bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and spectroelectrochemical investigation of low‐bandgap polymer: Integrated quinoxaline and benzimidazole in one electron acceptor unit
Authors: Mahmut Mamtimin , Awut Tunsagul , Nurulla Ismayil , Mijit Maxhur 
Published: April 2014

ABSTRACTTwo novel π‐conjugated monomers, 6‐(4‐octyloxyphenyl)‐4,8‐bis(thiophene‐2‐yl)‐3H‐[d] imidazole[1,2,5] benzothiadiazole (M3) and 4‐(4‐octyloxyphenyl)‐2,6‐bis(thiophene‐2‐yl)‐3H‐[d] imidazole‐acenaphtho[1,2‐b]quinoxaline (M4), were synthesized. The monomer M4 contains a thiophene electron‐donating unit and electron withdrawing unit in which quinoxaline and benzimidazole integrated in one benzene ring. Electrochemical polymerization of the monomers was carried out in acetonitrile/dichloromethane solvent mixture containing tetra‐n‐butylammonium hexafluorophosphate and electrochromic properties of polymers (P3 and P4) are described in this article. Furthermore, the effects of structural difference on electrochemical redox behavior and spectroelectrochemical properties of the two resulting polymers were examined. The results showed that an anodic wave at +0.48 V versus Ag wire pseudo‐reference electrode corresponding to the monomer M4 oxidation was observed, while one anodic wave at +0.70 V was observed in oxidation of M3 as it contains stronger electron withdrawing thiadiazole structure. The UV‐vis‐Near‐infrared (Near‐infrared spectroscopy) (NIR) spectra analysis revealed that the two polymers have one absorbance band centered at 603 nm. The band gaps, defined as the onset of the absorption band at 603 nm of these polymers, were determined as 1.60 eV for P3 and as 1.55 eV for P4. The electrochromic results showed that P3 revealed about 20% optical contrast at 980 nm and the P4 has 30% optical contrast at 806 nm with low response time (1 s for each polymer). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40861.
Flow injection analysis of thiamazole based on strong Ru(bpy)32+ co‐reactant electrochemiluminescence
Authors: Kong Dexian , Li Qinglu , Jiang Jiang , Xinyu Zheng , Xuechou Zhou , Chi Yuwu , Chen Guonan 
Published: May 2014

AbstractBased on the strong electrochemiluminescence (ECL) reaction between thiamazole and tris(2,2′‐bipyridine)ruthenium(II) (Ru(bpy)32+), a sensitive, simple and rapid flow injection analysis method for the determination of thiamazole was developed. When a Pt working electrode was maintained at a potential of +1.50 V (vs Ag/AgCl) in pH 12.0 H3PO4–NaOH solution containing thiamazole and Ru(bpy)32+ at a flow rate of 1.0 mL/min, a linear range of 2.0 × 10−7–1.0 × 10−4 mol/L with a detection limit of 5.0 × 10−8 mol/L was obtained for the detection of thiamazole. The method showed good reproducibility with a relative standard deviation (RSD) of 0.75%. The method has been successfully applied to the determination of thiamazole in spiked animal feeds. In addition, a co‐reactant ECL mechanism was proposed for the thiamazole–Ru(bpy)32+ system. Copyright © 2014 John Wiley & Sons, Ltd.
Improved protein deproteinization method for the determination of meloxicam in human plasma and application in pharmacokinetic study
Authors: Liew Kai Bin , Loh Gabriel Onn Kit , Tan Yvonne Tze Fung , Peh Kok Khiang 
Published: May 2014

