bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rheological properties of citrus pectin dispersions and its blends with polyquaternium‐7 and colloidal particles
Authors: Martinez Renata Miliani , Shimojo Andréa Arruda Martins , Santana Maria Helena Andrade 
Published: March 2014

ABSTRACTThis article reports on the rheological behavior of a 5% (w/w) citrus pectin (CP) dispersion, its blends with polyquaternium‐7 (PQ) and also with 200 nm nanoparticles (NP) and 1.8 µm microparticles (MP) of CP. The viscous (G″) and elastic (G′) moduli of the CP dispersion were similar, whereas G′ was higher than G″ for PQ. The 1:20 (w/w) blend of CP and PQ enhanced the viscoelastic profile of CP and also decreased its cross‐over frequency. NP and MP were equally effective in enhancing the viscoelastic properties of CP. The best viscoelastic behavior was obtained with 1:20:0.4 (w/w) CP:PQ:(NP or MP) composition. The association of CP with PQ and/or MP or NP tended to change the behavior of CP and PQ dispersions from pseudoplastic to Newtonian. Cox‐Merz superposition was observed for CP:PQ and CP:(MP or NP). These findings contribute for modulation of the rheological properties of CP dispersions for specific applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40583.
Carbon fibers derived from UV‐assisted stabilization of wet‐spun polyacrylonitrile fibers
Authors: Morales Marlon S. , Ogale Amod A. 
Published: March 2014

ABSTRACTA rapid, dual‐stabilization route for the production of carbon fibers from polyacrylonitrile (PAN) precursor fibers is reported. A photoinitiator, 4,4′‐bis(diethylamino)benzophenone, was added to PAN solution before the fiber wet‐spinning step. After a short UV treatment that induced cyclization and crosslinking at a lower temperature, precursor fibers could be rapidly thermo‐oxidatively stabilized and successfully carbonized. Scanning electron microscopy micrographs show no deterioration of the microstructure or hollow‐core formation in the fibers due to UV treatment or presence of photoinitiator. Fast‐thermally stabilized pure PAN‐based carbon fibers show hollow‐core fiber defects due to inadequate thermal stabilization, but such defects were not observed in carbon fibers derived from fast‐thermally stabilized fibers that contained photoinitiator and were UV treated. Tensile testing results confirm that fibers containing 1 wt % photoinitiator and UV treated for 5 min display higher tensile modulus than all other sets of thermally stabilized and carbonized fibers. Wide‐angle X‐ray diffraction results show a higher development of the aromatic structure and molecular orientation in thermally stabilized fibers. No significant increase in interplanar spacing or decrease in crystals size were observed within the UV‐stabilized carbon fibers containing photoinitiator, but such fibers retain a higher extent of molecular orientation when compared with control fibers. These results establish for the first time, the positive effect of the external addition of photoinitiator and UV treatment on the properties of the PAN‐based fibers, and may be used to reduce the precursor stabilization time for faster carbon fiber production rate. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40623.
Cytocompatible and regenerable antimicrobial cellulose modified by N‐halamine triazine ring
Authors: Ma Kaikai , Xie Zhiwei , Jiang Qianyuan , Li Jing , Li Rong , Ren Xuehong , Huang Tung‐Shi , Zhang Ke‐Qin 
Published: March 2014

ABSTRACTThis study reports the formation of cyanuric chloride hydrolysate and its attachment onto cellulose fibers though covalent bonding. The hydrolysis product, 2,4‐dichloro‐6‐hydroxy‐1,3,5‐triazine, is prepared in water solution at ambient temperature, and directly used as a treatment solution for the treatment of cotton fabrics without any prior work‐up. The triazine treated fabrics are rendered antimicrobial through exposure to chlorine bleach. The oxidative chlorine bonded to the triazine‐treated cotton is very stable and regenerable to standard washing tests and UVA irradiation test. The N‐halamine modified cotton fabrics demonstrate excellent antimicrobial efficacy against Staphylococcus aureus ATCC 6538 and Escherichia coli O157:H7 ATCC 43895 with 7‐logs reductions within the contact time of 10 and 5 min, respectively. In addition, the results of in vitro cell viability test suggested that the N‐halamine modified fabrics have excellent cytocompatibility to mammalian cells. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40627.
A Fluorescent Polymeric Quantum Dot/Aptamer Superstructure and Its Application for Imaging of Cancer Cells
Authors: Jie Guifen , Zhao Yanbin , Qin Yingqiang 
Published: March 2014

