bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Aqueous Rechargeable Formate‐Based Hydrogen Battery Driven by Heterogeneous Pd Catalysis
Authors: Bi Qing‐Yuan , Lin Jian‐Dong , Liu Yong‐Mei , Du Xian‐Long , Wang Jian‐Qiang , He He‐Yong , Cao Yong 
Published: November 2014

AbstractThe formate‐based rechargeable hydrogen battery (RHB) promises high reversible capacity to meet the need for safe, reliable, and sustainable H2 storage used in fuel cell applications. Described herein is an additive‐free RHB which is based on repetitive cycles operated between aqueous formate dehydrogenation (discharging) and bicarbonate hydrogenation (charging). Key to this truly efficient and durable H2 handling system is the use of highly strained Pd nanoparticles anchored on graphite oxide nanosheets as a robust and efficient solid catalyst, which can facilitate both the discharging and charging processes in a reversible and highly facile manner. Up to six repeated discharging/charging cycles can be performed without noticeable degradation in the storage capacity.
GM‐PHD Filter With Signal Features Of Emitter
Authors: Zhu Youqing , Zhou Shilin 
Published: November 2014

AbstractA new GM‐PHD filter for multiple emitter targets tracking is proposed in this paper. It integrates the signal features of emitter into the process of weights update. In the case of unknowing the distribution of signal features, the FCM algorithm is used for reference to calculate the correlation coefficients between the measurements and candidate targets in place of the likelihoods. Simulation results show that the proposed method can effectively improve the tracking performance in the scenarios with different clutter densities.
Fault Detection for Linear Discrete Time‐varying Systems with Intermittent Observations and Quantization Errors
Authors: Li Yueyang , Liu Shuai , Wang Zhonghua 
Published: November 2014

AbstractThis paper deals with the fault detection (FD) problem for linear discrete time‐varying (LDTV) systems subject to multiple intermittent observations and quantization errors. A set of independent identical distributed random variables are introduced as the indicators of the observation sequences to describe the multiple intermittent measurements. The measured observation is quantized by a logarithmic type quantizer. Our focus is to construct an observer‐based fault detection filter (FDF) to recognize the fault in spite of multiple measurement packet dropouts and quantization inaccuracy. By defining generalized input‐to‐output operators, the FD problem is formulated into a two‐objective optimization framework such that stochastic H∞/H∞ or H−/H∞ performance index is maximized. Probability/indicators‐dependent and probability‐dependent analytical solutions are respectively derived by virtue of an adjoint operator based optimization approach for two cases. One is that the indicators are on‐line known while the other one is that the indicators are not available at each time instant. An illustrative example is employed to demonstrate the effectiveness and applicability of the proposed approach.
A New Model of Networked Control Systems in Robust Control Framework
Authors: Wen Kai , Geng Zhiyong , Zhang Zhenyong , Zhang Lijia 
Published: November 2014

AbstractIn this paper, a new model is proposed to describe networked control systems (NCS) with delays and quantization errors. Firstly, the non‐idealizations are unified in the classic robust control framework and the entire system is modeled as a discrete system closed via a block uncertainty. Then, the stability criteria are derived using small gain theorem, μ tool and integral quadratic constraint (IQC) method, respectively. Finally, a simulation and a numerical example are provided to demonstrate the effectiveness of the proposed methods. This work is supported by the Science Foundation of China University of Petroleum, Beijing (No.YJRC‐2013‐11) and National Natural Science Foundation (NNSF) of China under Grant 61374033.
Trajectory Linearization Control Based Output Tracking Method for Nonlinear Uncertain System Using Linear Extended State Observer
Authors: Xingling Shao , Honglun Wang 
Published: November 2014

AbstractIn this paper, a trajectory linearization control based control law using a linear extended state observer (LESO) is proposed for the output tracking problem of a nonlinear system with uncertainties. First, based on the tracking error dynamics derived by Taylor expansion for the original nonlinear system along the desired trajectory, a feedback linearization (FL) based control law is designed to stabilize a linear time‐varying (LTV) system. To reduce the controller performance sensitive to uncertainties, with partial model information, LESO is constructed to estimate the tracking error vector, as well as the uncertainties in an integrated manner. The closed‐loop stability of the system under the proposed compound scheme is established. Also, simulation results on affine and non‐affine nonlinear uncertain systems are provided to demonstrate the effectiveness of the control strategy. Finally, the issues of sensitivity to sensor noise and the guidelines of tuning parameters are discussed.
Impact of a Stereocentre Inversion in Cyclic Lipodepsipeptides from the Viscosin Group: A Comparative Study of the Viscosinamide and Pseudodesmin Conformation and Self‐Assembly
Authors: Geudens Niels , De Vleeschouwer Matthias , Fehér Krisztina , Rokni‐Zadeh Hassan , Ghequire Maarten G. K. , Madder Annemieke , De Mot René , Martins José C. , Sinnaeve Davy 
Published: November 2014

