bluuebunny/crossref_metadata_2025_split huggingface dataset:
Propane Activation by Palladium Complexes with Chelating Bis(NHC) Ligands and Aerobic Cooxidation
Authors: Munz Dominik , Strassner Thomas 
Published: January 2014

AbstractThe development of efficient aerobic oxidation methods remains a challenge for the selective functionalization of CH bonds in alkanes. Herein we report the development of a CH functionalization procedure for propane by using a palladium catalyst with chelating bis(N‐heterocyclic carbene) ligands in trifluoroacetic acid together with a vanadium co‐catalyst. Halides play a decisive role in the reaction. The experimental results are presented together with supporting kinetic data and an isotope effect. The reaction can be run with dioxygen as the oxidant if vanadium salts and halides are present in the reaction mixture. Experimental as well as computational results favor a mechanism involving CH activation by palladium(II), followed by oxidation to palladium(IV) by bromine.
Preparation and properties of hydrophobic poly(vinylidene fluoride)–SiO2 mixed matrix membranes for dissolved oxygen removal from water
Authors: Li Ting , Yu Ping , Luo Yunbai 
Published: January 2014

ABSTRACTThe application of the membrane method for removing dissolved oxygen (DO) from water on the laboratory scale was studied. Flat mixed matrix membranes were composed of poly(vinylidene fluoride) (PVDF) and hydrophobic nanosilica particles, which were used to improve the DO removal process. The SiO2 particles were modified by a silane coupling agent and examined by Fourier transform infrared spectroscopy. It was shown that the surface of the SiO2 particles was bonded to hydrophobic long‐chain alkane groups through chemical bonding. The effects of adding SiO2 particles on the membrane properties and morphology were examined. The results show that the porosity and pore size of the membrane were affected by the introduction of SiO2 particles, and the cross‐sectional morphology of the PVDF composite membranes changed from fingerlike macrovoids to a spongelike structure. The membrane performance of DO removal was evaluated through the membrane unit by a vacuum degassing process. It was found that the SiO2/PVDF hybrid membranes effectively improved the oxygen removal efficiency compared with the original PVDF membranes. The maximum permeation flux was obtained when the loading amount was 2.5 wt %. The effect of the downstream vacuum level was also investigated. The experimental results show that the SiO2/PVDF hybrid membranes had superior performances and could be an alternative membrane for removing DO from water. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40430.
Experimental and numerical study of distortion in flat, L‐shaped, and U‐shaped carbon fiber–epoxy composite parts
Authors: Roozbehjavan Pooneh , Tavakol Behrouz , Ahmed Ashraf , Koushyar Hoda , Das Rony , Joven Ronald , Minaie Bob 
Published: January 2014

ABSTRACTIn this study, flat composite panels were fabricated to find the effect of different manufacturing parameters, including stacking sequence, part thickness, and tooling material, on distortion of carbon fiber‐epoxy composite parts. L‐shaped and U‐shaped panels were also made to investigate the effect of stacking sequence on spring‐in angle and warpage of the curved panels. Results showed that distortion of the flat panels caused by asymmetry in the stacking sequence was an order of magnitude greater than distortion of the panels with an unbalanced stacking sequence; whereas in the curved panels, the panel with an asymmetric stacking sequence showed the least spring‐in angle, and the largest angle was observed in the symmetric panel. MSC Marc was used to predict distortion of the panels, and the simulation results were compared with the experimental results for several stacking sequences of the flat and the L‐shaped panels. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40439.
Flexible and flame‐retardant S‐SEB‐S triblock copolymer/PPE nano‐alloy
Authors: Araki Yoshifumi , Hori Yukari , Suzuki Katsumi , Shirai Hiroshi , Kato Kiyoo , Saito Hiromu 
Published: January 2014

