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Direct methane conversion to acetic acid (DMCAA) offers a promising approach for transforming the abundant CH4 resources to value‐added chemicals, eliminating the multi‐step processes involving syngas generation and methanol carbonylation in traditional industrial routes. However, this reaction still faces great challenges, which primarily due to the stable C−H bond of methane and the difficulty in avoiding the over‐oxidation of products. Extensive researches have been conducted on the DMCAA process using different catalytic systems. This review summarizes the progress made in this field over the past decades and categorizes the research achievements according to homogeneous and heterogeneous systems, encompassing the investigations on catalytic mechanisms. Furthermore, the challenges and potential solutions in this field are discussed, which could provide valuable guidance for developing prospective catalysts towards DMCAA. [ABSTRACT FROM AUTHOR]

Direct methane conversion (DMC) to oxygenates at low temperature is of great value but remains challenging due to the high energy barrier for C−H bond activation. Here, we report that in situ decoration of Pd1‐ZSM‐5 single atom catalyst (SAC) by CO molecules significantly promoted the DMC reaction, giving the highest turnover frequency of 207 h−1 ever reported at room temperature and ~100 % oxygenates selectivity with H2O2 as oxidant. Combined characterizations and DFT calculations illustrate that the C‐atom of CO prefers to coordinate with Pd1, which donates electrons to the Pd1−O active center (L−Pd1−O, L=CO) generated by H2O2 oxidation. The correspondingly improved electron density over Pd−O pair renders a favorable heterolytic dissociation of C−H bond with low energy barrier of 0.48 eV. Applying CO decoration strategy to M1‐ZSM‐5 (M=Pd, Rh, Ru, Fe) enables improvement of oxygenates productivity by 3.2–11.3 times, highlighting the generalizability of this method in tuning metal‐oxo electronic structure of SACs for efficient DMC process. [ABSTRACT FROM AUTHOR]

Background and Aim Of the Study: Numerous anatomic relationships of arteries could cause extrinsic compression of the trachea or bronchus. We report a rare left bronchial stenosis just caused by shorter inter-aortic distance.Methods: One patient wih recurrent coughing and wheezing was diagnosed as left emphysema.Cardiac computed tomography (CTA) shows a shorter distance between ascending aorta (AAo) and descending aorta (DAo) caused left bronchial stenosis with extrinsic compression of right pulmonary artery.Results: A translocation of the descending aorta was performed in this patient, and postoperative CTA showed that the DAo was translocated to the AAo and the left main bronchial stenosis was relieved.Conclusions: Translocation of the DAo was necessary for the rare left bronchial stenosis caused by shorter inter-aortic distance and could bring a good outcome. [ABSTRACT FROM AUTHOR]