bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isothermal crystallization and melting behaviors of bionanocomposites from poly(lactic acid) and TiO2 nanowires
Authors: Li Yonghui , Chen Caihong , Li Jun , Sun Xiuzhi Susan 
Published: November 2011

AbstractTwo representative poly(lactic acid) (PLA) nanocomposites with 1% TiO2 nanowires were prepared through in situ melt polycondensation and easy solution‐mixing approaches, respectively. The former was denoted as ISPLANC, and the latter as SMPLANC. The isothermal crystallization kinetics and melting behaviors of pure PLA, ISPLANC, and SMPLANC were comparatively investigated by differential scanning calorimetry in the temperature range of 80–115°C. Maximum crystallization growth rate (Gexp) was observed at 100°C for all three samples. The well dispersed TiO2 nanowires acted as effective nucleation agents in ISPLANC, which exhibited much higher Gexp in compared to pure PLA and SMPLANC below 110°C. However, much smaller crystallization enthalpy of ISPLANC was obtained because of its restricted chain mobility in forming crystalline lamellar. The crystallization behavior of all three samples fit the Avrami equation quite well, with most of the R2 values larger than 0.9990. Double‐melting behaviors were observed after heating the samples after isothermal crystallization at various temperatures, which was explained by the melt recrystallization of the smaller and imperfect crystals formed at lower isothermal crystallization temperatures. We also obtained the equilibrium melting temperatures of the three samples by carrying out Hoffman–Weeks plots. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
The role of dry and wet isothermal annealing treatment on the structure and the mechanical properties of isotactic polypropylene fibers
Authors: Karacan Ismail , Benli Hüseyin 
Published: November 2011

AbstractDry and wet annealing of isotactic polypropylene fibers was carried out under constant length at 120°C in air and in glycerine environments with annealing times ranging from 1 to 30 h. A detailed analysis of the infrared spectrum of samples annealed, especially in air, showed clear evidence of the surface oxidation as indicated by the appearance of oxygen containing functional groups. Annealing was found to lead to an improved structural organization as indicated by the crystallinity, crystallite size, and orientation measurements using X‐ray diffraction and infrared spectroscopy methods. Analysis of the X‐ray diffraction measurements showed a gradual transformation of metastable smectic phase to a more stable α‐monoclinic phase with increasing annealing time. Crystallinity, crystallite size, and orientation measurements performed for the samples annealed in air and in glycerine environments showed no distinct difference. Mechanical properties of the annealed samples were influenced by the annealing environment. Annealing in an air environment resulted in a continuous loss of tensile strength up to the annealing time of 12 h due to an oxidation related chain scission mechanism. On the other hand, annealing in glycerine environment resulted in a continuous and gradual increase of tensile strength without loss of physical form up to the annealing time of 30 h. It is suggested that wet annealing in glycerine environment should be used to obtain improved tensile strength values. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Evaluation of physico‐mechanical properties and in vitro biocompatibility of compression molded HDPE based biocomposites with HA/Al2O3 ceramic fillers and titanate coupling agents
Authors: Tripathi Garima , Dubey Ashutosh Kumar , Basu Bikramjit 
Published: November 2011

AbstractThe present article demonstrates how the stiffness, hardness as well as the cellular response of bioinert high‐density polyethylene (HDPE) can be significantly improved with combined addition of both bioinert and bioactive ceramic fillers. For this purpose, different amounts of hydroxyapatite and alumina, limited to a total of 40 wt %, have been incorporated in HDPE matrix. An important step in composite fabrication was to select appropriate solvent and optimal addition of coupling agent (CA). In case of chemically coupled composites, 2% Titanium IV, 2‐propanolato, tris iso‐octadecanoato‐O was used as a CA. All the hybrid composites, except monolithic HDPE, were fabricated under optimized compression molding condition (140°C, 0.75 h, 10 MPa pressure). The compression molded composites were characterized, using X‐ray diffraction, Fourier transformed infrared spectroscopy, and scanning electron microscopy. Importantly, in vitro cell culture and cell viability study (MTT) using L929 fibroblast and SaOS2 osteoblast‐like cells confirmed good cytocompatibility properties of the developed hybrid composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effects of liquid‐type silane additives and organoclay on the morphology and thermal conductivity of rigid polyisocyanurate‐polyurethane foams
Authors: Kim Youn Hee , Kang Min Jung , Park Gun Pyo , Park Sang Do , Kim Sang Bum , Kim Woo Nyon 
Published: November 2011