ABSTRACTA simple, rapid, specific and reliable high‐performance liquid chromatographic assay of meloxicam in human plasma has been developed using a C18 reversed‐phase analytical column. Reversed‐phase chromatography was conducted using a mobile phase of 0.02 potassium dihydrogen phosphate (adjusted to pH 2.7 with phosphoric acid)–acetonitrile–triethylamine (35:65:0.05, v/v) with UV detection at 354 nm. The drug in human plasma was deproteinized using a combination of methanol and chloroform. This method is simple, rapid and consistent with a high recovery of meloxicam in human plasma ranging from 93.29 to 111.09%. Regression analysis for the calibration plot for plasma standards obtained for the drug concentrations between (25–4000) ng/mL indicated excellent linearity (r ≥ 0.9997). The proposed method was applied to study the bioequivalence between Mobic (original) and Melocam (generic) products. The study was conducted on using two tablets (4 × 7.5 mg) of each of the commercial product and the reference standard in a two‐way open randomized crossover design involving 20 volunteers. Area under the concentration–time curve, peak concentration (Cmax) and time to reach Cmax were 72,868.61 ng h/mL, 2133.93 ng/mL and 4.06 h for Mobic, and 78,352.52 ng h/mL, 2525.18 ng/mL and 3.61 h for Melocam. Two Cmax were discovered in the pharmacokinetic profiles which confirm enterohepatic recirculation. Copyright © 2014 John Wiley & Sons, Ltd.
Radiation reduction in pediatric and adult congenital patients during cardiac catheterization
Authors: Mauriello Daniel A. , Fetterly Kenneth A. , Lennon Ryan J. , Reeder Guy S. , Taggart Nathaniel W. , Hagler Donald J. , Cetta Frank , Cabalka Allison K. 
Published: April 2014

ObjectivesOur objective was to determine if technical changes combined with radiation safety initiatives reduced the radiation dose delivered to patients during congenital catheterization.BackgroundUse of ionizing radiation is necessary during cardiac catheterization. Minimizing radiation dose, while maintaining clinically useful image quality, is an important safety issue. In our congenital heart center intentional practice changes, including technical changes and provider awareness initiatives, were implemented to decrease radiation dose.MethodsData were retrospectively collected for all procedures involving children and adults with congenital heart disease (CHD) undergoing catheterization over 45 months. Cases were divided into three categories including: noninterventional (NI), simple intervention (SI), and complex intervention (CI). The change in dose was modeled as log of cumulative air kerma (Ka,r). The change in Ka,r was evaluated for each procedural category as well as changes occurring as a function of age and weight.ResultsConsidering all procedures (n = 1,082), Ka,r decreased by 61%. In the NI group (n = 481), Ka,r decreased by 71%. In the SI group (n = 424), Ka,r decreased by 74%. The Ka,r for the 10–17 year old group (n = 125) and those ≥18 years (n = 709) decreased 74 and 67%, respectively. The Ka,r decreased 72 and 66% for those 20–60 kg and ≥60 kg, respectively. Groups not showing significant change in Ka,r included CI, age ≤9 years, and weight ≤20 kg.ConclusionsThrough technical changes and provider awareness initiatives, our institution dramatically reduced the radiation dose in the majority of pediatric and adult CHD patients undergoing cardiac catheterization. © 2014 Wiley Periodicals, Inc.
Effective Separation of Lithium Anode and Sulfur Cathode in Lithium–Sulfur Batteries
Authors: Vizintin Alen , Patel Manu U. M. , Genorio Bostjan , Dominko Robert 
Published: April 2014

AbstractWe demonstrate the importance of effective separation between the sulfur cathode and the lithium anode in Li–S batteries. Improved cycling stability is obtained by using fluoro‐functionalized reduced graphene oxide (rGO) as a separator between the sulfur cathode and the lithium anode. The thickness of the hydrophobic interlayer is found to be 1–2 μm. The possible mechanism is checked with analytical techniques and suggests that improvement in the capacity stability can be attributed to the reduced reactivity of long‐chain polysulfides with the metallic lithium and to the homogenous distribution of end‐discharge products during cycling. The importance of the effective separation of lithium and sulfur is proven by using commercially available lithium conductive ceramics. Good cycling stability over 350 cycles with a coulombic efficiency above 99.95 % is achieved, which demonstrates the possibility of long cycle life with proper separation of lithium and sulfur cathode.
Electrochemically Generated Nanoparticles of Halogen‐Bridged Mixed‐Valence Binuclear Metal Complex Chains
Authors: Martínez‐Periñán Emiliano , Azani Mohammad‐Reza , Abad José M. , Mateo‐Martí Eva , Pariente Félix , Mas‐Ballesté Rubén , Zamora Félix , Lorenzo Encarnación 
Published: April 2014

