During the production of titanium stabilized stainless steel, as titanium in steel has a tendency to reacting with SiO2 in mould fluxes to generate TiO2 into mould fluxes and mould powder can inevitably pick up Ti-bearing inclusions floating up from steel, TiO2 content in the molten mould fluxes gradually increases so that physiochemical properties of the fluxes change. To evaluate the effect of TiO2 increase in mould fluxes on the structure of the mould flux, the glassy slag system CaO-SiO2-CaF2-TiO2 for stainless steel casting fluxes was studied by combining Raman spectroscopy with 29 in tetrahedral coordination, which cannot change the degree of polymerization of the silicate network. A small amount of Ti enters into the silicate network as the role of network formation, which slightly enhances the degree of polymerization of the silicate network. According to 19 F MAS-NMR spectra, most of the fluorine is exclusively coordinated by Ca 2+ corresponding to F-Ca(n) site and only a few Si-F bonds were observed in samples. Increase of TiO2 content has no significant effects on the F-bonds.

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Biomimetic giant membrane vesicles, with size and lipid compositions comparable to cells, have been recognized as an attractive experimental alternative to living systems. Due to the similarity of their membrane structure to that of body cells, cell-derived giant plasma membrane vesicles have been used as a membrane model for studying lipid/protein behavior of plasma membranes. However, further application of biomimetic giant membrane vesicles has been hampered by the side-effects of chemical vesiculants and the utilization of osmotic buffer. We herein develop a facile strategy to derive giant membrane vesicles (GMVs) from mammalian cells in biofriendly medium with high yields. These GMVs preserve membrane properties and adaptability for surface modification and encapsulation of exogenous molecules, which would facilitate their potential biological applications. Moreover, by loading GMVs with therapeutic drugs, GMVs could be employed for drug transport to tumor cells, which represents another step forward in the biomedical application of giant membrane vesicles. This study highlights biocompatible GMVs with biomimicking membrane surface properties and adaptability as an ideal platform for drug delivery strategies with potential clinical applications.

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Crystallization behaviors of new developed CaO-Al2O3 based mould fluxes with TiO2 addition for casting of high-Al steels were investigated by using DTA techniques combined with SEM-EDS and XRD analysis. XRD and SEM analyzed on the crystallized samples showed that the sequence of crystal precipitation for TiO2-free mould flux during cooling was MgO, and followed by Ca12Al14O33 during cooling. The sequence of crystal formation for TiO2-bearing mould fluxes during cooling is CaTiO3 to MgO, and then Ca12Al14O33. Continuous cooling transformation diagrams (CCT) were constructed for analysis of the crystallization behaviors. The Undercooling values for onset crystallization of various crystals were calculated by using liquidus temperature obtained by heating DTA and crystallization temperature of various crystals. The crystallization temperatures of CaO-Al2O3 based mould fluxes increased with increasing TiO2 content. The undercooling values for onset crystallization of CaTiO3 decreased with increasing TiO2 content, which indicating that the crystallization of CaTiO3 was enhanced with increasing TiO2 content. The undercooling values for onset crystallizations of Ca12Al14O33 and MgO only changed slightly with increasing TiO2. This indicated that crystallizations of Ca12Al14O33 and MgO crystals were only slightly influenced by TiO2 addition. The overall crystallization of mould fluxes was enhanced with increasing TiO2 content.

Fluorine-free mold flux has received ever increasing attentions due to environmental problems cause by fluorine in casting. Fluorine-free mold fluxes based on CaO-Al 2 O 3 -B 2 O 3 systems are developed in the present work. The melting temperatures, viscosities, and crystallization behaviors of CaO-Al 2 O 3 -B 2 O 3 based mold fluxes are investigated. The results show that the melting temperatures decrease with the increasing B 2 O 3 and Na 2 O content, while the melting temperatures of mold fluxes first increase with increasing CaO/Al 2 O 3 mass ratios, and then decrease with further increasing CaO/Al 2 O 3 ratios. The viscosity values of mold fluxes decrease with increasing of B 2 O 3 , Na 2 O content, and CaO/ Al 2 O 3 ratio. The crystallization temperatures of mold fluxes decrease with the increasing B 2 O 3 and Na 2 O, while the crystallization temperature of mold fluxes first increases with increasing CaO/Al 2 O 3 mass ratios, and then decreases with further increasing CaO/Al 2 O 3 ratios. XRD and SEM are used to analyze the sequence of crystallization. Ca 3 Al 2 O 6 crystals are precipitated at first, followed by LiAlO 2 during continuous cooling for all samples, and Ca 3 B 2 O 6 is precipitated finally. It is shown that CaO-Al 2 O 3 -B 2 O 3 based mold flux has a potential to be applied as a kind of F-free mold flux.