AbstractIn this work, a novel polymeric quantum dot/aptamer superstructure with a highly intense fluorescence was fabricated by a molecular engineering strategy and successfully applied to fluorescence imaging of cancer cells. The polymeric superstructure, which is composed of both multiple cell‐based aptamers and a high ratio of quantum dot (QD)‐labeled DNA, exploits the target recognition capability of the aptamer, an enhanced cell internalization through multivalent effects, and cellular disruption by the polymeric conjugate. Importantly, the polymeric superstructure exhibits an increasingly enhanced fluorescence with recording time and is thus suitable for long‐term fluorescent cellular imaging. The unique and excellent fluorescence property of the QD superstructure paves the way for developing polymeric QD superstructures that hold promise for applications such as in vivo imaging.
Role of trace elements (Zn, Sr, Fe) in bone development: Energy dispersive X‐ray fluorescence study of rat bone and tooth tissue
Authors: Maciejewska Karina , Drzazga Zofia , Kaszuba Michał 
Published: March 2014

AbstractOsteoporosis is one of the most common debilitating disease around the world and it is more and more established among young people. There are well known recommendations for nutrition of newborns and children concerning adequate calcium and vitamin D intake in order to maintain proper bone density. Nevertheless, important role in structure and function of a healthy bone tissue is played by an integration between all constituents including elements other than Ca, like trace elements, which control vital processes in bone tissue. It is important from scientific point of view as well as prevention of bone diseases, to monitor the mineralization process considering changes of the concentration of minerals during first stage of bone formation. This work presents studies of trace element (zinc, strontium, and iron) concentration in bones and teeth of Wistar rats at the age of 7, 14, and 28 days. Energy dispersive X‐ray fluorescence (EDXRF) was used to examine mandibles, skulls, femurs, tibiae, and incisors. The quantitative analysis was performed using fundamental parameters method (FP). Zn and Sr concentrations were highest for the youngest individuals and decreased with age of rats, while Fe content was stable in bone matrix for most studied bones. Our results reveal the necessity of monitoring concentration of not only major, but also minor elements, because the trace elements play special role in the first period of bone development. © 2014 BioFactors, 40(4):425–435, 2014
Defined Conjugation of Glycans to the Lysines of CRM197 Guided by their Reactivity Mapping
Authors: Crotti Stefano , Zhai Huili , Zhou Jing , Allan Martin , Proietti Daniela , Pansegrau Werner , Hu Qi‐Ying , Berti Francesco , Adamo Roberto 
Published: March 2014

AbstractSystematic characterisation of the reactivity of the lysine moieties in CRM197 towards N‐hydroxysuccinimide linkers bearing alkynes or azides is described. This involves two‐step conjugation of various glycans to CRM197 by click chemistry in a well‐defined manner. By semiquantitative LC‐MS/MS analysis of proteolytic digests of the conjugates formed, the reactivity of lysine residues in the protein was mapped and ranked. Computational analysis of the solvent accessibility of each lysine residue (based on the CRM197 crystal structure) established a correlation between reactivity and surface exposure. By this approach, conjugation involving lysine residues (normally a random process) can be controlled. It enables the preparation of lysine‐mediated glycoconjugates with improved batch‐to‐batch reproducibility, thereby producing neo‐glycoconjugates with more‐consistent biological activity.
Rapid Total Synthesis of DARPin pE59 and Barnase
Authors: Mong Surin K. , Vinogradov Alexander A. , Simon Mark D. , Pentelute Bradley L. 
Published: March 2014

