In orthopedics, developing functionalized biomaterials to enhance osteogenesis and bacterial resistance is crucial. Although poly­(ether ether ketone) (PEEK) is regarded as an important engineering plastic for biomedical material with excellent mechanical properties and biocompatibility, its biological inertness has greatly compromised its application in biomedical engineering. Inspired by the catecholamine chemistry of mussels, we propose a universal and versatile approach for enhancing the osteogenesis and antibacterial performances of PEEK based on surface functionalization of polydopamine-modified nanohydroxyapatite and lysozyme simultaneously. The characterizations of surface morphology and elemental composition revealed that the composite coating was successfully added to the PEEK surface. Additionally, the in vitro cell experiment and biomineralization assay indicated that the composite coating-modified PEEK was biocompatible with significantly improved bioactivity to promote osteogenesis and biomineralization compared with the untreated PEEK. Furthermore, the antibacterial test demonstrated that the composite coating had a strongly destructive effect on two bacteria (Staphylococcus aureus and Escherichia coli) with antibacterial ratios of 98.7% and 96.1%, respectively. In summary, the bioinspired method for surface functionalization can enhance the osteogenesis and bacterial resistance of biomedical materials, which may represent a potential approach for designing functionalized implants in orthopedics.

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The influence of different reactivity coke on reduction, softening, melting and dropping properties of iron-bearing burden were studied by melting and dropping experiment, meanwhile reduction mechanism and softening-melting mechanism of stock column, as well as stock column pressure difference were also analyzed. The results show that reduction degree at 1 000°C increases, softening-melting start temperature and dropping temperature decrease, and melting temperature rises, when the coke reactivity increases from 24.76% to 56.28%. Softening and melting temperature interval increases, melting and dropping temperature interval reduces and stock column permeability is improved as the coke reactivity increased, which lead to softening-melting and dropping properties value of iron-bearing burden reducing. In addition, industrial experimental analysis shows that reducing agent rate (RAR) can be reduced by 8.26 kg/t using high reactivity coke (HRC) of 12%. Therefore, the appropriate increase of coke reactivity could improve stock column permeability and high temperature properties of iron-bearing burden, so as to reduce RAR.

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The influences of the different reactivity cokes on softening-melting dropping of iron-bearing burden were studied by melting-dropping experiment. The pressure difference and shrinkage rate of burden layer, as well as the burden reduction degree at the same temperature were also analyzed. The results show that the softening and melting starting temperature reduces from 1200 to 1160 8C, and the softening and melting end temperature increases from 1290 to 1320 8C, while the melting ending temperature is unchanged and the dropping temperature of molten iron reduces from 1413 to 1380 8C, when the coke reactivity increases from 24.76 to 65.16%. Softening-melting temperature interval increases with the improvement of coke reactivity based on the above temperatures change, meanwhile, melting temperature interval and the dropping temperature interval (DT 3 ¼ T d À T P ) reduces, respectively. In addition, the shrinkage rate of charge column decreases and the permeability of charge column get better when the coke reactivity increases from 24.76 to 65.16%. The softening-melting and dropping characteristic evaluation of iron-bearing burden reduces with the improvement of coke reactivity. Appropriately increasing coke reactivity may improve charge column permeability and increase softening-melting and dropping characteristic of iron-bearing burden, therefore, it is of great significance for saving energy and reducing consumption of blast furnace smelting.

Based on the analysis of the existing evaluation methods and with the combination of the characteristic of cohesive zone characteristic in blast furnace (BF) and softening–melting and dropping experimental result of iron bearing burden, a new evaluation method of softening–melting and dropping characteristic of iron bearing burden was put forward, which can be used for evaluating various kinds of iron bearing burden. The softening–melting and dropping characteristics of the mixed burden and the high metalized burden are evaluated through the new method, which verified that the new method is reasonable and feasible. The results showed that the new method can judge not only the corresponding relation between the shrinking percentage and the unit charge column pressure drop, but also the influence of softening and melting temperature interval, melting temperature interval and dropping temperature interval on the softening–melting and dropping characteristic value of iron bearing burden. This new method is expected to provide technical guidance for BF smelting.

Based on the thermodynamic parameters and experimental diffusion data in the literature, the atomic mobilities of bcc Ti-Sn alloys are assessed by the CALPHAD method using DICTRA software package, and boundary mobility parameters of hcp Ti-Sn alloys were also given in the work. Compared with the calculated and measured diffusion coefficients of bcc Ti-Sn, most of the experimental data are reproduced well. The composition-distance profiles of Ti/Ti-4.9 at.% Sn diffusion couple at 1223 K for 14.4 ks were also predicted using the assessed mobility parameters. It is hopeful to provide useful guidance for the design of Ti-based alloys.

In this work, a Ti -pillared montmorillonite with high thermal stability has been prepared by using a Na -montmorillonite as the host clay and polyhydroxy-titania ions as the pillaring precursor. The formation of Ti -pillared montmorillonite has been confirmed from the characterizations through X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric–differential scanning calorimeter, and specific surface area analyses. In the preparation of Ti -pillared montmorillonite several parameters, such as the type of solvent in which the synthesis is realized, the ratio of polyhydroxy-titania ions and montmorillonite, the intercalation time, the calcining temperature, and calcining time, were tested to understand their effects on the basal spacing. It was shown that this method could produce a Ti -pillared montmorillonite with the basal spacing of 3.74 nm, specific surface area of 409 m2/g, and mean pore size of 2.94 nm, as well as a high thermal stability up to 900°C.