Reductive amination of furfuryl alcohol, furfural and 5‐hydroxymethylfurfural (5‐HMF) were carried out on various metal catalysts. Over Raney Ni catalyst, we obtained the highest furfurylamine yields of 81.8 % and 94.0 % from furfuryl alcohol in absence and presence of H2, respectively. While furfural was used as the substrate, 100 % yield of furfurylamine could be achieved over Raney Ni under rather moderate conditions. Although 5‐HMF was completely converted over all catalysts used, the highest yield of 2,5‐bisaminomethylfuran (60.7 %) was obtained over Raney Ni at 160 °C in 12 h. The DFT calculations on the adsorption behavior of NH3 and H2 on different metal surfaces showed that the difference of the adsorption energy between NH3 and H2 on Ni is lower than those of other metals, indicating that less metal active sites on Ni surface is occupied by NH3, which leaves more active sites for dehydrogenation/hydrogenation reactions and in the end promotes the reductive amination reactions.

Switchable reductive amination of furfuryl alcohol to tetrahydrofurfurylamine and furfurylamine was realized by adding/not adding H2 over a RANEY® Ni catalyst.

To achieve a higher activity and reusability of a Ru-based catalyst, Ru nanoparticles were embedded in N-doped mesoporous carbon through a hard-template method. The catalyst showed excellent catalytic performance (314 h turnover frequency) and recyclability (reusable five times with 3 % activity loss) for the hydrogenolysis of levulinic acid to γ-valerolactone. Compared with the mesoporous carbon without N-doping and conventional activated carbon, the introduction of N-dopant effectively improved the dispersion of Ru nanoparticles, decreased the average size of Ru nanoparticles to as small as 1.32 nm, and improved the adsorption of levulinic acid, which contributed to the increase in the activity of the catalyst. Additionally, the embedding method increased the interaction between Ru nanoparticles and carbon support in contrast with the conventional impregnation method, thus preventing the Ru nanoparticles from migration, aggregation, and leaching from the carbon surface and therefore increasing the reusability of the catalyst.

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The visible-blind ultraviolet (UV) photodetector can detect UV signals and is not interfered by visible light or infrared light in the environment. In order to realize high-performance visible-blind UV organic...

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Background: Melasma is an acquired pigmentation disorder with challenges in treatment because of its refractory nature and high risk of recurrence.Objectives: This study aimed to compare the efficacy and side effects of 14 common therapies for melasma using a systematic review and network meta-analysis (NMA).Methods: The PubMed, Embase, and Cochrane Library databases were searched till December 2020 using the melasma area and severity index as a therapeutic index. A total of 59 randomized controlled trials (RCTs) met the inclusion criteria and were selected.Results: The ranking of relative efficacy compared with placebo in descending order was Q-switched Nd:Yag 1,064-nm laser (QSND), intense pulsed light, ablative fractional laser (AFL), triple combined cream (TCC), topical vitamin C, oral tranexamic acid (oTA), peeling, azelaic acid, microneedles (MNs), topical tranexamic acid (tTA), tretinoin, picosecond laser, hydroquinone (HQ), and non-AFL. Moreover, QSND was more effective than HQ and tTA against melasma. The ranking of percentage (%) of side effects in ascending order for each of 14 therapies with more than 80 participants was tretinoin (10.1%), oTA (17.6%), HQ (18.2%), AFL (20.0%), QSND (21.5%), TCC (25.7%), tTA (36.75%), peeling (38.0%), and MN (52.3%). Taking both efficacy and safety into consideration, TCC was found to be the most favorable selection among the topical drugs for melasma. QSND and AFL were still the best ways to treat melasma among photoelectric devices. oTA as system administration was a promising way recommended for melasma. Among 31 studies, 87% (27/31) studies showed that the efficacy of combination therapies is superior to that of single therapy. The quality of evidence in this study was generally high because of nearly 50% of split-face RCTs.Conclusions: Based on the published studies, this NMA indicated that QSND, AFL, TCC, and oTA would be the preferred ways to treat melasma for dermatologists. However, more attention should be paid to the efficacy and safety simultaneously during the clinical application. Most of the results were in line with those of the previous studies, but a large number of RCTs should be included for validation or update.Systematic Review Registration: identifier: CRD42021239203.

High performance photomultiplication-type organic photodetectors based on an AIE material were successfully fabricated by designing a device structure.