AbstractThe viscosin group covers a series of cyclic lipodepsipeptides (CLPs) produced by Pseudomonas bacteria, with a range of biological functions and antimicrobial activities. Their oligopeptide moieties are composed of both L‐ and D‐amino acids. Remarkably, the Leu5 amino acid—centrally located in the nonapeptide sequence—is the sole residue found to possess either an L or D configuration, depending on the producing strain. The impact of this D/L switch on the solution conformation was investigated by NMR‐restrained molecular modelling of the epimers pseudodesmin A and viscosinamide A. Although the backbone fold remained unaffected, the D/L switch adjusted the segregation between hydrophobic and hydrophilic residues, and thus the amphipathicity. It also influenced the self‐assembly capacity in organic solvents. Additionally, several new minor variants of viscosinamide A from Pseudomonas fluorescens DR54 were identified, and an NMR assay is proposed to assess the presence of either an L‐ or D‐Leu5.
Pulmonary valvotomy with echocardiographic guidance in neonates with pulmonary atresia and intact ventricular septum
Authors: Hyang Kim Yeo 
Published: November 2014

BackgroundPercutaneous transcatheter valvotomy of the atretic pulmonary valve (PV) carries a risk of perforation of the right ventricle (RV) and requires standby of the cardiac surgical team for potential emergent cardiac management. The objective of this study was to introduce a successful and safe transcatheter wire perforation of the atretic PV using echocardiographic guidance in neonates with pulmonary atresia and an intact ventricular septum.MethodsIn addition to fluoroscopic guidance, echocardiography was used throughout the procedure. For positioning the Judkins right (JR) catheter at the point of ‘tenting’ indicating center of the PV, the morphology and position of the PV were confirmed using a left‐tilted parasternal long axis view and a slight counterclockwise‐rotated parasternal short axis view. After the JR catheter was positioned at the point of tenting of the atretic PV, the stiff end of the 0.014 mm PTCA wire was advanced through the PV toward the main pulmonary artery using echocardiographic guidance. During the first portion of the procedure, accurate perforation using echocardiographic imaging was confirmed. After then, pulmonary valvuloplasty with increasingly larger balloons, beginning with an initial 2.5 × 20 mm2 PTCA balloon and finishing with a final 8 × 20 mm2 PTA balloon was performed.ResultsIn all patients, successful valve perforation and balloon valvuloplasty were achieved. There were no significant cardiac complications, including perforation of the RV.ConclusionsPulmonary valvotomy using transthoracic echocardiographic guidance can reduce the risk of perforation of the RV and be more successful compared with that using only fluoroscopic guidance. © 2014 Wiley Periodicals, Inc.
Synthesis of New Porphyrin–Fullerene Dyads Capable of Forming Charge‐Separated States on a Microsecond Lifetime Scale
Authors: Konev Alexander S. , Khlebnikov Alexander F. , Prolubnikov Pavel I. , Mereshchenko Andrey S. , Povolotskiy Alexey V. , Levin Oleg V. , Hirsch Andreas 
Published: November 2014

AbstractA series of covalently linked axially symmetric porphyrin–fullerene dyads with a rigid pyrrolo[3,4‐c]pyrrolic linker enabling a fixed and orthogonal arrangement of the chromophores has been synthesized and studied by means of transient absorption spectroscopy and cyclic voltammetry. The lifetime of the charge‐separated state has been found to depend on the substituents on the porphyrin core, reaching up to 4 μs for a species with meso‐(p‐MeOC6H4) substituents. The ground and excited electronic states of model compounds have been calculated at the DFT and TD‐DFT B3LYP(6‐31G(d)) levels of theory and analyzed with regard to the effect of the substituent on the stabilization of the charge‐separated state in the porphyrin–fullerene ensemble with a view to explaining the observed dependence.
Synthesis of Phosphorus‐Doped Graphene and its Wide Potential Window in Aqueous Supercapacitors
Authors: Wen Yangyang , Wang Bei , Huang Congcong , Wang Lianzhou , Hulicova‐Jurcakova Denisa 
Published: November 2014

