bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of a new conjugated polymer containing dialkoxynaphthalene for efficient polymer solar cells and organic thin film transistors
Authors: Kwon Jun Ho , An Ji‐Young , Jang Hanmae , Choi Solji , Chung Dae Sung , Lee Min‐Jung , Cha Hyo‐Jung , Park Jin‐Hee , Park Chan‐Eon , Kim Yun‐Hi 
Published: January 2011

AbstractA new semiconducting polymer, poly((5,5‐E‐α‐((2‐thienyl)methylene)‐2‐thiopheneacetonitrile)‐alt‐2,6‐[(1,5‐didecyloxy)naphthalene])) (PBTADN), an alternating copolymer of 2,3‐bis‐(thiophene‐2‐yl)‐acrylronitrile and didecyloxy naphthalene, is synthesized and used as an active material for organic thin film transistors (OTFTs) and organic solar cells. The incorporation of 2,3‐bis‐(thiophene‐2‐yl)‐acrylronitrile as an electron deficient group and didecyloxy naphthalene as an electron rich group resulted in a relatively low bandgap, high charge carrier mobility, and finally good photovoltaic performances of PBTADN solar cells. Because of the excellent miscibility of PBTADN and PC71BM, as confirmed by Grazing Incident X‐ray Scattering (GIXS) measurements and Transmission Electron Microscopy (TEM), homogeneous film morphology was achieved. The maximum power conversion efficiency of the PBTADN:PC71BM solar cell reached 2.9% with a Voc of 0.88 V, a short circuit current density (Jsc) of 5.6 mA/cm2, and a fill factor of 59.1%. The solution processed thin film transistor with PBTADN revealed a highest saturation mobility of 0.025 cm2/Vs with an on/off ratio of 104. The molecular weight dependence of the morphology, charge carrier mobility, and finally the photovoltaic performances were also studied and it was found that high molecular weight PBTADN has better self assembly characteristics, showing enhanced performance. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Synthesis and characterization of fluorene‐based oligomers and polymers incorporating N‐arylphenothiazine‐S,S‐dioxide units
Authors: Kamtekar Kiran T. , Dahms Katja , Batsanov Andrei S. , Jankus Vygintas , Vaughan Helen L. , Monkman Andrew P. , Bryce Martin R. 
Published: January 2011

AbstractA series of 3,7‐bis(9,9‐di‐n‐hexylfluoren‐2‐yl)‐N‐arylphenothiazine‐S,S‐dioxide trimers and (9,9‐di‐n‐octylfluorene‐2,7‐diyl‐co‐N‐arylphenothiazine‐S,S‐dioxide) co‐polymers, with varying ratios of phenothiazine‐S,S‐dioxide units, have been prepared in good yields by palladium‐catalyzed cross‐coupling reactions. The materials are deep blue emitters and show no solvatochromism or evidence for an intramolecular charge‐transfer state. The photoluminescence quantum yields of the trimers are ϕPL 15–30% in solution and 14–25% in films. The polymers demonstrated very high values in solution (ϕPL 74–84%) and ϕPL values in films of 28–47%. The estimated HOMO energy levels are between −5.64 and −5.62 eV for the polymers with 15% incorporation of the phenothiazine‐S,S‐dioxide units. An analogous N‐arylphenothiazine co‐polymer shows significantly red shifted absorption and emission. Solution electrochemical data and density functional theory calculations are also presented. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
L‐arabinitol‐based functional polyurethanes
Authors: Ferris Cristina , de Paz M. Violante , Galbis Juan A. 
Published: January 2011

