bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improvement in physical and electrical properties of poly(vinyl alcohol) hydrogel conductive polymer composites
Authors: Phuchaduek Winatthakan , Jamnongkan Tongsai , Rattanasak Ubolluk , Boonsang Siridech , Kaewpirom Supranee 
Published: April 2015

ABSTRACTWith an aim to develop anti‐electrostatic discharge materials based on biodegradable polymers, poly(vinyl alcohol) films composited with two different conductive fillers (carbon black and aluminium) at various fillers contents (20−60%wt), were manufactured using solvent‐casting technique. The mechanical properties of such the films were investigated through tensile stress‐strain tests. Wettability and morphology of the composite films were performed by water contact angle measurement and SEM, respectively. Young's modulus of the composite films can be increased with the addition of conductive fillers. The surface of the composite films showed non‐homogeneous appearance, in which the phase boundary within the composites was clearly observed and the conductive fillers formed aggregation structure at high filler concentration. In addition, the composite films exhibited better hydrophobicity when higher conductive filler content was added. TGA results suggested that both carbon black and aluminum have proven their efficiency to enhance thermal stability of poly(vinyl alcohol). Investigation of cross‐cut adhesion performance of the prepared composite films revealed that carbon black‐filled composites exhibited excellent adhesion strength. The effect of conductive filler content on surface resistivity of the composite films was also examined. The experimental results confirmed that both the fillers used in this study can improve the electrical conductivity of poly(vinyl alcohol) hydrogel. The surface resistivity of the composite films was reduced by several orders of magnitude when the filler of its critical concentration was applied. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42234.
Fast space charge behavior in heat‐treated polypropylene films
Authors: Zheng Feihu , Gu Min , Dong Jianxing , An Zhenlian , Lei Qingquan , Zhang Yewen 
Published: April 2015

ABSTRACTIn this study, the characterization of the short‐circuit current within hundreds of nanoseconds is proposed to study the effect of heat treatment on fast space charge behavior in the polarized biaxially oriented polypropylene (BOPP) films. The BOPP films were cooled either quickly or slowly during the sample preparation. The damped oscillating feature was found in the short‐circuit current of all the polarized film samples, but the periods of the oscillating current for the samples prepared by fast cooling rate decrease faster. Bipolar space charge injection in the polarized BOPP films was observed by the thermal pulse (TP) measurement. The variation feature of the short‐circuit current was considered to be associated with the varying fast space charge behavior, which depended on the varying structural traps modified by the heat treatment during the sample preparation. The sample subjected to fast cooling process was with relatively shallow trap level revealed by the thermally stimulated current method, which led to higher mobility of the escaping charge in the sample. The TP measurements were utilized to analyze space charge features in the polarized BOPP films. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42235.
Crystal Engineering with the New Linker Tolanedisulfonic Acid (H2TDS): Helical Chains in Zn(TDS)(DMA)3, Linear Chains in Zn(TDS)(NMP)3, and Complex Anions in [HDMA]2[Zn(TDS)2(DMA)3](DMA)2
Authors: Zitzer Christina , Muesmann Thomas W. T. , Christoffers Jens , Wickleder Mathias S. 
Published: April 2015

