bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transport and chemical kinetics of H<sub>2</sub>/N<sub>2</sub> jet flame: A flamelet modelling approach with NOx prediction
Authors: Alim MA , Malalasekera W 
Published: February 2009

Â In this work simulation of a turbulent H2/N2 jet diffusion flame with flamelet modelling has been presented. The favre-averaged mixture fraction has been employed to model the combustion. Favre-averaged scalar quantities have been calculated from flamelet libraries by making use of a presumed Probability Density Function (PDF) method. The predicted flame temperature profiles and chemical species concentrations are compared with TNF experimental data obtained from Sandia/California. Predictions considering the unity Lewis number flamelet are found to be in good agreement with temperature and chemical species measurements. Predicted NO results also compared and shown with other species. This study shows that the combustion simulation using unity Lewis number flamelets are effective for predicting the flow, temperature and chemical kinetics of H2/N2 diffusion flame. To account for fluctuations of mixture fraction, its distribution is presumed to have the shape of a beta-function. Keywords: Non-premixed flame, Turbulent Combustion, Flamelet modelling Â doi: 10.3329/jname.v2i1.2028 Journal of Naval Architecture and Marine Engineering 2(1)(2005)33-40
Time‐Dependent Morphology Evolution by Annealing Processes on Polymer:Fullerene Blend Solar Cells
Authors: Jo Jang , Kim Seok‐Soon , Na Seok‐In , Yu Byung‐Kwan , Kim Dong‐Yu 
Published: February 2009

AbstractChanges in the nanoscale morphologies of the blend films of poly (3‐hexylthiophene) (P3HT) and [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM), for high‐performance bulk‐heterojunction (BHJ) solar cells, are compared and investigated for two annealing treatments with different morphology evolution time scales, having special consideration for the diffusion and aggregation of PCBM molecules. An annealing condition with relatively fast diffusion and aggregation of the PCBM molecules during P3HT crystallization results in poor BHJ morphology because of prevention of the formation of the more elongated P3HT crystals. However, an annealing condition, accelerating PCBM diffusion after the formation of a well‐ordered morphology, results in a relatively stable morphology with less destruction of crystalline P3HT. Based on these results, an effective strategy for determining an optimized annealing treatment is suggested that considers the effect of relative kinetics on the crystallization of the components for a blend film with a new BHJ materials pair, upon which BHJ solar cells are based.
Chirality Transfer in Imidazolium Camphorsulfonate Ionic Liquids through Ion Pairing Effects
Authors: Schneiders Karola , Bösmann Andreas , Schulz Peter S. , Wasserscheid Peter 
Published: February 2009

Abstractmagnified imageThe paper describes our studies on ion pair interactions in ionic liquids (IL) using an asymmetric hydrogenation reaction as probe. Three different ionic liquids carrying prochiral keto‐functionalized cations were hydrogenated in the presence of their chiral, enantiomerically pure counter‐ion using an achiral heterogeneous ruthenium catalyst. For the hydrogenation of N‐(3′‐oxobutyl)‐N‐methylimidazolium camphorsulfonate (2), N‐(3′‐oxobutyl)imidazolium camphorsulfonate (4) and N‐(5′‐oxohexyl)‐N‐methylimidazolium camphorsulfonate (6) we found a strong dependency of the enantiomeric excess (ee in the cation) on the polarity of the solvent, the concentration of the IL and the structure of the IL. The highest ee values of up to 94% were found for the hydrogenation of 2 in ethanol. Interestingly, we observed that the ee (and consequently the strength of ion pair interaction) had a pronounced maximum for a certain concentration of the IL in the solvent depending on the nature of the solvent and on the substrate. Remarkably, the concentration leading to the maximum ee could be rationalized by independent determination of the degree of dissociation which was obtained by a combination of diffusion‐ordered NMR spectroscopy and conductivity measurements.
Improved Suzuki–Miyaura Reactions of Aryldiazonium Salts with Boronic Acids by Tuning Palladium on Charcoal Catalyst Properties
Authors: Felpin François‐Xavier , Fouquet Eric , Zakri Cécile 
Published: February 2009

