bluuebunny/crossref_metadata_2025_split huggingface dataset:
Supramolecular thermoplastic elastomer with thermally scratch repairable effect from 3‐amino‐1,2,4‐triazole crosslinked maleated polyethylene‐octene elastomer/nylon 12 blends
Authors: Kashif Muhammad , Chang Young‐Wook 
Published: October 2014

ABSTRACTIn this study, nylon 12 (5–25 wt %) was melt blended with a supramolecular thermally repairable thermoplastic elastomer (ATA‐POE), which was generated by crosslinking of maleated polyethylene‐octene elastomer (mPOE) with 3‐amino‐1,2,4‐triazole (ATA), in an internal mixer. The effect of nylon 12 content on the phase morphology, thermomechanical properties, and thermally triggered scratch repairing effects of the ATA‐POE/nylon 12 blends was investigated. Scanning electron microscopy results showed that nylon 12 formed a dispersed phase with submicron scale in a continuous ATA‐POE phase. Fourier transform infrared spectroscopy and differential scanning calorimetry analysis revealed that there are extensive hydrogen bonding interactions between the ATA‐POE and nylon 12 in the blends, which was manifested by a decrease in the melting temperature of each polymer component. Tensile and dynamic mechanical test showed that tensile modulus increased with increasing nylon 12 contents in the blend with maintaining fairly high elastic recoverability. Furthermore, the blends containing up to 20 wt % of nylon 12 showed good scratch repairing effects when they are heated above melting temperature of the ATA‐POE phase in the blend. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41511.
On the Importance of Thermal Effects and Crystalline Disorder in the Magnetism of Benzotriazinyl‐Derived Organic Radicals
Authors: Fumanal Maria , Vela Sergi , Ribas‐Ariño Jordi , Novoa Juan J. 
Published: October 2014

AbstractRecent experiments suggest that benzotriazinyl‐derived radicals are promising building blocks for the design of new functional materials. Herein, a detailed computational study of the main structural and magnetic features of two prototypes of this family of radicals is presented. By means of several computational techniques within the DFT framework, this work unveils the key importance of the thermal contraction of the crystal to quantitatively predict the magnetism of the studied compounds. In this sense, for the first time in the context of molecular magnetism, we propose to use variable‐cell geometry optimizations as an efficient alternative to obtain an estimation of low‐temperature crystal structures. The crucial role of crystalline disorder in defining the structure present at low temperature, and thus, the magnetic response, is revealed. Altogether, these are important elements for the rational design of future materials of this family of compounds.
Single‐Molecule Imaging Reveals that Small Amyloid‐β1–42 Oligomers Interact with the Cellular Prion Protein (PrPC)
Authors: Ganzinger Kristina A. , Narayan Priyanka , Qamar Seema S. , Weimann Laura , Ranasinghe Rohan T. , Aguzzi Adriano , Dobson Christopher M. , McColl James , St. George‐Hyslop Peter , Klenerman David 
Published: October 2014

AbstractOligomers of the amyloid‐β peptide (Aβ) play a central role in the pathogenesis of Alzheimer’s disease and have been suggested to induce neurotoxicity by binding to a plethora of cell‐surface receptors. However, the heterogeneous mixtures of oligomers of varying sizes and conformations formed by Aβ42 have obscured the nature of the oligomeric species that bind to a given receptor. Here, we have used single‐molecule imaging to characterize Aβ42 oligomers (oAβ42) and to confirm the controversial interaction of oAβ42 with the cellular prion protein (PrPC) on live neuronal cells. Our results show that, at nanomolar concentrations, oAβ42 interacts with PrPC and that the species bound to PrPC are predominantly small oligomers (dimers and trimers). Single‐molecule biophysical studies can thus aid in deciphering the mechanisms that underlie receptor‐mediated oAβ‐induced neurotoxicity, and ultimately facilitate the discovery of novel inhibitors of these pathways.
A Zinc Phthalocyanine Based Periodic Mesoporous Organosilica Exhibiting Charge Transfer to Fullerenes
Authors: Auras Florian , Li Yan , Löbermann Florian , Döblinger Markus , Schuster Jörg , Peter Laurence M. , Trauner Dirk , Bein Thomas 
Published: October 2014