AbstractWe observed that modified polyphenylene ether (PPE) was solubilized in thermoplastic styrenic elastomer (TPS) and that a two‐phase lacy structure formed on nanometer scales when the TPS composition was 67 wt % and modified PPE and polystyrene‐block‐poly(styrene‐co‐ethylene‐co‐butylene)‐block‐polystyrene (S‐SEB‐S triblock copolymer) were blended. However, the molecular weight of the outer PS block segments MoutPS and the content of the outer PS block segments ϕoutPS were <10,000 g/mol and 20 wt %, respectively. The resulting S‐SEB‐S/modified PPE nano‐alloy exhibited both flexibility and flame retardancy, unlike other materials, where a trade‐off exists between these two properties; that is, the flame retardancy was excellent when the phosphorus additive was present. This combination of properties might be attributed to the two‐phase nanometer‐scale structure consisting of flame‐retardant styrene/PPE domains and a continuous soft, lacy SEB matrix. The results for polystyrene‐block‐poly(ethylene‐co‐butylene)‐block‐polystyrene (S‐EB‐S triblock copolymer)/modified PPE blends were presented for comparison. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40446.
Preparation and flocculation behavior of cellulose‐g‐PMOTAC copolymer
Authors: Parviainen Helena , Hiltunen Miia , Maunu Sirkka Liisa 
Published: January 2014

ABSTRACTAs a contribution to the wider use of biodegradable materials, this article reports the synthesis and testing of cationic polyelectrolyte cellulose derivatives for use as flocculation chemicals. Cellulose macroinitiator is synthesized in DMAc/LiCl solvent system by direct acylation of cellulose with 2‐bromoisobutyryl bromide. Cellulose‐graft‐poly(N,N‐dimethyl aminoethyl methacrylate) (cellulose‐g‐PDMAEMA) copolymers are prepared by copper‐mediated radical polymerization in homogeneous medium. Formation of the macroinitiator and graft copolymers is confirmed by ATR‐FTIR and 1H NMR. Quaternization of the graft chains to poly(methacryloxyethyl trimethylammonium chloride) (PMOTAC) produces cellulose‐g‐PMOTAC, which performs similarly to a commercial product in flocculation of pulp and kaolin. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40448.
Effect of TiO2 on morphology and mechanical properties of PVDF/PMMA blend films prepared by melt casting process
Authors: Hosoda Tomonori , Yamada Toshiro 
Published: January 2014

ABSTRACTEffect of titanium dioxide (TiO2) on morphology and mechanical properties of poly(vinylidene fluoride) (PVDF)/poly(methyl methacrylate) (PMMA) blend films prepared at different TiO2 contents by a melt casting process was studied. The results showed that tensile moduli in both the machine direction (MD) and the transverse direction (TD) increased with increasing TiO2 content, and calculated tensile moduli based on the Halpin–Tsai and the Kerner model were consistent with experimental ones in both the MD and TD of films containing 10 wt % TiO2. However, experimental tensile moduli exhibited smaller values compared with calculated ones, as the TiO2 content increased to 30 wt %, and it was assumed that this is due to the decrease of crystallinity of PVDF. Morphological observations indicated that TiO2 particles did not affect crystal structures of PVDF and the morphology of PVDF/PMMA amorphous phase, but hindered the crystallization of PVDF. The MD and TD elongation at break exhibited >200 and <20%, respectively. The SEM micrographs revealed that spherulites could deform along the MD when the tensile force was applied along the direction. By contrast, spherulites could not deform along the TD and fractured at very small elongation, owing to the anisotropic morphology of spherulites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40454.
A Light‐Activated Metal Complex Targets both DNA and RNA in a Fluorescent in Vitro Transcription and Translation Assay
Authors: Heidary David K. , Glazer Edith C. 
Published: January 2014

AbstractA coupled in vitro transcription and translation (IVTT) assay that uses GFP as a fluorescent reporter allowed the potency of a light‐activated cytotoxic ruthenium agent to be quantified. The compound inhibits the function of both DNA and mRNA only upon light activation. The IVTT functional assay provides estimates of potency that are consistent with cellular cytotoxicity values, in marked contrast to the values obtained from traditional DNA‐damage assays.
Nanorods with Biocatalytically Induced Self‐Electrophoresis
Authors: Pavel Ileana‐Alexandra , Bunea Ada‐Ioana , David Sorin , Gáspár Szilveszter 
Published: January 2014