AbstractThis article investigates the effects of liquid‐type silane additives and organoclay as a solid‐type additive on the morphological, mechanical and thermal insulating properties of polyisocyanurate‐polyurethane (PIR‐PUR) foams. The organoclay likely acted as nucleating agents during the formation of PIR‐PUR foams. When the liquid silane additives and organoclay were added, the cell size and thermal conductivity of the PIR‐PUR foams appeared to be decreased. However, organoclay did not contribute to reduce the cell size distribution of the foam. PIR‐PUR foams synthesized with tetramethylsilane as a liquid‐type additive showed a smaller average cell size and lower thermal conductivity than that of PIR‐PUR foams synthesized with the other silane additives or with organoclay as a solid‐type additive. For the PIR‐PUR foam with organoclay/TEMS (1.5/1.5 php) mixture, cell size and thermal conductivity of the foam showed similar to the foam with TEMS. These results suggest that smaller cell size appears to be one of the major factors in the improvement of thermal insulation properties of the PIR‐PUR foams. Silane additives did not seem to have a strong effect on the flammability of the PIR‐PUR foams. However, heat resistance was more dominant for the foam with the organoclay at the higher temperature. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effect of adding feldspar on free volume properties of crosslinked polyester studied by positron annihilation lifetime spectroscopy
Authors: Gomaa E. , N. Asaad J. 
Published: November 2011

AbstractPositron annihilation lifetime spectroscopy (PAL) was applied to study the feldspar effect on the free volume properties of crosslinked polyester based on neopentyl glycol, succinic acid, phthalic anhydride, and maleic anhydride. The measurements have been carried on the polyester resin samples cured with three crosslinking agents namely styrene (SS) or styrene/methyl methacrylate (SM) or styrene/acrylonitrile (SA) comonomers mixtures in the ratios of 2 : 1 and loaded with different concentrations of feldspar in the range from 0 to 80 wt %. The free volume parameters (size and fractions of holes) depend on type of the crosslinking agent as well as the feldspar content added to the polyester. The results are supported by a significant variation in the nanoscale free volume hole size distributions. Moreover, the correlation between positron annihilation parameters and electrical parameters was discussed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
A study of factors that affect the information‐seeking behavior of academic scientists
Authors: Niu Xi , Hemminger Bradley M. 
Published: October 2011

AbstractIn an effort to understand how academic scientists seek information relevant to their research in today's environment of ubiquitous electronic access, a correlation framework is built and regression analysis is applied to the survey results from 2,063 academic researchers in natural science, engineering, and medical science at five research universities in the United States. Previous work has reported descriptive statistics about these scientists' information‐seeking behavior. This study extends that work to examine relationships between scientists' information‐seeking behaviors and their personal and environmental factors. Several regression models, including the Poisson model, the logit model, and the ordered logit model, are built to interpret the correlation among scientists' behaviors. In addition, exploratory factor analysis is used for data reduction. Overall, many factors were found to affect the specific information‐seeking behaviors of scientists, including demographic, psychological, role‐related, and environmental factors. Of the factors having an effect, academic position was the most important determinant of information behavior.
Anionic peroxidase production byArnebia euchromacallus
Authors: Farhadi Sahar , Haghbeen Kamahldin , Marefatjo Mohammad‐Javad , Hoor Marjan Ghiyami , Zahiri Hossein Shahbani , Rahimi Karim 
Published: October 2011