Abstractmagnified imageAn improved Suzuki–Miyaura cross‐coupling reaction of aryldiazonium tetrafluoroborates with boronic acids catalyzed by a highly active palladium catalyst supported on charcoal is described as an extremely practical and efficient protocol. A properties‐activity study of various catalysts clearly established that the optimal catalytic activity was obtained with palladium nanoparticles having a low oxidation degree and uniformly dispersed on the charcoal. The optimized reaction conditions allow the cross‐coupling to proceed at room temperature without any base and ligand in technical grade methanol. Although the catalyst could not be recycled, the low palladium contamination of the solvent and product after a simple filtration of the palladium on charcoal (Pd/C) renders the present protocol competitive and safer for the environment compared to more conventional homogeneous conditions. We have highlighted the efficiency of this novel protocol by a short synthesis of the fungicide Boscalid®.
Novel complement inhibitor limits severity of experimentally myasthenia gravis
Authors: Soltys Jindrich , Kusner Linda L. , Young Andrew , Richmonds Chelliah , Hatala Denise , Gong Bendi , Shanmugavel Vaithesh , Kaminski Henry J. 
Published: February 2009

AbstractObjectiveComplement mediated injury of the neuromuscular junction is considered a primary disease mechanism in human myasthenia gravis and animal models of experimentally acquired myasthenia gravis (EAMG). We utilized active and passive models of EAMG to investigate the efficacy of a novel C5 complement inhibitor rEV576, recombinantly produced protein derived from tick saliva, in moderating disease severity.MethodsStandardized disease severity assessment, serum complement hemolytic activity, serum cytotoxicity, acetylcholine receptor (AChR) antibody concentration, IgG subclassification, and C9 deposition at the neuromuscular junction were used to assess the effect of complement inhibition on EAMG induced by administration of AChR antibody or immunization with purified AChR.ResultsAdministration of rEV576 in passive transfer EAMG limited disease severity as evidenced by 100% survival rate and a low disease severity score. In active EAMG, rats with severe and mild EAMG were protected from worsening of disease and had limited weight loss. Serum complement activity (CH50) in severe and mild EAMG was reduced to undetectable levels during treatment, and C9 deposition at the neuromuscular junction was reduced. Treatment with rEV576 resulted in reduction of toxicity of serum from severe and mild EAMG rats. Levels of total AChR IgG, and IgG2a antibodies were similar, but unexpectedly, the concentration of complement fixing IgG1 antibodies was lower in a group of rEV576‐treated animals, suggesting an effect of rEV576 on cellular immunity.InterpretationInhibition of complement significantly reduced weakness in two models of EAMG. C5 inhibition could prove to be of significant therapeutic value in human myasthenia gravis. Ann Neurol 2009;65:67–75
Brain metabolism in rett syndrome: Age, clinical, and genotype correlations
Authors: Horská Alena , Farage Luciano , Bibat Genila , Nagae Lídia M. , Kaufmann Walter E. , Barker Peter B. , Naidu Sakkubai 
Published: February 2009

AbstractObjectiveBrain metabolism, as studied by magnetic resonance spectroscopy (MRS), has been previously shown to be abnormal in Rett syndrome (RTT). This study reports the relation of MRS findings to age, disease severity, and genotype.MethodsForty RTT girls (1–14 years old) and 12 age‐matched control subjects were examined. Single‐voxel proton MRS of left frontal white matter was performed.ResultsNAA/Cr ratios decreased and myoinositol/Cr ratios increased with age in RTT patients (both p < 0.03), whereas these ratios were stable in control. The mean glutamate and glutamine/Cr ratio was 36% greater in RTT patients than in control (p = 0.043). The mean NAA/Cr ratio was 12.6% lower in RTT patients with seizures compared with those without seizures (p = 0.017). NAA/Cr ratios decreased with increasing clinical severity score (p = 0.031). Compared with patients with T158X, R255X, and R294X mutations, and C‐terminal deletions, patients with the R168X mutation tended to have the greatest severity score (0.01 ≤ p ≤ 0.11) and the lowest NAA/Cr ratio (0.029 ≤ p < 0.14).InterpretationDecreasing NAA/Cr and increasing myoinositol/Cr with age are suggestive of progressive axonal damage and astrocytosis in RTT, respectively, whereas increased glutamate and glutamine/Cr ratio may be secondary to increasing glutamate/glutamine cycling at the synaptic level. The relations between NAA/Cr, presence or absence of seizures, and disease severity suggest that MRS provides a noninvasive measure of cerebral involvement in RTT. Ann Neurol 2009;65:90–97
Translational read‐through of a nonsense mutation in ATP7A impacts treatment outcome in Menkes disease
Authors: Kaler Stephen G. , Tang Jingrong , Donsante Anthony , Kaneski Christine R. 
Published: February 2009

