bluuebunny/crossref_metadata_2025_split huggingface dataset:
N‐Heterocyclic Carbenes Catalyzed Phospho‐Aldol Reaction of Aldehydes
Authors: He Lin , Cai Zhihua , Ma Xiaowei , Du Guangfen 
Published: November 2013

AbstractAn efficient phospho‐aldol reaction of aldehydes catalyzed by N‐heterocyclic carbenes (NHCs) has been developed. With 10 mol% stable NHC 1,3‐bis(2,6‐diisopropylphenyl)imidazol‐2‐ylidene, various aldehydes reacted with dialkylphosphites smoothly to provide α‐hydroxy phosphonates in 59% –99% yield. In this process, NHC was assumed to function as a carbon‐centered br?nsted base.
Elongation of Discotic Liquid Crystal Strands and Lubricant Effects
Authors: Bhattacharyya Surjya Sarathi , Galerne Yves 
Published: December 2013

AbstractAfter a short review on the physics of pulled threads and their mechanical properties, the paper reports and discusses the strand elongation of disordered columnar phases, hexagonal or lamella‐columnar, of small molecules or polymers. The mechanical properties appear to be relevant to the length of the columns of molecules compared to the thread length, instead of the usual correlation length. If, taking the entanglement effect into account, the column length is short, the strand exhibits rather fluid‐like properties that may even look nematic‐like at the macroscopic scale. The Plateau–Rayleigh instability breaks the thread shortly thereafter. However, because the hydrodynamic objects are the columns instead of the molecules, the viscosity is anomalously large. The observations show that the strands in the columnar phases are made of filaments, or fibrils, which are bundles of columns of molecules. This explains the grooves and rings, which are observed on the antenna or bamboo‐like strand profiles. On pulling a strand, the elongation stress eventually exceeds the plasticity threshold, thus breaking the columns and the filaments. As a result, cracks, more exactly, giant dislocations are formed. These change the strand thickness by steps of different birefringence colors. Interestingly, the addition of a solute may drastically change the effective viscosity of the columnar phase and its mechanical properties. Some solutes, such as alkanes, exhibit lubricant and detangling properties, whereas others such as triphenylene, are antilubricant.
Synthesis of 5‐Ethoxymethylfurfural from Fructose and Inulin Catalyzed by a Magnetically Recoverable Acid Catalyst
Authors: Zhang Zehui , Wang Yimei , Fang Zhongfeng , Liu Bing 
Published: November 2013

AbstractA magnetically recoverable catalyst was conveniently synthesized by the immobilization of sulfonic acid on the surface of silica‐encapsulated Fe3O4 nanoparticles, and it was used to catalyze the conversion of fructose‐based carbohydrates into 5‐ethoxymethylfurfural (EMF). A high EMF yield of 89.3 % was obtained from the etherification of 5‐hydroxymethylfurfural at 100 °C for 10 h. The one‐pot conversion of fructose could produce EMF with a yield of 72.5 %. More importantly, EMF was also obtained in a satisfactory yield of 63.3 % when the polysaccharide inulin was used as the starting material. The excellent EMF yield showed that the catalyst had strong and sufficient acidic sites, which were responsible for the good catalytic performance. After the reaction, the catalyst could be readily removed from the reaction mixture by means of an external magnetic field, and the catalyst could be reused several times without significant loss in its catalytic activity. Incidentally, the product EMF was easily obtained through the evaporation of the solvent, ethanol, under reduced pressure at low temperature (ca. 40 °C), and the ethanol could also be reused. The integrated utilization of a biorenewable feedstock, magnetically recoverable catalyst, and bio‐based green solvent is a typical example of an ideal green chemical process to produce potential liquid fuels.
A Randomized Controlled Trial of a Correspondence‐Based Intervention for Carers of Relatives with Psychosis
Authors: Deane Frank P. , Marshall Sarah , Crowe Trevor , White Angela , Kavanagh David 
Published: November 2013