AbstractArnebia euchromacallus, obtained from the root cell culture of an Iranian native specimen, has gained a doubling time of 63 H after regular subculturing on Linsmaier–Skoog (LS) medium containing sugar (50 g/L), 2,4‐dichlorophenoxyacetic acid (10−6M), and kinetin (10−5M) under darkness at 25°C. Despite the observed somaclonal variations, peroxidase production by theA. euchromacalli has been stable over 4 years under the aforementioned conditions. Isoelectric focusing experiments revealed that the partially purifiedA. euchromaperoxidases (AePoxs) are mainly anionic with pI values of about 5.5 and 6.6. AePox reaches its optimal activity at 55°C and pH 7.5. Results of the various kinetic studies suggest that AePox belongs to the type III plant peroxidases with no activity for the oxidation of 3‐indoleacetic acid, but seems to play a role in the lignin biosynthesis and H2O2regulation during the proliferation of theA. euchromacells on LS medium. Comparing the biochemical properties of AePox with horseradish peroxidase and in view of the ease of solid cell culture, theA. euchromacallus could be considered as a source of plant peroxidase for some biotechnological applications.
Straßenbrücken zwischen aktuellem und zukünftigem Verkehr – Straßenverkehrslasten nach DIN EN 1991‐2/NA
Authors: Freundt Ursula , Böning Sebastian , Kaschner Rolf 
Published: November 2011

AbstractDie Auswirkungen des aktuellen Schwerverkehrsaufkommens im deutschen Straßennetz und dessen prognostizierte Entwicklung auf die Beanspruchung der Straßenbrücken werden untersucht. Im Schwerpunkt stehen dabei die Einwirkungen auf den Neubau von Brücken. Es werden aber auch Untersuchungen für den Bauwerksbestand vorgestellt. Diese finden in der Nachrechnungsrichtlinie ihren Niederschlag.Road bridges between actual and future heavy load traffic – Road traffic loads according to DIN EN 1991‐2/NAThe effects of the actual heavy load traffic on the Germen road network and the predicted future development of this traffic to the actions on road bridges are analysed. The main focus are the loads for the design of new road bridges. Analyses for the load on existing bridges are given too. Those are part of the guideline for recalculation of bridges.
Wildbrücke Völkermarkt – vorgespanntes Bogentragwerk aus UHFB‐Segmentfertigteilen
Authors: Reichel Michael , Sparowitz Lutz , Freytag Bernhard 
Published: November 2011

AbstractIn unserer wachsenden Infrastruktur werden die Forderungen nach wartungsarmen und langlebigen Bauwerken, die zugleich den Forderungen der Nachhaltigkeit entsprechen, immer größer. Dass Ultrahochfester Beton – nachfolgend UHFB genannt – ein solch hohes Potenzial in Bezug auf seine Festigkeits‐ und Dauerhaftigkeitseigenschaften aufweist, zeigten bereits Forschungsergebnisse vor mehr als 20 Jahren, die aktuelle Untersuchungen inzwischen bestätigen. Berücksichtigt man die enormen Stärken dieses Baustoffes konsequent bei der Umsetzung in einem materialgerechten Entwurf, lassen sich wirtschaftliche, dauerhafte und nachhaltige Bauwerke mit eminentem Nutzen für unsere Volkswirtschaft errichten. Die Fertigteilsegmentbögen des Pilotprojektes Wildbrücke Völkermarkt vereinigen das hohe Potenzial von UHFB mit einer materialgerechten Tragwerksausbildung, mit einem effizienten und schnellen Bauverfahren und einer einfachen und schnellen aber auch robusten und dauerhaften Fügetechnik.Bridge WILD Völkermarkt – prestressed arched structure made of precast UHPC‐segments. Part 1 – Design and detailingOur steadily expanding infrastructure requires long‐lasting buildings which can be maintained with low effort. At the same time they should meet the comprehensive demands of sustainability. Ultra high performance concrete (UHFB) is a building material which is, due to its particular properties, predestined for the application in such buildings. It is strong, tough and durable. Its high potential for application in this field was already recognised twenty years ago. Since then this was confirmed by means of manifold research. It is very important to keep in mind that normal strength concrete cannot simply be replaced by UHFB. It is a new material the properties of which must be considered carefully and consistently when designing structures. This is how the beneficial material properties can be utilised in buildings, which consequently will result in a great economic exploitation. The pilot project WILD‐bridge follows these basic principles. The development of the bridge led to a pre‐cast segmental arch which is slender and therefore very light. Thus, it can quickly be assembled and erected. Not only do the pre‐cast elements meet the demands of sustainability but also the joints. They are realised simple and robust by means of high precision dry joints. Part 1 of the paper deals with form finding, structural detailing and the structural analysis of the WILD‐bridge.
Development and validation of an LC‐MS/MS‐ESI method for the determination of lorglumide, a CCK‐1 antagonist in mouse plasma: application to a pharmacokinetic study
Authors: Sharma Kuldeep , Police Anitha , Kumar Avinash , Pawar Gopal V. , Giri Sanjeev , Rajagopal Sriram , Mullangi Ramesh 
Published: November 2011