AbstractReaction of 4,4′‐tolanedisulfonic acid, H2TDS, with zinc hydroxide in dimethylacetamide, DMA, under solvothermal conditions led to the coordination polymer Zn(TDS)(DMA)3 (I). In the crystal structure [trigonal, P3221, Z=3, a=1175.0(1) pm, c=1949.5(1) pm, R1; wR2 (Io> 2σ(Io))=0.0393; 0.0921] the disulfonate anions linked the Zn2+ ions into helical chains according to ∞1[Zn(DMA)3/1(TDS)2/2] (I) causing the chirality of the compound. By using higher concentrations of H2TDS in the starting mixture the compound [HDMA]2[Zn(TDS)2(DMA)3](DMA)2 (II) was formed. The structure [monoclinic, Cc, Z=4, a=1201.5(1) pm, b=1996.0(1) pm, c=2749.2(2) pm, β=101.897(2)°, R1; wR2 (Io> 2σ(Io))=0.0699; 0.2017] displayed the complex anion [Zn(TDS)2(DMA)3]2− which was a perfect cut‐off of the helical chain in I. Charge compensation was achieved by protonated DMA molecules. If N‐methylpyrrolidone, NMP, was chosen as a solvent, the sulfonate Zn(TDS)(NMP)3 (III) [monoclinic, I2/a, Z=4, a=1575.7(1) pm, b=1077.3(1) pm, c=1870.0(1) pm, β=101.189(9)°, R1; wR2 (Io> 2σ(Io))=0.0563; 0.1320] was obtained. Similarly to the findings for I, the formation of chains according to ∞1[Zn(NMP)3/1(TDS)2/2] was observed. However, due to the more bulky NMP molecules these chains were no longer helical but straight instead.
Bemessungsdiagramme für den biegebeanspruchten Stab im Holzbau
Authors: Moosbrugger Thomas , Bogensperger Thomas , Krenn Harald 
Published: April 2015

AbstractIn der vorliegenden Arbeit werden, aufbauend auf die Bemessungsdiagramme für einen Biegeträger einer Dachkonstruktion mit homogenem Stabquerschnitt [1], die Erweiterung um den inhomogenen Stabquerschnitt (geschichteter Verbundquerschnitt) sowie die Implementierung der Schwingungsnachweise gezeigt. Während bei den Bemessungsdiagrammen für den homogenen Stabquerschnitt sowohl die ULS‐ als auch die SLS‐Nachweise von Relevanz waren, treten bei Erweiterung um die Schwingungsnachweise sowie aufgrund der Einflüsse des inhomogenen Querschnittsaufbaues vorrangig die SLS‐Nachweise auf. Das Schwingungsverhalten von Deckentragwerken wird wesentlich durch die Lagerungsbedingungen beeinflusst. Die Einspanneffekte im Bereich des Anschlussdetails Wand‐Decke zufolge der Geschossauflasten werden bei der Bestimmung der Eigenfrequenz berücksichtigt.Design charts for a single spanned timber beam under bending – Part 2: Floor structures with inhomogeneous beam cross‐sectionThis paper presents an application of design charts for inhomogeneous cross‐sections (layered composite section) and the implementation of vibration design criteria as extension of the charts for beams with homogeneous cross‐sections in roof‐structures according to selected European Design Standards published in [1]. While ULS and SLS criteria were nearly equally governing for the homogeneous cross‐section, mainly SLS criteria are now governing due to the extension with vibrations and the influences of the inhomogeneous cross‐sections. The vibrational behavior of floors is essentially influenced by the support conditions. Effects of moment restraints at the wall‐floor‐wall detail, activated by wall‐loads from stories above, are systematically being taken into account.
Dynamische Stabwerkmodelle
Authors: Brückner Frank , Weischede Dietger 
Published: April 2015

AbstractDie Idee, Bewegungsprozesse anhand von Stabwerkmodellen zu analysieren (= dynamische Stabwerkmodelle), basiert auf der Kraftflussanalyse mittels Stabwerkmodellen in der Statik [1, 2] und erweitert die Anwendung auf komplette dynamische Prozesse.Bei Stabwerkmodellen handelt es sich um eine vektorielle Analyse, die an jedem Knoten eines Systems grafisch durchgeführt wird. Bilden die Vektoren ein geschlossenes Krafteck, ist der betrachtete Knoten im Gleichgewicht und es handelt sich um einen statischen Zustand. Bleibt das Krafteck jedoch offen, treibt die resultierende Kraft den Knoten an, d. h., sie beschleunigt ihn in Abhängigkeit zu seiner Masse.Im Bauwesen spielen dynamische Prozesse nicht nur bei menscheninduzierten Schwingungen oder Bauwerksschwingungen durch Erdbeben oder Wind eine Rolle. Auch bei dem Tragfähigkeitsverlust einzelner Bauteile eines statisch bestimmten oder überbestimmten Tragwerks oder Tragwerkteils lagern sich die inneren Kräfte um, wodurch das gesamte System oder Teilsysteme kinematisch werden können. Die nachfolgende Bewegung des Systems hält so lange an, bis das Tragwerk mit einer neuen Geometrie ein Gleichgewicht findet und damit wieder statisch bestimmt wird.Dynamic strut‐and‐tie models – a graphical method to analyse dynamic processes using the exemple of an arc with a tension cableThe idea to analyse processes of movement by means of dynamic strut‐and‐tie models is based on the vectorial force flow analysis of static problems but expands its application to complete dynamic processes. A strut‐and‐tie model is a vectorial analysis of layouts and polygons of forces carried out graphically for each knot of a system. If the layout of the polygon of forces is closed, the knot analysed is in static equilibrium. If the polygon of forces is not closed, the knot will be accelerated by the resulting force depending on its mass.Analysing dynamic processes in building design does not only play an important role in case of human‐made vibrations or structural vibrations caused by earthquakes or wind. In addition to the usual problems a dynamic analysis may be carried out if the whole construction or individual components of the structure lose stability. If that happens, the internal forces of the structure come into a flow and the whole system or parts of it can possibly become kinematic. The following movement keeps going until the structure comes into a new static equilibrium with a new geometry.
Näherungsverfahren bei zweiachsiger Biegung mit Normalkraft
Authors: Duţulescu Eugen 
Published: April 2015

AbstractDie Nachweise der auf schiefe Biegung mit Normalkraft beanspruchten Stahlbetonquerschnitte werden iterativ, durch sukzessive Veränderungen der Stahlfläche, durchgeführt. Ein zweckmäßiges Rechenverfahren für die Bemessung bzw. Ermittlung der Tragfähigkeit wird vorgestellt.An Approach Method for biaxial Bending with axial Force.The design of the reinforced concret members subjected to skew bending with axial force is effected iteratively, trough succesive corrections of reinforcement area. An appropriate procedure for the determination of reinforcement respectively the verification of the load capacity is presented.
Querkrafttragfähigkeit von Stahlbetonbauteilen ohne Querkraftbewehrung
Authors: Tran Ngoc Linh , Kohoutek Jaroslav , Graubner Carl‐Alexander 
Published: April 2015

AbstractIn diesem Artikel wird ein neues Berechnungsmodell zur Abschätzung der Querkrafttragfähigkeit von Stahlbetonbauteilen ohne Querkraftbewehrung vorgestellt. Das innovative Querkraftmodell basiert auf analytischen Ansätzen und ermöglicht eine Vorhersage der Querkrafttragfähigkeit von Stahlbetonbauteilen mit großer Genauigkeit. Bei der Herleitung des Modells werden die wichtigsten Einflussgrößen auf die Querkrafttragfähigkeit dargestellt und auf ihren Anteil an der Gesamttragfähigkeit hin untersucht.Shear strength of reinforced concrete members without stirrupsIn this article a new calculation model for shear strength of reinforced concrete members without stirrups is introduced. The innovative shear model is based on analytic approaches and allows accurate prediction of the shear capacity of reinforced concrete members. In the derivation of the model the most important influencing parameters on the shear carrying capacity are presented and their shares on the total shear strength are examined.
Das Miteinander im Tumor
Authors: Gottfried Eva 
Published: April 2015

AbstractEin Tumor wurde früher als eine Masse mutierter Zellen betrachtet, die durch übermäßige Zellproliferation und verhinderten Zelltod entsteht. Inzwischen ist allgemein anerkannt, dass nicht nur Tumorzellen alleine, sondern auch ihre Nachbarzellen eine wesentliche Rolle bei der Entwicklung und Progression eines Tumors spielen. So scheint häufig eine effektive Anti‐Tumor‐Reaktion des Immunsystems auszubleiben, obwohl infiltrierende Immunzellen im Tumor zu finden sind. Als eine Ursache wird die Beeinflussung und Unterdrückung der Immunzellen durch das Tumormilieu diskutiert. Tumorzellen nutzen alternative Stoffwechselwege und sezernieren Metabolite, die Stromazellen wie Immunzellen modulieren. Hieraus ergeben sich vielversprechende Therapieansätze zur Hemmung der Tumorzellen mitsamt Reaktivierung einer effektiven Anti‐Tumor‐Immunantwort.
Biodiversitätsforschung – wohin geht die Reise?
Authors: Beck Erwin 
Published: April 2015

AbstractBewahrheitet sich der durch den globalen Wandel ausgelöste Verlust an biologischer Vielfalt, so sind die “Kräfte der Natur” bereits heute ernsthaft bedroht, denn die Leistungen der Natur sind Produkte von Organismenkonsortien, nicht Leistungen einzelner Arten. Allerdings kennt die Wissenschaft im günstigsten Falle erst etwa 10% der heute den Erdkreis bewohnenden Organismenarten, so dass auch der durch den globalen Wandel verursachte Verlust nicht belastbar bezifferbar und seine Effekte schwer darstellbar sind. Mit neuen Methoden versucht die Wissenschaft, die Wissenslücken zu schließen. Inzwischen hat sich die Politik des Komplexes Biologische Vielfalt “angenommen”, was im Hinblick auf den Schutzgedanken erfreulich ist, jedoch die Forschung durch bürokratische Hürden hemmt. Die aus der Biodiversitätskonvention (CBD) im Laufe der zurückliegenden 13 Jahre entstandenen Verhandlungen und Gesetzeswerke können, ähnlich wie beim Kyoto‐Protokoll, ihre finanzielle Motivation nicht verleugnen.
Gefiedertes Star‐Ensemble: Flugakrobaten und schillernde Sangeskünstler
Authors: Petrischak Hannes 
Published: April 2015

AbstractVielfältige Vogelgesänge verkünden den Frühling im Garten. Aus nächster Nähe lassen sich nun Revierstreitigkeiten, Balz, das Sammeln von Nistmaterial und von Futter für den Nachwuchs beobachten. Die Vogelwelt rund ums Haus wandelt sich im Laufe der Zeit: Während es einige früher eher scheue Bewohner von Wald und Feld zunehmend in Dörfer und Städte zieht, gibt es auch negative Tendenzen – vor allem bei Schwalben und Mauerseglern.
UHPLC‐MS method for determination of gambogic acid and application to bioavailability, pharmacokinetics, excretion and tissue distribution in rats
Authors: Zheng Zhifen , Ou Wanglu , Zhang Xinshi , Li Yongzhi , Li Yujuan 
Published: April 2015

AbstractA sensitive ultrahigh performance liquid chromatography tandem mass spectrometry (UHPLC‐MS) method was developed for determination of gambogic acid (GA) in rat plasma, urine, bile and main tissues. GA was separated on an Agilent Zorbax XDB–C18 column (50 × 2.1 mm, 1.8 µm) with gradient mobile phase at the flow rate of 0.2 mL/min. The detection was performed by negative electrospray ionization with multiple reaction monitoring mode. The calibration curves of GA were linear between 1.0 and 1000 ng/mL in rat plasma and bile and between 1.0 and 500 ng/mL in urine and tissues. The lowest limit of quantification for all matrices was 1.0 ng/mL. Both accuracy and precision of the assay were satisfactory. This validated method was firstly applied to bioavailability (BA), pharmacokinetics, excretion and tissue distribution in rats. The BAs of GA (40 and 80 mg/kg) in rats were 0.25 and 0.32%, respectively. GA was distributed extensively in rats after oral administration and exhibited the highest level in liver. GA reached the cumulative excretion amount of 25.3 ± 1.7 µg in bile and 0.275 ± 0.08 µg in urine after i.g. 80 mg/kg to rats at 24 h. The present results would be helpful for further clinical use of GA as a potential anticancer drug. Copyright © 2015 John Wiley & Sons, Ltd.
Transcatheter stenting of the systemic‐to‐pulmonary artery shunt: A 7‐year experience from a single tertiary center
Authors: Vaughn Gabrielle R. , Moore John W. , Mallula Kiran K. , Lamberti John J. , El‐Said Howaida G. 
Published: April 2015

