Quantum blockade and loop current induced by a single lattice defect in graphene nanoribbons

We investigate theoretically the electronic transport properties in narrow graphene ribbons with an adatom-induced defect. It is found that the lowest conductance step of a metallic graphene nanoribbon may develop a dip even down to zero at certain values of the Fermi energy due to the defect. Accompanying the occurrence of the conductance dip, a loop current develops around the defect. We show how the properties of the conductance dip depend on the parameters of the defect, such as the relative position and severity of the defect as well as the width and edges of the graphene ribbons. In particular, for metallic armchair-edges graphene nanoribbons, whether the conductance dip appears or not, they can be controlled by choosing the position of the single defect.Comment: 6 pages, 6 figure

Mechanical Properties of Thixoforged In Situ Mg2Sip/AM60B Composite at Elevated Temperatures

The mechanical behaviors of the thixoforged in situ Mg2Sip/AM60B composite at elevated temperatures were evaluated. The results indicated that the thixoforged composite exhibits higher UTS (ultimate tensile strength) than that of the thixoforged AM60B at the cost of elongation. As the testing temperature rises from 25 to 300 °C, the UTS of both these two materials decreases while their elongations increases. The enhanced dislocation motion ability, the softened eutectic β phase at 120 °C, the activated non-basal slipping and the dynamic recovery and recrystallization mechanisms at 150 °C are responsible for the change in tensile properties with testing temperatures. The fracture mode transforms from the ductile into the brittle as the initial strain rate increases from 0.01 to 0.2 s−1 at 200 °C

Synthesis of Nanocrystalline AZ91 Magnesium Alloy Dispersed with 15 vol.% Submicron SiC Particles by Mechanical Milling

The development of a magnesium matrix composite with a high content of dispersions using conventional liquid-phase process is a great challenge, especially for nanometer/submicron particles. In this work, mechanical milling was employed to prepare nanocrystalline AZ91 dispersed with 15 vol.% submicron SiC particles (SiCp/AZ91). AZ91 with no SiCp was applied as a comparative study with the same mechanical milling. In order to investigate the mechanism of dispersing, the morphology evolution of powders and the corresponding SiCp distribution were observed. As the scanning electron microscope (SEM) analysis exhibited, the addition of SiCp accelerated the smashing of AZ91 particles, which promoted the dispersion of SiCp in AZ91. Thus, after mechanical milling, 15 vol.% SiCp, which was smashed from 800 to 255 nm, got uniformly distributed in the Mg matrix. Based on X-ray diffraction (XRD) results, part of the Mg17Al12 precipitate got dissolved, and an Al-supersaturated Mg solid solution was formed. The transmission electron microscopy (TEM) results showed that the ultimate Mg grain (32 nm) of milled SiCp/AZ91 was much smaller than that of milled AZ91 (64 nm), which can be attributed to a pinning effect of submicron SiCp. After mechanical milling, the hardness of SiCp/AZ91 reached 185 HV, which was 185% higher than the original AZ91 and 33% higher than milled AZ91, due to fine Mg grain and submicron dispersions

Musculus senhousei as a promising source of bioactive peptides protecting against alcohol-induced liver injury

Alcohol-induced liver injury has become a leading risk for human health, however, effective strategies for the prevention or treatment are still lacking. Hence, the present study explored the potential of Musculus senhousei as a source of hepatoprotective peptides against alcoholic liver injury using in vitro, in vivo and in silico methods. Results indicated that Musculus senhousei peptides (MSP, extracted by simulated gastrointestinal digestion of cooked mussel) exhibited notable antioxidant (ABTS and DPPH assays) and alcohol dehydrogenase (ADH) stabilizing activity in vitro. The ingestion of MSP markedly alleviated alcohol-induced liver injury in mice, as indicated by the decrease of serum transaminases (AST and ALT). In line with in vitro assays, significantly increased hepatic ADH activity and activated antioxidative defense system (GSH, SOD, GSH-Px and CAT) were observed, whereas the oxidative stress (MDA) was decreased. Peptidomic analysis revealed over 6000 peptides with favorable amino acid compositions, and a total of 20 potentially novel peptides with bioactivity and bioavailability were excavated among 746 of the most influential peptides using an in silico strategy. Peptides (i.e. WLPMKL, WLWLPA, RLC and RCL) were further synthesized and validated in vitro to be bioactive. These findings suggest that Musculus senhousei can be an ideal source of bioactive peptides for the prevention of alcoholic liver injury.This work was supported by the Key-Area Research and Development Program of Guangdong Province (2022B0202030001 and 2021B0707060001), the National Natural Science Foundation of China (No. 32101896) and Self-innovation Research Funding Project of Hanjiang Laboratory (HJL202010B002).Peer reviewe

