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Oxygen deficiency mechanism of La3Ni2O7–δunder pressure

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Science China(Physics,Mechanics & Astronomy) 2025年第04期Mechanics & Astronomy) .卷 175-183页

作者： Yu Chen Ke Zhang Minghui xu yan Zhao Haiyan Xiao Liang qiao School of Physics University of Electronic Science and Technology of China

The recent discovery of superconductivity in pressurized bilayer nickelate La3Ni2O7has triggered tremendous research ***,the experimentally observed oxygen deficiency implies that obtaining perfect stoichiometric single crystals is still *** influence of oxygen deficiency on physical properties remains ***,we construct a chemical potential phase diagram to characterize the stability of *** narrow stable region explains the difficulty of synthesizing pure ***,oxygen defect studies reveal that the interlayer apical oxygen vacancy has the highest defect concentrations and is responsible for oxygen ***,unfolding band structures show as the oxygen-deficient variant increases,Ni 3dz2 bands shift toward a lower energy position under the Fermi level atΓpoint,which is adverse to the metallization of Ni 3dz2 ***,high-pressure calculations indicate that oxygen vacancy would destroy the hybridization of interlayer Ni 3dz2 orbitals,and the larger the oxygen deficiency,the higher the pressure needed to metalize the Ni ***,the oxygen deficiency would suppress the emergence of superconductivity in La3Ni2O7–δ.Our results elucidate the mechanism of oxygen deficiency for superconductivity in La3Ni2O7–δand provide instructive guidance to the experimental research.

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Electronic modulation induced by coupling RuO2 with electron-donating Co3O4 for high-active and long-life rechargeable Zn-air batteries

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Journal of Energy Chemistry 2025年第2期101卷 99-109页

作者： xuena Ma Zhangxin xu Mingyang Liu Panzhe qiao Qi Li Ruihong Wang Baojiang Jiang Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People's Republic of China School of Chemistry and Materials ScienceHeilongjiang University Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences

Electronic-state modulation strategy offers great potential in designing RuO2-based bifunctionalelectrocatalysts for rechargeable Zn-air batteries（ZABs）.Various three-dimensional（3D） transition metal oxides are attempted to couple with RuO2for constructing an appropriate Ru—O—M *** work aims to construct Co3O4-RuO2heterostructures on carbon sheets（Co3O4/RuO2/NCNS） for boosting electronic transfer and *** and theoretical calculations identify the electronic transfer from Co3O4to RuO2that modulates the electronic structure of metal surfaces/***,it leads to the increase in Co3+content,electron-rich state at RuO2surface and electronic accumulation at ***,this electronic-state modulation optimizes the d-band center in Co3O4/RuO2that lowers the reaction barriers and endows interfaces as the biggest contributor to oxygen reduction reaction（ORR） and oxygen evolution reaction（OER） performance,The Co3O4/RuO2/NCNS shows a quite low potential difference of 0.62 V and remarkable durability for ORR/***3O4/RuO2/NCNS-assembled ZABs exhibit an excellent specific capacity of 818.3 mA h g-1and a superior lifespan over 750 h.

关键词： Charge-discharge stability Co3O4-RuO2 heterostructure Electronic modulation Reaction energy barrier Zn-air battery

“Superimposed”spectral characteristics of fluorophores arising from cross-conjugation hybridization

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Chinese Chemical Letters 2025年第1期36卷 442-446页

作者： Kai An Qinglong qiao Lovelesh Syed Ali Abbas Abedi Xiaogang Liu Zhaochao xu CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China Fluorescence Research Group Singapore University of Technology and DesignSingapore 487372Singapore

The demand for enhanced optical properties in advanced fluorescence technologies has driven research into the structure-property relationship of *** this paper,we use naphthalene fluorophores Na DC-Aze and PhDO-Aze as a case study to emphasize the pivotal role of cross conjugation in tuning the optical structure-property *** DC-Aze and PhDO-Aze,formed by hybridizing two distinct conjugated systems in a single naphthalene molecule,exhibit spectral characteristics from both conjugated *** data and theoretical calculations demonstrate the coexistence of two electron-delocalization systems in a cross-conjugation manner in both Na DC-Aze and *** cross-conjugation fluorophores exhibit high brightness,large Stokes shift,and a broad absorption wavelength range by combining distinct spectral properties from its parent *** spectral properties will be advantageous for certain applications(i.e.,panchromatic absorption in organic solar cells,and fluorophores compatible with a wide range of excitation wavelengths).