BackgroundFamily members play a crucial role in supporting the recovery of loved ones with psychosis. The journey of recovery is not only traversed by the person experiencing the mental illness but also by their family. Interventions to support these families have traditionally either focused on psychoeducation or addressed problematic interactions or expressed emotion. Family programmes have far less frequently emphasized supporting family members' adjustment to the challenges posed by their relative's disorder or their recovery from associated distress. The study compared a control condition that received only a psychoeducational booklet (Information) and a condition also receiving a correspondence‐based interactive recovery‐oriented intervention (Connections). The Connections group was expected to show greater improvements in recovery knowledge, well‐being, experiences of caregiving, hopefulness and distress.MethodA randomized controlled trial was conducted to evaluate the effectiveness of two correspondence‐based family interventions delivered to 81 carers of relatives with psychosis.ResultsIntent‐to‐treat analyses showed no differential outcomes between conditions, but an analysis of participants who substantially completed their allocated treatment showed that carers receiving Connections had significantly more improvements in well‐being, positive experiences of caregiving and distress.ConclusionsCorrespondence interventions that support carer's recovery may result in more positive mental health for those who complete key elements of the programme compared with information alone. However, many carers do not complete a correspondence programme and this may limit its impact. Copyright © 2013 John Wiley & Sons, Ltd.Key Practitioner Message

A focus on recovery‐oriented interventions holds relevance for carers as well as their loved ones with mental illness.
To our knowledge, this is the first randomized controlled trial of a recovery‐focused intervention for carers.
Carers may receive positive mental health benefits from recovery‐focused correspondence programmes to the extent that they can be encouraged to remain engaged with such programmes.
Analysis of a dual‐resonant multiple split‐ring patch antenna
Authors: Islam M. T. , Ullah M. Habib 
Published: December 2013

SummaryThe design and analysis of a new 0.06λ × 0.09λ compact circular polarized square‐shaped dual‐resonant multiple split‐ring patch antenna on a 1.905‐mm‐thick high‐dielectric ceramic–polytetrafluoroethylene composite is presented. The proposed antenna was designed and analyzed by using a high‐frequency electromagnetic simulator based on the finite element method and was fabricated on a printed circuit board. The measured −10 dB return loss bandwidths were 44.44% (0.7–1.1 GHz) and 34% (2.25–3.1 GHz) at 0.9 and 2.5 GHz center frequencies, respectively. The measured radiation patterns with 5.9 and 4.0 dBi maximum gains were symmetric and steady, making the proposed antenna suitable for radio frequency identification, wireless local area network, wireless body area network, Low Rate‐Wireless Personal Area Network (LR‐WPAN), and so on. The effects of linewidth, dielectric property of the substrate materials, and number of split rings on the return loss were investigated. The surface current distribution over the radiating patch and the characteristics of the Resistance, Inductance, Capacitance (RLC) equivalent circuit of the proposed antenna were also analyzed. Copyright © 2013 John Wiley & Sons, Ltd.
Analysis and efficient provisioning of access networks with correlated and bursty arrivals
Authors: Tian Wenhong 
Published: November 2013

SUMMARYThe statistical multiplexer problem was analyzed extensively in the discrete‐time case within the context of ATM access networks or Internet. Despite the vast literature on ATM multiplexer, this problem has not been satisfactorily analyzed in the continuous‐time case. In this paper, a statistical multiplexer consisting of a single server queue is modeled and analyzed. N identical interrupted Poisson process arrivals flow into the multiplexer are considered, the service time is assumed to be exponentially distributed, and the queue size is infinite. We developed an efficient way to approximate the superposition of n interrupted Poisson process (or n MMPP 2) arrival process by an MMPP 2 through moments and index of dispersion count (IDC) matching. We then find the closed‐form Laplace transform of the departure process of an MMPP 2/M/1 queue. Our results prove that the departure process of an MMPP 2/M/1 queue is not an MMPP 2, which closes the long open problem that whether the departure process of an MMPP/M/1 can be a MMPP. Using Laplace transform matching, we approximated the departure process of an MMPP 2/M/1 by an MMPP 2. These results permit us to analyze a number of statistical multiplexer linked in series as they arise in an access network. Numerical experiments show that approximate analytical results match the simulation results very well. Copyright © 2013 John Wiley & Sons, Ltd.
Noncovalent Chalcogen Bonds and Disulfide Conformational Change in the Cystamine‐Based Hybrid Perovskite [H3N(CH2)2SS(CH2)2NH3]PbIII4
Authors: Louvain Nicolas , Frison Gilles , Dittmer Jens , Legein Christophe , Mercier Nicolas 
Published: December 2013