AbstractProtein translation ends when a stop codon in a gene's messenger RNA transcript enters the ribosomal A site. Mutations that create premature stop codons (nonsense mutations) typically cause premature translation termination. An alternative outcome, read‐through translation (or nonsense suppression), is well known in prokaryotic, viral, and yeast genes but has not been clearly documented in humans except in the context of pharmacological manipulations. Here, we identify and characterize native read‐through of a nonsense mutation (R201X) in the human copper transport gene, ATP7A. Western blotting, in vitro expression analyses, immunohistochemistry, and yeast complementation assays using cultured fibroblasts from a classic Menkes disease patient all indicated small amounts of native ATP7AR201X read‐through and were associated with a dramatic clinical response to early copper treatment. Ann Neurol 2009;65:108–113
Sporadic inclusion body myositis: Pathogenic considerations
Authors: Karpati George , O'Ferrall Erin K. 
Published: February 2009

AbstractSporadic inclusion body myositis is the commonest acquired disease of skeletal muscles after 50 years of age, and as such it has commanded a great deal of attention of investigators over the past 25 years. As a result, a large amount of information has accumulated concerning its clinical profile, myopathology, and immunopathology. In the myopathology and immunopathology, there is general agreement that the characteristic features could be divided into a degenerative and an inflammatory group. However, there has been controversy about the possible role of these changes in the pathogenesis of muscle fiber damage. In particular, there is no agreement whether a cause‐and‐effect relationship exists between these two groups of changes, and if so, which is the primary one. In this brief overview, we examine the validity of the various controversial observations and critically review the justification for the two major hypotheses for the primary role of inflammation versus degeneration. Ann Neurol 2009;65:7–11
Zwitterionic Corroles: Regioselective Nucleophilic Pyridination of a Doubly Linked Biscorrole
Authors: Hiroto Satoru , Aratani Naoki , Shibata Naoki , Higuchi Yoshiki , Sasamori Takahiro , Tokitoh Norihiro , Shinokubo Hiroshi , Osuka Atsuhiro 
Published: February 2009

AbstractPyridin greift an: Mit hoher Regioselektivität werden Pyridinderivate nucleophil in der Bucht eines doppelt verbrückten Corrols, das ein stabiles Singulett‐Diradikal ist, unter Bildung zwitterionischer Dimere addiert (siehe Bild, Ar=C6F5). Ladungstransfer zwischen dem anionischen Corrol und den Pyridiniumgruppen bewirkt ein effektives Fluoreszenzlöschen des Corroldimers, das für eine selektive Erkennung von Fluoridionen genutzt werden kann.magnified image
Substituent‐Free Gallium by Hydrogenolysis of Coordinated GaCp*: Synthesis and Structure of Highly Fluxional [Ru2(Ga)(GaCp*)7(H)3]
Authors: Cadenbach Thomas , Gemel Christian , Schmid Rochus , Halbherr Markus , Yusenko Kirill , Cokoja Mirza , Fischer Roland A. 
Published: February 2009

AbstractAll change: Complete ligand exchange through the hydrogenation of [Ru(η4‐cod)(η6‐cot)] in the presence of GaCp* under mild conditions leads to the title complex featuring a “naked” gallium atom bridging two ruthenium centers (see structure: C white, Ga blue, Ru red). This cluster can be considered as a trapped intermediate on the way to mixed‐metal nanoparticles; cot=1,3,5‐cyclooctatriene; cod=1,5‐cyclooctadiene, Cp*=C5Me5.magnified image
Zwitterionic Corroles: Regioselective Nucleophilic Pyridination of a Doubly Linked Biscorrole
Authors: Hiroto Satoru , Aratani Naoki , Shibata Naoki , Higuchi Yoshiki , Sasamori Takahiro , Tokitoh Norihiro , Shinokubo Hiroshi , Osuka Atsuhiro 
Published: February 2009

AbstractPyridine attacks: Nucleophilic addition of pyridine derivatives to a doubly linked corrole, which is a stable singlet biradical species, occurs at the bay area with high regioselectivity to provide zwitterionic dimers (see picture; Ar=C6F5). Charge transfer between the anionic corrole and the pyridinium groups induces effective fluorescence quenching of the corrole dimer, which can be utilized for selective fluoride ion recognition.magnified image
Suboxides with Complex Anions: The Suboxoindate Cs9InO4
Authors: Hoch Constantin , Bender Johannes , Simon Arndt 
Published: February 2009

