bluuebunny/crossref_metadata_2025 huggingface dataset:
Inventando Chile: descalces y borraduras en la cartografía del territorio nacional desde las exposiciones universales
Authors:   , Maza Pezo Florencia de la
Published: April 2024

Inventando Chile se sitúa como una propuesta para mirar la historia (o historias) de Chile desde sus propios discursos. Utilizando la cartografía como metodología, se estudian y precisan los territorios que ha ido presentando el país en las exposiciones universales desde la forma y el contenido de sus muestras. Según la Bureau International des Expositions, la organización intergubernamental encargada de supervisar y regular estos eventos, Chile ha participado quince veces entre 1851 y 2020, ya sea sólo con una muestra o con una muestra acompañada de un pabellón. Los atributos físicos de las muestras y pabellones nacionales cargan siempre con discursos que remiten al territorio y, si bien, el límite político del país se suele considerar como un hecho fijo, estas representaciones no sólo dibujan porciones acotadas del país, sino que muchas veces ni siquiera coinciden con la cartografía “oficial”. Estudiar las exposiciones es una manera concreta de descomponer posturas territoriales y geopolíticas del país y cómo han cambiado con el tiempo; la cartografía permite esas nuevas asociaciones al abordar gráficamente cualquier tipo de fenómeno discursivo, de naturaleza concreta o abstracta. Cada discurso que ha adoptado Chile es indicativo de una temporalidad específica, en que, pese a que los intereses del país han variado, hay un tinte que se ha mantenido: la necesidad de asegurar su posición dentro del propio territorio y el mundo, asociándose a ciertos objetos y sistemas constructivos para mantener y aumentar su pertinencia. La investigación produce dos tipos de mapas: uno que abarca un encuadre ampliado (un zoom out) que presenta la escala máxima de lo representado; y otro que hace un acercamiento (un zoom in) que entra en detalles específicos de cada caso. En ambos priman enfoques distintos; los zoom out se centran en la posición geopolítica de Chile y su valor en el tablero mundial, mientras que el zoom in representa cómo Chile sostiene y visibiliza su propia soberanía en distintos fragmentos de su territorio. La invitación a mirar hacia atrás consiste en reconocer esos patrones de la fisonomía del territorio, que como total arman algo mayor.
Data envelopment analysis of operational efficiency in Chilean wine cellars
Authors:   , Hirmas Valderrama Isidora
Published: April 2024

El objetivo principal de esta investigacion es determinar y medir el nivel de compet- ´ itividad en las bodegas de vinedos en Chile, de manera de definir aquellas Vi ˜ nas cuyas ˜ bodegas representan eficiencia productiva segun el factor productivo a analizar, y aquellas ´ que presentan oportunidades de mejora en su proceso productivo. Para lograrlo, en primer lugar se realiza una revision de la literatura actual en donde ´ vemos las distintas aplicaciones y potenciales que representa la optimizacion de envoltura ´ de datos (DEA) y como este m ´ etodo d eoptimziaci ´ on no ha sido aplicado en Chile. Luego, ´ procedemos a explicar la metodolog´ıa a utilizar en los diferentes analisis dentro de esta ´ investigacion, explicando la l ´ ogica matem ´ atica detr ´ as de DEA y sus beneficios. ´ Finalmente se describen los resultados de cada analisis realizado: an ´ alisis descriptivo ´ de las variables, analisis general de eficiencia incluyendo el desarrollo de KPIs para el ´ proceso productivo de vino, clusterizacion con k-means y por ´ ultimo el an ´ alisis de en- ´ voltura de datos (DEA). Dentro de los resultados principales se encuentra la construccion´ de fronteras eficientes para cada factor productivo: costo, eficiencia en recursos humanos y eficiencia en infraestructura, las cuales permitieron identificar visualmente las bodegas eficientes y aquellas que quedaban dentro de la frontera representan oportunidades de mejora. Lo interesante es que la oportunidad de mejora puede o no ser muy diferente para cada bodega, ya que depende principalmente de quien elije como ”peer” o bodega de ´ referencia. Considerando la combinacion de los diferentes an ´ alisis realizados, logramos no solo ´ confirmar las hipotesis de la investigaci ´ on sino que adicionalmente fue posible la creaci ´ on´ xiv de tres nuevas categor´ıas para clasificar las bodegas de los vinedos en Chile. En conse- ˜ cuencia, cada categor´ıa describe la situacion productiva a la que se enfrenta la bodega y ´ por ende, una recomendacion general respecto a la gesti ´ on de operaciones del proceso pro- ´ ductivo de esa categor´ıa. Adicionalmente, para cada Vina que particip ˜ o de este estudio, ´ se incluyo una recomendaci ´ on personalizada considerando la categor ´ ´ıa a la que pertenece junto con sus resultados espec´ıficos en los analisis anteriores.
Neuroimaging Manifestations and Clinical Correlates of Japanese Encephalitis: Insights from an MRI Case Series
Authors: Hussain Ameer , Rubben Ajay Lucas , Raj Vishnu
Published: April 2024