AbstractPeriodic mesoporous organosilica (PMO) materials offer a strategy to position molecular semiconductors within a highly defined, porous network. We developed thin films of a new semiconducting zinc phthalocyanine‐bridged PMO exhibiting a face‐centered orthorhombic pore structure with an average pore diameter of 11 nm. The exceptional degree of order achieved with this PMO enabled us to create thin films consisting of a single porous domain throughout their entire thickness, thus providing maximal accessibility for subsequent incorporation of a complementary phase. The phthalocyanine building blocks inside the pore walls were found to be well‐aggregated, enabling electronic conductivity and extending the light‐harvesting capabilities to the near IR region. Ordered 3D heterojunctions capable of promoting photo‐induced charge transfer were constructed by impregnation of the PMO with a fullerene derivative. When integrated into a photovoltaic device, the infiltrated PMO is capable of producing a high open‐circuit voltage and a considerable photocurrent, which represents a significant step towards potential applications of PMOs in optoelectronics.
Revised Role of Selectfluor in Homogeneous Au‐Catalyzed Oxidative CO Bond Formations
Authors: Geng Cuihuan , Zhu Rongxiu , Li Mingxia , Lu Tongxiang , Wheeler Steven E. , Liu Chengbu 
Published: October 2014

AbstractThe pairing of transition metal catalysis with the reagent Selectfluor (F‐TEDA–BF4) has attracted considerable attention due to its utility in myriad CC and Cheteroatom bond‐forming reactions. However, little mechanistic information is available for Selectfluor‐mediated transition metal‐catalyzed reactions and controversy surrounds the precise role of Selectfluor in these processes. We present herein a systematic investigation of homogeneous Au‐catalyzed oxidative CO bond‐forming reactions using density functional theory calculations. Currently, Selectfluor is thought to serve as an external oxidant in AuI/AuIII catalysis. However, our investigations suggest that these reactions follow a newly proposed mechanism in which Selectfluor functions as an electrophilic fluorinating reagent involved in a fluorination/defluorination cycle. We have also explored Selectfluor‐mediated gold‐catalyzed homocoupling reactions, which, when cyclopropyl propargylbenzoate is used as a substrate, lead to an unexpected byproduct.
A Metal–Organic Framework Containing Unusual Eight‐Connected Zr–Oxo Secondary Building Units and Orthogonal Carboxylic Acids for Ultra‐sensitive Metal Detection
Authors: Carboni Michaël , Lin Zekai , Abney Carter W. , Zhang Teng , Lin Wenbin 
Published: October 2014

AbstractTwo metal–organic frameworks (MOFs) with Zr–oxo secondary building units (SBUs) were prepared by using p,p′‐terphenyldicarboxylate (TPDC) bridging ligands pre‐functionalized with orthogonal succinic acid (MOF‐1) and maleic acid groups (MOF‐2). Single‐crystal X‐ray structure analysis of MOF‐1 provides the first direct evidence for eight‐connected SBUs in UiO‐type MOFs. In contrast, MOF‐2 contains twelve‐connected SBUs as seen in the traditional UiO MOF topology. These structural assignments were confirmed by extended X‐ray absorption fine structure (EXAFS) analysis. The highly porous MOF‐1 is an excellent fluorescence sensor for metal ions with the detection limit of <0.5 ppb for Mn2+and three to four orders of magnitude greater sensitivity for metal ions than previously reported luminescent MOFs.
Enantiomeric Separations of Ruthenium (II) Polypyridyl Complexes Using HPLC With Cyclofructan Chiral Stationary Phases
Authors: Shu Yang , Breitbach Zachary S. , Dissanayake Milan K. , Perera Sirantha , Aslan Joseph M. , Alatrash Nagham , MacDonnell Frederick M. , Armstrong Daniel W. 
Published: October 2014

AbstractThe enantiomeric separation of 21 ruthenium (II) polypyridyl complexes was achieved with a novel class of cyclofructan‐based chiral stationary phases (CSPs) in the polar organic mode. Aromatic derivatives on the chiral selectors proved to be essential for enantioselectivity. The R‐napthylethyl carbamate functionalized cyclofructan 6 (LARIHC CF6‐RN) column proved to be the most effective overall, while the dimethylphenyl carbamate cyclofructan 7 (LARIHC CF7‐DMP) showed complementary selectivity. A combination of acid and base additives was necessary for optimal separations. The retention factor vs. acetonitrile/methanol ratio plot showed a U‐shaped retention curve, indicating that different interactions take place at different polar organic solvent compositions. The separation results indicated that π–π interactions, steric effects, and hydrogen bonding contribute to the enantiomeric separation of ruthenium (II) polypyridyl complexes with cyclofructan chiral stationary phases in the polar organic mode. Chirality 27:64–70, 2015. © 2014 Wiley Periodicals, Inc.
Das Erdölzeitalter
Authors: Offermanns Heribert , Salesch Martin 
Published: October 2014

