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The high manufacturing cost for metallic glasses hampers actual commercial applications of this class of fascinating materials. In this letter, the effect of oxygen impurity on the glass forming ability and tensile properties of Zr-BMG composites were studied. Our results have demonstrated that oxygen was absorbed and concentrated only in the precipitated β-Zr phase, leading that the remainder molten metal retains good glass forming ability. The high oxygen concentration in the β-Zr phase induces a significant solid-solution strengthening effect, this resulting in an enhanced strength of the BMG composites without sacrificing their overall ductility. Based on this alloying strategy, we have successfully developed the low-cost Zr-based BMG composites with excellent tensile properties and good glass forming ability, using the low grade industrial raw materials processed under industrial vacuum systems. This finding is expected to greatly cut down the manufacturing cost and greatly promote the commercial applications of the BMG composites.

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The performances of nanothermites largely rely on a meticulous design of nanoarchitectures and the close assembly of components. Three-dimensionally ordered macroporous (3DOM) NiO/Al nanothermite film has been successfully fabricated by integrating colloidal crystal template (CCT) method and controllable magnetron sputtering. The as-prepared NiO/Al film shows uniform structure and homogeneous dispersity, with greatly improved interfacial contact between fuel and oxidizer at the nanoscale. The total heat output of 3DOM NiO/Al nanothermite has reached 2461.27 J·g −1 at optimal deposition time of 20 min, which is significantly more than the values of other NiO/Al structural systems that have been reported before. Intrinsic reduced ignition temperature (onset temperature) and less gas production render the wide applications of 3DOM NiO/Al nanothermite. Moreover, 2 this design strategy can also be readily generalized to realize diverse 3DOM structured nanothermites.

In this paper, a simple high performance liquid chromatography (HPLC) method for the determination of colistimethate sodium in the productions of synthesis from colistin E sulphate was established. A HPLC gradient which was: 20% B+80% A changed to 50% B+50% A in 10 min (A was 0.05% TFA aqueous solution and B was acetonitrile) was used and the separation was realized in 8 minutes. Moreover, this method was also used in the separation of colistin sulphate with good resolution. Compared to the methods reported previously, the present method was finished easier in a much shorter time which is 6 min. LC-MS was used to detect colistin sulphate and the result showed that the two compositions were colistin sulphate E1 and E2 as expected. Good separation and reproducibility were obtained.

Polymerizable phenolphthalein derivatives with pH-sensitive properties were synthesized in the course of electrophilic aromatic substitution reactions. 4) were obtained and characterized. Copolymerization of 3 and 4 with acrylic acid (5a), N-(isopropyl)acrylamide (5b), and N,N-dimethylacrylamide (5c) enabled the synthesis of color switchable materials. Thereby, water-soluble pH sensitive linear polymers 6 and 7 were prepared using monomer 3. Additionally, cross-linked polymers 8 were prepared successfully by copolymerization of 4 and 5c. These pH-sensitive polymers form hydrogels in aqueous solution. Linear viscoelastic behavior depending on the concentration of the cross-linker was observed.