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NiCo/Al_(2)O_(3)nanocatalysts for the synthesis of 5-amino-1-pentanol and 1,5-pentanediol from biomass-derived 2-hydroxytetrahydropyran

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Green Chemical Engineering 2024年第1期5卷 119-131页

作者： Jian Yang Jia Zhang Enrico Benassi Xuemei Li hailong Liu Weiguo Fang Junying Tian Chungu Xia Zhiwei Huang State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China School of Petrochemical Engineering Lanzhou University of TechnologyLanzhou730050China Novosibirsk State University Novosibirsk630090Russia University of Chinese Academy of Sciences Beijing100049China

Al_(2)O_(3)-supported monometallic Ni,Co,and bimetallic Ni-Co nanocatalysts originated from layered double hydroxide precursors were synthesized by co-precipitation method,and used for the synthesis of useful 5-amino-1-pentanol(5-AP)and 1,5-pentanediol(1,5-PD)by reductive amination(RA)or direct hydrogenation of biofurfuralderived 2-hydroxytetrahydropyran(2-HTHP),respectively.In both reactions,the yield of the target products decreased monotonously with the increasing amounts of Co in the NiCo/Al_(2)O_(3)catalysts,owing probably to the replacement of highly reactive Ni by Co component with inferior hydrogenation activity at the low reaction temperature of 60℃.However,the incorporation of Co could improve the reducibility of the NiCo/Al_(2)O_(3)bimetallic catalysts and promote the reaction stability of the catalysts,especially for Ni_(2)Co1/Al_(2)O_(3),in both reactions with over 180 h time-on-stream.Characterization of the catalysts before and after the reaction showed that the incorporating Co could inhibit the sintering of metal particles and hinder the surface oxidation of the more reactive Ni0species,thanks to the formation of Ni-Co alloy in the bimetallic catalysts.DFT-based modeling of the reaction mechanisms is also performed,supporting the reaction pathway proposed previously and also the much higher activity of Ni in the RA of 2-HTHP as compared with Co.

关键词： NiCo bimetallic catalysts Layered double hydroxide Reductive amination Amino alcohol Quantum chemical calculations

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Polystyrene nanoplastics induce glycolipid metabolism disorder via NF-κB and MAPK signaling pathway in mice

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Journal of Environmental Sciences 2024年第3期137卷 553-566页

作者： Xingpei Fan Xiaoyan Li Jiaxin Li Yuxia Zhang Xiangjuan Wei hailong Hu Boya Zhang Haining Du Meimei Zhao Ruijiao Zhu Daqian Yang Yuri Oh Ning Gu School of Life Science and Technology Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150006China Department of Medicine Renal Electrolyte and Hypertension DivisionDepartment of GeneticsPerelman School of MedicineUniversity of PennsylvaniaPhiladelphia 19104USA Faculty of Education Wakayama UniversityWakayama 640-8441Japan

Nanoplastics-induced developmental and reproductive toxicity,neurotoxicity and immunotoxicity are a focus of widespread attention.However,the effects of nanoplastics(NPs)on glycolipid metabolism and the precise underlying mechanisms are unclear at present.Here,we showed that oral administration of polystyrene nanoparticles(PS-NPs)disrupts glycolipid metabolism,with reactive oxygen species(ROS)identified as a potential key signaling molecule.After PS-NPs treatment,excessive production of ROS induced the infammatory response and activated the antioxidant pathway through nuclear factor-erythroid factor 2-related factor 2.The activation of nuclear factor-κB(NFκB)signaling pathway induced the phosphorylation of the mitogen-activated protein kinases(MAPK)signaling pathway,which induced the activation of extracellular regulated kinases(ERK)and p38.Constitutive activation of the MAPK signaling proteins induced high continued phosphorylation of insulin receptor substrate-1,in turn,leading to decreased protein kinase B(Akt)activity,which weakened the sensitivity of liver cells to insulin signals and induced insulin resistance.In parallel,phosphorylation of Akt led to loss of control of Fo XO1,a key gene of gluconeogenesis,activating transcription of glucose-6-phosphatase(G6PC)and phosphoenolpyruvate carboxykinase(PEPCK)in a manner dependent on PGC1α.Moreover,the activated ERK promoted lipid accumulation through ERK-PPARγcascades.Therefore,sterol regulatory element-binding protein-1 and levels of its downstream lipogenic enzymes,ACC-1,were up-regulated.Upon treatment with the antioxidant resveratrol,PS-NPs-induced glucose and lipid metabolic disorders were improved by inhibiting ROS-induced activation of NFκB and MAPK signaling pathway in mice.Based on above,PS-NPs exposure disrupts glycolipid metabolism in mice,with ROS identified as a potential key signaling molecule.