ABSTRACTA highly sensitive, rapid assay method was developed and validated for the estimation of lorglumide in mouse plasma using liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in positive‐ion mode. The assay procedure involves extraction of lorglumide and phenacetin (internal standard, IS) from mouse plasma with simple protein precipitation. Chromatographic separation was achieved using an isocratic mobile (0.2% formic acid solution–acetonitrile, 20:80, v/v) at a flow‐rate of 0.5 mL/min on an Atlantis dC18 column maintained at 40 °C with a total run time of 4.0 min. The MS/MS ion transitions monitored were 459.2 → 158.4 for lorglumide and 180.1 → 110.1 for IS. Method validation was performed as per FDA guidelines and the results met the acceptance criteria. The lower limit of quantitation achieved was 0.42 ng/mL and the linearity range extended from 0.42 to 500 ng/mL. The intra‐ and inter‐day precisions were in the ranges of 1.47–10.9 and 3.56–7.53, respectively. Copyright © 2011 John Wiley & Sons, Ltd.
An intelligent tutor for teaching software design patterns
Authors: Berdun Luis , Amandi Analia , Campo Marcelo 
Published: October 2011

ABSTRACTHow to teach students to design in the classroom? When is experience crucial to do design? In particular, how to teach design patterns to students who are beginning to know the importance of a good design? Experience is essential to understand and apply patterns in an effective way. Generally, novice users are not good at working in real experiences while they are good at learning new techniques and methods for designing. In this work, we show the results of teaching patterns using an artificial intelligent assistant that helps novice developers during the design process. Our assistant is an interface agent that observes novice users working, and when it detects that a design pattern can be applied, it makes a suggestion justifying its opinion. Thus, students understand when and where a pattern could be applied.© 2011 Wiley Periodicals, Inc. Comput Appl Eng Educ 22:583–592, 2014; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.20582
Characterization of Optimal Aptamer‐Microarray Binding Chemistry and Spacer Design
Authors: Zhu G. , Lübbecke M. , Walter J.‐G. , Stahl F. , Scheper T. 
Published: November 2011

AbstractCompared to conventional protein microarrays, the aptamer microarray is a relatively new and competitive method for analytical applications. The three‐dimensional folded aptamers show excellent binding specificity and affinity, and thus, can be used as an alternative to antibodies. Immobilization and binding effects of aptamers under different combinations of surfaces and spacers for aptamer‐microarray applications are investigated. In addition, the effects of spacers integrated at the terminal position of aptamers on made in‐house and commercially available microarray supports are explored.
Alkaline Hydrolysis of an Aromatic Ester: Kinetic Studies Using Thermal Power Profiles
Authors: Pečar D. , Goršek A. 
Published: November 2011

