bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polylactides with “green” plasticizers: Influence of isomer composition
Authors: Arias Veluska , Höglund Anders , Odelius Karin , Albertsson Ann‐Christine 
Published: June 2013

ABSTRACTSynthesized polylactides (PLA) with different D‐isomer contents in the polymer chain were melt‐blended with a series of “green” plasticizers by extrusion. Mechanical and thermal properties as well as the morphology of the plasticized materials were characterized to demonstrate how the combination of PLA with different D‐contents and plasticizer controls the material properties. After addition of acetyl tributyl citrate (ATC), the elongation at break for PLA with a low D‐isomer content was twice as high as that for PLAs with high D‐isomer contents. Similar variations in the plasticization effect on the PLAs were also observed with the other plasticizers used, glyceryl triacetate (GTA), glycerol trihexanoate (GTH) and polyethylene glycol (PEG). In order to continue with the development of renewable polymers in packaging applications, the interrelation between a plasticizer and a specific polymer needs to be understood. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2962–2970, 2013
Innovative films with tunable permeability for fresh vegetable packaging applications
Authors: Scafati Santolo Taglialatela , Boragno Luca , Losio Simona , Conzatti Lucia , Lanati Simonetta , Sacchi Maria Carmela , Stagnaro Paola 
Published: June 2013

ABSTRACTBlends of a commercial polypropylene (PP), typically used as food contact material, with increasing amounts of poly(4‐methyl‐1‐pentene) (PMP) are prepared in a twin‐screw extruder to obtain thin films with improved gas permeation for fresh vegetable packaging. Permeability, haze, and transparency of monolayer films produced by casting are investigated under conditions mimicking the industrial ones. O2 and CO2 permeability can be tuned by increasing PMP content in the blends from 5 to 20 wt %. Transparency and haze are practically unchanged in the presence of low content of PMP. Moreover, tensile and rheological tests show that PMP does not significantly affect the related properties of blends compared to the neat PP matrix, thus allowing for the industrial applicability of these new formulations. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 39503.
Effective thermal conductivity of 3,5‐diaminobenzoyl‐functionalized multiwalled carbon nanotubes/epoxy composites
Authors: Pongsa Uraiwan , Somwangthanaroj Anongnat 
Published: June 2013

ABSTRACTTo obtain homogeneous dispersion and good interfacial interaction between MWCNT and polymer matrix, the functionalization of MWCNTs with 3,5‐diaminobenzoic acid (DAB) via a direct Friedel‐Crafts acylation was accomplished. FTIR, XPS, and FT‐Raman analysis was performed to confirm that diaminobenzoyl moieties were successfully grafted onto MWCNT surface with less structural damage. The incorporation of diaminobenzoyl‐functionalized MWCNTs (DAB‐MWCNTs) into epoxy matrix can substantially enhance storage modulus (E′) as well as glass transition temperature (Tg) and reduce the coefficient of thermal expansion. The thermal conductivity enhancement can be observed with DAB‐MWCNTs probably due to good dispersion and decreased interfacial thermal resistance between MWCNT and polymer matrix. The Maxwell‐Eucken, Lewis‐Nielsen, and MG‐EMA models were used to evaluate theoretical thermal conductivity. Moreover, epoxy resin incorporated with hybrid fillers, which consisted of DAB‐MWCNTs and silicon nitride exhibit higher thermal conductivity than those with single filler, thereby forming perfectly heat conductive pathways. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3184–3196, 2013
Effect of formulation and processing conditions on light shielding efficiency of thermotropic systems with fixed domains based on UV curing acrylate resins
Authors: Weber Andreas , Schlögl Sandra , Resch Katharina 
Published: June 2013

ABSTRACTWithin this study relationships between material formulation and processing parameters and the morphology (vacuole formation) of thermotropic systems with fixed domains (TSFD) for overheating protection purposes were investigated. Main aim was on improving light shielding efficiency of TSFD based on UV curable acrylate resins by optimization of selected key parameters including photo‐initiator type and content, type of reactive diluent, radiation intensity/dose, and thermal treatment of layers during manufacturing. Variations of type of reactive diluent and thermal treatment had a minor effect on overheating protection performance. Utilization of photo‐bleaching photo‐initiator of acylphospine oxide type instead of a blend of conventional Type I (α‐hydroxy ketone type) and Type II (benzophenone) photo‐initiators enabled reduction of radiation dose to achieve properly cured layers. The results revealed that a significant reduction of radiation intensity/dose prevented formation of vacuoles. Consequently, light shielding efficiency of TSFD was enhanced significantly. Nevertheless, obtained scattering domain size was inappropriate for optimum light shielding efficiency and requires further optimization strategies. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3299–3310, 2013
Lignin liquefaction under microwave heating
Authors: Sequeiros Ane , Serrano Luis , Briones Rodrigo , Labidi Jalel 
Published: June 2013