Japanese Encephalitis (JE) poses a significant public health threat across Asia and the Western Pacific, leading to considerable mortality and morbidity if not promptly diagnosed and treated. This flaviviral infection, transmitted by Culex mosquitoes, primarily affects children but can impact individuals of all ages. Prompt diagnosis relies on detecting Japanese Encephalitis Virus (JEV) IgM antibodies in serum or Cerebrospinal Fluid (CSF), alongside characteristic Magnetic Resonance Imaging (MRI) findings. In this MRI case series, three confirmed cases of JE are presented, showcasing the typical neuroimaging manifestations observed in affected individuals. All cases exhibited bilateral thalamic hyperintensities on T2-weighted and Fluid Attenuated Inversion Recovery (FLAIR) images, a hallmark feature of JE. Additionally, one patient demonstrated involvement of the substantia nigra and bilateral frontal cortex. The clinical implications of present study findings underscore the importance of considering JE as a differential diagnosis in patients presenting with symptoms of encephalitis, especially when MRI reveals bi-thalamic signal alterations. Early recognition and initiation of appropriate treatment, including antiviral agents, are crucial for improving outcomes and reducing mortality. This study contributes to the existing literature by reinforcing the importance of neuroimaging in diagnosing JE and highlighting the distinct MRI patterns associated with the disease. Recognising these characteristic imaging features can aid clinicians in promptly identifying and managing JE cases, thereby mitigating the associated morbidity and mortality.
Development and Evaluation of Different Formulations of Nomuraea rileyi (Farlow) Samson against Spodoptera litura (Fabricius)
Authors: S. H Rashmi , S. H Ramanagouda , Venkateshalu . , T. N Sachinkumar
Published: April 2024

The 26 different formulations of Nomuraea rileyi (Farlow) Samson were developed and tested against third instar larvae of Spodoptera litura (Fabricius). The experiment was conducted at Bio control laboratory, Department of Entomology, Kittur Rani Chanamma College of Horticulture (KRCCH), Arabhavi. Among all formulations tested, the groundnut oil and combination of groundnut oil + rice grain formulations recorded cent per cent mortality of S. litura at seven days of treatment. The percent mean mortality was 83.33, 80.00, 73.33 and 73.33 per cent in groundnut oil, combination of groundnut oil + rice grain, mustard oil + rice grain and groundnut oil + wheat grain, respectively.
Enhanced Photorefractivity of Poly(N‐vinylcarbazole)‐Based Composites through Electric‐Field Treatments and Ionic Liquid Doping
Authors: Quintana José A. , Villalvilla José M. , Boj Pedro G. , Martín‐Gomis Luis , Ortiz Javier , Fernández‐Lázaro Fernando , Sastre‐Santos Ángela , García María A. Díaz
Published: January 2009

It is shown that the photorefractive (PR) performance of polymer composites based on poly(N‐vinylcarbazole) can be improved when samples are subjected to an electric field for a certain time, i.e. conditioned, previous to the PR characterization. It is also found that for conditioned samples the addition of an organic ionic liquid to the PR composition allows to obtain PR effect without the need of using a sensitizer. The typical electric field treatment time at room temperature and at a field of 20 V µm−1is 20 min. This procedure leads to a decrease of dark conductivity and an increase of photoconductivity, and consequently an increase of conductivity contrast. This results in higher PR two‐beam‐coupling gain coefficients and shorter response times, particularly at low fields. Dependencies of the process dynamics on impurities, applied field strength, temperature and the presence of an organic ionic liquid are examined in detail. It is remarkable the significant increase of the PR gain coefficients, and more drastically of the net gain coefficients, observed at low fields (<55 V µm−1), when an ionic organic liquid such as benzalkonium chloride is added to unsensitized conditioned PR composites. These findings open a new route to improve the PR performance, not only of PVK‐based composites, but also of other types of organic materials, the main advantage being that no sensitizer is needed.
Design and prevention
Authors: Renfrew Charles B.
Published: January 2009

CPR Board Chairman Charles B. Renfrew, of San Francisco, writes that the focus will now be on tailoring processes, and preventing disputes.
More changes coming
Authors: Henry James F.
Published: January 2009

CPR Institute founder James F. Henry, of Waccabuc, N.Y., discusses how the changes ADR has produced inlegal practice indicate that more are on the way, probably in the justice system itself.
Reactive Intermediates in Oxygenation Reactions with Mononuclear Nonheme Iron Catalysts
Authors: Yoon Jihae , Wilson Samuel A. , Jang Yu Kyeong , Seo Mi Sook , Nehru Kasi , Hedman Britt , Hodgson Keith O. , Bill Eckhard , Solomon Edward I. , Nam Wonwoo
Published: January 2009

Eine späte Zwischenstufe: Der Nichthäm‐Eisen(IV)‐Oxo‐Komplex [FeIV(O)(bqen)(L)]n+ (bqen=N,N′‐Dimethyl‐N,N′‐bis(8‐chinolyl)ethan‐1,2‐diamin, L=CH3CN oder CF3SO3−) aktiviert die C‐H‐Bindungen von Alkanen und Alkoholen durch Wasserstoffatomabstraktion. Die katalytische Oxidation dieser Spezies soll durch eine bei Oxidationsreaktionen hoch aktive Nichthäm‐Eisen(V)‐Oxo‐Spezies erfolgen (siehe Bild).

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High‐Yielding Synthesis of the Anti‐Influenza Neuramidase Inhibitor (−)‐Oseltamivir by Three “One‐Pot” Operations
Authors: Ishikawa Hayato , Suzuki Takaki , Hayashi Yujiro
Published: January 2009

Abkürzungen genommen: Eine bemerkenswert kurze und ergiebige asymmetrische Totalsynthese von (−)‐Oseltamivir beruht auf organokatalytischen Umsetzungen und Dominoreaktionen. Die als Tamiflu bekannte Zielverbindung wird in kurzer Zeit effizient erhalten, und auch Derivate können effektiv synthetisiert werden.

