Search

The de‐acidification method has always been a hotspot in the research of paper‐based cultural relics conservation science. The existing de‐acidification methods are either not thorough enough or not easy to operate, requiring innovation and breakthrough. Moreover, the strength of the paper cannot be significantly improved by the simple de‐acidification treatment. To achieve the reinforcement of paper, another intervention process is often required, and each intervention may cause damage to the fragile paper cultural relics. This study introduces electrosorption deionization technology to the conservation treatment of paper cultural relics. Based on the electrosorption technology, an integrated treatment of paper de‐acidification and reinforcement was applied to sample papers using a composite electrolyte of de‐acidification and reinforcement materials and a self‐made electrosorption device. The experimental results show that both the de‐acidification and reinforcement effects on the paper samples obtained a significant promotion. [ABSTRACT FROM AUTHOR]

Recently, 2D Mo2C, a new member of the MXene family, has attracted much attention due to the exotic superconducting properties discovered in 2D α-Mo2C. Here, not only 2D α-Mo2C but also 2D β-Mo2C crystal sheets with distinct disordered carbon distributions were successfully grown. 2D β-Mo2C shows a much stronger superconductivity than 2D α-Mo2C, and their superconductivities have different hydrostatic pressure responses. The superconducting transition temperature Tc of 2D α-Mo2C shows a dome-shaped profile under pressure, implying the existence of two competing effects arising from phononic and electronic properties, while for 2D β-Mo2C, Tc decreases monotonically with increasing pressure, possibly due to phonon stiffening. These results indicate that the electronic properties have a more important influence on the superconductivity in 2D α-Mo2C compared to 2D β-Mo2C. The ordered and disordered carbon distributions in 2D α-Mo2C and β-Mo2C, respectively, may be the underlying origin for their different electronic and superconducting properties. It is still a mystery whether disorders could be beneficial for the superconductivity or not. In this work, it is surprising to find out that the carbon disordered 2D β-Mo2C crystal sheet shows a much stronger superconductivity than the carbon ordered 2D α-Mo2C crystal sheet, and the in-situ order-disorder transition from α-Mo2C to β-Mo2C induced by e-beam irradiation results in an enhanced superconductivity. Especially, the Tc variation trends of α-Mo2C and β-Mo2C are different under hydrostatic pressures. These results highlight the important role of disorders in the superconducting properties owing to the carbon distributions in Mo2C. Superconductors: 2D nanomaterials thrive under pressure and e-beam irradiation Two-dimensional (2D) molybdenum carbide (Mo2C) sheets, an ultrathin crystal system, have attracted much attention due to the exotic superconducting properties. Now, Li's group from the University of Science and Technology of China in Hefei and colleagues report that 2D Mo2C can be synthesized into two crystal forms that exhibit distinctly different superconducting behaviors when compressed in a pressure cell. The team demonstrated that the disordered 'beta' crystal phase of Mo2C becomes superconductive at higher temperatures than the more ordered 'alpha' form. The in-situ order-disorder transition from 'alpha' to 'beta' Mo2C induced by e-beam irradiation results in an enhanced superconductivity. Additionally, the superconductivities of the two forms of 2D crystals showed different responses to thickness changes. These experiments suggest that the positioning of carbon atoms plays a crucial role in the superconductivity in related 2D crystals. [ABSTRACT FROM AUTHOR]

The laser-induced transverse voltage (LITV) was investigated systematically in (111)-oriented cubic TiO1+δ (1.08 ≤ 1 + δ ≤ 1.28) thin films grown on nontilted (0001)-oriented α-Al2O3 substrates. Utilizing the anisotropy between [001] and [110] directions, a feasible LITV measuring configuration was designed, and the peak voltage Up at room temperature reaches 0.92 V for the sample TiO1.08 irradiated by a laser with a wavelength of ∼248 nm and an energy density of ∼10 mJ/cm2. Both the voltage amplitude and the sensitivity of LITV decrease with the increasing oxygen content, probably due to the enhancement of disorder strength and the reduction of density of electronic states near the Fermi level. The Up value of the TiO1.08 film rises to 1.22 V upon increasing temperature to 450 K and then decreases upon further increasing the temperature. The LITV variations at different wavelengths indicate that the LITV should mainly come from a transverse thermoelectric effect when the photon energy is lower than the bandgap but may contain a contribution from a transverse photovoltaic effect when the photon energy is larger than the bandgap. These results provide considerable insight into LITV and offer a feasible method to explore more LITV materials. [ABSTRACT FROM AUTHOR]