Due to its zero carbon, safe storage, and high energy density, liquid ammonia is a promising marine fuel in the shipping industry.
　　However, ammonia is a common toxic gas that can cause irritation to the mucous membranes and respiratory system. Therefore, it's necessary to develop a real-time and accurate monitoring method for long-distance sea voyages.
　　Recently, a research group led by Prof. FENG Liang from the Dalian Institute of Chemical Physics(DICP) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. XU Minyi's group from Dalian Maritime University, developed a full-set wireless self-powered ammonia leakage monitor system for ammonia-energy ships.
　　The system includes a honeycomb triboelectric nanogenerator (TENG) based power generation system, a carbon nanotube doped polypyrrole (CNTs-PPy)-based ammonia detection system, and a signal collecting and transmitting system (bluetooth).
　　This study was published in Nano Energy on April 11.
　　The researchers improved the electronic conduction efficiency via the synergistic effect between the carbon nanotubes and conductive polymers, which enhanced the sensing performance at room temperature. The sensor exhibited good performance with a low detection limit (0.2 ppm), short response time (about 90 s), high selectivity, good stability, and low cost.
　　Moreover, attributed to the bluetooth, the researchers realized wireless transmission from the detection module to the computer terminal.
　　By combining with the honeycomb structure TENG provided by Dalian Maritime University, the system could collect and covert the mechanical energy generated by the vibration of the ship's engine into electrical energy, realizing self-driving of the entire sensing system.
　　Furthermore, the researchers tested the system on the expedition ship. The entire sensing system worked smoothly in the low-level cabin of the ship with high temperature and high humidity, confirming its potential in practical applications.
　　"The self-powered wireless detection system can realize long-term maintenance-free monitoring of ammonia leakage during ocean voyages," said Prof. FENG. "It is expected to play an important role in the further application and promotion of ammonia energy." (Text by WANG Zhenming)
　　

　　A research group led by Prof. PIAO Hailong from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. XU Guowang from DICP and Prof. TAN Guang from the First Affiliated Hospital of Dalian Medical University, identified the correlation between deubiquitinase ubiquitin-specific protease 22 (USP22) and abnormal lipidome accumulation in hepatocellular carcinoma (HCC).
　　They elucidated a USP22-regulated lipogenesis mechanism that involved the peroxisome proliferator-activated receptor gamma (PPARγ) - ATP citrate lyase (ACLY) / acetyl-CoA carboxylase (ACC) axis in HCC tumorigenesis, and provided a rationale for therapeutic targeting of lipogenesis via USP22 inhibition.
　　This study was published in Nature Communications on April 21.
　　PPARγ is stabilized by USP22-mediated deubiquitination leading to lipid accumulation and promoting hepatocellular carcinoma (Image by NING Zhen)
　　Metabolic reprogramming is one hallmark of cancer, among which the abnormally increased de novo lipogenesis (DNL) is one of the most common features.
　　Fatty acid synthesis occurs at a lower rate in nondividing cells, which mainly absorbs lipids from the extracellular circulation. In contrast, DNL, especially de novo fatty acid synthesis, is an important lipid source for cancer cells.
　　In this study, the researchers detected the expression of USP family members by immunoblotting in HCC tissues compared to paired normal adjacent tissues. They further screened different metabolites using liquid chromatography–mass spectrometry.
　　The results showed USP22 was the most significantly high expressed USP member, and this high expression of USP22 was correlated with lipids and lipid-like metabolites upregulation.
　　Molecular and biochemical experiments confirmed USP22 regulated lipid metabolism through PPARγ, a ligand-activated transcription factor belonging to the nuclear hormone receptor family that promoted lipogenesis by upregulating lipid synthesis enzymes such as ACC, ACLY and fatty acid synthase (FASN).
　　PPARγ was the substrate of USP22 and USP22-mediated deubiquitination stabilized PPARγ and activated PPARγ target genes (i.e., ACC and ACLY), contributing to lipogenesis and HCC tumorigenesis.
　　"This study provides an option for targeting fatty acid synthesis, which may benefit patients with high USP22 expression in HCC," said Prof. PIAO. (Text by LIU Xiaolong)

In the past decade, advances in synthetic biology paved the way toward the sustainable synthesis of complex natural products.The baking yeast Saccharomyces cerevisiae has been widely used in food industry and has become one of the main platforms for building cell factories due to its robustness, convenient cellular engineering, and reliable safety.Recently, a research group led by Prof. ZHOU Yongjin from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. ZHANG Lei from Naval Medical University, has developed efficient cofactor engineering strategies to derive phenolic acid biosynthesis in yeast.This study was published in Nature Chemical Biology on April 28.The cofactor metabolism is tightly regulated and complicatedly distributed in sub-organelles in eukaryotic cell such as yeast. Thus, it requires novel and feasible engineering strategies to cope with the complex cofactor regulation.The researchers developed tailored engineering strategies to enhance the supply, re-localization, and recycling of cofactors NADPH, FAD(H2), and SAM, which enabled high-level production of caffeic acid (5.5 g/L) and ferulic acid (3.8 g/L)."This work reveals the regulation of different cofactors in yeast, especially the distribution of cofactors between different organelles in cells, and provides theoretical guidance for cofactor engineering," said Prof. ZHOU. "It also provides sufficient precursors for the efficient synthesis of complex active natural products."The study was supported by the National Key Research and Development Program of China, the National Natural Science Foundation of China, the Liaoning Revitalization Talents Program, and the Innovation Grant from DICP. (CHEN Ruibing) 