AbstractWe report the convergent total synthesis of two proteins: DARPin pE59 and Bacillus amyloliquefaciens RNase (Barnase). Leveraging our recently developed fast‐flow peptide‐synthesis platform, we rapidly explored numerous conditions for the assembly of long polypeptides, and were able to mitigate common side reactions, including deletion and aspartimide products. We report general strategies for improving the synthetic quality of difficult peptide sequences with our system. High‐quality protein fragments produced under optimal synthetic conditions were subjected to convergent native chemical ligation, which afforded native full‐length proteins after a final desulfurization step. Both DARPin and Barnase were folded and found to be as active as their recombinant analogues.
Regiocontroled Palladium‐Catalysed Direct Arylation at Carbon C2 of Benzofurans using Benzenesulfonyl Chlorides as the Coupling Partners
Authors: Loukotova Lenka , Yuan Kedong , Doucet Henri 
Published: March 2014

AbstractThe regioselective palladium‐catalysed direct arylation of benzofurans with aryl halides is a challenging reaction because carbons C2 and C3 display similar reactivity. Such couplings generally lead to mixtures of C2 and C3 arylation products together with C2,C3 diarylation products. We found that the use of benzenesulfonyl chlorides instead of aryl halides as the coupling partner allows for controlling the regioselectivity of the palladium‐catalysed arylation of benzofurans in favour of carbon C2. This method tolerates a variety of substituents on the benzenesulfonyl derivative.
Platinum–Rhenium Synergy on Reducible Oxide Supports in Aqueous‐Phase Glycerol Reforming
Authors: Ciftci Aysegul , Eren Seda , Ligthart D. A. J. Michel , Hensen Emiel J. M. 
Published: March 2014

AbstractA significant support effect was observed for the aqueous‐phase reforming (APR) of glycerol over a series of Pt‐ and PtRe‐loaded ceria‐, ceria–zirconia‐, zirconia‐, and titania‐supported catalysts. Glycerol conversion rates decreased in the order Pt/TiO2>Pt/ZrO2>Pt/CeZrO2>Pt/CeO2. Upon addition of Re, APR activities of all the Pt catalysts increased. Re promotion for glycerol APR was strongest for PtRe/CeO2. Pt/CeO2 was least active because of the incomplete reduction of Pt. Pt was more easily reduced in PtRe/CeO2 because of the strong Pt–Re interaction. On comparison with previous data on Pt/C and PtRe/C, the oxide‐supported catalysts were more active in the WGS reaction, with the titania‐supported catalyst as the most active, which was a result of the activation of water on the titania support. The acidity of these groups also resulted in increased CO cleavage rates of Pt/TiO2 relative to the rates of Pt/C in APR. A more detailed comparison of Pt(Re)/C and Pt(Re)/TiO2 is made. Monitoring acetaldehyde decomposition to determine the rate of CC bond cleavage evidenced a strong promoting effect of Re on the supported Pt catalysts. All catalysts produced carbon monoxide, methane, and ethanol during acetaldehyde decomposition; notably, Pt(Re)/TiO2 also formed products such as ethylene, ethane, propylene, and propane, indicative of a mechanism also involving ethanol dehydration and olefin coupling to CHx surface intermediates derived from acetaldehyde. The activity in overall glycerol conversion in APR decreased in the order PtRe/C>PtRe/TiO2>Pt/TiO2>Pt/C.
Manganese‐Corrole Complexes as Versatile Catalysts for the Ring‐Opening Homo‐ and Co‐Polymerization of Epoxide
Authors: Robert Carine , Ohkawara Takahiro , Nozaki Kyoko 
Published: March 2014