AbstractPhosphorus‐doped (P‐doped) graphene with the P doping level of 1.30 at % was synthesized by annealing the mixture of graphene and phosphoric acid. The presence of P was confirmed by elemental mapping and X‐ray photoelectron spectroscopy, while the morphology of P‐doped graphene was revealed by using scanning electron microscopy and transmission electron microscopy. To investigate the effect of P doping, the electrochemical properties of P‐doped graphene were tested as a supercapacitor electrode in an aqueous electrolyte of 1 M H2SO4. The results showed that doping of P in graphene exhibited significant improvement in terms of specific capacitance and cycling stability, compared with undoped graphene electrode. More interestingly, the P‐doped graphene electrode can survive at a wide voltage window of 1.7 V with only 3 % performance degradation after 5000 cycles at a current density of 5 A g−1, providing a high energy density of 11.64 Wh kg−1 and a high power density of 831 W kg−1.
Stereo‐ and Regioselective Phyllobilane Oxidation in Leaf Homogenates of the Peace Lily (Spathiphyllum wallisii): Hypothetical Endogenous Path to Yellow Chlorophyll Catabolites
Authors: Vergeiner Clemens , Ulrich Markus , Li Chengjie , Liu Xiujun , Müller Thomas , Kräutler Bernhard 
Published: November 2014

AbstractIn senescent leaves, chlorophyll typically is broken down to colorless and essentially photo‐inactive phyllobilanes, which are linear tetrapyrroles classified as “nonfluorescent” chlorophyll catabolites (NCCs) and dioxobilane‐type NCCs (DNCCs). In homogenates of senescent leaves of the tropical evergreen Spathiphyllum wallisii, when left at room temperature and extracted with methanol, the major endogenous, naturally formed NCC was regio‐ and stereoselectively oxidized (in part) to a mixture of its 15‐hydroxy and 15‐methoxy derivative. In the absence of methanol in the extract, only the 15‐OH‐NCC was observed. The endogenous oxidation process depended upon molecular oxygen. It was inhibited by carbon monoxide, as well as by keeping the leaf homogenate and extract at low temperatures. The remarkable “oxidative activity” was inactivated by heating the homogenate for 10 min at 70 °C. Upon addition of a natural epimeric NCC (epiNCC) to the homogenate of senescent or green Sp. wallisii leaves at room temperature, the exogenous epiNCC was oxidized regio‐ and stereoselectively to 15‐OH‐epiNCC and 15‐OMe‐epiNCC. The identical two oxidized epiNCCs were also obtained as products of the oxidation of epiNCC with dicyanodichlorobenzoquinone (DDQ). Water elimination from 15‐OH‐epiNCC occurred readily and gave a known “yellow” chlorophyll catabolite (YCC). The endogenous oxidation process, described here, may represent the elusive natural path from the colorless NCCs to yellow and pink coloured phyllobilins, which were found in (extracts of) some senescent leaves.
Mononuclear Iridium Dinitrogen Complexes Bonded to Zeolite HY
Authors: Yang Dong , Chen Mingyang , Martinez‐Macias Claudia , Dixon David A. , Gates Bruce C. 
Published: November 2014

AbstractThe adsorption of N2 on structurally well‐defined dealuminated HY zeolite‐supported iridium diethylene complexes was investigated. Iridium dinitrogen complexes formed when the sample was exposed to N2 in H2 at 298 K, as shown by infrared spectra recorded with isotopically labeled N2. Four supported species formed in various flowing gases: Ir(N2), Ir(N2)(N2), Ir(C2H5)(N2), and Ir(H)(N2). Their interconversions are summarized in a reaction network, showing, for example, that, in the presence of N2, Ir(N2) was the predominant dinitrogen species at temperatures of 273–373 K. Ir(CO)(N2) formed transiently in flowing CO, and in the presence of H2, rather stable iridium hydride complexes formed. Four structural models of each iridium complex bonded at the acidic sites of the zeolite were employed in a computational investigation, showing that the calculated vibrational frequencies agree well with experiment when full calculations are done at the level of density functional theory, independent of the size of the model of the zeolite.
Proton‐Induced Generation of Remote N‐Heterocyclic Carbene–Ru Complexes
Authors: Fukushima Takashi , Fukuda Ryoichi , Kobayashi Katsuaki , Caramori Giovanni F. , Frenking Gernot , Ehara Masahiro , Tanaka Koji 
Published: November 2014