ABSTRACTOrganosolv lignin from olive tree pruning was subjected to liquefaction under microwave heating and modifying the experimental conditions (time, temperature, and concentration of catalyst) according to an experimental design. The organosolv lignin and obtained polyols were characterized using attenuated‐total reflection infrared spectroscopy (ATR‐IR), thermogravimetric analysis (TGA), gel permeation chromatography, and another parameter such as the hydroxyl number (IOH). The ATR‐IR and the TGA results showed that the solvents (polyethylene glycol #400 and glycerol) reacted with the lignin being present in the final product. The optimal polyol showed a liquefaction yield of 99.07% that was obtained in 5 min of reaction at 155°C with 1% of sulphuric acid. The liquefaction product showed a hydroxyl number of 811.8 mg KOH/g, suitable to be used as a precursor in polyurethane foam synthesis. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3292–3298, 2013
High resolution modelling of valley cold pools
Authors: Vosper Simon , Carter Emilie , Lean Humphrey , Lock Adrian , Clark Peter , Webster Stuart 
Published: June 2013

AbstractThe Met Office Unified Model has been adapted to run with a 100 m horizontal grid length for a region of complex terrain whose valleys are too narrow to be represented in the operational forecast (1.5 km grid length) model. Forecasts of temperatures are compared with observations from the COLd air Pooling EXperiment. The model provides a realistic representation of valley cold pools which form during stable nights, although the predictions are shown to be sensitive to vertical resolution. Reducing the vertical grid spacing near the surface results in lower night‐time temperatures and larger, more realistic, valley–hill temperature contrasts.
Interaction of Lactobacillus vini with the ethanol‐producing yeasts Dekkera bruxellensis and Saccharomyces cerevisiae
Authors: Tiukova Ievgeniia , Eberhard Thomas , Passoth Volkmar 
Published: June 2013

AbstractLactobacillus vini was recently described as a contaminant in industrial ethanol fermentations and its co‐occurrence with Dekkera bruxellensis was noted. We investigated the growth characteristics of L. vini in cocultivation together with either Saccharomyces cerevisiae or D. bruxellensis. Lower cell numbers of both the yeasts and L. vini as well as a decrease in ethanol and lactate formation in mixed batch cultures compared with pure cultures were noted. L. vini formed cell aggregates (flocs) in all cultivation media with different shapes in Man–Rogosa–Sharpe and yeast extract–peptone–dextrose media. Flocs’ size and proportion of cells bound to flocs increased with increasing ethanol concentration. In coculture, formation of lactic acid bacteria–yeast cell aggregates consisting of a bacterial core with an outer layer of yeast cells was observed. L. vini–D. bruxellensis flocs had a bigger surface, due to cells protruding from the pseudomycelium. The involvement of mannose residues in the flocculation between L. vini and yeasts was tested. The presence of mannose induced deflocculation in a concentration‐dependent manner. Less mannose was required for the deflocculation of D. bruxellensis as compared with S. cerevisiae.
Absent/weak CD44 intensity and positive human papillomavirus (HPV) status in oropharyngeal squamous cell carcinoma indicates a very high survival
Authors: Näsman Anders , Nordfors Cecilia , Grün Nathalie , Munck‐Wikland Eva , Ramqvist Torbjörn , Marklund Linda , Lindquist David , Dalianis Tina 
Published: June 2013