AbstractSpherical nanoparticles composed of MMX chains can be made by a polymerization strategy driven by electrochemical processes. In particular, the [Pt2(MeCS2)4I2] (MMI2) dimetal subunit is employed as a monomer for the formation of [Pt2(MeCS2)4I]n spherical nanostructures on surfaces. We have paid particular attention to elucidating the general mechanism of the deposition process on the basis of in situ electrochemical measurements. The reduction of MMI2 to give the electrodeposition of nanostructures agrees well with formation of the reduced [MMI2]− species followed by a disproportionation mechanism mediated by iodide anions. The chemical composition of the particles was determined by energy‐dispersive X‐ray spectroscopy (EDX) and X‐ray photoelectron spectroscopy (XPS) to reveal the MMI2 polymer.
Electric Double‐Layer Capacitors Based on Highly Graphitized Nanoporous Carbons Derived from ZIF‐67
Authors: Torad Nagy L. , Salunkhe Rahul R. , Li Yunqi , Hamoudi Hicham , Imura Masataka , Sakka Yoshio , Hu Chi‐Chang , Yamauchi Yusuke 
Published: April 2014

AbstractNanoporous carbons (NPCs) have large specific surface areas, good electrical and thermal conductivity, and both chemical and mechanical stability, which facilitate their use in energy storage device applications. In the present study, highly graphitized NPCs are synthesized by one‐step direct carbonization of cobalt‐containing zeolitic imidazolate framework‐67 (ZIF‐67). After chemical etching, the deposited Co content can be completely removed to prepare pure NPCs with high specific surface area, large pore volume, and intrinsic electrical conductivity (high content of sp2‐bonded carbons). A detailed electrochemical study is performed using cyclic voltammetry and galvanostatic charge–discharge measurements. Our NPC is very promising for efficient electrodes for high‐performance supercapacitor applications. A maximum specific capacitance of 238 F g−1 is observed at a scan rate of 20 mV s−1. This value is very high compared to previous works on carbon‐based electric double layer capacitors.
The Most Stable Isomers of Giant Fullerenes C102 and C104 Captured as Chlorides, C102(603)Cl18/20 and C104(234)Cl16/18/20/22
Authors: Yang Shangfeng , Wang Song , Troyanov Sergey I. 
Published: April 2014

AbstractThe chlorination of HPLC fractions with pristine giant fullerenes, C102 and C104, followed by X‐ray crystallographic study of chlorides, C102(603)Cl18/20 and C104(234)Cl16–22, confirmed the presence of the most stable IPR (IPR=Isolated Pentagon Rule) isomers, C102(603) and C104(234), in the fullerene soot. The discussion concerns the chlorination patterns of polychlorides and relative stability of pristine isomers of C102 and C104 fullerenes.
Deuterium and Hydrogen Tunneling in the Hydrogenation of 4‐Oxocyclohexa‐2,5‐dienylidene
Authors: Henkel Stefan , Ertelt Melanie , Sander Wolfram 
Published: May 2014

Abstract4‐Oxocyclohexa‐2,5‐dienylidene is a highly reactive triplet ground state carbene that is hydrogenated in solid H2, HD, and D2 at temperatures as low as 3 K. The mechanism of the insertion of the carbene into dihydrogen was investigated by IR and EPR spectroscopy and by kinetic studies. H or D atoms were observed as products of the reaction with H2 and D2, respectively, whereas HD produces exclusively D atoms. The hydrogenation shows a very large kinetic isotope effect and remarkable isotope selectivity, as was expected for a tunneling reaction. The experiments, therefore, provide clear evidence for both hydrogen tunneling and the rare deuterium tunneling in an intermolecular reaction.
Semiconducting Clathrates Meet Gas Hydrates: Xe24[Sn136]
Authors: Karttunen Antti J. , Fässler Thomas F. 
Published: April 2014

