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A non-precious metal catalyst coated with carbon doped nitrogen supported cobalt by titanium oxide (Co/NC-TiO2-800) was prepared by hydrogen reduction at high temperature using poly (N-vinylimidazole), cobalt nitrate hexahydrate, and tetrabutyl titanate as the raw materials. The carbon network catalyst containing metal-nitrogen can effectively generate isolated active substances to catalyze the reduction amination reaction. Titanium oxide is introduced to stabilize cobalt nanoparticles on nitrogen-doped carbon, which enhances the stability of the catalyst. The samples were characterized by X-ray diffractometer (XRD), specific surface and aperture analyzer (BET), infrared spectrum analyzer (FT-IR), transmission electron microscope (TEM) and scanning electron microscope (SEM). The composition and structure of Co/NC-TiO2-800 were analyzed, and the active center and characteristics of Co/NC-TiO2-800 were revealed. The catalytic activity of Co/NC-TiO2-800 was tested using furfural reduction amination as the model reaction, and the reaction path was discussed. In addition, the effects of different nitrogen sources such as hydrazine hydrate, ammonia water and hydroxylamine hydrate on the reactivity were investigated. The results showed that the yield of furfuryl amine reached 99% at 100 °C and a H2 pressure of 2.0 MPa for 18 h with hydrazine hydrate as nitrogen source and hydrogen as hydrogen source. After 6 times of recycling, the catalytic activity is still high and has excellent stability. [ABSTRACT FROM AUTHOR]

Objective. The emerging literature on caregiving posits that anxiety is fairly prevalent and could vary with factors such as caregiving burden, mastery, and sleep quality. Little work has explained the possible dynamics between those variables. This study therefore aims to investigate the multiple serial mediations of mastery and sleep quality in the relationship between caregiving burden and anxiety among Chinese parental caregivers of children with leukemia. Method. Data were taken from a convenient sample (n = 342) from a nonprofit organization that provides psycho-social support to oncological patients and their families nationwide in China. The following standardized self-reported questionnaires were administered to parents of children with leukemia: Zarit Care Burden Scale, Personal Mastery Scale, Insomnia Severity Index, and Generalized Anxiety Disorder. A serial multiple mediation model (PROCESS model 6) was employed to test the mediation hypothesis. Result. It was demonstrated that caregiving burden was positively and significantly correlated with caregivers' anxiety. Bootstrap analyses indicate that there were direct and indirect effects of caregiving burden on anxiety, and it was mediated by mastery. In addition, sleep quality mediated the effects of caregiving burden and mastery on anxiety, respectively. Conclusion. Taken together, for parental caregivers of children with leukemia in China, caregiving burden is a primary stressor and can trigger anxiety. Low mastery and poor sleep quality are the secondary stressors that could lead to negative psychological outcomes for the caregiver. [ABSTRACT FROM AUTHOR]