Association between long working hours and mental health among nurses in China under COVID-19 pandemic: based on a large cross-sectional study.

OBJECTIVE: Nurses were more likely to experience mental disorders due to long working hours and irregular schedules. However, studies addressing this issue are scarce; therefore, we aimed to investigate the association between long working hours and mental health in Chinese nurses during the coronavirus disease pandemic. METHODS: A cross-sectional study was conducted with 2,811 nurses at a tertiary hospital in China from March to April 2022. We collected data on demographic, psychological characteristics, dietary habits, life, and work-related factors using a self-reported questionnaire and measured mental health using Patient Health Questionnaire-9 and General Anxiety Disorder-7. Binary logistic regression to determine adjusted odds ratios and 95% confidence intervals. RESULTS: The effective response rates were 81.48%, 7.80% (219), and 6.70% (189) of the respondents who reported depression and anxiety, respectively. We categorized the weekly working hours by quartiles. Compared with the lowest quartile, the odds ratios and 95% confidence intervals across the quartiles for depression after adjustment were 0.98 (0.69, 1.40), 10.58 (2.78, 40.32), and 1.79 (0.81, 3.97) respectively, the P for trend was 0.002. The odds ratios across the quartiles for anxiety after adjustment were 0.87 (0.59, 1.30), 8.69 (2.13, 35.46), and 2.67 (1.26, 5.62), respectively, and the P for trend was 0.008. CONCLUSIONS: This study demonstrated that extended working hours increased the risk of mental disorders among nurses during the coronavirus disease pandemic, particularly in those who worked more than 60 h per week. These findings enrich the literature on mental disorders and demonstrate a critical need for additional studies investigating intervention strategies.

Ag nanoparticles-decorated CoAl-layered double hydroxide flower-like hollow microspheres for enhanced energy storage performance.

Layered double hydroxides (LDHs) have been considered as one class of promising active electrode materials for supercapacitors due to their tunable composition and chemical versatility. Nonetheless, the poor electrical conductivity hinders their further practical applications in supercapacitors. Herein, CoAl LDH flower-like hollow microspheres are decorated with Ag nanoparticles by a facile one-step solvothermal reaction, followed by chemical bath deposition reaction. Experimental results and theoretical calculations indicate that decorating Ag nanoparticles onto CoAl LDH not only reduces the energy band gap and enhances their electrical conductivity, but also promotes fast diffusion kinetics of electrolyte ions and electrochemical reaction activity. Consequently, the prepared Ag/CoAl LDH electrode demonstrates improved specific capacities of 1214 (825) C g-1 at 3 (30) A g-1 and 91% capacity retention over 10,000 cycles at 10 A g-1 compared to the pristine CoAl LDH electrode. Moreover, using Ag/CoAl LDH and N-doped carbon nanotubes as the positive and negative electrodes, respectively, the assembled hybrid capacitor device delivers an energy density of 61.2 Wh kg-1 at a power density of 800 W kg-1. This work may showcase a great promise of engineering conductive nanoparticles-decorated LDHs-based active materials towards high-performance supercapacitors.

Construction of ultra-stable trinickel disulphide (Ni3S2)/polyaniline (PANI) electrodes based on carbon fibers for high performance flexible asymmetric supercapacitors.

Highly flexible supercapacitors (SCs) have attracted significant attention in modern electronics. However, it has been found that flexible, metal sulfide-based electrodes usually suffer from corrosion, instability and low conductivity, which significantly limits their large scale application. Herein, we report on an electrode comprised of highly stable, free-standing carbon fiber/trinickel disulphide covered with polyaniline (CF/Ni3S2@PANI). This electrode was prepared and then employed in a high-performance of flexible asymmetric SCs (FASC). The coating layer of polyaniline served as both a protector and conducting shell for the Ni3S2 due to the nature of the highly stable N-Ni bonds that formed between the polyaniline and Ni3S2. In addition, the lightweight carbon fiber support served as both a current collector and flexible support. The prepared CF/Ni3S2@PANI electrode exhibited a significantly enhanced specific capacity (715.3 F·g-1 at 1 A·g-1) compared with the carbon fiber/Ni3S2 electrode (318 F·g-1 at 1 A·g-1). More importantly, the assembled FASC device delivered an impressive energy density of 35.7 Wh·kg-1 at a power density of 850 W·kg-1. The FASC device benefited from the interconnected flexible microstructure and the stable bond bridges, so that it could be bent into various angles without noticeably impairing its performance. This effective protective strategy may further inspire the design and manufacture of metallic oxide or sulfide electrode with ultrahigh-stability interbond bridges for high-performance flexible supercapacitors.

Ag/MnO2 Nanorod as Electrode Material for High-Performance Electrochemical Supercapacitors.

