Dynamic control of oxide nanostructures is crucial for the design of advanced oxide catalysts, which is also significant for understanding the active site and reaction mechanism in oxide catalysis.
　　Recently, a research team led by Prof. FU Qiang and Prof. BAO Xinhe from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) discovered that the reversible dynamic conversion between Cr oxide (CrOx) nanoislands with the same thickness and CrOx clusters with the identical size supported on Au(111) surface under different redox treatments.
　　This work was published in Proceedings of the National Academy of Sciences of the United States of America on May 23.
　　Dynamic transformation between bilayer islands and dinuclear clusters of Cr oxide on Au(111) through environment and interface effects (Image by NING Yanxiao and YI Zhiyu)
　　The researchers grew two kinds of well-defined CrOx nanostructures on Au(111) and unambiguously identified them by scanning tunneling microscopy and theoretical calculations.
　　They found that the CrOx nanoislands featured a CrO2-bilayer (BL) structure consisting of two Cr2O3 monolayers bridged by one layer of O, and the CrOx clusters had a Cr2O7 stoichiometry. Moreover, oxidation treatment in O3 could disperse the CrO2-BL nanoislands into the Cr2O7-dinuclear clusters, which could be dynamically converted back to the CrO2-BL by annealing in an ultrahigh vacuum.
　　Furthermore, surface science experiments and theoretical simulations revealed that both surface oxygen atoms dissociated from O3 and the confinement effect of the Au substrate played important roles in the formation of the Cr2O7-dinuclear clusters.
　　"The oxide nanocatalysts with controlled size and structure can be stabilized by the specific environment and oxide-metal interface", Prof. FU said.
　　This work was supported by the National Key R&D Program of China, the National Natural Science Foundation of China, and the Liaoning Revitalization Talents Program. (Text/image by NING Yanxiao and YI Zhiyu)

　　China is rich in coal resources but has comparatively limited crude oil and natural gas. Therefore, conversion of coal to clean liquid fuels, which are mainly synthesized by crude oil, has received much attention in China.
　　A research group led by Prof. DING Yunjie and Prof. ZHU Hejun from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) and their collaborators developed the activated carbon-supported Co catalysts to produce clean liquid fuels from syngas with high selectivity. Using these catalysts, they have realized industrially synthesizing 150 kt/a of clean liquid fuels from syngas derived from coal in slurry-bed reactors in Yulin, China.
　　The catalyst test showed that at the industrial facility's full load, the syngas' total conversion exceeded 98%, the selectivity of methane was less than 7%, and that of C3+ hydrocarbons/oxygenates exceeded 92%.
　　Fischer-Tropsch synthesis (FTS) is the most versatile process for converting syngas into various chemical products. Traditionally Co-based catalysts have poor selectivity of liquid which hinders their industrial applications.
　　The newly-developed Co-based catalysts were supported by carbon materials, leading to a high FTS activity, high C3+ selectivity, and good stability. Moreover, the catalysts could be recycled by the combustion method with no solid wastes.
　　"The direct conversion of syngas into clean liquid fuels using carbon material supported by a Co-based catalyst can be accomplished at an industrial scale in China, thereby creating more opportunities for clean and efficient use of coal resources," said Prof. DING. (Text by ZHAO Zi'ang)
　　The industrial facility of 150 kt/a of clean liquid fuels from syngas (Image by ZHAO Zi'ang)

Olefins, hydrogen, and carbon monoxide can be converted to aldehydes by the hydroformylation of olefins. Upon further conversion, chemicals including alcohols, acids, and esters are obtained.However, commercial hydroformylation mainly employs homogeneous technology, which can cause problems including separation between catalyst and product, leaching of precious metals and ligands, the massive solvent issues, and the inefficient use of the heat from the exothermic reaction.Now, a research team led by Prof. DING Yunjie and Prof. YAN Li from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) has realized highly-efficient industrial production of propanal/n-propanol via heterogeneous ethylene hydroformylation.Based on heterogeneous ethylene hydroformylation technology, the facility with propanal/n-propanol yield of 50 kt/year was put into operation in August 2020 in Ningbo, China. So far, it has been in stable operation for 22 months.The heterogeneous hydroformylation technology adopts porous organic polymers with large specific surface area and hierarchical porous structure as both carrier and ligand. It metalates rhodium ions to form single-Rh-sites catalyst with good performance and high stability using multiple Rh-P coordination bonds."The utilization rate of precious metals of this heterogeneous hydroformylation technology is nearly 100%, thereby making the leaching of precious metals and ligand negligible," said Prof. DING. "And there is no cost in the separation of catalyst and product in this process.""The reaction system is solvent-free, and the products have high purity. Moreover, a large amount of low-grade reaction heat can be efficiently used in the hydroformylation and hydrogenation reaction," said Prof. YAN. (Text by JIANG Miao)The industrial facility of 50 kt/year propanal/n-propanol by heterogeneous ethylene hydroformylation (Image by LI Cunyao)

