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By a combination of the nanoindentation and electron probe microanalysis (EPMA) techniques, the traditional diffusion couple technique is extended to map the mechanical property of β-type Ti alloys over a wide composition range, which can be utilized to develop very versatile novel bio-Ti alloys for hard tissue replacements in artificial bones, joints, and dental implants. To create complete single-phase composition ranges of Ti-based bcc solid solution, 12 types of bcc Ti–Nb–Zr–Mo/Ti–Nb–Zr–Ta quaternary diffusion couples were fabricated and annealed at 1273 K for 25 h. In this way, the composition-mechanical property relationships in the vast composition space of Ti-based alloys were established using EPMA and nanoindentation probes. Notably, the measured composition-dependent Young's moduli, hardness, and elastic recovery as well as the derived ratio of hardness to Young's modulus, and the ratio of the cube of hardness to the square of Young's modulus, in the developed compositional mechanical property database, were visualized in a five-dimensional scatter plot. This enables an effective tool to screen the Ti–Nb–Zr-based alloys for orthopedic and dental applications according to different clinical requirements, and to rationalize the fundamental mechanical relationships in the rapid development of β-Ti alloys.

The effects of bisulfite-activated permanganate technology (PM/BS) as a pre-oxidation process on enhancing Microcystis aeruginosa (M. aeruginosa) removal by post coagulation were investigated. The results demonstrated that pretreatment with PM/BS process effectively promoted the algae removal by coagulation with Al2(SO4)3 as the coagulant and this phenomenon was more obvious with the increase of water hardness. Compared to the sole coagulation, PM/BS pre-oxidation combing with coagulation could neutralize the zeta potential of algal cells effectively, decrease the algal cell size, and lead to the formation of more compact flocs due to the in-situ generated MnO2. The effect of oxidant dosages on algal organic matter (AOM) was also studied and no obvious release of macromolecular substances was observed with the dosage of KMnO4 increasing from 3.0 mg/L to 7.0 mg/L, suggesting the integrity of algal cells at a high KMnO4 dosage. Moreover, PM/BS pre-oxidation could lead to the decrease of most analyzed disinfection by-products (DBPs) at a Al2(SO4)3 dosage of 40.0 mg/L. The algae removal efficiency was also significantly enhanced by PM/BS pre-oxidation in the test using real algae-laden water. This study indicated that PM/BS process might be a potential assistant technology for algae removal by subsequent coagulation.

The degradation of Orange II (Org II) by ferrous activated peroxymonosulfate (PMS) was inspected. The maximum degradation efficiency of 62.3% in 90 min occurred at 0.286 mM [PMS]0, corresponding to 1:1 molar ratio of Fe2+: PMS. Results show that poor recovery of Fe2+ accounts for poor degradation in the slow stage. The species of reactive radicals were determined through indirect way by quenching agents, as well as directly by in situ EPR spin trapping tests. Results indicated that hydroxyl radicals instead of sulfate radicals were responsible for Org II degradation. The removal of Org II degradation would increase to 93.3% in 90 min as reaction temperature increased to 60 °C. The activation energy for PMS and Fe2+/PMS alone was calculated to be 77.2 kJ/mol and 34.7 kJ/mol, respectively. The removal efficiency of total organic carbon (TOC) was 11.0% and 43.8% when [Fe2+]0:[PMS]0:[Org II]0 was 5:5:1 and 34:34:1, respectively. The main degradation products of Org II in system were supposed to be heterocyclic compounds containing a five-atom ring. Results demonstrated that Fe2+/PMS technology is promising technology for water pollution.

Young's modulus is essential for the design and production of the alloys. Thus, we proposed a MGI (Materials Genome Initiative)-oriented strategy for the high-throughput development of Young's modulus databank in the single-phase alloys. In this study, 17 diffusion couples of the bcc Ti-rich Ti–Nb–Zr, Ti–Nb–Cr and Ti–Nb–Zr–Cr systems annealed at 1273 K for 25 h were experimentally prepared. Subsequently, the composition-dependent Young's moduli and hardness in the bcc Ti-rich Ti–Nb–Zr–Cr system were determined by combining the nanoindentation technique and the electron probe micro analysis (EPMA). Moreover, on the basis of the presently obtained experimental data, the Young's modulus databank in the bcc Ti–Nb–Zr–Cr system were established by means of the CALPHAD (CALculation of PHAse Diagrams) approach. Finally, the Ti–22.6 at.% Nb–30 at.% Zr–3.8 at.% Cr alloy was designed from the Young's modulus databank and verified by using the nanoindentation and cytotoxicity tests. The results reveal that the present MGI-oriented strategy with the combination of the high-throughput measurements and the CALPHAD approach is a very effective method to accelerate the design/development of novel bio-Ti alloys.

Recently, sulfidation of zerovalent iron (ZVI) has gained increasing attention due to its merits to enhance both the reactivity and electron efficiency (EE) of ZVI. While few studies have been conducted to elucidate the influence of coexisting ions on EE of sulfidated ZVI, which is important for up-scaling such a decontamination strategy. In this study, taking Se(VI) as a probe, the influence of coexisting ions, including Cl−, SO42−, PO43−, Ca2+, and Mg2+, on the removal capacity and EE of ZVI under aerobic conditions was investigated. Results revealed that, compared to unamended ZVI, sulfidated ZVI synthesized by ball-milling with elemental sulfur (S-ZVIbm) could enhance EE of ZVI toward Se(VI). However, this enhancing effect is not very effective and the maximum of EE value obtained in this work is only 8.8%. Chloride with concentration range of 1–20 mM was found to exert little influence on EE of ZVI. While for SO42− and PO43−, relative to 10 mM NaCl, their presence could depress EE of S-ZVIbm, and this inhibiting effect became more pronounced as their concentration elevated. In contrast, Ca2+ or Mg2+ hardness ions (0.05–2 mM) increased the EE values of S-ZVIbm by 19.2–83.3%. X-ray absorption fine structure analysis revealed that all of Fe0 in S-ZVIbm was exhausted within 24 h with lepidocrocite and magnetite being the primary corrosion products. This suggested that it was the amounts of electrons accepted by Se(VI) rather than that donated by S-ZVIbm accounted for the variation of EE. In general, these co-solutes may impose their influence on EE through affecting Se(VI) adsorption and the subsequent electron transfer from Fe0 core to Se(VI) at the water-particle interface.