Arc welding is accompanied by intense optical radiation emission that can be detrimental not only for the welder himself but also for people working nearby or for passersby. Technological progress advances continuously in the field of joining, so an up-to-date radiation database is necessary. Additionally, many literature irradiance data have been measured for a few welding currents or for parts of the optical spectral region only. Within this paper, a comprehensive study of contemporary metal active gas, metal inert gas, and cold metal transfer welding is presented covering optical radiation emission from 200 up to 2,700 nm by means of (spectro-) radiometric measurements. The investigated welding currents range from 70 to 350 A, reflecting values usually applied in industry. Based upon these new irradiance data, three mathematical models were derived in order to describe optical radiation emission as a function of welding power. The linear, exponential, and sigmoidal emission models depend on the process variant (standard or pulsed) as well as on the welding material (mild and stainless steel, aluminum). In conjunction with the corresponding exposure limit values for incoherent optical radiation maximum permissible exposure durations were calculated as a function of welding power. Typical times are shorter than 1 s for the ultraviolet spectral region and range from 1 to 10 s for visible radiation. For the infrared regime, exposure durations are of the order of minutes to hours. Finally, a validation of the metal active gas emission models was carried out with manual arc welding.
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http://dx.doi.org/10.1097/HP.0000000000000709 | DOI Listing |
J Am Chem Soc
January 2025
National Center for International Research on Green Optoelectronics, Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, Institute of Electronic Paper Displays, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China.
Ice melting, a common yet complex phenomenon, remains incompletely understood. While theoretical studies suggest that preexisting defects in ice generate "off-lattice" water molecules, triggering bulk ice melting, direct experimental evidence of their form has been lacking as the transparent and transient nature of ice poses significant challenges for observation with current techniques. Here, we introduce an ice-melting-induced lyophilization (IMIL) technique that employs graphene-based nanoprobes to replicate and track liquid evolution within melting bulk ice.
View Article and Find Full Text PDFLuminescence
January 2025
School of Chemical Engineering, Yeungnam University, Gyeongsan, Republic of Korea.
Crystal Violet (CV) is a vibrant and harmful dye known for its toxicity to aquatic life and potential carcinogenic effects on humans. This study explores the removal of CV through photocatalysis driven by visible light, as well as examining the antibacterial and antibiofilm characteristics of zinc oxide nanoparticles (ZnO NPs) synthesized from the aerial roots of Ficus benghalensis. Various characterization techniques were employed to confirm the optical properties, crystal lattices, and morphology of ZnO NPs.
View Article and Find Full Text PDFTheranostics
January 2025
Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan, 410008, P.R. China.
The human body is an intricate system, where diverse and complex signaling among different organs sustains physiological activities. The eye, as a primary organ for information acquisition, not only plays a crucial role in visual perception but also, as increasing evidence suggests, exerts a broad influence on the entire body through complex circuits upon receiving light signals which is called non-image-forming vision. However, the extent and mechanisms of light's impact on the body through the eyes remain insufficiently explored.
View Article and Find Full Text PDFTheranostics
January 2025
Departments of Radiology, Washington University in St. Louis, MO 63110, USA.
Cancer remains a leading cause of mortality, with aggressive, treatment-resistant tumors posing significant challenges. Current combination therapies and imaging approaches often fail due to disparate pharmacokinetics and difficulties correlating drug delivery with therapeutic response. In this study, we developed radionuclide-activatable theranostic nanoparticles (NPs) comprising folate receptor-targeted bimetallic organo-nanoparticles (Gd-Ti-FA-TA NPs).
View Article and Find Full Text PDFHeliyon
January 2025
Department of Mechanical Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
Background: The development of heat transfer devices used for heat conversion and recovery in several industrial and residential applications has long focused on improving heat transfer between two parallel plates. Numerous articles have examined the relevance of enhancing thermal performance for the system's performance and economics. Heat transport is improved by increasing the Reynolds number as the turbulent effects grow.
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