AbstractSemiconducting Group 14 clathrates are inorganic host–guest materials with a close structural relationship to gas hydrates. Here we utilize this inherent structural relationship to derive a new class of porous semiconductor materials: noble gas filled Group 14 clathrates (Ngx[M136], Ng=Ar, Kr, Xe and M=Si, Ge, Sn). We have carried out high‐level quantum chemical studies using periodic Local‐MP2 (LMP2) and dispersion‐corrected density functional methods (DFT‐B3LYP‐D3) to properly describe the dispersive host–guest interactions. The adsorption of noble gas atoms within clathrate‐II framework turned out to be energetically clearly favorable for several host–guest systems. For the energetically most favorable noble gas filled clathrate, Xe24[Sn136], the adsorption energy is −52 kJ mol−1 per guest atom at the LMP2/TZVPP level of theory, corresponding to −9.2 kJ mol−1 per framework Sn atom. Considering that a hypothetical guest‐free Sn clathrate‐II host framework is only 2.6 kJ mol−1 per Sn atom less stable than diamond‐like α‐Sn, the stabilization resulting from the noble gas adsorption is very significant.
Thermal Mass Flow Measurement of Highly Viscous, Non‐Newtonian Polymers
Authors: Schönteich Bernward , Fischer Fabian , Dilger Klaus 
Published: April 2014

AbstractDie Möglichkeit der auf Konvektion basierenden thermischen Strömungsmessung wird auf ihre Eignung zur Messung von Massenströmen hochviskoser Fluide mit nichtnewtonschen Strömungseigenschaften untersucht. Es wird ein Konzept vorgestellt, wie mit kleinen Sensoren Massenströme gemessen werden können, was neue Möglichkeiten im Bereich der Dosierung und der Strömungsuntersuchung hochviskoser Fluide eröffnet. Die Untersuchungen wurden anhand von Klebstoffen durchgeführt.
Adherence to Dual Antiplatelet Therapy After Coronary Stenting: A Systematic Review
Authors: Czarny Matthew J. , Nathan Ashwin S. , Yeh Robert W. , Mauri Laura 
Published: May 2014

ABSTRACTBackgroundAdherence to dual antiplatelet therapy (DAPT) is critical after coronary stenting. Although adherence rates are frequently assessed in clinical trials, adherence rates in the unselected population recommended for treatment but beyond clinical trials are largely unknown. Therefore, we performed a systematic review of published observational studies to describe rates of DAPT adherence, trends in DAPT use over time, and patient‐level factors associated with nonadherence.HypothesisDAPT adherence declines with increasing time after drug‐eluting stent implantation.MethodsPubMed, Cumulative Index to Nursing and Allied Health Literature, Embase, and Web of Knowledge were searched through November 20, 2012 for studies including patients receiving 1 or more drug‐eluting stents and reporting the use of aspirin and/or thienopyridines, or assessing factors associated with nonadherence to DAPT after bare metal or drug‐eluting stent placement.ResultsWe included 34 studies in the description of DAPT adherence and 11 studies in the description of factors associated with nonadherence. Adherence to DAPT and thienopyridines was high at 1 month but declined by 12 months. Aspirin adherence was at least 90% throughout. Factors associated with nonadherence included bleeding, lower education level, immigrant status, and lack of education regarding DAPT.ConclusionsDAPT adherence is suboptimal at 12 months, and interventions to increase adherence should focus on reducing bleeding risk and improving communication between patients and physicians.
Diversity and wiring variability of visual local neurons in the Drosophila medulla M6 stratum
Authors: Chin An‐Lun , Lin Chih‐Yung , Fu Tsai‐Feng , Dickson Barry J. , Chiang Ann‐Shyn 
Published: April 2014