Effects of Graphite Particle Content and Holding Time on the Microstructure and Mechanical Properties of the Graphite/AZ91D Composite

The effects of Grp (graphite particles) addition and holding time on the microstructure and mechanical properties of the Grp/AZ91D composite were investigated in this work. The results indicated that the distribution of Grp in the matrix was determined by the self-stabilizing mechanism and relationships between the solidifying interface and the particles. Due to the self-stabilizing mechanism, a small amount of Grp would uniformly distribute in the melt alloy, and as the amount of Grp increased, agglomeration would occur. Accordingly, the former would be engulfed by the solidifying interface and the latter would be pushed. With an increased holding time, Grp tended to agglomerate, due to the interfacial reaction that occurred, and as a result, the solidifying interface will push it. The Grp/AZ91D composite with the addition of 1.5 wt.% Grp and a holding time of 15 min obtained grains 30.2 μm in size with a hardness of 89.07 HV, which was a decrease of 83.04% and increase of 35.06% compared to AZ91D, respectively

Cellulose-based functional gels and applications in flexible supercapacitors

In order to resolve the global crisis of fossil energy shortage and climate warming, the development of efficient energy storage devices is a significant topic at present. Supercapacitors as the novel type of energy storage devices have the unique advantages, including the fast charging/discharging behaviors, high-energy/power density, and stable cycling performance. Compared with traditional supercapacitors, flexible supercapacitors are environmentally friendly, light weight, small size and high safety. Therefore, flexible supercapacitors have a wide application prospect in emerging electronic devices. Due to its flexibility, biocompatibility, and structure designability, cellulose and its gel materials are gradually used as electrodes, separators and electrolytes in flexible supercapacitors. Several construction processes at molecular scale for high-performance cellulose gels are summarized. Meanwhile, this review covers the recent progress of developing the flexible supercapacitors and all-in-one supercapacitors based on cellulose functional gels. We finally discussed the potential challenges and opportunities for cellulose and its derived materials in new-style flexible supercapacitors and other electronic devices

Electroplating of non-fluorinated superhydrophobic Ni/WC/WS₂ composite coatings with high abrasive resistance

Weak hierarchical rough structures on superhydrophobic surfaces hinder their practical industrial applications. This paper reports a strategy to fabricate robust nickel-based superhydrophobic coatings via the codeposition of nanosized WS2 and WC particles. The Ni/WC/WS2 composite coatings were synthesized on mild steel substrates by one-pot electroplating followed by the adsorption of stearic acid self-assembled monolayers to modify the surface wetting. The particle concentration in the bath was investigated and the maximum water contact angle of approx. 170° was achieved by optimizing the particle contained. Hardened by WC and lubricated by WS2 inclusions the superhydrophobic coatings showed remarkable abrasive resistance with a bearing capacity ≥10,000 mm abrasion length. The coatings also showed aerophilic behavior and good environmental stability over >6 months

Perioperative Allogenenic Blood Transfusion Is Associated with Worse Clinical Outcomes for Hepatocellular Carcinoma: A Meta-Analysis

<div><p>Background and Objective</p><p>The impact of perioperative allogenenic blood transfusion (ABT) on clinical outcomes for hepatocellular carcinoma (HCC) is conflicting and unclear. The aim of this meta-analysis is to evaluate the association between ABT and HCC clinical outcomes. Outcomes evaluated were all-cause death, tumor recurrence and postoperative complications.</p> <p>Methods</p><p>Relevant articles were identified through MEDLINE search (up to November 2012). Meta-analyses were performed by using the fixed or random effect models. Study heterogeneity was assessed by Q-test and I² test. Publication bias was evaluated by funnel plots, Egger′s and Begg’s test.</p> <p>Results</p><p>A total of 5635 cases from 22 studies finally met our inclusion criteria. Meta-analysis indicated HCC patients with ABT had an increased risk of all-cause death at 3 and 5 years after surgery (respectively: OR = 1.92, 95% CI, 1.61–2.29,P<0.001; OR = 1.60, 95% CI, 1.47–1.73,P<0.001 ) compared with those without ABT. The risk of tumor recurrence was significantly higher for ABT cases at 1, 3 and 5 years (respectively: OR = 1.70, 95% CI, 1.38–2.10, P<0.001; OR = 1.22, 95% CI, 1.08–1.38, P<0.001; OR = 1.16, 95% CI, 1.08–1.24, P<0.001). The HCC cases with ABT significantly increased postoperative complications occurrence compared with non-ABT cases (OR = 1.78,95% CI, 1.34–2.37, P<0.001).</p> <p>Conclusions</p><p>The findings from the current meta-analysis demonstrated that ABT was associated with adverse clinical outcomes for HCC patients undergoing surgery, including increased death, recurrence and complications. Therefore, ABT should not be performed if possible.</p> </div