AbstractThe cystamine‐based hybrid perovskite, α‐[NH3(CH2)2S–S(CH2)2NH3]PbI4 (1a), can be transformed into its polymorph, β‐[NH3(CH2)2S–S(CH2)2NH3]PbI4 (1b), by heat activation (T = 150 °C). The crystal structures have been characterised by single‐crystal X‐ray diffraction, whereas the phase transition was followed by both solid‐state 1H,13C cross‐polarisation magic‐angle spinning (CPMAS) NMR spectroscopy and thermodiffractometry techniques. At 150 °C, compound 1a is transformed into 1b, and, remarkably, the β phase (1b) can be nearly retained down to room temperature, which means that both polymorphs 1a and 1b can coexist over a large temperature range. The structure of 1b has been solved, and it was found that cystamine molecules are disordered over two positions: the two related components with opposite helical conformations. Solid‐state 1H,13C CPMAS NMR spectroscopic measurements show a significant broadening of the NMR spectroscopic line associated with two disordered carbon atoms when cooling 1b from 160 to 50 °C, thereby revealing the presence of exchange between these related atoms, and this favours a molecular dynamical disorder. Disulfide bridges of cystamine molecules are engaged in weak interactions with neighbours, either another cystamine molecule in 1a (SS···SS interactions), or iodine atoms in 1b (SS···I interactions). To evaluate the donating and accepting abilities of the disulfide bridge, and their impact on such weak interactions, a detailed partition of the interaction energy of ten dimer models has been calculated and revealed that the main contribution to the intermolecular bonding comes from the dispersion forces.
Reactivity Consequences of Substituent‐Dependent Preaggregation Motifs of n‐ and tert‐Butyllithium towards 1,3,5‐Triazacyclohexanes
Authors: Hülsmann Matthias , Mix Andreas , Neumann Beate , Stammler Hans‐Georg , Mitzel Norbert W. 
Published: November 2013

AbstractThe cyclic triaminal 1,3,5‐tri‐tert‐butyl‐1,3,5‐triazacyclohexane (TtBuTAC) was treated with tBuLi, but instead of the expected deprotonation at a CH2 unit, the [(TtBuTAC)(tBuLi)] (2) adduct was formed. This is a monomeric tetracoordinate form of tBuLi; its molecular structure was determined by single‐crystal X‐ray diffraction (XRD) and it is likely to be monomeric in C6D6 solution according to 1H NMR, 13C NMR, and 7Li NMR spectroscopy. TtBuTAC reacts with nBuLi to give a laddertype [(TtBuTAC)(nBuLi)2]2 aggregate of four nBuLi units terminated by two TtBuTAC ligands. This adduct was characterized by NMR spectroscopy and XRD. It slowly decays in solution, and minor quantities of a [TtBuTAC‐Li(μ‐nBu)]2[Li3(nBu)2N(tBu)(n‐pent)] product were obtained and characterized by XRD. This compound contains amide units from the reaction of the formal monomer of TtBuTAC, Me3C‐N=CH2, with nBuLi, which demonstrates the different types of reactivity of trisaminals such as TtBuTAC.
Synthesis of Tritium Labelled and Photoactivatable N‐Acyl‐L‐homoserine Lactones: Inter‐Kingdom Signalling Molecules
Authors: Jakubczyk Dorota , Brenner‐Weiss Gerald , Bräse Stefan 
Published: November 2013