AbstractErdöl – vor 100 bis 400 Millionen Jahren aus abgestorbenen Meeresorganismen entstanden – wurde schon seit mehr als 5000 Jahren von den Hochkulturen des Vorderen Orients als Schmierstoff und Bindemittel, zu Heilzwecken, zur Einbalsamierung, Kalfaldern von Booten und zu Kriegszwecken verwendet. Die industrielle Nutzung als Lampenbrennstoff wurde durch die von einigen Pionieren gefundene Methode der Destillation möglich. Nach den ersten erfolgreichen Erdölbohrungen in Wietze (1858) und Titusville (1859) setzte ein Boom ein, der auch nicht gebrochen wurde als Edison die Glühbirne erfand, da der Benzinkarren konstruiert worden war. Die rasch einsetzende Motorisierung läutete das Erdölzeitalter ein. Erdöl gewann auch an Bedeutung als Energierohstoff und ist der wichtigste Chemierohstoff. Die Vorräte an fossilen Rohstoffen sind endlich und Erdöl wird noch im diesem Jahrhundert weitgehend erschöpft sein. Es bedarf enormer Anstrengungen, Energie‐ und Chemierohstoffe “Beyond Oil” bereitzustellen und den Forderungen nach Versorgungssicherheit, Bezahlbarkeit und Umweltschonung gerecht zu werden.
Joseph Beuys und die Braunkreuzfarbe
Authors: Valler Ole , Nast Krzysztof , Strieder Barbara , Scholz Peter 
Published: October 2014

AbstractPhysikalisch‐chemische Analysetechniken, allen voran die zerstörungsfreie Röntgenfluoreszenzanalytik (RFA) vor Ort im Museum, geben Einblick in Materialeinsatz und Schaffensprozesse des Künstlers Joseph Beuys. Recherchearbeit, die Befragung von Zeitzeugen und andere Herangehensweisen kennzeichnen die interdisziplinären Anforderungen und den Reiz, den moderne kunsthistorische Arbeit ausmacht; die chemische Analytik liefert einen Beitrag. Ein analytisches Instrument, mit dem die bislang wenig systematische Zuordnung in die Werkgruppe der Braunkreuz‐Arbeiten nunmehr erfolgen kann, wird vorgeschlagen: die Pigmentanalyse mittels RFA.
Dehydrierung: Die Angst geht um
Authors: Roth Klaus 
Published: October 2014

AbstractWasser ist gesund, ja lebenswichtig, aber auch giftig. In unserem Körper sorgt ein ausgeklügeltes biochemisches Regelungssystem für die tägliche Aufnahme der optimalen Wassermenge. Wir müssen nicht befürchten, unter normalen Umständen dehydratisiert zu werden, wenn wir trinken, wenn wir “durstig” sind und aufhören, wenn wir “nicht durstig” [51] sind. Nur wenn wir entgegen unserem Körpergefühl exorbitant viel Wasser trinken, begeben wir uns in Gefahr. Wohl dem, der sich einige Chemiekenntnisse gepaart mit gesundem Menschenverstand und ein wenig kritischer Distanz gegenüber dem vielstimmigen, aber unqualifiziertem Zeitgeist und Modediäten bewahrt hat.
Mehrfach ungesättigte Fettsäuren als Nervennahrung
Authors: Hille‐Rehfeld Annette 
Published: October 2014

AbstractAn den Synapsen von Nervenzellen muss nach der Freisetzung von Neurotransmittern aus Speichervesikeln das Gleichgewicht der Membranen durch Endocytose wiederhergestellt werden. Die Bildung der Endocytosevesikel wird durch Lipide mit mehrfach ungesättigten Fettsäuren gefördert, die Fehlstellen in der gekrümmten Lipiddoppelschicht minimieren und so die Flexibilität der Membranen erhöhen.
Chemie, die uns guttut
Authors: Harrer Roswitha 
Published: October 2014

AbstractHart, Zement, Beton: In der Antike noch sehr erfolgreich, war das “opus caementicium” über 1000 Jahre in Vergessenheit geraten. Erst im frühen 19. Jahrhundert begann man wieder mit Zement und Beton zu bauen – heute ist kein Stadtbild mehr ohne die hydratisierten Minerale vorstellbar. Aber auch in der Zahnmedizin sind mineralische Härtungsreaktionen nützlich. Die Chemie des Zements tut gut.
Analysis of heat transfer in a vessel with helical pipe coil and multistage impeller
Authors: Dostál Martin , Věříšová Marcela , Petera Karel , Jirout Tomáš , Fořt Ivan 
Published: October 2014