关键词： Nanoplastics Resveratrol Hyperglycemia Lipid metabolism Infammatory response Reactive oxygen species(ROS)

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PVDF/6H-SiC composite fiber films with enhanced piezoelectric performance by interfacial engineering for diversified applications

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Journal of Materials Science & Technology 2024年第3期170卷 238-245页

作者： Linlin Zhou Tao Yang Chunyu Guo Kang Wang Enhui Wang Laipan Zhu hailong Wang Sheng Cao Kuo-Chih Chou Xinmei Hou Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China School of Materials Science Engineering Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi UniversityNanning 530004China

Piezoelectric silicon carbide(SiC)has been quite attractive due to its superior chemical and physical properties as well as wide potential applications.However,the inherent brittleness and unsatisfactory piezoelectric response of piezoelectric semiconductors remain the major obstacles to their diversified applications.Here,flexible multifunctional PVDF/6H-SiC composite fiber films are fabricated and utilized to assemble both piezoelectric nanogenerators(PENGs)and stress/temperature/light sensors.The open cir-cuit voltage(V_(oc))and the density of short circuit current(I_(sc))of the PENG based on the PVDF/5 wt%6H-SiC composite fiber films reach 28.94 V and 0.24μA cm^(-2),showing a significant improvement of 240%and 300%compared with that based on the pure PVDF films.The effect of 6H-SiC nanoparticles(NPs)on inducing interfacial polarization and stress concentration in composite fiber films is proved by first-principles calculation and finite element analysis.The stress/temperature/light sensors based on the composite fiber film also show high sensitivity to the corresponding stimuli.This study shows that the PVDF/6H-SiC composite fiber film is a promising candidate for assembling high-performance energy harvesters and diverse sensors.

关键词： 6H-SiC PVDF Multifunctional composite fiber film Energy harvester Stress/temperature/light sensor

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Structural evolution and high-temperature sensing performance of polymer-derived SiAlBCN ceramics

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Journal of Advanced Ceramics 2024年第4期13卷 478-485页

作者： Chao Ma Kun Liu Pengfei Shao Daoyang Han Kang Wang Mengmeng Yang Rui Zhao hailong Wang Rui Zhang Gang Shao School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Zhongyuan Critical Metal Laboratory Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentZhengzhou UniversityZhengzhou 450002China

In situ temperature monitoring has become extremely imperative in high-temperature harsh environments and polymer-derived ceramics(PDCs)as sensing materials have attracted great attention.However,the stability and oxidation/corrosion resistance of PDCs cannot be simultaneously achieved at the moment,limiting their practical application.Herein,polymer-derived SiAlBCN ceramics were synthesized via polymer conversion method under different pyrolysis temperatures.Their microstructure evolution,high temperature sensing properties,and stability were investigated in detail.The results show that the amorphous SiAlBCN phase grows more orderly and the size of the free carbon phase enlarges with the increasing temperature.The defect concentration displays a decreasing tendency.Concurrently,the SiAlBCN ceramics as sensing materials exhibit a good temperature-resistance property from roo temperature to 1100℃.The fabricated SiAlBCN temperature sensor possesses excellent stability,repeatability,and accuracy.Moreover,SiAlBCN ceramics exhibit distinguished oxidation/corrosion resistance after 100 h treatment at 1200℃in a water/oxygen environment,which is attributed to their low corrosive rate constant(0.57 mg/(cm^(2)·h))and oxidative rate constant(3.43 mg^(2)/(cm^(4)·h)).Therefore,polymer-derived SiAlBCN ceramics as sensing materials,which possess outstanding stability and oxidation/corrosion resistance,have great potential for in-situ monitoring of extreme environmental temperatures in the future.

关键词： polymer-derived SiAlBCN ceramics temperature sensor harsh environments oxidation and corrosion resistance

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Enhanced electromagnetic wave absorption via optical fiber-like PMMA@Ti_(3)C_(2)T_(x)@SiO_(2) composites with improved impedance matching

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Nano Research 2024年第3期17卷 1676-1686页

作者： Huanhuan Niu Xuewen Jiang Wei Li Zhiyu Min Budi Riza Putra Wulan Tri Wahyuni hailong Wang Rui Zhang Bingbing Fan School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China School of Materials Science and Engineering Tongji UniversityShanghai 201804China Department of Materials and Earth Sciences Technical University of DarmstadtDarmstadt 64287Germany School of Material Science and Engineering Luoyang Institute of Science and TechnologyLuoyang 471023China Research Center for Metallurgy National Research and Innovation Agency(BRIN)PUSPIPTEK Gd.470South TangerangBanten 15315Indonesia Analytical Chemistry Division Department of ChemistryFaculty of Mathematics and Natural SciencesIPB UniversityWest Java 16680Indonesia

