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Chinese Journal of Chemical Engineering 2022年第3期35卷 161-168页

作者： Jun Chen Liandong Li Liu Yang Chang chen Shitao Wang Yan Huang Dapeng Cao State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

Developing high efficient bifunctional oxygen electrocatalysts for clean energy applications like Zin-air battery(ZAB)is highly desired,because it would reduce the cost and speed up the practical application of ZAB.Here we use a dual metal-organic framework(MOF)synthesis strategy to prepare the N-doped carbon supported bimetallic FeCo nanoparticle catalysts(marked as FeCo@NC)by pyrolysis of Zn CoZIF/MIL-101(Fe)composite.The FeCo@NC exhibits remarkable electrocatalytic activity for ORR with half-wave potential of 0.89 V vs.the reversible hydrogen electrode(RHE)and robust durability for both ORR and OER(oxygen reduction reaction and oxygen evolution reaction),which is attributed to the generation of Fe_(0.26)Co_(0.74) crystalline phase and mesopores due to the dual-MOF synthesis strategy.The rechargeable ZAB based on FeCo@NC air electrode shows a maximum energy density of139.6 mW·cm^(-2) and excellent cyclic stability over 130 h,significantly surpassing the Pt and Ir-based ZAB.The present work provides a useful dual-MOF synthesis strategy for preparing high-performance multifunctional catalysts for ORR,OER and hydrogen evolution reaction(HER).

关键词： Metal Organic Frameworks Zeolite imidazole framework Bifunctional electrocatalysts FeCo alloy Zn-air battery

Ribosome biogenesis gene DEF/UTP25 is essential for liver homeostasis and regeneration

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Science China(Life Sciences) 2020年第11期63卷 1651-1664页

作者： Weidong Huang Feng chen Quanxin Ma Jiaojiao Xin Jiaqi Li Jun Chen Bin Zhou Minli chen jun Li Jinrong Peng MOE Key Laboratory of Molecular Animal Nutrition College of Animal SciencesZhejiang UniversityHangzhou 310058China Academy of Chinese Medicine/Institute of Comparative Medicine Zhejiang Chinese Medical UniversityHangzhou 310053China State Key Laboratory for Diagnosis and Treatment of Infectious Diseases Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310003China College of Life Sciences Zhejiang UniversityHangzhou 310058China The State Key Laboratory of Cell Biology CAS Center for Excellence on Molecular Cell ScienceShanghai Institute of Biochemistry and Cell BiologyUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200031China

Hepatocytes are responsible for diverse metabolic activities in a liver. Proper ribosome biogenesis is essential to sustain the function of hepatocytes. There are approximately 200 factors involved in ribosome biogenesis;however, few studies have focused on the role of these factors in maintaining liver homeostasis. The digestive organ expansion factor(def) gene encodes a nucleolar protein Def that participates in ribosome biogenesis. In addition, Def forms a complex with cysteine protease Calpain3(Capn3) and recruits Capn3 to the nucleolus to cleave protein targets. However, the function of Def has not been characterized in the mammalian digestive organs. In this report, we show that conditional knockout of the mouse def gene in hepatocytes causes cell morphology abnormality and constant infiltration of inflammatory cells in the liver. As age increases, the def conditional knockout liver displays multiple tissue damage foci and biliary hyperplasia. Moreover, partial hepatectomy leads to sudden acute death to the def conditional knockout mice and this phenotype is rescued by intragastric injection of the anti-inflammation drug dexamethasone one day before hepatectomy. Our results demonstrate that Def is essential for maintaining the liver homeostasis and liver regeneration capacity in mammals.

关键词： homeostasis organs inflammation

Microstructure and mechanical properties of Mg-Gd-Y-Sm-Al alloy and analysis of grain refinement and strengthening mechanism

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Journal of Rare Earths 2019年第12期37卷 1351-1358页

作者： Xiaoya chen Quanan Li Jun Chen Limin Zhu School of Materials Science and Engineering Xi'an University of TechnologyXi'an 740048China School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China Collaborative Innovation Center of Nonferrous Metals Henan ProvinceLuoyang 471023China

