bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phosphine‐Initiated Cation Exchange for Precisely Tailoring Composition and Properties of Semiconductor Nanostructures: Old Concept, New Applications
Authors: Gui Jing , Ji Muwei , Liu Jiajia , Xu Meng , Zhang Jiatao , Zhu Hesun 
Published: February 2015

AbstractPhosphine‐initiated cation exchange is a well‐known inorganic chemistry reaction. In this work, different phosphines have been used to modulate the thermodynamic and kinetic parameters of the cation exchange reaction to synthesize complex semiconductor nanostructures. Besides preserving the original shape and size, phosphine‐initiated cation exchange reactions show potential to precisely tune the crystallinity and composition of metal/semiconductor core–shell and doped nanocrystals. Furthermore, systematic studies on different phosphines and on the elementary reaction mechanisms have been performed.
An Efficient Approach to Chiral Allyloxyamines by Stereospecific Allylation of Nitrosoarenes with Chiral Allylboronates
Authors: Li Yuanming , Chakrabarty Shyamal , Studer Armido 
Published: February 2015

AbstractA novel and efficient approach to allyloxyamines by the allylation of nitrosoarenes with α‐chiral allylboronates is described. CO bond formation occurs with high stereospecificity and the product allyloxyamines are easily transformed into valuable chiral building blocks such as isoxazolidines and allylic alcohols. The reaction features complete regioselectivity (O‐selectivity), high E/Z selectivity, and excellent chirality transfer.
A New Way to Silicone‐Based Peptide Polymers
Authors: Jebors Said , Ciccione Jeremie , Al‐Halifa Soultan , Nottelet Benjamin , Enjalbal Christine , M'Kadmi Céline , Amblard Muriel , Mehdi Ahmad , Martinez Jean , Subra Gilles 
Published: February 2015

AbstractWe describe a new class of silicone‐containing peptide polymers obtained by a straightforward polymerization in water using tailored chlorodimethylsilyl peptide blocks as monomeric units. This general strategy is applicable to any type of peptide sequences, yielding linear or branched polymer chains composed of well‐defined peptide sequences.
Stereochemical Assignment of the Protein–Protein Interaction Inhibitor JBIR‐22 by Total Synthesis
Authors: Healy Alan R. , Izumikawa Miho , Slawin Alexandra M. Z. , Shin‐ya Kazuo , Westwood Nicholas J. 
Published: February 2015

AbstractRecent reports have highlighted the biological activity associated with a subfamily of the tetramic acid class of natural products. Despite the fact that members of this subfamily act as protein–protein interaction inhibitors that are of relevance to proteasome assembly, no synthetic work has been reported. This may be due to the fact that this subfamily contains an unnatural 4,4‐disubstitued glutamic acid, the synthesis of which provides a key challenge. A highly stereoselective route to a masked form of this unnatural amino acid now enabled the synthesis of two of the possible diastereomers of JBIR‐22 and allowed the assignment of its relative and absolute stereochemistry.
An Affinity Reagent for the Recognition of Pyrophosphorylated Peptides
Authors: Conway John H. , Fiedler Dorothea 
Published: February 2015

AbstractA resin‐bound dinuclear zinc(II) complex for the selective capture of pyrophosphopeptides is reported. The metal complex binds diphosphate esters over other anionic groups, such as monophosphate esters, sulfate esters, and carboxylic acids, with high specificity. Immobilization of the compound provided a reagent capable of binding and retaining nanomolar quantities of pyrophosphopeptide in the presence of cell lysate. The high affinity and specificity of the reagent makes it an attractive tool for the study of in vivo pyrophosphorylation.
Palladium‐Catalyzed Regio‐ and Stereoselective Cross‐Addition of Terminal Alkynes to Ynol Ethers and Synthesis of 1,4‐Enyn‐3‐ones
Authors: Hari Babu Madala , Dwivedi Vikas , Kant Ruchir , Sridhar Reddy Maddi 
Published: February 2015

