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The influence of H 2 SO 4 solution concentration on the corrosion behavior of as-cast Al 0.1 CoCrFeNi high-entropy alloys (HEAs) is investigated. The potentiodynamic polarization curves of the Al 0.1 CoCrFeNi HEA exhibit excellent corrosion resistance and a wide passive region (ΔE > 1150 mV) in acid solutions. The samples show a spontaneous passivation behavior in low-concentration (0.1, 0.2 and 0.3 M) and two anodic active–passive peaks in high-concentration (0.5 and 1.0 M) H 2 SO 4 solutions. The morphology investigation by scanning electron microscopy suggests that selective corrosion is initiated from the inter-dendrite regions. The X-ray photoelectron spectroscopy results demonstrate that the observed passive behavior variation is associated with chemical composition change of the passive films. • Effect of acid concentration on Al 0.1 CoCrFeNi HEA corrosion behavior was studied. • The Al 0.1 CoCrFeNi HEA exhibits an extensive passive region in acidic solutions. • Element contents differ in the passivation films formed under different potentials. [ABSTRACT FROM AUTHOR]

Abstract SSZ-13 zeolite with a SiO 2 /Al 2 O 3 ratio in the range of 26–183 was synthesized by adding zeolite L in the synthesis gel absent from additional aluminum source, and the effects of SiO 2 /Al 2 O 3 and N,N,N-trimethyladamantammonium hydroxide (TMAdaOH)/SiO 2 ratios on the crystallization were investigated. The crystallization mechanism was studied with X-ray diffraction, Scanning electron microscopy, Fourier transform infrared spectroscopy and 29Si and 27Al MAS NMR spectroscopy techniques. It is shown that the SiO 2 /Al 2 O 3 and TMAdaOH/SiO 2 ratios have a significant effect on the acidity, and thus, the methanol-to-olefins (MTO) performance of SSZ-13. The co-presence of TMAdaOH, NaOH and extra silica source (SiO 2) is necessary for formation of SSZ-13. The crystallization of SSZ-13 occurs by decomposing structure of zeolite L into double six- and four-membered rings that subsequently restructure into CHA topology under the direction of TMAdaOH, and further induce the nucleation and crystal growth. It is noteworthy that the Al species in zeolite L directly transform into those of SSZ-13 without forming monomeric species. The prepared SSZ-13 shows higher catalytic stability and selectivity to ethylene and proplyene than the conventionally synthesized sample from amorphous aluminosilicate gel in MTO reaction. Graphical abstract Image 1 Highlights • LTL hydrothermal conversion into high silica CHA was performed with the TMAdaOH. • The product SSZ-13 zeolite was strongly affected by starting Si/Al and SDA/Si ratio. • The crystallization rate of SSZ-13 from L-added starting gel was distinctly enhanced. • The crystallization mechanism of SSZ-13 from L-added starting gel was discussed. • The obtained SSZ-13 from L-added gel showed enhanced catalysis for MTO reaction. [ABSTRACT FROM AUTHOR]

In this work, we systematically investigated mechanical behaviors and deformation mechanisms of MP159 superalloy over wide strain rate range (10−4/s – 103/s). The results show that when the strain rate increases from 10−4/s to 1500/s, the yield strength of the current alloy is increased from ∼850 MPa to ∼1155 MPa, and the elongation remains around 30 %, exhibiting an extraordinary strength-ductility synergy and remarkable strain-hardening capacity. Furthermore, the plastic deformation mechanism performs a transition from stacking faults (SFs) at low strain rates to a large number of twinning at high strain rates. The MP159 alloy exhibited excellent mechanical properties at high strain rates, which stem from the nanotwins and twin-SF interactions. This study reveals the plastic deformation mechanisms of MP159 superalloy under dynamic loading, providing feasible suggestions for the selection and design of structural materials in extreme environments. • The MP159 superalloy possesses superior synergistic behaviors over wide strain rate range (10−4/s – 103/s). • Multiple strengthening mechanisms facilitate extraordinary strain-hardening capacity. • The contribution of the separation strengthening is 449 MPa caused by the fine and dispersed L1 2 particles in the matrix. • Stacking fault energy is approximately calculated as 21.63 mJ/m2 from thermodynamic. [ABSTRACT FROM AUTHOR]

Highly-stable aqueous dispersion of (NH 4 ) x WO 3 crystallites (ac. 6–12 nm in diameter and 20–100 nm in length) with decent infrared shielding ability was synthesized at only 100 °C. The effects of reducing agent (N 2 H 4 ∙2HCl) dosage on the phase, morphology, zeta potential and composite of products have been systematically addressed. It was shown that the addition of N 2 H 4 ∙2HCl in precursor solution introduced obvious oxygen deficiency into (NH 4 ) x WO 3 crystallites, resulting in a further improved NIR shielding ability. However, high dosages of N 2 H 4 ∙2HCl were found to depress the zeta potentials and accelerate the growth of (NH 4 ) x WO 3 crystallites. A mechanism, which was reasonably supported by confirmatory experiments, was extracted to explain the result. To show potential application of our product, (NH 4 ) x WO 3 -based flexible solar control foils were prepared by directly casting the dispersion onto polyethylene terephthalate (PET) substrates. The foils can selectively cut-off near infrared light (NIR) by 65.8% (transmittance depressed from 91.3% of a bare PET to 25.5% of the foils), while maintaining a high visible transmittance of 67.6%, showing promise as energy-efficient filter. [ABSTRACT FROM AUTHOR]