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ZrB2-SiBCN ceramics with ZrO2additive are hot-pressed under a constant applied pressure. The densification behavior of the composites is studied in a view of creep deformation by means of the Bernard-Granger and Guizard model. With determination of the stress exponent (n) and the apparent activation energy (Qd), the specific deformation mechanisms controlling densification are supposed. Within lower temperature ranges of 1300–1400 °C, the operative mechanism is considered to be grain boundary sliding accommodated by atom diffusion of the polymer-derived SiBCN (n= 1, Qd= 123±5 kJ/mol) and by viscous flow of the amorphous SiBCN (n= 2, Qd= 249±5 kJ/mol). At higher temperatures, the controlling mechanism transforms to lattice or intra-granular diffusion creep (n= 3–5) due to gradual consumption of the amorphous phase. It is suggested that diffusion of oxygen ions inside ZrO2into the amorphous SiBCN decreases the viscosity, modifies the fluidity, and contributes to the grain boundary mobility.

Hedgehog (Hh) signaling is well known for its crucial role during development, but its specific role in individual cell lineages is less well characterized. Here, we disrupted Hh signaling specifically in melanocytes by using Cre-mediated cell-type-specific knockout of the Hh regulator suppressor of fused (Sufu). Interestingly, corresponding mice were fully pigmented and showed no developmental alterations in melanocyte numbers or distribution in skin and hair follicles. However, there were ectopic melanoblasts visible in the anterior chamber of the eye that eventually displayed severe malformation. Choroidal melanocytes remained unaltered. Surprisingly, the abnormal accumulation of anterior uveal melanoblasts was not the result of increased cell proliferation but of increased migration to ectopic locations such as the cornea. In melanoblasts in vitro, Sufu knockdown replicated the increase in cell migration without affecting proliferation and was mediated by an increased level of phosphorylated-ERK brought about by a reduction in the levels of the repressor form of GLI3. These results highlight the developmental divergence of distinct melanocyte subpopulations and may shed light on the pathogenesis of human ocular melanocytosis.

A suitable ionic liquid for methyl chloride drying experiment was screened out from 210 ionic liquids by COSMO-RS model. Moreover, the experimental mechanism of ionic liquids drying is further explained by the COSMO-RS model, and it is further confirmed by analyzing the binding energy. The solubility of methyl chloride in [EMIM][BF4] and TEG and [EMIM][BF4]+H2O was completed, and the experimental results well proved the reliability of the UNIFAC-Lei model. The unknown interaction parameters were obtained through the solubility data of this work and the experimental data in the literatures. The methyl chloride drying experiment was completed in the laboratory, and the water content of the methyl chloride can be reduced to below 200 ppm. The simulation of the methyl chloride drying process using [EMIM][BF4] or TEG as absorbents was carried out by ASPEN software on an industrial scale. The final simulation results show that the [EMIM][BF4] drying process has lower energy consumption and better drying effect.

The ionic liquid (IL) 1-ethyl-3-methylimidazolium dicyanamide ([EMIM][DCA]) was selected as an appropriate entrainer for the extractive distillation of the methanol–ethanol-water mixture. The COSMO-RS model was applied to screen out the appropriate solvents considering selectivity and solvent capacity together. Isobaric vapor–liquid equilibrium (VLE) experiments for the two systems of methanol–water and ethanol–water with different amounts of [EMIM][DCA] added were conducted at 101.3 kPa. The experimental data showed that [EMIM][DCA] exhibits an obvious salting effect for the methanol (or ethanol)-water mixture and eliminates the azeotropic point of ethanol–water. Moreover, the predicted values by UNIFAC-Lei model coincide well with experimental data. The separation mechanism was further explained in combination with surface charge density distribution (σ-profiles), excess enthalpy (HE), and binding energy. In addition, the flow charts were designed to evaluate the improvement of energy consumption with [EMIM][DCA] as the entrainer when compared to ethylene glycol (EG). The simulation results demonstrated that [EMIM][DCA] is more energy efficient than EG.