AbstractConjugated enynes, enol ethers, and enynones are versatile building blocks that can be elaborated by a wide variety of synthetic transformations. The selective synthesis of such units is a prerequisite for their effective utilization. The synthesis of conjugated 2‐phenoxyenynes through a palladium‐catalyzed cross‐addition of terminal alkynes to phenylethynyl ethers (hydroalkynylation) is now presented. The reaction is highly regio‐, stereo‐, and chemoselective, and shows excellent tolerance toward functional groups. The addition further features very mild reaction conditions (room temperature) and an inexpensive catalytic system (without a ligand and with a cheaply available Pd catalyst). The thus synthesized enynyl ethers with allylic hydroxy tethers, which survived the reaction, were shown to be ready precursors for valuable 1‐en‐4‐yn‐3‐ones.
Materialuntersuchungen an Hennigsdorfer Spannstahl aus Brückenbauwerken
Authors: Wilhelm Tobias , Scheerer Silke , Hampel Torsten , Bauer Thomas , Müller Michael 
Published: February 2015

AbstractDer Prozess einer wasserstoffinduzierten Spannungsrisskorrosion (H‐SpRK) ist für Spannbetonbrücken auch 20 Jahre nach gravierenden Schadensfällen im Hochbau weitestgehend unerforscht. Die aktuellen Regelwerke geben eine Hilfestellung zur Vermeidung eines plötzlichen Versagens. Zu Schadensursachen und zum zeitlichen Prozessablauf existiert jedoch nach wie vor keine systematische Datenbasis. Veröffentlichungen zu Ergebnissen von Bauwerksuntersuchungen beschränken sich auf Einzelbauwerke.In diesem Beitrag wird die systematische Erfassung und Auswertung von Bauwerksuntersuchungen an Spannbetonbrücken beschrieben, die mit Spannstahl aus Hennigsdorfer Produktion errichtet wurden, der aktuell als spannungsrisskorrosionsgefährdet eingestuft ist. Grundlage dieser Analyse sind die Ergebnisse von insgesamt 31 Bauwerksuntersuchungen, die in unterschiedlichen Verwaltungsbereichen beauftragt und durchgeführt wurden.Neben der Betrachtung einzelner Kennwerte wird insbesondere auf die Notwendigkeit zur einheitlichen Analyse der Materialkennwerte hingewiesen. Spezielle, nach derzeitiger Vorschriftenlage besonders kritisch einzuschätzende Parameter werden hinsichtlich ihrer Aussagekraft analysiert und Zusammenhänge zwischen einzelnen Parametern bzw. deren möglicher Einfluss auf den Prozess einer H‐SpRK aufgezeigt. Abschließend wird die Einrichtung einer Wissensdatenbank zur einheitlichen Erfassung und Auswertung von Untersuchungsergebnissen angeregt.Material investigations on Hennigsdorfer prestressing steel taken from bridge structuresThere is a knowledge gap of the process of stress cracking corrosion even 20 years after the collapse of buildings as the result of hydrogen embrittlement stress corrosion cracking. The current codes of practice give a support in preventing and early detection of a possible sudden failure. However, there is still no systematic data base to the cause of the corrosion and the time flow of the process. Publications on results of structure investigations are limited to single buildings.In this article the systematic collection and evaluation of structural investigations of prestressed concrete bridges made of steel tendons produced in Hennigsdorf is described. This steel is sensitive to stress corrosion cracking according to the actual knowledge base. Basis of the results is the analysis of 31 bridges, which were assigned from different public administrations.On one side there is the evaluation of single values and on the other side it is pointed to the need for a uniform regulation for the analysis of the material properties. The most critical parameters according to the actual regulations (codes) were be analyzed in terms of their validity. Correlations between individual parameters respectively their possible influence on the process of the stress corrosion cracking was given. Finally, the creation of a knowledge database for the uniform collection and analysis of examination results is suggested.
Stahlbetonfahrbahnplatte aus Fertigteilen mit Ortbetonergänzung beim Ersatzneubau der Straßenbrücke Horsterdamm
Authors: Lühr Stefan , Morgen Karl , Wieser Michael 
Published: February 2015