AbstractPatients with human papillomavirus DNA positive (HPVDNA+) oropharyngeal squamous cell carcinoma (OSCC) have better clinical outcome than those with HPV DNA negative (HPVDNA−) OSCC upon intensive oncological treatment. All HPVDNA+ OSCC patients may not require intensive treatment, however, but before potentially deintensifying treatment, additional predictive markers are needed. Here, we examined HPV, p16INK4a, and CD44 in OSCC in correlation to clinical outcome. Pretreatment tumors from 290 OSCC patients, the majority not receiving chemotherapy, were analyzed for HPV DNA by Luminex and for p16INK4a and CD44 by immunohistochemistry. 225/290 (78%) tumors were HPVDNA+ and 211/290 (73%) overexpressed p16INK4a, which correlated to presence of HPV (P < 0.0001). Presence of HPV DNA, absent/weak CD44 intensity staining correlated to favorable 3‐year disease‐free survival (DFS) and overall survival (OS) by univariate and multivariate analysis, and likewise for p16INK4a by univariate analysis. Upon stratification for HPV, HPVDNA+ OSCC with absent/weak CD44 intensity presented the significantly best 3‐year DFS and OS, with >95% 3‐year DFS and OS. Furthermore, in HPVDNA+ OSCC, p16INK4a+ overexpression correlated to a favorable 3‐year OS. In conclusion, patients with HPVDNA+ and absent/weak CD44 intensity OSCC presented the best survival and this marker combination could possibly be used for selecting patients for tailored deintensified treatment in prospective clinical trials.
Heteropoly Acid Catalysts for the Synthesis of Fragrance Compounds from Biorenewables: Cycloaddition of Crotonaldehyde to Limonene, α‐Pinene, and β‐Pinene
Authors: Costa Vinícius V. , da Silva Rocha Kelly A. , Mesquita Rafaela A. , Kozhevnikova Elena F. , Kozhevnikov Ivan V. , Gusevskaya Elena V. 
Published: June 2013

AbstractThe interaction of widespread monoterpenes limonene, α‐pinene, and β‐pinene with crotonaldehyde using silica‐supported tungstophosphoric heteropoly acid H3PW12O40 and its acidic cesium salt Cs2.5H0.5PW12O40 as solid acid catalysts in dichloroethane solutions results in cycloaddition, which gives the same fragrant oxabicyclo[3.3.1]nonene product in a high yield. The product is likely to be formed through an α‐terpenyl carbenium ion intermediate, which is generated from monoterpene protonation and undergoes nucleophilic attack by crotonaldehyde. Both H3PW12O40 and Cs0.5H0.5PW12O40 are efficient and truly heterogeneous cycloaddition catalysts.
The Effect of Noncatalytic Cations on the Activity and Selectivity of Nickel‐Exchanged X Zeolites for Propene Oligomerization
Authors: Mlinar Anton N. , Ho Otto C. , Bong Gerry G. , Bell Alexis T. 
Published: June 2013

AbstractA series of alkali metal or alkaline earth‐exchanged NiX (X=faujasite zeolite, Si/Al=1.2) zeolites containing approximately 0.6 wt % Ni as Ni2+ cations were examined as catalysts for propene oligomerization at 453 K and 5 bar (500 kPa). In the presence of propene, the activity of alkali metal‐exchanged zeolites (NiLiX, NiNaX, and NiKX) increased with time on stream, reached a maximum, then decreased, and finally reached steady state. In contrast, the activity of alkaline earth‐exchanged zeolites (NiMgX, NiCaX, and NiSrX) was high initially and then decreased until steady‐state activity was achieved. The primary product formed in all cases was hexene (90 %), and nonene was the only other product observed (10 %). Both the rate of propene dimerization and the ratio of branched to linear hexene isomers were determined to depend on the identity of the charge‐compensating cation, with the dimerization rate and degree of dimer branching increasing with increasing free volume in the zeolite supercages. The apparent activation energy for trimer formation was greater than that for dimer formation, which suggests that steric constraints imposed by the zeolite may inhibit the growth of larger oligomers.
Plasmon‐Enhanced Photocatalysis on Anisotropic Gold Nanorod Arrays
Authors: Kubus Levent , Erdogan Hakan , Cetin S. Sebnem , Biskin Erhan , Demirel Gokhan 
Published: June 2013

AbstractThe field of photocatalysis is an active area owing to the possible contributions to solve some challenging problems such as sustainable energy production, environmental pollution control, and even global warming. Unfortunately, traditional photocatalysts, especially semiconductors, suffer from inherent deficiencies, which include high activation barriers, the low mobility of charge carriers, and poor long‐term stabilities. Herein, we demonstrate a plasmonic photocatalyst based on unidirectional gold nanorod arrays fabricated by using the oblique‐angle deposition (OAD) technique. The fabricated gold nanorod arrays exhibit a remarkable plasmonic anisotropy, which depends on the direction of the incoming light. By employing these arrays as a plasmonic catalyst, a clear improvement and control in the catalytic reduction of o‐nitroaniline to 1,2‐benzenediamine, depending on the directionalities and anisotropic plasmonic properties of the gold nanorods, was obtained. These results suggest that such unique characteristics of directional gold nanorod arrays could greatly impact several technological areas, not only in plasmon‐enhanced photocatalysis but in biosensing and optofluidic applications.
Beckmann Rearrangement of Cyclohexanone Oxime in a Microreactor Setup with Internal Recirculation
Authors: Zuidhof N. T. , de Croon M. H. J. M. , Schouten J. C. , Tinge J. T. 
Published: June 2013

