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101.
Alberto Ortega Rodrigo Escobar Sergio Colle Samuel Luna de Abreu 《Renewable Energy》2010,35(11):2514-2524
The Chilean government has determined that a renewable energy quota of up to 10% of the electrical energy generated must be met by 2024. This plan has already sparked interest in wind, geothermal, hydro and biomass power plants in order to introduce renewable energy systems to the country. Solar energy is being considered only for demonstration, small-scale CSP plants and for domestic water heating applications. This apparent lack of interest in solar energy is partly due to the absence of a valid solar energy database, adequate for energy system simulation and planning activities. One of the available solar radiation databases is 20–40 years old, with measurements taken by pyranographs and Campbell–Stokes devices. A second database from the Chilean Meteorological Service is composed by pyranometer readings, sparsely distributed along the country and available from 1988, with a number of these stations operating intermittently. The Chilean government through its National Energy Commission (CNE) has contracted the formulation of a simulation model and also the deployment of network of measurement stations in northern Chile. Recent efforts by the authors have resulted in a preliminary assessment by satellite image processing. Here, we compare the existing databases of solar radiation in Chile. Monthly mean solar energy maps are created from ground measurements and satellite estimations and compared. It is found that significant deviation exists between sources, and that all ground-station measurements display unknown uncertainty levels, thus highlighting the need for a proper, country-wide long-term resource assessment initiative. However, the solar energy levels throughout the country can be considered as high, and it is thought that they are adequate for energy planning activities – although not yet for proper power plant design and dimensioning. 相似文献
102.
Rodrigo V. Cardoso 《Planning Theory & Practice》2013,14(4):622-624
103.
Immobilization of lipase B from Candida antarctica on epoxy‐functionalized silica: characterization and improving biocatalytic parameters 下载免费PDF全文
104.
Luiz F.G. Setz Isabel Santacruz M. Teresa Colomer Sonia R.H. Mello-Castanho Rodrigo Moreno 《Journal of the European Ceramic Society》2010,30(14):2897-2903
Lanthanum chromite (LaCrO3) is currently the most widely studied material as interconnector layers for solid oxide fuel cells (SOFC). The complexity of microstructures and geometries of SOFC devices, which are usually built-up by lamination of the different constitutive layers, make it necessary a precise control of processing parameters to achieve the desired combination of properties. Much effort has been devoted to the processing of electrodes and electrolytes but the other layers, such as that of interconnecting material, have received scarce attention. This work deals with the preparation and optimisation of the rheological behaviour of concentrated suspensions of Sr- and Co-doped LaCrO3 and the subsequent tape casting to produce homogeneous thin sheets to be used in the SOFC stack.The starting powder was produced by combustion synthesis from the corresponding nitrates and urea as a fuel, and had a final composition of La0.80Sr0.20Cr0.92Co0.08O3. These powders were dispersed in ethanol with commercial copolymers (Hypermer, KD6) to solids loading of up to 58 wt%. The binding system (BS) consisted of a mixture of a binder, polyvinyl butyral-co-vinyl alcohol-co-vinyl acetate (PVA-PVAc), and two plasticizers, polyethyleneglycol (PEG400) and benzylbutylphthalate (BBP). The effect of the binding system content and the binder-to-plasticizer ratio on the tape casting performance and the characteristics of the green and the sintered tapes, were studied, as well as the influence of the casting parameters (casting speed and blades height). 相似文献
105.
Aline G. Cunha Angelo A. T. da Silva Mateus G. Godoy Rodrigo V. Almeida Alessandro B. C. Simas Denise M. G. Freire 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2013,88(2):205-211
BACKGROUND: The response surface methodology was successfully applied to the optimization of the reaction variables for the kinetic resolution of a precursor of high‐value myo‐inositols, ( ± )‐1,2‐O‐isopropylidene‐3,6‐di‐O‐benzyl‐myo‐inositol (( ± )‐1), by Novozym 435. The resolutions were run separately, with two acylating agents, ethyl acetate and vinyl acetate, in a solvent‐free system. The variables analyzed were reaction temperature, substrate concentration, water concentration and enzyme activity. A statistical model was employed for the evaluation of the influence of the variables on conversion and enantiomeric excess (ee). RESULTS: The optimal conditions for this resolution using vinyl acetate as acylating agent were 45 °C, 5 mg mL?1 of substrate, 71 U of enzyme activity and 0%w/w of water concentration. The high conversion (49.2 %) and ee (>99%) reached in the chemoenzymatic synthesis of acylated product, L‐(?)‐5‐O‐Acetyl‐3,6‐di‐O‐benzyl‐1,2‐O‐isopropylidene‐myo‐inositol, secure the efficient synthesis of the D enantiomorph present in the original racemic mixture (( ± )‐1) as well. CONCLUSIONS: The use of the experimental design strategy was productive, leading to a 14‐fold increase in the productivity of the reaction compared with the non‐optimized conditions. Both derivative L‐(?)‐2 and remaining substrate D‐(+)‐1 were obtained at high ee. © 2012 Society of Chemical Industry 相似文献
106.
Multi-View Scene Capture by Surfel Sampling: From Video Streams to Non-Rigid 3D Motion,Shape and Reflectance 总被引:1,自引:0,他引:1
Carceroni Rodrigo L. Kutulakos Kiriakos N. 《International Journal of Computer Vision》2002,49(2-3):175-214
In this paper we study the problem of recovering the 3D shape, reflectance, and non-rigid motion properties of a dynamic 3D scene. Because these properties are completely unknown and because the scene's shape and motion may be non-smooth, our approach uses multiple views to build a piecewise-continuous geometric and radiometric representation of the scene's trace in space-time. A basic primitive of this representation is the dynamic surfel, which (1) encodes the instantaneous local shape, reflectance, and motion of a small and bounded region in the scene, and (2) enables accurate prediction of the region's dynamic appearance under known illumination conditions. We show that complete surfel-based reconstructions can be created by repeatedly applying an algorithm called Surfel Sampling that combines sampling and parameter estimation to fit a single surfel to a small, bounded region of space-time. Experimental results with the Phong reflectancemodel and complex real scenes (clothing, shiny objects, skin) illustrate our method's ability to explain pixels and pixel variations in terms of their underlying causes—shape, reflectance, motion, illumination, and visibility. 相似文献
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109.
Rodrigo Scherer Paula Rossini Augusti Vivian Caetano Bochi Camila Steffens Leadir Lucy Martins Fries Ana Paula Daniel Ernesto Hashime Kubota João Radünz Neto Tatiana Emanuelli 《Food chemistry》2006,99(1):136-142
The effect of two slaughter methods (immersion in ice-water slurry and electrical stunning followed by ice slurry asphyxiation) on chemical and microbiological parameters of grass carp (Ctenopharyngodon idella) stored in ice for 20 days was evaluated. No differences in total volatile basic nitrogen (TVB-N), pH, carbohydrate or protein content of mucus were observed between the slaughter methods. Ice-slaughtered fish had lower bacteria counts at the beginning of storage, but higher counts than fish slaughtered by electricity at the end of storage (p < 0.05). However, no significant differences in the shelf life were observed between the slaughter methods evaluated (limit of acceptability – counts > 3 × 106 CFU g−1 – attained after 13–16 days). Results indicated that the chemical parameters evaluated have a limited applicability to assess the shelf life of grass carp stored in ice, since pH limit (6.8) was exceeded after 4 days, while TVB-N limit (30 mg%) was not attained after 20 days of storage. 相似文献
110.