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Compressive characteristics of closed-cell aluminum foams with different percentages of Er element

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China Foundry 2016年第1期13卷 36-41页

作者： Wei-min Zhao Zan Zhang yong-ning wang Xing-chuan Xia Hui Feng Jing wang School of Materials Science and Engineering Hebei University of Technology Tianjin 300130 China Key Lab for Micro- and Nano-Scale Boron Nitride Materials in Hebei Province China CITIC Dicastal Ltd Qinhuangdao 066011 China

In the present study, closed-cell aluminum foams with different percentages of erbium （Er） element were successfully prepared. The distribution and existence form of erbium （Er） element and its effect on the compressive properties of the foams were investigated. Results show that Er uniformly distributes in the cell walls in the forms of Al3Er intermetallic compound and AI-Er solid solutions. Compared with commercially pure aluminum foam, Er-containing foams possess higher micro-hardness, compressive strength and energy absorption capacity due to solid solution strengthening and second phase strengthening effects. Additionally, the amount of Er element should be controlled in the range of 0.10wt.%-0.50wt.% in order to obtain a good combination of compressive strength and energy absorption properties.

关键词： aluminum foams erbium element compressive property melt foaming method

Structural designs and mechanism insights into electrocatalytic oxidation of 5-hydroxymethylfurfural

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Journal of Energy Chemistry 2025年第1期100卷 792-814页

作者： Jing Lei Huijie Zhang Jian Yang Jia Ran Jiqiang ning Haiyan wang yong Hu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of ChemistryZhejiang Normal UniversityJinhua 321004ZhejiangChina Jinhua Advanced Research Institute Jinhua 321019ZhejiangChina Department of Optical Science and Engineering Fudan UniversityShanghai 200438China College of Chemistry and Materials Engineering Zhejiang A&F UniversityHangzhou 311300ZhejiangChina

Biomass conversion offers an efficient approach to alleviate the energy and environmental *** oxidation of 5-hydroxymethylfurfural(HMF)has attracted tremendous attention in the latest few years for the mild synthesis conditions and high conversion efficiency to obtain 2,5-furan dicarboxylic acid(FDCA),but there still remain problems such as limited yield,short cycle life,and ambiguous reaction *** many reviews highlighting a variety of electrocatalysts for electrochemical oxidation of HMF,a detailed discussion of the structural modulation of catalyst and the underlying catalytic mechanism is still *** herein provide a comprehensive summary of the recent development of electrochemical oxidation of HMF to FDCA,particularly focusing on the mechanism studies as well as the advanced strategies developed to regulate the structure and optimize the performance of the electrocatalysts,including heterointerface construction,defect engineering,single-atom engineering,and in situ *** characterization techniques and theoretical calculation methods for mechanism and active site studies are elaborated,and challenges and future directions of electrochemical oxidation of HMF are also *** review will provide guidance for designing advanced catalysts and deepening the understanding of the reaction mechanism beneath electrochemical oxidation of HMF to FDCA.

关键词： Electrochemical oxidation of 5- hydroxymethylfurfural 2,5-Furan dicarboxylic acid Structural design Mechanism Electrocatalysts

Transsphenoidal approach to pituitary adenoma： surgical technique of the Peking Union Medical College Hospital

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Chinese Medical Journal 2009年第24期122卷 3086-3090页

作者： LI yong-ning wang Ren-zhi LI Gui-lin Department of Neurosurgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China

Although presented over one hundred years ago, the transsphenoidal approach to pituitary adenoma is still the most suitable and safe route to pituitary adenoma, with a series of significant evolutional steps. The transsphenoidal approach to pituitary adenoma is still a non-universal approach used in different centers of different areas in our country. The transsphenoidal approach has a number of variations, including the endonasal rhinoseptoplastic, transnasal displacement,

关键词： transsphenoidal approach surgical technique pituitary adenoma

Enhancing microbial superoxide generation and conversion to hydroxyl radicals for enhanced bioremediation using iron-binding ligands

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Journal of Environmental Sciences 2025年第1期147卷 597-606页

作者： Yuhan wang Xue ning Jinsong Liang Aijie wang Jiuhui Qu School of Civil and Environmental Engineering Harbin Institute of TechnologyShenzhen 518055China SFI MaREI Centre for Energy Climate and MarineEnvironmental Research InstituteUniversity College CorkCorkIreland Center for Water and Ecology Tsinghua UniversityBeijing 100084China

