Search

In this work, elevators shaped by NACA 0012 were deployed on the outer surfaces of tubes in a Flat-tube-and-fin heat exchanger, and their structural details were numerically investigated. Then, following an infrared experiment validation, heat transfer coefficient, pressure loss and JF factor were numerically compared to confirm performance enhancement. It is found that the maximum deviations between numerical and experimental data, 6,31 % of heat transfer coefficient and 3,84 % of pressure loss, secure the accuracy of the following comparison, and the maximum increases of heat transfer coefficient, pressure loss, and JF factor are 7,20 %, 0,07 %, and 7,09 % at 12 m/s, respectively.

T he thermal performance of Liquid-cooled plate (LCP) can be improved by using different kinds of materials and coolants. Suitable and effective coolant can bring better cooling capacity to cope with the impact of high temperature on IGBT chips, and improve the safety and service life of new energy metallurgical loaders. In this context, the recent progress of the effects of traditional coolants, nano-fluids, ethylene glycol and oil on the heat transfer capacity of the liquid cooling plate is reviewed in detail. Nanofluids have been identified as the most prominent cooling method at present because of their good thermal conductivity. In addition, the considerations and advantages and disadvantages of using different coolants are discussed in depth.

BACKGROUND: Blood removed from organs during deceased donor organ procurement is routinely discarded but is a potential resource for donor-specific transfusion (DST) in subsequent liver transplantation (LT). This study retrospectively analyses the impact of DST on intraoperative bank blood product usage, long-term graft, and patient survival, as well as frequency of rejection post-LT. METHODS: A total of 992 adult LT performed from 1993 to 2018 in a single quaternary center were included. Intraoperative blood product usage, patient, and graft survival, as well as acute and chronic rejection were assessed in patients who received blood retrieved from the organ donor, the "donor blood" (DB) group (n = 437) and patients who did not, the "no donor blood" (NDB) group (n = 555). RESULTS: Processing of DB ensured safe levels of potassium, magnesium, and insulin. There were fewer units of bank red blood cells transfusion required in the DB group compared to NDB group (2 vs. 4 units, P = .01). Graft survival was significantly superior in the DB group (10-year survival 75% vs. 69%, respectively, P = .04) but DST was not an independent predictor of graft survival. There was no significant difference in patient survival or rejection between the groups. There was no difference in treated, biopsy-proven rejection between the two groups. CONCLUSIONS: This is the first large-cohort study assessing long-term outcomes of intraoperative DST in LT. The collection of organ donor blood and subsequent use in LT recipients appeared feasible with appropriate quality checks ensuring safety. DST resulted in a reduction in the use of packed red blood cells. There was no difference in the rate of rejection or graft or patient survival.

Design and implementation of efficient radiating omnidirectional loops have been studied. A modified shielded loop with four feeding sections has been proposed. Measured results show that good impedance matching, omnidirectional radiation pattern, and good radiation efficiency have been achieved. A combination of the proposed loop and a half-wavelength E-dipole in a collocated position has also been examined. Extremely low correlation achieved indicates that this antenna can be used as a reference for evaluating the MIMO performance of future collocated polarization diversity based antennas, and a measurement antenna for measuring the polarization at the mobile as well., QC 20121221