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Sequential Assembly of Phototunable Ferromagnetic Ultrathin Films with Perpendicular Magnetic Anisotropy
Authors: Suda Masayuki , Einaga Yasuaki
Published: January 2009

Geordnete Verhältnisse: Assoziate ferromagnetischer FePt‐Nanopartikel mit großer senkrechter magnetischer Anisotropie wurden durch magnetfeldgestützte schichtweise Abscheidung erhalten, und anschließend wurden geschichtete Filme aus L10‐FePt‐Nanopartikeln und organischen Polymeren hergestellt. Diese Filme werden bei der Verwendung photochromer Moleküle als Polymerschichten photodurchstimmbar.

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Dicationic Sulfur Analogues of N‐Heterocyclic Silylenes and Phosphenium Cations
Authors: Martin Caleb D. , Jennings Michael C. , Ferguson Michael J. , Ragogna Paul J.
Published: January 2009

S2+ in der Stickstoffzange: Schwefel(II)‐Dikationen lassen sich mithilfe von α‐Diiminen erhalten, die die positive Ladung stabilisieren (siehe Schema; DAB=Diazabutadien, Dipp=2,6‐Diisopropylphenyl, OTf=CF3SO3). Die Bindungssituation entspricht am ehesten der eines N,N‐koordinierten Schwefel(II)‐Dikations; diese Spezies sind die ersten Schwefel‐Strukturmimetika N‐heterocyclischer Silylenverbindungen und Phospheniumkationen.

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Enantioselective Intermolecular Crossed‐Conjugate Additions between Nitroalkenes and α,β‐Enals through a Dual Activation Strategy
Authors: Zhong Cheng , Chen Yunfeng , Petersen Jeffrey L. , Akhmedov Novruz G. , Shi Xiaodong
Published: January 2009

Doppelt schön: Die Titelreaktion wurde mithilfe einer Kombination aus Lewis‐Basen‐ und Iminium‐Aktivierung entwickelt (siehe Schema). Sie verläuft mit ausgezeichneten Ausbeuten und ee‐Werten, und die Produkte können zudem mit ausgezeichneter Erhaltung der Konfiguration in Einzelenantiomere eines substituierten Pyrrolidins überführt werden.

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Photoresponsive Cyclodextrin‐Covered Nanocontainers and Their Sol‐Gel Transition Induced by Molecular Recognition
Authors: Park Chiyoung , Lee Kyuho , Kim Chulhee
Published: January 2009

Springing the trap: Cyclodextrin‐covered mesoporous silica nanoparticles with photocleavable linkers exhibit photoinduced release characteristics and a sol–gel transition that is induced by molecular recognition (see picture). Upon exposure to UV light, the guest molecules were released from the pore by removal of the CD “gatekeeper”, which was linked on the surface of the silica nanoparticle through a photocleavable o‐nitrobenzyl ester moiety.

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High‐Yielding Synthesis of the Anti‐Influenza Neuramidase Inhibitor (−)‐Oseltamivir by Three “One‐Pot” Operations
Authors: Ishikawa Hayato , Suzuki Takaki , Hayashi Yujiro
Published: January 2009

Taking shortcuts: A remarkably short and high‐yielding asymmetric total synthesis of (−)‐oseltamivir takes advantage of organocatalysis and single‐pot domino operations. The target, known as the drug Tamiflu, is prepared efficiently in a short time, and also its derivatives can be synthesized effectively.

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Sequential Assembly of Phototunable Ferromagnetic Ultrathin Films with Perpendicular Magnetic Anisotropy
Authors: Suda Masayuki , Einaga Yasuaki
Published: January 2009

Getting organized: Assemblies of ferromagnetic FePt nanoparticles were generated with large perpendicular magnetic anisotropy by a magnetic‐field‐assisted layer‐by‐layer method, and subsequently layer‐by‐layer films consisting of L10‐FePt nanoparticles and organic polymers were prepared. These films are phototunable when photochromic molecules are used as polymer layers.

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Synthesis and polymerization of novel epoxy compounds having an adamantane ring and evaluation of their heat resistance and transparency
Authors: Maehara Takayuki , Takenaka Junji , Tanaka Kenji , Yamaguchi Masao , Yamamoto Hiromasa , Ohshita Joji
Published: January 2009

Three adamantane derivatives substituted by epoxy groups, 1,3‐bis(glycidyloxy)adamantane (2a), 5,7‐dimethyl‐1,3‐bis(glycidyloxy)adamantane (2b), 1,3,5‐tris(glycidyloxy)adamantane (2c), were synthesized from the corresponding adamantanediol or triol in good yields. These three epoxy compounds were polymerized with an acid anhydride, and the heat resistance of the resulting resins was evaluated. The resin prepared from 2c exhibited high heat resistance with the glass transition temperature (Tg) of 208°C and low degree of coloring by heating. The epoxy compounds were also found to be potentially useful as the precursors of high heat‐resistant resins by thermal homopolymerization. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
New polymer syntheses, Part 43: Novel polyamides‐based diarylidenecyclopentanone: Synthesis, characterization, and corrosion inhibition behavior
Authors: Aly Kamal I. , Wahdan Mostafa H. , Hussein Mahmoud A.
Published: January 2009

