Concept

Lampe à incandescence halogène

Publications associées (35)

III-N blue-emitting epi-structures with high densities of dislocations: Fundamental mechanisms for efficiency improvement and applications

Since the dawn of humanity, human beings seeked to light their surroundings for their well-being, security and development. The efficiency of ancient lighting devices, e.g. oil lamps or candles, was in the order of 0.03-0.04% and jumped to 0.4-0.6% with th ...

EPFL2024

Printed ecoresorbable temperature sensors for environmental monitoring

Danick Briand, Nicolas Francis Fumeaux, James Alec Pierce Bourely, Melissa Kossairi

Abstract Electronic waste has become a pressing issue, necessitating sustainable solutions for the disposal of electronic devices. While the development of environmentally degradable electronics has gained attention, the fabrication of stable and performan ...

2023

Photonic nanostructures mimicking floral epidermis for perovskite solar cells

Mohammad Khaja Nazeeruddin, Hobeom Kim

Here, we report photonic nanostructures replicated from the adaxial epidermis of flower petals onto light-polymerized coatings using low-cost nanoimprint lithography at ambient temperature. These multifunctional nanocoatings are applied to confer enhanced ...

ELSEVIER2022

Healing plasma current ramp-up by nitrogen seeding in the full tungsten environment of WEST

Olivier Sauter, Federico Alberto Alfredo Felici, Simon Van Mulders

Achieving a successful plasma current ramp-up in a full tungsten tokamak can be challenging due to the large core radiation (and resulting low core temperature) that can be faced with this heavy metallic impurity if its relative concentration is too high. ...

IOP Publishing Ltd2022

Exploiting end-of-life lamps fluorescent powder e-waste as a secondary resource for critical rare earth metals

Christian Ludwig, Rudolf Paul Wilhelm Jozef Struis, Ajay Bhagwan Patil, Mohamed Tarik

The consensus is growing for the UN sustainable development goals regarding responsible consumption, production, and climate actions. Because of growth towards a digital society (“industry 4.0 revolution”), it is needed to have our resources and economies ...

2021

Does glazing color influence our perception of discomfort glare from daylight?

Sneha Jain

Spectrum and correlated colour temperature of light are shown to influence human visual comfort. Previous research conducted with electric light, mainly in the context of vehicular headlamps, have demonstrated that coloured LEDs induce more discomfort glar ...

2021

Elucidating the role of the InGaN UL in the efficiency of InGaN based light-emitting diodes

Camille Haller

Blue III-nitride light-emitting diodes (LEDs) are widely used nowadays in solid-state lighting, as white light can be produced by combining yellow phosphors and blue LEDs. This technology has the advantage to have a higher luminous efficiency than incandes ...

EPFL2019

Lead Halide Residue as a Source of Light-Induced Reversible Defects in Hybrid Perovskite Layers and Solar Cells

Quentin Thomas Jeangros, Jakub Holovsky, Chien-Jen Yang, Martin Ledinsky

Advanced characterization methods avoiding transient effects in combination with solar cell performance monitoring reveal details of reversible light-induced perovskite degradation under vacuum. A clear signature of related deep defects in at least the 1 p ...

2019

Application of the VUV and the soft x-ray systems on JET for the study of intrinsic impurity behavior in neon seeded hybrid discharges

Jonathan Graves

This paper reports on impurity behavior in a set of hybrid discharges with Ne seeding-one of the techniques considered to reduce the power load on reactor walls. A series of experiments carried out with light gas injection on JET with the ITER-Like-Wall (I ...

2018

Ion cyclotron resonance heating for tungsten control in various JET H-mode scenarios

Jonathan Graves, Javier García Hernández

Ion cyclotron resonance heating (ICRH) in the hydrogen minority scheme provides central ion heating and acts favorably on the core tungsten transport. Full wave modeling shows that, at medium power level (4MW), after collisional redistribution, the ratio o ...

2017

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