Numerical simulation of casting filling process with complex shape is time-consuming. Compared with the traditional SOLA-VOF method, the lattice Boltzmann method (LBM) calculates the pressure field by particle distrib...
Numerical simulation of casting filling process with complex shape is time-consuming. Compared with the traditional SOLA-VOF method, the lattice Boltzmann method (LBM) calculates the pressure field by particle distribution functions instead of the correction of the velocity and pressure fields, which greatly simplifies the calculation process. In addition, the LBM provides a flexible approach which can be easily parallelized. In this study, the LBM is employed to simulate casting filling process. An implementation of a volume-of-fluid (VOF) method within the lattice Boltzmann framework is proposed to capture the free surface of the casting filling process. A Smagorinsky large eddy simulation (LES) model is adopted to improve the numerical stability of the LBM. An adaptive time stepping technique is implemented to ensure an efficient and stable simulation. The model is validated by the experimental and simulation results of Campbell box filling process. The filling process of complex casting is simulated, and the result is compared with the filling process obtained by the SOLA-VOF method. The prediction accuracy and reliability of free surface profile is analysed.
One-dimensional (1D) van der Waals (vdW) materials have garnered significant attention for their unique structures and properties, making them promising candidates for various applications in optoelectronics, catalysi...
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The discovery of Mn-Ca complex in photosystem II stimulates research of manganese-based catalysts for oxygen evolution reaction (OER). However, conventional chemical strategies face challenges in regulating the four e...
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The influences of crystallinity and surface modification of calcium phosphate nanoparticles (nCaP) on their drug loading capacity and drug release profile were studied in the present investigation. The CaP nanoparticl...
The influences of crystallinity and surface modification of calcium phosphate nanoparticles (nCaP) on their drug loading capacity and drug release profile were studied in the present investigation. The CaP nanoparticles with different crystallinity were prepared by precipitation method under different temperatures. CaP nanoparticles with lower crystallinity exhibited higher drug loading capacity. The samples were characterized by XRD, FT-IR, SEM, TEM and BET surface area analyzer respectively. The drug loading capacity of nCaP was evaluated to tetracycline hydro-chloride (TCH). The internalization of TCH loaded nCaP in cancer cell was observed by florescence microscope. nCaP could be stabilized and dispersed in aqueous solution by poly(acrylic acid) surface modification agent, leading to enhanced drug loading capacity. The drug release was conducted in different pH environment and the experimental data proved that nCaP were pH sensitive drug carrier, suggesting that nCaP could achieve the controlled drug release in intracellular acidic environment. Furthermore, nCaP with higher crystallinity showed lower drug release rate than that of lower crystallinity, indicating that the drug release profile could be adjusted by crystallinity of nCaP. nCaP with adjustable drug loading and release properties are promising candidate as drug carrier for disease treatment.
Zinc-ion batteries (ZIB) present great potential in energy storage due to low cost and high safety. However, the poor stability, dendrite growth, and narrow electrochemical window limit their practical application. He...
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Zinc-ion batteries (ZIB) present great potential in energy storage due to low cost and high safety. However, the poor stability, dendrite growth, and narrow electrochemical window limit their practical application. Herein, we develop a new eutectic electrolyte consisting of ethylene glycol (EG) and ZnCl 2 for dendrite-free and long-lifespan ZIBs. The EG molecules participate in the Zn 2+ solvation via coordination and hydrogen-bond interactions. Optimizing the ZnCl 2 /EG molar ratio (1 : 4) can strengthen intermolecular interactions to form [ZnCl(EG)] + and [ZnCl(EG) 2 ] + cations. The dissociation–reduction of these complex cations enables the formation of a Cl-rich organic–inorganic hybrid solid electrolyte interphase film on a Zn anode, realizing highly reversible Zn plating/stripping with long-term stability of ≈3200 h. Furthermore, the polyaniline||Zn cell manifests decent cycling performance with ≈78 % capacity retention after 10 000 cycles, and the assembled pouch cell demonstrates high safety and stable capacity. This work opens an avenue for developing eutectic electrolytes for high-safety and practical ZIBs.
Zr2Al4C5/SiC composite ceramics were successfully fabricated from the powder mixture of Zr, Al, C and SiC by spark plasma sintering method. The composition-dependent densification, phase evolution, microstructure and ...
Zr2Al4C5/SiC composite ceramics were successfully fabricated from the powder mixture of Zr, Al, C and SiC by spark plasma sintering method. The composition-dependent densification, phase evolution, microstructure and mechanical properties of the composite ceramics were studied. With increasing the SiC content in the starting powder mixture, the densification behavior of sintered samples was promoted. It is found that the as-sintered products are mainly composed of Zr2Al4C5 matrix and SiC reinforcement, and the fine SiC particles tend to disperse on the matrix grain boundaries. Besides, the addition of SiC particles can evidently hinder the coarsening of Zr2Al4C5 grains. Both the Vickers hardness and Young's modulus of composites ceramics gradually increase as increasing the SiC content. The fracture toughness of the composites decreases first then increases with the increase in the SiC and the Zr2Al4C5/30vol%SiC sample possesses the maximum value of 4.4MPam1/2.
ZrB2/ZrxAlyCz composite ceramics with different volume contents of ZrxAlyCz were fabricated by the spark plasma sintering. The sintering behavior, microstructure, mechanical properties and oxidation resistance were st...
ZrB2/ZrxAlyCz composite ceramics with different volume contents of ZrxAlyCz were fabricated by the spark plasma sintering. The sintering behavior, microstructure, mechanical properties and oxidation resistance were studied. The results indicated that sinterability of the composites was remarkably improved by addition of ZrxAlyCz compared to the single-phase ZrB2 ceramic. As the content of ZrxAlyCz increased, both the Vickers hardness and Young's modulus of the composites first increased and then decreased. The fracture toughness of the ZrB2-40vol% ZrxAlyCz composite was 3.56 MPam1/2, which increased by approximately 70% compared to the monolithic ZrB2 ceramic. As increasing the content of ZrxAlyCz, the oxidation resistance of composite ceramics was obviously enhanced. The oxidation-resulted increase in weight of composite ceramic with 20vol% ZrxAlyCz was the best performance in oxidation resistance at 1500 °C. The high-temperature oxidation resulted in dense and stable Al-B-O glass due to adding ZrxAlyCz into the composite ceramics, those resulting products effectively blocked the oxygen atoms entering into the ceramic matrix.
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