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Ergül, Erman (author), van Weelderen, Erik (author)In this thesis for the Bachelor’s Degree in Electrical Engineering, a Control Unit (PCB and software) is designed for inside the UVC Seed Disinfection Machine of Team UVO. The machine consists of four modules: the Control Unit, the LED Driver, the motor controller and the power supply. The Control Unit allows a user to input the intensity per...bachelor thesis 2023
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Herzog, Alexander (author), Benkner, Simon (author), Zandi, Babak (author), Buffolo, Matteo (author), van Driel, W.D. (author), Meneghini, Matteo (author), Khanh, Tran Quoc (author)We report on the degradation mechanisms and dynamics of silicone encapsulated ultraviolet A (UV-A) high-power light-emitting diodes (LEDs), with a peak wavelength of 365nm. The stress tests were carried out for a period of 8665 hours with forward currents between 350mA and 700mA and junction temperatures up to 132°C. Depending on stress...journal article 2023
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Zhu, Yifan (author), Lu, Huimin (author), Wang, Jianping (author), Yu, Tongjun (author), Li, Z.Z.L. (author), Tian, Yucheng (author)In order to improve the light extraction of AlGaN-based short wavelength ultraviolet light emitting diodes (DUC-LEDs), a type of microstructure with high aspect ratio is introduced and optimized on the AlN substrate surface. And, particle swarm optimization (PSO) algorithm is used to inverse design of the surface microstructure to maximize...journal article 2023
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Wang, C.W. (author), Jiang, W. (author), Yang, K. (author), Sarsenbayeva, Z. (author), Tag, B. (author), Dingler, T. (author), Goncalves, J. (author), Kostakos, V. (author)Objectives: Hand hygiene has long been promoted as the most effective way to prevent the transmission of infection. However, due to low compliance and low quality of hand hygiene reported in previous studies, constant monitoring of hand hygiene compliance and quality among healthcare workers is crucial. This study investigated the feasibility...journal article 2023
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Peña, Álvaro (author), Matatagui, Daniel (author), Ricciardella, F. (author), Sacco, L.N. (author), Vollebregt, S. (author), Otero, Daniel (author), López-Sánchez, Jesús (author), Marín, Pilar (author), Horrillo, Mari Carmen (author)Nitrogen dioxide (NO<sub>2</sub>) is a potential hazard to human health at low concentrations, below one part per million (ppm). NO<sub>2</sub> can be monitored using gas sensors based on multi-layered graphene operating at ambient temperature. However, reliable detection of concentrations on the order of parts per million and lower is...journal article 2023
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Chatterjee, Subham (author), Das, Supriyo Kumar (author), Behera, Pravat Kumar (author), Ghosh, D. (author), Chakraborty, Arindam (author), Patel, Priyank Pravin (author), Ikehara, Minoru (author)Variation in leaf colour (green, red and grey) of mosses and lake benthic mats in Antarctica is often linked to water stress and ultraviolet light (UV-B) exposure. Changes in the abundance of organic compounds, such as pectin and phenols, are associated with mechanisms protecting against desiccation and UV radiation. However, the function of...journal article 2023
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Teo, Ying Shen (author), Jafari, Iman (author), Liang, Fei (author), Jung, Youmi (author), van der Hoek, J.P. (author), Ong, Say Leong (author), Hu, Jiangyong (author)The UV/Cl2 process (also known as chlorine photolysis, which is the combination of chlorine and simultaneous irradiation of UV light) is conventionally applied at acidic mediums for drinking water treatment and further treatment of wastewater effluents for secondary reuse. This is because the quantum yield of HO• from HOCl (ϕHO•, 254 = 1.4) is...journal article 2022
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Pei, Zhongshi (author), Xu, Meng (author), Cao, Jiwei (author), Feng, Decheng (author), Hu, Wei (author), Ren, Junda (author), Jing, R. (author), Yi, Junyan (author)Asphalt aging often leads to rapid degradation of road performance, which seriously affects the service life of asphalt pavement. Exploring the influence of asphalt oil sources, asphalt grades, and filler types on asphalt microcharacteristics in the asphalt aging process can provide an essential reference to guide asphalt pavement maintenance...journal article 2022
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Fan, J. (author), Jing, Zhou (author), Cao, Yixing (author), Ibrahim, Mesfin Seid (author), Li, Min (author), Fan, Xuejun (author), Zhang, Kouchi (author)With their advantages of high efficiency, long lifetime, compact size and being free of mercury, ultraviolet light-emitting diodes (UV LEDs) are widely applied in disinfection and purification, photolithography, curing and biomedical devices. However, it is challenging to assess the reliability of UV LEDs based on the traditional life test or...journal article 2021
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Zhang, Liang (author), Li, Pengfei (author), Hu, Guanfeng (author), Zhang, Sufeng (author), Hong, Bin (author), Wang, H. (author), Wang, Dawei (author), Oeser, Markus (author)As an environmentally friendly alternative for the production of high-performance modified asphalt by chemical reactions, a liquid-state polyurethane-precursor-based reactive modifier (PRM) was developed and employed in the asphalt modification. In contrast to the traditional solid bitumen modifier, for example, rubber and thermoplastic...journal article 2021
