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Journal of Iron and Steel Research International 2024年第4期31卷 945-955页

作者： Yuan Zhang Xiang liu chang-jun Wang chang liu School of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Central Iron&Steel Research Institute Co. Ltd.Beijing 100081China

PH13-8Mo stainless steel powder with high sphericity and well fluidity was prepared by the plasma rotating electrode *** formed parts with ultra-high purity were manufactured by selective laser *** tensile and impact mechanical properties of the printed parts under three heat treatment regimes were compared to those without heat *** microstructure,grain orientation and phase composition were characterized by electron-backscatter diffraction,X-ray diffraction and transmission electron *** characterization results reveal that the addition of heat treatment makes the grains enlarge,and after different heat treatments,the average grain size from 1.51μm in the printed state increases to 2.78,3.09 and 2.06μm,*** formed parts are mainly composed of martensite and retained ***,the NiAl and M23C precipitates form,which are the major strengthening phases of PH13-8Mo stainless *** optimal heat treatment process is 925℃×1 h water cooling(WC)+0℃×2 h air cooling(AC)+540℃×4 h *** this heat treatment process,PH13-8Mo formed parts have the optimal comprehensive mechanical properties:the tensile strength,yield strength and impact energy KU2 are 1492 MPa,1432 MPa and 63 J,*** strengthening and toughening via heat treatment are mainly attributed to dislocation strengthening,the formation of NiAl and M23Co precipitates and the change of volume fraction of the retained austenite.

关键词： High-strength stainless steel-Selective laser melting-Heat treatment Microstructure Mechanical property

Does the transformation of energy structure promote green technological innovation?A quasi-natural experiment based on new energy demonstration city construction

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Geoscience Frontiers 2024年第3期15卷 373-388页

作者： Chuanming liu chang Tang Yiding liu School of Economics Shandong University of Finance and EconomicsJinan 250014China School of Economics&Management Changsha University of Science and TechnologyChangsha 410076China School of Economic and Management Southeast UniversityNanjing 211189China

New energy development is essential to achieving carbon peaks and neutrality and promoting green technological *** the causal relationship between new energy demonstration city construction and green technological innovation is crucial for the expansion and promotion of new energy demonstration *** this study,we take the construction of new energy demonstration cities as a quasi-natural experiment,study their impact on green technological innovation using difference-indifference(DID),and conduct a robustness test using DID after propensity score matching(PSM-DID).The research results indicate the following:First,energy structure optimization can significantly improve the level of urban green technological innovation(this result was shown to be valid using PSM-DID and other tests involving the effects of placebo and instrumental variables).Second,new energy demonstration city construction mainly improves the level of urban green technological innovation through technology research and development,the improvement of the industrial innovation environment,and the promotion of environmental ***,the impact of energy structure optimization on green technological innovation has regional,financial,and economic development ***,new energy demonstration city policy affects the flow of capital,labor,technology,and other production factors to pilot areas according to new energy demonstration city policy,forming a“siphon effect”.The carbon reduction effect of new energy demonstration city construction is greater than its pollution reduction *** the results of the study,policy recommendations to promote the expansion of new energy demonstration cities are proposed.

关键词： New energy demonstration city Green technological innovation Theoretical mechanism Difference-in-difference

Input-to-State Stability of Impulsive Switched Systems Involving Uncertain Impulse-Switching Moments

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1515-1517页

作者： chang liu Wenlu liu Tengda Wei Xiaodi Li School of Mathematical and Statistics Shandong Normal UniversityJinan 250014China

Dear Editor,This letter studies the input-to-state stability(ISS)for a class of impulsive switched systems,where uncertain impulse-switching moments are *** robustness of ISS with respect to the perturbations of the occurrence time of impulse-switching moments is revealed by several less conservative dwell-time conditions for the uncertain impulse-switching moments combined with Lyapunov ***,the Lyapunov conditions have multiple coefficients at discrete time so as to handle the hybrid effect of impulse-switching moments,and the case that time derivative of Lyapunov function is indefinite is also taken into ***,a numerical example is proposed to illustrate the effectiveness of the theoretical results.

