New Type of Catalyst for Efficient Aerobic Oxidative Desulfurization Based On Tungsten Carbide Synthesized by the Microwave Method.

Herein, we present a new type of high-performance catalyst for aerobic oxidation of organosulfur compounds based on tungsten carbide. The synthesis of tungsten carbide was performed via microwave irradiation of the precursors, which makes it possible to obtain a catalyst in just 15 min. The synthesized catalyst was investigated by a variety of physicochemical methods: X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, electron microscopy, and N2 adsorption/desorption. It was shown that active centers containing tungsten in the transition oxidation state (+4) play a key role in the activation of oxygen. The main factors influencing the conversion of dibenzothiophene (DBT) were investigated. It should be noted that 100% conversion of DBT can be achieved under relatively mild conditions: 120 °C, 3 h, 6 bar, and 0.5% wt catalyst. The catalyst retained its activity for at least six oxidation/regeneration cycles. The simplicity and speed of synthesis of the proposed catalyst in combination with its high activity and stability open broad prospects for its further use both for oxidative desulfurization and for other reactions of aerobic oxidation of organic substrates.

Homeostasis Disrupted and Restored-A Fresh Look at the Mechanism and Treatment of Obesity During COVID-19.

The prevalence of obesity in the United States approaches half of the adult population. The COVID-19 pandemic endangers the health of obese individuals. In addition, the metabolic syndrome poses a challenge to the health of obese adults. Bariatric surgery and diet restore metabolic homeostasis in obese individuals; however, it is still unclear which strategy is most effective. For example, intermittent fasting improves insulin sensitivity and diet alone decreases visceral adipose tissue at a disproportionately high rate compared to weight loss. Bariatric surgery causes rapid remission of type 2 diabetes and increases incretins for long-term remission of insulin resistance before meaningful weight loss has occurred. Malabsorptive surgeries have provided insight into the mechanism of altering metabolic parameters, but strong evidence to determine the duration of their effects is yet to be established. When determining the best method of weight loss, metabolic parameters, target weight loss, and risk-benefit analysis must be considered carefully. In this review, we address the pros and cons for the optimal way to restore metabolic homeostasis.