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43.
Carolina Pereira Kechinski Cândida Raquel Scherrer Montero Pâmela Virgínia Ramos Guimarães Caciano Pelajo Zapata Noreña Lígia Damasceno Ferreira Marczak Isabel Cristina Tessaro Renar João Bender 《Food and Bioproducts Processing》2012,90(2):118-122
This study examined the effects of O3 and hot water treatments on the epidermis of Golden papaya fruit. Heat treatments were applied in a hot water brushing (HWB) system. Papayas were brushed under a pressurized hot water rinse stage at 45, 55 and 65 °C for 60 s. In the HWB treatment, 4 ppm ozone was applied to the papayas for 1 or 2 min. The results show that ozone applications did not affect the fruit's cuticular surface, while heat treatments allowed natural fissures on the fruit epidermis to recover. Several crystalloid forms were identified on the epidermis of the papayas after the heat treatments. The predominant crystalloid forms on papayas are tubular and there is a positive response to temperature; the higher the temperature, the larger and more frequent the tubular crystalloids. 相似文献
44.
Manuel Portugal Ferreira Cláudia Frias Pinto Fernando Ribeiro Serra 《Scientometrics》2014,98(3):1899-1922
Transaction costs theory (TCT) has long been an important conceptual lens for examining International Business (IB) phenomena and perhaps especially relevant for the study of multinational corporations, entry mode choices and location selection. In this paper we examine the extent to which TCT been used and has impacted IB research. Methodologically, we conduct a bibliometric study of the articles published on nine top journals for publishing IB-related research. We use Jean-François Hennart’s research as the key marker for TCT in IB research given that Hennart’s work has been a hallmark in the discipline. On a sample of 377 articles published between 1982 and 2010, and using the works rather than the authors as the unit of analysis, we analyze citations, co-citations and a spatial visualization of the intellectual research themes delved into. Our analyses provide insights on the influence of Hennart but more broadly of TCT on IB research over the past three decades. We conclude that the TCT has a pervasive influence on a large array of IB research and that Hennart’s work is boundary-spanning, connecting several research themes. 相似文献
45.
Alok K. Jha Neeraj Khare R. Pinto 《Journal of Superconductivity and Novel Magnetism》2012,25(2):377-380
Thin films of YBCO and YBCO:BaZrO3 (BZO) nanocomposite have been deposited using the pulsed laser deposition technique. Substantial increase in critical current
density (J
C
) and pinning force density (F
p
) of the nanocomposite thin films was observed. The possible pinning mechanism in YBCO:BZO nanocomposite thin films has been
explored and compared with the pinning mechanism in pure YBCO thin film by studying the variation of J
C
with magnetic field (B) and temperature. In the intermediate field regime (0.1–1 T), J
C
follows B
−α
with nearly similar values of α for YBCO and YBCO:BZO nanocomposite thin films indicating similar pinning mechanism in both thin films. The variation of
J
C
with reduced temperature (t=T/T
C
) has been studied for both the films and it was observed that the mechanism of pinning in both YBCO and YBCO:BZO thin films
is similar (δT
C
pinning). The observed enhanced values of J
C
and F
p
of the nanocomposite thin film is attributed to the presence of BZO nanoparticles, which induces more defects due to lattice
mismatch between YBCO and BZO leading to improved flux pinning properties of the nanocomposite thin film. 相似文献
46.
This paper extends the emerging literature on the value of trademarks for innovation studies and policy-making with the first empirical study at the trademark level. It gives a view on how companies use trademarks and interpret trademark activities. A sample of 660 new Benelux trademarks registered by small- and medium-sized enterprises reveals that 60 per cent of recently registered Benelux trademarks refer to innovation activity, predominantly to product or service innovation. The reference to innovation co-varies with various applicant and trademark characteristics unknown from previous studies. Finally, the sample reveals that most of the trademarks used to signal innovative offers are filed close to its market introduction without combining them with other intellectual property rights. This holds especially for trademarks related to service innovation. 相似文献
47.