Ti_(3)C_(2)T_(x) nanosheets have attracted significant attention for their potential in electromagnetic wave absorption(EWA).However,their inherent self-stacking and exorbitant electrical conductivity inevitably lead to serious impedance mismatch,restricting their EWA application.Therefore,the optimization of impedance matching becomes crucial.In this work,we developed polymethyl methacrylate(PMMA)@Ti_(3)C_(2)T_(x)@SiO_(2) composites with a sandwich-like core–shell structure by coating SiO_(2) on PMMA@Ti_(3)C_(2)T_(x).The results demonstrate that the superiority of the SiO_(2) layer in combination with PMMA@Ti_(3)C_(2)T_(x),outperforming other relative graded distribution structures and meeting the requirements of EWA equipment.The resulting PMMA@Ti_(3)C_(2)T_(x)@SiO_(2) composites achieved a minimum reflection loss of-58.08 dB with a thickness of 1.9 mm,and an effective absorption bandwidth of 2.88 GHz.Mechanism analysis revealed that the structural design of SiO_(2) layer not only optimized impedance matching,but also synergistically enhanced multiple loss mechanisms such as interfacial polarization and dipolar polarization.Therefore,this work provides valuable insights for the future preparation of high-performance electromagnetic wave absorbing Ti_(3)C_(2)T_(x)-based composites.

关键词： polymethyl methacrylate(PMMA)@Ti_(3)C_(2)T_(x)@SiO_(2)composites impedance match SiO_(2)layer optical fiber-like structure interfacial polarization and dipolar polarization

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Analysis and Key Parameter Optimization Design of Leningrader Seal Performance

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Wuhan University Journal of Natural Sciences 2024年第2期29卷 177-192页

作者： YANG Dongya WANG Xuelin WANG Feng ZHANG hailong GAO Gui College of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050Gansu China Wenzhou Pump and Valve Engineering Research Institute Lanzhou University of TechnologyWenzhou 325000ZhejiangChina State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000GansuChina

In order to improve the performance and service life of the Leningrader seal of the Stirling engine piston rod,interference,pre-load and friction coefficient were taken as influencing factors,and the curved surface response method was adopted to reduce the contact stress of sealing surface and von Mises stress of the sealing sleeve as the response index,with the optimization goal of reducing wear and extending life.The above three key parameters are analyzed and optimized,the influence of each parameter on the sealing performance and service life is obtained,and the best combination scheme of the three is determined.The results show that the interaction between pre-tightening force and interference fit has the greatest impact on contact stress.The interaction between interference fit and friction coeffi-cient has the most significant effect on von Mises stress.The optimized parameters can reduce the maximum contact stress and maximum von Mises stress of the sealing sleeve by 26.3%and 20.6%,respectively,under a media pressure of 5-9 MPa.Test bench verification shows that the leakage of the optimized sealing device in 12 h is reduced by 0.44 cc·min^(-1)(1 cc=1 cm^(3)).The wear rate of the sealing sleeve is 1.08%before optimization and 0.45%after optimization,indicating that the optimized parameters in this paper are effective.

关键词： Leningrader seal Stirling engine performance analysis optimized design parameter configuration

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Natural attapulgite supported nano-Ni catalysts for the efficient reductive amination of biomass-derived aldehydes and ketones

Green Synthesis and Catalysis

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Green Synthesis and Catalysis 2024年第1期5卷 42-50页

作者： Jia Zhang Jian Yang Xuemei Li Bin Mu hailong Liu Chungu Xia Aiqin Wang Zhiwei Huang State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Key Laboratory of Clay Mineral Applied Research of Gansu Province Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The efficient synthesis of useful primary amines via reductive amination of biomass-based aldehydes and ketones over earth-abundant base metal catalysts is an attractive biomass value-adding technology yet facing lots of challenges.Herein,natural attapulgite(ATP)was applied as support for the fabrication of active Ni catalysts with different Ni loadings(5–30 wt%)by the deposition-precipitation method.The Ni/ATP-550 catalyst with 10–15 wt%Ni loadings was found to present the highest catalytic performance for the synthesis of valuable 5-amino-1-pentanol(5-AP)via reductive amination of biofurfural-derived 2-hydroxytetrahydropyran among a variety of commonly used oxide supports loaded Ni catalysts,as well as ATP supported nickel catalysts with other loadings,achieving 5-AP yield up to 94%.The intrinsic activity of the Ni/ATP catalysts was found to depend strongly on the Ni^(0) crystallite size and Ni^(0) fraction of the catalysts,which generally increased with increasing Ni^(0) crystallite size and fraction,owing probably to the hydrogenation of imine intermediate is a structure-sensitive reaction.The efficient 10Ni/ATP-550 catalyst also exhibited good activity and stability in the reductive amination of several other biomass-derived aldehydes and ketones to their corresponding primary amines with good to excellent yields(81%–99%).This work provided a clean and efficient natural ATP-supported non-noble metal nickel-based catalytic system for the reductive amination of aldehydes and ketones to synthesize high-value-added primary amines,which could be a promising candidate for the industrial production of amines.

