bluuebunny/crossref_metadata_2025 huggingface dataset:
Ceria Zirconia Mixed Oxides Prepared by Hydrothermal Templating Method for the Oxidation of Ethyl Benzene
Authors: Daniel Cimi A. , Sugunan S.
Published: December 2013

CeO2–ZrO2 oxides were prepared by the surfactant-templated method using cetyl trimethyl ammonium bromide (CTAB) as template. These were characterized by XRD, FT-IR, TEM, SEM, BET and TPD-CO2. The XRD data showed that as prepared CeO2-ZrO2 powder particles have single phase cubic fluorite structure. HRTEM shows mesoscopic ordering. Average particle size is 12-13 nm as calculated from particle histogram. The nitrogen adsorption/desorption isotherm were classified to be type IV isotherm, typical of mesoporous material. The presence of uni-modal mesopores are confirmed by the pore size distribution which shows pore distribution at around 60 A°. The catalytic activities of the prepared material were tested in liquid phase oxidation of ethylbenzene with tert-butyl hydroperoxide (TBHP) as an oxidant. Ceria zirconia catalyst modified with chromium was active for ethylbenzene conversion (65.3%) with 77% selectivity towards acetophenone. © 2013 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0)
Application of Factorial Design of Experiments for the Continuous Hydrogenation of Enriched Castor Oil Methyl Esters
Authors: Neeharika Tulasi Sri Venkata Ramana , Rani Karna Narayana Prasanna , Rao Kasturi Venkata Sesha Adinarayana , Kumar Thella Prathap , Prasad Rachapudi Badari Narayana
Published: December 2013

Castor oil methyl esters contains nearly 90% ricinoleic acid (12-hydroxy-cis-9-octadecenoic acid). Hydrogen-ated castor oil methyl esters finds several applications in coating, lubricants formulations and pharmaceu-tical areas. The present study reports a fast, simple, efficient and continuous hydrogenation of enriched castor oil methyl ester (ECME) using 10% Pd/C catalyst at different pressures and temperatures. The range of process conditions for this study varied from 30-60 °C, 5-15 bar with constant flow rate of 15 ml/min. The products were analyzed for fatty acid composition and iodine value (IV). The optimized pa-rameters were found to be a temperature of 30 °C, pressure 5 bar, and flow rate of 15 ml/min where maxi-mum hydrogenation of 98.47 % was obtained and the product showed an iodine value of 3.19. © 2013 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0)
Characterization of the Picrotoxin Site of GABAA Receptors
Authors: Mehta Ashok K. , Ticku Maharaj K.
Published: December 2013

This unit describes an in vitro assay for characterization of the picrotoxin site of GABAA receptors in rat brain membranes using various radioligands. Methods and representative data for Scatchard analysis (K
d, B
max determination), association kinetics, dissociation kinetics, and competition assays (IC50, K
i determination) are included. Curr. Protoc. Pharmacol. 63:1.18.1‐1.18.18. © 2013 by John Wiley & Sons, Inc.
Analysis of Cell‐Cell Contact Mediated by Ig Superfamily Cell Adhesion Molecules
Authors: Stoeckli Esther T. , Kilinc Devrim , Kunz Beat , Kunz Stefan , Lee Gil U. , Martines Elena , Rader Christoph , Suter Daniel
Published: December 2013

Cell‐cell adhesion is a fundamental requirement for all multicellular organisms. The calcium‐independent cell adhesion molecules of the immunoglobulin superfamily (IgSF‐CAMs) represent a major subgroup. They consist of immunoglobulin folds alone or in combination with other protein modules, often fibronectin type‐III folds. More than 100 IgSF‐CAMs have been identified in vertebrates and invertebrates. Most of the IgSF‐CAMs are cell surface molecules that are membrane‐anchored either by a single transmembrane segment or by a glycosylphosphatidylinositol (GPI) anchor. Some of the IgSF‐CAMs also occur in soluble form, e.g., in the cerebrospinal fluid or in the vitreous fluid of the eye, due to naturally occurring cleavage of the GPI anchor or the membrane‐proximal peptide segment. Some IgSF‐CAMs, such as NCAM, occur in various forms that are generated by alternative splicing. This unit contains a series of protocols that have been used to study the function of IgSF‐CAMs in vitro and in vivo. Curr. Protoc. Cell Biol. 61:9.5.1‐9.5.85. © 2013 by John Wiley & Sons, Inc.
A nonstorm time enhancement of relativistic electrons in the outer radiation belt
Authors: Schiller Quintin , Li Xinlin , Blum Lauren , Tu Weichao , Turner Drew L. , Blake J. B.
Published: December 2013

Despite the lack of a geomagnetic storm (based on the Dst index), relativistic electron fluxes were enhanced over 2.5 orders of magnitude in the outer radiation belt in 13 h on 13–14 January 2013. The unusual enhancement was observed by Magnetic Electron Ion Spectrometer (MagEIS), onboard the Van Allen Probes; Relativistic Electron and Proton Telescope Integrated Little Experiment, onboard the Colorado Student Space Weather Experiment; and Solid State Telescope, onboard Time History of Events and Macroscale Interactions during Substorms (THEMIS). Analyses of MagEIS phase space density (PSD) profiles show a positive outward radial gradient from 4 < L < 5.5. However, THEMIS observations show a peak in PSD outside of the Van Allen Probes' apogee, which suggest a very interesting scenario: wave‐particle interactions causing a PSD peak at ~ L* = 5.5 from where the electrons are then rapidly transported radially inward. This letter demonstrates, for the first time in detail, that geomagnetic storms are not necessary for causing dramatic enhancements in the outer radiation belt.
Geology and composition of the Orientale Basin impact melt sheet
Authors: Spudis Paul D. , Martin Dayl J. P. , Kramer Georgiana
Published: November 2013

