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Gd 2 Zr 2 O 7 is considered a promising host material for immobilizing high-level radioactive waste. However, its interplay between grain sizes, radiation resistance and chemical stability is not well understood yet. Herein, Gd 1.7 Nd 0.3 Zr 0.5 Ce 1.5 O 7 ceramics with defect-fluorite phase and three different grain sizes (96, 390 and 1959 nm) were successfully fabricated and irradiated by 140 keV He ion beam up to a fluence of 8 × 1017 ions/cm2. Phase evolutions, microstructure changes and chemical stabilities were investigated. The nano-grained ceramic exhibits the lowest degree of amorphization and a delayed irradiation-induced lattice expansion and damage evolution process, demonstrating an enhanced ability in suppressing the coalescence of He bubbles inside the grain. Grain boundaries parallel to the surface were found to be more favorable sinks for irradiation-induced defects. Chemical stability tests showed that the 42 days leaching rates of all elements were between 10−7∼10−5 g/m2·d. All samples have maintained this superior chemical stability even after irradiation. Interestingly, the leaching test results also suggested that grain size may be not the primary factor influencing the long-term leaching rate. [ABSTRACT FROM AUTHOR]

In this paper, four kinds of silicon-rich biomass (rice husk, rice straw, peanut shell, corncob) were used as raw materials for SiO 2 extraction by heat treatment method. And the extracted SiO 2 was applied to prepare Ni/SiO 2 catalyst for acetic acid (AcOH) steam reforming. Various characterization methods were used to analyze the purity, structure and specific surface area characteristics of SiO 2 extracted from different sources. It was found that the silica prepared by acid washing and calcination (AWC) had larger specific surface area, abundant pore channels and larger pore volume. By water washing and calcination (WWC), K 2 O impurity would be remained in SiO 2 , which might dissolve SiO 2 during the calcination process, generating an increase in the pore size and a decrease in the specific surface area. While the CaO impurity in SiO 2 promoted the dispersion of the active components and enhanced the interaction between the active component and the carrier. A series of reforming catalysts were prepared by using the obtained SiO 2 as carriers. It was found that the lifetime of catalyst from low to high was Ni/RS-SiO 2

In order to obtain lithium disilicate glass-ceramics for dental restoration with both high strength and high translucency, lithium disilicate glass-ceramics with different MgO contents were prepared by melt-casting and heat treatment method. The effects of MgO content on the crystallization temperature, microstructure and flexural strength of lithium disilicate glass-ceramics were investigated. The results indicate that Mg2+ exists in the form of [MgO 4 ] in the network of lithium disilicate glass-ceramics when the MgO content is 0.56 mol% (M0.56), which is beneficial to increasing the homogeneity and thermal stability of the glass system, and short rod-like lithium disilicate crystals can be formed after heat treatment at 840°C. Thus, the obtained lithium disilicate glass-ceramics exhibit excellent comprehensive performance, with the flexural strength being 312 ± 23 MPa, and the average transmittance of visible light being 37.3% (d = 1.62 mm). Especially, the glass-ceramic sample shows better translucency than the commercially available products. The research results are of great significance for developing high performance lithium disilicate glass ceramics and promoting its broad application in the field of dental restoration. [Display omitted] • Lithium disilicate glass-ceramics with high flexural strength and good translucency were prepared. • The coordination number of Mg2+ with oxygen in the glass-ceramic is closely related to the content of MgO. • [MgO 6 ] is beneficial to crystallization of lithium disilicate and improvement of strength, but is not good for translucency. • [MgO 4 ] is conducive to improving the uniformity of lithium disilicate glass-ceramic, which is good for translucency. [ABSTRACT FROM AUTHOR]

Psychologic wellbeing can impact cardiovascular health. We aimed to evaluate the joint association of multiple psychologic wellbeing factors with cardiovascular diseases (CVD) and examine whether this association was modified by genetic susceptibility. In the UK Biobank, 126,255 participants free of CVD (coronary heart disease [CHD], stroke, and heart failure [HF]) at baseline, who completed a questionnaire on psychological factors, were included. The psychological wellbeing score was calculated by four factors: happiness, life satisfaction, broad depression, and neuroticism. Cox proportional hazard models were used to assess the association between the psychological wellbeing score and CVD risk. During the median follow-up of 11.5 years, 10,815 participants had newly diagnosed CVDs. Low life satisfaction, the presence of depression, and neuroticism score ≥1 were significantly associated with an increased risk of CVD in the multivariable-adjusted model. Through decreasing the psychological wellbeing score, there were significant increasing linear trends in the risk of CVD, CHD, stroke, and HF (all p for trend < 0.001). Participants with the lowest psychological wellbeing score had the highest risk for CVD (HR 1.51, 95% CI 1.42–1.61). Women were more susceptible to worse psychological wellbeing status for CVD than men (p for interaction = 0.009). The associations of the psychological wellbeing score with CVD were consistent across genetic risk (p for interaction >0.05). When considered jointly, participants exposed to high-risk psychological wellbeing and genetic status had a 2.70-fold (95% CI 2.25–3.24) risk for CHD. Joint exposure to multiple psychological wellbeing factors was associated with increased risks of incident CVD in an additive manner, regardless of genetic susceptibility. [Display omitted] • Multiple psychological wellbeing factors are associated with risk of cardiovascular diseases (CVD). • Psychological wellbeing score could be used in large populations as a combination indicator. • Lower psychologic wellbeing score is associated with increased CVD risk, regardless of genetic risk. • In CVD events, women are more vulnerable to poor psychological status than men. [ABSTRACT FROM AUTHOR]

A novel rod-shaped MIL-88A(Fe)@CuS featured with sulfur vacancies (S V) were constructed as heterogeneous catalysts for activating peroxymonosulfate (PMS) for coumarin (COU) degradation. A series of x MIL@CuS were obtained according to the mass content of MIL-88A(Fe) in the composites (x , wt% = 50 %, 65 %, and 80 %). Among them, 65 % MIL@CuS hold the best performance, and realized a complete COU removal (30 μM) in 7 min (0.2 g/L 65 %MIL@CuS and 0.5 mM PMS). The degradation was much more favorable in acidic initial pH than alkaline initial pH. The calculated reaction rate constants at initial pH of 3.0, 5.0, 6.0 and 9.0 were 0.903, 0.729, 0.650 and 0.095 min−1, respectively. Electron paramagnetic resonance (EPR) analysis, radical scavenging tests and mechanism exploration indicated that the main difference in degradation under acidic and alkaline pH came from the yield of 1O 2. In initial pH = 3.0 condition, S V and lattice oxygen on 65 %MIL@CuS participated in the generation of 1O 2 , greatly increasing the content of 1O 2 (11.6 × 10−11 M) and promoting the degradation. While under initial alkaline condition (pH = 9.0), 1O 2 were basically produced from the reaction between Cu(II) and PMS, resulting in a low yield (1.7 × 10−11 M) and lower degradation. Besides, 65 %MIL@CuS maintained excellent reusability with low metal ions leaching, and the degradation exceeded 98.0 % even in the fifth run. Overall, this work provided an efficient and stable activator for activating PMS to degrade refractory organics, and managed to disclose the activation mechanisms under acidic and alkaline pH. [Display omitted] [ABSTRACT FROM AUTHOR]