM (polyacrylamide‐type), and AS (polyacrylamide‐kaliumcrylic acid‐crosslinking‐copolymer‐type). The environmental scanning electronic microscope (ESEM) method and the fractal theory are applied for studying the micromorphology of the three types of SAPs. The results show that KH possesses the highest water absorption multiplying factor and HLM possesses the lowest one. Under the condition of repeated water absorption and water release, the structure of HLM hydrogel transfers from gridding membrane to network structure. Various types of cation solutions significantly affect the characteristics of micromorphology of HLM hydrogel, and both uniqueness and diversity prevail. Under the condition of repeated water absorption and water release, the swelling multiplying factor of HLM in deionized water abides by an “inverted U” distribution. The water absorption multiplying factor for the third time is the largest one. This is primarily caused by both reduction of resilience of crosslinking network and dissolution of polymer on the surface of hydrogel under the condition of repeated water absorption and water release. The boundary of hydrogel pore network of the three types of SAPs possesses fractal characteristics. The number of fractal dimensions is as follows: fractal dimension of HLM < fractal dimension of AS < fractal dimension of KH. With the increase of the number of repeated water absorption and water release, the number of fractal dimensions of cross‐sectional pore boundary reduces, that is, T1 (1.3848) > T3 (1.2100) > T5 (1.1226). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Adsorption of Hg2+ on a novel chelating fiber prepared by preirradiation grafting and amination
Authors: Yang Ying , Ma Nianfang , Zhang Qikun , Chen Shuixia 
Published: May 2009

AbstractA novel chelating fiber was prepared by the irradiation‐induced grafting copolymerization of glycidyl methacrylate on polypropylene fiber and consequent amination with diethylenetriamine. The effects of the reaction conditions, such as reaction time, temperature, and monomer concentration, on the degree of grafting were investigated. The optimal conditions for grafting were found to be 3 h, 100°C, and a 50% (v/v) glycidyl methacrylate concentration in tetrahydrofuran solution. This fiber showed good adsorption performance at different concentrations of Hg2+, in particular for trace Hg2+. Under the adsorption conditions of pH = 4, initial concentration = 1000 mg/L, and time = 20 h, the adsorption capacity of the chelating fiber for Hg2+ reached 785.28 mg/g. It completely adsorbed the Hg2+ ions in solution within a short contact time, showing a very high adsorption rate for Hg2+. Furthermore, the chelating fiber also had a high selectivity for mercury, whereas Cu2+ coexisted in different concentrations. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Alkali treatments of lyocell in continuous processes. I. Effects of temperature and alkali concentration on the treatments of plain woven fabrics
Authors: Siroky Jan , Manian Avinash P. , Siroka Barbora , Abu‐Rous Mohammad , Schlangen Joerg , Blackburn Richard S. , Bechtold Thomas 
Published: May 2009

AbstractExperiments were conducted that were designed to study the influence of various process parameters on the properties of lyocell fabrics treated with NaOH solutions in a continuous process. The process parameters of interest were the fabric type (plain, twill, or sateen woven), alkali concentration, tension on the fabric, temperature, and duration of the treatment. In this article, we present the first set of results from these experiments and examine the effect of NaOH concentration, temperature, and tension in the continuous alkali treatments of plain woven lyocell fabrics. Alkali treatments caused fiber swelling in the fabrics to extents governed by the alkali concentration and temperature of the treatment liquors. Fiber swelling caused fabric shrinkage, which resulted in changes to the fabric macroscopic structure and properties. Changes were observed in the flexural rigidity, water retention, crease recovery, strength, and abrasion resistance of the fabrics to extents governed predominantly by swelling‐related changes to the fabric structure. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Bottleneck for reactive molar mass in the polymerization of propylene oxide initiated with potassium t‐butoxide
Authors: Yang Pengfei , Zhu Xuwei , Yu Yanhong , Xia Yong mei , Li Tianduo 
Published: May 2009

AbstractThe anionic polymerization of propylene oxide was investigated with potassium t‐butoxide as an initiator, and the solvent hexamethyl phosphoric triamide was used in controlling experiments. The relative molar mass limit of the products was determined as about 2700, and the CC double bond was found to exist by NMR. In situ Fourier transform infrared spectroscopy was used to monitor the whole polymerization process until the absorbance reached a constant value and the system reached equilibrium. However, propylene oxide still existed in the system, and alkoxide was detected in the reaction system by 23Na‐NMR. On the basis of these results, we deduced that the residual alkoxide was not active enough to initiate propylene oxide polymerization in the near end of the polymerization. Therefore, there might have been another factor that limited the increase of the relative molar mass of poly(propylene oxide) in addition to chain transfer. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis of polyimide microparticles by dispersion polymerization
Authors: Ni Xiao‐Wei , Shen Hui , Chen Li , Wu Gang , Lu Rong , Miyakoshi Tetsuo 
Published: May 2009

