Nanjing University of Science and Technology

About: Nanjing University of Science and Technology is a education organization based out in Nanjing, China. It is known for research contribution in the topics: Catalysis & Computer science. The organization has 31581 authors who have published 36390 publications receiving 525474 citations. The organization is also known as: Nánjīng Lǐgōng Dàxué & Nánlǐgōng.

Crushing analysis and multiobjective crashworthiness optimization of foam-filled ellipse tubes under oblique impact loading

Abstract: In this paper, a novel foam-filled ellipse tube (FET) is proposed and compared with other hollow and foam-filled tubes with different cross-sections under multiple loading angles, which include square, circle and rectangle. First, finite element analyses of these tubes reveal that the FET tube has the best crashworthiness under multiple loading angles. Second, design of experiments (DOE) was used to analyze the parameters that radial rate f, thickness of wall t and foam density ρ f . Third, the Non-dominated Sorting Genetic Algorithm (NSGA-II) is used to optimize the FET tube, in which the optimal parameter variation is sought for maximizing specific energy absorption (SEA) and minimizing peak crush force (PCF) under multiple loading angles. The optimized FET tube exhibits better crashworthiness than the origin FET tube and other tubes with different cross-section, indicating that the FET tube can be a potential energy absorber especially under oblique impact loading.

New normalized Rortex/vortex identification method

Abstract: A new vortex identification criterion, named ΩR, is proposed for the normalization of Rortex, using the idea of the Omega method (Ω). ΩR is a normalized function from 0 to 1, which measures the relative rotation strength on the plane perpendicular to the local rotation axis. The advantages of the proposed ΩR method can be summarized as follows: (1) ΩR is from 0 to 1 and can be further used in statistics and correlation analysis as a physical quantity. (2) ΩR can distinguish the rotational vortices from the shear layers, discontinuity structures, and other non-physical structures. (3) ΩR is quite robust and can be always set as 0.52 to capture vortex structures in different cases and at different time steps.

Electronic structure and optical properties of graphene/stanene heterobilayer

Abstract: The structural, electronic and optical properties of the graphene hybrid with stanene, the tin counterpart of graphene, are investigated by means of density functional calculation with the observation of band gap opening and enhanced visible light response The lattice mismatch between graphene and stanene is taken into consideration and several stacking methods for model construction are proposed to study the possible effects The Dirac feature can be observed in this bilayer system with relatively stronger interlayer interaction than weak van der Waals forces, which is ascribed to the unsaturated p orbital of stanene Despite the mutual semi-metal nature of graphene and stanene, it is significant to note a band gap opening and the electrical neutrality of the bilayer The combination of high carrier mobility of graphene and the excellent spin Hall effect of stanene is expected to coexist in the bilayer structure In addition, we found that the stanene monolayer has a relatively lower work function than graphene and more importantly, it exhibits more pronounced optical absorption than graphene The results indicate that a graphene/stanene heterobilayer will facilitate the performance of stanene related spintronic devices and is therefore a good candidate for photoelectronic devices