The effects of Sm on the microstructure and mechanical properties of Mg-11 Gd-2 Y-0.6 Al alloy were investigated by X-ray diffraction,optical microscopy,scanning electron microscopy,energy dispersive spectrometry and high resolution transmission electron microscopy.Based on the theory of edge—edge matching and electronegativity theory,the mechanism of grain refinement is discussed.The strengthening mechanism is expounded conveniently from fine grain strengthening,coherent strengthening,precipitation strengthening and grain boundary strengthening.The results show that the micro structure of Mg-11 Gd-2 Y-0.6 Al alloy is mainly composed of a-Mg matrix,Mg5 Gd and Mg24Y5 phases.The addition of Sm forms Mg41Sm5 phase in the alloy and refines the alloy.The addition of Sm significantly improves the mechanical properties of the alloy at room and high temperatures.When the addition of Sm is 3 wt%,the tensile strengths of the alloy at room temperature and high temperature(200℃)reach the maximum value 292 and 321 MPa,respectively.The fracture mode of the alloy at different temperatures is mainly brittle fracture and intercrystalline fracture.

关键词： Mg-11Gd-2Y-0.6Al alloy Micro structure Mechanical property Grain refinement Strengthening mechanism Rare earths

Toward accurate and efficient dynamic computational strategy for heterogeneous catalysis:Temperature-dependent thermodynamics and kinetics for the chemisorbed on-surface CO

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Chinese Chemical Letters 2022年第11期33卷 4936-4942页

作者： Jun Chen Tan Jin Yihuang Jiang Tonghao Shen Mingjun Yang Zhe-Ning chen Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China State Key Laboratory of Physical Chemistry of Solid Surfaces Fujian Provincial Key Laboratory of Theoretical and Computational ChemistryXiamen UniversityXiamen 361005China University of Chinese Academy of Sciences Beijing 100049China MOE Key Laboratory of Computational Physical Sciences Department of ChemistryFudan UniversityShanghai 200433China Shenzhen Jingtai Technology Co. Ltd.(XtalPi)Fubao CommunityShenzhen 518045China

Computational tools on top of first principle calculations have played an indispensable role in revealing the molecular details,thermodynamics,and kinetics in catalytic reactions.Here we proposed a highly efficient dynamic strategy for the calculation of thermodynamic and kinetic properties in heterogeneous catalysis on the basis of efficient potential energy surface(PES)and MD simulations.Taking CO adsorbate on Ru(0001)surface as the illustrative model system,we demonstrated the PES-based MD can efficiently generate reliable two-dimensional potential-of-mean-force(PMF)surfaces in a wide range of temperatures,and thus temperature-dependent thermodynamic properties can be obtained in a comprehensive investigation on the whole PMF surface.Moreover,MD offers an effective way to describe the surface kinetics such as adsorbate on-surface movement,which goes beyond the most popular static approach based on free energy barrier and transition state theory(TST).We further revealed that the dynamic strategy significantly improves the predictions of both thermodynamic and kinetic properties as compared to the popular ideal statistic mechanics approaches such as harmonic analysis and TST.It is expected that this accurate yet efficient dynamic strategy can be powerful in understanding mechanisms and reactivity of a catalytic surface system,and further guides the rational design of heterogeneous catalysts.

关键词： Dynamic strategy Temperature-dependent thermodynamics Statistical sampling Neural networks potential energy surface Operando simulation

The role of lipids in fermentative propionate production from the co-fermentation of lipid and food waste

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Frontiers of Environmental Science & Engineering 2023年第7期17卷 107-118页

作者： Niyou Xu Ting chen jun Yin School of Environmental Science and Engineering Zhejiang Gongshang UniversityHangzhou 310012China Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling Hangzhou 310012China

Food waste(FW)is a promising renewable low-cost biomass substrate for enhancing the economic feasibility of fermentative propionate production.Although lipids,a common component of food waste,can be used as a carbon source to enhance the production of volatile fatty acids(VFAs)during co-fermentation,few studies have evaluated the potential for directional propionate production from the co-fermentation of lipids and FW.In this study,co-fermentation experiments were conducted using different combinations of lipids and FW for VFA production.The contributions of lipids and FW to propionate production,hydrolysis of substrates,and microbial composition during.cofermentation were evaluated.The results revealed that lipids shifted the fermentation type of FW from butyric to propionic acid fermentation.Based on the estimated propionate production kinetic parameters,the maximum propionate productivity increased significantly with an increase in lipid content,reaching 6.23 g propionate/(L·d)at a lipid content of 50%.Propionate-producing bacteria Prevotella,Veillonella,and norank f Propionibacteriaceae were enriched in the presence of lipids,and the succinate pathway was identified as a prominent fermentation route for propionate production.Moreover,the Kyoto Encyclopedia of Genes and Genomes functional annotation revealed that the expression of functional genes associated with amino acid metabolism was enhanced by the presence of lipids.Collectively,these findings will contribute to gaining a better understanding of targeted propionate production from FW.

