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The microstructure, electrochemical corrosion behaviour and microhardness of Fe1.5CoNiCrCux (x = 0.5, 1.0, 1.5 and 2.0) high-entropy alloys (HEAs) were investigated by X-ray diffraction (XRD), scanning electron microscopy and an electrochemical workstation. The XRD spectra of Fe1.5CoNiCrCux HEAs confirmed the face-centred cubic solid solution structure and that all specimens consisted of an fcc matrix and a Cu-rich fcc phase. The results of electrochemical corrosion tests showed that Fe1.5CoNiCrCu0.5 HEAs exhibited low corrosion rates owing to their high corrosion potential and low corrosion current density. The major types of corrosion for Fe1.5CoNiCrCux HEAs belong to localised corrosion and pitting, which is attributed to Cu-rich and Cr-depleted phases in the interdendritic region. The microhardness of Fe1.5CoNiCrCux HEAs increases from 142 HV for alloys with x = 0.5 to 190 HV for alloys with x = 2.0.

The salt corrosion environment has direct degradation to durability of asphalt mixture and dynamic water also has an important influence on asphalt pavement performance. In order to evaluate the performance of asphalt mixture exposed to dynamic water and chlorine salt erosion, the asphalt mixture dynamic water-salt erosion apparatus was self-designed and the test parameters were reasonably set for the accelerated simulation of chlorine salt-water-temperature-load coupling action to asphalt mixture under real working conditions. Splitting test (25 °C and −10 °C) was adopted for assessing the performance of asphalt mixture suffered from chlorine salt-water-temperature-load coupling action. Then the grey entropy method was applied to analyze the significance of influencing factors on the performance of asphalt mixture such as dynamic water scouring times, temperature, salt solution concentration. Then the mechanism of performance deterioration of asphalt mixture was explored to some extent. The results show that the process of chlorine salt erosion and deterioration to asphalt mixture is accelerated by dynamic water and is closely related to the concentration and temperature of salt solution. Scouring times is the most significant factor influencing the performance of asphalt mixture exposed to dynamic water and chlorine salt erosion. The crystallization erosion caused by salt solution infiltrating into the voids and cracks of asphalt mixture is an important inducement for the performance deterioration.

As a typical hole-doped cuprate superconductor, Bi 2 Sr 2 CaCu 2 O 8+{\delta} (Bi2212) carrier doping is mostly determined by its oxygen content. Traditional doping methods can regulate its doping level within the range of hole doping. Here we report the first application of CaH 2 annealing method in regulating the doping level of Bi2212. By continuously controlling the anneal time, a series of differently doped samples can be obtained. The combined experimental results of x-ray diffraction, scanning transmission electron microscopy, resistance and Hall measurements demonstrate that the CaH 2 induced topochemical reaction can effectively change the oxygen content of Bi2212 within a very wide range, even switching from hole doping to electron doping. We also found evidence of a low-T c superconducting phase in the electron doping side., Comment: 7pages,3 figures and Supplementary Material 3pages,3 figures

This article presents a study evaluating the adhesion properties between asphalt and calcined bauxite. Limestone and granite were also compared with calcined bauxite. For this purpose, asph...

Bismuth (Bi) has been known as a highly efficient electrocatalyst for CO2 reduction reaction. Stable free-standing two-dimensional Bi monolayer (Bismuthene) structures have been predicted theoretically, but never realized experimentally. Here, we show the first simple large-scale synthesis of free-standing Bismuthene, to our knowledge, and demonstrate its high electrocatalytic efficiency for formate (HCOO−) formation from CO2 reduction reaction. The catalytic performance is evident by the high Faradaic efficiency (99% at −580 mV vs. Reversible Hydrogen Electrode (RHE)), small onset overpotential (, Stable free-standing two-dimensional Bi monolayer (Bismuthene) structures have been predicted theoretically, but never realized experimentally. Here, the authors show a large-scale synthesis of free-standing Bismuthene and its electrocatalytic activity for CO2 reduction to formate.

In order to effectively solve the traffic safety problem caused by snow and ice covering the pavement in winter, steel wool fibers with different length and content were adopted in asphalt mixture to investigate its deicing performance. The deicing principle of steel wool fiber asphalt mixture by induction heating was expounded. Effects of different ice thicknesses, output currents, and ambient temperatures for asphalt mixture deicing performance were studied using an indoor-simulated induction heating deicing test. The deicing mechanism of steel wool fiber asphalt mixture by induction heating was analyzed. Grey relation entropy analysis between the average melting ice rate and the influencing factors was determined. The results show that the average ice melting rate of the asphalt mixture increases with the increase in steel wool fiber length and content. The steel wool fiber asphalt mixture heated by electromagnetic induction obtains satisfactory result. The average melting ice rate of asphalt mixture containing 6% steel wool fiber with a length of 3 mm can reach 0.50°C·s−1 at an ambient temperature of −5°C. The thinner the ice and the higher the ambient temperature, the higher the average melting ice rate. The output current is positively correlated with the average melting ice rate. The degree of influence of the five influence factors on the average melting ice rate is ranked in order as follows: fiber content, fiber length, output current, ambient temperature, and ice layer thickness.

The electrochemical reduction reaction of carbon dioxide (CO2RR) to carbon monoxide (CO) is the basis for the further synthesis of more complex carbon-based fuels or attractive feedstock. Single-atom catalysts have unique electronic and geometric structures with respect to their bulk counterparts, thus exhibiting unexpected catalytic activities. A nitrogen-anchored Zn single-atom catalyst is presented for CO formation from CO2RR with high catalytic activity (onset overpotential down to 24 mV), high selectivity (Faradaic efficiency for CO (FECO ) up to 95 % at -0.43 V), remarkable durability (>75 h without decay of FECO ), and large turnover frequency (TOF, up to 9969 h-1 ). Further experimental and DFT results indicate that the four-nitrogen-anchored Zn single atom (Zn-N4 ) is the main active site for CO2RR with low free energy barrier for the formation of *COOH as the rate-limiting step.

Differential scanning calorimetry (DSC) was used to investigate the thermal behavior and non-isothermal crystallization kinetics of the Fe67Nb5B28 metallic glasses prepared by melt-spinning method. DSC traces exhibit that the crystallization takes place through a single exothermic reaction, and it processes a good thermal stability in thermodynamics. The activation energies for nucleation and grain growth processes were calculated to be 536 ± 22 and 559 ± 20 kJ mol−1 by Kissinger equation, respectively, and 551 ± 24 and 574 ± 20 kJ mol−1 by Ozawa equation, respectively. It means that the grain growth process is more difficult than the nucleation process. The variation of local Avrami exponent n(x) with crystallized fraction x demonstrates that the crystallization mechanism varies at different stages. The n(x) is larger than 2.5 at the initial stage of 0