A new interesting class of polyamides containing diarylidenecyclopentanone moiety IIIa–f was synthesized by polycondensation reaction of the new diamino arylidene monomer I with different aliphatic and aromatic diacid chlorides (including adipoyl, sebacoyl, oxaloyl, terephthaloyl, isophthaloyl, biphenyldicarbonyl) and LiCl anhydrous as a catalyst at room temperature in NMP. The model compound II was synthesized by the interaction of one mole of diarylidenecyclopentanone monomer I with two moles of benzoyl chloride in NMP/LiCl at room temperature. The structure of the model compound was confirmed by correct elemental and spectral analyses. The resulting polymers were characterized by elemental and spectral analyses, beside solubility and viscometry measurements. The thermal properties of those polymers were evaluated by TGA, DTG, and DTA measurements and correlated to their structural units. X‐ray analysis showed that polymers having high degree of crystallinity in the region 2θ = 5 − 60°. In addition, the UV‐visible spectra of some selected polymers were measured in DMSO solution and showed absorption bands in the range 260 − 475 nm, due to n − π* and π − π* transition. On the other hand, the corrosion inhibition behavior of selected examples of polyamides was carried out on carbon–steel in 0.5M H2SO4 at 40°C. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Characterization of associating hydrogels of poly(vinyl alcohol) and poly(vinyl pyrrolidone)
Authors: Liu X. , Fussell G. , Marcolongo M. , Lowman A. M.
Published: January 2009

In this study, hydrogels were prepared from blends of poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP). The miscibility of the polymers was confirmed with differential scanning calorimetry with the appearance of a single glass‐transition temperature. Additionally, a negative Flory–Huggins interaction parameter further verified the interaction between PVA and PVP. We evaluated the stability of the hydrogels by swelling the gels in phosphate‐buffered saline solutions at pH 7.4. With attenuated total reflectance‐Fourier transform infrared spectroscopy, it was determined that, during swelling, PVP dissolved out of the gel over time and the equilibrium gel content of PVP was nearly identical in all of the samples investigated. After the dissolution of PVP, the equilibrium water content of the gels ranged from 64 to 76 wt %. Additionally, rubber elasticity studies were performed to elucidate information about the physically crosslinked network structure. As determined from rubber elasticity experiments, the mesh size of the physically crosslinked hydrogels ranged from 90 to 230 Å. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effects of alkalization and fiber loading on the mechanical properties and morphology of bamboo fiber composites. II. Resol matrix
Authors: Das Mahuya , Chakraborty Debabrata
Published: January 2009

Resol resin composites reinforced with alkali‐treated bamboo strips were fabricated with a hand‐lay‐up technique. This study was aimed at the evaluation of the influence of the caustic concentration on the mechanical properties of bamboo‐strip‐reinforced resol composites with a constant 50% loading of the reinforcement. The treatment of bamboo fiber in a solution of sodium hydroxide with increasing concentration percentages resulted in more and more rigid composites; as a result, the strength and modulus values exhibited improvements. The maximum improvement in the properties was possibly achieved with 20% caustic treated reinforcements. An infrared study indicated the formation of aryl alkyl ether with OH groups of cellulose and methylol groups of resol. Beyond 20%, there was degradation in all the strength properties due to the failure of the mechanical properties of the reinforcement itself. A correlation was found to exist between the mechanical properties and the morphology that developed. Another set of composites with variable loadings of 20% alkali treated fiber (40, 50, and 60%) was fabricated, and a 60% fiber loading showed the best mechanical properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and water absorbency of polyampholytic hydrogels with antibacterial activity
Authors: Li Xiaohong , Dong Qinzheng , He Peixin
Published: January 2009

Amphoteric terpolymers of acrylic acid (AA), acrylamide (AM), and N,N′‐dimethyl‐N‐ethylmeth‐acryloxylethylammoniumbromide (DMAEA‐EB) with varied compositions P[AA‐AM‐(DMAEA‐EB)] were synthesized by inverse suspension polymerization. The components of P[AA‐AM‐(DMAEA‐EB)] were verified by FTIR spectroscopy. The water absorption ability and antibacterial activity of the copolymer against Escherichia coli(E. coli) and Staphylococcus hyicus(S. hyicus) suspended in sterilized physiological saline were investigated. The introduction of N+R4 may increase the water absorbency of P[AA‐AM‐(DMAEA‐EB)] in some degree because of the excellent hydrophilicity of N+R4. The AA‐AM‐(DMAEA‐EB) hydrogels exhibited high antibacterial activity against bacteria tested. The process of adsorption between live bacteria cells and resins was at least partially reversible. A peak of antibacterial efficiency existed with increasing contact time. The resin killed 96.6% E. coli organisms and 90.3% S. hyicus organisms, respectively, within 30 min of contact at dosage of 0.1g. The concentration of DMAEA‐EB has a special effect on the antibacterial activity of the polyampholytic hydrogels, which is different from polycation. It was observed that the antibacterial activity of the resin with 2 mol % of DMAEA‐EB is superior to the copolymers tested with other compositions. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Thermal degradation behavior of styrene‐butadiene‐styrene tri‐block copolymer/multiwalled carbon nanotubes composites
Authors: Lu Lan , Yu Haiyang , Wang Shifeng , Zhang Yong
Published: January 2009

The thermal degradation behavior of styrene‐butadiene‐styrene triblock copolymer (SBS) and SBS/multiwalled carbon nanotubes (MWCNTs) composites prepared by solution processing and melt mixing, respectively, was investigated using nonisothermal thermogravimetric analysis (TGA). The kinetic parameters of the activation energy (Ea) for degradation, preexponential factor A, and the reaction order (n) were evaluated by the Flynn‐Wall‐Ozawa, Kissinger, and Coats‐Redfern methods, respectively. Ea increased and n decreased after the incorporation of 3 wt % of MWCNTs into the SBS. The Ea of SBS/MWCNTs composite prepared by melt mixing was higher than that by solution processing, which was attributed to the good dispersion of MWCNTs in SBS and the interactions between MWCNTs and SBS. The gases evolved during thermal degradation at a nitrogen atmosphere were studied by Fourier transform infrared spectroscopy (FTIR) coupled with the TGA. Aliphatic and aromatic CH peaks appeared simultaneously in FTIR spectra, indicating the thermal degradation of SBS proceeds by a random chain scission process. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Sisal chemo‐thermomechanical pulp paper with a strongly hydrophobic surface coating produced by a pentafluorophenyldimethylsilane cold plasma
Authors: Navarro Fernando , Dávalos Florentina , González‐Cruz Ricardo , López‐Dellamary Fernando , Manríquez Ricardo , Turrado José , Ramos Juan
Published: January 2009

