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Bauxite and silica particles are candidate materials for solar thermal energy storage at high temperatures. The temperature-dependent emittance of packed beds with bauxite and silica particles was measured using a newly upgraded emissometer at wavelengths 2 ÎŒm †λ †16 ÎŒm and temperatures up to ~730 K. The room-temperature emittance was obtained from the measured directional-hemispherical reflectance. A fused silica disc was used to test the emissometer by comparing the measured spectral emittance with the calculated emittance from a fitted Lorentz oscillator model. For the polycrystalline silica particles and the fused silica disc, the measured emittance increases with temperature in the mid-infrared region. The underlying mechanism is interpreted as the temperature-dependent damping coefficient in the Lorentz oscillator model. Two types of bauxite particles with different compositions and sizes were investigated. For λ > 10 ÎŒm, the measured emittance at elevated temperatures is higher than that at room temperature. In the region 2 ÎŒm < λ < 6 ÎŒm, the temperature dependence varies for different types of particles. The total emittance of bauxite particle beds was calculated by spectral integration using Planckâs distribution at the prescribed temperature. The calculated total emittance is between 0.89 and 0.96, but it does not change monotonically with temperature.
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ABALONEđđ Photosensors for the IceCube experiment
The ABALONETM Photosensor Technology (U.S. Pat. 9,064,678) is a modern, scalable technology specifically invented for cost-effective mass production, robustness, and high performance. We present the performance of advanced fused-silica ABALONE Photosensors, developed specifically for the potential extension of the IceCube neutrino experiment, and stresstested for 120 days. The resulting performance makes a significant difference: intrinsic gain in the high 10 8 range, total afterpulsing rate of only 5x10-3 ions per photoelectron, sub-nanosecond timing resolution, single-photon sensitivity, and unique radio-purity and UV sensitivity, thanks to the fused silica componentsâat no additional cost to the assembly process.
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- Award ID(s):
- 1927067
- PAR ID:
- 10320041
- Date Published:
- Journal Name:
- Nuclear instruments and methods in physics research
- ISSN:
- 1872-9606
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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