3 research outputs found
Quantum transport in nanostructured thermoelectric generator
No full textThis thesis report is submitted in partial fulfillment of the requirements for the degree of Bachelor of Science in Electrical and Electronic Engineering, 2016.Cataloged from PDF version of thesis report.Includes bibliographical references (page 58-64).In this study, we found thermoelectric figure of merit (ZT) at different room temperatures which performed better than conventional temperature. From a transition metal dichalcogenide material MoS2 we got the highest ZT value of 4.392 at 300K. Besides this, in metal oxide such as ZnO gives the highest ZT value of 1.7108 at 310K. We have also studied Si-n Type, Si-p Type and SiGe which gives the value of ZT 2.405, 2.850 and 2.320 respectively at 300K.This study represents a bona fide study of thermoelectric materials accompanied by the modeling and simulations of an asymmetric thermoelectric device structure. The thermoelectric module will possess attributes such as a novel module design and a room temperature range rather than conventional high temperature modules. Electro-thermal interaction is commonly considered only as a matter of Joule heating. In addition, the Seebeck, Peltier and Thomson effects are significant in materials with high thermoelectric figure of merit ZT. The materials that are currently being used by researchers in thermoelectric devices are semiconductors and metal-oxides. These materials include Sb2Te3, PbTe, Bi2Te3, (BiSb)2Te3, SiGe, Si; which are specifically developed for conventional and high temperature ranges. And from our study we have already said that there is another class of materials that are metal dichalcogenides(MoS2) which have a good figure of merit(ZT) at room temperature. A high Seebeck coefficient , a good electric conductivity and a poor thermal conductivity are the characteristics of these materials. As a result, thermal and electrical performance of the thermoelectric module which represents a good electrical performance in thermoelectric generator.Mohammad Mobassar HossainMd. Sharif UzzamanShabab Azfar AhmedMd. Shahriar ShafatB. Electrical and Electronic Engineerin
Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study (vol 46, pg 2021, 2022)
No full textN/
Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study
No full textBackground: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak.
Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study.
Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM.
Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide
