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Graphene Aerogel Composites with Self‑Organized Nanowires‑Packed Honeycomb Structure for Highly Efficient Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第2期17卷 533-547页

作者： Xiao You Huiying ouyang Ruixiang Deng Qiuqi Zhang Zhenzhong xing Xiaowu Chen Qingliang Shan Jinshan Yang Shaoming Dong State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Key Laboratory of Inorganic Coating Materials CAS Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210People’s Republic of China School of Materials Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China University of Chinese Academy of Sciences Beijing 100039People’s Republic of China

With vigorous developments in nanotechnology,the elaborate regulation of microstructure shows attractive potential in the design of electromagnetic wave ***,a hierarchical porous structure and composite heterogeneous interface are constructed successfully to optimize the electromagnetic loss *** macro–micro-synergistic graphene aerogel formed by the ice template‑assisted 3D printing strategy is cut by silicon carbide nanowires(SiC_(nws))grown in situ,while boron nitride(BN)interfacial structure is introduced on graphene *** unique composite structure forces multiple scattering of incident EMWs,ensuring the combined effects of interfacial polarization,conduction networks,and magnetic-dielectric ***,the as-prepared composites present a minimum reflection loss value of−37.8 dB and a wide effective absorption bandwidth(EAB)of 9.2 GHz(from 8.8 to 18.0 GHz)at 2.5 ***,relying on the intrinsic high-temperature resistance of SiC_(nws) and BN,the EAB also remains above 5.0 GHz after annealing in air environment at 600℃ for 10 h.

关键词： Hierarchical porous structure Interface High-temperature resistance Graphene aerogel composites Electromagnetic wave absorption

Effect of energy density on defect evolution in 3D printed Zr-based metallic glasses by selective laser melting

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Science China(Physics,Mechanics & Astronomy) 2020年第2期63卷 104-110页

作者： Wei xing Di ouyang Zhen Chen Lin Liu School of Materials Science and Engineering and State Key Lab for Materials Processing and Die&Mould TechnologyHuazhong University of Science and TechnologyWuhan 430074China State Key Lab for Manufacturing Systems Engineering Xi’an Jiaotong UniversityXi’an 710049China

In this study, the defects in 3D printed Zr-based bulk metallic glasses(BMGs) fabricated by selective laser melting(SLM) under different energy densities have been investigated via both experimental and simulation approaches. Different defects, including balling, interlayer pores, open pores and metallurgical pores, are detected in the 3D-printed Zr-based MGs depending on the energy inputs. Balling mainly occurs at a relatively low energy density(E<8.33 J/mm^3) due to the incomplete melting of particles, while interlayer pores and open pores are formed at modest energy densities(E=13.89-16.67 J/mm^3) because of incomplete welding and insufficient filling of molten liquid between layers. Fine metallurgical pores appear on the upper surface at relatively high energy densities(E=20.83-27.78 J/mm^3), which originate from gas escaping from molten pools during rapid solidification of the melt. Computational fluid dynamics(CFD) simulations are carried out to verify the experimental observations. The CFD simulations reveal that the various defects formed in the 3D-printed Zr-based BMG are related to the melt flow behaviours in the molten pools under different energy densities. The present work provides in-depth understandings of defect formation in the SLM process and provides methods for eliminating these defects in order to enhance the mechanical performance of 3D printed BMGs.

关键词： metallic glass selective laser melting defect formation mesoscopic simulation

Existence of Semilinear Differential Equations with Nonlocal Initial Conditions

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Acta Mathematica Sinica,English Series 2007年第6期23卷 983-988页

作者： xing mei XUE Department of Mathematics Southeast University Nanjing 210096 P. R. China

In this paper we give the existence of mild solutions for semilinear Cauchy problems u′（t） = Au（t）＋f（t, u（t））, t ∈ I, a.e. with nonlocal initial condition u（O） = g（u）＋uo when the map g loses compactn... 详细信息

关键词： nonlocal condition compact semigroup mild solution

中国老年人午睡时长和夜间睡眠与抑郁症状的关联:基于2020年CHARLS数据的实证分析

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中国全科医学 2025年第5期28卷 560-567页

作者：周梅杨爱琼邢英王玉玲新疆医科大学第一附属医院干部保健中心新疆维吾尔自治区乌鲁木齐市830054

背景随着我国进入中度老龄化社会,老年人心理健康问题逐年增加,而生活习惯与老年人的心理健康密切相关。目的探讨我国老年人午睡时长、夜间睡眠与抑郁症状的关系,基于生活习惯角度推荐睡眠时间,为老年人抑郁早期防控提供科学依据。方法... 详细信息

