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891.
Brandy de Jerez plays a very important role in the economy of its production area. Currently, there are many wineries interested in innovating and diversifying their products, demanding a method which would allow them to age the spirits in a quick and simple way, enabling the testing of different variables in its elaboration. 相似文献
892.
Sergio Nogales‐Delgado María del Carmen Fuentes‐Pérez Concepción Ayuso‐Yuste Diego Bohoyo‐Gil 《International Journal of Food Science & Technology》2014,49(1):114-120
Nectarine [Prunus persica (L.) Batsch] is a sought‐after fruit due to its properties. In addition, minimally processed produces are more and more accepted by consumers. Four nectarine cultivars (‘Early Top’, ‘Nectaprima’, ‘Big Top’ and ‘Venus’) were selected to study their suitability for minimal processing. Samples were processed in a clean room at 8 °C, washed them in water (4 °C) and stored at 4 °C in modified atmosphere packaging. The samples were analysed at 0, 3, 6 and 9 days of storage, and quality parameters as well as functional compounds (polyphenols and polyphenol oxidase activity) were studied. Principal component analysis (PCA) was carried out to assess the relationship between nectarine cultivars and determined parameters. In conclusion, ‘Early Top’ and ‘Nectaprima’ cultivars showed the best quality results and therefore a promising suitability for fresh‐cut processing. Nevertheless, the remaining cultivars should not be ruled out due to their functional content, advising additional conservation treatments for them. 相似文献
893.
894.
Daniel Avram Codruta Rotaru Bogdan Cojocaru Margarita Sanchez-Dominiguez Mihaela Florea Carmen Tiseanu 《Journal of Materials Science》2014,49(5):2117-2126
We report on the homogeneity, structural and luminescence properties of ceria nanoparticles doped with Eu3+. Eu3+ in concentration of 1, 5 and 10 wt% was incorporated via wetness impregnation into preformed ceria nanoparticles followed by calcination in air at 1000 °C. A remarkable homogeneity of Eu3+-ceria solid solutions is measured for ceria grown by citrate and micro-emulsion methods using Raman, Diffuse Reflectance in UV–Vis, photoluminescence spectroscopies and X-ray diffraction, even for the Eu3+ concentration of 10 wt%. The emission properties of all Eu3+-doped ceria samples are well-characterized by a two main centre model assigned to perturbed and isolated Eu3+ centres. These centres correspond to Eu3+ located in the nearest (local symmetry lower than cubic and Eu3+-oxygen coordination lower than eight) and next-nearest-neighbour positions (cubic local symmetry and eightfold Eu3+-oxygen coordination) to oxygen vacancy, respectively. With increase of Eu3+ concentration, both the oxygen vacancy concentration and the relative contribution of the perturbed Eu3+ centre to the total emission increase. It is established that the characteristic emission and excitation spectra of the two main Eu3+ centres as well as the overall multisite distribution of Eu3+ within ceria lattice are intrinsic properties of Eu3+-doped ceria since these do not depend on synthesis route, nanoparticle size and Eu3+ concentration. 相似文献
895.
Anna C. Venturini José A. F. Faria Ricardo A'. Olinda Carmen J. Contreras‐Castillo 《Packaging Technology and Science》2014,27(1):29-35
Beef steaks from Gluteus medius, Longissimus dorsi, Psoas major and ground beef from Triceps brachii were packed in master packages containing expanded polystyrene trays overwrapped with polyvinyl chloride film under an anoxic atmosphere containing 0.2% CO, 60.0% CO2 and 39.8% N2 (T1) or 0.2% CO/99.8% CO2 plus oxygen scavengers. After 28 days of storage at 1 and 4°C, the meat quality was evaluated. The visual and instrumental colour of the beef steaks and ground beef were similar to that of fresh meat. Pathogenic bacteria were not detected, and psychrotrophic bacterial counts were lower than 7.5 log CFU/g. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
896.