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Barstow, M. A. (author), Aigrain, S. (author), Barstow, J. K. (author), Barthelemy, M. (author), Evans, C. (author), Ferrari, M. (author), Garcia, M. (author), Rossi, L. (author), Stam, D.M. (author)One of the most exciting scientific challenges is to detect Earth-like planets in the habitable zones of other stars in the galaxy and search for evidence of life. During the past 20 years the detection of exoplanets, orbiting stars beyond our own, has moved from science fiction to science fact. From the first handful of gas giants, found...journal article 2021
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Lut, Jasper-Jan (author), Goddijn, Michael (author)The current COVID-19 pandemic shows the necessity of personal protective equipment and face masks. In the project, a filter module with an in-situ ultraviolet-sterilization technique is designed that can serve as a new kind of smart personal protective equipment (SPPE). This technique is not used in wearable devices as of yet. The project thus...bachelor thesis 2020
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el Mansouri, B. (author), van Driel, W.D. (author), Zhang, Kouchi (author)Nowadays many applications require optical detection of some sorts, ranging from civil to military fields. Depending on the optical source, each sensing element needs to have distinct properties with the spectral range at the top. Choices such as sensitivity and environment play an equally important role, if not more important. The properties of...book chapter 2020
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Dwivedi, P. (author), Pereira, S.F. (author), Urbach, Paul (author)Wavefront aberration measurements are required to test an extreme ultraviolet (EUV) imaging system. For a high-NA EUV imaging system, where conventional wavefront-sensing techniques show limitations, ptychography can be used for this purpose. However, at the wavelength region of EUV (i.e., 13.5 nm), the position accuracy of the scanning mask...journal article 2019
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Ilyas, Huma (author), Masih, Ilyas (author), van der Hoek, J.P. (author)This paper presents a comprehensive and critical comparison of 10 disinfection methods of swimming pool water: chlorination, electrochemically generated mixed oxidants (EGMO), ultraviolet (UV) irradiation, UV/chlorine, UV/hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), UV/H<sub>2</sub>O<sub>2</sub>/chlorine, ozone (O<sub>3</sub>)/chlorine, O...review 2018
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Trifunovic, M. (author), Sberna, P.M. (author), Shimoda, T (author), Ishihara, R. (author)Printing of electronics has been gaining a lot of attention over the past decade as a low cost alternative to conventional electronic fabrication methods. A significant development in this area was the possibility to print a silicon precursor, polydihydrosilane, which can directly be transformed into polycrystalline silicon by an excimer laser...journal article 2017
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Koladouz Esfahani, Z. (author), Tohidian, M. (author), van Zeijl, H.W. (author), Kolahdouz, Mohammadreza (author), Zhang, Kouchi (author)Given the performance decay of high-power light-emitting diode (LED) chips over time and package condition changes, having a reliable output light for sensitive applications is a point of concern. In this study, a light feedback control circuit, including blue-selective photodiodes, for blue/ultraviolet (UV) LED, has been designed and...journal article 2017
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Wang, Zongping (author), Chen, Yiqun (author), Xie, Pengchao (author), Shang, R. (author), Ma, Jun (author)Cyanobacteria blooms in source waters have become a worldwide issue for drinking water production. UV-activated persulfate (UV/PS) technology was firstly applied to remove cultivated Microcystis aeruginosa (M. aeruginosa) in bench scale. The presence of persulfate significantly enhanced both cytoclasis and algal organic matter mineralization...journal article 2016
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Nikzad, Shouleh (author), Hoenk, Michael (author), Jewell, April D. (author), Hennessy, John J. (author), Carver, Alexander G. (author), Jones, Todd J, (author), Goodsall, Timothy M. (author), Hamden, Erika T. (author), Bulmer, J. (author), Charbon-Iwasaki-Charbon, E. (author), Padmanabhan, Preethi (author), Hancock, Bruce (author), Bell, L. Douglas (author)Ultraviolet (UV) studies in astronomy, cosmology, planetary studies, biological and medical applications often require precision detection of faint objects and in many cases require photon-counting detection. We present an overview of two approaches for achieving photon counting in the UV. The first approach involves UV enhancement of photon...review 2016
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Chen, Yiqun (author), Xie, Pengchao (author), Wang, Zongping (author), Shang, R. (author), Wang, Songlin (author)The performance of UV-activated persulfate (UV/PS) technology as preoxidation process to enhanceMicrocystis aeruginosa removal by subsequent coagulation-sedimentation was firstly evaluated. Theresults demonstrate that UV/PS preoxidation could successfully promote coagulation of algae cellsthrough the effective neutralization of zeta potential,...journal article 2016
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