The Orientale Basin is one of the largest (930 km diameter) and youngest (~3.8 Ga) impact craters on the Moon. As the basin is only partly flooded by mare lava, its floor materials expose a major portion of the basin impact melt sheet, which some previous work has suggested might have undergone igneous differentiation. To test this idea, we remapped the geology of the Orientale Basin using images and topography from the Lunar Reconnaissance Orbiter, mineralogical information from the Chandrayaan‐1 Moon Mineralogy Mapper, and elemental concentration maps from Clementine multispectral imaging and Lunar Prospector gamma ray data. The Maunder Formation (impact melt sheet of the basin) is uniform in chemical composition (equivalent to “anorthositic norite”) in at least the upper 2 km of the deposit. The deepest sampling of the basin melt sheet (maximum depths of ~3–5 km by the crater Maunder, 55 km in diameter) shows a variety of lithologies, but these rock types (anorthosite, anorthositic norite melt rocks, mare basalt, and gabbro) are not those predicted by the differentiation model. We conclude that no differentiation of the Orientale Basin melt sheet has occurred and that such a process is not evident from new remote sensing data for the Moon or in the Apollo lunar samples.
Cross‐examination: The Testimony of Children With and Without Intellectual Disabilities
Authors: Bettenay Caroline , Ridley Anne M. , Henry Lucy A. , Crane Laura
Published: November 2013

The present study assessed how children with a range of cognitive abilities fared during a mock cross‐examination. Ninety children (aged 4 to 11 years; 18 with intellectual disabilities, 13 with borderline intellectual disabilities and 59 who were typically developing) witnessed a staged event, participated in an initial forensic interview (a few days later) and were cross‐examined by a barrister‐in‐training (10 months later). During cross‐examination, 98% of all children changed at least one response from their initial interview when challenged. However, group differences in performance (total number of changed responses, ‘resistance’ to challenges), controlling for age and memory for event details, were not significant or did not prove reliable at the level of individual group contrasts. Overall, little robust evidence for group differences in performance on cross‐examination could be identified, and memory for event details was the most reliable predictor of performance. Copyright © 2013 John Wiley & Sons, Ltd.
In Situ Synthesis of Bipyramidal Sulfur with 3D Carbon Nanotube Framework for Lithium–Sulfur Batteries
Authors: Wang Lina , Zhao Yu , Thomas Morgan L. , Byon Hye Ryung
Published: December 2013

A one‐pot synthesis of three‐dimensional carbon nanotube frameworks with bipyramidal sulfur particles and the application of these materials for a cathode in lithium–sulfur (Li–S) battery are reported. By simple mixing of multi‐walled carbon nanotubes (MWCNTs), sulfur powder, and capping agents in water/tetrahydrofuran, micrometer bipyramidal sulfur particles enclosed with MWCNTs are synthesized. The MWCNTs spontaneously form a 3D conducting network inside and outside the sulfur particle. Along the edge of MWCNT framework, a sulfur particle‐free region is present, which comprises ≈35 vol% based on the total volume. These sulfur‐MWCNT bipyramidal particles are mixed with conductive carbon additive to prepare binder‐free cathode for Li–S cells. The Li–S cells deliver a specific discharge capacity of ≈1600 mAh g−1 at 0.05 C on the first cycle. In particular, these Li–S cells show high rate stability and Coulombic efficiency with deep discharge and charge (1.0–3.0 V vs Li/Li+). This resultant performance can arise from 1) homogeneous distribution of the conducting MWCNT framework and the carbon additive coating layer on the sulfur particle, which allow rapid Li+ ion/electrolyte diffusion and mitigation of polysulfide shuttle, respectively, and 2) the sulfur‐free buffer space accommodating volume expansion. It is expected that this new cathode design with the simple synthetic process can reduce the number of preparation steps, thus allowing the construction of a low‐cost Li–S battery.
25th Anniversary Article: Design of Polymethine Dyes for All‐Optical Switching Applications: Guidance from Theoretical and Computational Studies
Authors: Gieseking Rebecca L. , Mukhopadhyay Sukrit , Risko Chad , Marder Seth R. , Brédas Jean‐Luc
Published: December 2013

All‐optical switching—controlling light with light—has the potential to meet the ever‐increasing demand for data transmission bandwidth. The development of organic π‐conjugated molecular materials with the requisite properties for all‐optical switching applications has long proven to be a significant challenge. However, recent advances demonstrate that polymethine dyes have the potential to meet the necessary requirements. In this review, we explore the theoretical underpinnings that guide the design of π‐conjugated materials for all‐optical switching applications. We underline, from a computational chemistry standpoint, the relationships among chemical structure, electronic structure, and optical properties that make polymethines such promising materials.
The bitter taste receptor T2R38 is an independent risk factor for chronic rhinosinusitis requiring sinus surgery
Authors: Adappa Nithin D. , Zhang Zi , Palmer James N. , Kennedy David W. , Doghramji Laurel , Lysenko Anna , Reed Danielle R. , Scott Thomas , Zhao Nina W. , Owens David , Lee Robert J. , Cohen Noam A.
Published: December 2013

Background

The bitter taste receptor T2R38 was recently described to play a role in upper airway innate mucosal defense. When activated by bacterial quorum‐sensing molecules, T2R38 stimulates the ciliated epithelial cells to produce nitric oxide (NO), resulting in bactericidal activity and an increase in mucociliary clearance (MCC). Polymorphisms within the T2R38 gene (TAS2R38) confer variability in activation of the receptor yielding dramatic differences in upper airway defensive responses (NO production and accelerated MCC) to microbial stimulation based on genotype. Our objective was to determine whether the nonprotective TAS2R38 polymorphisms, which render the receptor inactive, correlate with medically recalcitrant chronic rhinosinusitis (CRS) necessitating surgical intervention in the context of known risk factors, and thus identify whether the TAS2R38 genotype is an independent risk factor for patients undergoing functional endoscopic sinus surgery (FESS).

Methods

CRS patients undergoing primary FESS were prospectively genotyped for TAS2R38. Chi‐square analysis was performed on the genotype distribution with respect to other risk factors, including allergies, asthma, nasal polyposis, aspirin sensitivity, diabetes, and smoking exposure.

Results

Seventy primary FESS patients were genotyped demonstrating a statistically significant skewing from the expected distribution of the general population (p < 0.0383). CRS patients with a particular polymorphism seemed less likely to have allergies, asthma, nasal polyposis, aspirin sensitivity, and diabetes, but this did not demonstrate statistical significance.