AbstractDie Straßenbrücke Horsterdamm in Lauenburg kreuzt den Elbe‐Lübeck‐Kanal und die Eisenbahntrasse Lüneburg‐Lübeck. Die alte Straßenbrücke, eine genietete Fachwerkbrücke mit untenliegender Stahlbetonfahrbahn aus dem Jahr 1939, wies erhebliche Schäden auf und musste ersetzt werden. Die neue Brücke wurde als Stabbogenbrücke mit einer Stahlbetonfahrbahn als Verbundkonstruktion geplant und realisiert, wobei zahlreiche Leitungen ein Verschalen auf der Unterseite nahezu unmöglich machten. Zur Realisierung der Fahrbahnplatte wurde daher auf Stahlbetonfertigteile mit Ortbetonergänzung zurückgegriffen. Im Folgenden werden die planerischen und baubetrieblichen Erfahrungen zusammengefasst dargestellt. Abschließend wird auf Vorteile im Hinblick auf Zwangsbeanspruchungen und Erstrissbildung infolge abfließender Hydratationswärmeentwicklung eingegangen.Concrete deck with precast elements and cast in place topping employed at the new road bridge HorsterdammThe new road bridge Horsterdamm in the city of Lauenburg crosses the Elbe‐Lübeck‐Canal and a railway line. The old bridge, a riveted truss bridge, built in 1939, showed severe defects and had to be replaced. The new bridge is designed as an arched bridge with a composite concrete slab. A bunch of pipes and wires under the bridge lead to the decision to employ precast elements with a cast in place topping. The paper deals with some special design aspects and experiences during erection. Special attention is given to the advantages of the precast elements with respect to crack development due to hydration heat and constraint.
Erfahrungen bei Nachrechnung und Verstärkung von Brücken
Authors: Haveresch Karl‐Heinz 
Published: February 2015

AbstractEs wird über die Erfahrungen berichtet, die bei der Nachrechnung und Verstärkung von mehr als 250 älteren Brücken gewonnen wurden. Die Verfahrensschritte, die methodischen und technischen Lösungsansätze sowie die typischen Ergebnisse werden dargestellt und bewertet. Die im Beitrag gegebenen Empfehlungen für die Auslegung und notwendige Ergänzung der Nachrechnungsrichtlinie werden unter dem Vorbehalt einer zukünftigen bauaufsichtlichen Regelung gegeben.Experiences concerning structural assessment and strengthening of older bridgesWhile analysing current traffic volume on German highways, an exceedance of the planned bearing capacity for most of the highway bridges was detected. This exceedance is mainly caused by increasing daily traffic volume, including increasingly heavy trucks with a rising number of axes and load size. In fact, strengthening of most of these bridges becomes necessary to ensure future long‐term serviceability of the German Autobahn system.In the meantime, first experiences in terms of structural assessment and strengthening of older highway bridges were collected. Therefore, this report presents gained experiences concerning the refurbishment of more than 250 older highway bridges. Furthermore, recommendations for application, interpretation and evolution of technical regulations are given. For these purposes process steps, methods of choice and technical solutions are described.
Participant Reflexivity in Community‐Based Participatory Research: Insights from Reflexive Interview, Dialogical Narrative Analysis, and Video Ethnography
Authors: Yang Kyung‐Hwa 
Published: February 2015

AbstractFocusing on researchers, the predominant discourse on reflexivity has seldom considered the contribution that participants could make to research through their self‐reflections. To bring to light the significance of participants' self‐reflection in participatory inquiries, I develop the concept of participant reflexivity, referring to the process in which participants use insights gained through self‐reflection for data analysis and group discussion. My discussion is based on a community‐based participatory research project conducted with a group of adult learners on their educational experiences. I examined the accounts shared by one of the participants by using insights from the theories of reflexive interview, dialogical narrative analysis and video ethnography, and found that her accounts played a pivotal role in evoking group reflections and drawing the conclusion of the project. I argue that participant reflexivity is a useful construct that can do justice to what participants can uniquely offer in participatory inquiries. The concept can also contribute to advancing knowledge of reflexivity by complementing the researcher‐focused predominant discourse on reflexivity. Copyright © 2015 John Wiley & Sons, Ltd.
A Platinum Highly Concave Cube with one Leg on each Vertex as an Advanced Nanocatalyst for Electrocatalytic Applications
Authors: Lai Jianping , Niu Wenxin , Qi Wenjing , Zhao Jianming , Li Suping , Gao Wenyue , Luque Rafael , Xu Guobao 
Published: February 2015