AbstractSalty metal: In the suboxometallate Cs9InO4, metallic cesium columns (see picture; blue) lie next to ionic oxoindate(III) columns. The chemistry of the suboxides is thus expanded to structures containing complex anions.magnified image
Wireless Activation of Neurons in Brain Slices Using Nanostructured Semiconductor Photoelectrodes
Authors: Zhao Yixin , Larimer Philip , Pressler Richard T. , Strowbridge Ben W. , Burda Clemens 
Published: February 2009

AbstractLight rather than electrical current: The inner or outer surfaces of glass micropipettes can be coated with nanoparticles of a narrow‐band‐gap semiconductor. When visible or near‐infrared light is used for excitation, these micropipettes (labeled PE Stim in the image) can activate nearby neurons (labeled *) in brain tissue without the damage associated with electrical stimulation.magnified image
13C‐NMR study on the structure of phenol‐urea‐formaldehyde resins prepared by methylolureas and phenol
Authors: Fan Dongbin , Chang Jianmin , Li Jianzhang , Mao An , Zhang Lita 
Published: February 2009

AbstractPhenol‐urea‐formaldehyde (PUF) resins were synthesized by reacting mixture of methylolureas (MMU), phenol, and formaldehyde. The structure of PUF cocondensed resins at different stages of reaction were analyzed by liquid 13C nuclear magnetic resonance (NMR) spectroscopy. The liquid 13C‐NMR analysis indicated that methylolureas had the dominant content in MMU with the reaction between urea and formaldehyde under the alkaline condition. The PUF cocondensed resins had no free formaldehyde. methylolureas were well incorporated into the cocondensed resins by reacting with phenolic units to form cocondensed methylene bridges. The second formaldehyde influenced the further reaction and the structure of the PUF resins. The resins with the prepared method of PUFB possessed relatively high degree of polymerization and low proportion of unreacted methylol groups. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Water vapor transmission of poly(ethylene oxide)‐based segmented block copolymers
Authors: Husken D. , Gaymans R. J. 
Published: February 2009

AbstractThis article discusses the rate of water vapor transmission (WVT) through monolithic films of segmented block copolymers based on poly(ethylene oxide) (PEO) and monodisperse crystallisable tetra‐amide segments. The polyether phase consisted of hydrophilic PEO or mixtures of PEO and hydrophobic poly(tetramethylene oxide) (PTMO) segments. The monodisperse tetra‐amide segments (T6T6T) were based on terephthalate units (T) and hexamethylenediamine (6). By using monodisperse T6T6T segments the crystallinity in the copolymers was high (∼ 85%) and, therefore, the amount of noncrystallised T6T6T dissolved in the polyether phase was minimal. The WVT was determined by using the ASTM E96BW method, also known as the inverted cup method. By using this method, there is direct contact between the polymer film and the water in the cup. The WVT experiments were performed in a climate‐controlled chamber at a temperature of 30°C and a relative humidity of 50%. A linear relation was found between the WVT and the reciprocal film thickness of polyether‐T6T6T segmented block copolymers. The WVT of a 25‐μm thick film of PTMO2000‐based copolymers was 3.1 kg m−2 d−1 and for PEO2000‐based copolymers 153 kg m−2 d−1. Of all the studied copolymers, the WVT was linear related to the volume fraction of water absorbed in the copolymer to the second power. The results were explained by the absorption‐diffusion model. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and adsorption performances of novel negatively charged hybrid materials
Authors: Liu Junsheng , Li Tao , Hu Keyan , Shao Guoquan 
Published: February 2009

AbstractA series of novel negatively charged hybrid materials were prepared via sol–gel process and a subsequent epoxide ring‐opening reaction. The coupling reaction was conducted between 3‐glycidoxypropyltrimethoxysilane (GPTMS) and tetraethoxysilane (TEOS), which was confirmed by FTIR spectra. TGA, and DrTGA analyses showed that their thermal stabilities were higher and the optimal molar ratio of GPTMS and TEOS was equal to 1 : 1. The ion‐exchange capacities (IECs) exhibited that they were related to the amount of anionic groups in the hybrid materials, indicating that the negatively charged properties of the hybrid materials could be artificially controlled via the adjustment of silica in these charged hybrid materials. The adsorption properties for Pb2+ and Cu2+ ions revealed that these hybrid materials were able to absorb heavy metal ions, suggesting that they have potential applications in the separation and recovery of environmentally hazardous substances. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Mixed poly(methyl methacrylate)/poly(ethylene glycol) brushes: Study of switching behavior in selective solvent
Authors: Feng Libang , Wang Yanping , Wang Shunhua 
Published: February 2009