AbstractWe synthesized polyimide (PI) microparticles by a reaction between benzophenone‐3,3,4,4‐tetracarboxylic dianhydride and 4,4′‐diaminodiphenyl ether using polyvinylpyrrolidone as a dispersant in four different organic solvents, at different temperatures, with different amounts of the dispersing agent, and with different concentrations of monomers. After dispersion polymerization, PI microparticles in the size range 200–800 nm were obtained. Absorptions at 1775 and 1720 cm−1, due to the CO group of PI, and at 1375 cm−1, caused by the stretching vibration of the CN group due to a lactam ring, were observed in the IR spectrum, which suggested the successful synthesis of PI particles. Scanning electron microscopy analysis of microparticle morphology showed that the PI particle sizes increased with increasing temperature, concentration of dispersant, and concentration of monomers. In addition, the thermal stability is also discussed on the basis of the results of simultaneous Differential Scanning Calorimetry Modulated TA Instruments (DSC–TA) measurement. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Influence of absorbed moisture on antifelting property of wool treated with atmospheric pressure plasma
Authors: Xu Helan , Peng Shujing , Wang Chunxia , Yao Lan , Sun Jie , Ji Feng , Qiu Yiping 
Published: May 2009

AbstractTo determine the effect of moisture regain of wool on atmospheric pressure plasma treatment results, wool fibers and fabrics conditioned in 100% relative humidity (RH) and 65% RH were treated by an atmospheric pressure plasma jet with pure helium and helium/oxygen mixed gas, respectively. Scanning electron microscope (SEM) indicated that scales of wool fiber were smoothened for fibers conditioned in the 100% RH. X‐ray photoelectron spectroscopy (XPS) showed that carbon content decreased substantially after the plasma treatment. Surface chemical composition of 100% RH conditioned groups changed more significantly than the 65% RH conditioned groups. Water contact angle decreased significantly after the plasma treatments. In shrinkage test, plasma‐treated wool fabrics preconditioned in 100% RH showed the lowest shrinkage ratios of 5% and 6%, below 8% is required for machine‐washable wool fabrics according to ISO standard. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Exploring the interactions between flood defence maintenance works and river habitats: the use of River Habitat Survey data
Authors: Harvey Gemma L. , Wallerstein Nicholas P. 
Published: May 2009

Abstract
More extensive physical management of rivers in response to increasing flood risk, and action to improve the ecological quality of rivers represent two major, and potentially conflicting, challenges.
Improved understanding of the interactions between flood defence works and habitat structure must be achieved in order to satisfy both of these demands in the context of flood risk management and habitat improvement.
This paper examines the ‘extensive’ and ‘intensive’ use of data derived from a standardized method of assessing habitat character to explore the effects of flood risk maintenance works on river habitat quality.
Analysis of the UK River Habitat Survey (RHS) data set reveals some broad trends towards reduced habitat heterogeneity associated with recent flood defence works such as dredging and weed‐cutting.
These observations correspond with published localized experimental work and suggest that the RHS database can be a useful resource for identifying relationships at relatively broad scales.
Applying the RHS methodology at finer spatial scales for sites experiencing continuing maintenance reveals contrasting results and highlights some key methodological issues; these include the availability and selection of high quality benchmark conditions, the legacy of past management, lag times associated with maintenance and recovery, and recording of marginal habitat features.
Small modifications to the RHS method could enable calculation of more detailed habitat indices while maintaining comparability with the national dataset.
If the issues identified in this paper can be addressed or accounted for, RHS could be an important tool for assessing the relationship between flood defence management and new statutory obligations for ecological improvement.
Copyright © 2009 John Wiley & Sons, Ltd.
Zur inneren Standsicherheit eines Fangedamms
Authors: Hauser Carsten , Walz Bernhard , Thienert Christian , Pulsfort Matthias 
Published: May 2009