AbstractPlatinum highly concave cubes with one leg on each vertex (HCCLV) enclosed by {7 5 0} facets were conveniently synthesized for the first time through a one‐pot solvothermal method in a mixed solvent of oleylamine and isopropanol containing platinum(II) acetylacetonate. This method can also be extended to the synthesis of Pt dendrite nanocubes at shorter reaction times. Preferential overgrowth may facilitate the formation of Pt HCCLV in the presence of oleylamine and isopropanol. The Pt HCCLV exhibit excellent electrocatalytic activity for the oxidation of methanol (7.76×) and ethanol (5.46×) compared to commercial Pt black. Furthermore, the Pt HCCLV show higher stability than Pt dendrite nanocubes and commercial Pt black. The Pt HCCLV also remarkably improve the electrochemiluminescence activity of the luminol/H2O2 system.
Graphene and Selected Derivatives as Negative Electrodes in Sodium‐ and Lithium‐Ion Batteries
Authors: Pramudita James C. , Pontiroli Daniele , Magnani Giacomo , Gaboardi Mattia , Riccò Mauro , Milanese Chiara , Brand Helen E. A. , Sharma Neeraj 
Published: February 2015

AbstractThe performance of graphene, and a few selected derivatives, was investigated as a negative electrode material in sodium‐ and lithium‐ion batteries. Hydrogenated graphene shows significant improvement in battery performance compared with as‐prepared graphene, with reversible capacities of 488 mA h g−1 for lithium‐ion batteries after 50 cycles and 491 mA h g−1 for sodium‐ion batteries after 20 cycles. Notably, high rates of 1 A g−1 for graphene and 5 A g−1 for hydrogenated graphene indicate higher capacities in sodium‐ion batteries than in lithium‐ion batteries. Alternatively, nickel‐nanoparticle‐decorated graphene performed relatively poorly in lithium‐ion batteries. However, in sodium‐ion batteries they showed the highest reversible capacities of all studied batteries and graphene derivatives, with 826 mA h g−1 after 25 cycles with ≈97 % coulombic efficiency. Overall, minor modifications to graphene can dramatically improve electrochemical performance in both lithium‐ion and sodium‐ion batteries.
Porous Capsules with a Large Number of Active Sites: Nucleation/Growth under Confined Conditions
Authors: Garai Somenath , Rubčić Mirta , Bögge Hartmut , Gouzerh Pierre , Müller Achim 
Published: February 2015

AbstractThis work deals with the generation of large numbers of active sites and with ensuing nucleation/ growth processes on the inside wall of the cavity of porous nanocapsules of the type (pentagon)12(linker)30≡{(MoVI)MoVI5}12{MoV2(ligand)}30. A first example refers to sulfur dioxide capture through displacement of acetate ligands, while the grafted sulfite ligands are able to trap {MoO3H}+ units thereby forming unusual {(O2SO)3MoO3H}5− assemblies. A second example relates to the generation of open coordination sites through release of carbon dioxide upon mild acidification of a carbonate‐type capsule. When the reaction is performed in the presence of heptamolybdate ions, MoO42− ions enter the cavity where they bind to the inside wall while forming new types of polyoxomolybdate architectures, thereby extending the molybdenum oxide skeleton of the capsule. Parallels can be drawn with Mo‐storage proteins and supported MoO3 catalysts, making the results relevant to molybdenum biochemistry and to catalysis.
Visible Light Driven Hydro‐/Deuterodefunctionalization of Anilines
Authors: Majek Michal , Filace Fabiana , Jacobi von Wangelin Axel 
Published: February 2015

AbstractThe defunctionalization of anilines is an important strategy in aromatic‐substitution chemistry. Herein, we report on visible light mediated hydro‐ and deuterodediazonations in solutions of DMF. The mild reaction conditions (DMF, RT, no additives) tolerate various functional groups and allow the site‐specific introduction of D atoms to the arene. Mechanistic investigations indicate the participation of photoredox and radical chain pathways and competing abstraction of methyl and formyl hydrogen atoms from DMF.
Novel Peptide Chemistry in Terrestrial Animals: Natural Luciferin Analogues from the Bioluminescent Earthworm Fridericia heliota
Authors: Dubinnyi Maxim A. , Tsarkova Aleksandra S. , Petushkov Valentin N. , Kaskova Zinaida M , Rodionova Natalja S. , Kovalchuk Sergey I. , Ziganshin Rustam H. , Baranov Mikhail S. , Mineev Konstantin S. , Yampolsky Ilia V. 
Published: February 2015

AbstractWe report isolation and structure elucidation of AsLn5, AsLn7, AsLn11 and AsLn12: novel luciferin analogs from the bioluminescent earthworm Fridericia heliota. They were found to be highly unusual modified peptides, comprising either of the two tyrosine‐derived chromophores, CompX or CompY and a set of amino acids, including threonine, gamma‐aminobutyric acid, homoarginine, and unsymmetrical N,N‐dimethylarginine. These natural compounds represent a unique peptide chemistry found in terrestrial animals and rise novel questions concerning their biosynthetic origin.
ChemInform Abstract: Exceptional Superionic Conductivity in Disordered Sodium Decahydro‐closo‐Decaborate.
Authors: Udovic Terrence J. , et al. et al. 
Published: February 2015

AbstractNa2B10H10 forms a disordered, face centered cubic phase above 360 K with a vacancy‐rich Na+ cation sublattice.
ChemInform Abstract: Preparation, Structural, Thermogravimetric and Spectroscopic Study of Magnesium Potassium Arsenate Hexahydrate.
Authors: Abdija Zuldjevat , Najdoski Metodija , Koleva Violeta , Runcevski Tomce , Dinnebier Robert E. , Soptrajanov Bojan , Stefov Viktor 
Published: February 2015

AbstractMgKAsO4·6H2O is precipitated from an aqueous KOH solution of KH2AsO4 by addition of aqueous MgSO4.
ChemInform Abstract: Ba2PO4I, Sr2PO4I, and Pb2PO4I — A New Structure Type and Three of Its Representatives.
Authors: Haberkorn Robert , Bauer Jessica , Kickelbick Guido 
Published: February 2015

AbstractM2PO4I (M: Pb, Ba, Sr) are prepared via solid state reaction of stoichiometric amounts of M3(PO4)2 and 5% excess MI2 (sealed silica tubes, 600 °C for Pb and Sr compounds, 750 °C for the Ba compound, 6 h).
ChemInform Abstract: Primary Amine Attached to an N‐(Carboxyalkyl)imidazolium Cation: A Recyclable Organocatalyst for the Asymmetric Michael Reaction.
Authors: Kucherenko Alexandr S. , Lisnyak Vladislav G. , Chizhov Alexandr O. , Zlotin Sergei G. 
Published: February 2015

AbstractA novel ionic‐liquid compound tethered with a chiral primary amine is successfully used as recyclable catalyst for the asymmetric Michael reaction of 4‐hydroxy‐2H‐chromen‐2‐one with α,β‐unsaturated ketones.
ChemInform Abstract: Enantioselective Synthesis of Optically Active Bis(β‐hydroxy) Sulfones Through Asymmetric Hydrogenation of Corresponding Ketones Catalyzed by a Chiral Cationic Ruthenium Diamine Catalyst.
Authors: Huang Xiaofei , Zhao Min , Li Naikai , Li Haiyan , Li Jie , Wang Xingwang 
Published: February 2015

AbstractAn efficient asymmetric hydrogenation methodology for the synthesis of various bis(β‐hydroxy)sulfones with excellent diastereo‐ and enantioselectivities is developed.
ChemInform Abstract: Rhodium‐Catalyzed Intramolecular [3 + 2 + 2] Cycloadditions Between Alkylidenecyclopropanes, Alkynes, and Alkenes.
Authors: Araya Marisel , Gulias Moises , Fernandez Israel , Bhargava Gaurav , Castedo Luis , Mascarenas Jose Luis , Lopez Fernando 
Published: February 2015

Abstractleading to 5,7,5‐fused tricyclic systems
ChemInform Abstract: The Diels—Alder Reactions of para‐Benzoquinone Nitrogen‐Derivatives: An Experimental and Theoretical Study.
Authors: Uliana Marciana P. , Servilha Bruno M. , Alexopoulos Olga , de Oliveira Kleber T. , Tormena Claudio F. , Ferreira Marco A. B. , Brocksom Timothy J. 
Published: February 2015