关键词： Fluorophore Cross conjugation Absorption Emission Naphthalene

Numerical simulation of microstructure and microporosity morphology in directional solidification of aluminum-copper alloys:Effect of copper content and withdrawal rate

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China Foundry 2025年第1期22卷 33-44页

作者： Wei Yuan Hai-dong Zhao xu Shen Chun Zou Yuan Liu Qing-yan xu National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Tsinghua UniversityBeijing 100084China

Microporosity formed in the solidification process of Al alloys is detrimental to the alloy properties.A two-dimensional cellular automaton(CA)model was developed to simulate the microstructure and microporosity formation in Al-Cu alloys,considering variations in Cu content and solidification *** results indicate that the Cu content primarily influences the growth of *** validate the model,directional solidification experiments were conducted on Al-Cu alloys with varing Cu contents and withdrawal *** experimental results of dendrites and microporosity characteristics agree well with the predictions from the developed model,thus confirming the validity of the *** alloy’s liquidus temperature,dendrite morphology,and hydrogen saturation solubility arising from different Cu contents have significant effects on microporosity *** withdrawal rate primarily affects the nucleation of hydrogen microporosity by altering cooling rates and dendritic growth rates,resulting in different microporosity characteristics.

关键词： microporosity dendrites cellular automaton Al-Cu alloys directional solidification

Functional abnormalities of the glymphatic system in cognitive disorders

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Neural Regeneration Research 2025年第12期20卷 3430-3447页

作者： Wuyue Shentu Qi Kong Yier Zhang Wenyao Li Qiulu Chen Sicheng yan Junjun Wang Qilun Lai Qi xu Song qiao The Second Clinical Medical College Zhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Department of Neurology Zhejiang HospitalHangzhouZhejiang ProvinceChina Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University HangzhouZhejiang ProvinceChina Department of Neurology Zhejiang Medical&Health Group Hangzhou HospitalHangzhouZhejiang ProvinceChina Department of Neurology Liuzhou People’s HospitalLiuzhouGuangxi Zhuang Autonomous RegionChina Department of Radiology Zhejiang HospitalHangzhouZhejiang ProvinceChina

Various pathological mechanisms represent distinct therapeutic targets for cognitive disorders,but a balance between clearance and production is essential for maintaining the stability of the brain's internal ***,the glymphatic system may represent a common pathway by which to address cognitive *** the established model of the glymphatic system as our foundation,this review disentangles and analyzes the components of its clearance mechanism,including the initial inflow of cerebrospinal fluid,the mixing of cerebrospinal fluid with interstitial fluid,and the outflow of the mixed fluid and the *** section summarizes evidence from experimental animal models and human studies,highlighting the normal physiological properties of key structures alongside their pathological manifestations in cognitive *** same pathologic manifestations of different cognitive disorders appearing in the glymphatic system and the same upstream influences are main points of interest of this *** conclude this article by discussing new findings and outlining the limitations identified in current research progress.

关键词： aquaporin-4 astrocyte cerebrospinal fluid dynamics cognitive disorders glymphatic system

Sex differences in human pre-gastrulation embryos

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Science China(Life Sciences) 2025年第2期68卷 397-415页

作者： Yongjie Lu Meng Qin Xintong Qi Ming yang Fan Zhai Jiaqi Zhang Zhiqiang yan Liying yan Jie qiao Peng Yuan State Key Laboratory of Female Fertility Promotion Center for Reproductive MedicineDepartment of Obstetrics and GynecologyPeking University Third HospitalBeijing 100191China National Clinical Research Center for Obstetrics and Gynecology(Peking University Third Hospital) Beijing 100191China Key Laboratory of Assisted Reproduction(Peking University) Ministry of EducationBeijing 100191China Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology Beijing 100191China Academy for Advanced Interdisciplinary Studies Peking UniversityBeijing 100871China

Human fetuses exhibit notable sex differences in growth rate and response to the intrauterine environment,yet their origins and underlying mechanisms remain ***,we conduct a detailed investigation of sex differences in human pre-gastrulation *** lower methylation and incomplete inactivation of the X chromosome in females,as well as the sex-specific cell-cell communication patterns,contribute to sex-differential *** trophectoderm is more inclined toward syncytiotrophoblast differentiation and exhibits a stronger hormone secretion capacity,while female trophectoderm tends to retain cytotrophoblast program with stronger mitochondrial function as well as higher vasculogenesis and immunotolerance *** primitive endoderm initiates the anterior visceral endoderm transcriptional program earlier than *** cell cycle activities of the epiblast and primitive endoderm are higher in males compared to females,while the situation is opposite in the *** conclusion,our study provides in-depth insights into the sex differences in human pre-gastrulation embryos and contributes to unraveling the origins of the sex differences in human fetal development.

