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The hydrolysis of Mg-based alloys and their hydrides with high abundance on the earth and low cost could produce hydrogen with high theoretical capacity and the formation of by-products that have no pollution to the environment. Hence, it has been regarded as one of the most promising way for hydrogen generation. Particularly, a gravimetric capacity of 6.4 wt% and 3.4 wt% H2 could be produced from the hydrolysis of pure Mg and MgH2, respectively, even when stoichiometric water is included for calculation. The formation of passive magnesium hydroxides with dense structure, however, could immediately interrupt the hydrolysis reaction of Mg/MgH2, which leads to ultralow yield and sluggish hydrogen generation rate. Recent studies have demonstrated that the hydrolysis reaction of Mg/MgH2 could be effectively enhanced in terms of both yield and kinetics by the formation of Mg-based alloys and their hydrides. This review aims to summarize the recent progress in the hydrolysis of Mg-based alloys and their hydrides and the involved hydrolysis mechanisms.

Recent developments of hot-extrusion 3D printing (HE-3DP) have made it possible to manipulate starch digestibility. This work investigated the regulating mechanism of starch-catechin (EC) interactions on rice starch digestibility during HE-3DP by using modern analytical techniques and computational models. The results showed that the HE-3DP processing with starch-EC interactions could significantly decrease the starch digestibility (p 0.05) due to the formation of ordered structures including short-range ordered structure, nano-aggregates and V-type crystalline structure. Meanwhile, molecular dynamics simulations were performed to reveal the mechanism of EC as an enzyme inhibitor to enhance the resistant starch contents of rice starch to 46.1%. Results showed that EC could loosely attach to starch chains, thereby facilitating binding to Trp59 of pancreatic α-amylase and preventing starch from binding to its active pocket. These findings provide useful structural information for EC to reduce starch digestibility in the HE-3DP environment.

Detailed knowledge about polymer flows through the anthroposphere and into the environment is information essential to the better management of plastics. Currently, only limited knowledge about specific polymer flows is available. This work aimed to model those flows for five polymers: polyurethane (PUR), acrylonitrile butadiene styrene (ABS), polyamide (PA), polycarbonate (PC) and polymethyl methacrylate (PMMA). Probabilistic material flow analysis (PMFA) was used to quantify flows from production in 45 product categories to their end-of-life in Europe and Switzerland. We then considered 40 release pathways for macro- and microplastic flows to assess polymer release into Switzerland's environment. PMFA results showed considerable variations between the polymers considered because their flows through the anthroposphere are determined by their different uses. Total macro- and microplastic emissions into Switzerland's environment in 2018 were estimated at masses of 208±76 t for PA, 179±98 t for PUR, 79±26 t for PC, 36±23 t for PMMA and 25±6 t for ABS. Relative to Switzerland's total production and imports, this amounted to total releases of 0.23% of PA, 0.07% of PUR, 0.16% of PC, 0.32% of PMMA and 0.14% of ABS. Contributions as released microplastics ranged from 18% of PMMA to 75% of ABS. These results showed that the amounts of the polymers considered released into the environment were much smaller than previously assumed in simpler release estimates, and they may be more realistic for countries with well-functioning waste treatment systems.

This work investigated the chain structure and large amplitude oscillatory shear (LAOS) rheological properties of waxy maize starch (WMS) at different growth periods and established a motion model to clarify the evolution of starch chain structure. During the growth period of 20–25 days, the apparent viscosity and dynamic moduli for WMS paste decreased, along with a greater degree of nonlinearity. This could be correlated with an increasing branching degree of starch due to more short-branched chains generated during growth. With the growth period reaching 25 days, the apparent viscosity, dynamic moduli and zero-strain nonlinearity (Q0) for WMS increased and the b value deviated from 2 significantly, indicating obvious nonlinearity accompanied by a weak stress overshoot and shear-thickening. This could be explained by the growing length of branched chains and the rising content of B3- and B4-chains. Thus, this work demonstrate LAOS rheology can be used as a new and effective method to characterize the chain structural evolution of starch through monitoring the motion pattern of different starch chains under shear conditions.