ABSTRACTLocal neurons in the vertebrate retina are instrumental in transforming visual inputs to extract contrast, motion, and color information and in shaping bipolar‐to‐ganglion cell transmission to the brain. In Drosophila, UV vision is represented by R7 inner photoreceptor neurons that project to the medulla M6 stratum, with relatively little known of this downstream substrate. Here, using R7 terminals as references, we generated a 3D volume model of the M6 stratum, which revealed a retinotopic map for UV representations. Using this volume model as a common 3D framework, we compiled and analyzed the spatial distributions of more than 200 single M6‐specific local neurons (M6‐LNs). Based on the segregation of putative dendrites and axons, these local neurons were classified into two families, directional and nondirectional. Neurotransmitter immunostaining suggested a signal routing model in which some visual information is relayed by directional M6‐LNs from the anterior to the posterior M6 and all visual information is inhibited by a diverse population of nondirectional M6‐LNs covering the entire M6 stratum. Our findings suggest that the Drosophila medulla M6 stratum contains diverse LNs that form repeating functional modules similar to those found in the vertebrate inner plexiform layer. J. Comp. Neurol. 522:3795–3816, 2014. © 2014 Wiley Periodicals, Inc.
Particle‐Size Effects on the Entropy Behavior of a LixFePO4 Electrode
Authors: Kai Kazuhiko , Kobayashi Yo , Miyashiro Hajime , Oyama Gosuke , Nishimura Shin‐ichi , Okubo Masashi , Yamada Atsuo 
Published: April 2014

AbstractThe particle‐size effects on the thermodynamic properties and kinetic behavior of a LixFePO4 electrode have a direct influence on the electrode properties. Thus, the development of high‐performance Li‐ion batteries containing a LixFePO4 cathode requires a complete understanding of the reaction mechanism at the atomic/nano/meso scale. In this work, we report electrochemical calorimetric and potentiometric studies on LixFePO4 electrodes with different particle sizes and clarify the particle‐size effect on the reaction mechanism based on the entropy change of (de)lithiation. Electrochemical calorimetry results show that a reduction in particle size shrinks the miscibility gap of LixFePO4 while potentiometric measurements demonstrate that the LixFePO4 particles equilibrate into either a kinetically metastable state or a thermodynamically stable state depending on the particle size.
Spatially Selective Heteronuclear Multiple‐Quantum Coherence Spectroscopy for Biomolecular NMR Studies
Authors: Sathyamoorthy Bharathwaj , Parish David M. , Montelione Gaetano T. , Xiao Rong , Szyperski Thomas 
Published: April 2014

AbstractSpatially selective heteronuclear multiple‐quantum coherence (SS HMQC) NMR spectroscopy is developed for solution studies of proteins. Due to “time‐staggered” acquisitioning of free induction decays (FIDs) in different slices, SS HMQC allows one to use long delays for longitudinal nuclear spin relaxation at high repetition rates. To also achieve high intrinsic sensitivity, SS HMQC is implemented by combining a single spatially selective 1H excitation pulse with nonselective 1H 180° pulses. High‐quality spectra were obtained within 66 s for a 7.6 kDa uniformly 13C,15N‐labeled protein, and within 45 and 90 s for, respectively, two proteins with molecular weights of 7.5 and 43 kDa, which were uniformly 2H,13C,15N‐labeled, except for having protonated methyl groups of isoleucine, leucine and valine residues.
Interphase Evolution at Two Promising Electrode Materials for Li‐Ion Batteries: LiFePO4 and LiNi1/2Mn1/2O2
Authors: Dupré Nicolas , Cuisinier Marine , Martin Jean‐Frederic , Guyomard Dominique 
Published: April 2014

