Search

Electrocatalytic urea synthesis via coupling of nitrate with CO2 is considered as a promising alternative to the industrial urea synthetic process. However, the requirement of sub‐reaction (NO3RR and CO2RR) activities for efficient urea synthesis is not clear and the related reaction mechanisms remain obscure. Here, the construction, breaking, and rebuilding of the sub‐reaction activity balance would be accompanied by the corresponding regulation in urea synthesis, and the balance of sub‐reaction activities was proven to play a vital role in efficient urea synthesis. With rational design, a urea yield rate of 610.6 mg h−1 gcat.−1 was realized on the N‐doped carbon electrocatalyst, superior to that of noble‐metal electrocatalysts. Based on the operando SR‐FTIR measurements, we proposed that urea synthesis arises from the coupling of *NO and *CO to generate the key intermediate of *OCNO. This work provides new insights and guidelines into urea synthesis from the aspect of activity balance. [ABSTRACT FROM AUTHOR]

It has been previously shown that (never in mitosis gene A)‐related kinase 2 (NEK2) is upregulated in multiple myeloma (MM) and contributes to drug resistance. However, the mechanisms behind this upregulation remain poorly understood. In this study, it is found that amplification of NEK2 and hypermethylation of distal CpG islands in its promoter correlate strongly with increased NEK2 expression. Patients with NEK2 amplification have a poor rate of survival and often exhibit TP53 deletion, which is an independent prognostic factor in MM. This combination of TP53 knockout and NEK2 overexpression induces asymmetric mitosis, proliferation, drug resistance, and tumorigenic behaviors in MM in vitro and in vivo. In contrast, delivery of wild type p53 and suppression of NEK2 in TP53−/− MM cell lines inhibit tumor formation and enhance the effect of Bortezomib against MM. It is also discovered that inactivating p53 elevates NEK2 expression genetically by inducing NEK2 amplification, transcriptionally by increased activity of cell cycle‐related genes like E2F8 and epigenetically by upregulating DNA methyltransferases. Dual defects of TP53 and NEK2 may define patients with the poorest outcomes in MM with p53 inactivation, and NEK2 may serve as a novel therapeutic target in aggressive MM with p53 abnormalities. [ABSTRACT FROM AUTHOR]

NO is a harmful pollutant to the environment. The traditional removal of NO is hindered by the harsh operating conditions and sacrifice of value‐added chemicals. Efficient electrocatalytic oxidation of NO was achieved over plasma‐treated commercial carbon cloth, serving as a promising anode substitution reaction to couple with the hydrogen evolution reaction without consumption of hydrogen‐containing resources. The introduction of carboxyl groups onto the carbon cloth boosted the electrocatalytic activity via the enhancement of NO chemisorption. Only potentials of 1.39 V and 1.07 V were applied to reach the current density of 10 mA cm−2 in neutral and acidic conditions, respectively, which is superior to the state‐of‐the‐art electrocatalysts for oxygen evolution. Energy and environmental concerns on fossil‐fuel‐derived hydrogen production, ammonia manufacture and nitrate synthesis, are greatly alleviated. This work provides an original strategy to realize the resource utilization of NO, the sustainable nitrate synthesis and hydrogen production in a green and economical way. [ABSTRACT FROM AUTHOR]

The industrial urea synthesis consists of two consecutive processes, nitrogen + hydrogen → ammonia followed by ammonia + carbon dioxide → urea. The electrocatalytic coupling of carbon source (carbon dioxide) and nitrogen source (nitrogen, nitrite, nitrate) by skipping the ammonia synthetic process might be a promising alternative to achieve the efficient urea synthesis; in this case, two industrial steps with high energy consumption and high pollution are optimized into one renewable energy‐driving electrocatalytic process. Herein, the progress of green urea synthesis is summarized, focusing on the electrocatalytic coupling of carbon source and nitrogen source for direct urea synthesis under ambient conditions. The mechanism researches for urea synthesis are also reviewed, and the future development directions of electrocatalytic urea synthesis are prospected. The electrocatalytic C–N coupling reaction realizes the efficient resource utilization and provides guidance and reference for molecular coupling reactions. [ABSTRACT FROM AUTHOR]

Co‐based spinel oxides, which are of mixing valences with the presence of both Co2+ and Co3+ at different atom locations, are considered as promising catalysts for the electrochemical oxidation of 5‐hydroxymethylfurfural (HMF). Identifying the role of each atom site in the electroxidation of HMF is critical to design the advanced electrocatalysts. In this work, we found that Co2+Td in Co3O4 is capable of chemical adsorption for acidic organic molecules, and Co3+Oh play a decisive role in HMF oxidation. Thereafter, the Cu2+ was introduced in spinel oxides to enhance the exposure degree of Co3+ and to boost acidic adsorption and thus to enhance the electrocatalytic activity for HMF electrooxidation significantly. [ABSTRACT FROM AUTHOR]