Beatriz Galiana Bodgan Oprea Yves Huttel Carmen Ballesteros 《Journal of Materials Science: Materials in Electronics》2014,25(2):659-663
The crystallization and structure of Fe–B nanoparticles (NPs) of different sizes formed in a single process by gas aggregation from Fe80B20 targets were analyzed by transmission electron microscopy. It is concluded that all NPs are covered by an amorphous Fe–B shell while the crystal structure of the NPs core depends on their size. Large NPs with diameters ≥30 nm are monocrystalline tetragonal Fe3B, small diameter NPs (≤20 nm) are completely amorphous whereas in middle size NPs, with diameters between 20 and 30 nm, difference Fe–B phases (tetragonal Fe3B and orthorhombic FeB) together with defaulted areas are observed. This work opens new possibilities to produce Fe–B NPs tailoring their magnetic properties by controlling their size and composition. 相似文献
897.
898.
Thermodynamic and kinetic study on ammonium removal from a synthetic water solution using ion exchange resin 总被引:1,自引:0,他引:1
Mihaela Sica Anca Duta Carmen Teodosiu Camelia Draghici 《Clean Technologies and Environmental Policy》2014,16(2):351-359
Ammonium removal from the wastewater treatment effluents is mandatory considering the imposed discharge limits and the recycling/reuse requirements. Ion exchange represents a viable alternative for the biological processes of ammonium removal, although concurrent processes make modeling complex. This study reports on the performance of a commercial cation exchange resin, PUROLITE C150H, for ammonium removal from synthetic aqueous solutions. Thermodynamic and kinetic process parameters are calculated using the Langmuir model (thermodynamic study) and the shrinking core model (kinetic study); the data are correlated with the surface properties of the substrate, outlining the adsorption mechanism. For initial ammonium concentrations of 25–150 mg NH4 +/L, removal efficiencies of 80–90 % were obtained. 相似文献
899.
Fabio Bellavia Antonino Cacioppo Carmen Alina Lupaşcu Pietro Messina Giuseppe Scardina Domenico Tegolo Cesare Valenti 《Computer methods and programs in biomedicine》2014
We aim to describe a new non-parametric methodology to support the clinician during the diagnostic process of oral videocapillaroscopy to evaluate peripheral microcirculation. Our methodology, mainly based on wavelet analysis and mathematical morphology to preprocess the images, segments them by minimizing the within-class luminosity variance of both capillaries and background. Experiments were carried out on a set of real microphotographs to validate this approach versus handmade segmentations provided by physicians. By using a leave-one-patient-out approach, we pointed out that our methodology is robust, according to precision–recall criteria (average precision and recall are equal to 0.924 and 0.923, respectively) and it acts as a physician in terms of the Jaccard index (mean and standard deviation equal to 0.858 and 0.064, respectively). 相似文献
900.
Printable,Transparent, and Flexible Touch Panels Working in Sunlight and Moist Environments 下载免费PDF全文
Tiina Vuorinen Mari Zakrzewski Satu Rajala Donald Lupo Jukka Vanhala Karri Palovuori Sampo Tuukkanen 《Advanced functional materials》2014,24(40):6340-6347
The ongoing revolution of touch‐based user interfaces sets new requirements for touch panel technologies, including the need to operate in a wide range of environments. Such touch panels need to endure moisture and sunlight. Moreover, they often need to be curved or flexible. Thus, there is a need for new technologies suitable, for example, for home appliances used in the kitchen or the bathroom, automotive applications, and e‐paper. In this work, the development of transparent and flexible touch panels for moist environments is reported. A piezoelectric polymer, poly(vinylidene difluoride) (PVDF), is used as a functional substrate material. Transparent electrodes are fabricated on both sides of a PVDF film using a graphene‐based ink and spray coating. The excellent performance of the touch panels is demonstrated in moist and underwater conditions. Also, the transparent device shows very small pyroelectric response to radiative heating in comparison to a non‐transparent device. Solution processable electrode materials in combination with functional substrates allow the low‐cost and high‐throughput manufacturing of touch panels using printing technologies. 相似文献