AbstractThe proton‐induced RuC bond variation, which was previously found to be relevant in the water oxidation, has been investigated by using cyclometalated ruthenium complexes with three phenanthroline (phen) isomers. The designed complexes, [Ru(bpy)2(1,5‐phen)]+ ([2]+), [Ru(bpy)2(1,6‐phen)]+ ([3]+), and [Ru(bpy)2(1,7‐phen)]+ ([4]+) were newly synthesized and their structural and electronic properties were analyzed by various spectroscopy and theoretical protocols. Protonation of [4]+ triggered profound electronic structural change to form remote N‐heterocyclic carbene (rNHC), whereas protonation of [2]+ and [3]+ did not affect their structures. It was found that changes in the electronic structure of phen beyond classical resonance forms control the rNHC behavior. The present study provides new insights into the ligand design of related ruthenium catalysts.
Aggregation‐Induced Emission Rotors: Rational Design and Tunable Stimuli Response
Authors: Li Jie , Zhang Yang , Mei Ju , Lam Jacky W. Y. , Hao Jianhua , Tang Ben Zhong 
Published: November 2014

AbstractA novel molecular design strategy is provided to rationally tune the stimuli response of luminescent materials with aggregation‐induced emission (AIE) characteristics. A series of new AIE‐active molecules (AIE rotors) are prepared by covalently linking different numbers of tetraphenylethene moieties together. Upon gradually increasing the number of rotatable phenyl rings, the sensitivity of the response of the AIE rotors to viscosity and temperature is significantly enhanced. Although the molecular size is further enlarged, the performance is only slightly improved due to slightly increased effective rotors, but with largely increased rotational barriers. Such molecular engineering and experimental results offer more in‐depth insight into the AIE mechanism, namely, restriction of intramolecular rotations. Notably, through this rational design, the AIE rotor with the largest molecular size turns out to be the most viscosensitive luminogen with a viscosity factor of up to 0.98.
Selective and Scalable Synthesis of Trifluoromethanesulfenamides and Fluorinated Unsymmetrical Disulfides using a Shelf‐Stable Electrophilic SCF3 Reagent
Authors: Pluta Roman , Rueping Magnus 
Published: November 2014

AbstractThe chemoselective trifluoromethylthiolation of nitrogen nucleophiles and thiols using N‐(trifluoromethylthio)phthalimide under mild, metal‐free conditions is described. A series of trifluoromethanesulfenamides and unsymmetrical disulfides is prepared from the corresponding aliphatic and aromatic amines and thiols in good yields. The reactions are operationally simple and tolerate a wide variety of functional groups. Trifluoromethanesulfenamides and disulfides belong to interesting classes of organic molecules which possess remarkable properties for medicinal and agrochemical applications.
Regioselective Synthesis of Aurone Derivatives via PBu3‐Catalyzed Cyclization of 2‐Alkynoylphenols
Authors: Liu Changqing , Zhang Zhannan , Zhang Jitan , Liu Xing , Xie Meihua 
Published: November 2014

AbstractAurone derivatives were synthesized in good to high yields by PBu3‐catalyzed intramolecular 5‐exo cyclization of 2‐alkynoylphenols. The reaction proceeds in high regioselectivity without forming 6‐endo cyclization products.
Hydrocyanation of Unsaturated Imines Using Potassium Hexacyanoferrate(II) as a Cyanide Source
Authors: Li Zheng , Wen Fei , Yang Jingya 
Published: November 2014

AbstractAn efficient method for the hydrocyanation of unsaturated imines to synthesize β,γ‐unsaturated α‐aminonitriles by a one‐pot two‐step procedure using potassium hexacyanoferrate(II) as a cyanide source and benzoyl chloride as a promoter under catalyst‐free condition is described. The advantages of this protocol are the use of a nontoxic, nonvolatile and inexpensive cyanating agent, no use of transition metal catalysts, high yield and simple work‐up procedure.
Copper‐Catalyzed Cyanations of Aromatic Bromides with Benzoyl Cyanide
Authors: Wang Liang , Pan Liang , Chen Qun , He Mingyang 
Published: November 2014

AbstractAromatic nitriles were synthesized through copper‐catalyzed cyanations of aromatic bromides using benzoyl cyanide as the cyanide source. A series of functional groups were tolerated under the reaction conditions to provide the products in good yields. Moreover, this protocol avoids using of highly toxic alkali cyanides and expensive palladium catalysts.
Neuroarchitecture and neuroanatomy of the Drosophila central complex: A GAL4‐based dissection of protocerebral bridge neurons and circuits
Authors: Wolff Tanya , Iyer Nirmala A. , Rubin Gerald M. 
Published: November 2014

