Article
Plant Sciences
Fatemeh Sheibani, Mike Bourget, Robert C. C. Morrow, Cary A. A. Mitchell
Summary: Research shows that reducing the vertical distance between LED lamps and crop surfaces can increase the photosynthetic photon utilization efficiency and crop yield. In the energy-efficiency strategy, energy utilization efficiency significantly improved as the separation distance between lamps and cropping surfaces decreased. In the yield-enhancement strategy, higher yields were achieved with the same energy expenditure at closer separation distances.
FRONTIERS IN PLANT SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Vijay Kumar Sharma, Hilmi Volkan Demir
Summary: The COVID-19 pandemic has led to increased interest in ultraviolet (UV) disinfection, especially for air disinfection. With the development of deep-UV LED and CL chip technologies, compact devices are now being used in disinfection systems, showing promising advancement.
Article
Optics
Abdelhakim Zeghoudi, Abdelber Bendaoud, Helima Slimani, Baghdadi Benazza, Houcine Miloudi, Laurent Canale
Summary: LED lamps, known for their environmental friendliness, long life, low power consumption, and high efficiency, have been widely used in lighting systems. However, the AC/DC conversion in LED lamps by rectifier diodes results in harmonic pollution and poor power quality.
Editorial Material
Optics
Jianchen Zi, Hai Bi
Summary: An LED-integrated excitation cube (LEC) has been designed as a solution for the limitations of conventional fluorescence lamps. The LEC has a decentralized structure, high optical power density, and efficient illumination. With optical efficiency 1-2 orders of magnitude higher than mercury lamps, LECs enable high-quality fluorescence imaging from UV to red spectra and can be easily installed on commercial fluorescence microscopes by replacing traditional fluorescence filter cubes. Additionally, a built-in LEC driver allows the identification of LED types in different spectral bands to optimize operating conditions.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Environmental Sciences
Marina Aliste, Isabel Garrido, Gabriel Perez-Lucas, Pilar Flores, Pilar Hellin, Simon Navarro, Jose Fenoll
Summary: The study found that the combined systems ZnO/Na2S2O8 and TiO2/Na2S2O8 showed higher efficiency in treating organic pollutants in irrigation and tap waters. UV-LED was identified as a suitable alternative for addressing the removal of organic pollutants in water.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Computer Science, Information Systems
Mohammed A. Ismeil, Youssef Badry Hassan, Mohammed Orabi, Abdulaziz Alshareef, Hany S. Hussein
Summary: Researchers are working to improve the efficiency and lifetime of LED lighting fixtures by addressing issues such as the repeated flashlight or Purkinje effect caused by electrolytic capacitors. This paper proposes a free-cost method to reduce the size and cost of LED driver components and manage the voltage and current rating of active components, such as power electronic switches.
Article
Instruments & Instrumentation
A. D. McDonald, M. Febbraro, J. Asaadi, C. C. Havener
Summary: This paper introduces the development of a pulsed light source using discharge from an electrode in various noble gases. It can assist in characterizing and testing vacuum-ultraviolet sensitive light detection devices. The source consists of a unique spark driver circuit, a spark chamber for introducing different noble gases, and an optical attenuation cell which can be filled with different gases to attenuate the pulsed light to single photon levels. The construction, calibration, and characterization of this device deployed at a dedicated light detection test stand at Oak Ridge National Laboratory are described.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Horticulture
John D. Stamford, Jim Stevens, Philip M. Mullineaux, Tracy Lawson
Summary: Determining the optimal light spectrum for crop growth can be challenging and varies depending on the crop species and variety. LED lighting allows for greater control over the light spectrum. This article discusses the roles of different spectral regions and their effects on plant growth and crop quality. It also explores how LED lighting can be used to manipulate plant growth and increase crop productivity, while considering the costs associated with different light treatments.
Article
Thermodynamics
Ahlem Ben Halima, Zouhour Araoud, Laurent Canale, Kamel Charrada, Georges Zissis
Summary: With LED lighting systems, 70% of the energy is lost as thermal energy. By converting this waste heat into light using Peltier modules, the efficiency of the system can be increased. This article evaluates the limitations of these solutions by examining the decrease in luminous efficiency of the LED system caused by the thermal effects of adding Peltier modules, compared to the potential gain in electrical power production.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Energy & Fuels
David Katzin, Leo F. M. Marcelis, Simon van Mourik
Summary: This study examines the energy savings potential of transitioning greenhouses from high-pressure sodium (HPS) to LED lighting in high latitude regions. The results show that transitioning to LEDs can lead to a 10-25% reduction in total energy consumption, but may also increase the demand for heating.
Article
Engineering, Multidisciplinary
Horatiu Albu, Dorin Beu, Tania Rus, Raluca Moldovan, Florin Domnita, Silvia Vilcekova
Summary: The presented study conducted a Life Cycle Assessment of a LED suspended luminaire manufactured in Romania using One Click LCA software. The main environmental impact of the LED luminaire was found to be generated by the operational energy use. The manufacturing stage was found to have a significant environmental impact due to the presence of aluminium in the luminaire body, fixing clips, LED module, and LED driver. The study also analyzed a lighting installation composed of the LED suspended luminaire and proposed implementing daylight system control to reduce operational energy use.
ALEXANDRIA ENGINEERING JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Haonan Yu, Jingming Chan, Balaji Devakumar, Xiaoyong Huang
Summary: In this article, a new highly efficient Mn4+ ion-activated Li3La3W2O12 (LLWO) far-red emitting phosphor was synthesized and characterized. The LLWO:Mn4+ phosphors exhibited bright narrowband far-red emission peaking at 719 nm, which matched well with the absorption spectrum of phytochrome PFR. The phosphors could be efficiently excited by both ultraviolet and blue LED chips, and a LED device utilizing the LLWO:1.2%Mn4+ phosphor showed dual emission bands of blue and far-red.
MATERIALS TODAY CHEMISTRY
(2023)
Article
Construction & Building Technology
H. Zhou, R. Ding, J. Qin, Y. Pan, M. Wang
Summary: The study aimed to measure the illuminance uniformity with obstruction and introduced the illuminance attenuation dispersion rate as a parameter. The experimental results showed significant differences in the illuminance attenuation dispersion rate among different products, and the light spot shape deformed in some products.
LIGHTING RESEARCH & TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Patrick Dahlberg, Nils J. Ziegeler, Peter W. Nolte, Stefan Schweizer
Summary: This paper presents a schematic for an excitation source based on infrared LEDs, which is used for measurements and defect localization in active thermography. The excitation source features multiple control modes and good phase and amplitude stability, making it easy to integrate with existing measurement setups.
APPLIED SCIENCES-BASEL
(2022)
Article
Chemistry, Analytical
Milica Petkovic, Dragana Bajovic, Dejan Vukobratovic, Juraj Machaj, Peter Brida, Graeme McCutcheon, Lina Stankovic, Vladimir Stankovic
Summary: This paper proposes energy-efficient solutions for a smart LED lighting system, which aim to minimize energy consumption while meeting illuminance requirements in a typical office space. The solutions include dimming LED lamps, optimizing LED functionality, and reducing daylight intensity through shading windows. By implementing different optimization algorithms, the proposed optimization problems can be solved to achieve minimal energy consumption and user satisfaction.
