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1D and 2D carbon nanomaterials such as multi-walled carbon nanotubes (MWCNTs) and graphene nanoplatelets (GNPs) were investigated numerically. The thermophysical properties of water and nanofluids using MWCNTs in different outer diameters (ODs) and GNPs in different surface areas (SSA) were measured at an inlet temperature of 303.15 K and 0.1wt.%. The 3D geometry was solved under a fully developed turbulent flow of 6000 ≤ Re ≤ 16,000 using the model of k-ω SST via (ANSYS FLUENT 2022R2) software. Four numerical networks, Polyhedra, Polyhexacore, Hexacore, and Tetrahedral, were optimized. Moreover, seven parameters were discussed, namely wall surface temperature (Tw), heat transfer coefficient (htc), average Nusselt number (Nuavg), friction factor (f), pressure drop (ΔP), and total thermal performance index (PIth). Polyhexacore was the main grid over Polyhedra, Hexacore, and Tetrahedral with the average error (Dittus-Boelter: 2.754%, Gnielinski: 2.343%, Blasius: 1.441%, and Petukhov: 0.640%). Heat transfer increased by 18.38% with GNPs-300, 22.05% with GNPs-500, 23.25% with GNPs-750, 13.63% with CNT < 8 nm, and 11.42% with CNT 20–30 nm, relative to H2O at Re = 16,000. Pressure drop increased by about 42.01% with GNPs-300, 45.16% with GNPs-500, 44.84% with GNPs-750, 36.72% with CNT < 8 nm, and 34.39% with CNT 20-30 nm. [ABSTRACT FROM AUTHOR]

The flat-plate solar collector (FPSC) three-dimensional (3D) model was used to numerically evaluate the energy and economic estimates. A laminar flow with 500 ≤ Re ≤ 1900, an inlet temperature of 293 K, and a solar flux of 1000W/m² were assumed the operating conditions. Two mono nanofluids, CuO-DW and Cu-DW, were tested with different shapes (Spherical, Cylindrical, Platelets, and Blades) and different volume fractions. Additionally, hybrid nanocomposites from CuO@Cu/DW with different shapes (Spherical, Cylindrical, Platelets and Blades), different mixing ratios (60%+40%, 50%+50% and 40%+60%) and different volume fractions (1 volume%, 2 volume%, 3 volume% and 4 volume%) were compared with mono nanofluids. At 1 volume% and Re = 1900, CuO-Platelets demonstrated the highest pressure drop (33.312 Pa). CuO-Platelets achieved the higher thermal enhancement with (8.761%) at 1 vol.% and Re = 1900. CuO-Platelets reduced the size of the solar collector by 25.60%. Meanwhile, CuO@Cu-Spherical (40:60) needed a larger collector size with 16.69% at 4 vol.% and Re = 1900. CuO-Platelets with 967.61, CuO -- Cylindrical with 976.76, Cu Platelets with 983.84, and Cu-Cylindrical with 992.92 presented the lowest total cost. Meanwhile, the total cost of CuO -- Cu -- Platelets with 60:40, 50:50, and 40:60 was 994.82, 996.18, and 997.70, respectively. [ABSTRACT FROM AUTHOR]

The role of epidemiologic and spatiotemporal factors affecting access to care among snakebite patients in Nigeria are determined. In 2021 a total of 2,942 snakebite patients were prospectively studied at four designated Health Facilities for Managing Snakebites (HFMS). The patients came from 94 Local Government Areas (LGAs) in 12 states in northern Nigeria. It was found that 435 (14.8%) patients actually accessed care within ≤2 hours of bite although 38.0% could have reached the HFMS within the time by car. In certain areas 92% of patients would have been able to reach a secondary or tertiary facility within ≤2 hours. Similarly, 437 (14.9%) patients traveled distances of ≤20 Km to reach a designated HFMS although 86% of patients resided within 5 Km of a road network. There was longer median delay to access care (15 hours), more patients (365) and higher proportion not treated with antivenom (22%) in August the wettest month of the year. Furthermore the patients who died (47) took a median time of 48 hours compared to 11 hours among known survivors (2,649) to access care. Expanding antivenom access to other secondary and tertiary HF in high burden areas especially during peak seasons will potentially improve the outcome among patients. [ABSTRACT FROM AUTHOR]