AbstractResults of heat transfer coefficient measurements in an agitated vessel heated or cooled by the liquid media flowing in a helical pipe coil are presented in this paper. The multistage impeller made of two pitched six‐blade impellers and adjustable clearance was used in a vessel with conical bottom. The transient method based on measuring the temperature dependency on time and solving the unsteady enthalpy balance was used to determine the heat transfer coefficients between the agitated liquid and the helical pipe coil. The results are summarized by the Nusselt number correlations, which describe the dependency on the impeller Reynolds number. The second part of this paper introduces a theoretical analysis of the flow in the liquid batch near the helical pipe coil. Based on the known pumping capacity of the multistage impeller, the characteristic velocity near the helical pipe coil can be evaluated. This characteristic velocity can be then used to determine the Nusselt number describing the heat transfer in a flow around a cylinder with the same cross‐section profile as the helical pipe coil. A clear correlation between this Nusselt number and the integral Nusselt number is presented in this paper and introduces an alternative approach for prediction of heat transfer characteristics on the basis of hydrodynamic parameters describing an agitated system.
P2Pedia: a peer‐to‐peer wiki for decentralized collaboration
Authors: Davoust Alan , Craig Alexander , Esfandiari Babak , Kazmierski Vincent 
Published: October 2014

SummaryExisting Wiki systems such as Wikipedia depend on a centralized authority and cannot easily accommodate multiple points of view. We present P2Pedia, a social peer‐to‐peer wiki system, where users have their own local repository and can collaborate by creating, discovering, editing, and sharing pages with their peers but without synchronizing them. Multiple versions of each page can thus co‐exist on each repository and across the network, which allows for multiple points of view.Browsing or searching the wiki thus yields multiple page versions; to help the user's page selection process, the system annotates search results with trust indicators based on the distribution of each version in the peer repositories and the topology of the social network.We describe an experimental study where the system was deployed for academic writing exercises, and we analyze the results to validate different aspects of this collaboration principle. Copyright © 2014 John Wiley & Sons, Ltd.
Light‐Induced Self‐Assembly and Decay of J Aggregates of Thiamonomethinecyanine Dyes
Authors: Petrenko Volodymyr Yu. , Dimitriev Oleg P. 
Published: October 2014

AbstractFormation of J aggregates, that is, one‐dimensional supramolecular self‐organizations in which the transition moments of individual molecules are aligned parallel to the line joining their centers through a “head‐to‐tail” arrangement, normally proceed via electrostatic interactions between oppositely charged molecular groups; this is facilitated by an electrolyte medium. Here, we show that J aggregates of thiamonomethinecyanine dyes in a solution can be assembled from dye dimers by illuminating the solution with light of the appropriate wavelength to induce excitation of the dye dimers. The reverse process is also demonstrated by application of light of the correct wavelength to induce excitation of the J aggregates. Our results indicate that spontaneous J aggregation in the dark and formation of J aggregates through illumination proceed through different mechanisms; the former resulting in an increase in the number of the aggregates and the latter in an increase in the size of the aggregates.
Improving the Field‐Effect Performance of Bi2S3 Single Nanowires by an Asymmetric Device Fabrication
Authors: Lu Fangyuan , Li Renxiong , Li Yan , Huo Nengjie , Yang Juehan , Li Yongtao , Li Bo , Yang Shengxue , Wei Zhongming , Li Jingbo 
Published: October 2014

AbstractHigh‐quality Bi2S3 nanowires are synthesized by chemical vapor deposition and their intrinsic photoresponsive and field‐effect characteristics are explored in detail. Among the studied Au–Au, Ag–Ag, and Au–Ag electrode pairs, the device with stepwise band alignment of asymmetric Au–Ag electrodes has the highest mobility. Furthermore, it is shown that light can cause a sevenfold decrease of the on/off ratio. This can be explained by the photoexcited charge carriers that are more beneficial to the increase of Ioff than Ion. The photoresponsive properties of the asymmetric Au–Ag electrode devices were also explored, and the results show a photoconductive gain of seven with a rise time of 2.9 s and a decay time of 1.6 s.
Ordered Hierarchically Porous Carbon Codoped with Iron and Nitrogen as Electrocatalyst for the Oxygen Reduction Reaction
Authors: Deng Chengwei , Zhong Hexiang , Yao Lan , Liu Sisi , Xu Zhuang , Zhang Huamin 
Published: October 2014

AbstractN‐doped carbon catalysts have attracted great attention as potential alternatives to expensive Pt‐based catalysts used in fuel cells. Herein, an ordered hierarchically porous carbon codoped with N and Fe (Fe‐NOHPC) is prepared by an evaporation‐induced self‐assembly process followed by carbonization under ammonia. The soft template and Fe species promote the formation of the porous structure and facilitate the oxygen reduction reaction (ORR).The catalyst possesses an ordered hierarchically porous structure with a large surface area (1172.5 m2 g−1) and pore volume of 1.03 cm3 g−1. Compared to commercial 20 % Pt/C, it exhibits better ORR catalytic activity and higher stability as well as higher methanol tolerance in an alkaline electrolyte, which demonstrates its potential use in fuel cells as a nonprecious cathode catalyst. The N configuration, Fe species, and pore structure of the catalysts are believed to correlate with its high catalytic activity.
Comparative study of the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours as affected by pH
Authors: Raikos Vassilios , Neacsu Madalina , Russell Wendy , Duthie Garry 
Published: October 2014

AbstractThe demand for products of high nutritional value from sustainable sources is growing rapidly in the global food market. In this study, the effect of pH on the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours was investigated and compared with wheat flour. Functional properties included solubility, emulsifying and foaming properties, gelling ability, and water holding capacity (WHC). All flours had minimal solubility at pH 4 and their corresponding values increased with increasing pH. Emulsifying properties were improved at pH 10 for all samples and emulsion stability showed a similar trend. Increasing pH in the range 4–10 enhanced the foaming properties of the flours, particularly buckwheat and hemp. Wheat, green pea, buckwheat, and fava bean were more capable of forming firm gels compared with lupin and hemp, as indicated by least gelling concentrations (LGCs). The ranking of the water binding properties of the different types of flours were lupin>hemp>fava bean>buckwheat>green pea>wheat. Results indicate that underutilized flours from sustainable plant sources could be exploited by the food industry as functional food ingredients or as replacements of wheat flour for various food applications. Depending on the application, flour functionality may be effectively tailored by pH adjustment.
The Ghosts of Institutionalization at Pennhurst's Haunted Asylum
Authors: BEITIKS EMILY SMITH 
Published: October 2014

AbstractIn the woods of Spring City, Pennsylvania, lies Pennhurst, a school for people with developmental and physical disabilities from 1908 to 1987. Like many institutions, Pennhurst eventually became a place of abuse and neglect. Pennhurst was finally shut down, and the residents were relocated into group homes. Two years ago, a group well educated about Pennhurst's past formed the Pennhurst Memorial and Preservation Alliance, a nonprofit dedicated to making Pennhurst into a national museum. Standing in the way of PM&PA's vision was a businessman named Richard Chakejian, who purchased Pennhurst from the state for $2 million and has now converted it to a haunted house. The result is a bizarre hybrid of history and legend, and of criminality and commercialism, that simultaneously evokes and erases Pennhurst's troubled past.
Using Monkeys to Understand and Cure Parkinson Disease
Authors: Redmond, Jr. D. Eugene 
Published: October 2014

AbstractResearch with nonhuman primates is essential to medical progress and will still be necessary for the foreseeable future. Almost all research scientists agree that animal research is critical to understanding basic biology, discovering new treatments for human (and animal) diseases, and maximizing the safety of new medicines while minimizing their harm to humans. All but two of the Nobel prizes in medicine awarded over the last one hundred years have depended on animal research, and the list of modern medicines, vaccines, and other treatments, as well as basic science discoveries, is so extensive that it could not be adequately covered in even a huge volume. Increases in average life span in the last century are the result of improved public health measures, and many diseases may be related to lifestyle choices. But animal research has contributed to understanding these factors and to the development of vaccines and lifesaving treatments. The philosophical debate regarding the benefits and moral costs of animal research has also filled many volumes by ethicists and philosophers. The major arguments against the use of animals in medical research have been explicitly refuted by a few brave scientists, as well as implicitly by the vast majority of the working biomedical science community.My contribution to this discussion is to provide a personal perspective on my decision if, when, and how to use monkeys in research experiments on Parkinson disease. As a physician researcher, I have been working for many years to understand and cure Parkinson disease.