AbstractNanorods with motion enhanced through biocatalytically induced self‐electrophoresis are described. To obtain such nanorods, the polymer half of polypyrrole–gold (PPy‐Au) nanorods is decorated with horseradish peroxidase (HRP) and their metal half with cytochrome c (Cyt c). If such nanorods are suspended in enzymatically generated mixtures of O2⋅− and H2O2, the immobilized Cyt c is reduced by O2⋅−, and the immobilized HRP is oxidized by H2O2. As both hemeproteins are capable of direct electron transfer to/from solid substrates, the oxidized HRP is subsequently reduced with electrons received, through the nanorod, from the reduced Cyt c. The combined processes cause species from the electrical double layer of the nanorods to move from one end of the nanorod to the other, which powers the motion of the nanorods in the opposite direction. The diffusive motion of the hemeprotein‐modified nanorods is characterized by a diffusion coefficient 30 % larger in the presence of O2⋅− and H2O2 than in their absence. Unmodified nanorods do not show such behavior.
ChemInform Abstract: Control of Phase Coexistence in Calcium Tantalate Composite Photocatalysts for Highly Efficient Hydrogen Production.
Authors: Wang Ping , Chen Peirong , Kostka Aleksander , Marschall Roland , Wark Michael 
Published: January 2014

AbstractA series of phase‐controlled and composition‐tuned Ca‐tantalate composite photocatalysts is prepared by adjusting the initial atomic ratio of Ta/Ca precursors from 0.9 to 2.0 using Ca2CO3, Ta2O5, and a 45:55 wt% NaCl/KCl melt flux (corundum crucible, 1123 K, 2 h).
ChemInform Abstract: FeCl3/Pyridine: Dual‐Activation in Opening of Epoxide with Carboxylic Acid under Solvent Free Condition.
Authors: Zhao Yichao , Wang Wen , Li Jian , Wang Feng , Zheng Xiufang , Yun Hongying , Zhao Weili , Dong Xiaochun 
Published: January 2014

AbstractThe title reaction provides a facile approach to various 1,2‐diol monoesters.
ChemInform Abstract: The Reaction of Fullerene C60 with Halogen Azides.
Authors: Dzhemilev Usein M. , Tuktarov Airat R. , Yarullin Ildar R. , Akhmetov Arslan R. 
Published: January 2014

AbstractFirst time, previously unknown 1‐halo‐2‐azidofullerenes are synthesized by reaction of fullerene C60 with halogen azides.
ChemInform Abstract: Metal‐Free Borylative Ring‐Opening of Vinyl Epoxides and Aziridines.
Authors: Sanz Xavier , Lee Graham M. , Pubill‐Ulldemolins Cristina , Bonet Amadeu , Gulyas Henrik , Westcott Stephen A. , Bo Carles , Fernandez Elena 
Published: January 2014

AbstractThe title reaction proceeds with total chemoselectivity towards polyfunctionalized allyl boronates (III), (V), and (VII).
ChemInform Abstract: Two New Naphthoquinone Derivatives from Lysionotus pauciflorus
Authors: Zhong Yu‐Jiao , Wen Qing‐Fa , Li Cong‐Ying , Su Xue‐Hui , Yuan Zhi‐Peng , Li Yan‐Fang 
Published: January 2014

Abstractisolation, structure and cytotoxic activity
2,6‐Bis(arylsulfonyl)anilines as Fluorescent Scaffolds through Intramolecular Hydrogen Bonds: Solid‐State Fluorescence Materials and Turn‐On‐Type Probes Based on Aggregation‐Induced Emission
Authors: Beppu Teruo , Kawata So , Aizawa Naoya , Pu Yong‐Jin , Abe Yasuyuki , Ohba Yoshihiro , Katagiri Hiroshi 
Published: January 2014

