Search

AerMet 100 steel is a new type of double-hardened high-strength steel, which is often used as landing gear material in amphibious aircraft. In the present paper, the corrosion fatigue behavior and mechanism of AerMet 100 high-strength steel in a 3.5% NaCl solution was studied by stress-controlled fatigue tests and a series of subsequent characterizations of the fracture surface, microstructure, and cracks. The results indicated that the fatigue life of AerMet 100 high-strength steel decreased with a decrease in the stress level in a 3.5% NaCl solution, satisfying the relationship lgN = −2.69 × 10−3 σ + 6.49. The corrosion fatigue crack usually initiated from the corrosion pit and propagated across the martensitic flat noodles. Meanwhile, the corrosion fatigue crack tip was filled with Cr2O3, Fe2O3, and amorphous material; it propagated in the transgranular mode by a slip dissolution mechanism. This study provides some engineering significant for the fatigue performance of AerMet 100 steel in a 3.5% NaCl solution. [ABSTRACT FROM AUTHOR]

Objective To observe the clinical efficacy of teicoplanin combined with levocarnitine in treatment of methicillin-resistant Staphylococcus aureus (MRSA) infective endocarditis (IE). Methods A total of 84 patients diagnosed with IE caused by MRSA admitted to our hospital from March 2018 to February 2019 were perspectively recruited, and then randomly divided into control group (teicoplanin and placebo) and combined treatment group (teicoplanin and levocarnitine), 42 cases in each group. Cardiac function indexes, including stroke output (SV), cardiac output (CO) and left ventricular ejection fraction (LVEF) were observed before and after treatment. The clinical efficacy and bacterial clearance were evaluated and compared between the 2 groups. The levels of hypersensitivity C-reaction protein (hs-CRP) and procalcitonin (PCT), white blood cell count (WBC), and erythrocyte sedimentation rate (ESR) in the serum of the 2 groups before and after treatment were compared. Adverse reactions during treatment were counted and compared. Results There were no significant differences in cardiac function indexes between the 2 groups before treatment (P>0.05). While, SV, CO and LVEF were increased after treatment in both groups, and the above values in the combined group were significantly higher than those of the control group (P < 0.05). Statistical difference was seen in the distribution of efficacy grade between the 2 groups (P < 0.05), and the combination group had notably higher total effective rate (95.24% vs 80.95%), clearance rate (92.86% vs 76.19%) and total clearance rate (97.62% vs 83.33%) when compared with the control group (all P < 0.05). There were no significant differences in serum hs-CRP and PCT levels and WBC and ESR before treatment (P>0.05). The indexes were decreased after treatment, with those in the combined group more significant (all P < 0.05). No significant difference was found in the incidence of total adverse reactions between the 2 groups (P>0.05). Conclusion Teicoplanin combined with L-carnitine is safe and reliable, and can effectively improve the cardiac function, promote bacterial clearance rate, and effectively control infection in IE patients induced by MRSA.

Abstract Background Little research has focused on the relationship between health insurance and mental health in the community. The objective of this study is to determine how the basic health insurance system influences depression in Northwest China. Methods Participants were selected from 32 communities in two northwestern Chinese cities through a three-stage random sampling. Three waves of interviews were completed in April 2006, December 2006, and January 2008. The baseline survey was completed by 4,079 participants. Subsequently, 2,220 participants completed the first follow-up, and 1,888 completed the second follow-up. Depression symptoms were measured by the Center for Epidemiologic Studies Depression Scale (CES-D). Results A total of 40.0% of participants had at least one form of health insurance. The percentages of participants with severe depressive symptoms in the three waves were 21.7%, 22.0%, and 17.6%. Depressive symptoms were found to be more severe among participants without health insurance in the follow-up surveys. After adjusting for confounders, participants without health insurance were found to experience a higher risk of developing severe depressive symptoms than participants with health insurance (7 months: OR, 1.40; 95% CI, 1.09-1.82; p = 0.01; 20 months: OR, 1.89; 95% CI, 1.37-2.61; p Conclusion A lack of basic health insurance can dramatically increase the risk of depression based on northwestern Chinese community samples.

The USTB process with a consumable TiCxOy anode is considered as a low-cost and eco-friendly method for Ti production. However, the dendritic Ti products have disadvantages of high oxygen and salt contents. Here, a liquid Zn cathode was proposed to prepare Ti–Zn alloys from a casting TiC0.5O0.5 anode via a one-step electrolysis process in a NaCl–KCl molten salt. Cyclic voltammetry and square-wave voltammetry were used to investigate the electrochemical dissolution of Ti ions from a consumable TiC0.5O0.5 anode and subsequent reduction behavior on cathode. The results indicate that the reduction potential of Ti on a liquid Zn cathode is more positive than that on a solid W cathode. Ti2+ from the casting TiC0.5O0.5 anode was one-step reduced to Ti on the liquid Zn cathode. A quasi-reversible process was confirmed via diffusion-controlled mass transfer, and the diffusion coefficient of Ti2+ toward the liquid Zn electrode was 4.35 × 10−5 cm−2 s−1. The concentration of Ti2+ in molten salt is more stable during electrolysis with a liquid Zn cathode. Ti–Zn alloys were successfully prepared at a current density of 0.3 A cm−2 using a casting TiC0.5O0.5 anode and a liquid Zn cathode. Metallic Zn was confirmed to be a promising liquid cathode to prepare Ti–Zn alloys via the USTB process. [ABSTRACT FROM AUTHOR]