Harnessing bacteria for superoxide production in bioremediation holds immense promise,yet its practical application is hindered by slow production rates and the relatively weak redox potential of *** study delves into a cost-effective approach to amplify superoxide production using an Arthrobacter strain,a prevalent soil bacterial *** research reveals that introducing a carbon source along with specific iron-binding ligands,including deferoxamine(DFO),diethylenetriamine pentaacetate(DTPA),citrate,and oxalate,robustly augments microbial superoxide ***,our findings suggest that these iron-binding ligands play a pivotal role in converting superoxide into hydroxyl radicals by modulating the electron transfer rate between Fe(Ⅲ)/Fe(Ⅱ)and ***,among the tested ligands,only DTPA emerges as a potent promoter of this conversion process when complexed with Fe(Ⅲ).We identify an optimal Fe(Ⅲ)to DTPA ratio of approximately 1:1 for enhancing hydroxyl radical production within the Arthrobacter *** research underscores the efficacy of simultaneously introducing carbon sources and DTPA in facilitating superoxide production and its subsequent conversion to hydroxyl radicals,significantly elevating bioremediation ***,our study reveals that DTPA augments superoxide production in cultures of diverse soils,with various soil microorganisms beyond Arthrobacter identified as contributors to superoxide *** emphasizes the universal applicability of DTPA across multiple bacterial *** conclusion,our study introduces a promising methodology for enhancing microbial superoxide production and its conversion into hydroxyl *** findings hold substantial implications for the deployment of microbial reactive oxygen species in bioremediation,offering innovative solutions for addressing environmental contamination challenges.

关键词： Superoxide Hydroxyl radical Iron-binding ligand Bioremediation DTPA

Profiles,exposure assessment and expanded screening of PAHs and their derivatives in one petroleum refinery facility of China

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Journal of Environmental Sciences 2025年第1期147卷 550-560页

作者： ning wang Fengjiao Jiang Lin Xu Yaqi Cai School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJinan 250101China Resource and Environmental Innovation Institute Shandong Jianzhu UniversityJinan 250101China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 330106China Hubei Key Laboratory of Environmental and Health Effects of Persistence Toxic Substances Institute of Environment and HealthJianghan UniversityWuhan 430056China

This study investigated environmental distribution and human exposure of polycyclic aromatic hydrocarbons(PAHs)and their derivatives in one Chinese petroleum refinery *** was found that,following with high concentrations of 16 EPA PAHs(∑Parent-PAHs)in smelting subarea of studied petroleum refinery facility,total derivatives of PAHs[named as XPAHs,including nitro PAHs(NPAHs),chlorinated PAHs(Cl-PAHs),and brominated PAHs(Br-PAHs)]in gas(mean=1.57×10^(4)ng/m^(3)),total suspended particulate(TSP)(mean=4.33×10^(3) ng/m^(3))and soil(mean=4.37×10^(3) ng/g)in this subarea had 1.76-6.19 times higher levels than those from other subareas of this facility,surrounding residential areas and reference areas,indicating that petroleum refining processes would lead apparent derivation of ***,compared with those in residential and reference areas,gas samples in the petrochemical areas had higher∑NPAH/∑PAHs(mean=2.18),but lower∑Cl-PAH/∑PAHs(mean=1.43×10^(-1))and∑Br-PAH/∑PAHs ratios(mean=7.49×10^(-2)),indicating the richer nitrification of PAHs than chlorination during petrochemical *** occupational exposure to PAHs and XPAHs in this petroleum refinery facility were 24-343 times higher than non-occupational exposure,and the ILCR(1.04×10^(-4))for petrochemical workers was considered to be potential high ***,one expanded high-resolution screening through GC Orbitrap/MS was performed for soils from petrochemical area,and another 35 PAHs were found,including alkyl-PAHs,phenyl-PAHs and other species,indicat-ing that profiles and risks of PAHs analogs in petrochemical areas deserve further expanded investigation.

关键词： Polycyclic aromatic hydrocarbons(PAHs) Derivatives Petroleum refinery Human exposure Non-targeted screening

Advancing gravitational theory through the tetrahedral constellation gravitational wave observatory

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Science China(Physics,Mechanics & Astronomy) 2025年第2期Mechanics & Astronomy) .卷 201-202页

作者： Yun-yong wang Zhou-Jian Cao Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University

The Tetrahedral Constellation Gravitational Wave Observatory(TEGO) [1] represents a significant leap forward in gravitational wave detection, advancing our understanding of gravitational theory. By introducing a fourth spacecraft to form a tetrahedral configuration, TEGO enhances traditional triangular setups, enabling the simultaneous sensitivity to all six gravitational wave polarization modes, including those not predicted by general relativity.

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Experiments and modeling of microstructural and mechanical behaviors of laser-welded Ni-based superalloy at high temperatures

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Chinese Journal of Aeronautics 2025年第1期38卷 99-114页

作者： Ting HOU yong LI Degang wang Yuelin wang Marko VILOTIC School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Department of Structure Shenyang Aircraft Designand Research InstituteShenyang 110000China Engineering Center Shenyang Aircraft CorporationShenyang 110000China Faculty of Technical Science University of Novi SadNovi Sad 21102Serbia

