The aim of this research is to investigate experimentally the characteristics of the convective heat transfer and exergy analysis of pure water and water based Al2O3 nanofluid through helical coiled tubes (HCTs) and conical coiled tubes (CCTs) inside shell and coil heat exchangers. HCT and CCT fabricated with different coil torsions (λ) ranges from 0.0202 to 0.052 with different two angles (0° and 45°) while have the same curvature ratio (δ = 0.0564). The effects of mean coil torsion, the cone angle and nanoparticles volume concentration on the thermal performance were investigated. Results indicated that the overall heat transfer coefficient (Uov), convection heat transfer coefficient (ht), the tube side Nusselt number (Nut), effectiveness (ɛ) and exergy efficiency (ηex) of nanofluids are higher than those of the pure water at same flow condition, and this increase goes up with the increase in particle volume concentration (ϕ). The results also showed that Uov, ht, Nut, ɛ and ηex increases by decreasing the coil torsion from 0.052 to 0.0202. Correlations for Nut as a function of the investigated parameters are obtained.

The Xylariaceae is one of the best-known pyrenomycete families (Ascomycota) and is distributed throughout the world. The majority are wood inhabitants and are prevalent in tropical and subtropical regions. Halorosellinia oceanicum is the most widely distributed in mangroves and can be regarded as truly manglicolous being frequently recorded as the dominant member of the family in such environments in S.E. Asia. In Malaysian mangroves, members of the Xylariaceae have been found to be numerically important with up to 9% present in one mangrove ecosystem. A further twelve xylariaceous genera are reported as occurring as their teleomorphs in mangrove forest and their immediate surroundings including Anthostomella, Astrocystis, Biscogniauxia, Camillea, Daldinia, Fasciatispora, Hypoxylon, Kretzschmaria, Nemania, Nipicola, Rosellinia and Xylaria. Furthermore, the presence of species from a number of these taxa, especially species of Anthostomella and Xylaria, are regularly isolated as endophytes from a variety of mangrove plant species. Mangrove Xylariaceae are also well known for their ability to produce novel and often bioactive metabolites.

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The present study was carried out at Marine Finfishes Hatchery located at the 21 Km. west of Alexandria, Alexandria governorates. The hatchery belongs to the General Authority for Fish Resources Development (GAFRD), Ministry of Agriculture and Land Reclamation, Egypt. The study aimed to study the effect of female body weights on reproductive traits of European seabass (Dicentrarchus labrax). The experimental period extended during the period from December 2020 to Abril 2021. A total number of 30 females as parent stock of European seabass representing three weight groups up to 1500 gm, >1500-2000 gm and > 2000-2500 gm for groups 1, 2, and 3, respectively (10 each) were stocked in three fiberglass circular tanks (at diameter 2.5m and about size 10m 3 ).Total egg weight (g) per female (EW/F) and egg diameter (µm) (ED) were significantly affected by female weights groups. Absolute and relative fecundity were 56001.10, 60469.10 and 65368.69; 47.51, 43.35 and 38.40 for groups 1, 2 and 3, respectively. Female body weights had significant effect on both absolute and relative fecundity. Hatchability percentage were found to be 63.31, 64.15 and 64.36 % for the three female weights groups 1, 2 and 3, respectively.

In order to boost the heat transfer rate in a conical coiled tube (CCT) using an active technique, a solenoid valve was placed ahead of the CCT and employed as a pulse generator in this research. Experimentally, the effect of pulsation on heat transfer and pressure drop in the CCT was investigated. Experiments were conducted for pulsating flow throughout a Womersley number (Wo) range of 30–48, which corresponds to a pulsating frequency of 4–10 Hz, a Dean number (De) of 1148–2983, and a coil torsion (λ) of 0.02–0.052. Results revealed that pulsating flow yields larger Nu values than steady flow. A rise in heat transfer characteristics is achieved by decreasing both the pulse frequency and the coil torsion. A pulsating flow at 4 Hz (Wo = 30) was shown to promote heat transfer by the most of all the examined frequencies. The average Nu increases as De increases, although the friction factor often decreases as De increases. When the coil torsion is reduced from 0.052 to 0.02 while maintaining the same De and Wo, the average Nu and ƒ increase by 23% and 30%, respectively. A correlation for the average Nusselt number and friction factor was presented, taking frequency and coil torsion into account.