Conclusion

Our investigation suggests that TAS2R38 genotype is an independent risk factor for patients failing medical therapy, necessitating surgical intervention.
Preparation and Characterization of Alkenyl Aryl Tetrafluoro‐λ6‐sulfanes
Authors: Zhong Linbin , Savoie Paul R. , Filatov Alexander S. , Welch John T.
Published: November 2013

Substituted alkenyl aryl tetrafluoro‐λ6‐sulfanes have been prepared by the direct addition of readily accessible chlorotetrafluorosulfanyl arenes to primary alkynes. Substitution of an apical fluorine of the pentafluorosulfanyl group enables modulation of the reactivity of this little explored functional group while at the same time facilitating the direct investigation of aryl substituent effects on the aryl tetrafluorosulfanyl‐substituted products.
Toward environment‐friendly composites of poly(ε‐caprolactone) reinforced with stereocomplex‐type poly(l‐lactide)/poly(d‐lactide)
Authors: Li Yi , Dong Qinglin , Han Changyu , Bian Yijie , Zhang Xin , Dong Lisong
Published: November 2013

In this work, stereocomplex‐poly(l‐ and d‐lactide) (sc‐PLA) was incorporated into poly(ε‐caprolactone) (PCL) to fabricate a novel biodegradable polymer composite. PCL/sc‐PLA composites were prepared by solution casting at sc‐PLA loadings of 5–30 wt %. Differential scanning calorimetry (DSC) and wide‐angle X‐ray diffraction (WAXD) demonstrated the formation of the stereocomplex in the blends. DSC and WAXD curves also indicated that the addition of sc‐PLA did not alter the crystal structure of PCL. Rheology and mechanical properties of neat PCL and the PCL/sc‐PLA composites were investigated in detail. Rheological measurements indicated that the composites exhibited evident solid‐like response in the low frequency region as the sc‐PLA loadings reached up to 20 wt %. Moreover, the long‐range motion of PCL chains was highly restrained. Dynamic mechanical analysis showed that the storage modulus (E′) of PCL in the composites was improved and the glass transition temperature values were hardly changed after the addition of sc‐PLA. Tensile tests showed that the Young's modulus, and yield strength of the composites were enhanced by the addition of sc‐PLA while the tensile strength and elongation at break were reduced. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40208.
Standardisiertes Einwirkungsmodell zur Bemessung von Wildbachsperren unter Mureinwirkung
Authors: Suda Jürgen , Hübl Johannes , Rudolf‐Miklau Florian
Published: December 2013

Wildbachschutzbauwerke mit energieumwandelnder, filternder oder ablenkender Funktion für Muren unterliegen extremen dynamischen Beanspruchungen und hohen Sicherheitsanforderungen an die Bemessung, die Konstruktion und den Betrieb. Die neue ONR 24801enthält ein standardisiertes Modell zur Bemessung von Wildbachsperren unter Mureinwirkung, welches aus der Vergleichsrechnung gängiger Murenmodelle entwickelt und mit Messergebnissen von Murereignissen kalibriert wurde. Das Modell basiert auf einem statisch‐dynamisch gemischten Lastansatz und berücksichtigt auch den Anprall von Einzelkomponenten (Blöcke, Baumstämme) auf das Bauwerk. Der dynamische Teil der Mureinwirkung wird von einem charakteristischen Gerinnequerschnitt auf eine flächengleiche Einwirkungsfläche im zentralen Teil der Sperre übertragen, zusätzlich wird ein statischer Murdruck über die gesamte Bauwerkshöhe angesetzt. Das Modell wurde bereits an einigen Sperrenbauwerken erprobt und stimmt gut mit den in Österreich üblichen Bemessungsansätzen für Wildbachsperren überein.

Standardized load model for design of torrential barriers under debris flow impact

Torrential barriers with energy‐dissipating, filtering or deflecting function for debris flow are subject to extreme dynamic stress that presupposes the application of high safety standards for design, construction and maintenance. The newly issued Austrian Standard ONR 24801 provides a standardized model for the design of torrential barriers under debris flow impact, which has been developed from comparative calculation of common debris flow models from engineering practice in torrent control and calibrated by impact measurements of debris flow events. The model is based on a combined static‐dynamic stress approach and also takes into account the impulse by a single object (block, tree trunk). The dynamic part of the debris flow stress is transferred from a characteristic cross‐section in the torrent to a vertical impact area of same dimension on the central part of the barrier; additionally static debris flow stress is applied. The standardized model was already tested successfully at several torrential barriers and is in good agreement with the common design approaches (experiences) of torrent control in Austria.
Nachweis von Strukturdefekten und Einbauteilen in Elementwänden mittels zerstörungsfreier Prüfverfahren
Authors: Mähner Dietmar , Thünemann Stefan , Becker Markus
Published: December 2013

Im Rahmen eines Ringversuchs wurden verschiedene Strukturdefekte und Einbauteile in Elementwände eingebaut. Die Messung der Wände erfolgte anschließend durch mehrere Messteams mit unterschiedlichen zerstörungsfreien Prüfverfahren. Zum Einsatz kamen hierbei das Ultraschall‐Echo‐ und das Impact‐Echo‐Verfahren sowie das Impuls‐Radar‐Verfahren. Zur Verbesserung der Vergleichbarkeit zwischen den unterschiedlichen Prüfverfahren wurde auf die Elementwände ein einheitliches Messraster aufgebracht. Für eine möglichst objektive Messung der Wände erhielten die Messteams vor den Messungen keine Detailinformationen zu den Strukturdefekten oder Einbauteilen. Die Prüfaufgabe bestand darin, die Wände mit dem jeweiligen Prüfverfahren zu untersuchen. Anschließend wurden die Ergebnisse der Messteams zentral gesammelt und ausgewertet. Anhand der zentralen Auswertung sollten Aussagen zu den eingebauten Inhomogenitäten abgeleitet werden. Hierdurch kann zum einen die Leistungsfähigkeit der Prüfverfahren an unterschiedlichsten Inhomogenitäten getestet werden, zum anderen können die Ergebnisse und somit die Prüfverfahren untereinander verglichen werden. Zu diesen in der Praxis immer häufiger vorkommenden Fragestellungen können grundsätzliche Aussagen zum Einsatz von zerstörungsfreien Prüfungen bei Elementwänden erhalten werden. Über die Ergebnisse dieses Ringversuchs wird nachfolgend berichtet.