AbstractManganese‐corrole complexes in combination with a co‐catalyst [PPN]X ([PPN]+=bis(triphenylphosphoranylidene)iminium) were found to be new versatile catalysts for the polymerization of epoxides, copolymerization of epoxides with CO2, and copolymerization of epoxides with cyclic anhydrides affording a wide range of polymeric materials. This work should allow the synthesis of new types of improved innovative (co)polymers with original properties and would clearly increase the number of applications for polyesters, polycarbonates, and polyethers.
Ruthenium/Imidazolylphosphine Catalysis: Hydrogenation of Aliphatic and Aromatic Nitriles to Form Amines
Authors: Werkmeister Svenja , Junge Kathrin , Wendt Bianca , Spannenberg Anke , Jiao Haijun , Bornschein Christoph , Beller Matthias 
Published: March 2014

AbstractA convenient and efficient catalyst system for the hydrogenation of aliphatic nitriles towards the corresponding primary amines in high to excellent yields is presented. In addition, aromatic nitriles are reduced smoothly, too. The use of low catalyst loadings and molecular hydrogen make this protocol an attractive methodology.
Stereoselective Rhodium‐Catalysed [2+2+2] Cycloaddition of Linear Allene–Ene/Yne–Allene Substrates: Reactivity and Theoretical Mechanistic Studies
Authors: Haraburda Ewelina , Torres Òscar , Parella Teodor , Solà Miquel , Pla‐Quintana Anna 
Published: March 2014

AbstractAllene–ene–allene (2 and 5) and allene–yne–allene (3 and 7) N‐tosyl and O‐linked substrates were satisfactorily synthesised. The [2+2+2] cycloaddition reaction catalysed by the Wilkinson catalyst [RhCl(PPh3)3] was evaluated. Substrates 2 and 5, which bear a double bond in the central position, gave a tricyclic structure in a reaction in which four contiguous stereogenic centres were formed as a single diastereomer. The reaction of substrates 3 and 7, which bear a triple bond in the central position, gave a tricyclic structure with a cyclohexenic ring core, again in a diastereoselective manner. All cycloadducts were formed by a regioselective reaction of the inner allene double bond and, therefore, feature an exocyclic diene motif. A Diels–Alder reaction on N‐tosyl linked cycloadducts 8 and 10 allowed pentacyclic scaffolds to be diastereoselectively constructed. The reactivity of the allenes on [2+2+2] cycloaddition reactions was studied for the first time by density functional theory calculations. This mechanistic study rationalizes the order in which the unsaturations take part in the catalytic cycle, the reactivity of the two double bonds of the allene towards the [2+2+2] cycloaddition reaction, and the diastereoselectivity of the reaction.
Out‐of‐Water Constitutional Self‐Organization of Chitosan–Cinnamaldehyde Dynagels
Authors: Marin Luminita , Moraru Simona , Popescu Maria‐Cristina , Nicolescu Alina , Zgardan Cristina , Simionescu Bogdan C. , Barboiu Mihail 
Published: March 2014

AbstractAn investigation of the constitutional adaptive gelation process of chitosan/cinnamaldehyde (C/Cy) dynagels is reported. These gels generate timely variant macroscopic organization across extended scales. In the first stage, imine‐bond formation takes place “in‐water” and generates low‐ordered hydrogels. The progressive formation of imine bonds further induces “out‐of‐water” increased reactivity within interdigitated hydrophobic self‐assembled layers of Cy, with a protecting environmental effect against hydrolysis and that leads to the stabilization of the imine bonds. The hydrophobic swelling due to Cy layers at the interfaces reaches a critical step when lamellar self‐organized hybrids are generated (24 hours). This induces an important restructuration of the hydrogels on the micrometric scale, thus resulting in the formation of highly ordered microporous xerogel morphologies of high potential interest for chemical separations, drug delivery, and sensors.
Trapping of Organophosphorus Chemical Nerve Agents in Water with Amino Acid Functionalized Baskets
Authors: Ruan Yian , Dalkiliç Erdin , Peterson Paul W. , Pandit Aroh , Dastan Arif , Brown Jason D. , Polen Shane M. , Hadad Christopher M. , Badjić Jovica D. 
Published: March 2014