AbstractThree new polymerizable diols, based on mono‐, di‐, and tri‐O‐allyl‐L‐arabinitol derivatives, were prepared from L‐arabinitol as versatile materials for the preparation of tailor‐made polyurethanes with varied degrees of functionalization. Their allyl functional groups can take part in thiol‐ene reactions, to obtain greatly diverse materials. This “click” reaction with 2‐mercaptoethanol was firstly studied on the highly hindered sugar precursor 2,3,4‐tri‐O‐allyl‐1,5‐di‐O‐trityl‐L‐arabinitol, to apply it later to macromolecules. A polyurethane with multiple pendant allyl groups was synthesized by polyaddition reaction of 2,3,4‐tri‐O‐allyl‐L‐arabinitol with 1,6‐hexamethylene diisocyanate, and then functionalized by thiol‐ene reaction. The coupling reaction took place in every allyl group, as confirmed by standard techniques. The thermal stability of the novel polyurethanes was investigated by thermogravimetric analysis and differential scanning calorimetry (DSC). This strategy provides a simple and versatile platform for the design of new materials whose functionality can be easily modified. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Biotin functionalized poly(sulfonic acid)s for bioconjugation: In situ binding monitoring by QCM‐D
Authors: Slavin Stacy , De Cuendias Anne , Ladmiral V. , Haddleton David M. 
Published: January 2011

AbstractWe describe the synthesis of biotin end functionalized poly(sulfonic acid)s via living radical polymerization (LRP) for conjugation to Avidin. Quartz crystal microbalance (QCM‐D) and competitive binding studies were used to confirm this conjugation. A biotin initiator for copper‐mediated LRP was used to provide acrylamide and methacrylate based polymers with the functional end group. This investigation revealed that 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid was not a suitable monomer in its acid form but was successfully used in its sodium salt form. A second monomer, 3‐sulfopropylmethacrylate as the potassium salt was also studied and both monomers produced polymers with polydispersities <1.3 and 1.4, respectively. Evolution of molecular weight with respect to time indicated that the polymerization of the acrylamide polymer is controlled. Quartz crystal microbalance with dissipation monitoring was used to confirm that the biotinylated polymers were able to bind to Avidin in situ. The gold surface of a quartz crystal was chemically modified resulting in a stable monolayer of Avidin; the biotinylated polymers were passed over the functionalized surface and their grafting ability was examined. A competitive binding evaluation was undertaken with 2‐(4‐hydroxyphenylazo)benzoic acid (HABA) dye to provide visual verification of conjugation. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Improving the initiation efficiency in the single electron transfer living radical polymerization of methyl acrylate with electronic chain‐end mimics
Authors: Nguyen Nga H. , Rosen Brad M. , Percec Virgil 
Published: January 2011

AbstractComputational studies on the heterolytic bond dissociation energies and electron affinities of methyl 2‐bromopropionate (MBP) and ethyl 2‐bromoisobutyrate (EBiB) in the dissociative electron transfer (DET) step of single electron transfer living radical polymerization (SET‐LRP) of methyl acrylate (MA) combined with kinetic experiments were performed in an effort to design the most efficient initiation system. This study suggests that EBiB is more effective than MBP in the SET‐LRP of acrylates catalyzed by Cu(0) wire, thus being a true electronic mimic of the dormant PMA species. EBiB allows for a more predictable dependence of the molecular weight evolution and distribution. This is exemplified by the absence of a deviation in the PMA molecular weight from theoretical values at low conversions, as a result of a faster SET activation with EBiB than with MBP. The enhanced control over molecular weight evolution was also observed in the SET‐LRP of MA initiated with bifunctional initiators similar in structure to MBP and EBiB, suggesting a higher reactivity than MBP in the SET activation, which matches closely that of the polymer dormant chains. The use of bifunctional initiators in conjunction with activated Cu(0) wire in SET‐LRP allows for dramatically accelerated polymerizations, although still providing for exceptional control of the molecular weight evolution and distribution. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Atomistic modeling of peptides bound to a chemically active surface: conformational implications
Authors: Curcó David , Revilla‐López Guillem , Alemán Carlos , Zanuy David 
Published: January 2011