Detection of structural defects and built‐in parts in prefabricated walls using non‐destructive testing methods

In cooperative tests, different structural defects and built‐in parts were embedded in prefabricated walls. Series of tests for measurement were conducted by several researchers, using three different non‐destructive testing methods: Ultrasonic‐Echo, Impact‐Echo and Impulse‐Radar Technique. To increase comparison between testing methods, a standardized measuring grid was placed on the prefabricated walls. For objective results researchers did not get any detailed information in regard to the structural defects or built‐in parts. Testing task was to scan the walls, using the described methods. To derive conclusions about the embedded inhomogeneities, data was centrally selected/pooled and analyzed. Hereby the effectiveness of testing methods can be validated and results hence testing methods can be compared. For the described incidences, essential conclusions can be obtained for using of non‐destructive testing methods in prefabricated walls. Results of the investigation will be reported in the following article.
Relative Luftfeuchtemessung zur Erfassung der Wassersättigung von Beton
Authors: Pruckner Franz
Published: December 2013

Eine Möglichkeit der Erfassung des Wassersättigungsgrads von Beton stellt die Messung der relativen Luftfeuchtigkeit eines mit dem Beton im Gleichgewicht stehenden Hohlraums dar. Die indirekte Natur dieser Methode erfordert die Kenntnis der thermodynamischen Zusammenhänge, um brauchbare Informationen zur Wassersättigung zu erhalten. Die Berechnung der Wassersättigung erfordert sowohl die Erfassung der Luftfeuchtigkeit als auch der Temperatur. In der vorliegenden Arbeit werden die Ergebnisse dieser Methode dargestellt. Interessant war die Beobachtung, dass die Wassersättigung von beschichteten Bauteilen konstant blieb, obwohl sich die gemessene Luftfeuchtigkeit im Hohlraum mit den täglichen und saisonalen Temperaturschwankungen änderte.

Relative humidity measurements for assessing moisture conditions in concrete structures

One way of detecting the water saturation degree of concrete represents the measurement of the relative humidity in a cavity in concrete which is in equilibrium with moisture content in concrete. The indirect nature of this method requires knowledge of the thermodynamic relationships in order to obtain useful information on water saturation. Calculating the water saturation degree of concrete requires both detection of the humidity and the temperature. In the present study, the results of this method are presented. It was interesting to observe that the saturation degree of coated concrete structures remained constant, even though the measured humidity in the cavity changed with the daily and seasonal temperature fluctuations.
Spannbetonuntersuchung mit bildgebenden Ultraschallecho‐Verfahren
Authors: Schulze Sebastian , Mayer Klaus , Krause Martin
Published: December 2013

Beim Einsatz von Ultraschallecho‐Methoden in der zerstörungsfreien Prüfung im Bauwesen stellt die Untersuchung von Spannbetonkonstruktionen eine der anspruchsvollsten Aufgaben für Wissenschaft und Technik dar. Das inhomogene Gefüge aus Beton, schlaffer Bewehrung und – aus Hüllrohr, Spannlitzen und Verpressmörtel bestehenden – Spanngliedern erfordert eine Optimierung von Messtechnik und Auswertesoftware, um verwertbare Aussagen zum Verpresszustand der Hüllrohre zu erhalten. Der vorliegende Beitrag beschreibt die Grundlagen der bildgebenden Darstellung von US‐Echo‐Daten, die Untersuchung und Datenauswertung an Probekörpern sowie ein Fallbeispiel aus der Praxis. Dabei erweist sich insbesondere die Phasenauswertung zur qualitativen Unterscheidung von Reflektoren als nützlich. Das Prinzip wird erläutert, und es werden Teile eines interaktiven, auf der SAFT‐Methode basierenden Softwarepakets vorgestellt. Mit dieser Software können die großflächig gewonnenen Ultraschalldaten auf herkömmlichen PCs oder mobilen Computern zu zwei‐ und dreidimensionalen Rekonstruktionen berechnet, analysiert und visualisiert werden. Ausgewertet wurden Daten, die mit automatisierten Messsystemen an kleinformatigen Laborprobekörpern und großen Testwänden gewonnen wurden. Im Rahmen der praktischen Anwendung konnten unter Verwendung der vorgestellten Verfahren an einem Spannglied die Lage eines Hüllrohrverstopfers lokalisiert und die Ausdehnung der Blockadestelle eingegrenzt werden.

Investigation of prestressed concrete using the imaging ultrasonic echo method – Application of phase evaluation for the distinction of reflectors: The application of ultrasound methods for the non‐destructive assessment of pre‐stressed concrete members is one of the biggest challenges in the field of non‐destructive testing in civil engineering. The inhomogeneous composition of concrete, reinforcement and tendons, which itself consist of ducts, steel wires and grouting material, requires an optimisation of measuring technique and analysis software to gain reliable information about the grouting condition of the ducts. This article describes the fundamentals of the visualisation of ultrasound echo data, the investigation and data analysis at specimen and a case study. Here especially the phase evaluation proves to be very useful for the distinction of reflectors. The basic principle is explained and parts of an interactive software module, which is based on the SAFT method, is presented. With this software it is possible to calculate, analyse and visualise 2D and 3D reconstructions of large ultrasound data sets with conventional PCs or mobile computers. Data has been analysed, which were recorded with automatic measurement systems at small scale laboratory specimens and a large scale testing wall. In the frame of the practical application it was possible to localise the position and extent of a blockade within a duct.
Entwicklung und Anwendung eines Baustellenmessgeräts zur Bestimmung der Spannung in Bewehrungsstählen
Authors: Gundelwein Harald , Zellweger Werner
Published: December 2013

Die Kenntnis der in einem bestehenden Stahlbeton‐ oder Spannbetonbauwerk herrschenden Spannung in den Bewehrungsstählen ist ein wichtiger Parameter für die Tragwerksbeurteilung. Bei der rechnerischen Ermittlung der Spannung in der Bewehrung müssen viele Annahmen zu Bauteilabmessungen, Steifigkeiten und Lasten getroffen werden, die das Ergebnis stark beeinflussen. Eine messtechnische Ermittlung der Stahlspannung mit zerstörungsfreien Prüfmethoden wäre deshalb sehr hilfreich. Die enertec engineering ag in Winterthur hat ein solches Messgerät zur Anwendungsreife entwickelt. Das auf der Messung von mikromagnetischen Eigenschaften beruhende Verfahren wird beschrieben, die praktische Anwendung erläutert und der Nutzen anhand von zwei durchgeführten Messkampagnen aufgezeigt.