The performance of welded Ni-based superalloys at high temperatures is essential to be evaluated due to their particular service environment for aero-engines and high-speed *** tensile properties and related microstructural evolutions such as the carbide precipitate and grain of a laser-welded Ni-based alloy were experimentally and numerically investigated at different temperatures(20,300,500,800℃).The results show that at room temperature,the strength of the Base Material(BM)was slightly smaller,with a difference of less than 1%,than the Welded Material(WM),which can be attributed to the more uniformly distributed needle-shaped carbide precipitates in the WM than those nonuniformly coarser spherical ones in the *** at 300℃ and 500℃,the strength of WM decreased more obviously compared with that of BM due to the more apparent growth of grain:13.52%loss in yield strength in WM alloys as compared with BM alloys at 300℃,and 16.57% at 500℃.At 800℃,the strength of BM and WM both decreased to a similar level due to Dynamic Recrystallization(DRX).However,a much higher elongation was observed for the BM than WM(less than 50%of BM),which can be attributed to the enhanced dislocation accumulation capability of the large spherical carbides along grain boundaries on the fracture surface in ***,a unified model considering the welding effects on both microstructures(dislocation,carbides,and grain)and mechanical properties evolutions at different temperatures was developed and *** on this model,the key temperature ranges(20–600℃)where apparent weakening of strength and uniform plasticity occurs for welded structures were identified,providing a direct guidance for potential structure and process design.

关键词： Ni-based superalloy Microstructure Mechanical properties Constitutive model High temperature

The Hilbert expansion of the Boltzmann equation in the incompressible Euler level in a channel

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Science China Mathematics 2025年第1期68卷 39-88页

作者： Feimin Huang Weiqiang wang yong wang Feng Xiao Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Computing and Stochastic Mathematics(Ministry of Education) School of Mathematics and StatisticsHunan Normal UniversityChangsha 410081China

The study of the hydrodynamic limit of the Boltzmann equation with physical boundary is a challenging problem due to the appearance of the viscous and Knudsen boundary *** this paper,the hydrodynamic limit from the Boltzmann equation with the specular reflection boundary condition to the incompressible Euler equations in a channel is *** on the multi-scaled Hilbert expansion,the equations with boundary conditions and compatibility conditions for interior solutions,and viscous and Knudsen boundary layers are derived under different scaling,***,some uniform estimates for the interior solutions,and viscous and Knudsen boundary layers are *** the help of the L^(2)-L^(∞) framework and the uniform estimates obtained above,the solutions to the Boltzmann equation are constructed by the truncated Hilbert expansion with multiscales,and hence the hydrodynamic limit in the incompressible Euler level is justified.

关键词： Boltzmann equation incompressible Euler equations hydrodynamic limit Hilbert expansion specular reflection boundary condition viscous boundary layer Knudsen boundary layer

The pivotal role of microglia in injury and the prognosis of subarachnoid hemorrhage

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Neural Regeneration Research 2025年第7期20卷 1829-1848页

作者： Wenjing ning Shi Lv Qian wang Yuzhen Xu Department of Rehabilitation The Second Affiliated Hospital of Shandong First Medical UniversityTaianShandong ProvinceChina Department of Central Laboratory The Affiliated Taian City Central Hospital of Qingdao UniversityTaianShandong ProvinceChina

Subarachnoid hemorrhage leads to a series of pathological changes,including vascular spasm,cellular apoptosis,blood–brain barrier damage,cerebral edema,and white matter ***,which are the key immune cells in the central nervous system,maintain homeostasis in the neural environment,support neurons,mediate apoptosis,participate in immune regulation,and have neuroprotective *** evidence has shown that microglia play a pivotal role in the pathogenesis of subarachnoid hemorrhage and affect the process of injury and the prognosis of subarachnoid ***,microglia play certain neuroprotective roles in the recovery phase of subarachnoid *** approaches aimed at modulating microglia function are believed to attenuate subarachnoid hemorrhage *** provides new targets and ideas for the treatment of subarachnoid ***,an in-depth and comprehensive summary of the role of microglia after subarachnoid hemorrhage is still *** review describes the activation of microglia after subarachnoid hemorrhage and their roles in the pathological processes of vasospasm,neuroinflammation,neuronal apoptosis,blood–brain barrier disruption,cerebral edema,and cerebral white matter *** also discusses the neuroprotective roles of microglia during recovery from subarachnoid hemorrhage and therapeutic advances aimed at modulating microglial function after subarachnoid ***,microglia in subarachnoid hemorrhage are targeted with TLR inhibitors,nuclear factor-κB and STAT3 pathway inhibitors,glycine/tyrosine kinases,NLRP3 signaling pathway inhibitors,Gasdermin D inhibitors,vincristine receptorαreceptor agonists,ferroptosis inhibitors,genetic modification techniques,stem cell therapies,and traditional Chinese ***,most of these are still being evaluated at the laboratory *** clinical studies and data on subarachnoid hemorrhage are required to improve the treatment of subarachnoid hemor

关键词： apoptosis blood–brain barrier brain edema microglia neuroinflammation neuron neuroprotection subarachnoid hemorrhage vasoconstriction white matter injury