AbstractWe prepared eleven amino‐acid functionalized baskets and used 1H NMR spectroscopy to quantify their affinity for entrapping dimethyl methylphosphonate (DMMP, 118 Å3) in aqueous phosphate buffer at pH=7.0±0.1; note that DMMP guest is akin in size to chemical nerve agent sarin (132 Å3). The binding interaction (Ka) was found to vary with the size of substituent groups at the basket′s rim. In particular, the degree of branching at the first carbon of each substituent had the greatest effect on the host‐guest interaction, as described with the Verloop′s B1 steric parameter. The branching at the remote carbons, however, did not perturb the encapsulation, which is important for guiding the design of more effective hosts and catalysts in future.
m‐Metallaphenol: Synthesis and Reactivity Studies
Authors: Han Feifei , Wang Tongdao , Li Jinhua , Zhang Hong , Xia Haiping 
Published: March 2014

AbstractTreatment of the osmium complex [Os{CHC‐(PPh3)CH(OH)‐η2‐C≡CH}(PPh3)2(NCS)2] (1) with excess triethylamine produces the first m‐metallaphenol complex [Os{CHC(PPh3)CHC(OH)CH}(PPh3)2(NCS)2] (2). The NMR spectroscopic and structural data as well as the nucleus‐independent chemical‐shift (NICS) values suggest that osmaphenol 2 has aromatic character. The reactivity studies demonstrate that 2 can react with different isocyanates to form the annulation reaction products [Os{CHC(PPh3)CHC(OCONR)C}(PPh3)2(NCS)2] (R=Ph (3), iPr (7), Bn (8)) via the carbamate intermediates [Os{CHC(PPh3)CHC(O‐CONHR)CH}(PPh3)2(NCS)2] (R=Ph (4), iPr (5), Bn (6)). In addition, the similar annulation reactions can be extended to other unsaturated compounds containing N–C multiple bonds, for example, isothiocyanates, pyridine, and sodium thiocyanate, which can produce the corresponding fused osmabenzene complexes. In contrast, the reactions of 2 with common electrophiles, such as NOBF4, NO2BF4, N‐bromosuccinimide, and N‐chlorosuccinimide only led to the decomposition of the metallaphenol ring. The experimental results suggest that 2 is very electrophilic and readily reacts with nucleophiles, which is mainly due to the metal center and the strong electron‐withdrawing phosphonium group.
RhIII‐Catalyzed Hydroacylation Reactions between N‐Sulfonyl 2‐Aminobenzaldehydes and Olefins
Authors: Zhang Tao , Qi Zisong , Zhang Xueyun , Wu Lamei , Li Xingwei 
Published: March 2014

AbstractMetal‐catalyzed hydroacylation of olefins represents an important atom‐economic synthetic process in CH activation. For the first time highly efficient RhIIICp*‐catalyzed hydroacylation was realized in the coupling of N‐sulfonyl 2‐aminobenzaldehydes with both conjugated and aliphatic olefins, leading to the synthesis of various aryl ketones. Occasionally, oxidative coupling occurred when a silver(I) oxidant was used.
Practical color barrier‐free illumination for deuteranopia using LEDs
Authors: Tamura Shigeharu , Okamoto Yosuke , Nakagawa Seiji , Sakamoto Takashi , Shigeri Yasushi 
Published: March 2014