AbstractThe present review reports the characterization and control of interfacial processes occurring on olivine LiFePO4 and layered LiNi1/2Mn1/2O2, standing here as model compounds, during storage and electrochemical cycling. The formation and evolution of the interphase created by decomposition of the electrolyte is investigated by using spectroscopic tools such as magic‐angle‐spinning nuclear magnetic resonance (7Li, 19F and 31P) and electron energy loss spectroscopy, in parallel to X‐ray photoelectron spectroscopy, to quantitatively describe the interphase and unravel its architecture. The influence of the pristine surface chemistry of the active material is carefully examined. The importance of the chemical history of the surface of the electrode material before any electrochemical cycling and the strong correlation between interface phenomena, the formation/evolution of an interphase, and the electrochemical behavior appear clearly from the use of these combined characterization probes. This approach allows identifying interface aging and failure mechanisms. Different types of surface modifications are then investigated, such as intrinsic modifications upon aging in air or methods based on the use of additives in the electrolyte or carbon coatings on the surface of the active materials. In each case, the species detected on the surface of the materials during storage and cycling are correlated with the electrochemical performance of the modified positive electrodes.
Highlighting the Effects of Co‐eluting Interferences on Compound‐Specific Stable Isotope Analysis of Polycyclic Aromatic Hydrocarbons by Using Comprehensive Two‐Dimensional Gas Chromatography
Authors: Gauchotte‐Lindsay Caroline , McGregor Laura A. , Assal Antoine , Thomas Russell , Kalin Robert M. 
Published: May 2014

AbstractAccuracy is the most important issue when performing compound‐specific stable isotope analysis of polycyclic aromatic hydrocarbons (PAHs) extracted from complex samples. It depends on two main factors: the possible isotopic fractionation of the compounds during extraction and the potential co‐elution with interfering compounds with different isotopic signatures. Herein, a simplified pressurised liquid extraction method for compound‐specific stable isotope analysis of PAHs in non‐aqueous‐phase liquids of coal tar is presented. Samples extracted using the new method and by fractionation on a silica gel column were analysed by comprehensive two‐dimensional gas chromatography. It was possible to evaluate the effect of co‐elution on the carbon and hydrogen stable isotope signatures of the 16 US EPA priority PAHs in coal tars with various proportions of aromatic and aliphatic content. Even in samples that presented a good baseline resolution, the PAHs of interest co‐eluted with other aromatic compounds with a notable effect on their stable isotope values; this demonstrated the necessity to check the quality of all extraction and clean‐up methods (either the simplified pressurised liquid extraction or more traditional labour‐intensive methods) for more complex samples prior to data interpretation. Additionally, comprehensive two‐dimensional gas chromatography enabled visualisation of the suspected co‐elution for the first time.
Aerosol‐Assisted Chemical Vapour Deposition of Transparent Zinc Gallate Films
Authors: Knapp Caroline E. , Manzi Joe A. , Kafizas Andreas , Parkin Ivan P. , Carmalt Claire J. 
Published: April 2014

AbstractAerosol‐assisted chemical vapour deposition (AACVD) reactions of GaMe3, ZnEt2 and the donor‐functionalised alcohol HOCH2CH2OMe (6 equiv.) in toluene resulted in the deposition of amorphous transparent zinc gallate (ZnGa2O4) films at a range of temperatures (350–550 °C). The zinc–gallium oxide films were analyzed by scanning electron microscopy, X‐ray photoelectron spectroscopy (XPS), energy‐dispersive X‐ray analysis, glancing‐angle X‐ray powder diffraction (XRD) and optical studies. The optimum growth temperature was found to be 450 °C, which produced transparent films with excellent coverage of the substrate. XPS confirmed the presence of zinc, gallium and oxygen in the films. Annealing these films at 1000 °C resulted in crystalline films and glancing‐angle powder XRD showed that a zinc gallate spinel framework with a lattice parameter of a=8.336(5) Å was adopted.