背景随着我国进入中度老龄化社会,老年人心理健康问题逐年增加,而生活习惯与老年人的心理健康密切相关。目的探讨我国老年人午睡时长、夜间睡眠与抑郁症状的关系,基于生活习惯角度推荐睡眠时间,为老年人抑郁早期防控提供科学依据。方法基于2023-11-16公开发布第五轮(2020年)中国健康与养老追踪调查项目(CHARLS),纳入符合研究标准的8233名为研究对象。采用抑郁评定量表(CSE-D10)评估老年人抑郁症状,午睡时长划分5级:不午睡、<30 min、30~59 min、60~89 min、≥90 min,夜间睡眠分为5级:≥8 h、7~<8 h、6~<7 h、5~<6 h、<5 h。采用多因素Logistic回归分析探究影响老年人发生抑郁症状的因素,随机森林模型分析午睡时长、夜间睡眠在老年人发生抑郁症状中的重要程度,限制性立方样条曲线进一步探索午睡时长、夜间睡眠时长与抑郁症状发生风险之间的剂量-反应关系。结果2020年调查期间,中国老年人抑郁症状的发生率为24.84%(2045/8233)。多因素Logistic回归分析结果显示,午睡时长30~59 min是老年人发生抑郁症状的保护因素(OR=0.814,95%CI=0.673~0.985,P=0.034),夜间睡眠时间<5 h是老年人发生抑郁症状的危险因素(OR=1.705,95%CI=1.435~2.027,P<0.001)。女性、未婚/分居/离异/丧偶、失能、身体疼痛、强度体力活动、自评健康状况下降、生活满意度下降、卒中、帕金森病会增加老年人发生抑郁症状的风险(P<0.05)。随机森林模型显示,午睡时长、夜间睡眠时间对抑郁症状影响的重要性较高。午睡时长与发生抑郁症状之间存在非线性关系(P_(nonlinear)<0.05),老年人发生抑郁症的风险在午睡时长30 min后随着时间的增加而持续降低,最低水平约为50 min,午睡时长超过75 min后抑郁症状的发生风险会增加。老年人患抑郁症状的发生风险在夜间睡眠6 h后随着时间的增加而持续降低,最低水平约为7 h,睡眠时间超过9 h后抑郁的风险会增加(Poverall<0.05)。结论中国老年人群抑郁症的患病率较高(24.84%),午睡时长、夜间睡眠的持续时间与抑郁症之间呈J型关系,建议老年人每天午睡30~75 min,适度的午睡时长有效降低老年人发生抑郁症状的风险,同时夜间睡眠6~9 h降低抑郁症状的发生风险,对老年人群抑郁症的早期防控具有一定的意义。

关键词：抑郁老年人午睡时长夜间睡眠中国健康与养老追踪调查项目

Enhancing hydrothermal stability of framework Al in ZSM-5:From the view on the transformation between P and Al species by solid-state NMR spectroscopy

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Chinese Journal of Chemical Engineering 2020年第12期28卷 3052-3060页

作者： Lei Han Ying ouyang Enhui xing Yibin Luo Zhijian Da State Key Laboratory of Catalytic Materials and Reaction Engineering Research Institute of Petroleum ProcessingSinopecBeijing 100083China

HZSM-5,with good surface acidity and shape selectivity,was reported as hydrocarbon cracking catalyst for multiple decades,however the hydrothermal stability,especially dealumination of tetrahedrally coordinated framework aluminum(TFAl),has been proved extensively as one of the major challenges during reactionregeneration *** was proposed to stabilize TFAl and indeed it enhanced the hydrothermal ***,most of the phosphorus species would remain outside of the zeolite pore,mainly as polyphosphate species,and block the micropore severely,with only a limited portion introduced into the channel being able to interact with *** the pore size by alkali treatment(desilication)is one of the most convinced methods,but the details about specific P species during alkali treatment and its transformation upon hydrothermal activation is not acquired,thus the mechanism has not been fully ***,the P-containing species and its transformation during direct P modification and acid/alkali treatment followed by Pmodification have been studied,and the mechanism on the interaction between P and Al species has been investigated,using several analytical methods,especially Solid-state nuclear magnetic resonance(SSNMR)*** was found that the combination of desilication and subsequent phosphorus modification can enhance the activity of the ZSM-5 for the cracking of ethylcyclohexane,due to the better hydrothermal stabilization of acid sites by the enhanced interaction between phosphorus and TFAl,resulting from the improved accessibility of TFAl because of the successful generation of *** the acid treatment followed by phosphorus modification,with declined retention of crystallinity and P/Al ratio,monoclinic/orthorhombic transition during steam activation,and the failed generation of mesopores,would cause obvious aggregation of the phosphorus species and could not improve the hydrothermal stability of the ZSM-5 ef

关键词： Phosphorus modification TFAl NaOH/alkali treatment Interaction ZSM-5

Palladium-catalysed diastereodivergent inverse- electron-demand oxa-Diels–Alder reactions of in situ formed cyclopentadienones via ligand- control

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Organic Chemistry Frontiers 2022年第5期9卷 1364-1369页

作者： xing-xing Yang xing-Liang Zhao Qin ouyang Wei Du Ying-Chun Chen Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China College of Pharmacy Third Military Medical UniversityShapingbaChongqing 400038China

Here we report Pd(0)-catalysed asymmetric inverse-electron-demand oxa-Diels–Alder reactions between the carbonates of 4-hydroxy-2-cyclopentenones andα-cyano chalcones by in situ generating η^(2)-Pd(0)-cyclopentadienone complexes as HOMO-raised dienophiles,and diastereodivergent synthesis could be realised by employing a bifunctional monophosphine ligand from a chiral aminoalcohol or a proline-derived bisphosphine ligand.