AbstractA series of 2,6‐bis[aryl(alkyl)sulfonyl]anilines were synthesized by nucleophilic aromatic substitution of 2,6‐dichloronitrobenzene with various aryl or alkyl thiolates (benzyl‐, phenyl‐, 2‐naphthyl‐, and 2‐aminophenyl thiolate), followed by hydrogenation and subsequent oxidation. All prepared 2,6‐bis[aryl‐(alkyl)sulfonyl]anilines showed high fluorescence emissions in the solid state; X‐ray structures revealed well‐defined intramolecular hydrogen bonds, which served to immobilize the rotatable amino group and generate a fluorescence enhancement in addition to improved photostability. Moreover, absorption and fluorescence spectra showed redshifts in the order of benzyl<phenyl<2‐naphthyl in solution and the solid state, and DFT calculations confirmed charge transfer from the central aniline unit to the side aryl groups through the sulfonyl bridges, which together indicated the push–pull effect with an extended π‐conjugated system comprising the 2,6‐bis(arylsulfonyl)aniline unit. Furthermore, 2,6‐bis(2‐aminophenylsulfonyl)aniline, with rotatable amino groups at the flanking aryl units, was affected by fluorescence quenching in solution. This nonemissive state showed an enhanced environmental sensitivity to solvent polarity and viscosity, along with a “turn‐on” fluorescence response in frozen solvent and in the aggregated form. 2,6‐Bis(2‐aminophenylsulfonyl)aniline behaved as a turn‐on fluorescence probe for selective detection of DNA based on its aggregation‐induced emission.
Near‐IR Sensitization of Dye‐Sensitized Solar Cells Using Thiocyanate‐Free Cyclometalated Ruthenium(II) Complexes Having a Pyridylquinoline Ligand
Authors: Funaki Takashi , Kusama Hitoshi , Onozawa‐Komatsuzaki Nobuko , Kasuga Kazuyuki , Sayama Kazuhiro , Sugihara Hideki 
Published: January 2014

AbstractThree thiocyanate‐free cyclometalated ruthenium(II) complexes, [Ru(dcpq)2(CN)]Cl [where dcpq is 2‐(4′‐carboxypyridin‐2′‐yl)quinoline‐4‐carboxylic acid and C∧N is a bidentate cyclometalating ligand] (compounds FT22, FT23, and FT61), were designed and synthesized as near‐IR (NIR) sensitizers for dye‐sensitized solar cells (DSSCs) to investigate the effect of the ligand structure on the photovoltaic performance. Density functional theory calculations of these complexes show that the highest occupied molecular orbital is mainly localized on the metal center with the C∧N ligand, and the lowest unoccupied molecular orbital is mainly localized on the anchoring dcpq ligand. These complexes exhibit a broad absorption band and superior light‐harvesting properties in the NIR region. FT22‐, FT23‐, and FT61‐based DSSCs exhibit efficiencies of 3.81, 3.43, and 5.53 %, respectively. The modification of the C∧N ligand improves the photovoltaic performance of this class of cyclometalated ruthenium(II) complexes. The DSSC sensitized with FT61 exhibited a 25 % incident photon‐to‐current conversion efficiency at 900 nm.
Antioxidant activity of monooleyl and dioleyl p‐coumarates in in vitro and biological model systems
Authors: Wang Jiankang , Shahidi Fereidoon 
Published: January 2014

