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Current Zoology 2012年第6期58卷 851-855页

作者： Diego MONTALTI Maricel GRA A GRILLI René E. MARAGLIANO Guillermo CASSINI Cátedra de Ornitología Faeultad de Ciencias Naturales y Museo Paseo del Bosque B 1900FWA-La Plata Argentina CONICET Cerrito 1248 C1010AAZ-Buenos Aires Argentina Jardín Zoológico de La Plata Paseo del Bosque B1900-La Plata Argentina departamento de ciencias Básicas Universidad National de Luján Ruta 5 y Av. Constitución B6700-Luján Buenos Aires Argentina

Monomorphic birds cannot be sexed visually and discriminant functions on the basis of external morphological variations are frequently used. Our objective was to evaluate the reliability of sex classification functions created from structural measurements of Chilean flamingos Phoenicopterus chilensis museum skins for the gender assignment of live birds. Five measurements were used to develop four discriminant functions： culmen, bill height and width, tarsus length and middle toe claw. The functions were tested on a sample of live flamingos from a zoo. The best classification for museum flamingos was given by a function using tarsus length, bill width and middle toe claw （97%）. However, this function did not give the best classification for the zoo-based flamingos （81%） which had the best sex assignment by a function including measurements of tarsus, culmen and bill height and width （85%）. This shows that a function giving good results in the sample from which it originated may not be as good when applied to another group of animals. Our study emphasizes the need for assessing the accuracy of a function by testing it with other methods to ensure its suitability when being applied .

关键词： Morphometrics Discriminant function Sexual dimorphism Sex classification

Esterase Activities and Biochemical Properties of Lactic Acid Bacteria Isolated from Goat＇s Milk Cheese in Argentina

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Journal of Agricultural Science and Technology(B) 2014年第9期4卷 752-760页

作者： Natalia Veronica Taboada Maria Soledad Lopez Alzogaray Maria Claudia Abeijon Mukdsi Roxana Beatriz Medina departamento de ciencias de los Alimentos Faeultad de Agronomia y Agroindustrias Universidad Nacional de Santiago delEstero Av. Belgrano 1912 (S) Santiago del Estero CP 4200 Argentina Centro de Refereneia Para Lactobacilos (CERELA-CONICET) Chacabuco 145 Tucum(m CP 4000 Argentina faeultad de ciencias de la Salud Universidad del Norte Santo de Aquino 9 de Julio 165 Tueumdn CP 4000 Argentina Facultad de Agronomia y Zootecnia Universidad Nacional de Tucumdn Av. Roca 1900 Tucumdn CP 4000 Argentina

Twenty-two lactic acid bacteria （LAB） strains isolated from Argentinean goat dairy products were evaluated for its biochemical properties and esterase activities relevant to flavor development. Streptococcus thermophilus （UNSE314）, Lactobacillus （L.） delbrueckii subsp, bulgaricus （UNSE309）, L. rhamnosus （UNSE308）, L. plantarum （UNSE287, UNSE316, UNSE317） and Pediococcus pentosaceus （UNSE315） strains presented high acidifying activity. All strains tested metabolized citrate and produced diacetyl-acetoin in goat milk. Based on these results, 10 strains with the best performance in diverse technological properties were selected to determine esterolytic activity. In all evaluated strains, esterase specific activity （ESA） was detected on ct-naphthyl （ct-NA） acetate and 13-naphthyl （[3-NA） acetate, propionate, eaprylate and ct-NA butyrate. No activity was detected on [3-NA laurate. The highest values were detected when using a-NA instead of fI-NA derivatives as substrate. In Pediocoecus strains, wide variability in ESA were observed, which were species- and strain-specific. These results allow us to select strains with biochemical properties and esterase activities to design starter and adjunct cultures that contribute to flavor development during cheese ripening, thus preserving the typical organoleptic characteristics of Argentinean goat cheeses.

关键词： Esterase activity Pediococcus autochthonous starter cultures biochemical properties goat's milk cheese.