A one-dimensional hierarchical Ag nanoparticle (AgNP)/MnO2 nanorod (MND) nanocomposite was synthesized by combining a simple solvothermal method and a facile reduction approach in situ. Owing to its high electrical conductivity, the resulting AgNP/MND nanocomposite displayed a high specific capacitance of 314 F g-1 at a current density of 2 A g-1, which was much higher than that of pure MNDs (178 F g-1). Resistances of the electrolyte (Rs) and charge transportation (Rct) of the nanocomposite were much lower than that of pure MNDs. Moreover, the nanocomposite exhibited outstanding long-term cycling ability (9% loss of initial capacity after 1000 cycles). These results indicated that the nanocomposite could serve as a promising and useful electrode material for future energy-storage applications.

Ordered hexagonal mesoporous aluminosilicates with low Si/Al ratio: synthesis, characterization, and catalytic application.

Ordered hexagonal mesoporous aluminosilicates with lower Si/Al ratio below 5 have been successfully synthesized via the co-assembly of preformed aluminosilicate precursors with Gemini surfactant [C12H25N+(CH3)2(CH2)6N+(CH3)2C12H25] x 2Br(-) as the template. Powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, N2 adsorption-desorption isotherm measurements, Fourier transform infrared spectroscopy, 27Al nuclear magnetic resonance, thermogravimetric analysis, and temperature-programmed desorption of cyclohexylamine are employed to characterize the resulting samples. The phenol alkylation reaction is carried out to evaluate their catalytic performances. These studies indicate that the sample with a low Si/Al ratio of 3 still retains a highly ordered hexagonal mesoporous structure. And it also possesses the highest acidity of 0.96 mmol among the samples with lower Si/Al ratios below 5 due to its higher specific surface area together with more content of tetrahedrally coordinated Al in the framework. The catalytic tests confirm that the acidity of the samples plays a key role in determining their catalytic performances.

Template-free synthesis of mesoporous hollow CuO microspheres as anode materials for Li-ion batteries.

We report the preparation and characterization of mesoporous hollow CuO (MPH-CuO) microspheres by thermal decomposition of hollow copper oxalate microspheres synthesized via the reaction of ammonium oxalate and copper chloride without using any template. The sample was characterized by Nitrogen adsorption, X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. The electrochemical performance of MPH-CuO microspheres as anode materials in Li-ion batteries was evaluated. It was found that the MPH-CuO microspheres possessed an average diameter of 2.5 microm, a pore size of 17.5 nm, and a BET surface area of 15.2 m2/g. Their shells were composed of CuO nanocrystals with a size of 17.9 nm. Compared with the dense CuO microspheres, the obtained MPH-CuO shows an enhanced electrochemical performance with a higher capacity of 599.4 mAh/g and a better cyclability (484 mAh/g after 15 cycles) because of its mesoporous hollow structure that provides quick intercalation and large accommodation of lithium ions together with short diffusion distance for lithium ions, suggesting a potential application in Li-ion batteries.

Facile solvothermal synthesis of porous cubic Cu microparticles as copper catalysts for Rochow reaction.

Porous cubic Cu microparticles were synthesized by a facile solvothermal method using Cu(CH(3)COO)(2)·H(2)O as the Cu precursor and NaOH in a solution containing ethanol, ethylene glycol, and water. The synthesis conditions were investigated and a growth process of porous cubic Cu microparticles was proposed. The catalytic properties of the porous Cu microparticles as model copper catalysts for Rochow reaction were explored. The samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, temperature-programmed reduction, and nitrogen adsorption. It was found that the morphology and structure of the porous cubic Cu microparticles are highly dependent on the reaction time and temperature as well as on the amount of reactants added. Compared to the commercial Cu microparticles with irregular morphology and dense internal structure, porous cubic Cu microparticles show much higher dimethyldichlorosilane selectivity and Si conversion via Rochow reaction, which are attributed to the enhanced formation of active Cu(x)Si phase and gas transportation in the presence of the pore system within microparticles, demonstrating the significance of the pore structure of the copper catalysts in catalytic reactions of organosilane synthesis.

Fluorescent hybrid with electron acceptor methylene viologen units inside the pore walls of mesoporous MCM-48 silica.

A fluorescent material with methylene viologen units bonded into the pore walls of the mesoporous MCM-48 silica is synthesized using the method of periodic mesoporous organosilicas with bridging groups (PMOs), in which the methylene viologen units are located within the channel walls through the cohydrolysis and cocondensation of dichloride of N,N'-bis(triethoxysilylmethyl)-4,4'-bipyridinium (VP) and tetraethoxysilane (TEOS). It is found that the suspension of the hybrid emits fluorescence at ca. 380 and 420 nm, which is attributed to the S(1) state (pi* --> pi) of the viologen and the charge-transfer complex between the bipyridinium units as electron acceptor and accompanying halide (Br(-), Cl(-)) as donor components, respectively. The fluorescent emission intensity increases with increasing the amount of the VP covalently bonded to MCM-48 framework. The fluorescent intensity of VP adsorbed on the surface of the pore channel of MCM-48 was greatly weaker than that of the hybrid MCM-48-VP at the same molar ratio of TEOS to VP. No fluorescence was observed for pure VP. The different fluorescent intensity is ascribed to the fact that restricted degree of the rotation between two pyridine rings is different. It could be prospected that this material is potentially applied in drug delivery and fluorescence probing for medical diagnosis and synchronous therapy.