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In this work, we reported the FeS2@C nanocapsules-modified petal-shaped MoS2 nanosheets (MoS2/FeS2@C) peroxidase prepared by arc discharging combined with hydrothermal methods. We thoroughly investigated their peroxidase-like activities in the colorimetric detection of H2O2 and glutathione (GSH). The results indicate that the prepared petal-shaped MoS2/FeS2@C nanocomposites exhibit enhanced peroxidase activity compared to the single-component MoS2 or FeS2@C. The detection ranges and detection limits (LOD) are 1–150 μM and 0.43 μM for H2O2, respectively, while for GSH, they are 0.2–40 μM and 0.14 μM, respectively. The superior peroxidase-like activity of the MoS2/FeS2@C results from the synergy between the MoS2 and FeS2@C. This synergy creates abundant active sites and more substance shuttle channels, which increases the cyclic efficiency among Fe3+/Fe2+ and Mo6+/Mo4+ and improves the yield of hydroxyl radicals. As a result, the MoS2/FeS2@C nanocomposites acquired quick electron transport and improved peroxidase-like catalytic performance. Moreover, the MoS2/FeS2@C nanocomposites exhibit high stability and selectivity, retaining high-activity levels even after 30 days. These make them promising candidates for use in biosensing and catalysis applications. [ABSTRACT FROM AUTHOR]

The Ni@CN/WO3-δ ternary composites were constructed by a two-step method in this work, which includes solid-phase pyrolysis and arc-discharging technology. Herein, the content of WO3-δ in Ni@CN/WO3-δ ternary composites was adjusted utilizing the precursor H2WO4 amount. The result shows that the appropriate WO3-δ content in Ni@CN/WO3-δ ternary composites can effectively contribute to their cooperativity for electromagnetic parameters and impedance matching. As a result, the optimal reflection loss of the Ni@CN/WO3-δ ternary composites can achieve in -42.4 dB at a thickness of 2.0 mm, and an efficient absorption bandwidth is 4.08 GHz at a matching thickness of only 1.7 mm. The study further reveals that the synergistic effects between the oxygen vacancies from appropriate WO3-δ and the high conductivity of CN lead to the balance between impedance matching and attenuation capacity of the Ni@CN/WO3-δ ternary composites, resulting in excellent microwave absorption performances. This work gives a feasible strategy for preparing high-performance microwave absorbents by oxygen vacancies engineering in the future. [ABSTRACT FROM AUTHOR]

Background Basal ganglia hemorrhage (BGH) is a devastating neurologic disease with high morbidity and mortality, and its management is still controversial. We evaluated the effectiveness of surgical treatments for BGH and investigated computed tomography (CT) imaging features affecting the hematoma evacuation rate (ER) in patients treated with neuroendoscopic surgery. Materials and Methods A total of 104 BGH patients who underwent craniotomy, burr-hole drainage, or neuroendoscopic surgery were analyzed retrospectively. Clinical characteristics, imaging features, and postoperative complications were compared. Univariate and multivariate regression analyses were applied to identify imaging factors associated with ER. Results A significant difference in ER was observed: 78.4% in patients treated with neuroendoscopic surgery, 33.6% in patients treated with burr-hole drainage, and 82.5% in patients treated with craniotomy (p < 0.001). Similar results were observed for operative time (p < 0.001). Five cases (12.5%) of rebleeding were found in patients treated with burr-hole drainage (p = 0.020). No significant difference was found for pneumonia, intracranial infection, gastrointestinal bleeding, hospital mortality, hospital stay, expenses, 3-day Glasgow Coma Scale (GCS) scores after surgery, or GCS at discharge. The CT imaging feature, the island sign (p = 0.004), was observed as an independent factor correlated with lower ER for neuroendoscopic surgery. Conclusions The benefits and drawbacks of surgical treatments confirmed they have their own indications, and neuroendoscopic surgery may be relatively beneficial for BGH treatment. The island sign was an independent factor affecting ER for neuroendoscopic surgery. Therefore, comprehensive assessment of clinical data, especially the island sign, should be performed preoperatively in BGH patients. [ABSTRACT FROM AUTHOR]

In this study, we have reported nitrogen-doped graphite C coated Co nanocomposite (Co@CN) catalysts synthesized by one-step arc discharge method. The surface compositions, morphologies and the catalytic properties of the Co@CN nanocomposites were studied minutely. The results reveal that the prepared Co@CN nanocomposites have typical core-shell structure and show highly efficient catalytic performance in a reduction of 4-nitrophenol (4-NP), rhodamine and methylene blue. Their rate constant (Kapp) is 0.074 s−1 in a reduction of 4-NP, which is much higher than that of reported transition metal-based catalysts. Moreover, the overpotential of Co@CN is only 96 mV at a current density of 10 mA cm−2 in alkaline solution, showing high electrocatalytic activities in the hydrogen evolution reaction. The excellent synergistic effect between nitrogen-doped graphite C shell and magnetic Co core enables the Co@CN nanocomposites catalysts to hold abundant active sites and to transmit rapidly electron ability, resulting in Co@CN nanocomposite catalysts having a highly efficient catalytic nature. [ABSTRACT FROM AUTHOR]

LaOCl/C/MnO composites were prepared by a citric acid-assisted sol-gel route. The products (60 wt%)-paraffin composites show excellent microwave absorption properties. The optimal reflection loss (RL) of the samples is − 49 dB with a thickness of 2.4 mm at 9.5 GHz, effective bandwidth (RL < − 10 dB) can cover 2.2-14.2 GHz (12 GHz) at matching thickness of 2-7.5 mm. The excellent microwave absorption ability can be rationally attributed to multiple-dielectric relaxation processes, which contribute to the proper impedance matching and strong attenuation of microwave. [ABSTRACT FROM AUTHOR]

An array of coupled cavities, each of which contains a triangle-down-level atom, is investigated. An effective Hamiltonian can be achieved under the strong classical driving. We can control the transition between Mott-insulator and superfluid states by the classical driving. The frequency conversion in one site has the same effects of nonlinear in BH hamiltonian which can induce insulator-superfluid states. [ABSTRACT FROM AUTHOR]