AbstractN‐Acyl‐L‐homoserine lactones (AHLs) are signal molecules that are synthesized in nature by Gram‐negative bacteria. They allow communication between bacteria (quorum sensing) and between microorganisms and their eukaryotic host cells (inter‐kingdom signalling). However, very little is known about the mechanisms of the latter system. Therefore, tritium labelled photoactivatable AHLs were synthesized to identify specific receptors in immune cells (e.g., human polymorphonuclear neutrophils, PMN) that bind to AHL. A photoaffinity label – a diazirine group – was chosen as the smallest possible photoactivatable group that can be activated by light irradiation. The resulting highly active carbene will bind covalently to the closest chemical structure in the pocket of the receptor. The diazirine label was introduced into the AHL molecule according to a literature method. To isolate the labelled receptor from the cellular protein moiety, the AHL was additionally labelled with tritium. During the development of an effective isotopic labelling method, a simple route to hydrogen isotope incorporation into the AHLs was proposed and explored in detail. According to the new protocol, the photoactivatable diazirine‐AHL was labelled with deuterium and tritium by a postsynthetic catalytic exchange of the hydrogen with its isotopes, using deuterium or tritium labelled water along with catalytic amounts of metal salts under mild basic conditions.
On the Dienone Motif of Musks: Synthesis and Olfactory Properties of Partially and Fully Hydrogenated Dienone Musks
Authors: Kraft Philip , Jordi Samuel , Denizot Natacha , Felker Irene 
Published: November 2013

AbstractMinimum‐energy calculations and the conformation of the (11Z)‐retinylidium moiety in bovine rhodopsin called into doubt that the function of the dienone motif of a new class of musk odorants 1–6 was to stiffen and planarize the compounds. To investigate the function and importance of these double bonds, the three most potent representatives of the family of dienone musks were partially and fully hydrogenated, and the products were evaluated for their olfactory properties. Stryker's method using the Osborn complex and the procedure of Evans and Fu utilizing catecholborane were used for the reduction of the α,β‐double bonds, palladium on CaCO3 was used for the reduction of the γ,δ‐double bonds, and palladium on charcoal was used for the complete hydrogenation of the dienone systems in 2–4. trans‐Configured cyclopentyl derivatives 23 and 24 were synthesized from 4,4‐dimethylcyclohex‐2‐en‐1‐one by Weitz–Scheffer epoxidation, sodium borohydride reduction, rearrangement to the corresponding carbaldehyde using lithium bromide in toluene/HMPT, cuprate alkylation with the tert‐butyl Gilman reagent, aldol condensation with acetone, and optional hydrogenation with palladium on charcoal. Of the synthesized derivatives, only the γ,δ‐unsaturated enones (i.e., 9, 12, and 15) have a typical musk odor, indicating that the γ,δ‐double bond interacts electronically with the musk receptor(s). As enones 9, 12, and 15 are, however, less intense than the parent compounds (i.e., 2–4), the α,β‐double bond seems to intensify the odor strength due to conformational effects. Conformational effects also seem to favor compounds with an endocyclic γ,δ‐double bond over acyclic dienone systems for their intensity and musk character. In acyclic compounds 10 and 13, the α,β‐double bond introduces violet–orris facets.
Stereospecific Synthesis of γ,δ‐Diamino Esters
Authors: Chin Jik , Kwon Soon Ho , Kim Hyunwoo , Chin Peter , So Soon Mog , Kim B. Moon 
Published: November 2013