Structural and Vibrational Study of 2-（Quinolin-8-yloxy）-Acetic Acid based on FT-IR-Raman Spectroscopy and DFT Calculations

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Journal of Chemistry and Chemical Engineering 2011年第8期5卷 747-758页

作者： Gerardo R. Arganaraz Elida Romano Juan Zinczuk Silvia A. Brandan Catedra de Quimica General. Instituto de Quimica Inorganiea. faeultad de Bioquimica Quimica y Farmacia. Universidad Nacional de Tucuman. Ayacucho 471. 4000. San Miguel de Tucuman. Tucumcin. R. Argentina Instituto de Qulmica Rosario （CONICET-UNR） Facultad de Ciencias Bioquimicas y Farmacduticas Suipacha 531 2000 Rosario Santa Fe. R. Argentina

We have prepared the 2-（quinolin-8-yloxy）-acetic acid and characterized it by infrared and Raman spectroscopies in the solid phase. The density Functional Theory （DFT） method, together with the 6-31G^＊ and 6-311＋＋ G^＊＊ basis sets, show that three stable molecules, for the anhydrous and monohydrated compounds were theoretically determined in the gas phase, and that probably the two more stable conformations are present in the solid phase of the monohydrated compound. The harmonic vibrational wavenumbers for the optimized geometries were calculated at B3LYP/6-31G^＊and B3LYP/6-311＋＋G^＊＊ levels. For a complete assignment of all the observed bands in the vibrational spectra the DFT calculations were combined with Pulay＇s scaled quantum mechanical force field （SQMFF） methodology in order to fit the theoretical Wavenumber values to the experimental ones. The characteristics of the electronic delocalization of all structures of both forms were performed by using natural bond orbital （NBO）, while the corresponding topological properties of electronic charge density are analysed by employing Bader＇s atoms in molecules theory （AIM）.

关键词： 2-(Quinolin-8-yloxy)-acetic acid vibrational spectra molecular structure force field DFT calculations

Effect of Temperature on Titanium Dioxide in Polyethylene Teraphthalate Protective Coatings on ECCS Steels

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材料科学与工程（中英文版） 2010年第5期4卷 51-57页

作者： Ernesto Zumelzu Claudio Ortega Femando Rull Instituto de Materiales y Procesos Termomec6nicos Universidad Austral de Chile Casilla 567 Valdivia Chile Escuela de Mecdmica Faeultad de Ciencias de la lngenieria Universidad Austral de Chile Valdivia Chile Dpto. Fisica de la Materia Condensada Universidad de Valladolid Spain

The study analysed the behaviour of titanium dioxide (TiO2) in polyethylene teraphthalate (PET) polymer coatings on ECCS steel plates. This work determined the thermal source affecting rutile distribution in the PET coating: it originated in the manufacturing processes and thermomechanical treatments of the composite, and affected PET adherence on the steel. These results were contrasted with the behaviour of a non-heated coating to determine the conditions under which the rutile exhibits changes on the PET coating. Measurements at cross-section and parallel intervals from the surface to the metal interface were made by FTIR-ATR and Raman vibrational spectroscopy techniques to characterise the rutile distribution in the PET thickness.

关键词：涂层钢板二氧化钛电子对抗聚乙烯防护涂料作战 PET膜温度

Hardness Enhancement and Corrosion Current of Multilayer Coatings Based on Titanium Nitride

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材料科学与工程（中英文A版） 2015年第7期5卷 257-268页

作者： Arturo Talledo Junior Asencios Karin Paucar Alcides Lopez Carsten Benndorf Rolando Nufiez Jan Petersen faeultad de ciencias Universidad Nacional de Ingenieria Av. Tupac Amaru 210 Lima25 Peril departamento Ingenierla Mec6nica Pontificia Universidad Cat6lica del Peril Av Universitaria s/n Lima 32 Peril Fraunhofer IST BienroderWeg 54 E 38108 Braunschweig Germany

In this article we explore the possibilities to obtain hardness enhancement in three different types of multilayer system: TiN/AlN, TiN/NbN and TiN/TaN, produced by bias-dc magnetron sputtering under the same deposition conditions. Multilayer structure and chemical composition were confirmed by GDOES (Glow discharge optical emission spectroscopy). Crystalline structure of component layers was studied by XRD (X-ray diffraction). Microhardness was measured by using a classic Vickers microdurometer and SEM (Scanning electron microscopy), as well as, by nanoindentation. Corrosion current was determined by Tafel extrapolation method.

关键词：腐蚀电流硬度计多层涂层氮化钛辉光放电发射光谱直流磁控溅射 X射线衍射仪硬度测定