Vibration behavior of CSP assemblies with and without underfill
This paper presents vibration behavior of these assemblies along with optical and SEM cross-sectional micrographs taken after failures.
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This paper presents vibration behavior of these assemblies along with optical and SEM cross-sectional micrographs taken after failures.
Near-blackbody enclosed particle receiver can support high-temperature thermal energy storage and high-efficiency power cycles.
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This study examines the differences in direct normal irradiance (DNI) in the two versions of the National Solar Radiation Database (NSRDB) produced by the National Renewable Energy Laboratory. Version 3 of the NSRDB includes significant changes in various parts of the radiative transfer model and inputs to the model from Version 2. The changes in Version 3 resulted in less uncertainty than Version 2. The study quantified the uncertainty and the spatial and temporal variability under clear-sky conditions. The uncertainty estimation was performed using a standardized method, A Guide to the Expression of Uncertainty in Measurement (GUM). The method includes high-quality ground-measured data for seven of the National Oceanic and Atmospheric Administration's Surface Radiation Budget Network (SURFRAD) stations for 1998-2015.
A ternary molten chloride has been suggested as a high temperature (550-720 °C) sensible heat storage medium for a two-tank system. An effective thermal insulation is proposed to provide an opportunity for the fabrication of both the hot and cold storage tanks from lower cost metals, e.g. A240-347H, by maintaining the tank wall below 500 °C. To achieve this, the hot storage tank mainly comprises of inner shell (11.4 cm of a refractory brick as liner (KX-99 ®), 30 cm of insulation brick) and outer metal shell, where 5 cm of frozen layer of PCM800 (NaCl), and 5 cm of ceramic wool fill the annular space between the shells. Another layer of ceramic wool was introduced at the outer side of the metal shell to keep the temperature lower than 60 °C. ANSYS Fluent was used for the numerical study of the cool down behavior of the system during idle period when tank is quarter-filled. The heat transfer modes were considered as radiation and natural convection heat transfer from the hot molten salt at 720 °C, conduction through the solid layers and convection heat transfer from the outer shell to the environment at 15 °C. The results showed that the proposed insulation system including a frozen layer of PCM800 maintains the temperature at the metal wall lower than 500 °C, and lower than 60 °C at the outer side of the tank. Apart from the insulation property of the frozen layer of PCM800, it absorbs any leak of hot molten salt, acting as a barrier between salt and the metal shell. The thermal performance analysis provide an insight into the benefits of the multilayer insulation.
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The contribution of each component of a power generation plant to the levelized cost of energy (LCOE) can be estimated and used to increase the power output while reducing system operation and maintenance costs. The LCOE is used in order to quantify solar receiver coating influence on the LCOE of solar power towers. Two new parameters are introduced: the absolute levelized cost of coating (LCOC) and the LCOC efficiency. Depending on the material properties, aging, costs, and temperature, the absolute LCOC enables quantifying the cost-effectiveness of absorber coatings, as well as finding optimal operating conditions. The absolute LCOC is investigated for different hypothetic coatings and is demonstrated on Pyromark 2500 paint. Results show that absorber coatings yield lower LCOE values in most cases, even at significant costs. Optimal reapplication intervals range from one to five years. At receiver temperatures greater than 700 °C, non-selective coatings are not always worthwhile while durable selective coatings consistently reduce the LCOE—up to 12% of the value obtained for an uncoated receiver. Moreover the absolute LCOC is a powerful tool to characterize and compare different coatings, not only considering their initial efficiencies but also including their durability.
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The soluble molecular selenophosphate salts ACsP(2)Se(8) (A = K, Rb, Cs) crystallize in the orthorhombic space group Ccce with a = 14.982(3) A, b = 24.579(5) A, and c = 13.065(3) A for the Cs salt and a = 14.782(3) A, b = 23.954(5) A, and c = 13.044(3) A for the K analogue. ACsP2Se8 is composed of the molecular 6-membered ring, [P2Se8](2-), in the twist conformation charge balanced by alkali metals. The band gaps of these compounds are 2.44 +/- 0.2 eV for Cs2P2Se8, 2.41 +/- 0.2 eV for RbCsP2Se8, and 2.36 +/- 0.2 eV for KCsP2Se8. The amorphous versions of these materials can be made by water quenching the melt and have band gaps for all ACsP(2)Se(8) of 2.12 +/- 0.2 eV. Raman spectroscopic studies exhibit active modes of PSe4 and Se Se in the compound. Solution P-31 NMR studies shed light into the interesting conformational fluxionality of the [P2Se8](2-) anion, including a conformation that has not been previously observed. Thermal analysis reveals ACsP(2)Se(8) exhibits a phase transition, which we investigate by in situ synchrotron powder X-ray diffraction. Third harmonic generation (THG) nonlinear optical measurements determined the THG coefficient, chi(3), for amorphous and crystalline Cs2P2Se8 of 1.8 +/- 0.2 X 105 pm(2)/V-2 and 2.4 +/- 0.1 X 105 pm2/V2, respectively.
Abstract The multiple stages of the malaria parasite life cycle hampers vaccine development. Combining a pre-erythrocytic antigen with a transmission-blocking antigen would target two independent stages of the life cycle for disease control, resulting in a multistage vaccine that can prevent infection and disease transmission simultaneously. Here, we generated a self-assembled ferritin nanoparticle vaccine that simultaneously presents designed immunogens CSPj5c and 17-4 from the infection-blocking circumsporozoite and the transmission-blocking Pfs48/45 antigens. These immunogens were designed, through structure-based approaches, to retain protective epitopes and confer protection upon vaccination. Immunization with CSPj5c-17-4-ferritin nanoparticles conferred protection against challenge with transgenic sporozoites expressingPlasmodium falciparumCSP in mice, and purified IgGs from immunized rabbits elicited potent transmission-reducing activity. Addition of the engineered 17-4 improved the immune responses to CSPj5c and protection from sporozoite challenge. CSPj5c-17-4-ferritin is therefore a promising multistage malaria vaccine with a potential role in malaria control.