Abstractγ,δ‐Diamino acid structural motifs are commonly found in bioactive molecules. We report a one‐pot reaction for the synthesis of γ,δ‐diimino esters with two adjacent chiral centers in enantiomerically pure form through diaza‐Cope rearrangement reaction of diimines formed from (R,R)‐1,2‐bis(2‐hydroxyphenyl)‐1,2‐diaminoethane (hpen) and aldehydes. DFT computation provides interesting insights into the stereospecific rearrangement reaction. The crystal structure of a product diimine formed from the reaction of (R,R)‐hpen and 2,6‐dichlorobenzaldehyde shows that the reaction gives the product diimine in S,S configuration.
A Copper‐Catalyzed One‐Pot, Three‐Component Diastereoselective Synthesis of 3‐Spiroazetidinimine‐2‐oxindoles and Their Synthetic Transformation into Fluorescent Conjugated Indolones
Authors: Periyaraja Somasundharam , Shanmugam Ponnusamy , Mandal Asit Baran 
Published: December 2013

AbstractA facile and efficient copper(I)‐catalyzed one‐pot, three‐component diastereoselective synthesis that provides new 3‐spiroazetidinimine‐2‐oxindoles in excellent yield has been accomplished. The 3‐spiroazetidinimine‐2‐oxindoles underwent a facile ring‐opening reaction of the spiroazetidinimine unit by treatment with KOH/MeOH and p‐thiocresol under basic conditions to afford two new classes of fluorescent conjugated indolones. This method has general applications with regard to the imines that are derived from 9‐fluorenone, 1,2‐diketones, and 1,2,3‐triketones.
Bounding defaults in egress models
Authors: Gwynne Steven M. V. , Kuligowski Erica , Spearpoint Michael , Ronchi Enrico 
Published: November 2013

SummaryEgress model developers are in a difficult position. It is in their interest to develop models that are simplified representations of reality and at the same time reduce inadvertent misuse. While default values enable immediate (i.e. out‐of‐the‐box) use of models without in‐depth familiarization with modelling assumptions, defaults often represent optimistic and/or even unrealistic evacuee behaviours. In this paper, the term ‘default’ relates to a preset, fixed setting or value (or distribution) for a parameter or algorithm. Most egress models provide default values for five core behavioural elements: pre‐evacuation time, travel speeds, route usage, route availability and flow conditions. These behavioural elements typically need to be represented in order for the model to function. The authors suggest that bounding default settings, rather than optimistic values, should be provided for each behavioural element. Here, a bounding default setting is a value derived from relevant empirical data that prolongs the overall evacuation time produced for a particular design. If a user wishes to decrease the conservative nature of a setting, he or she would be required to justify the modification of the bounding default value(s). This approach allows immediate model use but forces the user to modify the settings to obtain credible design scenarios. Copyright © 2013 John Wiley & Sons, Ltd.
Paierdorf ventilation facility – design and construction of a complex structure in challenging ground conditions / Das Lüftungsbauwerk Paierdorf – Planung und Herstellung eines komplexen Untertagebauwerks in anspruchsvollen Gebirgsverhältnissen
Authors: Radoncic Nedim , Hölzl Harald , Moritz Bernd , Bacher Wolfgang 
Published: December 2013