　　A research group led by Prof. XIAO Jianping and Associate Prof. JIAO Feng from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. QU Zhenping from Dalian University of Technology, designed a tandem bifunctional zeolites-silver (Ag) catalyst that could boost formaldehyde oxidation at low temperatures.
　　This study was published in Nature Communications on April 22.
　　Bi-functional zeolites-sliver catalyst enabled tandem oxidation of formaldehyde at low temperatures (Image by LI Na and DONG Xue)
　　Theoretical calculations and experimental results showed the activity of formaldehyde oxidation was influenced by the separation between two components in bifunctional catalyst.
　　The researchers found a volcano trend for the separation between ZSM-5 and Ag nanoparticles, which means it's not "the closer, the better".
　　Detached acidic ZSM-5 activated formaldehyde could generate gaseous intermediates of methyl formate, which was more easily oxidized by subsequent components (Ag). The Ag component would inevitably adsorb unreacted formaldehyde molecules and thereby led to lower methyl formate oxidation activity when the two components were packed too close.
　　The methyl formate oxidation on Ag components obtained high activity by suppressing the formation of dioxymethylene (DOM), which was hard to be further oxidized.
　　Compared to that of monofunctional supported silver catalyst, the formaldehyde conversion was increased by 50 times (100% versus 2%) at 70 °C.
　　The study was supported by the National Key Research and Development Program, and the National Natural Science Foundation of China. (Text by JIAO Feng)

　　Cyclic GMP-AMP synthase (cGAS), a double-stranded DNA (dsDNA) sensing protein, plays an important biological function in the strong innate immune response induced by pathogen derived nucleic acids.
　　Previous studies have revealed the essential roles of cGAS in multiple biological processes, including pathogen invasion and autoimmune diseases. cGAS activity must be well regulated to maintain homeostasis, preventing both overinhibition and overactivation.
　　Recently, a research team led by Prof. LI Guohui from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. YIN Hang's group from Tsinghua University, revealed the molecular mechanism of ZDHHC18-mediated palmitoylation of cGAS to inhibit innate immunity.
　　This study was published in The EMBO Journal on April 19.
　　The researchers found that the palmitoyltransferase ZDHHC18 could inhibit the formation of 2:2 cGAS/DNA complex by palmitoylation of the C474 site of cGAS, thereby inhibiting the excessive activation of cGAS and negatively regulating cGAS biological activities.
　　Palmitoylation of the C474 site inhibits the dimerization of two 1:1 cGAS-DNA complexes (Image by LIU Ye)
　　"We found that palmitoylation of cGAS is a novel inhibitory mechanism of innate immune responses," said Prof LI. "It provides a potential target for drug development against viral infections and autoimmune diseases."
　　This work was supported by the National Natural Science Foundation of China. (Text by LIU Ye and CHU Huiying)

　　A research group led by Prof. PIAO Hailong from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) uncovered a new function of growth factor Midkine to suppress the Liver Kinase B1 / AMP-Activated Protein Kinase (LKB1-AMPK) axis in a noncanonical intracellular manner.
　　They found that by disrupting the LKB1-STRAD-Mo25 (STRAD: STE20-Related Kinase Adaptor) complex, Midkine decreased LKB1 activity and attenuated AMPK phosphorylation to promote cancer cell proliferation and tumor progression.
　　This study was published in Cell Death and Disease on April 29.
　　Midkine belongs to the pleiotrophin family growth factor and participates in diverse physiological processes. The expression of Midkine is upregulated in different types of human malignancy.
　　Like other growth factors, Midkine is secreted to extracellular space after signal peptide cleavage. Usually, the secreted Midkine is considered as a ligand, which binds to different transmembrane receptors to induce intracellular signaling.
　　Although a few studies have reported that the secreted Midkine can be transported back into cells through endocytosis, it is still unclear whether intracellular Midkine performs biological functions.
　　In this study, the researchers found that the relocalization of Midkine was highly efficient, and the internalized Midkine was mainly detected in the cytoplasm, indicating some unreported intracellular function of Midkine.
　　The researchers focused on AMPK signaling and found that Midkine suppressed AMPK phosphorylation at the Thr172 site of the α subunit. This resulted in the inactivation of AMPK in an intracellular dependent manner, as when Midkine was detained in extracellular space by heparin, the repression of Midkine to AMPK was relieved.
　　Furthermore, they found that Midkine suppressed AMPK activation through the upstream kinase LKB1. Mass spectrometry (MS) analysis combined with immunoprecipitation test proved that Midkine associated with LKB1 and STRAD to disrupt the LKB1-STRAD-Mo25 complex, which was indispensable for LKB1 activation.
　　By engineering the expression of Midkine and LKB1, the researchers verified that Midkine promoted cancer cell proliferation through the LKB1-AMPK axis. The analysis of clinical data also confirmed that the expression of Midkine was negatively related to AMPK activity and patient prognosis. (Text by XIA Tian)