关键词： Acidogenic fermentation Microbial community Volatile fatty acid Propionate Foodwaste Lipid

Molecular Mechanism of Polysaccharides Extracted from Chinese Medicine Targeting Gut Microbiota for Promoting Health

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Chinese Journal of Integrative Medicine 2024年第2期30卷 171-180页

作者： ZHAO Wen-xiao WANG Tong ZHANG Ya-nan chen Qian WANG Yuan XING Yan-qing ZHENG jun DUAN chen-chen chen Lijun ZHAO Hai-jun WANG Shijun School of Nursing Shandong University of Traditional Chinese MedicineShandong University of Traditional Chinese MedicineJi'nan(250355)China Shandong Co-innovation Center of Classic Traditional Chinese Medicine Formula Shandong University of Traditional Chinese MedicineJi'nan(250355)China College of Traditional Chinese Medicine Shandong University of Traditional Chinese MedicineJinan(250355)China

The accumulating evidence revealed that gut microbiota plays an important role in pathological process of disease including obesity,type 2 diabetes mellitus,heart failure,and non-alcoholic fatty liver disease.Polysaccharides extracted from Chinese medicine(CM)can not only alleviate pathological status but also promote health by anti-inflammatory,regulating immunity,lowering blood glucose and lipids,anti-cancer,and anti-oxidation.The alterations of gut microbiota composition and metabolism pathways are the potential mechanisms of CM polysaccharides treatment.In addition,they exert functions through gut-organ axis or play an indirect role by synergistic actions with other drugs or components mediated by gut microbiota.This review summarizes the molecular mechanisms of CM polysaccharides interacted with intestinal microbial inhabitants as potential prebiotics forpromoting health.

关键词： Chinese medicine polysaccharides gut microbiota short-chain fatty acids lipopolysaccharides gut-organaxis synergistic actions

Resilience patterns of human mobility in response to extreme urban floods

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National Science Review 2023年第8期10卷 121-133页

作者： junqing Tang Pengjun Zhao Zhaoya Gong Hongbo Zhao Fengjue Huang Jiaying Li Zhihe chen Ling Yu Jun Chen School of Urban Planning and Design Shenzhen Graduate School Peking University 2. Key Laboratory of Earth Surface System and Human-Earth Relations of Ministry of Natural Resources of China Shenzhen Graduate SchoolPeking University School of Urban and Environmental Sciences Peking University Key Research Institute of Yellow River Civilization and Sustainable Development&Collaborative Innovation Center on Yellow River Civilization Henan Province and Ministry of Education Henan University 5. Key National Geomatics Center of China

Large-scale disasters can disproportionately impact different population groups, causing prominent disparity and inequality, especially for the vulnerable and marginalized. Here, we investigate the resilience of human mobility under the disturbance of the unprecedented ‘720’ Zhengzhou flood in China in 2021 using records of 1.32 billion mobile phone signaling generated by 4.35 million people. We find that although pluvial floods can trigger mobility reductions, the overall structural dynamics of mobility networks remain relatively stable. We also find that the low levels of mobility resilience in female, adolescent and older adult groups are mainly due to their insufficient capabilities to maintain business-as-usual travel frequency during the flood. Most importantly, we reveal three types of counter-intuitive, yet widely existing,resilience patterns of human mobility(namely, ‘reverse bathtub’, ‘ever-increasing’ and ‘ever-decreasing’ patterns), and demonstrate a universal mechanism of disaster-avoidance response by further corroborating that those abnormal resilience patterns are not associated with people’s gender or age. In view of the common association between travel behaviors and travelers’ socio-demographic characteristics, our findings provide a caveat for scholars when disclosing disparities in human travel behaviors during flood-induced emergencies.