María Carolina Martín Vilma Inés Morata de Ambrosini 《International Journal of Food Science & Technology》2014,49(8):1893-1901
The effect of a new cold‐active pectinolytic system on colour of Malbec wines was studied under the following winemaking conditions: (i) fermentation at low temperature (20 °C) and (ii) prefermentative cold maceration (PCM) (5 °C–7 days) followed by traditional fermentation (28 °C). The pectinolytic system was mainly composed of polymethylgalacturonase and pectin lyase activities, detected under similar conditions to those in winemaking (pH 3.6–20 °C). The results show that the enzyme system significantly accelerated colour extraction by reducing the maceration time necessary for vinification at low temperature and shortening the PCM stage. Enzyme‐treated wines exhibited better chromatic parameters than their controls at devatting and after 6 months of storage. The cold‐active enzyme compensated the decrease in colour extraction due to the low maceration temperature, achieving high‐quality wines with chromatic characteristics similar to those of traditional wines. 相似文献
48.
Aída R. Callejas-Cárdenas Irma Caro Carolina Blanco Luz H. Villalobos-Delgado Nuria Prieto Raúl Bodas Francisco J. Giráldez Javier Mateo 《Meat science》2014
The effects of vacuum ageing on the quality changes of lamb steaks during retail display were assessed. Biceps femoris and Quadriceps femoris muscles from thirty early fattening lambs fed barley straw and concentrate or alfalfa and concentrate were used. Half of the muscles were vacuum aged for three weeks (VA), and the other half were not aged (control). Control and VA muscles were sliced and aerobically displayed. Weight loss, pH, aldehyde contents, instrumental color characteristics and color acceptance were measured at display days 1, 3, 7 and 14. At day 1 redness was higher in VA lamb. However, redness of VA lamb decreases more rapidly during further storage. Redness and color acceptance decreased in VA lamb from day 3, whereas in not-aged lamb the decrease was observed from day 7 onwards. From days 7 to 14 a drop of color acceptance accompanied by an increase in pH and a decrease in lightness was observed in control and VA lamb. 相似文献
49.
Valéria T. Crexi Micheli L. Monte Maurício L. Monte Luiz A. A. Pinto 《Journal of the American Oil Chemists' Society》2012,89(2):329-334
The aims of this study were to compare three treatments in the chemical hydrolysis reaction of bleached oil from carp (Cyprinus carpio) heads and to obtain polyunsaturated fatty acid concentrates by urea complexation. The three treatments were carried out
with different oil:ethanol molar ratios. In the treatment with a 1:39 molar ratio, a higher yield of free fatty acids was
found. These fatty acids were submitted to urea complexation (−10 °C for 20 h, and urea–fatty acid ratio of 4.5–1). There
was a 31.4% increase in monounsaturated and polyunsaturated fatty acids (MUFA and PUFA) content and a 75% decrease in saturated
fatty acids (SAF) content. An increase of 85.4% in the EPA + DHA content was found. The non-urea complexing fraction can be
considered a rich source of MUFA and PUFA with a total amount of 88.9%. 相似文献
50.
L. S. Ribeiro T. Pinto A. Monteiro O. S. G. P. Soares C. Pereira C. Freire M. F. R. Pereira 《Journal of Materials Science》2013,48(14):5085-5092
The aim of this work was the fabrication of mesoporous silica nanoparticles functionalized with thermochromic dye for further incorporation onto textiles. The nanosilicas were prepared under alkaline conditions in the presence of the surfactant hexadecyltrimethylammonium chloride and functionalized with the organosilane dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (C18-NTMS). The dye was incorporated onto the mesoporous silica nanoparticles by two different methods: co-condensation and post-grafting, i.e. by adding the dye during or after the synthesis of the nanosilica, respectively. The morphology, particle and pore size, chemical composition, and textural properties of the silica nanoparticles were characterized by scanning electron microscopy (SEM), dynamic light scattering, N2 adsorption isotherms at ?196 °C, Fourier transform infrared spectroscopy and thermogravimetry. The silica nanoparticles prepared with and without dye presented spherical shape (by SEM) and particle size ranging from 15 to 40 nm. The infrared spectra revealed the characteristic bands of silica and organosilane (in the cases where it was used). The prepared materials presented colour change when submitted to different conditions. The thermochromic dye-functionalized nanosilicas were efficiently immobilized into cotton fabric and tests were performed to verify the washing fastness. After washing, a slight decrease on the amount of silica was noticed, but much of it remained on the textile. The functionalized textiles presented a colour change within different conditions. 相似文献