关键词： inverse Palladium stereo

Extrinsic and intrinsic factors controlling spermatogonial stem cell self-renewal and differentiation

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Asian Journal of Andrology 2015年第3期17卷 347-354页

作者： xing-xing mei Jian Wang Ji Wu Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education) Bio-X Institutes Shanghai Jiao Tong University Shanghai 200240 China Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education Ningxia Medical University Yinchuan 750004 China Shanghai Key Laboratory of Reproductive Medicine Shanghai 200025 China

Spermatogonial stem cells （SSCs）, the stem cells responsible for male fertility, are one of a small number of cells with the abilities of both self-renewal and generation of large numbers of haploid cells. Technology improvements, most importantly, transplantation assays and in vitro culture systems have greatly expanded our understanding of SSC self-renewal and differentiation. Many important molecules crucial for the balance between self-renewal and differentiation have been recently identified although the exact mechanism（s） remain largely undefined. In this review, we give a brief introduction to SSCs, and then focus on extrinsic and intrinsic factors controlling SSCs self-renewal and differentiation.

关键词： differentiation self-renewal signal spermatogonial stem cells

Comparative adsorption of heavy metal ions in wastewater on monolayer molybdenum disulfide

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Green Energy & Environment 2021年第5期6卷 751-758页

作者： Zheng Zhang Kai Chen Qiang Zhao mei Huang Xiaoping ouyang Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy North China Electric Power UniversityBeijing102206China School of Nuclear Science and Engineering North China Electric Power UniversityBeijing102206China Northwest Institute of Nuclear Technology Xi'an710024China School of Materials Science and Engineering Xiangtan UniversityXiangtan411105China

To maximize the potential of monolayer molybdenum disulfide(MoS2)sheet in the disposal of heavy metal ions in wastewater,we compared the adsorption of several common heavy metal ions(including Cr^(3+),Ni^(2+),Cu^(2+),Zn^(2+),Cd^(2+),Hg^(2+),and Pb^(2+))in wastewater on the monolayer MoS2 sheet through first-principles *** simulation results show that the monolayer MoS2 sheet is a potential heavy metal adsorption material because of the attractive interaction between *** most negative adsorption energy determines that the TMo site is the most stable adsorption site for the heavy metal *** attractive interaction is considered as chemical adsorption,and it is closely related to charge *** orbital hybridization between S p and heavy metal ions p and d states electrons contributes to the adsorption,except the orbital hybridization between S p and Pb p states electrons contributes to the Pb^(2+) *** the results show that the monolayer MoS2 sheet is most suitable for removing Ni^(2+) and Cr^(3+) ions from wastewater,followed by Cu^(2+) and Pb^(2+).For the ions Cd^(2+),Zn^(2+),and Hg^(2+),its adsorption strength remains to be improved.

关键词： Monolayer MoS2 Heavy metal ions Adsorption Wastewater First-principles calculation

Circular patterns of calcium oxalate crystals induced by defective Langmuir-Blodgett film

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Science China Chemistry 2008年第1期51卷 25-30页

作者： DENG SuiPing ouyang JianMing XIE YuShan xing FeiYue Institute of Biomineralization and Lithiasis Research Jinan UniversityGuangzhou 510632China

The injury of the renal epithelial cell membrane can promote the nucleation of nascent crystals, as well as adhesion of crystals on it. It thus accelerates the formation of renal calculi. In this paper, the defective Langmuir-Blodgett (LB) films were used as a model system to simulate the injured renal epithelial cell membrane. The microcosmic structure of the defective LB film and the molecular mechanism of the effect of this film on nucleation, growth, deposited patterns and adhesion of calcium oxalate monohydrate (COM) were investigated. The circular defective domains were formed in dipalmitoylphosphatidylcholine (DPPC) LB film after the film was treated by potassium oxalate. These domains could induce ring-shaped patterns of COM crystals. In comparison, the LB film without pretreatment by potassium oxalate only induced random growth of hexagonal COM crystals. As the crystallization time increased, the size of COM crystals in the patterns increased, the crystal patterns changed from empty circles to solid circles, and the number of the circular patterns with small size (5-20 μm) increased. The results would shed light on the molecular mechanism of urolithiasis induced by injury of the renal epithelial membrane at the molecular and supramolecular level.

关键词： defective LB Film calcium oxalate SEM biomineralization