The multi-hole probe can measure the velocity and three-dimensional direction of the flow field at the same time, so it is often used to measure the three-dimensional flow field. Compared with other flow field measuring instruments, the multi-hole probe has stronger environmental adaptability and stability, and can better measure the three-dimensional flow field of the middle atmosphere. Therefore, a hemispherical 7-hole probe was designed, a pressure-velocity parameterized equation was established based on the theory of flow around a sphere, and a new calibration method was developed based on this. The calibration is carried out in a subsonic low speed wind tunnel, multiple combinations of flow parameters (inflow velocity and flow angles) are adjusted during the calibration. The results are compared with the numerical simulation results, both are quite close, with a speed measurement deviation of less than 5% and an angle measurement deviation of less than 1°. Our results establish the practicality of the hemispherical 7-hole probe and the simplified calibration procedure, both of which improve calibration efficiency and lower probe calibration costs.
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http://dx.doi.org/10.1038/s41598-022-16929-2 | DOI Listing |
Mikrochim Acta
January 2025
Centre for Micro and Nano Devices, Department of Physics, COMSATS Institute of Information Technology, Islamabad, 44500, Pakistan.
Traditional surface-enhanced Raman scattering (SERS) substrates seeking uniformity and reproducibility of the Raman signal often assume and require that hot spots remain consistently stable during Raman testing. Recently, the non-uniform accumulation in SERS sample pre-concentration strategies have inspired the direct use of self-healing noble metal aerogels (NMAs), as the sample pretreatment presented in this work, and uncovered more diverse Raman information of substances during the dynamic process of laser irradiation. Rare characteristic peaks such as 820 cm⁻ for R6G within a specific concentration range were observed, and potential processes including R6G dimerization and desorption were analyzed.
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River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL), Sion, Switzerland.
Unlabelled: Glacier-fed streams are permanently cold, ultra-oligotrophic, and physically unstable environments, yet microbial life thrives in benthic biofilm communities. Within biofilms, microorganisms rely on secondary metabolites for communication and competition. However, the diversity and genetic potential of secondary metabolites in glacier-fed stream biofilms remain poorly understood.
View Article and Find Full Text PDFNanoscale
January 2025
School of Natural Sciences, Faculty of science and engineering, Macquarie University, Sydney, NSW 2109, Australia.
As the prevalence of cancer is escalating, there is an increased demand for early and sensitive diagnostic tools. A major challenge in early detection is the lack of specific biomarkers, and a readily accessible, sensitive and rapid detection method. To meet these challenges, cancer-derived small extracellular vesicles (sEVs) have been discovered as a new promising cancer biomarker due to the high abundance of sEVs in body fluids and their extensive cargo of biomarkers.
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January 2025
Division of Crop Protection, ICAR-Indian Institute of Spices Research, Marikunnu, Kozhikode, 673012 India.
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December 2024
Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Centre of Atmospheric Environment and Equipment Technology (CIC-AEET), School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China. Electronic address:
Ferrate (Fe(VI)) is a widely used water purifier and is easily affected by external factors. Given that the actual water environment conditions are complicated, this study designed an oxygen-doped carbon nitride (CNO) with rich electron sites to explore whether direct electron transfer promotes the degradation efficiency of Fe(VI) for pollutants under visible light. For comparison, we also prepared phosphorus-doped carbon nitride (CNP), which has electron-deficient sites and indirect electron transfer.
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