AbstractThis work presents a computational strategy to model flexible molecules tethered to a metallic rigid surface. The method is based on a previously developed procedure for inert surfaces, in which peptide–surface interactions were not considered. This procedure is able to generate uncorrelated relaxed microstructures at the atomistic level of systems containing relatively high densities of peptides tethered to the surface. The reliability of the strategy has been tested by simulating CREKA (Cys‐Arg‐Glu‐Lys‐Ala), a short linear pentapeptide that recognizes clotted plasma proteins and selectively homes to tumors, covalently tethered to a gold surface, results being compared with those obtained when the surface was represented as inert. The results indicate that the whole conformational profile of CREKA presents some correlation with the chemical activity of the surface, even though the bioactive conformation was found as the most favored in all cases. Specifically, simulations reflect that consideration of the peptide‐surface interactions affect the geometrical orientation of the side chains, whereas the main chain conformation does not undergo significant modifications. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
Impact of fixed charges at interfaces on the operation of top‐gate carbon nanotube field‐effect transistors
Authors: Ohno Yutaka , Moriyama Naoki , Kishimoto Shigeru , Mizutani Takashi 
Published: January 2011

AbstractTo control the properties of carbon nanotube field‐effect transistors (CNFETs), it is important to understand the properties of various interfaces in the devices and their effects on device characteristics. Here, we studied the influence of interface fixed charges introduced between the gate insulator and the substrate on the operation of a top‐gate CNFET, using device simulation. The simulation results suggest that with the existence of interface charges, the current modulation mechanism of the CNFET changes from Schottky barrier modulation to channel potential modulation. The minority carrier injection in the OFF state is suppressed by the high‐potential region formed near the contact electrodes by the interface charges. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Anomalous reflection properties in high density limit fibril shaped PIC‐J aggregates in microcavity structure
Authors: Obara Yuki , Saitoh Keita , Oda Masaru , Tani Toshiro 
Published: January 2011

AbstractWe report our recent observations on anomalous reflection properties of organic microcavity containing PIC J‐aggregates in fibril‐shaped structures as one of their highest‐density limiting case. Even in ordinary low density PIC‐Js dispersed in polymer matrices, they easily go into the exciton‐photon strong coupling regime and new quantum states, i.e. exciton‐polaritons, are formed. Vacuum Rabi‐splitting, an indicator of the coupling strength, can be controlled by the density of PIC‐Js in the microcavities in low density regime. Fibril‐shaped PIC‐J aggregates are bundle‐like, self‐assembled higher‐order structure of Js and are considered as a high‐density limiting case. Angular dependence of the local reflection spectra are observed by our improved microscopy. While in the low density cases, clear anti‐crossing behaviours of the two branches appear, which is the evidence of the polariton formations, the highest‐density limiting cases show one or two anomalous reflection dip structures with almost no angular dependence. The result is inconsistent with neither ordinary polariton reflection property nor bare exciton nor cavity photon properties. We tentatively consider that the anomaly is inherent to the fibril formation and is caused by possible breakdown of polariton coherence due to the inter‐fiber energy transfer. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modeling data with structural and temporal correlation using lower level and higher level multilevel models
Authors: James Gareth , Zhou Yinghui , Miller Sam 
Published: January 2011

AbstractNovel imaging techniques are playing an increasingly important role in drug development, providing insight into the mechanism of action of new chemical entities. The data sets obtained by these methods can be large with complex inter‐relationships, but the most appropriate statistical analysis for handling this data is often uncertain – precisely because of the exploratory nature of the way the data are collected. We present an example from a clinical trial using magnetic resonance imaging to assess changes in atherosclerotic plaques following treatment with a tool compound with established clinical benefit. We compared two specific approaches to handle the correlations due to physical location and repeated measurements: two‐level and four‐level multilevel models. The two methods identified similar structural variables, but higher level multilevel models had the advantage of explaining a greater proportion of variation, and the modeling assumptions appeared to be better satisfied. Copyright © 2010 John Wiley & Sons, Ltd.
Geographic distance and corporate acquisitions: signals from IPO firms
Authors: Ragozzino Roberto , Reuer Jeffrey J. 
Published: January 2011