关键词： Attapulgite Nano-Ni catalyst Reductive amination 5-Amino-1-pentanol Structure-activity relationship

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Gut microbiota-astrocyte axis: new insights into age-related cognitive decline

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Neural Regeneration Research 2025年第4期20卷 990-1008页

作者： Lan Zhang Jingge Wei Xilei Liu Dai Li Xiaoqi Pang Fanglian Chen hailong Cao Ping Lei Haihe Laboratory of Cell Ecosystem Department of GeriatricsTianjin Medical University General HospitalTianjinChina Tianjin Geriatrics Institute Tianjin Medical University General HospitalTianjinChina Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalNational Key Clinical SpecialtyTianjin Institute of Digestive DiseasesTianjin Key Laboratory of Digestive DiseasesTianjinChina Department of Urology Tianjin Medical University General HospitalTianjinChina Tianjin Neurological Institution Tianjin Medical University General HospitalTianjinChina

With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent worldwide.Aging is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of astrocytes.The microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive function.This article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative diseases.This article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial metabolites.Finally,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s diseases.Our findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition.

关键词： age aging Alzheimer’s disease astrocytes cognitive decline dementia gut microbiota gut–brain axis microbial metabolites neuroinflammation Parkinson’s disease

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Precipitates Generation Mechanism and Surface Quality Improvement for Aluminum Alloy 6061 in Diamond Cutting

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 150-159页

作者：王海龙 DENG Wenping 王素娟 State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006China Guangdong Provincial Key Laboratory of Micro-Nano Manufacturing Technology and Equipment School of Electromechanical EngineeringGuangdong University of TechnologyGuangzhou 510006China

To improve the surface quality for aluminum alloy 6061(Al6061) in ultra-precision machining, we investigated the factors affecting the surface finish in single point diamond turning(SPDT)by studying influence of the precipitates generation of Al6061 on surface integrity and surface roughness.Based on the Johnson-Mehl-Avrami solid phase transformation kinetics equation, theoretical and experimental studies were conducted to build the relationship between the aging condition and the type, size and number of the precipitates for Al6061. Diamond cutting experiments were conducted to machine Al6061 samples under different aging conditions. The experimental results show that, the protruding on the chip surface is mainly Mg_(2)Si and the scratches on the machined surface mostly come from the iron-containing phase(α-, β-AlFeSi).Moreover, the generated Mg_(2)Si and α-, β-AlFeSi affect the surface integrity and the diamond turned surface roughness. Especially, the achieved surface roughness in SPDT is consistent with the variation of the number of AlFeSi and Mg_(2)Si with the medium size(more than 1 μm and less than 2 μm) in Al6061.

关键词： Al6061 precipitates aging treatment diamond cutting surface roughness

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Evaluating CMIP6 models in simulating the North Pacific decadal variability in sea surface salinity

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Science China Earth Sciences 2024年第8期67卷 2661-2680页

作者： Jian CHEN hailong LIU Pengfei LIN Wenrong BAI Chengzu BAI Lu WANG Institute of Atmospheric Physics Chinese Academy of Sciences State Key Laboratory of Geo-Information Engineering Beijing Municipal Climate Center Beijing Meteorological Bureau Space System Department Equipment Department

The North Pacific sea surface salinity(SSS) decadal variability(NPSDV) and its potential forcing were evaluated from 25 coupled models of the Coupled Model Intercomparison Project phase 6(CMIP6) considering the prospects for decadal climate predictions. The results indicated that the CMIP6 models generally reproduced the spatial patterns of NPSDV. The large standard deviation of the SSS anomaly over the strong current regions, such as the Kuroshio-Oyashio Extension(KOE), North Pacific Current(NPC), California Current System(CCS), and Alaskan Coastal Current(ACC), is reflected in the two leading modes of NPSDV: a dipole with out-of-phase loadings in the KOE-NPC versus CCS-ACC and a monopole with positive loading over the KOE-NPC. The order of modes is sensitive to individual models that exhibit discrepancies, especially in temporal phases and power spectra. An autoregressive model of order-1 was used to reconstruct the NPSDV with several forcing terms.The generally weaker influence of forcings in an autoregressive model of order-1 is partly related to the overestimated response time of NPSDV relative to forcings. Most NPSDV variances originate from the persistence of SSS anomalies, but the dominant forcing factors are diverse among models. The model diversity for the NPSDV simulation mainly arises from the influence of the tropical El Ni?o-Southern Oscillation through teleconnection on the North Pacific Oscillation or Aleutian Low with timescale dependence. Conversely, models that can reproduce the NPSDV well are not dependent on those with larger impacts from the North Pacific oceanic processes.

关键词： North Pacific Sea surface salinity Decadal variability CMIP6 Leading mode

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