With the increasing demand for the efficient utilization of global resources, green strategies for the transformation of inferior coals to highly value-added products are largely required. In this study, a green approach was demonstrated for the conversion of inferior coals into crystalline graphite using a simple purification and high-efficiency electrochemical method. After being processed in the molten CaCl2 salt under 2.6 V at 950 °C for 6 h, the products presented a highly graphitic structure with high degree of graphitization. The as-prepared graphite was employed as a negative electrode material for lithium-ion batteries, delivering a highly reversible capacity of 510 mA h g−1 at 1C. High-performance lithium-ion storage represents an efficient green strategy to reuse inferior coals for conversion into value-added products via a more sustainable route. [ABSTRACT FROM AUTHOR]

In this paper, a Ni0.36Al0.10Cu0.30Fe0.24 metallic inert anode was proposed and the electrochemical behaviors were studied in molten K2CO3-Na2CO3 at 1023 K by polarization curves and Tafel plots. The results indicated that Ni0.36Al0.10Cu0.30Fe0.24 alloy was stable in carbonate due to the formation of a passivation film on the surface. The film was mainly composed of NiFe2O4 and Al2O3 with a dense structure, which inhibited further corrosion of anode. Moreover, oxygen gas and Fe-Ni alloy have been successfully generated through electrolysis with NiO-Fe2O3 pellet as cathode and Ni0.36Al0.10Cu0.30Fe0.24 alloy as anode under a potential of 1.9 V for 24 hours. Ni0.36Al0.10Cu0.30Fe0.24 alloy exhibited bright prospect as a potential candidate of inert anode for green metallurgical process. [ABSTRACT FROM AUTHOR]

It is extremely important to design and fabricate high capacitance and stable Coulombic efficiency capacitors for energy storage. Herein, nitrogen-doped graphene coated on flexible tantalum foil is developed as a cathode for aluminum-ion hybrid supercapacitors which are based on an ionic liquid electrolyte with 1-ethyl-3-methylimidazolium chloride ([EMIm]Cl)/AlCl3. The results demonstrate that the nitrogen-doped graphene cathode offers a high capacitance of 254 F g−1, a Coulombic efficiency of ∼90% and a cycle life of 1000 at a current density of 0.3 A g−1. Meanwhile, the nitrogen-doped graphene cathode shows a capacitance of ∼130 F g−1, a Coulombic efficiency of almost 100% and a cycle life of 2000 at a higher current density of 2.0 A g−1. Moreover, the energy storage mechanism of the nitrogen-doped graphene in the aluminum-ion hybrid supercapacitors, that is, the dominant electrical double-layer capacitance (the adsorption and desorption of AlCi4− on the surface), and the intercalation/deintercalation in the nitrogen doped graphene, are confirmed. [ABSTRACT FROM AUTHOR]

Salidroside (SAL) is the major pharmacologically active constituent of Rhodiola rosea, which possesses a wide range of pharmacological functions, including anti-aging, anti-inflammatory, antioxidant, anticancer and neuroprotective activities. However, the effects and mechanisms of SAL on oxidative stress in retinal pigment epithelial (RPE) cells exposed to hydrogen peroxide (H2O2) remain unclear. The present study investigated the protective effects of SAL and the underlying mechanisms against H2O2-induced oxidative stress in human RPE cells. ARPE-19 cells were treated with various doses of SAL for 24 h and then exposed to 200 µM H2O2 for 24 h. Cell viability was analyzed by a MTT assay, and the intracellular levels of reactive oxygen species were measured using CellROX orange reagent. Cell apoptosis was analyzed by annexin V/propidium iodide double staining, followed by flow cytometry. The levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein, phospho (p)-protein kinase B (Akt), Akt, p-glycogen synthase kinase (GSK)-3β and GSK-3β were evaluated using western blotting. The results demonstrated that SAL markedly attenuated H2O2-induced loss of cell viability. SAL also ameliorated H2O2-induced oxidative stress and cell apoptosis in RPE cells. In addition, pretreatment with SAL significantly increased the phosphorylation levels of Akt and GSK-3β in H2O2-treated ARPE-19 cells. In conclusion, the present study demonstrated that SAL protected RPE cells against H2O2-induced cell injury through the activation of the Akt/GSK-3β signaling pathway. This suggests that SAL may be a potential therapeutic strategy for the treatment of age-related macular degeneration. [ABSTRACT FROM AUTHOR]

Abstract: A flower‐like vanadium sulfide/reduced graphene oxide (VS4/rGO) composite was prepared by a typical hydrothermal method and it was investigated as cathode for aluminum‐ion batteries with non‐inflammable and non‐explosive ionic‐liquid electrolytes. The charge/discharge performance measurements were performed in a voltage range of 0.1–2.0 V versus Al/AlCl4−, which gave an initial charge/discharge specific capacity af approximately 491.57 and 406.94 mA h g−1, respectively, at a current density of 100 mA g−1. Additionally, in the cycling performance, the discharge capacity was observed to remain over 80, 70, and 60 mA h g−1 at current densities of 100, 200, and 300 mA g−1 after 100 cycles, respectively. The result of a coulombic efficiency over 90 % after 100 cycles and high retained capacity indicate that the composite is a favorable cathode material for new rechargeable aluminum‐ion batteries. [ABSTRACT FROM AUTHOR]