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• A multifunctional coating was constructed on ZE21B alloy for biodegradable vascular stents. • MgF 2 layer and hydrophilic polymers in the functional coating could effectively protect ZE21B alloy from overfast degradation. • Anticoagulant ACH 11 peptides and ECs-selective REDV peptides in the functional coating could dramatically enhance the hemocompatibility and pro-endothelialization capacity of ZE21B alloy. • The functional coating systematically improved the corrosion resistance and biocompatibility of ZE21B alloy in vitro and in vivo. Biodegradable magnesium alloy stents (MAS) have great potential in the treatment of cardiovascular diseases. However, too fast degradation and the poor biocompatibility are still two key problems for the clinical utility of MAS. In the present work, a functional coating composed of hydrophilic polymers and bioactive peptides was constructed on magnesium alloy to improve its corrosion resistance and biocompatibility in vitro and in vivo. Mg-Zn-Y-Nd (ZE21B) alloy modified with the functional coating exhibited moderate surface hydrophilicity and enhanced corrosion resistance. The favourable hemocompatibility of ZE21B alloy with the functional coating was confirmed by the in vitro blood experiments. Moreover, the modified ZE21B alloy could selectively promote the adhesion, proliferation, and migration of endothelial cells (ECs), but suppress these behaviors of smooth muscle cells (SMCs). Furthermore, the modified ZE21B alloy wires could alleviate intimal hyperplasia, enhance corrosion resistance and re-endothelialization in vivo transplantation experiment. These results collectively demonstrated that the functional coating improved the corrosion resistance and biocompatibility of ZE21B alloy. This functional coating provides new insight into the design and development of novel biodegradable stents for biomedical engineering. [ABSTRACT FROM AUTHOR]

The rise in carbon emissions linked to the tourism industry has challenged its long-standing reputation as an eco-friendly sector. In parallel, the digital economy's evolution has introduced a series of transformations within tourism. This necessitates a thorough examination of the intricate interplay between the digital economy and carbon emissions in the tourism sector. With the help of Chinese provincial panel data, this study uncovers a compelling relationship marked by an inverted "U" curve through two-way fixed model, moderated effects model and threshold regression analysis. Intriguingly, an increase in road density shifts the inflection point of this curve to the lower left. As road density reaches a critical threshold of 0.361, it not only amplifies the elasticity of the inverted "U" curve but also accelerates the timeline to reach peak tourism-related carbon emissions. This study underscores a significant practical implication: while digital technology exacerbates carbon emissions from tourism at this stage, the dampening effect of digital technology is to be expected as the development of industrial manufacturing brings better transportation. However, the timing of the tipping point may be earlier or later for different regions, depending on whether the local level of industry is sufficiently developed. • The inverted "U" curve relationship between digital economy growth and tourism carbon emissions at the provincial level in China is validated. • Transportation accessibility is a key mechanism by which the digital economy affects carbon emissions from tourism. • This paper predicts the conditions for an inflection point in tourism carbon emissions within digital economy. [ABSTRACT FROM AUTHOR]

Hard nitride coatings have the prospect of acting as protective layers for cutting tools because of their excellent mechanical properties and wear resistance. To enhance the mechanical, tribological, and high-temperature oxidation properties, the structural design of the coating is important. In this study, TiSiN, CrAlN/TiSiN bilayer and CrAlN/TiSiN multilayer coatings were deposited on the surface of high-speed steel by multi-arc ion plating technology. The microstructure, phase composition, mechanical properties and high-temperature tribological properties of prepared coatings were analyzed. Results indicated that the TiSiN and CrAlN/TiSiN bilayer coatings contain TiN phases and the CrAlN/TiSiN multilayer coating contains three main phases of TiN, AlN and CrN. The CrAlN/TiSiN multilayer coating possesses a denser microstructure than the other two coatings. The multilayer structure improves the cohesive and bonding strength of the coating by reducing the shear stress. The CrAlN/TiSiN multilayer coating exhibits a stable coefficient of friction and excellent wear resistance during high-temperature friction. The formation of TiO2 and Al2O3 oxide layers on the surface of the coating in a high-temperature environment contributes to the desired tribological properties of the coatings. [ABSTRACT FROM AUTHOR]