关键词： letter conservative derivative

Surfactant protein D inhibits lipid-laden foamy macrophages and lung inflammation in chronic obstructive pulmonary disease

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Cellular & Molecular Immunology 2023年第1期20卷 38-50页

作者： Miao-Hsi Hsieh Pei-Chi Chen Han-Yin Hsu jui-chang liu Yu-Sheng Ho Yuh Jyh Lin Chin-Wei Kuo Wen-Shuo Kuo Hui-Fang Kao Shulhn-Der Wang Zhi-Gang liu Lawrence Shih-Hsin Wu Jiu-Yao Wang Center for Allergy Immunologyand Microbiome(A.I.M.)China Medical University HospitalTaichungTaiwanChina Graduate Institute of Basic Medical Sciences College of MedicineNational Cheng Kung UniversityTainanTaiwanChina Department of Nursing National Tainan Junior College of NursingTainanTaiwanChina Graduate Institute of Biochemistry and Molecular Biology College of MedicineNational Cheng Kung UniversityTainanTaiwanChina Department of Pediatrics National Cheng Kung University HospitalTainanTaiwanChina Division of Pulmonary Medicine Department of Internal MedicineNational Cheng Kung University HospitalCollege of MedicineNational Cheng Kung UniversityTainanTaiwanChina Institute of Clinical Medicine College of MedicineNational Cheng Kung UniversityTainanTaiwanChina School of Chemistry and Materials Science Nanjing University of Information Science and TechnologyNanjingChina School of Post-Baccalaureate Chinese Medicine China Medical UniversityTaichungTaiwanChina Department of Respirology and Allergy Third Affiliated Hospital of Shenzhen UniversityShenzhenChina Institute of Biomedical Sciences China Medical UniversityTaichungTaiwanChina Department of Allergy Immunologyand Rheumatology(AIR)China Medical University Children’s HospitalTaichungTaiwanChina

Increased levels of surfactant protein D (SP-D) and lipid-laden foamy macrophages (FMs) are frequently found under oxidative stress conditions and/or in patients with chronic obstructive pulmonary disease (COPD) who are also chronically exposed to cigarette smoke (CS). However, the roles and molecular mechanisms of SP-D and FMs in COPD have not yet been determined. In this study, increased levels of SP-D were found in the bronchoalveolar lavage fluid (BALF) and sera of ozone- and CS-exposed mice. Furthermore, SP-D-knockout mice showed increased lipid-laden FMs and airway inflammation caused by ozone and CS exposure, similar to that exhibited by our study cohort of chronic smokers and COPD patients. We also showed that an exogenous recombinant fragment of human SP-D (rfhSP-D) prevented the formation of oxidized low-density lipoprotein (oxLDL)-induced FMs in vitro and reversed the airway inflammation and emphysematous changes caused by oxidative stress and CS exposure in vivo. SP-D upregulated bone marrow-derived macrophage (BMDM) expression of genes involved in countering the oxidative stress and lipid metabolism perturbations induced by CS and oxLDL. Our study demonstrates the crucial roles of SP-D in the lipid homeostasis of dysfunctional alveolar macrophages caused by ozone and CS exposure in experimental mouse emphysema, which may provide a novel opportunity for the clinical application of SP-D in patients with COPD.

关键词： Alveolar macrophages Chronic obstructive pulmonary diseases Surfactant protein D Lipid metabolism Ozone Cigarettes

Scattering-based hybrid network for facial attribute classification

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Frontiers of Computer Science 2024年第3期18卷 105-116页

作者： Na liu Fan ZHANG Liang chang Fuqing DUAN School of Artificial Intelligence Beijing Normal UniversityBeijing 100875China

Face attribute classification(FAC)is a high-profile problem in biometric verification and face *** recent research has been devoted to extracting more delicate image attribute features and exploiting the inter-attribute correlations,significant challenges still *** scattering transform(WST)is a promising non-learned feature *** has been shown to yield more discriminative representations and outperforms the learned representations in certain *** to the image classification task,WST can enhance subtle image texture information and create local deformation *** paper designs a scattering-based hybrid block,to incorporate frequency-domain(WST)and image-domain features in a channel attention manner(Squeezeand-Excitation,SE),termed WS-SE *** with CNN,WS-SE achieves a more efficient FAC performance and compensates for the model sensitivity of the small-scale affine *** addition,to further exploit the relationships among the attribute labels,we propose a learning strategy from a causal *** cause attributes defined using the causalityrelated information can be utilized to infer the effect attributes with a high confidence *** analysis experiments demonstrate the effectiveness of our model,and our hybrid model obtains state-of-the-art results in two public datasets.

关键词： wavelet scattering transform causality-related learning facial attribute classification

Effect of tubastatin A on NLRP3 inflammasome activation in macrophages under hypoxia/ reoxygenation conditions

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World Journal of Emergency Medicine 2024年第4期15卷 289-296页

作者： Hao Li chang liu Ying Cui Panpan chang Wei Chong Department of Emergency Medicine the First Hospital of China Medical UniversityShenyang 110001China Trauma Medicine Center Peking University People's HospitalBeijing 100871China Key Laboratory of Trauma and Neural Regeneration Peking UniversityBeijing 100871China National Center for Trauma Medicine of China Beijing 100871China