AbstractThe reaction kinetics of ethyl benzoate saponification with sodium hydroxide in a heterogeneous reaction medium was investigated. The rate of reaction in a heterogeneous liquid‐liquid system incorporates a chemical kinetics term as well as the mass transfer between both phases. The reaction was carried out in a reaction calorimeter and the overall reaction rate was determined from the obtained thermal profiles. The mass transfer parameters were calculated numerically, taking into account those reaction rate constants determined in our previous study, where the above‐mentioned reaction was conducted in a homogeneous reaction medium. The dependence of the mass transfer parameters and reaction rates on different heterogeneity stages and temperatures is described.
Hydrothermal Carbonization – 1. Influence of Lignin in Lignocelluloses
Authors: Dinjus E. , Kruse A. , Tröger N. 
Published: November 2011

AbstractHydrothermal carbonization is an attractive process for converting biomass with high water content into different products. The requirements on the products, which may be soil improvement or substitution of lignite or carbon black, are opposed to biomass as a feedstock that has a very complex and variable composition. The goal of this work was to study the influence of an ingredient, here lignin, on carbonization, with the focus being not only on the composition but also on the structure of the product formed.
Organometallic Complexes in Supported Ionic‐Liquid Phase (SILP) Catalysts: A PHIP NMR Spectroscopy Study
Authors: Gong Qingxia , Klankermayer Jürgen , Blümich Bernhard 
Published: November 2011

Abstractpara‐Hydrogen induced polarization (PHIP) NMR spectroscopy emerges as an efficient and robust method for on‐line monitoring of gas‐phase hydrogenation reactions. Here we report detailed investigations of supported ionic liquid phase (SILP) catalysts in a continuous gas‐phase hydrogenation of propene with PHIP NMR spectroscopy. A relocation of the rhodium complex in the thin layer of ionic liquid in the SILP catalyst at the initial stage of the propene hydrogenation is demonstrated. PHIP NMR spectroscopy can provide profound insight into the evolution of SILP catalysts during hydrogenation reactions.
Spectroscopic, Morphological, and Mechanistic Investigation of the Solvent‐Promoted Aggregation of Porphyrins Modified in meso‐Positions by Glucosylated Steroids
Authors: Zelenka Karel , Trnka Tomáš , Tišlerová Iva , Monti Donato , Cinti Stefano , Naitana Mario Luigi , Schiaffino Luca , Venanzi Mariano , Laguzzi Giuseppe , Luvidi Loredana , Mancini Giovanna , Nováková Zdena , Šimák Ondřej , Wimmer Zdeněk , Drašar Pavel 
Published: November 2011

AbstractSolvent‐driven aggregation of a series of porphyrin derivatives was studied by UV/Vis and circular dichroism spectroscopy. The porphyrins are characterised by the presence in the meso positions of steroidal moieties further conjugated with glucosyl groups. The presence of these groups makes the investigated macrocycles amphiphilic and soluble in aqueous solvent, namely, dimethyl acetamide/water. Aggregation of the macrocycles is triggered by a change in bulk solvent composition leading to formation of large architectures that express supramolecular chirality, steered by the presence of the stereogenic centres on the periphery of the macrocycles. The aggregation behaviour and chiroptical features of the aggregates are strongly dependent on the number of moieties decorating the periphery of the porphyrin framework. In particular, experimental evidence indicates that the structure of the steroid linker dictates the overall chirality of the supramolecular architectures. Moreover, the porphyrin concentration strongly affects the aggregation mechanism and the CD intensities of the spectra. Notably, AFM investigations reveal strong differences in aggregate morphology that are dependent on the nature of the appended functional groups, and closely in line with the changes in aggregation mechanism. The suprastructures formed at lower concentration show a network of long fibrous structures spanning over tens of micrometres, whereas the aggregates formed at higher concentration have smaller rod‐shaped structures that can be recognised as the result of coalescence of smaller globular structures. The fully steroid substituted derivative forms globular structures over the whole concentration range explored. Finally, a rationale for the aggregation phenomena was given by semiempirical calculations at the PM6 level.