关键词： disaster resilience urban flood human mobility Zhengzhou flood mobile phone data

Cdx1b protects intestinal cell fate by repressing signaling networks for liver specification

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Journal of Genetics and Genomics 2022年第12期49卷 1101-1113页

作者： Qingxia Jin Yuqi Gao Shimin Shuai Yayue chen Kaiyuan Wang Jun Chen Jinrong Peng Ce Gao College of Animal Sciences Zhejiang UniversityHangzhouZhejiang 310058China Department of Human Cell Biology and Genetics School of MedicineSouthern University of Science and TechnologyShenzhenGuangdong 518055China College of Life Sciences Zhejiang UniversityHangzhouZhejiang 310058China

In mammals,the expression of the homeobox family member Cdx2/CDX2 is restricted within the intestine.Conditional ablation of the mouse Cdx2 in the endodermal cells causes a homeotic transformation of the intestine towards the esophagus or gastric fate.In this report,we show that null mutants of zebrafish cdx1b,encoding the counterpart of mammalian CDX2,could survive more than 10 days post fertilization,a stage when the zebrafish digestive system has been well developed.Through RNA sequencing(RNA-seq)and single-cell sequencing(sc RNA-seq)of the dissected intestine from the mutant embryos,we demonstrate that the loss-of-function of the zebrafish cdx1b yields hepatocyte-like intestinal cells,a phenotype never observed in the mouse model.Further RNA-seq data analysis,and genetic double mutants and signaling inhibitor studies reveal that Cdx1b functions to guard the intestinal fate by repressing,directly or indirectly,a range of transcriptional factors and signaling pathways for liver specification.Finally,we demonstrate that heat shock-induced overexpression of cdx1b in a transgenic fish abolishes the liver formation.Therefore,we demonstrate that Cdx1b is a key repressor of hepatic fate during the intestine specification in zebrafish.

关键词： Cdx1b CDX2 Hhex Intestine development Liver development Prox1a Zebrafish

Structural characterization and immunostimulatory activity of a water-soluble polysaccharide from abalone(Haliotis discus hannai Ino)muscle

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Food Science and Human Wellness 2023年第2期12卷 495-502页

作者： Linfan Shi Gengxin Hao Jun Chen junling Wang Wuyin Weng College of Ocean Food and Biological Engineering Jimei UniversityXiamen 361021China Engineering Research Center of the Modern Technology for Eel Industry Ministry of EducationXiamen 361021China

A water-soluble polysaccharide from abalone muscle(AMPP)was isolated.The contents of carbohydrate,protein,uronic acid,and sulfate in AMPP were 83.5%,0.5%,2.7%,and 2.6%,respectively.High-performance liquid chromatography analysis indicated that AMPP was homogeneous and had an average molecular weight of approximately 3.2 kDa.The main monosaccharides of AMPP were glucose(Glc)and mannose with a molar ratio of 99.7:0.3.The structural characteristics of AMPP were elucidated through methylation analysis,Fourier transform infrared spectroscopy,and nuclear magnetic resonance spectroscopy.The linkages of AMPP consisted of terminal,1,4-linked,1,6-linked,and 1,4,6-linked Glcp with a molar ratio of 3.1:7.2:1.0:2.5.In one repeat unit of the proposed AMPP structure,the backbone chain was composed of eight 1→4 glycosidic bonds and one 1→6 glycosidic bond,with three branch chains linked by 1→6 glycosidic bond.In addition,AMPP was found to possess potent immunostimulatory activity via rising phagocytosis of RAW264.7 cells and promoting secretion of TNF-α.

关键词： Polysaccharide Abalone muscle Structural characterization Immunostimulatory activity Nuclear magnetic resonance spectra

Observation of the Hydrogen-Dislocation Interactions in a High-Manganese Steel after Hydrogen Adsorption and Desorption

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Acta Metallurgica Sinica(English Letters) 2023年第7期36卷 1105-1112页

作者： Dayong An Yuhao Zhou Yao Xiao Xinxi Liu Xifeng Li Jun Chen Department of Plasticity Technology School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200030China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China

Hydrogen embrittlement(HE)poses a significant challenge for the development of high-strength metallic materials.However,explanations for the observed HE phenomena are still under debate.To shed light on this issue,here we investigated the hydrogen-defect interaction by comparing the dislocation structure evolution after hydrogen adsorption and desorption in a Fe-28Mn-0.3C(wt%)twinning-induced plasticity steel with an austenitic structure using in situ electron channeling contrast imaging.The results indicate that hydrogen can strongly affect dislocation activities.In detail,hydrogen can promote the formation of stacking faults with a long dissociation distance.Besides,dislocation movements are frequently observed during hydrogen desorption.The required resolved shear stress is considered to be the residual stresses rendered by hydrogen segregation.Furthermore,the microstructural heterogeneity could lead to the discrepancy of dislocation activities even within the same materials.

关键词： Hydrogen embrittlement Stacking fault Dislocation movement High-manganese steel Electron channeling contrast imaging(ECCI)