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951.
952.
Luisa D’Amore Rossella Arcucci Luisa Carracciuolo Almerico Murli 《Journal of scientific computing》2014,61(2):239-257
Data assimilation (DA) is a methodology for combining mathematical models simulating complex systems (the background knowledge) and measurements (the reality or observational data) in order to improve the estimate of the system state (the forecast). The DA is an inverse and ill posed problem usually used to handle a huge amount of data, so, it is a large and computationally expensive problem. Here we focus on scalable methods that makes DA applications feasible for a huge number of background data and observations. We present a scalable algorithm for solving variational DA which is highly parallel. We provide a mathematical formalization of this approach and we also study the performance of the resulted algorithm. 相似文献
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954.
Marina Serantoni Andreana PiancastelliAnna Luisa Costa Laura Esposito 《Optical Materials》2012,34(6):995-1001
Spray drying parameters have been optimized for the preparation of granulated stoichiometric mixture of oxides. These oxides are used in the production of Yb:YAG laser grade ceramic materials by reactive sintering. The selected compositions were Yb0.294Y2.706Al5O12 and Yb0.03Y2.97Al5O12, i.e. YAG doped with 9.8 and 1.0 at% of Yb with respect to the overall Y + Yb amount. The influence of solid content, drying medium flux, temperature and aspiration rate of the spray drying process on the transparency of the sintered materials has been evaluated. Sintering was conducted under high vacuum and clean atmosphere in the temperature range of 1650-1735 °C and with a soaking time of 16 h. SEM analysis of the microstructure of granulated powders and sintered materials, as well as the transmittance measurement, were used as tools to guide the selection of the best spray drying parameters. 相似文献
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Mírian Luisa Faria Freitas Tiago Carregari Polachini Ana Cristina de Souza Javier Telis‐Romero 《International Journal of Food Science & Technology》2016,51(1):250-259
This study focuses on isotherms, isosteric heat of sorption and enthalpy–entropy mechanism of water sorption of grated Parmesan cheese at simulating conditions of storage and drying processes. Isotherms were determined by gravimetric method using different saturated salt solutions. Samples were submitted to different temperatures, and several models were used to fit experimental data, GAB and modified GAB being those which best represented experimental data in all temperature ranges. The isosteric heat of sorption was calculated by Clausius–Clapeyron equation, and higher values of integral isosteric sorption heat were verified for storage temperatures. Besides it, both conditions showed higher values of sorption heat corresponding to low water content. This phenomenon was supported by the enthalpy–entropy compensation study, which demonstrated a higher spontaneity of water sorption for storage temperatures, confirming that the lower the water content of food products is, the stronger the intermolecular bonds of water are. 相似文献
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In this study, an inorganic mixture based on bischofite (industrial by‐product) was developed and characterized for its application as a phase change material for low‐temperature thermal energy storage. The most appropriate composition was established as 40 wt% bischofite and 60 wt% Mg(NO3)2 · 6H2O. Thermophysical properties were defined and compared with those of the mixture with synthetic MgCl2 · 6H2O. The heat of fusion and melting temperature were measured as 62.0°C and 132.5 kJ kg?1 for the mixture with MgCl2 · 6H2O and 58.2°C and 116.9 kJ kg?1 for the mixture with bischofite. The specific heat capacity values, cycling, and thermal stability for both mixtures were also determined. For the mixture with MgCl2 · 6H2O, the densities of the solid and liquid states were 1517 kg m?3 (ambient temperature) and 1515 kg m?3 (at 60‐70°C), respectively. For the mixture with bischofite, the densities of the solid and liquid states were 1525 kg m?3 (ambient temperature) and 1535 kg m?3 (at 60‐70°C), respectively. Both mixtures show supercooling of about 23.4 and 34.1°C for the mixture with bischofite and MgCl2 · 6H2O, respectively. In addition, it was shown that supercooling may be reduced by increasing the quantity of material tested. Thereby, it was established that an inorganic mixture based on bischofite is a promising PCM for low‐temperature thermal energy storage applications. 相似文献
960.
Development of Lemon Marmalade Formulated with New Sweeteners (Isomaltulose and Tagatose): Effect on Antioxidant,Rheological and Optical Properties
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