Lipase‐catalysed acidolysis of p‐coumaric acid with triolein was carried out, followed by separation of the synthesized phenolipids using column chromatography. The identification of synthesized phenolipids was conducted by using HPLC–MS. The antioxidant activities of the purified phenolipids were assessed in in vitro assays and biological systems. Monooleyl and dioleyl p‐coumarates were identified as the phenolipid species present. The prepared phenolipids exhibited varying antioxidant activities in 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and peroxyl radical scavenging, reducing power, β‐carotene/linoleate bleaching, human low‐density lipoprotein (LDL) cholesterol oxidation as well as hydroxyl and peroxyl radical‐induced DNA cleavage assays.Practical applications: In this study, the antioxidant activity of synthesized phenolipids, monooleyl and dioleyl p‐coumarates obtained from p‐coumaric acid and triolein, was investigated and confirmed in a number of commonly employed assays. The synthesized model phenolipids containing p‐coumaric acid moiety and fatty acid chains exhibited improved lipophilicity and antioxidant activity. Extension of this work to marine omega‐3 oils as starting materials is expected to produce novel phenolipids that may be used as nutraceuticals and functional food ingredients with unique stability characteristics and potentially improved health benefits.
A stabilized finite element formulation for high‐speed inviscid compressible flows using finite calculus
Authors: Kouhi Mohammad , Oñate Eugenio 
Published: January 2014

SUMMARYThis paper aims at the development of a new stabilization formulation based on the finite calculus (FIC) scheme for solving the Euler equations using the Galerkin FEM on unstructured triangular grids. The FIC method is based on expressing the balance of fluxes in a space–time domain of finite size. It is used to prevent the creation of instabilities typically present in numerical solutions due to the high convective terms and sharp gradients. Two stabilization terms, respectively called streamline term and transverse term, are added via the FIC formulation to the original conservative equations in the space–time domain. An explicit fourth‐order Runge–Kutta scheme is implemented to advance the solution in time. The presented numerical test examples for inviscid flows prove the ability of the proposed stabilization technique for providing appropriate solutions especially near shock waves. Although the derived methodology delivers precise results with a nearly coarse mesh, a mesh refinement technique is coupled to the solution process for obtaining a suitable mesh particularly in the high‐gradient zones. Copyright © 2014 John Wiley & Sons, Ltd.
Effects of Nicotine on Proliferation and Survival in Human Umbilical Cord Mesenchymal Stem Cells
Authors: Zeng Hui‐Lan , Qin Yong‐Liang , Chen Hui‐Zhong , Bu Qian‐Qian , Li Yang , Zhong Qi , Han Xin‐Ai , Chen Jie , Yu Pan‐Xi , Liu Ge‐Xiu 
Published: January 2014

ABSTRACTCigarette smoking is known to have negative effects on tissue repair and healing. The aim of this study is to investigate the effects of nicotine in human umbilical cord mesenchymal stem cells (MSCs). After nicotine treatment, MSCs became pyknotic, vacuoles appeared in the cytoplasm and nucleus, and the nuclear boundary became fuzzy as observed using atomic force microscopy. Cell proliferation was inhibited in a dose‐dependent manner (P < 0.05 for all concentrations). The proportion of apoptotic MSCs was significantly increased in a dose‐dependent manner. The mitochondrial membrane potential was significantly decreased (P < 0.05). Nicotine‐treated MSCs had a significantly higher G0/G1 ratio (P < 0.05). Peptide mass fingerprinting identified 27 proteins that were differentially expressed between MSCs with and without nicotine treatment. These nicotine exerted toxic effects on MSCs are likely related, at least in part, to the altered expression of multiple proteins that are essential to the health and proliferation of these cells.
CD40 Signaling Drives B Lymphocytes Into an Intermediate Memory‐Like State, Poised Between Naïve and Plasma Cells
Authors: Upadhyay Mala , Priya G. Krishna , Ramesh P. , Madhavi M.B. , Rath Satyajit , Bal Vineeta , George Anna , Vaidya Tushar 
Published: January 2014