Development and practice of a new device for the measurement of mechanical stress in the reinforcement of concrete structures

The knowledge of the mechanical stress in the reinforcement of existing concrete structures is a vital parameter for the evaluation of these structures. At the calculation of the tension in the reinforcement using static models there have to be assumed values for geometry, stiffness and load, which have a crucial impact on the result. For this reason the measurement of the existant stress in the reinforcement with nondestructive methods would be very helpful. The enertec engineering ag in Winterthur, Switzerland has developed such a measuring device for practical use on site. The physical methods and the practical use are described. The advantages of the deployment of the device are shown on two executed measuring campaigns.
Auflösung der Nebel – Leben in Sicht!
Authors: Mirwald Benjamin
Published: December 2013

Resolving Nebulae – Life in Sight! While in the second half of the 19th century astrospectroscopy and ‐photography had contoured new objects of investigation like nebulae, the debate among astronomers about extraterrestrial life intensified. Images did not only play a key role in uprising popular astronomical magazines at that time, they also served as arguments or even as evidence in controversial debates about the nature of nebulae or of planets' surfaces. These debates were not restricted to academic astronomers, on the contrary, amateurs and popularisers were among the most active disputants. Photos and images published in popular magazines were more intensively retouched or manipulated than when they were used in academic communication about astronomy. But the practices of interpretation and speculation, based on drawings and images, stemmed from academic communities. Far reaching conclusions relying on unclear features of astronomical pictures, like in the case of Martian canals, have not only been criticised by other academics. History shows that the ability to scrutinise imaginations about evidence of life in space or about the forming of the solar system was due more to tacitly knowing how images were produced than to having an encyclopaedic recall in astronomy.
Linus Pauling, Roger Hayward und der Wert von Sichtbarmachungen
Authors: Heumann Ina
Published: December 2013

Linus Pauling, Roger Hayward, and the Value of Visualizations. Linus Pauling's work was intrinsically linked to visualizations. While his use of three‐ and two‐dimensional inscriptions has been the focus of much scholarly research, the production of visualizations remains a rather poorly studied subject. This article focuses on the cooperation between Pauling and Roger Hayward, an architect by profession who came to scientific illustration in the late 1920s. By concentrating on the papers of Pauling and Hayward I describe the workflow between scientist and illustrator. Although Hayward's visualizations were epistemically indispensable and economically profitable, they were never fully acknowledged as such. This was due to the ongoing conflicts caused by the economic strategies pursued by Pauling and his publisher, Hayward's personal style, and science's general disregard for images as epistemic instruments. I suggest that these contentious relationships between scientist, illustrator, and publisher are paradigmatic for the history of scientific visualization.
Hot‐Spot Residues in the Cytochrome P450cam–Putidaredoxin Binding Interface
Authors: Hiruma Yoshitaka , Gupta Ankur , Kloosterman Alexander , Olijve Caroline , Ölmez Betül , Hass Mathias A. S. , Ubbink Marcellus
Published: December 2013

Cytochrome P450cam (P450cam) is a heme‐containing monooxygenase that catalyzes the hydroxylation of D‐camphor to produce 5‐exo‐hydroxycamphor. The catalytic cycle of P450cam requires two electrons, both of which are donated by putidaredoxin (Pdx), a ferredoxin containing a [2 Fe–2 S] cluster. Atomic‐resolution structures of the Pdx‐P450cam complex have recently been solved by X‐ray crystallography and paramagnetic NMR spectroscopy. The binding interface showed the potential electron transfer pathways and interactions between Pdx Asp38 and P450cam Arg112, as well as hydrophobic contacts between the Pdx Trp106 and P450cam residues. Several polar residues not previously recognized as relevant for binding were found in the interface. In this study, site‐directed mutagenesis, kinetic measurements, and NMR studies were employed to probe the energetic importance and role of the polar residues in the Pdx–P450cam interaction. A double mutant cycle (DMC) analysis of kinetic data shows that favorable interactions exist between Pdx Tyr33 and P450cam Asp125, as well as between Pdx Ser42 and P450cam His352. The results show that alanine substitutions of these residues and several others do not influence the rates of electron transfer. It is concluded that these polar interactions contribute to partner recognition rather than to electronic coupling of the redox centers.
Specificity of a UDP‐GalNAc Pyranose–Furanose Mutase: A Potential Therapeutic Target for Campylobacter jejuni Infections
Authors: Poulin Myles B. , Shi Yun , Protsko Carla , Dalrymple Sean A. , Sanders David A. R. , Pinto B. Mario , Lowary Todd L.
Published: December 2013