Fluorinated thin layers were created on CTMP sisal and filter paper surfaces by using pentafluorophenyldimethylsilane (PFPDMS) under RF‐plasma conditions. Surface wettability and water absorption of unmodified and modified samples of both materials were evaluated through contact angle and Cobb test techniques, respectively. The mechanical strength and optical properties were also analyzed. The surface functional groups produced were evaluated using X‐ray photoelectron spectroscopy, Electron Spectroscopy for Chemical Analysis (ESCA) and Attenuated Total Reflectance Fourier Transform infrared (ATR FT‐IR) spectroscopy. Surface morphological changes after plasma treatment were evaluated using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). PFPDMS‐plasma treatment of sisal CTMP reduced water absorption from more than 400 g (H2O)/m2 to 18 g (H2O)/m2. The contact angle was increased from less than 15° to 119°–134°. Water absorption for untreated filter paper was 220 g (H2O)/m2 and after plasma treatment the value decreased to 13.6 g (H2O)/m2. Water drop contact angle for untreated filter paper was 24°, and after PFPDMS‐plasma treatment it was 134°. Strength properties were slightly reduced in some cases and brightness was reduced in most of the trials, turning to yellow. ATR FT‐IR and ESCA spectroscopy indicated a fluorinated aromatic surface, whereas AFM and SEM showed a smooth surface coating for both sisal and filter paper after PFPDMS‐plasma treatment. A fully coated surface with a very high hydrophobic character was observed. This new property can be attributed to the formation of a crosslinked polymer network of covalently bound PFPDMS‐based units on the paper surface as shown by the presence of CSi, COSi, CCFx, and CF bonds. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and characterization of poly(carbonate urethane) networks with shape‐memory properties
Authors: Feng Yakai , Xue Yan , Guo Jintang , Cheng Lei , Jiao Licai , Zhang Yu , Yue Jinlong
Published: January 2009

In this study, a series of shape‐memory polyurethanes were prepared from polycarbonate diol (PCDL) with a molecular weight of 2000, trimethylol propane, and isophorone diisocyanate (IPDI). The properties of crosslinked poly(carbonate urethane) (PCU) networks with various compositions were investigated. The chemical structures and thermal properties were determined with Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. FTIR analysis indicated that PCU had the structures of IPDI and PCDL and the amido formyl ester in polyurethanes. The gel content of PCU showed that PCU could be effectively formed as crosslinked polyurethane networks. The glass‐transition temperatures of the PCU networks increased slightly with decreasing soft‐segment content in the networks. The values of Young's modulus in the networks at 25°C increased with decreasing soft‐segment content, whereas the tensile stress and breaking elongation decreased significantly. PCU showed shape‐memory effects with a high strain fixity rate. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
LnNa8[OC(CH3)3]10(OH) alkoxide clusters: Highly active single‐component catalysts for the homopolymerization and copolymerization of ε‐caprolactone and trimethylene carbonate
Authors: Sheng Hongting , Li Junmei , Yao Yong Zhang Yingming , Shen Qi
Published: January 2009

Heterometal alkoxide clusters of lanthanide and sodium, LnNa8[OC(CH3)3]10(OH) [where Ln = Nd (1) or Yb (2)], which were synthesized by the metathesis reaction of LnCl3 with NaOC(CH3)3 and NaOH in a 1 : 10 : 1 molar ratio in high yields and fully characterized including X‐ray analysis for 2, were found to be highly active catalysts in the ring‐opening polymerization of ε‐caprolactone and trimethylene carbonate and their copolymerization. All of the polymers obtained showed a unimodal molecular weight distribution, indicating that 1 and 2 could really be used as single‐component catalysts. The dependence of catalytic activity on the lanthanide metals was observed: Yb < Nd. A coordination–insertion mechanism for the ring‐opening polymerization is proposed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Characterization and evaluation of supported rac‐dimethylsilylenebis(indenyl)zirconium dichloride on ethylene polymerization
Authors: Franceschini Fernando C. , Tavares Tatiana T. da R. , Bianchini Daniela , Alves Maria do Carmo M. , Ferreira Maria Lujan , dos Santos João H. Z.
Published: January 2009

rac‐Dimethylsilylenebis(indenyl)zirconium dichloride was grafted onto commercial methyl aluminoxane modified silica (SMAO) at different loadings (0.1–1.5 wt % Zr/SMAO). Supported catalysts were evaluated in ethylene polymerization with isoprenylaluminum as a cocatalyst. The characterization of two supported catalysts bearing 0.3 and 0.8 wt % Zr/SiO2 by extended X‐ray absorption fine structure indicated that the number and the intensity of the peaks beyond the coordination shell, associated with the next nearest neighbors, depended on the Zr concentration. For the catalyst with a higher Zr content, only one peak (2.8 Å) was observed. The catalyst with 0.3 wt % Zr/SMAO presented two small peaks at 2.8 and 3.8 Å. Polymers produced with the supported catalysts presented lower crystallinity and higher molar mass and polydispersity values in comparison to that produced by the homogeneous one. Gel permeation chromatogram deconvolution suggested the presence of four catalyst sites for the supported systems. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and characterization of composite membranes of polysulfone and microcrystalline cellulose
Authors: Zhang Liping , Chen Guowei , Tang Huanwei , Cheng Qingzheng , Wang Siqun
Published: January 2009