AbstractThis paper examines acquisitions of firms after they have undergone initial public offerings (IPOs). Combining insights from information economics with recent research on geographic distance in various market settings, the analysis investigates whether the presence or absence of different signals on IPO firms has an impact on the geographic proximity of acquirers. The central proposition we develop and test is that specific characteristics of IPOs—venture capitalist backing, investment bank reputation, and underpricing of issued shares—convey signals on these firms, which can facilitate acquisitions by more remote acquirers who are more likely to face the risk of adverse selection. Copyright © 2011 John Wiley & Sons, Ltd.
A New Approach to Solution‐Phase Gold Seeding for SERS Substrates
Authors: Tabakman Scott M. , Chen Zhuo , Casalongue Hernan Sanchez , Wang Hailiang , Dai Hongjie 
Published: January 2011

AbstractSurface‐enhanced Raman scattering (SERS) vastly improves signal‐to‐noise ratios as compared to traditional Raman scattering, making sensitive assays based upon Raman scattering a reality. However, preparation of highly stable SERS‐active gold substrates requires complicated and expensive methodologies and instrumentation. Here, a general and completely solution‐phase, seed‐based approach is introduced, which is capable of producing gold films for SERS applications on a variety of substrates, not requiring surface modification or functionalization. SERS enhancement factors of ≈107 were observed. Moreover, solution‐phase gold film deposition on highly complex surfaces, such as protein‐coated bioassays, is demonstrated for the first time. Protein bioassays coated with such SERS‐active gold films are combined with bioconjugated single‐walled carbon nanotube Raman labels, affording highly sensitive detection of the cancer biomarker, carcinoembryonic antigen in serum, with a limit of detection of ≈5 fM (1 pg mL−1).
Zum Last‐Verformungsverhalten von Schrauben in vorgespannten Ringflanschverbindungen mit überbrückten Klaffungen im Hinblick auf die Ermüdungsvorhersage
Authors: Feldmann Markus , Naumes Johannes , Pak Daniel 
Published: January 2011

AbstractIm Rahmen des europäischen RFCS (Research Fund for Coal and Steel) Projektes HISTWIN werden seit 2005 Untersuchungen an konventionellen Ringflanschen im Hinblick auf die Ermüdungssicherheit der Verbindungsmittel durchgeführt. Hauptaugenmerk liegt hierbei auf der Prüfung von Methoden zur Instandsetzung von Flanschimperfektionen und den daraus resultierenden Klaffungen. Werden diese nicht ausgebessert sondern lediglich “beigezogen”, so führt dies zu erhöhten Ermüdungsbelastungen und einem vorzeitigen Versagen des Verbindungsmittels. Deswegen werden hier wesentlich zuverlässigere Alternativen der Überbrückung von Flanschklaffungen mit Hilfe von Futterblechen und expliziten Vorspannabfolgen vorgeschlagen. Zum Nachweis der Wirksamkeit dieser einfachen Reparaturmethoden wurden Versuche durchgeführt und ausgewertet, welche den Schluss zulassen, dass bei sachgemäßer Reparatur der Flanschklaffungen mit keiner reduzierten Lebensdauer der Verbindungsmittel zu rechnen ist.Load‐deformation behaviour of preloaded bolts in ring flange connections with bridged gaps with regard to a fatigue behaviour prediction. Within the scope of the European research project RFCS (Research Fund for Coal and Steel) HISTWIN, conventional ring flange connections have been studied focusing on the fatigue resistance these connections. Often these ring flange connections provide certain imperfections like gaps etc. unless they are machined. Without repairing these gaps result in an increased fatigue loading of the bolt and an early failure of the connection. Therefore reliable alternatives for retrofitting these gaps by means of lining plates are proposed for which two methods have been studied. Furthermore large scale tests have been performed at ring flange connections to prove the effectiveness of the proposed retrofitting methods. It could be found that repairing of the gap‐imperfection as proposed in the paper leads to an unreduced fatigue life of the bolts.
Das Kuppelmodell des Münchener Hauptbahnhofes geprüft von der Materialprüfungsanstalt Stuttgart
Authors: Reiss Hanna 
Published: January 2011

