In this study, electric field and magnetic flux density pollution levels were measured in southern Africa, a case of Blantyre City in Malawi, between 2020 and 2021. Sixty short-term measurements were performed using Trifield Electro Magnetic Frequency meter model TF2 in 30 different locations. Five high-population-dense sampling points were selected from school campuses, hospitals, industrial areas, markets, residential areas, and within the commercial and business center (CBC) of Blantyre. Electric field and magnetic flux density pollution monitoring was conducted between 10:00-12:00 h and 17:00-19:00 h for short-range analysis. Short-range results show that the maximum measured electric field pollution were 249.24 mV/m and 207.85 mV/m between 10:00-12:00 and 17:00-19:00 respectively, which are below the public limits of 4200.00 mV/m for public exposure. Similarly, maximum short-range results for magnetic flux density were 0.073 G and 0.057 G between 10:00-12:00 and 17:00-19:00 respectively which are below the public limits of 2 G for public exposure. Both measured electric and magnetic flux density were compared with the International Commission on Non-Ionizing Radiation Protection (ICNIRP), World health organization (WHO), and Institute of electrical and electronics engineers (IEEE). It was determined that all measured values for both electric and magnetic flux density were smaller than set limits for non-ionizing radiation for both public and occupation health. More importantly, these background measurements establish a baseline for future changes to be compared against public safety.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10001587 | PMC |
http://dx.doi.org/10.3390/ijerph20054413 | DOI Listing |
Bioelectromagnetics
January 2025
Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland.
Although static magnetic fields (SMFs) have been reported to induce only minimal biological effects, it has been proposed that they may alter the effects of other agents, such as ionizing radiation. We sham-exposed or exposed human SH-SY5Y neuroblastoma cells to 0.5-, 1.
View Article and Find Full Text PDFLight Sci Appl
January 2025
State Key Laboratory of Advanced Optical Communication Systems and Networks, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China.
Non-Hermitian topological photonics plays a key role in bridging topological matter with gain and loss engineering in optics. Here we report the experimental observation of the break of chiral currents in a Hall ladder from the non-Hermiticity by constructing synthetic frequency dimension in two rings, where currents on both legs of the ladder co-propagate in the same direction. The origin of such phenomena is resulted from the interplay between the effective magnetic flux and the on-site gain and loss.
View Article and Find Full Text PDFSensors (Basel)
December 2024
Zhejiang Institute of Mechanical & Electrical Engineering Co., Ltd., Hangzhou 310051, China.
This study addresses the challenges of magnetic circuit coupling and control complexity in active radial magnetic bearings (ARMBs) by systematically investigating the electromagnetic performance of four magnetic pole configurations (NNSS, NSNS, NNNN, and SSSS). Initially, equivalent magnetic circuit modeling and finite element analysis (FEA) were employed to analyze the magnetic circuit coupling phenomena and their effects on the magnetic flux density distribution for each configuration. Subsequently, the air gap flux density and electromagnetic force were quantified under rotor eccentricity caused by unbalanced disturbances, and the dynamic performances of the ARMBs were evaluated for eccentricity along the x-axis and at 45°.
View Article and Find Full Text PDFSensors (Basel)
December 2024
College of Physics, Jilin University, Changchun 130000, China.
The sensorless vector control method of synchronous reluctance motors (SynRMs), based on extended back electromotive force (EMF) or flux observation, has been widely applied in the medium- or high-speed range. However, in the low-speed and low-current range, the extended back-EMF and flux are nearly zero. The use of the current frequency () control method can enable the motor to pass through the low-speed region, thereby ensuring that the back-EMF and flux reach a large value.
View Article and Find Full Text PDFSci Total Environ
January 2025
Research Centre of Ecology & Environment for Coastal Area and Deep Sea, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Guangdong Basic Research Center of Excellence for Ecological Security and Green Development, Guangdong University of Technology, Guangzhou 510006, China. Electronic address:
Methane leaking from the deep seabed is a primary source of carbon and energy for various microorganisms, sustaining the evolution and productivity of cold seep ecosystems. However, the dynamics of methane hydrate formation under methane seepage conditions and potential impacts on the evolution of cold seep ecosystems remain unclear. This study investigated the dynamic formation characteristics of gas hydrates within cold seep sediments by simulating the methane leakage process.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!