ABSTRACTInsects exhibit an elaborate repertoire of behaviors in response to environmental stimuli. The central complex plays a key role in combining various modalities of sensory information with an insect's internal state and past experience to select appropriate responses. Progress has been made in understanding the broad spectrum of outputs from the central complex neuropils and circuits involved in numerous behaviors. Many resident neurons have also been identified. However, the specific roles of these intricate structures and the functional connections between them remain largely obscure. Significant gains rely on obtaining a comprehensive catalog of the neurons and associated GAL4 lines that arborize within these brain regions, and on mapping neuronal pathways connecting these structures. To this end, small populations of neurons in the Drosophila melanogaster central complex were stochastically labeled using the multicolor flip‐out technique and a catalog was created of the neurons, their morphologies, trajectories, relative arrangements, and corresponding GAL4 lines. This report focuses on one structure of the central complex, the protocerebral bridge, and identifies just 17 morphologically distinct cell types that arborize in this structure. This work also provides new insights into the anatomical structure of the four components of the central complex and its accessory neuropils. Most strikingly, we found that the protocerebral bridge contains 18 glomeruli, not 16, as previously believed. Revised wiring diagrams that take into account this updated architectural design are presented. This updated map of the Drosophila central complex will facilitate a deeper behavioral and physiological dissection of this sophisticated set of structures. J. Comp. Neurol. 523:997–1037, 2015. © 2014 Wiley Periodicals, Inc.
Semantic client‐side approach for web personalization of SaaS‐based cloud services
Authors: Fan Haolong , Hussain Farookh Khadeer , Hussain Omar Khadeer 
Published: November 2014

SummaryThe demand of software as a service (SaaS)‐based services delivering computing resources as on‐demand software is on the rise in the IT industry. However, one of the drawbacks of the existing SaaS services is that they offer limited or no personalization of the services provided according to the users profile. Personalization as mentioned in the literature has been a key driver in the adoption and usage of various applications and in providing better service experience to the users. However, overwhelming majority of such personalized services rely extensively on the server side, without embracing fast‐developing client‐side technologies. In SaaS‐based cloud services, utilizing this technology is necessary considering their limited processing specifications. Approaches have been proposed in the literature that focus on cloud‐based personalization using client‐side technologies but none of them actually address all the different components that are required for a scalable and holistic personalization framework for SaaS‐based cloud services. In this paper, we address this drawback by proposing a user‐focussed personalization framework. Our proposed framework takes advantage of powerful client side browsers to reduce server overheads, ameliorate performance, establish high intelligence and enrich data processing. To validate and demonstrate the applicability of our framework, we build a prototype model and compare its performance against existing approaches using different metrics. Copyright © 2014 John Wiley & Sons, Ltd.
Toward memory scalability of GYSELA code for extreme scale computers
Authors: Rozar Fabien , Latu Guillaume , Roman Jean , Grandgirard Virginie 
Published: November 2014

SummaryGyrokinetic simulations lead to huge computational needs. Up to now, the Semi‐Lagrangian code GYSELA performed large simulations using up to 65k cores. To understand more accurately the nature of plasma turbulence, finer resolutions are necessary, which make GYSELA a good candidate to exploit the computational power of future extreme scale machines. Among the Exascale challenges, the less memory per core is one of the most critical issues. This paper deals with memory management in order to reduce the memory peak and presents a general method to understand the memory behavior of an application when dealing with very large meshes. This enables us to extrapolate the behavior of GYSELA for expected capabilities of extreme scale machines. Copyright © 2014 John Wiley & Sons, Ltd.
Linear Free‐Energy Relationships between a Single Gas‐Phase Ab Initio Equilibrium Bond Length and Experimental pKaValues in Aqueous Solution
Authors: Alkorta Ibon , Popelier Paul L. A. 
Published: November 2014

AbstractRemarkably simple yet effective linear free energy relationships were discovered between a single ab initio computed bond length in the gas phase and experimental pKavalues in aqueous solution. The formation of these relationships is driven by chemical features such as functional groups,meta/parasubstitution and tautomerism. The high structural content of the ab initio bond length makes a given data set essentially divide itself into high correlation subsets (HCSs). Surprisingly, all molecules in a given high correlation subset share the same conformation in the gas phase. Here we show that accurate pKavalues can be predicted from such HCSs. This is achieved within an accuracy of 0.2 pKaunits for 5 drug molecules.