AbstractThe mixed polymer brushes composed of two incompatible polymers, poly(methyl methacrylate) and poly(ethylene glycol), were successfully synthesized via a sequential grafting to method, which was confirmed by water‐contact angle and ellipsometric measurements. The resulted mixed polymer brushes could undergo conformational rearrangements upon exposure to different selective solvents, and then the lateral segregation in nonselective solvent and perpendicular segregation in selective solvent happened. As a result, the mixed polymer brushes exhibited the ripple morphology and dimple morphology in corresponding solvent, respectively, and which led to changes in water‐contact angle and surface composition as a function of bulk composition of the mixed polymer brushes. Moreover, the switching properties as the surface composition, wettability and topographical images could occur in a controlled and reversible fashion. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Shrinkage cracking of styrene butadiene polymeric emulsion‐modified concrete using rapid‐hardening cement
Authors: Won J.‐P. , Kim J.‐H. , Park C.‐G. , Kang J.‐W. , Kim H.‐Y. 
Published: February 2009

AbstractThis study was performed to resolve the problem of cracks caused by the rapid hydration heat produced during the early setting stages of rapid‐hardening cement. To address the hydration heat of rapid‐hardening cement, we prepared a modified rapid‐hardening cement using calcium sulfoaluminate clinker combined with a styrene butadiene (SB) polymer. The performance of SB polymeric emulsion‐modified concrete made from modified rapid‐hardening cement was assessed by determining shrinkage (change in length, and plastic and autogenous shrinkage). The modified rapid‐hardening cement in combination with SB polymeric emulsion effectively reduced cracking. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Ionic self‐assembly and characterization of a polysaccharide‐based polyelectrolyte complex of maleic starch half‐ester acid with chitosan
Authors: Xiao Congming , Fang Fang 
Published: February 2009

AbstractA novel polysaccharide‐based polyelectrolyte complex was formed via ionic self‐assembly (ISA) of a carboxylic derivative of starch, maleic starch half‐ester acid (MSA), with chitosan (CS) and precipitated from aqueous solution. Both Fourier transform infrared (FTIR) spectroscopy and elementary analysis results showed that there was CS in the complex. Thermogravimetric analysis (TGA) showed that the thermal resistance of the complex was higher than that of two components and the corresponding blend. X‐ray diffraction (XRD) analysis result revealed that the complex was amorphous, whereas its components were semi‐crystalline. In addition, the drug release behavior of the complex that contains 5‐fluorouracil behaved pH‐responsive. All the experimental results verified the complex was composed of MSA and CS, and also indicated that the driving force for the self‐assembly of the complex was predominantly the electrostatic interactions between two oppositely charged polyelectrolytes, cationic CS, and the anionic MSA. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and characterization of nanostructured and high transparent hydrogel films with pH sensitivity and application
Authors: Yue Yumei , Wang Pixin , Chen Qiang , Guang Liu Xiao 
Published: February 2009

AbstractNovel nanostructured, high transparent, and pH sensitive poly(2‐hydroxyethyl methacrylate‐co‐methacryliac acid)/poly(vinyl alcohol) (P(HEMA‐co‐MA)/PVA) interpenetrating polymer network (IPN) hydrogel films were prepared by precipitation copolymerization of aqueous phase and sequential IPN technology. The first P(HEMA‐co‐MA) network was synthesized in aqueous solution of PVA, then followed by aldol condensation reaction, it formed multiple IPN nanostructured hydrogel film. The film samples were characterized by IR, SEM, DSC, and UV‐vis spectrum. The transmittance arrived at 93%. Swelling and deswelling behaviors showed the multiple IPN nanostuctured film had rapid response. The mechanical properties of all the IPN films improved than that of PVA film. Using crystal violet as a model drug, the release behaviors of the films were studied. The results showed that compared with PVA, which had low drug loading and exhibited high and burst release, the three IPN films had high drug loading and exhibited sustained release. Besides, the release followed different release mechanism at pH = 4.0 and pH = 7.4, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009