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ZnZrOx solid solution is a promising catalyst for the hydrogenation of CO2 to methanol, but precise design of the nanostructure to enhance catalytic performance remains a significant challenge. Herein, a ZnZrOx-based solid solution (ZnZrOx-MD) nanoparticle catalyst with uniform metal dispersion and remarkable CO2 activation ability was developed via calcination of metal–organic frameworks [MOFs, viz., PCN-223-(Zn)] with mixed metal (Zr and Zn) as solid precursors. It was found that the ZnZrOx-MD nanoparticle catalyst outperformed its counterparts prepared using a traditional deposition–precipitation method (ZnZrOx-TD). Furthermore, the effects of the micromorphology and crystal composition on the catalytic performance of ZnZrOx-MD were systematically investigated. Comprehensive characterization results reveal that ZnZrOx-MD contained abundant oxygen vacancies, large specific surface area, and uniform metal dispersion, which collectively contributed to its excellent CO2 hydrogenation performance, resulting in a high methanol selectivity of 77.2% at 320 °C. In situ DRIFTS experiments confirm the mechanism for the CO2 hydrogenation to methanol over the ZnZrOx nanoparticle catalysts involved the initial formation of HCOO* species, followed by subsequent hydrogenation to generate CH3O* and ultimately produce methanol. Overall, this work highlights the potential benefits of MOFs as thermal decomposition precursors for the fabrication of solid-state catalysts with unique properties. [ABSTRACT FROM AUTHOR]

A Supported gold catalyst was prepared by reduction of HAuCl4 with the Cacumen Platycladi extract. This catalyst was then used for oxidation of 2-phenylethyl alcohol in a model reaction. Our study evaluated the effect of various preparation conditions, including the Au loading ratio and calcination temperature. Additionally, we explored the influence of the reaction temperature and reaction time on the catalytic performance of a Au/TiO2 catalyst. Our experimental findings revealed notable results for the Au/TiO2 catalyst characterized by the Au loading of 1.3 wt % and calcinated at 400°C. Under specific reaction conditions (0.3 g catalyst, 220°C, 3.0 MPa, 2.5 h), the conversion of 2-phenylethyl alcohol reached 45.3 and a 59.6% selectivity and a 27.0% yield of the target product (phenylacetaldehyde). In addition, catalytic performance remained stable after 8 repeated uses. [ABSTRACT FROM AUTHOR]

At present, the whole world is facing the serious challenge of COVID-19, and it has reached a consensus that taking appropriate measures timely is the key to prevent and control infectious diseases. This paper proposes an algorithm to solve the problem of how to choose the most appropriate alternative from numerous alternatives in the limited time from the perspective of management. First of all, we have compared various data structures for keeping the comparison results of alternatives. After comparisons, we adopt the hesitant fuzzy incomplete probabilistic linguistic preference relation matrix to save the information which can keep the first-hand valuable collected data to the maximum extent; then, we can obtain the missing values with the help of the fault tree analysis method, which can consider both subjective evaluation data and objective historical data simultaneously. Meanwhile, the fault tree analysis method can find development laws with the help of similar infectious diseases that have occurred in the past. The definition of consistency index is also introduced which can measure whether there are contradictions and the degree of contradiction in the decision results. Only those data that meet the consistency requirements can be used for decision-making and then a method is proposed to effectively reduce the degree of inconsistency. The information aggregation method will be adopted subsequently, and we can obtain the ranking of alternatives. An instance with specific execution steps is also introduced to illustrate the feasibility and efficiency of the algorithm proposed in this paper; in the end, several types of comparisons with typical algorithms proposed by other scholars are carried out, and all the experimental results show that the algorithm proposed in this paper is effective and innovative in some aspects. [ABSTRACT FROM AUTHOR]

BACKGROUND Biosynthesis of Ag nanoparticles ( AgNPs) utilizing renewable materials and nontoxic chemicals has become highly desirable and is currently receiving tremendous attention. In this study, a facile and cellulose-based approach was developed to biosynthesize AgNPs through tandem hydrolysis of silver sulfate and cellulose under hydrothermal conditions. RESULTS Well-defined AgNPs of about 72.0 nm in size were biosynthesized with 0.30 g of cellulose at 200°C for 10 h. The particle sizes of the as-synthesized AgNPs were positively affected by the reaction temperature and time, but on the contrary were negatively affected by the amount of cellulose employed. The results from Fourier transform infrared spectroscopy showed that the cellulose-hydrolyzed products (saccharides or aldehydes) were accountable for the bioreduction of the Ag ions, and the C = O (C-O) groups in the aldehydes or saccharides played critical roles in capping the AgNPs. Additionally, in the presence of the as-synthesized AgNPs, enhanced surface fluorescence of methyl orange was achieved. CONCLUSION A biological and maneuverable strategy was successfully developed for the synthesis of AgNPs by a hydrothermal route through tandem hydrolysis of silver sulfate and cellulose. Thus, this environmentally friendly method is anticipated to be utilized for the biosynthesis of AgNPs and opens up avenues to prepare other metal nanoparticles from metal sulfates. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]