Pyranose–furanose mutases are essential enzymes in the life cycle of a number of microorganisms, but are absent in mammalian systems, and hence represent novel targets for drug development. To date, all such mutases show preferential recognition of a single substrate (e.g., UDP‐Gal). We report here the detailed structural characterization of the first bifunctional pyranose–furanose mutase, which recognizes both UDP‐Gal and UDP‐GalNAc. The enzyme under investigation (cjUNGM) is involved in the biosynthesis of capsular polysaccharides (CPSs) in Campylobacter jejuni 11168. These CPSs are known virulence factors that are required for adhesion and invasion of human epithelial cells. Using a combination of UV/visible spectroscopy, X‐ray crystallography, saturation transfer difference NMR spectroscopy, molecular dynamics and CORCEMA‐ST calculations, we have characterized the binding of the enzyme to both UDP‐Galp and UDP‐GalpNAc, and compared these interactions with those of a homologous monofunctional mutase enzyme from E. coli (ecUGM). These studies reveal that two arginines in cjUNGM, Arg59 and Arg168, play critical roles in the catalytic mechanism of the enzyme and in controlling its specificity to ultimately lead to a GalfNAc‐containing CPS. In ecUGM, these arginines are replaced with histidine and lysine, respectively, and this results in an enzyme that is selective for UDP‐Gal. We propose that these changes in amino acids allow C. jejuni 11168 to produce suitable quantities of the sugar nucleotide substrate required for the assembly of a CPS containing GalfNAc, which is essential for viability.
Rhodium‐Catalyzed Intramolecular Hydroarylation of 1‐Halo‐1‐alkynes: Regioselective Synthesis of Semihydrogenated Aromatic Heterocycles
Authors: Murase Hirohiko , Senda Kousuke , Senoo Masato , Hata Takeshi , Urabe Hirokazu
Published: December 2013

The regioselective intramolecular hydroarylation of (3‐halo‐2‐propynyl)anilines, (3‐halo‐2‐propynyl) aryl ethers, or (4‐halo‐3‐butynyl) aryl ethers was efficiently catalyzed by Rh2(OCOCF3)4 to give semihydrogenated aromatic heterocycles, such as 4‐halo‐1,2‐dihydroquinolines, 4‐halo‐3‐chromenes, or 4‐(halomethylene)chromans, in good to excellent yields. Some synthetic applications taking advantage of the halo‐substituents of the products are also illustrated.
NMR Spectroscopy and X‐Ray Characterisation of Cationic N‐Heteroaryl‐Pyridylamido ZrIV Complexes: A Further Level of Complexity for the Elusive Active Species of Pyridylamido Olefin Polymerisation Catalysts
Authors: Li Gang , Zuccaccia Cristiano , Tedesco Consiglia , D'Auria Ilaria , Macchioni Alceo , Pellecchia Claudio
Published: November 2013

New [(N−,N,N−)ZrR2] dialkyl complexes (N−,N,N−=pyrrolyl‐pyridyl‐amido or indolyl‐pyridyl‐amido; R=Me or CH2Ph) have been synthesised and tested as pre‐catalysts for ethene and propene polymerisation in combination with different activators, such as B(C6F5)3, [Ph3C][B(C6F5)4], [HNMe2Ph][B(C6F5)4] or solid AlMe3‐depleted methylaluminoxane (DMAO). Polyethylene (Mw>2 MDa and Mw/Mn = 1.3–1.6) has been produced if pre‐catalysts were activated with 1000 equivalents of DMAO (based on Al) [activity >1000 kgPE (mol[Zr] h mol atm)−1] or by using a higher pre‐catalyst concentration and a mixture of [HNPhMe2][B(C6F5)4] (1 equiv) and AliBu2H (60 equiv). In the case of propene polymerisation, activity has been observed only if pre‐catalysts were treated with an excess of AliBu2H prior to addition of DMAO, which led to highly isotactic polypropylene ([mmmm]>95 %). Neutral pre‐catalysts and ion pairs derived from their activation have been characterised in solution by using advanced 1D and 2D NMR spectroscopy experiments. The detection and rationalisation of intercationic NOEs clearly showed the formation of dimeric species in which some pyrrolyl or indolyl π‐electron density of one unit is engaged in stabilising the metal centre of the other unit, which relegates the counterions in the second coordination sphere. The solid‐state structure of the dimeric indolyl‐pyridyl‐amidomethylzirconium derivative, determined by X‐ray diffraction studies, points toward a weak Zr⋅⋅⋅η3‐indolyl interaction. It can be hypothesised that the formation of dimeric cationic species hampers monomer coordination (especially of less reactive α‐olefins) and that addition of AliBu2H is crucial to split the homodimers.
Planar and Nonplanar Free‐Base Tetraarylporphyrins: β‐Pyrrole Substituents and Geometric Effects on Electrochemistry, Spectroelectrochemistry, and Protonation/Deprotonation Reactions in Nonaqueous Media
Authors: Fang Yuanyuan , Bhyrappa P. , Ou Zhongping , Kadish Karl M.
Published: December 2013

A series of planar and nonplanar free‐base β‐pyrrole substituted meso‐tetraarylporphyrins were characterized by electrochemistry, spectroelectrochemistry, and protonation or deprotonation reactions in neutral, acidic, and basic solutions of CH2Cl2. The neutral compounds are represented as H2(P), in which P represents a porphyrin dianion with one of several different sets of electron‐withdrawing or ‐donating substituents at the messo and/or β‐pyrrole positions of the macrocycle. The conversion of H2(P) to [H4(P)]2+ in CH2Cl2 was accomplished by titration of the neutral porphyrin with trifluoroacetic acid (TFA) while the progress of the protonation was monitored by UV/Vis spectroscopy, which was also used to calculate logβ2 for proton addition to the core nitrogen atoms of the macrocycle. Cyclic voltammetry was performed after each addition of TFA or TBAOH to CH2Cl2 solutions of the porphyrin and half‐wave potentials for reduction were evaluated as a function of the added acid or base concentration. Thin‐layer spectroelectrochemistry was used to obtain UV/Vis spectra of the neutral and protonated or deprotonated porphyrins under the application of an applied reducing potential. The magnitude of the protonation constants, the positions of λmax in the UV/Vis spectra and the half‐wave or peak potentials for reduction are then related to the electronic properties of the porphyrin and the data evaluated as a function of the planarity or nonplanarity of the porphyrin macrocycle. Surprisingly, the electroreduction of the diprotonated nonplanar porphyrins in acid media leads to H2(P), whereas the nonplanar H2(P) derivatives are reduced to [(P)]2− in CH2Cl2 containing 0.1 M tetra‐n‐butylammonium perchlorate (TBAP). Thus, in both cases an electrochemically initiated deprotonation is observed.
1,2,3‐Triazolo[4,5,‐e]furazano[3,4,‐b]pyrazine 6‐Oxide—A Fused Heterocycle with a Roving Hydrogen Forms a New Class of Insensitive Energetic Materials
Authors: Thottempudi Venugopal , Yin Ping , Zhang Jiaheng , Parrish Damon A. , Shreeve Jean'ne M.
Published: November 2013