AbstractZur Zeit des Nationalsozialismus wurden viele Städte umgebaut und gigantische Gebäude geplant. Viele NS‐Großbauprojekte sind heute noch bekannt. Unbekannt hingegen sind die unzähligen Bauprojekte die nie realisiert wurden. Der geplante Hauptbahnhof der “Hauptstadt der Bewegung München” ist nur eines der vielen nicht realisierten Projekte. Ihm ging eine sorgfältige Planung und Dokumentation voraus. Das Universitätsarchiv Stuttgart ist im Besitz von Akten der Materialprüfungsanstalt (MPA) Stuttgart, unter denen sich auch die Akten für ein statisches Modell des geplanten Münchner Hauptbahnhofes befinden.The dome model of the Munich Main Station checked through the Materialprüfansalt Stuttgart, Germany. At the time of the National Socialism would many cities new constructed and giant buildings were planned. Many of the NS‐projects are still known today. But unknown are the reams of building projects which never would realized. The planned main station for the “Capital of movement Munich” is only one of many unrealized projects. A careful planning and documentation preceded it. The archive of the University Stuttgart is in the possession of documents of the Materialprüfanstalt (MPA; material control institution) of Stuttgart. Under those also are the documents for a static model of the planned Munich Main Station.
Bauwerk‐Boden‐Interaktion bei lagenweise hinterfüllten Stahlwellblechdurchlässen
Authors: Pittino Gerhard 
Published: January 2011

AbstractVorgeformte Stahlwellblechplatten werden vor Ort zu Rohren, Bögen oder Stahlwellblechdurchlässen zusammengebaut. Für die Tragfähigkeit der flexiblen, erdverlegten Stahlrohre ist die seitliche Bettung durch die Hinterfüllung mit Bodenmaterial ausschlaggebend. Während dem Hinterfüllen entwickelt sich der Erddruck, der zuerst alleine durch den kleinen Biegewiderstand des Rohres getragen werden muss. Die Biegemomentverteilung bleibt nach dem Verfüllen bis zum Rohrscheitel nahezu “eingefroren”. Der vorliegende Beitrag behandelt die Bauwerk‐Boden‐Interaktion anhand von numerischen Berechnungen mit dem Ziel, den Hinterfüllvorgang so zu gestalten, dass die Biegemomente klein bleiben.Soil‐structure interaction of structural plate steel underpasses backfilled in layers. Curved corrugated steel plates are field assembled into pipes, arches, underpasses and other shapes. The lateral bedding that is responsible for the load bearing capacity of the flexible, earth embedded steel pipe is provided only by way of backfilling with soil material. The earth pressure that develops by backfilling must be solely born at first by the small bending resistance of the pipe. The bending moments remain nearly “frozen” after backfilling up to the top. This paper deals with the soil‐structure interaction. This is shown by means of numerical calculations with FLAC as to how the steel conduit should be backfilled so that the bending moments remain small.
The new Guillemins station – a railway station for high‐speed trains
Authors: Crémer Jean‐Marie , de Ville de Goyet Vincent , Counasse Clément , Duchêne Yves , Fagnoul Véronique 
Published: January 2011

AbstractIn Liège, the existing railway infrastructure was not capable of being properly used by high‐speed trains. A number of elements handicapped the site of the old station: curved platforms that were too narrow, an approach speed to the station that was too low, numerous track intersections and poor positioning of the Brussels‐Germany line, even though it carries the most traffic. In comparison with the old building, the route through the new station has been moved 150 m in order to meet two requirements:– to enable straight platforms which make it easier for trains to enter and leave the station and for passengers to embark and disembark;– to establish a harmonious link between the station and the nearby motorway network.This link with the motorway network is provided by a bridge and a viaduct, designed by Santiago Calatrava. This Hillside entrance to the station has the advantage of the availability of a car park with 600 parking spaces, immediately next to the platforms. The station now has nine tracks and five platforms 8 m wide, thus allowing people to move around more freely. Three of the platforms, 450 m long, can accommodate double‐unit HSR units.