Physical and chemical modifications of polymeric ultrafiltration membranes are necessary to improve their hydrophilic properties, strength, and other characteristics. Microcrystalline cellulose (MCC) was prepared from cellulose pulp by acid‐catalyzed hydrolysis in the presence of ultrasonic radiation, and the properties of MCC were evaluated. Through the addition of MCC to a polysulfone (PS) membrane solution, a casting solution of a PS/MCC blend was obtained. Subsequently, the ultrafiltration membrane from the blend was further developed in a phase‐inversion process comprising immersion and deposition. The capacity for ultrafiltration was better with increasing MCC content. When the ratio of MCC to PS was 0.3, the pure water flux of the composite membrane reached 234.2 L/m2/h, and the retention of a bovine serum albumin solution (1 g/L) was as high as 93.4%. The membranes were also observed with scanning electron microscopy and atomic force microscopy to study their microstructures. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Development of redox‐mediated oxysilane sol–gel biosensors on carbon‐film electrode substrates
Authors: Pauliukaite Rasa , Gouveia‐Caridade Carla , Liess Hans Dieter , Brett Christopher M. A.
Published: January 2009

Three types of carbon‐film electrodes, made from electrical resistors with 1.5‐, 15‐, and 140‐Ω nominal resistances, were used to develop redox‐mediated sol–gel biosensors, and the results were compared with those from previously investigated 2‐Ω carbon‐film electrodes. Two different redox mediators, copper hexacyanoferrate and poly(neutral red), were deposited onto the carbon‐film electrodes, with the latter showing good electrochemical properties for electroanalytical applications, which were best on electrodes made from 15‐Ω carbon‐film resistors. It was not possible to deposit mediator film on the carbon‐film resistor electrodes of 140‐Ω nominal resistance. Glucose oxidase was immobilized on poly(neutral red) modified electrodes with sol–gel encapsulation from a mixture of 3‐glycidoxypropyltrimethoxysilane and methyltrimethoxysilane precursors at a volume ratio of 2 : 1. The best sensor electrochemical properties and response to glucose in model solution were found with electrodes constructed from 15‐Ω resistors, although the stability under the same conditions was better in the biosensors constructed with 2‐Ω nominal resistance electrodes. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
N‐Benzylsalicylthioamides: Highly Active Potential Antituberculotics
Authors: Doležal Rafael , Waisser Karel , Petrlíková Eva , Kuneš Jirí , Kubicová Lenka , Machácek Miloš , Kaustová Jarmila , Dahse Hans Martin
Published: January 2009

A gseries of 29 new derivatives of N‐benzylsalicylthioamides was synthesized and the compounds were tested for in‐vitro antimycobacterial activity against Mycobacterium tuberculosis, Mycobacterium kansasii, and Mycobacterium avium. The activity was analyzed by quantitative structure‐activity relationship (QSAR). Activity increased with increasing lipophilicity and electron donating effect of the substituents in the acyl moiety and decreased with the electrophilic superdelocalizability of the molecules. The most active compounds are more active than isoniazid (INH) and are active against INH‐resistant potential pathogenic strains of mycobacterium.
Iron and Ruthenium Nanoparticles in Carbon Prepared by Thermolysis of Buckymetallocenes
Authors: Nakae Takahiro , Matsuo Yutaka , Takagi Masatoshi , Sato Yuta , Suenaga Kazu , Nakamura Eiichi
Published: January 2009

Turn up the heat! Iron and ruthenium nanoparticles in carbon have been prepared by thermolysis of iron and ruthenium fullerene complexes at 500–900 °C in nitrogen. Differences in their size, formation processes, and catalytic activities have been characterized using TG‐DTA, VT‐TEM, and VT‐XRD analyses.

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Thermolysis of fullerene iron and ruthenium complexes (buckymetallocene M(C60R5)Cp (M=Fe; R=Ph (1) and Me (2), M=Ru; R=Ph (3), Me (4)) under a nitrogen atmosphere produced metal nanoparticles dispersed in carbon materials. The thermal degradation processes of the buckymetallocenes were studied by TG‐DTA, TEM with a heating sample stage, and VT‐XRD. Variation of the thermolysis temperature led to a change in the size of the nanoparticles and the morphology of the carbon materials. Thermolysis of buckyferrocene at 700 °C gave highly dispersed iron nanoparticles (average diameter of 7.4 nm). After thermal treatment at 900 °C, graphite structures such as carbon nanocapsules and carbon nanotubes formed because of the catalytic activity of the iron nanoparticles. Ruthenium nanoparticles prepared from buckyruthenocene were much smaller than the iron counterparts, and did not catalyze the formation of graphite structures. When buckyruthenocene absorbed on silica gel was heated at 500 °C under a hydrogen atmosphere, the resulting ruthenium nanoparticles showed high activity in catalytic hydrogenation.
Speckle observations with PISCO in Merate: VI. Astrometric measurements of visual binaries in 2006
Authors: Scardia M. , Prieur J.‐L. , Pansecchi L. , Argyle R.W. , Sala M.
Published: January 2009