The straightforward synthesis and energetic properties of a new class of energetic materials, 1,2,3‐triazolo‐ [4,5‐e]furazano[3,4‐b]pyrazine 6‐oxide and its energetic salts are described. They were characterized by IR and multinuclear NMR spectroscopy, elemental analysis, differential scanning calorimetry, and single‐crystal X‐ray diffraction are given. The X‐ray structures show that in the title compound, the hydrogen atom is bonded to the nitrogen in the pyrazine ring; however, in the salts, the negative charge is associated with the triazole nitrogen. Heats of formation for all compounds were calculated with the G2 method and then combined with experimentally determined densities to obtain detonation pressures (P) and velocities (D) by using EXPLO5 program. These new materials exhibit good densities and thermal stabilities, high heats of formation, acceptable detonation properties, and are insensitive to impact.
From Diphosphino‐Functionalized 1,3‐Dialkylimidazolium Cations to Imidazolones through Dehydrogenative CN Coupling
Authors: Ruiz Javier , Mesa Alejandro F.
Published: November 2013

Diphosphino‐functionalized 1,3‐dialkylimidazolium salts react with KOH affording amine/formamide open‐chain products, which fully revert to the imidazolium cation by treatment with a variety of acids or are converted to 2‐imidazolones by noncatalyzed intramolecular dehydrogenative CN coupling, a process that is modulated by coordination of the phosphino functionalities to transition metals.
ChemInform Abstract: Thermoluminescent Dosimetry Properties of Double Doped Calcium Tetraborate (CaB4O7:Cu—Mn) Nanophosphor Exposed to γ‐Radiation.
Authors: Haghiri Maryam Erfani , Saion Elias , Soltani Nayereh , wan Abdullah Wan Saffiey , Navasery Manizheh , Saraee Khadijeh Rezaee Ebrahim , Deyhimi Najmeh
Published: December 2013

The title nanophosphor is synthesized from CaCl2, Na2B4O7, MnCl2, and CuCl2 in polyvinyl pyrrolidone solution at 48 °C.
ChemInform Abstract: Functionalization Based on the Substitutional Flexibility: Strong Middle IR Nonlinear Optical Selenides AXII4XIII5Se12.
Authors: Lin Hua , Chen Ling , Zhou Liu‐Jiang , Wu Li‐Ming
Published: December 2013

MIMII4MIII5 Se12 (MI: K—Cs; MII: Mn, Cd; MIII: Ga, In) are prepared by melting of stoichiometric mixtures of the elements using MICl as flux (evacuated silica tubes, 1273 K, 4 d).
ChemInform Abstract: Preparation and Electrochemical Performance of LiNi0.5Mn0.5O2‐xFx (0 ≤ x ≤ 0.04) Cathode Material Synthesized with Hydroxide Co‐Precipitation for Lithium Ion Batteries.
Authors: Hu Chuanyue , Guo Jun , Wen Jin , Peng Yangxi , Chen Yan
Published: December 2013

The title solid solution is prepared by solid state reaction of stoichiometric mixtures of Ni0.5Mn0.5(OH)2, Li2CO3, and LiF (900—950 °C, 20—40 h).
ChemInform Abstract: Two‐Step Hydrothermal Process for Synthesis of F‐Doped BiVO4 Spheres with Enhanced Photocatalytic Activity.
Authors: Li Jun‐Qi , Guo Zhan‐Yun , Liu Hui , Du Juan , Zhu Zhen‐Feng
Published: December 2013

Pure BiVO4 spheres are prepared from mixtures of Bi(NO3)3 dissolved in HNO3 and NH4VO3 dissolved in NaOH solution (autoclave, microwave irradiation, 180 °C, 3 h).
ChemInform Abstract: Special ∞1[OPb2] Chains and ∞1[O2Pb3] Ribbons Based on OPb4 Anion‐Centered Tetrahedra in Pb2(O4Pb8) (BO3)3Br3 and Pb2(O8Pb12) (BO3)2Br6.
Authors: Dong Lingyun , Pan Shilie , Wang Ying , Yu Hongwei , Dong Xiaoyu , Han Shujuan , Zhang Min
Published: December 2013

The crystal structures of the new compounds (IV) and (V) are determined by single crystal XRD.
ChemInform Abstract: Crystalline and Glassy Phases in the Cs/Bi/As/S System.
Authors: Bera Tarun K. , Iyer Ratnasabapathy G. , Malliakas Christos D. , Kanatzidis Mercouri G.
Published: December 2013

The new crystalline compounds (V) and (VI) are obtained using fluxes with low As content.
ChemInform Abstract: Enantioselective Synthesis of Quaternary Carbon Stereogenic Centers Through Copper‐Catalyzed Conjugate Additions of Aryl‐ and Alkylaluminum Reagents to Acyclic Trisubstituted Enones.
Authors: Dabrowski Jennifer A. , Villaume Matthew T. , Hoveyda Amir H.
Published: December 2013

The title reaction allows a new, efficient, and widely applicable method to prepare ketones bearing an all‐carbon quaternary stereogenic center at β position.
ChemInform Abstract: Lewis Base Directed Cycloaddition Reactions of 2‐Pyrones and Alkynylaluminum Reagents.
Authors: Crepin Damien F. , Harrity Joseph P. A.
Published: December 2013

In situ prepared alkynylaluminum derivatives are used as novel 2π compounds in [4 + 2] cycloadditions with 2‐pyrans bearing amides or N‐heteroarenes as directing groups.
ChemInform Abstract: Direct Esterification of Carboxylic Acids with Alcohols Catalyzed by Iron(III) Acetylacetonate Complex.
Authors: Weng Shiue‐Shien , Chen Fong‐Kuang , Ke Chih‐Shuch
Published: December 2013

