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Results for “Energy efficiency”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Energy efficiency – How far can we raise the bar? Revealing the potential of best available technologies
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Accelerating the energy retrofit of commercial buildings using a database of energy efficiency performance
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Design of incentive programs for accelerating penetration of energy-efficient appliances
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Updates to the China Design Standard for Energy Efficiency in public buildings
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Should commercial mortgage lenders care about energy efficiency? Lessons from a pilot study
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Energy efficiency of an intermediate-temperature solid oxide iron–air redox battery
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Characterization of semi-open liquid desiccant cycle energy efficiency in ventilation air treatment
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Assessment of emerging energy-efficiency technologies for the pulp and paper industry: a technical review
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Efficient energy stable numerical schemes for a phase field moving contact line model
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Do energy efficiency standards hurt consumers? Evidence from household appliance sales
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Context and meaningfulness in energy efficiency labeling: Real estate listings
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Performance and energy efficiency of big data applications in cloud environments: A Hadoop case study
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Photoluminescence properties and efficient energy transfer of Ce3+/Eu2+ activated K2Ba7Si16O40 phosphors
Highlights: • K{sub 2}Ba{sub 7}Si{sub 16}O{sub 40}:Ce{sup 3+}/Eu{sup 2+} phosphors have been synthesized by a high temperature solid-state method with CO atmosphere. • The resonance-type energy transfer by dipole-dipole interaction from Ce{sup 3+} to Eu{sup 2+} in K{sub 2}Ba{sub 7}Si{sub 16}O{sub 40} is demonstrated. • The critical distance between Ce{sup 3+} and Eu{sup 2+} ions is calculated to be 25.06 Å. • The thermal activation energy of K{sub 2}Ba{sub 7}Si{sub 16}O{sub 40} is calculated to be 0.26 eV. - Abstract: Ce{sup 3+}/Eu{sup 2+} activated K{sub 2}Ba{sub 7}Si{sub 16}O{sub 40} phosphors have been synthesized via a high-temperature solid-state method with CO atmosphere. Under ultraviolet (UV) light pump, the photoluminescence (PL) spectra of K{sub 2}Ba{sub 7}Si{sub 16}O{sub 40}: Ce{sup 3+} is composed of a broadband from 300 nm to 500 nm ascribed to the spin-allowed 5d–4f transition of Ce{sup 3+} ions. The optimal concentration is 8% for Ce{sup 3+} single doped K{sub 2}Ba{sub 7}Si{sub 16}O{sub 40} due to the ernergy dispersion between Ce{sup 3+} ions and the critical distance between Ce{sup 3+} ions is 15.05 Å. K{sub 2}Ba{sub 7}Si{sub 16}O{sub 40}: Eu{sup 2+} emits a broad green emission peaking at 498 nm. The spectral overlap between the emission of Ce{sup 3+} and the excitation of Eu{sup 2+} suggests the resonance-type energy transfer from Ce{sup 3+} to Eu{sup 2+}, which is further demonstrated by the decay curves of K{sub 2}Ba{sub 7}Si{sub 16}O{sub 40}: 8 mol% Ce{sup 3+}, m Eu{sup 2+}. The critical distance between Ce{sup 3+} and Eu{sup 2+} ions is calculated to be 25.06 Å by Dexter’s theory. Furthermore, the energy transfer mechanism is dipole-dipole interaction. In addition, the thermal activation energy is calculated to be 0.26 eV. The CIE coordinates can be tuned from blue to green by increasing Eu{sup 2+} ions. All results suggest that K{sub 2}Ba{sub 7}Si{sub 16}O{sub 40}: Ce{sup 3+}, Eu{sup 2+} is potentially useful for near-UV pumped white LEDs.