The utilization of carbon dioxide (CO 2 ), which is one of the main contributors to the greenhouse effect, has been a topic of global interest, from both fundamental and practical viewpoints. In addition to be the sources of carbon, CO 2 might also be utilized as an oxygen source or oxidant, because it can be considered to be a nontraditional (mild) oxidant and oxygen transfer agent. In this paper, CO 2 as an oxidant for the selective oxidative conversions of alkanes to alkenes has been reviewed, including methane coupling to ethylene, C 2 -C 4 alkanes dehydrogenation to their corresponding olefins, dehydroaromerization of lower hydrocarbons to benzene, and dehydrogenation of ethylbenzene to styrene. It has been shown that CO 2 has the potential to offer a promising alternative to oxygen for selective oxidation, whereas the catalyst development is the key to the applications.
The Kagome superconductors AV3Sb5 (A = K, Rb, Cs) have received enormous attention due to their nontrivial topological electronic structure, anomalous physical properties and superconductivity. Unconventional charge density wave (CDW) has been detected in AV3Sb5. High-precision electronic structure determination is essential to understand its origin. Here we unveil electronic nature of the CDW phase in our high-resolution angle-resolved photoemission measurements on KV3Sb5. We have observed CDW-induced Fermi surface reconstruction and the associated band folding. The CDW-induced band splitting and the associated gap opening have been revealed at the boundary of the pristine and reconstructed Brillouin zones. The Fermi surface- and momentum-dependent CDW gap is measured and the strongly anisotropic CDW gap is observed for all the V-derived Fermi surface. In particular, we have observed signatures of the electron-phonon coupling in KV3Sb5. These results provide key insights in understanding the nature of the CDW state and its interplay with superconductivity in AV3Sb5 superconductors.
Methanol was high-efficiently converted to p-xylene over a shape-selective Mg–Zn–Si-HZSM-5 catalyst, with fine modification of the pore-opening and acidic properties.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.