Improving capacity utilization (CU) is a critical way for China to promote economic transformation and achieve sustainable development. As a market-based environmental regulation proposed to achieve a low-carbon economy and green transformation, whether emission trading system (ETS) can improve CU deserves an in-depth study. We conduct an empirical study by constructing a multi-period difference-in-differences model with 1,037 Chinese A-share listed firms from 2004 to 2020 as the research sample. The result shows that the ETS can significantly improve CU, which still holds after a series of robustness tests. The mechanism analysis shows that the ETS improves CU through three mechanisms: stimulating green innovation, restricting over-investment, and alleviating financing constraints. Based on the heterogeneity analysis, the improvement of CU by ETS is greater among listed firms in heavy-polluting industries, with good ESG performance, excess leverage, and central state ownership. Our study supports the global implementation of the ETS and provides ideas for resolving overcapacity in the context of global decarbonization. [ABSTRACT FROM AUTHOR]

[Display omitted] • The novel polyether materials were synthesized by cationic ring-opening controllable polymerization of 1,2-butylene oxide (BO) with tetrahydrofuran (THF). • The poly(1,2-butylene oxide- stat -tetrahydrofuran)s has a super high viscosity index (≥198) and low pour point (≤-53 °C), which can be used as a base oil and additives in the field of high-performance lubricants. Aliphatic polyethers are synthesized byring-opening polymerization (ROP) of the most common epoxide monomers, such as ethylene oxide (EO) and propylene oxide (PO). 1,2-Butylene oxide (BO) and tetrahydrofuran (THF) are potentially extended ROP monomers, which can give polyether unique properties. In this work, a series of poly(1,2-butylene oxide- stat -tetrahydrofuran)s (PBO- stat -PTHFs) with M n of 900–3700 g·mol−1 were synthesized by cationic ring-opening polymerization (CROP) of BO with THF using strong Lewis acid Rare Earth triflates (RE(OTf) 3) as catalysts and diols as an initiator at room temperature. PBO- stat -PTHFs product with yield up to 90 %, narrow polydispersity of Đ <1.30, and molar ratio of PBO to PTHF 1:1 were obtained. The copolymerization process was studied by in-situ IR and 1H NMR spectroscopy analysis, and the results showed that PBO- stat -PTHF is a statistical copolymer. The early stage of the polymerization reaction was dominated by the activated chain end mechanism (ACEM), which incorporates a large amount of THF into the polymer chains. However, the late stage of the polymerization reaction was dominated by the activated monomer mechanism (AMM), which incorporates a large amount of BO into the polymer chains. Most PBO- stat -PTHFs have a suitable M n range, super high viscosity index (≥198) and low pour point (≤-53 °C), which can be used as a lubricant base oil and additives. In addition, PBO- stat -PTHFs have excellent miscibility with polyalphaolefin (PAO), which could significantly improve the PAO viscosity index. This study provides a mild route to construct high-performance copolyether materials through cationic ring-opening controllable polymerization. [ABSTRACT FROM AUTHOR]

The effects of boron content on the glass-forming ability, mechanical and elastic properties in Co 92 − x B x Ta 8 (at.%, x = 30, 32.5, 35, and 37.5) bulk glassy alloys were investigated. Among these alloys studied, the Co 59.5 B 32.5 Ta 8 alloy exhibits the highest glass-forming ability, which could form a glassy rod at least 3 mm in diameter by the copper mold casting method. It is found that the plasticity of those glassy alloys increases with decreasing boron content. The plastic strains for the Co 59.5 B 32.5 Ta 8 and Co 62 B 30 Ta 8 BMGs are up to ∼2.1% and ∼2.5%, respectively. The decrease of shear modulus with decreasing boron content results in the increase of Poisson’s ratio, which is responsible for the improved plasticity. In addition, the strength of the ductile glassy alloys remains very high at above 5000 MPa, although enhancing plasticity is accompanied by the loss of some strength. The present results show that Co–B–Ta bulk metallic glass with good glass-forming ability and significant plasticity as well as ultrahigh strength can be synthesized by adjusting alloy composition. [ABSTRACT FROM AUTHOR]

Abstract: In order to solve the soot emission problems from diesel engines, a series of La2Sn1.8M0.2O7 (M= Sn, Mn, Fe, Co, Cu) oxides with pyrochlore structure were synthesized by co-precipitation, and investigated for soot oxidation with a O2/NO mixture by Temperature-programmed Oxidation. The incorporation of transition metals strongly influences the crystallite size, surface area and redox properties of the catalysts. All the pyrochlore oxides display catalytic soot oxidation activity with nearly 100% selectivity towards CO2. The doped pyrochlores exhibit higher activities than the undoped, which may be related to the enhancement of reducibility. Among them, La2Sn1.8Mn0.2O7 possessed the best activity with Ti = 341°C. The pyrochlore oxides seem to be a novel active alternative for catalytic soot oxidation. [Copyright &y& Elsevier]