Esterification catalyzed by iron(III) acetylacetonate does not only offer important advantages such as recoverability of the catalyst and inexpensive starting material, but can also be applied to a variety of primary and secondary alcohols and complex carboxylic acids including unmasked α‐hydroxyacid, heterocyclic, and N‐protected amino acids without the need for any dehydration reagent.
ChemInform Abstract: Alkylation and Ring Opening of Perfluoroalkyl‐ and Perfluoroaryl‐Substituted 2‐Siloxycyclopropanecarboxylates Yielding Fluorinated γ‐Oxo Esters or β,γ‐Unsaturated Ketones.
Authors: Gladow Daniel , Reissig Hans‐Ulrich
Published: December 2013

Deprotonation of title compounds (I) and subsequent alkylation furnishes C1‐alkylated cyclopropanes (III) with high diastereoselectivity.
ChemInform Abstract: Lewis Acid‐Catalyzed Regioselective Synthesis of Chiral α‐Fluoroalkyl Amines via Asymmetric Addition of Silyl Dienolates to Fluorinated Sulfinylimines.
Authors: Liu Yingle , Liu Jiawang , Huang Yangen , Qing Feng‐Ling
Published: December 2013

The asymmetric addition of silyl dienolates (II) to sulfinylimines (I) in the presence of catalytic amounts of AgBF4 leads to the α‐adducts (III) as major products, whilst the use of Tms‐O‐Tf as catalyst affords predominantly the γ‐adducts (IV).
ChemInform Abstract: Copper‐Catalyzed Synthesis of α,β‐Unsaturated Acylamides via Direct Amidation from Cinnamic Acids and N‐Substituted Formamides.
Authors: Yan Hong , Yang Hailong , Lu Linhua , Liu Defu , Rong Guangwei , Mao Jincheng
Published: December 2013

An efficient synthesis of α,β‐unsaturated acylamides via copper‐catalyzed direct amidation between readily available cinnamic acids and N‐substituted formamides is reported for the first time.
ChemInform Abstract: Reaction of Trisubstituted Alkenes with Iron Porphyrin Carbenes: Facile Synthesis of Tetrasubstituted Dienes and Cyclopentadienes.
Authors: Wang Peng , Liao Saihu , Wang Sunewang R. , Gao Run‐Duo , Tang Yong
Published: December 2013

A carbene transfer reaction to trisubstituted alkenes (I) and (V) mediated by iron‐porphyrin catalysis is realized based on an ylidic approach.
ChemInform Abstract: Sandmeyer Trifluoromethylation of Arenediazonium Tetrafluoroborates.
Authors: Danoun Gregory , Bayarmagnai Bilguun , Gruenberg Matthias F. , Goossen Lukas J.
Published: December 2013

The newly developed Sandmeyer trifluoromethylation is applicable to differently substituted arenediazonium salts.
ChemInform Abstract: Synthesis of Nitroalkenes Involving a Cooperative Catalytic Action of Iron(III) and Piperidine: A One‐Pot Synthetic Strategy to 3‐Alkylindoles, 2H‐Chromenes and N‐Arylpyrrole
Authors: Jalal Swapnadeep , Sarkar Soumen , Bera Krishnendu , Maiti Sukhendu , Jana Umasish
Published: December 2013

For the first time the preparation of nitroalkenes involving a cooperative catalyst is presented.
ChemInform Abstract: Development of Second Generation Gold‐Supported Palladium Material with Low‐Leaching and Recyclable Characteristics in Aromatic Amination.
Authors: Arisaw Mitsuhiro , et al. et al.
Published: December 2013

The newly prepared catalyst is tested in ligand‐free Buchwald—Hartwig cross‐coupling reactions of aryl halides with primary and secondary amines.
ChemInform Abstract: Nano CoFe2O4 as a Magnetically Separable Catalyst for the Solvent‐Free Synthesis of Formamides under Ultrasound Irradiation at Room Temperature.
Authors: Bahari Siavash
Published: December 2013

A protocol for the ultrasound assisted formylation of secondary and primary amines is described.
ChemInform Abstract: Ruthenium‐Containing Phosphinesulfonate Chelate for the Hydrogenation of Aryl Ketones.
Authors: Jiang Fan , Yuan Kedong , Achard Mathieu , Bruneau Christian
Published: December 2013

Ruthenium phosphate complexes are described as catalyst for the hydrogenation of aryl alkyl ketones.
ChemInform Abstract: Novel and Selective Synthesis of Unsymmetrical Azine Derivatives via a Mild Reaction.
Authors: Safari Javad , Gandomi‐Ravandi Soheila , Monemi Mohammad
Published: December 2013

Title compounds (III) are conveniently and selectively prepared using a benign one‐step procedure without formation of any symmetrical azine.
ChemInform Abstract: Highly Enantioselective Synthesis of N‐Protected β‐Amino Malonates Catalyzed by Magnetically Separable Heterogeneous Rosin‐Derived Amino Thiourea Catalysts: A Stereocontrolled Approach to β‐Amino Acids.
Authors: Zhu Hao , Jiang Xianxing , Li Xinghua , Hou Chen , Jiang Yu , Hou Ke , Wang Rui , Li Yanfeng
Published: December 2013

Both enantiomers of the catalyst can be used with comparable results.
ChemInform Abstract: The Supersilyl Group as a Carboxylic Acid Protecting Group: Application to Highly Stereoselective Aldol and Mannich Reactions.
Authors: Tan Jiajing , Akakura Matsujiro , Yamamoto Hisashi
Published: December 2013

The silyl group ‐Si(SiEt3)3 is used for the first time as stable and effective protecting group in the title reactions.
ChemInform Abstract: A Novel Copper‐Catalyzed Synthesis of Functionalized Alkynyl Imidates and Alkynyl Thioimidates.
Authors: Yavari Issa , Nematpour Manijeh
Published: December 2013

The reaction of acetonitrile with benzylalcohols or benzylmercaptans generates trichloroimidates which undergo a Cu‐catalyzed reaction with terminal alkynes to give the title compounds.
ChemInform Abstract: Calcined Eggshell (CES): An Efficient Natural Catalyst for Knoevenagel Condensation under Aqueous Condition.
Authors: Patil Suresh , Jadhav Swati D. , Deshmukh M. B.
Published: December 2013

A highly efficient, green, and mild method for the Knoevenagel condensation of aromatic aldehydes with active methylene compounds is developed.