In this work, the influence of semi-conductive SiC nanoparticles on the AC breakdown voltage and partial discharge development in natural ester oil FR3 is examined. Primarily, the dielectric constant and the electrical conductivity of the nanoparticles are measured following the broadband dielectric spectroscopy technique. The nanoparticles are added into the matrix following the ultrasonication process in three weight percentage ratios in order for their effect to be evaluated as a function of their concentration inside the base oil. The processing of the results reveals that the nanofluid containing SiC nanoparticles at 0.004% / demonstrates the highest AC dielectric strength improvement and shows the greatest resistance to the appearance of partial discharge activity. The mechanisms behind the aforementioned results are discussed in detail and confirmed by the broadband dielectric spectroscopy technique, which reveals that this particular nanofluid sample is characterized by lower dielectric constant and electrical conductivity than the one with double the weight percentage ratio.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8780698 | PMC |
http://dx.doi.org/10.3390/nano12020269 | DOI Listing |
Sensors (Basel)
January 2025
School of Electrical and Electronic Engineering, Harbin University of Science and Technology, Harbin 150080, China.
This study addresses the challenges of electromagnetic interference and unstable signal transmission encountered by traditional sensors in detecting partial discharge (PD) within stator slots of large motors. A novel Extrinsic Fabry-Perot Interferometer (EFPI) sensor with a vibration-coupling air gap was designed to enhance the narrowband resonant detection sensitivity for PD ultrasonic signals by optimizing the diaphragm structure and coupling interface. The sensor features a quartz diaphragm with a thickness of 20 μM, an effective constrained radius of 0.
View Article and Find Full Text PDFEur J Trauma Emerg Surg
January 2025
Department of Intensive Care Medicine, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
Purpose: In patients with traumatic brain injury (TBI), adequate oxygenation is crucial to optimize survival and neurological outcome. However, supranormal oxygen partial pressure (PaO) only leads to minor increase in cerebral oxygen delivery but can cause numerous pathophysiological disturbances. Therefore, we aimed to study effects of hyperoxia on patient outcome and identify optimum PaO ranges.
View Article and Find Full Text PDFJ Cardiovasc Dev Dis
January 2025
Emergency Department, Leszek Giec Upper-Silesian Medical Centre of the Medical University of Silesia in Katowice, 40-635 Katowice, Poland.
Paradoxical embolism occurs when a clot originates in the venous system and traverses through a pulmonary or intracardiac shunt into the systemic circulation, with a mortality rate of around 18%. The risk factors for arterial embolism and venous thrombosis are similar, but different disease entities can lead to a hypercoagulable state of the blood, including antithrombin III (AT III) deficiency. We report the case of a 43-year-old man with a massive central pulmonary embolism with a rider embolus and concomitant aortic arch embolism with involvement of the brachiocephalic trunk, bilateral subclavian and axillary arteries, and the right vertebral artery, followed by a secondary ischaemic stroke.
View Article and Find Full Text PDFWorld J Gastrointest Endosc
January 2025
Department of Gastroenterology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230001, Anhui Province, China.
Background: Patients diagnosed with esophageal mucosal bridges often experience symptoms such as chest pain and dysphagia, which pose considerable challenges for endoscopic surgical interventions.
Case Summary: We present a case involving early-stage esophageal cancer discovered in a resting room, notable for the rare manifestation of esophageal mucosal bridging. Following a comprehensive multidisciplinary discussion and the development of a treatment strategy, we proceeded with endoscopic submucosal dissection for the patient.
Front Oncol
January 2025
Department of Gastroenterology, Shengli Oilfield Central Hospital, Dongying, China.
Introduction: Gastric glomus tumor is a rare submucosal mesenchymal tumor with no distinct features on endoscopy. In clinical practice, it is often treated with laparoscopic partial gastrectomy. Here, we report a case of gastric glomus tumor successfully resected using a combination of gastroscopy and laparoscopy.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!