AbstractHere, we propose a color barrier‐free illumination consisting of white, red, and blue LEDs for people with deuteranopia‐type defects in color perception. Color perceptions of 20 volunteers with normal vision and four examinees of deuteranopia were evaluated by both the Ishihara test for color blindness and the Farnsworth Panel D‐15 test under color barrier‐free illumination. The illumination was comparably effective, not only for discriminating between red and green but also for discrimination of the hues on a color chip continuously. © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 218–223, 2015
Pharmacokinetics of rabeprazole granules versus tablets, and the effect of food on the pharmacokinetics of rabeprazole granules in healthy adults—cross‐study comparison
Authors: Thyssen An , Solanki Bhavna , Gonzalez Martha , Leitz Gerhard , Treem William , Mannaert Erik 
Published: March 2014

AbstractThe primary objective was to compare the pharmacokinetics (PK) of rabeprazole granules versus rabeprazole tablets, and assess the effect of food on the PK of rabeprazole granules. Data from three phase 1, open‐label, single‐dose, randomized, crossover studies in healthy adult participants are presented separately and as a cross‐study comparison; study 1: PK of phase 1 rabeprazole granules versus rabeprazole tablets under fasting conditions; study 2: PK of phase 3 rabeprazole granules versus phase 1 rabeprazole granules; study 3: bioequivalence of to‐be‐marketed rabeprazole granules (sprinkle capsules) versus phase 3 rabeprazole granules; and assessment of the food effect for the to‐be‐marketed rabeprazole granules. Overall, 123 of 130 participants enrolled completed the studies. The overall plasma exposure as measured by area under the plasma concentration–time curve (AUC) was comparable between rabeprazole granules and tablets; mean peak plasma concentration (Cmax) was lower for the granules compared with tablets. The plasma elimination half‐life was short and independent of formulation. Food intake prior to administration of the to‐be‐marketed granules delayed the absorption and reduced the estimated parameters for bioavailability by 55% (Cmax) and 28% (AUCinf). Rabeprazole was well‐tolerated.
Low Effective Activation Energies for Oxygen Release from Metal Oxides: Evidence for Mass‐Transfer Limits at High Heating Rates
Authors: Jian Guoqiang , Zhou Lei , Piekiel Nicholas W. , Zachariah Michael R. 
Published: March 2014

AbstractOxygen release from metal oxides at high temperatures is relevant to many thermally activated chemical processes, including chemical‐looping combustion, solar thermochemical cycles and energetic thermite reactions. In this study, we evaluated the thermal decomposition of nanosized metal oxides under rapid heating (∼105 K s−1) with time‐resolved mass spectrometry. We found that the effective activation‐energy values that were obtained using the Flynn–Wall–Ozawa isoconversional method are much lower than the values found at low heating rates, indicating that oxygen transport might be rate‐determining at a high heating rate.
Sol–Gel Titanium Dioxide Blocking Layers for Dye‐Sensitized Solar Cells: Electrochemical Characterization
Authors: Kavan Ladislav , Zukalova Marketa , Vik Ondrej , Havlicek David 
Published: March 2014

AbstractCompact, thin TiO2 films are grown on F‐doped SnO2 (FTO) by dip‐coating from precursor solutions containing poly(hexafluorobutyl methacrylate) or hexafluorobutyl methacrylate as the structure‐directing agents. The films are quasi‐amorphous, but crystallize to TiO2 (anatase) upon heat treatment at 500 °C in air. Cyclic voltammetry experiments performed using Fe(CN)63−/4− or spiro‐OMeTAD as model redox probes selectively indicate the pinholes, if any, in the layer. The pinhole‐free films on FTO represent an excellent rectifying interface at which no anodic faradaic reactions occur in the depletion state. The flat‐band potentials of the as‐grown films are upshifted by 0.2–0.4 V against the values predicted for a perfect anatase single‐crystal surface, but they still follow the Nernstian pH dependence. The optimized buffer layer is characterized by a combination of quasi‐amorphous morphology (which is responsible for the blocking function) and calcination‐induced crystallinity (which leads to fast electron injection and electron transport in the conduction band). The latter manifests itself by a reversible charging of the chemical capacitance of TiO2 in its accumulation state. The capacitive‐charging capability and pinhole formation significantly depend on the post‐deposition heat treatment.