BackgroundSystemic‐to‐pulmonary artery shunt (SPS) dysfunction can be deleterious in shunt dependent patients and traditionally have undergone surgical revision. Data on transcatheter stenting of SPS is limited. We sought to evaluate feasibility, safety and outcomes of stenting SPS.MethodsRetrospective review of all patients who underwent transcatheter SPS stenting from 1/2006 to 12/2013.ResultsOf 229 surgically implanted SPS, 25 transcatheter stent interventions were performed in 22 patients. The majority had pulmonary atresia (n = 9) or HLHS (n = 10). Their median age was 4 ms (range 10 days to 4 years) and median weight 4.9 kg (range 3–14). Nine had a central and 15 had a BT shunt with a median shunt size of 3.75 mm (range 3–6). The interval from shunt placement to intervention was 1.9 ms (range 4 days–3.8 years). The indication for intervention was increasing cyanosis in10 patients and delaying final repair in 9. Two patients were on ECMO at the time of intervention. The median shunt diameter increased from 2.3 to 4.1 mm and oxygen saturation from 72 to 85% (P < 0.001). No intra‐procedural complications were encountered. One patient died from aspiration (autopsy demonstrated a patent shunt), 13 progressed to repair or next stage, 6 remain palliated with shunts as they are deemed unfit for the next stage and 2 are awaiting surgery.ConclusionsStenting of systemic to pulmonary artery shunt is a safe and effective procedure and avoids surgical re‐intervention. It can be performed both as a rescue procedure in patients with acute shunt occlusion and as an elective procedure to palliate patients not yet suitable for subsequent corrective or staged repair. © 2015 Wiley Periodicals, Inc.
Dual [Fe+Phosphine] Catalysis: Application in Catalytic Wittig Olefination
Authors: Rommel Susanne , Belger Christian , Begouin Jeanne‐Marie , Plietker Bernd 
Published: April 2015

AbstractIron hydride complexes of the general formula P2Fe(NO)CO)H are highly active catalysts for the hydrosilylation of aldehydes or ketones and phosphine oxides. Depending on the solvent, the in situ reduction of the phosphine oxide can be faster than the corresponding hydrosilylation of a carbonyl group. This unusual activity was used within the context of catalytic Wittig olefination.
Multi‐Objective Optimization of Pseudo‐Dynamic Operation of Naphtha Pyrolysis by a Surrogate Model
Authors: Jin Yangkun , Li Jinlong , Du Wenli , Qian Feng 
Published: April 2015

AbstractA simple pseudo‐dynamic surrogate model is developed in the framework of the state space model with the feed‐forward neural network to replace the complex free radical pyrolysis model. The surrogate model is then applied to investigate the multi‐objective optimization of two key performance objectives with distinct contradiction: the mean yields of key products and the day mean profits. The ϵ‐constraint method is employed to solve the multi‐objective optimization problem, which provides a broad range of operation conditions depicting tradeoffs of both key objectives. The Pareto‐optimal frontier is successfully obtained and five selected cases on the frontier are discussed, suggesting that flexible operations can be performed based on industrial demands.
Generation and Deposition of Organic Nanoparticles in a Liquid Ring Pump
Authors: Brunn Claudia , Sinanis Sokratis , Mall‐Gleissle Susanne , Schaber Karlheinz 
Published: April 2015

AbstractA new method for the production of organic nanoparticles or nanosuspensions in a liquid ring vacuum pump is presented. A hot carrier gas charged under vacuum conditions with poorly water‐soluble organic substances is compressed and simultaneously cooled by the partially evaporating sealant water of the liquid ring vacuum pump. During compression and quenching, the gas‐vapor mixture becomes highly supersaturated and aerosol formation initiated by homogeneous nucleation occurs in the compression chambers between the impeller blades of the pump. The thus generated gas‐borne droplets or solid particles are mainly trapped and enriched in the sealant ring liquid, which is discharged, separated from the carrier gas in an external separator and returned to the pump. Experiments yielded aqueous nanosuspensions of insoluble organic substances with typical particle sizes between 50 and 300 nm, as well as foam in the external gas‐liquid separator. The foam showed stable structures due to incorporated solid nanoparticles.
A Cascade‐Reaction Nanoreactor Composed of a Bifunctional Molecularly Imprinted Polymer that Contains Pt Nanoparticles
Authors: Wang Jiao , Zhu Maiyong , Shen Xiaojuan , Li Songjun 
Published: April 2015