BACKGROUND:There are currently no effective drugs to mitigate the ischemia/reperfusion injury caused by fluid resuscitation after hemorrhagic shock(HS).The aim of this study was to explore the potential of the histone deacetylase 6(HDAC6)-specific inhibitor tubastatin A(TubA)to suppress nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3)inflammasome activation in macrophages under hypoxia/reoxygenation(H/R)***:The viability of RAW264.7 cells subjected to H/R after treatment with different concentrations of TubA was assessed using a cell-counting kit-8(CCK8)***,2.5μmol/L TubA was used with RAW264.7 cells under H/R ***264.7 cells were divided into three groups,namely the control,H/R,and TubA *** levels of reactive oxygen species(ROS)in the cells were detected using fluorescence *** protein expression of HDAC6,heat shock protein 90(Hsp90),inducible nitric oxide synthase(iNOS),NLRP3,gasdermin-D(GSDMD),Caspase-1,GSDMD-N,and Caspase-1 p20 was detected by western *** levels of interleukin-1β(IL-1β)and IL-18 in the supernatants were detected using enzyme-linked immunosorbent assay(ELISA).RESULTS:HDAC6,Hsp90,and iNOS expression levels were significantly higher(P<0.01)in the H/R group than in the control group,but lower in the TubA group than in the H/R group(P<0.05).When comparing the H/R group to the control group,ROS levels were significantly higher(P<0.01),but significantly reduced in the TubA group(P<0.05).The H/R group had higher NLRP3,GSDMD,Caspase-1,GSDMD-N,and Caspase-1 p20 expression levels than the control group(P<0.05),however,the TubA group had significantly lower expression levels than the H/R group(P<0.05).IL-1βand IL-18 levels in the supernatants were significantly higher in the H/R group compared to the control group(P<0.01),but significantly lower in the TubA group compared to the H/R group(P<0.01).CONCLUSION:TubA inhibited the expression of HDAC6,Hsp90,and iNOS in macrophages

关键词： Hemorrhagic shock Hypoxia/reoxygenation Macrophage NLRP3 Tubastatin A

Gut microbial interactions based on network construction and bacterial pairwise cultivation

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Science China(Life Sciences) 2024年第8期67卷 1751-1762页

作者： Min-Zhi Jiang chang liu chang Xu He Jiang Yulin Wang Shuang-Jiang liu State Key Laboratory of Microbial Technology Shandong UniversityQingdao 266000China State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center(EMRC)Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Association networks are widely applied for the prediction of bacterial interactions in studies of human gut ***,the experimental validation of the predicted interactions is challenging due to the complexity of gut microbiomes and the limited number of cultivated *** this study,we addressed this challenge by integrating in vitro time series network(TSN)associations and cocultivation of TSN taxon *** samples were collected and used for cultivation and enrichment of gut microbiome on YCFA agar plates for 13 *** cells were harvested for DNA extraction and metagenomic sequencing.A total of 198 metagenome-assembled genomes(MAGs)were *** dynamics of bacteria growing on the YCFA agar were used to infer microbial association *** experimentally validate the interactions of taxon pairs in networks,we selected 24 and 19 bacterial strains from this study and from the previously established human gut microbial biobank,respectively,for pairwise *** co-culture experiments revealed that most of the interactions between taxa in networks were identified as neutralism(51.67%),followed by commensalism(21.67%),amensalism(18.33%),competition(5%)and exploitation(3.33%).Genome-centric analysis further revealed that the commensal gut bacteria(helpers and beneficiaries)might interact with each other via the exchanges of amino acids with high biosynthetic costs,short-chain fatty acids,and/or *** also validated 12 beneficiaries by adding 16 additives into the basic YCFA medium and found that the growth of 66.7%of these strains was significantly *** approach provides new insights into the gut microbiome complexity and microbial interactions in association *** work highlights that the positive relationships in gut microbial communities tend to be overestimated,and that amino acids,short-chain fatty acids,and vitamins are contributed to the positive relationships.

关键词： human gut microbiome gut microbial pairwise interaction co-culture association network microbial community

Pt nanodendrites with a PtIr alloy surface structure exhibit excellent stability toward acidic hydrogen evolution reaction

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Nano Research 2024年第6期17卷 4844-4849页

作者： chang liu Zongnan Wei Minna Cao Rong Cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

The development of effective and stable electrocatalysts for the hydrogen evolution reaction(HER)in acidic electrolytes is a significant *** this work,homogeneous Pt nanodendrites(Pt NDs)with a PtIr shell were successfully synthesized by a two-step wet chemical *** open three-dimensional(3D)dendritic structure exhibited exceptional electrocatalytic characteristics,exposing as many active sites as ***,by alloying Ir with Pt on the surface,catalytic activity was greatly enhanced while ensuring extremely high *** surface-enriched platinum nanodendritic catalysts(Pt@PtIr NDs)outperformed the control samples and the commercial *** acidic HER test,Pt@PtIr NDs had a lower overpotential(22 mV)than Pt NDs(26 mV)and commercial Pt/C(31 mV)at 10 mA/cm^(2),and the activity of Pt@PtIr NDs remained consistent even after undergoing a continuous durability test for at least 168 h,which was much superior to the performance of commercial Pt/C(10 h)under identical test *** study revealed that the application of 3D Pt dendritic metal alloys may offer a chance for the development of enhanced electrocatalysts in acidic HER.

