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The transient plane source (TPS) method heat transfer model was established. A body-fitted coordinate system is proposed to transform the unstructured grid structure to improve the speed of solving the heat transfer direct problem of the winding probe. A parallel Bayesian optimization algorithm based on a multi-objective hybrid strategy (MHS) is proposed based on an inverse problem. The efficiency of the thermophysical properties inversion was improved. The results show that the meshing method of 30° is the best. The transformation of body-fitted mesh is related to the orthogonality and density of the mesh. Compared with parameter inversion the computational fluid dynamics (CFD) software, the absolute values of the relative deviations of different materials are less than 0.03%. The calculation speeds of the body-fitted grid program are more than 36% and 91% higher than those of the CFD and self-developed unstructured mesh programs, respectively. The application of body-fitted coordinate system effectively improves the calculation speed of the TPS method. The MHS is more competitive than other algorithms in parallel mode, both in terms of accuracy and speed. The accuracy of the inversion is less affected by the number of initial samples, time range, and parallel points. The number of parallel points increased from 2 to 6, reducing the computation time by 66.6%. Adding parallel points effectively accelerates the convergence of algorithms. [ABSTRACT FROM AUTHOR]

Metallic phase (1T) MoS2 has been regarded as an ideal catalytic material for the hydrogen evolution reaction (HER) due to its high active site density and favorable electrical conductivity. However, the preparation of 1T-phase MoS2 samples requires tough reaction conditions and 1T-MoS2 has poor stability under alkaline conditions. In this work, 1T-MoS2/NiS heterostructure catalysts grown in situ on carbon cloth were prepared by a simple one-step hydrothermal method. The obtained MoS2/NiS/CC combines the advantages of high active site density and a self-supporting structure, achieving stable 77% metal phase (1T) MoS2. The combination of NiS and 1T-MoS2 enhances the intrinsic activity of MoS2 while the electrical conductivity is improved. These advantages enable the 1T-MoS2/NiS/CC electrocatalyst to have a low overpotential of 89 mV (@10 mA cm−2) and a small Tafel slope of 75 mV dec−1 under alkaline conditions and provide a synthetic strategy of stable 1T-MoS2-based electrocatalysts for the HER by a heterogeneous structure. [ABSTRACT FROM AUTHOR]

Settlement and metamorphosis is the key stage during which Haliotis discus hannai larvae change from planktonic to benthic life. Larvae tend to be highly sensitive to changes in the external environment, which can result in increased mortality. In the aquaculture industry, increasing the metamorphosis rate of larvae is considered to be a critical factor for increasing yield. In this study, we modified a recirculating aquaculture system (RAS) for dense rearing of abalone larvae. We set up five density groups (1, 5, 10, 20 and 40 ind/ml) and compared the effects of traditional aquaculture (TA) and the RAS on the hatching success rate, metamorphosis rate and the expression levels of metamorphosis‐related genes. At stocking densities of 1, 5 and 10 ind/ml, the survival rate, metamorphosis rate and expression levels of MIRP, α2ADR and DopR2 in both culture modes were significantly higher than those in the 20 and 40 ind/ml densities (p < 0.05). The metamorphosis rate and survival rate of larvae in the RAS groups were significantly higher than those in the TA groups (p < 0.05). Under TA at the 40 ind/ml stocking density, the dissolved oxygen concentration in the water declined and the TAN concentration significantly increased (p < 0.05). As the stocking density increased, the size of metamorphosed larvae under each mode tended to increase in both culture modes. In particular, when the density was highest, the time required for metamorphosis was significantly extended (p < 0.05). Based these results, use of the RAS with stocking density of 10 ind/ml would maintain a stable aquaculture water environment, prevent fertilized eggs from hatching or becoming densely aggregated before larval metamorphosis, and significantly increase the stocking density per unit water. These results provide an important reference for scaling up reproduction of larval abalone and further developing the culture mode for this economically important shellfish. [ABSTRACT FROM AUTHOR]