AbstractAuf der Grundlage der Erkenntnisse aus bodenmechanischen Modellversuchen werden die Gleitflächen identifiziert, die bei einem “inneren” Versagen des Bodenfüllkörpers eines Fangedamms auftreten. Hieraus wird ein neues Verfahren zum Nachweis der inneren Standsicherheit des Bodenfüllkörpers hergeleitet. Die Vorstellung über die Entwicklung der Gleitflächen und damit auch das Nachweisverfahren weichen von denjenigen der Empfehlungen des Arbeitsausschusses Ufereinfassungen (EAU, 2004 [3]) ab, die vorschreiben, für den Nachweis der inneren Standsicherheit des Bodenfüllkörpers einerseits den Aufbruch des Bodens nach oben und andererseits die Standsicherheit in der tiefen Gleitfuge zu untersuchen. Wird die im Grenzzustand der Tragfähigkeit im Bodenfüllkörper entstehende Gleitflächenschar und das hieraus entwickelte Nachweisverfahren nach Diskussion in den Fachgremien akzeptiert, kann die luftseitige Spundwand eines Fangedamms auf den aktiven Erddruck bemessen werden und muss nicht den nach EAU anzusetzenden 1,25‐fachen aktiven Erddruck aufnehmen. Bei Ansatz eines dem inneren Gleitversagen entsprechenden Teil sicherheitsbeiwerts für den Bodenwiderstand ist die für eine ausreichende innere Standsicherheit des Bodenfüllkörpers erforderliche Breite des Kastenfangedamms nach dem vorgestellten Ansatz in der Regel kleiner als diejenige, die auf der Grundlage des Nachweises der Standsicherheit in der tiefen Gleitfuge gemäß EAU berechnet wird.The inner stability of a coffer dam.Based on the findings from geotechnical model tests, those sliding surfaces are identified, that occur related to the “inner” failure of the soil filling of a coffer dam. Herefrom, a new approach for the verification of the stability of the soil filling is derived. The idea of the development of the sliding surfaces in the ultimate limit state (and therefore also the verification procedure) diverges from the one described in the “Recommendations of the Committee for Waterfront Structures Harbours and Waterways” (EAU, 2004 [3]). If the approach presented in this paper will be accepted after discussion in professional circles, the design of coffer dams could be carried out in a different (and in most cases more cost‐effective) way. For example, the downstream wall of the coffer dam could be designed for active earth pressure (according to the rules of the EAU, the 1,25‐fold active earth pressure has to be used). If the “inner” failure of the soil filling is regarded as a sliding problem (taking in account the respective partial safety factors) the necessary width of cofferdam (to ensure the inner stability of the soil filling) calculated from the approach presented will be smaller compared to the width that is required in compliance with the EAU.
Untersuchungen zur Wiederverwendung von Spundwänden
Authors: Grabe Jürgen , Henke Sascha , Kalle Hans‐Uwe 
Published: May 2009

AbstractInsbesondere in den letzten Jahren wird das Thema Nachhaltigkeit und ressourcenschonender Umgang mit der Umwelt immer stärker in Politik und Gesellschaft diskutiert. Auch in der Geotechnik ist viel Potential vorhanden, nachhaltig mit den Rohstoffen umzugehen. In diesem Beitrag wird hierzu auf die Möglichkeiten der Wiederverwendung von Stahlspundwänden eingegangen. Dabei wird ein wesentliches Augenmerk auf die Möglichkeiten des Recyclings des Spundwandstahls gelegt. Weiterhin erfolgt eine ausführliche Diskussion bezüglich des Ziehens von Spundwänden und den hierbei auftretenden Problemen. So ist häufig ein Anstieg des Herausziehwiderstands über die Zeit feststellbar. Anhand verschiedener Finite‐Elemente‐Untersuchungen wird dieser Zuwachs des Herausziehwiderstands numerisch untersucht, und es können verschiedene Faktoren herausgearbeitet werden, die dem zugrunde liegen.Investigations regarding the re‐use of sheet‐piles.Especially in recent years the topic sustainability and careful handling of environment are discussed more and more in politics and society. In geotechnical engineering there is great potential to deal more sustainable with the used resources. In this contribution, the possibilities of re‐using steel sheet‐piles are discussed. A main scope is set on the possibilities of recycling of the steel. Furthermore, the pull‐out process of sheet‐piles is discussed and problems during the pull‐out process are described. In‐situ often an increase of pull‐out forces over time can be noticed. Several numerical investigations using finite element method are presented to investigate the possible factors which influence the increase in pull‐out forces.
Features of anti‐inflammatory effects of modulated extremely high‐frequency electromagnetic radiation
Authors: Gapeyev Andrew B. , Mikhailik Elena N. , Chemeris Nikolay K. 
Published: May 2009

AbstractUsing a model of acute zymosan‐induced paw edema in NMRI mice, we test the hypothesis that anti‐inflammatory effects of extremely high‐frequency electromagnetic radiation (EHF EMR) can be essentially modified by application of pulse modulation with certain frequencies. It has been revealed that a single exposure of animals to continuous EHF EMR for 20 min reduced the exudative edema of inflamed paw on average by 19% at intensities of 0.1–0.7 mW/cm2 and frequencies from the range of 42.2–42.6 GHz. At fixed effective carrier frequency of 42.2 GHz, the anti‐inflammatory effect of EHF EMR did not depend on modulation frequencies, that is, application of different modulation frequencies from the range of 0.03–100 Hz did not lead to considerable changes in the effect level. On the contrary, at “ineffective” carrier frequencies of 43.0 and 61.22 GHz, the use of modulation frequencies of 0.07–0.1 and 20–30 Hz has allowed us to restore the effect up to a maximal level. The results obtained show the critical dependence of anti‐inflammatory action of low‐intensity EHF EMR on carrier and modulation frequencies. Within the framework of this study, the possibility of changing the level of expected biological effect of modulated EMR by a special selection of combination of carrier and modulation frequencies is confirmed. Bioelectromagnetics 30:454–461, 2009. © 2009 Wiley‐Liss, Inc.
Cellulose hydrolysis in evolving substrate morphologies I: A general modeling formalism
Authors: Zhou Wen , Schüttler Heinz‐Bernd , Hao Zhiqian , Xu Ying 
Published: May 2009

AbstractWe develop a general framework for a realistic rate equation modeling of cellulose hydrolysis using non‐complexed cellulase. Our proposed formalism, for the first time, takes into account explicitly the time evolution of the random substrate morphology resulting from the hydrolytic cellulose chain fragmentation and solubilization. This is achieved by integrating novel geometrical concepts to quantitatively capture the time‐dependent random morphology, together with the enzymatic chain fragmentation, into a coupled morphology‐plus‐kinetics rate equation approach. In addition, an innovative site number representation, based on tracking available numbers of β(1,4) glucosidic bonds, of different “site” types, exposed to attacks by different enzyme types, is presented. This site number representation results in an ordinary differential equation (ODE) system, with a substantially reduced ODE system size, compared to earlier chain fragmentation kinetics approaches. This formalism enables us to quantitatively simulate both the hydrolytically evolving random substrate morphology and the profound, and heretofore neglected, morphology effects on the hydrolysis kinetics. By incorporating the evolving morphology on an equal footing with the hydrolytic chain fragmentation, our formalism provides a framework for the realistic modeling of the entire solubilization process, beyond the short‐time limit and through near‐complete hydrolytic conversion. As part I of two companion papers, the present paper focuses on the development of the general modelling formalism. Results and testable experimental predictions from detailed numerical simulations are presented in part II. Biotechnol. Bioeng. 2009; 104: 261–274 © 2009 Wiley Periodicals, Inc.
Recanalization of chronic occlusions of the superficial femoral artery using the outback™ re‐entry catheter: A single centre experience
Authors: Beschorner Ulrich , Sixt Sebastian , Schwarzwälder Uwe , Rastan Aljoscha , Mayer Christian , Noory Elias , Macharzina Roland , Buergelin Karlheinz , Bonvini Robert , Zeller Thomas 
Published: May 2009

AbstractPurpose: To report our experience with a catheter system (The Outback™ catheter) designed to allow fluoroscopically controlled re‐entry after subintimal guide wire passage during recanalization of chronically occluded femoro‐popliteal arteries. Methods: Between March 2007 and August 2008, 65 legs in 61 patients (60% male, mean age 73 (49–98 years) with chronic occlusion of the SFA and proximal popliteal artery were treated. Clinical presentation was severe intermittent claudication (Rutherford category 3, 59%), rest pain (Rutherford category 4, 16%), and minor ulcerations (Rutherford category 5, 25%). In all cases, the true lumen could not be entered by using standard antegrade catheter and guide wire techniques. Results: Median lesion length was 200 ± 102 mm. Recanalization of the arterial occlusion was successful in 57 of 65 treated lesions (88%). One patient died of myocardial infarction after delayed femoral bleeding possibly due to extensive recanalization attempts. There were no further procedure‐related complications. Conclusion: Use of the Outback™ re‐entry catheter system is a valuable option for interventional therapy of chronically occluded femoro‐popliteal arteries following failed standard antegrade recanalization attempt. © 2009 Wiley‐Liss, Inc.
Acute fracture of ACCULINK carotid stent during post dilation
Authors: Habib Najibullah , van der Heyden Jan 
Published: May 2009

AbstractCarotid angioplasty and stenting has become a valuable alternative treatment for carotid endarterectomy. However, several complications can occur during this high‐risk procedure. We describe a case of carotid stent procedure during carotid angioplasty in a 70‐year‐old man. Management of this complication with an overview of current literature is discussed. © 2009 Wiley‐Liss, Inc.