We present relative astrometric measurements of visual binaries made during the second semester of 2006, with the speckle camera PISCO at the 102 cm Zeiss telescope of Brera Astronomical Observatory, in Merate. Our sample contains orbital couples as well as binaries whose motion is still uncertain. We obtained 175 new measurements of 169 objects, with angular separations in the range 0″.1–4″.2, and an average accuracy of 0″.01. The mean error on the position angles is 0°.6. Most of the position angles could be determined without the usual 180° ambiguity with the application of triplecorrelation techniques and/or by inspection of the long integration files.We also present the new orbits we have computed for ADS 11479, 11584 and 16538, for which our measurements lead to large residuals and/or for which the revision was justified by the significant number of observations made since the last orbit computation (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The FIRST radio survey: Panchromatic properties of FIRST radio sources identified in the Boötes and Cetus fields
Authors: Bouchefry K. El
Published: January 2009

In this paper the availability of multi‐wavelength optical/infrared information of FIRST (Faint Images of the Radio Sky at 20 cm) radio sources counterparts over ∼9.2 deg2 in the Boötes field and ∼2.4 deg2 in the Cetus field is exploited to infer the physical properties of the faint radio population. The radio sources optically identified have been divided into resolved galaxies and stellar‐like objects finding that the faint radio population is mainly composed of early‐type galaxies with very red colour (Bw – R ∼ 4.6). A total number of 57 counterparts of FIRST radio sources have extremely red colour (R – K ≥ 5). Photometric redshift from Hyperz implies that the Extremely Red Objects (EROs) counterparts to FIRST radio sources are mostly located in the range z = 0.7–2, with the bulk of the population at z ∼ 1. Taking advantage of the near infrared imaging with FLAMEX (FLAMINGOS Extragalactic Infrared Survey), the EROs counterparts to FIRST radio sources are separated into passively‐evolving and dusty star‐forming galaxies using their RJK colours; the relatively blue J – K of these galaxies suggest that most are old elliptical galaxies (18/25) rather than dusty starburst galaxies (7/25). A total of 15 Distant Red Galaxy (DRGs) have been identified as counterparts to FIRST radio sources in the Cetus field and 3 DRGs in the Boötes field with J – K > 2.3 (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A catalogue of stars suspected of bright active regions
Authors: Zboril M.
Published: January 2009

We present a catalogue of field stars across the HR diagram suspected of bright active regions in their atmospheres.We aim at developing the first version of a database of active stars with bright regions (bright spots). Using a variety of databases and the internet we found and gathered all relevant archival data starting about 1973 and being important for developing such a catalogue. We found that the phenomenon starspot is now common to a variety of spectral type and luminosity classes. Our primary goal was to identify active solar and late type stars suspicious of bright active regions but the search offers expanded results including young T Tauri stars, eclipsing binaries with equal or mixed spectral types components (Algols,WUMa stars) and in some cases other types of objects. Moreover, the light curves analyses for eclipsing binaries offer reliable estimates for spot properties and it was found that 20% of binaries in the catalogue had a spot located near the L point (neck zone). At present, the catalogue consists of 134 stars and overall characteristics for them are organised in several files in ASCII format. The catalogue is electronically available (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The chromospherically active binary star EI Eridani: I. Absolute dimensions
Authors: Washuettl A. , Strassmeier K.G. , Granzer T. , Weber M. , Oláh K.
Published: January 2009

We present a detailed determination of the astrophysical parameters of the chromospherically active binary star EI Eridani. Our new radial velocities allow to improve the set of orbital elements and reveal long‐term variations of the barycentric velocity. A possible third‐body orbit with a period of ≈19 years is presented. Absolute parameters are determined in combination with the Hipparcos parallax. EI Eri's inclination angle of the rotational axis is confined to 56°.0 ± 4°.5, ist luminosity class IV is confirmed by its radius of 2.37 ± 0.12 R⊙. A comparison to theoretical stellar evolutionary tracks suggests a mass of 1.09 ± 0.05 M⊙ and an age of ≈ 6.15 Gyr. The present investigation is the basis of our long‐term Doppler imaging study of its stellar surface (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tayler instability with Hall effect in young neutron stars
Authors: Rüdiger G. , Shalybkov D.A. , Schultz M. , Mond M.
Published: January 2009

Collapse calculations indicate that the hot young neutron stars rotate differentially so that strong toroidal magnetic field components should exist in the outer shell where also the Hall effect appears to be important when the Hall parameter $ \hat \beta $ = ωBτ exceeds unity. The amplitudes of the induced toroidal magnetic fields are limited by the current‐induced Tayler instability. An important characteristics of the Hall effect is its distinct dependence on the sign of the magnetic field. We find for fast rotation that positive (negative) Hall parameters essentially reduce (increase) the stability domain. It is thus concluded that the toroidal field belts in young neutron stars induced by their differential rotation should have different amplitudes in both hemispheres which later are frozen in. Due to the effect of magnetic suppression of the heat conductivity also the brightness of the two hemispheres should be different. As a possible example for our scenario the isolated neutron star RBS 1223 is considered which has been found to exhibit different X‐ray brightness at both hemispheres (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Determining the character of motion in quiet and active galaxies with a satellite companion
Authors: Caranicolas N.D. , Innanen K.A.
Published: January 2009

A galaxy model with a satellite companion is used to study the character of motion for stars moving in the x ‐y plane. It is observed that a large part of the phase plane is covered by chaotic orbits. The percentage of chaotic orbits increases when the galaxy has a dense nucleus of massMn. The presence of the dense nucleus also increases the stellar velocities near the center of the galaxy. For small values of the distance R between the two bodies, low energy stars display a chaotic region near the centre of the galaxy, when the dense nucleus is present, while for larger values of R the motion in active galaxies is regular for low energy stars. Our results suggest that in galaxies with a satellite companion, the chaotic character of motion is not only a result of galactic interaction but also a result caused by the dense nucleus. Theoretical arguments are used to support the numerical outcomes. We follow the evolution of the galaxy, as mass is transported adiabatically from the disk to the nucleus. Our numerical results are in satisfactory agreement with observational data from M51‐type binary galaxies (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Kinematics and metallicity analysis for nearby F, G and K stars
Authors: Vidojević S. , Ninković S.
Published: January 2009