AbstractBeckmann rearrangement of cyclohexanone oxime dissolved in cyclooctane with oleum to ϵ‐caprolactam was demonstrated in a microreactor setup with internal recirculation operated in continuous mode. The core of the setup comprised a 316 stainless‐steel micromixer consisting of 17 split‐and‐recombine units connected to a delay loop, a 316 stainless‐steel microchannel reactor with an internal diameter of 0.250 mm and a length of 0.50 m. At 100 °C, the conversion of cyclohexanone oxime was complete and the selectivity towards ϵ‐caprolactam was approximately 99 %. The solvent cyclooctane reduces the observed purity of the produced oleum/ϵ‐caprolactam. This reduction in purity might be a severe hurdle for usage of a solvent on the industrial scale in the Beckmann rearrangement of cyclohexanone oxime in oleum to ϵ‐caprolactam.
Molecular Thermal Hysteresis in Helix‐Dimer Formation of Sulfonamidohelicene Oligomers in Solution
Authors: Shigeno Masanori , Kushida Yo , Yamaguchi Masahiko 
Published: June 2013

AbstractSulfonamidohelicene oligomers up to the nonamer level were synthesized by the repeated coupling reactions of a building block. A tetramer formed a helix dimer in 1,3‐difluorobenzene, which unfolded to a random coil with heating. This structural change exhibited thermal hysteresis in which different thermal responses were observed in the course of temperature increase and decrease. The feature of the hysteresis was examined under different heating/cooling modes, and the mechanisms are discussed on the basis of the population change and the presence of an induction period. A proposal regarding the use of thermal hysteresis for sensing a temperature increase/decrease is also given.
Small D–π–A Systems with o‐Phenylene‐Bridged Accepting Units as Active Materials for Organic Photovoltaics
Authors: Leliège Antoine , Grolleau Jérémie , Allain Magali , Blanchard Philippe , Demeter Dora , Rousseau Théodulf , Roncali Jean 
Published: June 2013

AbstractDonor–acceptor (D–π–A) systems that combine triarylamine donor blocks and dicyanovinyl (DCV) acceptor groups have been synthesized. Starting from the triphenylamine (TPA)thiopheneDCV compound (1) as a reference system, various synthetic approaches have been developed for controlling the light‐harvesting properties and energy levels of the frontier orbitals in this molecule. Thus, the introduction of methoxy groups onto TPA, the replacement of one phenyl ring of TPA by a thiophene ring, or the extension of the π‐conjugating spacer group lead to the modulation of the HOMO level. On the other hand, the fusion of the DCV group onto the vicinal thiophene ring by an ortho‐phenylene bridge allows for a specific fine‐tuning of the LUMO level. The electronic properties of the molecules were analyzed by using UV/Vis spectroscopy and cyclic voltammetry and the compounds were evaluated as donor materials in basic bilayer planar heterojunction solar cells by using C60 as acceptor material. The relationships between the electronic properties of the donors and the performance of the corresponding photovoltaic devices are discussed. Bilayer planar heterojunction solar cells that used reference compound 1 and C70 afforded power‐conversion efficiencies of up to 3.7 %.
Synthesis and Transformations of Novel L‐Phenylalanine Derived Pyrazolidin‐3‐ones
Authors: Grošelj Uroš , Golobič Amalija , Svete Jurij , Stanovnik Branko 
Published: June 2013

ABSTRACTA simple and straightforward four‐step synthesis of novel diastereomeric L‐phenylalanine‐derived pyrazolidin‐3‐ones is described. The absolute configuration of the novel C(5) stereogenic centre has been unambiguously determined by single crystal X‐ray analysis and via chemical interconversions. A series of novel thiourea derived pyrazolidinones have been prepared and tested as potential organocatalysts. N(1) un‐substituted pyrazolidinones can be used for the construction of a novel type of bicyclic heterocycles and other selective derivatizations. Chirality 25:541–555, 2013. © 2013 Wiley Periodicals, Inc.
Effect of the Liquid Viscosity on the Rheological Behavior of Foams
Authors: Lexis Meike , Willenbacher Norbert 
Published: June 2013