关键词： Pt nanodendrites iridium high stability hydrogen evolution reaction alloy

Intrinsic pentagon defect engineering in multiple spatial-scale carbon frameworks for efficient triiodide reduction

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Journal of Energy Chemistry 2024年第8期95卷 20-28,I0002页

作者： Siyi Hou Xuedan Song chang Yu Jiangwei chang Yiwang Ding Yingbin liu Xiubo Zhang Weizhe liu Jieshan Qiu State Key Lab of Fine Chemicals Liaoning Key Lab for Energy Materials and Chemical EngineeringFrontier Science Center for Smart MaterialsSchool of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina Liaoning Key Lab for Energy Materials and Chemical Engineering Frontier Science Center for Smart MaterialsSchool of ChemistryDalian University of TechnologyDalian 116024LiaoningChina State Key Laboratory of Chemical Resource Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Intrinsic topological defect engineering has been proven as a promising strategy to elevate the electrocatalytic activity of carbon ***,the controllable construction of high-density and specific topological defects in carbon frameworks to reveal the relationship between reactivity and defect structure remains a challenging ***,the intrinsic pentagon carbon sites that can favor electron overflow and enhance their binding affinity towards the intermediates of catalytic reaction are firstly presented by the work function and the p-band center *** experimentally verify this,the cage-opening reaction of fullerene is proposed and utilized for synthesizing carbon quantum dots with specific pentagon configuration(CQDs-P),subsequently utilizing CQDs-P to modulate the micro-scale defect density of three-dimensional reduced graphene oxide(rGO)viaπ-π*** multiple spatial-scale rGO-conjugated CQDs-P structure simultaneously possesses abundant pentagon and edge defects as catalytic active sites and long-range-orderedπelectron delocalization system as conductive *** defects-rich CQDs-P/rGO-4 all-carbon-based catalyst exhibits superb catalytic activity for triiodide reduction reaction with a high photoelectric conversion efficiency of 8.40%,superior to the Pt reference(7.97%).Theoretical calculations suggest that pentagon defects in the carbon frameworks can promote charge transfer and modulate the adsorption/dissociation behavior of the reaction intermediates,thus enhancing the electrocatalytic activity of the *** work confirms the role of intrinsic pentagon defects in catalytic reactions and provides a new insight into the synthesis of defects-rich carbon catalysts.

关键词： Defect engineering Pentagon carbon Carbon quantum dots Electrocatalytic activity Triiodide reduction

Dislocation density-me diate d creep ageing behavior of an Al-Cu-Li alloy

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Journal of Materials Science & Technology 2024年第7期174卷 204-217页

作者： chang Zhou Lihua Zhan Chunhui liu Minghui Huang College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South UniversityChangsha 410083China Light Alloys Research Institute Central South UniversityChangsha 410083China

Creep aging is well-known to be a time-dependent,coupled process of deformation and precipitation strengthening for age-hardening *** existing mechanisms are mainly attributed to those interac-tions between atomic diffusion and dislocation ***,an understanding of the relationship between dislocation density and a special multistage creep behavior,i.e.,double steady creep feature,is still far *** we investigate the effect of various dislocation density levels on such an abnormal multistage creep of an Al-Cu-Li *** find that the increased dislocation densities enable an apparent time decrease(from 6.2 h to 0.8 h)of their first steadyⅡ-*** yield strength of post-aged sam-ples increases from 425.0 MPa to 580.0 MPa while the corresponding elongation decreases from 12.3%to 7.3%for the creep-aged samples#1 to#*** results also reveal that a great difference in dislocation configuration,tailored by various density levels,results in varying creep processes of theⅡ-*** stage is closely related to the nucleation and early growth of T_(1)*** number densities(maximum:2.9×10^(19)m^(-3))and the average length(maximum:21.3 nm)of T_(1)precipitates are much smaller than those of the stable peak-aged T_(1)phases,suggesting that creepⅡ-stage of all three creep-aged samples is dominant by the nucleation and initial growth of those T_(1)*** study provides valuable insights into the dislocation density-mediated creep deformation of an Al-Cu-Li alloy.

关键词： Dislocation density Al-Cu-Li alloy Creep ageing T_(1)precipitation