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In order to explore the mechanism of eccentric fractal finned tube on enhancing the solidification performance of latent heat storage unit, the solidification of paraffin in latent heat storage unit of eccentric fractal finned tube was simulated by two-dimensional unsteady state. Under the consideration of natural convection, the heat transfer characteristics of eccentric rectangular fins and eccentric fractal fins are firstly studied, and then the improvement of solidification process by two local strengthening schemes with fins on the upper part and fins on the lower part is compared. Then the influence of fin angle is studied. Finally, the lower part of the secondary branch fin with an angle of 60° was selected to add a fin strengthening structure to further strengthen the paraffin solidification process in the latent heat storage of eccentric fractal fin. Concluded that compared with eccentric rectangular finned, eccentric fractal fin shorten the coagulation time by 41.2 %, upper add fin and lower add fin both local reinforcement schemes are made the whole process of solidification rate has increased, about 1000 s, the upper encryption fin make solidification rate increased by 16.7 %, the lower encryption fin make solidification rate increased by 50 %, the total solidification time of the lower fin is basically unchanged, while the structure of the upper fin reduces the total solidification time by 15.3 %. Three structures with fin angles of 45°, 60° and 90° were simulated and the total solidification time was shortened with the increase of fin angle. Compared with the original eccentric fractal fin structure, the solidification time of the final strengthened structure is reduced by 70 %.

Intracerebral hemorrhage (ICH)-induced brain injury leads to irreversible disruption of the blood–brain barrier (BBB) and fatality brain edema with massive cell death. Although secondary damage could, in principle, be preventable, no effective treatment approaches currently exist for patients with ICH. Tempol, a catalytic scavenger of peroxynitrite (ONOO−)-derived free radicals, has been proven to ameliorate brain injury in several types of brain insults. This study aims to investigate the potential neuroprotective effect of tempol after ICH and to explore the underlying mechanisms. Collagenase-induced ICH was performed in rats. Tempol was administered immediately after ICH. The effects of tempol on ICH were evaluated by assessing neurological deficits, BBB permeability, brain edema, and apoptotic cell death. The mechanisms of action of tempol, with its clear ability on the derivative of ONOO−[3-nitrotyrosine (3-NT), ONOO−, and its derivative-mediated nitration marker] and expression of tight junction protein [zonula occludens-1 (ZO-1)], were also investigated. Perihematomal 3-NT increased significantly following ICH and expressed around vessels accompanied by reduced and discontinuous expression of ZO-1. Tempol treatment significantly suppressed 3-NT formation and preserved ZO-1 levels, and led to improvement in neurological outcomes and reduction of BBB leakiness, brain edema, and apoptosis. In conclusion, tempol has neuroprotective potential in experimental ICH and may help combat ICH-induced brain injury in patients.

Data from 895 field experiments conducted between 2000 and 2008 were analyzed to calculate yield gaps, indigenous nutrient supplies; and nutrient use efficiencies - with the goal of improving nutrient management for wheat. Results showed an average yield gap of 0.76 t/ha between attainable yields and yields with farmers' practice. Successive inputs of large amounts of nutrients have significantly increased soil nutrient supply, and therefore contribute to lower use ef- ficiencies since recommendations for N, P, and K have not been adjusted downward. [ABSTRACT FROM AUTHOR]

•A new model named phase change heat-porous medium which is suitable for composite melting is established.•The evolution of liquid phase ratio with temperature is determined by experiments.•The accuracy of the model is verified by the visualization experiment. The model can effectively predict the solid-liquid phase transition of composite PCM.