AbstractThe most reactive dienophile is the N‐tosyl derivative, followed by p‐benzoquinone, N‐tosyl‐oxime, and the oxime derivative which does not react in this reaction.
ChemInform Abstract: Methyltrichlorosilane as an Effective Activation Agent for Swern Oxidation.
Authors: Wang Yuanxun , Wang Chao , Sun Jian 
Published: February 2015

AbstractA mild and efficient method for the oxidation of aryl as well as primary and secondary alkyl alcohols using a MeSiCl3‐DMSO system is developed which can be a useful alternative system for the Swern oxidation.
ChemInform Abstract: Iridium‐Catalyzed Isomerization/Bromination of Allylic Alcohols: Synthesis of α‐Bromocarbonyl Compounds.
Authors: Gomez Antonio Bermejo , Erbing Elis , Batuecas Maria , Vazquez‐Romero Ana , Martin‐Matute Belen 
Published: February 2015

AbstractA novel method for the synthesis of α‐bromoketones as single constitutional isomers is developed using an Ir‐catalyzed bromination/isomerization sequence starting from allylic alcohols.
ChemInform Abstract: Transition Metal‐Free Asymmetric and Diastereoselective Allylic Alkylation Using Grignard Reagents: Construction of Vicinal Stereogenic Centers via Kinetic Resolution.
Authors: Grassi David , Alexakis Alexandre 
Published: February 2015

AbstractA transition metal free diastereoselective and enantioselective synthesis leading to compounds with vicinal chiral tertiary or quaternary centers using kinetic resolution is presented.
ChemInform Abstract: Titanocene‐Catalyzed Metallation of Propargylic Acetates in Homopropargyl Alcohol Synthesis.
Authors: Meloche Jennifer L. , Vednor Peter T. , Gianino Joseph B. , Oliver Allen G. , Ashfeld Brandon L. 
Published: February 2015

AbstractThe titanium‐catalyzed metallation using Zn dust and carbonyl addition of propargylic acetates provides homopropargylic alcohols as mixtures of diastereomers.
ChemInform Abstract: Asymmetric Construction of Quaternary Stereocenters by Magnesium Catalyzed Direct Amination of β‐Ketoesters Using in situ Generated Nitrosocarbonyl Compounds as Nitrogen Sources.
Authors: Maji Biplab , Baidya Mahiuddin , Yamamoto Hisashi 
Published: February 2015

AbstractThe asymmetric hydroxyamination of β‐ketoesters with nitrosocarbonyl compounds generated in situ is described.
ChemInform Abstract: Iron‐Mediated Direct Arylation of Unactivated Arenes in Air.
Authors: Huang Yuxing , Moret Marc‐Etienne , Klein Gebbink Robertus J. M. 
Published: February 2015

AbstractIt is demonstrated that a preformed Fe/phen complex catalyzes the direct C‐H arylation with aryl iodides and bromides using excess KOtBu as the base without the use of an inert atmosphere and/or forcing conditions.
ChemInform Abstract: Palladium and TEMPO as Co‐Catalysts in a Desulfinative Homocoupling Reaction.
Authors: Ortgies Dirk H. , Chen Fei , Forgione Pat 
Published: February 2015

AbstractTwo sets of reaction conditions for the oxidative dimerization of aryl sulfinates to symmetrical biaryls using PdCl2 JohnPhos as the catalyst are presented.
ChemInform Abstract: A General Approach to N‐Heterocyclic Carbenes with a Fused Tetracyclic Core: Ligands for Suzuki—Miyaura Cross‐Coupling Reaction.
Authors: Sutar Revannath L. , Kumar Vinod , Shingare Rahul D. , Thorat Shridhar , Gonnade Rajesh , Reddy D. Srinivasa 
Published: February 2015

AbstractThe synthesis of a novel N‐heterocyclic carbene complex composed of a tetracyclic scaffold is disclosed and its usability as a ligand in Pd‐catalyzed Suzuki—Miyaura cross‐coupling reactions is demonstrated.