AbstractDie rheologischen Eigenschaften von Schäumen sind für die Qualität vieler Produkte von entscheidender Bedeutung. Um die charakteristischen Parameter scheinbare Fließgrenze und Speichermodul bei Kenntnis der physikalischen Eigenschaften Blasengröße, Oberflächenspannung und Gasvolumenanteil voraussagen zu können, existieren bereits Modellgleichungen. In dieser Arbeit wird gezeigt, dass diese nicht alle Einflussgrößen berücksichtigen. Präsentiert wird eine empirische Modellgleichung, die den Einfluss der Viskosität der kontinuierlichen Phase berücksichtigt und die Verteilung der Blasengrößen auf physikalisch sinnvolle Weise einbezieht. Darüber hinaus wird verdeutlicht, dass Grenzflächeneigenschaften eine entscheidende Rolle für die Schaumrheologie spielen.
Membrane Supported Virus Separation from Biological Solutions
Authors: Grein Tanja A. , Kovacs Zoltan , Ebrahimi Mehrdad , Michalsky Ronald , Czermak Peter 
Published: June 2013

AbstractIndustrial production of cell culture‐derived viruses or virus‐like particles for gene therapy or as expression systems for vaccine production is a complex multi‐step process. Unfortunately, process intensification and optimization efforts mostly focus on increased reactor yields, neglecting the potential for materials design and process development for downstream unit operations that often are the bottleneck of a biopharmaceutical manufacturing process. Membrane‐based virus filtration represents an economical trade‐off towards biotechnological downstream processing with moderate to high yields and purity on one hand and relative fast process kinetics, and thereby reduced equipment size and costs, on the other hand. This article provides a short review of recent development and applications of membrane materials and membrane‐based unit operations for virus separation in the manufacturing trains of vaccines or viral vectors for gene therapy.
Experimental heat transfer and friction factor studies through a square duct fitted with helical screw tapes
Authors: Patil Suhas , Vijay Babu P. 
Published: June 2013

AbstractExperimental investigations of friction factor and heat transfer characteristics through a square duct fitted with helical screw tapes of various twist ratios have been studied under nearly uniform wall temperature conditions. The experimental results reveal that the use of helical screw tapes leads to a considerable increase in heat transfer and friction loss over those of a plain square duct. The Nusselt number increases with the rise of Reynolds number and the reduction of twist ratio. The Performance evaluation criteria have been presented and maximum performance ratio was observed for minimum twist ratio.
From On‐Target to Off‐Target Activity: Identification and Optimisation of Trypanosoma brucei GSK3 Inhibitors and Their Characterisation as Anti‐Trypanosoma brucei Drug Discovery Lead Molecules
Authors: Woodland Andrew , Grimaldi Raffaella , Luksch Torsten , Cleghorn Laura A. T. , Ojo Kayode K. , Van Voorhis Wesley C. , Brenk Ruth , Frearson Julie A. , Gilbert Ian H. , Wyatt Paul G. 
Published: June 2013

AbstractHuman African trypanosomiasis (HAT) is a life‐threatening disease with approximately 30 000–40 000 new cases each year. Trypanosoma brucei protein kinase GSK3 short (TbGSK3) is required for parasite growth and survival. Herein we report a screen of a focused kinase library against T. brucei GSK3. From this we identified a series of several highly ligand‐efficient TbGSK3 inhibitors. Following the hit validation process, we optimised a series of diaminothiazoles, identifying low‐nanomolar inhibitors of TbGSK3 that are potent in vitro inhibitors of T. brucei proliferation. We show that the TbGSK3 pharmacophore overlaps with that of one or more additional molecular targets.
Solid‐State NMR Correlation Experiments and Distance Measurements in Paramagnetic Metalorganics Exemplified by Cu‐Cyclam
Authors: Kumara Swamy Shashi K. , Karczmarska Agnieszka , Makowska‐Janusik Malgorzata , Kassiba Abdelhadi , Dittmer Jens 
Published: June 2013

AbstractWe show how to record and analyze solid‐state NMR spectra of organic paramagnetic complexes with moderate hyperfine interactions using the Cu‐cyclam complex as an example. Assignment of the 13C signals was performed with the help of density functional theory (DFT) calculations. An initial assignment of the 1H signals was done by means of 1H–13C correlation spectra. The possibility of recording a dipolar HSQC spectrum with the advantage of direct 1H acquisition is discussed. Owing to the paramagnetic shifting the resolution of such paramagnetic 1H spectra is generally better than for diamagnetic solid samples, and we exploit this advantage by recording 1H–1H correlation spectra with a simple and short pulse sequence. This experiment, along with a Karplus relation, allowed for the completion of the 1H signal assignment. On the basis of these data, we measured the distances of the carbon atoms to the copper center in Cu‐cyclam by means of 13C R2 relaxation experiments combined with the electronic relaxation determined by EPR.