AbstractImmunological memory comprising of antigen‐specific B and T cells contributes to the acquisition of long‐term resistance to pathogens. Interactions between CD40 on B cells and CD40L on T cells are responsible for several aspects of acquired immune responses including generation of memory B cells. In order to gain insights into events leading to memory B cell formation, we analyzed the genome‐wide expression profile of murine naive B cells stimulated in the presence of anti‐CD40. We have identified over 8,000 genes whose expression is altered minimally 1.5‐fold at least at one time point over a 3‐day time course. The array analysis indicates that changes in expression level of maximum number of these genes occur within 24 h of anti‐CD40 treatment. In parallel, we have studied the events following CD40 ligation by examining the expression of known regulators of naive B cell to plasma cell transition, including Pax5 and BLIMP1. The expression profile of these regulatory genes indicates firstly, that CD40 signaling activates naïve B cells to a phenotype that is intermediate between the naive and plasma cell stages of the B cell differentiation. Secondly, the major known regulator of plasma cell differentiation, BLIMP1, gets irreversibly downregulated upon anti‐CD40 treatment. Additionally, our data reveal that CD40 signaling mediated BLIMP1 downregulation occurs by non‐Pax5/non‐Bcl6 dependent mechanisms, indicating novel mechanisms at work that add to the complexity of understanding of B cell master regulatory molecules like BLIMP1 and Pax5. J. Cell. Physiol. 229: 1387–1396, 2014. © 2014 Wiley Periodicals, Inc.
Chain‐end lactonization of polyacrylates prepared by photopolymerization
Authors: Sanai Yasuyuki , Morita Yuki , Asano Youichi , Ishizaki Kenichi , Kubota Kouzou 
Published: January 2014

ABSTRACTThe structural change of the end groups of UV‐cured acrylates with time has been investigated as well as photopolymerization behavior. 2‐Ethylhexyl acrylate, n‐lauryl acrylate, 2‐(2‐ethoxyethoxy)ethyl acrylate, and 2‐ethylhexyl methacrylate were used as a monomer in the current study. In order to mimic industrial conditions, the photopolymerization was conducted with relatively high UV intensity (576 mW/cm2) using a common photoinitiator 1‐hydroxycyclohexyl phenyl ketone. Conversion‐time profile gave a linear first‐order plot suggesting that the steady state was hold throughout the polymerization. Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectra of the resultant polymers indicated the number of the hydroxycyclohexyl chain‐ends decreased with storage time at room temperature. Instead, a lactonic ring appeared to form at the chain‐end by transesterification of the hydroxycyclohexyl group with the ester side chain of the adjacent acrylate according to the results of mass spectrometry and 13C NMR. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1161–1171
Neurally adjusted ventilatory assist (NAVA) in pediatric intensive care—A randomized controlled trial
Authors: Kallio Merja , Peltoniemi Outi , Anttila Eija , Pokka Tytti , Kontiokari Tero 
Published: January 2014

SummaryBackgroundNeurally adjusted ventilatory assist (NAVA) has been shown to improve patient‐ventilator synchrony during invasive ventilation. The aim of this trial was to study NAVA as a primary ventilation mode in pediatric intensive care and to compare it with current standard ventilation modes.MethodsOne hundred seventy pediatric intensive care patients were randomized to conventional ventilation or NAVA. The primary endpoints were time on the ventilator and the amount of sedation needed. To enable comparison between sedative agents, a “sedative unit” was defined for each drug.ResultsThe median time on the ventilator was 3.3 hr in the NAVA group and 6.6 hr in the control group (P = 0.17), and the length of stay in the PICU 49.5 hr in the NAVA group and 72.8 hr in the control group (P = 0.10, per protocol P = 0.03). The amount of sedation needed in the total patient population did not differ between the groups (P = 0.20), but when postoperative patients were excluded (19 vs. 20 patients), the amount was significantly lower in the NAVA group (0.80 vs. 2.23 units/hr, P = 0.03). Lower peak inspiratory pressure and a lower inspired oxygen fraction were found in the NAVA group (P = 0.001 for both). Arterial blood CO2 tensions were slightly higher in the NAVA group up to 32 hr of treatment (P = 0.008). There were no significant differences in the other ventilatory or vital parameters, arterial blood gas values or complications.ConclusionsWe found NAVA to be a safe and feasible primary ventilation mode for use with children. It outscored standard ventilation in some aspects, as it was able to enhance oxygenation even at lower airway pressures and led to reduced use of sedatives during longer periods of treatment. Pediatr Pulmonol. 2015; 50:55–62. © 2014 Wiley Periodicals, Inc.