AbstractThis study was aimed at addressing the present challenge of cascade reactions, namely, how to furnish the catalysts with desired and hierarchical catalytic ability. This issue was addressed by constructing a cascade‐reaction nanoreactor made of a bifunctional molecularly imprinted polymer containing acidic catalytic sites and Pt nanoparticles. The acidic catalytic sites within the imprinted polymer allowed one specified reaction, whereas the encapsulated Pt nanoparticles were responsible for another coupled reaction. To that end, the unique imprinted polymer was fabricated by using two well‐coupled templates, that is, 4‐nitrophenyl acetate and 4‐nitrophenol. The catalytic hydrolysis of the former compound at the acidic catalytic sites led to the formation of the latter compound, which was further reduced by the encapsulated Pt nanoparticles to 4‐aminophenol. Therefore, this nanoreactor demonstrated a catalytic‐cascade ability. This protocol opens up the opportunity to develop functional catalysts for complicated chemical processes.
Multifold Fluorescence Enhancement in Nanoscopic Fluorophore–Clay Hybrids in Transparent Aqueous Media
Authors: Felbeck Tom , Mundinger Simon , Lezhnina Marina M. , Staniford Mark , Resch‐Genger Ute , Kynast Ulrich H. 
Published: April 2015

AbstractValuable emissive properties of organic fluorophores have become indispensable analytical tools in biophotonics, but frequently suffer from low solubilities and radiationless deactivation in aqueous media, that is, in biological ambience as well. In this report, nanoscaled dye–clay hybrids based on laponite, Na0.7{(Li0.3Mg5.5)[Si8O20(OH)4]}, are taken advantage of to solubilize neutral dyes, which are natively not encountered in water. Previously reported efficiency and solubility bottlenecks of such hybrids can to a large extent be overcome by comparably simple chemical measures, as demonstrated here for two prominent examples, the fluorescent dyes Nile Red and Coumarin 153. On controlled co‐adsorption of small bifunctional quaternary ammonium ions (Me3N+C2H5OH and Me3N+C2H5NH2) we observed an outright efficiency boost by an order of magnitude, and a 30‐fold brightness gain. Even at higher concentrations, transparency and stability of the hybrid dispersions are retained, rendering them useful for employment as optically functional nanoparticles in bioassays and beyond.
Facile Synthesis of Quasi‐One‐Dimensional Au/PtAu Heterojunction Nanotubes and Their Application as Catalysts in an Oxygen‐Reduction Reaction
Authors: Cai Kai , Liu Jiawei , Zhang Huan , Huang Zhao , Lu Zhicheng , Foda Mohamed F. , Li Tingting , Han Heyou 
Published: April 2015

AbstractAn intermediate‐template‐directed method has been developed for the synthesis of quasi‐one‐dimensional Au/PtAu heterojunction nanotubes by the heterogeneous nucleation and growth of Au on Te/Pt core–shell nanostructures in aqueous solution. The synthesized porous Au/PtAu bimetallic nanotubes (PABNTs) consist of porous tubular framework and attached Au nanoparticles (AuNPs). The reaction intermediates played an important role in the preparation, which fabricated the framework and provided a localized reducing agent for the reduction of the Au and Pt precursors. The Pt7Au PABNTs showed higher electrocatalytic activity and durability in the oxygen‐reduction reaction (ORR) in 0.1 M HClO4 than porous Pt nanotubes (PtNTs) and commercially available Pt/C. The mass activity of PABNTs was 218 % that of commercial Pt/C after an accelerated durability test. This study demonstrates the potential of PABNTs as highly efficient electrocatalysts. In addition, this method provides a facile strategy for the synthesis of desirable hetero‐nanostructures with controlled size and shape by utilizing an intermediate template.