AbstractThe Paierdorf ventilation facility is a part and a preparatory contract for the Koralm Tunnel KAT 3 contract, and is situated approximately 3.7 km from the western portal. It consists of a vertical 120 m deep shaft, an 88 m long expanded section of the south tunnel, access tunnel/TBM entry cavern, an approximately 100 m section in the north tunnel and a ventilation tunnel having a length of around 93 m. The shaft, the access tunnel and the top heading of the south tunnel had already been constructed during the extended exploratory programme of the Koralm Tunnel. The TBM entry cavern, the segment of the north tunnel as well as the section in the south tunnel and the ventilation tunnel were then added in 2012. The ventilation tunnel crosses over the south tunnel with a minimal separation of 2.8 m and connects to the vertical shaft.This geometrical arrangement results in complex geometry of the underground structure and complex geotechnical interaction between the parts. This paper concentrates on the prediction of system behaviour in the design phase with 2D and 3D numerical calculations and the comparison of predicted with observed behaviour during construction.Das Lüftungsbauwerk Paierdorf – Teil des Koralmtunnels und vorgezogenes Baulos zum Hauptbaulos KAT 3 – befindet sich rund 3,7 km vom Westportal entfernt. Es besteht aus einem 120 m tiefen Schacht, einem rund 88 m langen aufzuweitenden Abschnitt in der Südröhre, einem Zugangstunnel bzw. einer TVM‐Einfahrkaverne, einem rund 100 m langen Abschnitt in der Nordröhre und dem ca. 93 m langen Lüftungstunnel. Der Schacht, der Zugangstunnel und die Kalotte der Südröhre wurden bereits während des weiterführenden Erkundungsprogamms errichtet. Die Einfahrkaverne, der Abschnitt in der Nordröhre sowie die Aufweitung in der Südröhre und der Lüftungstunnel wurden im Zuge der Bauarbeiten im Jahr 2012 aufgefahren. Der Lüftungstunnel kreuzt die Südröhre in einem Vertikalabstand von rund 2,8 m und verbindet die Nordröhre mit dem Lüftungsschacht.Die geometrische Anordnung aller Bauwerksteile resultiert in einer komplexen Geometrie und einer komplexen geotechnischen Wechselwirkung zwischen den genannten Teilen. Der Beitrag konzentriert sich auf die Vorhersage des Systemverhaltens in der Planungsphase mittels numerischer 2D‐ und 3D‐FE‐Berechnungen und den Vergleich zwischen dem prognostizierten und beobachteten Verhalten in der Phase der Bauausführung.
The New Semmering Base Tunnel – project overview / Der Semmering‐Basistunnel neu – das Projekt im Überblick
Authors: Gobiet Gerhard 
Published: December 2013

AbstractThe New Semmering Base Tunnel (SBTn) has been designed with a flat gradient to meet the requirement for uniform high‐speed rail infrastructure for the new Südbahn line, which is considered an internationally significant transport corridor for Austria as an industrial location. The 27.3 km tunnel is divided into a number of construction sections with separate contracts due to the geological and hydrogeological conditions. In addition to the tunnel drives from the Gloggnitz portal, the tunnel will also be driven from three intermediate starting points. The individual tunnelling contracts will be started at intervals of about one year. The first tunnelling contract starts in 2014 in the Fröschnitzgraben, the drives in Gloggnitz and the intermediate starting point at Göstritz in 2015 and the tunnel drive in Grautschenhof from 2016. From 2021, when all tunnelling works have been completed and the structure of the two running tunnels has been completed, the installation of the tunnel equipment will start. Opening for service is intended for the end of 2014.Der Semmering‐Basistunnel neu (SBTn) wurde gemäß den Vorgaben zur Bereitstellung einer einheitlich leistungsfähigen Eisenbahninfrastruktur für die neue Südbahn, die als international bedeutende Verkehrsachse für den Wirtschaftsstandort Österreich gilt, mit einer flachen Neigung konzipiert. Der 27,3 km lange Tunnel wird aufgrund der geologischen und hydrogeologischen Verhältnisse sowie der baulogistischen und tunnelbautechnischen Anforderungen in mehreren Bauabschnitten mit unterschiedlichen Baulosen errichtet. Neben den Vortrieben vom Portal Gloggnitz wird der Tunnel über drei Zwischenangriffe aufgefahren. Die einzelnen Tunnelbaulose werden gestaffelt in Abständen von etwa einem Jahr begonnen. Das erste Tunnelbaulos startet 2014 im Fröschnitzgraben, 2015 beginnen die Vortriebe in Gloggnitz und beim Zwischenangriff Göstritz, ab 2016 erfolgt der Tunnelvortrieb in Grautschenhof. Ab 2021, wenn alle Vortriebsarbeiten abgeschlossen und die beiden Tunnelröhren im Rohbau durchgängig fertiggestellt sind, beginnt der Einbau der Tunnelausrüstung. Die Inbetriebnahme ist Ende 2024 vorgesehen.