A sample containing 1 026 stars of spectral types F, G, and K, mainly dwarfs, from the solar neighbourhood with available space velocities and metallicities is treated. The treatment comprises a statistical analysis of the metallicity and velocity data and calculation of galactocentric orbits. Sample stars identified as members of the galactic halo are detached from the rest of the sample based on the values of their metallicities, velocity components and galactocentric orbits. In identifying halo stars a new, kinematical, criterion is proposed. Except one, these halo stars are the metal‐poorest ones in the sample. Besides, they have very high velocities with respect to LSR. On the other hand, the separation between the thin disc and thick one is done statistically based on LSR space velocities, membership probability (Schwarzschild distribution with assumed parameters) and galactocentric orbits. In the metallicity these two groups are not much different. For each of the three subsamples the mean motion and velocity ellipsoid are calculated. The elements of the velocity ellipsoids agree well with the values found in the literature, especially for the thin disc. The fractions of the subsystems found for the present sample are: thin disc 93%, thick disc 6%, halo 1%. The sample stars established to be members of the thin disc are examined for existence of star streams. Traces of both, known and unknown, star streams are not found (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The spectroscopic evolution of V2467 Cyg (Nova Cygni 2007) in the first months after the outburst
Authors: Poggiani R.
Published: January 2009

We present the spectroscopy of nova V2467 Cyg acquired at the Loiano Observatory, Italy, during the first six months after the outburst. We have used the optical spectroscopy to study the physical properties of the ejected material and the photometry to estimate the nova distance. V2467 Cyg is a fast nova, with decline rates by two or three magnitudes of 7.6 and 14.6 days respectively. The light curve exhibited oscillations during the transition stage. The nova achieved an absolute magnitude at maximum in the range –8.5… –9.1. The distance is in the range 2.6… 3.6 kpc. V2467 Cyg showed an early appearance of forbidden lines during the transition stage. Its evolution is similar to the behavior of V1494 Aql (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Turbulent stresses as a function of shear rate in a local disk model
Authors: Liljeström A.J. , Korpi M.J. , Käpylä P.J. , Brandenburg A. , Lyra W.
Published: January 2009

We present local numerical models of accretion disk turbulence driven by the magnetorotational instability with varying shear rate. The resulting turbulent stresses are compared with predictions of a closure model in which triple correlations are modelled in terms of quadratic correlations. This local model uses five nondimensional parameters to describe the properties of the flow. We attempt to determine these closure parameters for our simulations and find that the model does produce qualitatively correct behaviour. In addition, we present results concerning the shear rate dependency of the magnetic to kinetic energy ratio. We find both the turbulent stress ratio and the total stress to be strongly dependent on the shear rate (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Edge‐on disk galaxies in the SDSS DR6: Fractions of bulgeless and other disk galaxies
Authors: Kautsch S.J.
Published: January 2009

The aim of this study is to determine the fractions of different spiral galaxy types, especially bulgeless disks, from a complete and homogeneous sample of 15 127 edge‐on disk galaxies extracted from the sixth data release from the Sloan Digital Sky Survey. The sample is divided in broad morphological classes and sub types consisting of galaxies with bulges, intermediate types and galaxies which appear bulgeless. A small fraction of disky irregulars is also detected. The morphological separation is based on automated classification criteria which resemble the bulge sizes and the flatness of the disks. Each of these broad classes contains about 1/3 of the total sample. Using strict criteria for selecting pure bulgeless galaxies leads to a fraction of 15% of simple disk galaxies. We compare this fraction to other galaxy catalogs and find an excellent agreement of the observed frequency of bulgeless galaxies. Although the fraction of simple disk galaxies in this study does not represent a “cosmic” fraction of bulgeless galaxies, it shows that the relative abundance of pure disks is comparable to other studies and offers a profound value of the frequency of simple disks in the local Universe. This fraction of simple disks emphasizes the challenge for formation and evolution models of disk galaxies since these models are hard pressed to explain the observed frequency of these objects (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stoichiometric analysis of dissolved organic carbon flux into storage and growth in aerobic granules culture
Authors: Li Yong , Liu Yu , Wang Zhi‐Wu
Published: January 2009

This study attempted to address a fundamental question of whether metabolic behaviors of aerobic granules are different from their counterparts, such as activated sludge and biofilms. A series of respirometric experiments were carried out using mature aerobic granules with mean sizes of 0.75–3.4 mm. Results suggested that metabolism of aerobic granules comprised three consecutive phases: (i) conversion of external dissolved organic carbon to a poly‐β‐hydroxybutyrate‐like substance; (ii) growth of aerobic granules on the stored poly‐β‐hydroxybutyrate‐like substance derived from phase I, and (iii) subsequent endogenous metabolism of aerobic granules. The stoichiometric analysis revealed that the conversion yields of external dissolved organic carbon to the poly‐β‐hydroxybutyrate‐like substance, the growth yields of biomass on storage, and the overall growth yields of biomass on external dissolved organic carbon were not significantly correlated to the sizes of aerobic granules, i.e., the metabolism of aerobic granules would be size independent. The conversion coefficients and growth rates of aerobic granules were found to be comparable with those reported in the activated sludge and biofilms cultures, indicating that there would not be significant difference in the metabolisms of aerobic granules over activated sludge and biofilms. This information will be useful for modeling and designing aerobic granular sludge processes.