关键词： human embryo sex difference trophectoderm primitive endoderm epiblast

Construction of attapulgite-based one-dimensional nanonetwork composites with corrosion resistance for high-efficiency microwave absorption

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 689-698页

作者： Kai xu Qingqing Gao Shaoqi Shi Pei Liu Yinxu Ni Zhilei Hao Gaojie xu yan Fu Fenghua Liu School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Zhejiang Key Laboratory of Additive Manufacturing Materials Ningbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo 315201China Northwest Yongxin Coatings Limited Company Lanzhou 730046China

Exploring high-efficiency and broadband microwave absorption(MA)materials with corrosion resistance and low cost is ur-gently needed for wide practical ***,the natural porous attapulgite(ATP)nanorods embedded with TiO_(2)and polyaniline(PANI)nanoparticles are synthesized via heterogeneous precipitation and in-situ *** obtained PANI-TiO_(2)-ATP one-di-mensional(1D)nanostructures can intertwine into three-dimensional(3D)conductive network,which favors energy *** min-imum reflection loss(RL_(min))of the PANI-TiO_(2)-ATP coating(20wt%)reaches-49.36 dB at 9.53 GHz,and the effective absorption band-width(EAB)can reach 6.53 GHz with a thickness of 2.1 *** excellent MA properties are attributed to interfacial polarization,mul-tiple loss mechanisms,and good impedance matching induced by the synergistic effect of PANI-TiO_(2)nanoparticle shells and ATP *** addition,salt spray and Tafel polarization curve tests reveal that the PANI-TiO_(2)-ATP coating shows outstanding corrosion resist-ance *** study provides a low-cost and high-efficiency strategy for constructing 1D nanonetwork composites for MA and corrosion resistance applications using natural porous ATP nanorods as carriers.

关键词： microwave absorption corrosion resistance attapulgite TiO_(2) polyaniline

Establishing a new testing protocol of the electrochemical stability window for electric double-layer capacitors

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Science China Chemistry 2025年第1期68卷 217-225页

作者： Ruilin Hou Xiaoxi Zhao Tingting Liang Qingyun Dou Shan xu Xingbin yan School of Materials Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China Laboratory of Clean Energy Chemistry and Materials Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Industrial Analysis and Testing Guangdong Academy of ScienceGuangzhou 510651China College of Engineering and Applied Sciences Nanjing UniversityNanjing 210093China

The electrochemical stability window(ESW)is crucial for determining the energy density of electric double-layer capacitors(EDLCs).However,current ESW testing protocols of EDLCs are strongly affected by artificial factors,thereby leading to unreliable *** solve this problem,we first identify the key shortcomings of the traditional protocols by analyzing their test ***,taking an aqueous carbon-based EDLC as an example,we design a side reaction descriptor to represent the response difference in the charging capacitance to side reactions between the cyclic voltammetry and galvanostatic chargedischarge *** the aid of this descriptor,we propose a new ESW testing protocol,which is not only able to completely avoid the adverse influence of subjective factors but also fully consider the operating condition *** protocol can be extended from the single electrode to the full *** work proposes a more rigorous definition of ESW and provides a reliable protocol for evaluating the ESW of EDLCs.

关键词： electric double-layer capacitors electrochemical stability window testing protocol side reaction descriptor operating limitation

B2-CuZr reinforced amorphous alloy matrix composites:A review

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China Foundry 2025年第1期22卷 1-11页

作者： Wei Guo Run-hua Huang Zhen Zhang Mi Zhao Jin-cheng Wang yan-qiang qiao Shu-lin Lü Shu-sen Wu State Key Lab of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan 430074China Research Institute of Huazhong University of Science and Technology in Shenzhen Shenzhen 518057GuangdongChina

B2-CuZr phase reinforced amorphous alloy matrix composites has become one of the research hotspots in the field of materials science due to the“transformation-induced plasticity”phenomenon,which makes the composites show better macroscopic plastic deformability and obvious work-hardening behavior compared to the conventional amorphous alloy matrix composites reinforced with ductile ***,the in-situ metastable B2-CuZr phase tends to undergo eutectoid decomposition during solidification,and the volume fraction,size,and distribution of B2-CuZr phase are difficult to control,which limits the development and application of these *** date,much efforts have been made to solve the above problems through composition optimization,casting parameter tailoring,and post-processing *** this study,a review was given based on relevant studies,focusing on the predictive approach,reinforcing mechanism,and microstructure tailoring methods of B2-CuZr phase reinforced amorphous alloy matrix *** research focus and future prospects were also given for the future development of the present composite system.

关键词： amorphous alloy matrix composite B2-CuZr phase plasticity microstructure tailoring