There are currently increasingly concerns over DNA damage related to free radicals due to their vital roles in human health, especially high-performance detection method. Herein, we report an ultra- sensitive monitoring of DNA damage associated with free radicals exposure using interdigitated electrode (IDE) array for the first time. The proposed IDE array was equipped with DNA-wrapped carbon nanotube-based bridges, which utilized the DNA damage mechanism due to the free radicals’ attack and the efficient electrical detection nature of the interdigitated electrode. Experiments have been performed, and the results showed the device’s capability for detecting DNA damage induced by multiple free radicals generated from different sources, including the Fenton reaction, UV radiation and cigarette smoke, showing the promising ability for DNA damage detection. In addition, the carbon nanotubes bridge-based interdigitated electrode sensor enabled different levels of sensing of DNA damage with great sensitivity and a wide detection range. It was illustrated that the ultrasensitive detection of free radicals generated from ultraviolet radiation (15 min – 125 min), cigarette smoke tar (1 μg/mL to 10 μg/mL) and Fenton reaction under different concentration of H2O2 (2.5 pM – 100 pM), have been detected successfully. Typically, the IDE array supports further performance improvement for the electrochemical detection in an ultrasensitive and high throughput route.

Matcha is a popular nutritious food ingredient with strong health benefits. The interplay between matcha and gluten is essential for developing high-quality matcha-noodles. Herein, the effects of matcha and its active components, l -theanine and tea polyphenol, on the structural and rheological properties of gluten had been investigated. The results showed that matcha weakened the dough strength by reducing disulfide bonds and hindering the formation of gluten network. However, l -theanine enhanced the ductility of dough by forming extra β-sheets and disulfide bonds, whereas tea polyphenol increased its toughness by forming numerous intermolecular hydrogen bonds with gluten to stabilize the “grid” structure. The underlying intermolecular mechanisms between gluten and l -theanine or tea polyphenol were clearly established. This study has provided valuable reference to produce nutritious noodles products with matcha or its active components.

Heavy metal elements, including Zn, Cd, As, Ni, Cu, Pb and Cr, were detected in soils (no deeper than 75 m) from newly reclaimed zones of Shanghai, China. The Zn concentration exceeded soil quality limits. The Zn contamination was tested in both dredger fills and sedimentary layers (①3-3, ②3, ④ and ⑤1-1). However, it was not detected in layer ⑤1-2-⑨. PCA and HCA analysis show that exogenous Zn probably was the contaminant source of dredger fills before the fills were dredged from the neighboring waters. Stochastic heterogeneity of the dredger fills affects the Zn-depollution remarkably. Numerical simulations show both acid precipitation and widespread drainage channels in the zones contributed to Zn-decrease in the dredger fills no deeper than 1.2 m. Acid rainstorms work better than acid constant precipitation in Zn-remediation for layers below 0.4 m. To remove Zn contamination in deep dredger fills, un-consolidation of the fills should be utilized.

N-Acetylcysteine (NAC) and allopurinol (ALP) synergistically reduce myocardial ischemia reperfusion (MI/R) injury in diabetes. However, the mechanism is unclear. We postulated that NAC and ALP attenuated diabetic MI/R injury by up-regulating phosphatidylinositol 3-kinase/Akt (PI3K/Akt) and Janus kinase 2/signal transducer and activator of transcription-3 (JAK2/STAT3) pathways subsequent to adiponectin (APN) activation. Control (C) or streptozotocin-induced diabetic rats (D) were untreated or treated with NAC and ALP followed by MI/R. D rats displayed larger infarct size accompanied by decreased phosphorylation of Akt, STAT3 and decreased cardiac nitric oxide (NO) and APN levels. NAC and ALP decreased MI/R injury in D rats, enhanced phosphorylation of Akt and STAT3, and increased NO and APN. High glucose and hypoxia/reoxygenation exposure induced cell death and Akt and STAT3 inactivation in cultured cardiomyocytes, which were prevented by NAC and ALP. The PI3K inhibitor wortmannin and Jak2 inhibitor AG490 abolished the protection of NAC and ALP. Similarly, APN restored posthypoxic Akt and STAT3 activation and decreased cell death in cardiomyocytes. Gene silencing with AdipoR2 siRNA or STAT3 siRNA but not AdipoR1 siRNA abolished the protection of NAC and ALP. In conclusion, NAC and ALP prevented diabetic MI/R injury through PI3K/Akt and Jak2/STAT3 and cardiac APN may serve as a mediator via AdipoR2 in this process.