　　Graphene-based micro-supercapacitors (EG-MSCs) can fully combine the distinct properties of graphene and the advantages of planar device configuration to maximize charge storage, thereby providing more flexible, smaller, and thinner devices.
　　However, the limited electric double layer capacity of graphene and the narrow voltage window of aqueous electrolytes limit its further application.
　　Recently, a team led by Prof. WU Zhongshuai collaborated with Prof. FU Qiang's team from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) proposed a versatile strategy for boosting the capacitance of graphene-based planar MSCs by highly concentrated water-in-salt ambipolar redox electrolyte (ZnI2 + ZnCl2).
　　This study was published in ACS Energy Letters on April 19.
　　Utilizing redox-active electrolytes for boosting graphene electrodes is a high-efficiency strategy to increase the capacitive performance of MSCs.
　　However, previously reported redox mediators could only offer a certain capacitance for a single electrode. The asymmetric behavior of the device could be aggravated by the enhanced capacitance of a single electrode, generally leading to limited energy density owing to the unmatched capacitances of two electrodes.
　　In this study, the researchers developed a novel highly concentrated water-in-salt ambipolar redox electrolyte where one ambipolar mediator (ZnI2) could offer two redox couples (I-/I2 and Zn/Zn2+) natively, with matched charge storage. Further, these two species allowed two electrons to be oxidized at the positive electrode and to be reduced at the negative electrode synchronously and individually, thus offering a large pseudocapacitive contribution for EG-MSCs.
　　They have realized the high volumetric capacity of 106 mAh/cm3, the unprecedented energy density of 111 mWh/cm3, and the long-term cycling stability with 92.1% retention after 5300 cycles.
　　In situ characterizations confirmed that these good performance were attributed to the frustrated self-discharge by suppressing the formation and diffusion of polyiodide ions of I3- and I5-.
　　Moreover, EG-MSCs showed stable cycling performance at -20 oC owing to the reduced freezing point of water by strong interactions between water molecules and zinc ions.
　　"This work opens a new avenue of introducing ambipolar redox mediators into highly concentrated electrolytes for high-performance MSCs," said Prof. WU.
　　This work was supported by the National Natural Science Foundation of China, the Dalian National Laboratory for Clean Energy of CAS, and the Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy. (Text by MENG Caixia and ZHOU Feng)

　　High-temperature polymer electrolyte membrane fuel cell (HT-PEMFC) can be applied in electric vehicles and marine power supplies.
　　However, the electrolyte in the HT-PEMFC is concentrated phosphoric acid, which electro-migrates from the cathode to the anode during fuel cell operation, leading to phosphoric acid redistribution and thereby affecting the multiphase mass transfer and electrochemical reaction inside the fuel cell.
　　Recently, a research group led by Prof. SUN Gongquan and Prof. WANG Suli from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) developed a novel multicomponent multiphase model to predict the distribution of phosphoric acid and water in HT-PEMFC, which can help to better understand the effects of materials, structures, and operating conditions on the multiphase transport of water and phosphoric acid.
　　This study was published in AIChE Journal on April 9.
　　Schematic of the cathode catalyst layer based on the agglomerate assumption (Image by SUN Mu)
　　The researchers explored the transport mechanism of water and phosphoric acid inside the HT-PEMFC and its impact on fuel cell performance by constructing a three-dimensional, non-isothermal, multiphase HT-PEMFC model based on a catalytic layer spherical agglomerate sub-model.
　　This model could predict the performance of the fuel cell. It included multicomponent multiphase transport of phosphoric acid and water model, and the energy transport model.
　　The simulation results showed that the phosphoric acid concentration in the anode was higher than that in the cathode, and about 20% of the water generated from the cathode diffuses to the anode in the form of the liquid phase.
　　"This study provides a theoretical basis for the optimization of the design of materials, structure, and operating conditions," said Prof. SUN.
　　The above work was supported by DICP, the National Natural Science Foundation of China, and CAS. (Text by SUN Mu)

　　A research team led by Prof. YANG Weishen and Prof. ZHU Xuefeng from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) has revealed the mechanism of oxygen activation on Barium-containing perovskite materials.
　　The researchers discovered that BaO/BaO2 nanoparticles precipitated on the surface of Ba-containing materials under high-temperature oxygen-rich conditions had an ultra-high activity for oxygen activation, which clarified the mechanism of high-temperature oxygen activation and transport on the surface of Ba-containing perovskite oxides.
　　This study was published on Science Advances on April 13.
　　Oxygen activation mechanism on Ba-containing perovskite oxides (Image by ZHU Yue)
　　In 2000, the DICP team invented an oxygen-permeable membrane material named Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF). Due to its good catalytic activity towards oxygen activation, BSCF has become a representative material for oxygen permeation and has been widely used in solid oxide fuel cells, oxygen reduction reactions, and oxygen evolution reactions.
　　However, the essence of the good performance of the BSCF perovskite is still unclear.
　　In this study, the researchers analyzed the oxygen permeation process and found that the addition of Ba into perovskite oxides could accelerate the oxygen surface exchange reaction kinetics.
　　They identified the precipitation of BaOx nanoparticles on the surface of BSCF materials in a high-temperature oxygen atmosphere by environmental electron microscopy, and proved that Ba-containing materials could be precipitated or decomposed into BaOx have high catalytic activity for the oxygen activation process.
　　Moreover, combined with DFT calculation, they found that the precipitated BaOx nanoparticles could reduce the energy barriers of oxygen molecule adsorption and dissociation in the oxygen reduction process and oxygen desorption process, thus accelerating the oxygen exchange reaction kinetics at the gas-solid interface.
　　"This study provides a scientific basis for the design of oxygen-permeable membranes and electrocatalytic materials," said Prof. YANG.
　　The above work was supported by the Pilot Project of CAS, the National Natural Science Foundation of China, and the China Postdoctoral Foundation. (Text by ZHU Yue)