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Acta Metallurgica sinica(English Letters) 2014年第1期27卷 27-30页

作者： Jiaohong Huang Naikun Sun Cuilan Liu Yumei Ge Tao Zhang Feng Liu pingzhan si Baotou Research Institute of Rare Earths School of Science Shenyang Ligong University College of Materials Science and Engineering China Jiliang University

Bulk ***11.4sil.6 compound exhibits a large magnetic-entropy change ASm of 28.1 J/（kg K） for a magnetic-field change from 0 to 1.5 T at the Curie temperature, Tc of 186 K, accompanied by a large magnetic hysteresis of 56 J/kg and a noticeable thermal hysteresis of about 1 K. If the bulk sample is ground into middle-size particles （30-60 tm）, then the thermal hysteresis is almost eliminated and the magnetic hysteresis loss is decreased by 29%, while the large ASm maintains. Especially, fine powder with an average size of 2 tm shows the same Tc as the bulk and does not lose stability. Meanwhile, a comparatively large ASm of 13.9 J/（kg K） and a hysteresis reduction of 70% are attained. The hysteresis reduction can be ascribed to the decrease of internal strains and to the improvement of heat transfer due to the increase of the ratio of the surface area to the volume.

关键词： Magnetocaloric effect Magnetic hysteresis Particle size

Structure and magnetostriction of Tb_(0.4)Nd_(0.6)(Fe_(0.8)Co_(0.2))_(1.90) alloy prepared by solid-state synthesis

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Rare Metals 2012年第6期31卷 547-551页

作者： Liu Jinjun Wang Rong Yin Hongyun Liu Xincai si pingzhan Du Juan Ningbo Univ State Key Lab Base Novel Funct Mat & Preparat Sci Fac Mat Sci & Chem Engn Ningbo 315211 Zhejiang Peoples R China China Jiliang Univ Coll Mat Sci & Engn Hangzhou 310018 Zhejiang Peoples R China Chinese Acad Sci Ningbo Inst Mat Technol & Engn Ningbo 315201 Zhejiang Peoples R China

Mechanical alloying (MA) and subsequent solid sintering process was used to prepare the Nd-containing magnetostrictive Tb0.4Nd0.6(Fe0.8Co0.2)1.90 alloy. The structure, thermal stability and phase transformation were investigated as functions of composition, milling process and annealing temperature. An amorphous phase was formed by high-energy ball milling for 5 h with the ball-to-powder weight ratio of 20:1, which crystallized into MgCu2-type and PuNi3-type crystalline structure with different annealing temperatures. The magnetoelastic properties were investigated by means of a standard strain technique. The high Nd-content (Tb,Nd)(Fe,Co)2 Laves phase for the composition Tb0.4Nd0.6(Fe0.8Co0.2)1.90 was synthesized by MA process plus annealing at 500 ℃ for 30 min.

关键词： mechanical alloying magnetostriction structure light rare earth

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区域熔炼法制备高 Jc Nd123超导体

低温与超导 2000年第3期28卷 25-27页

作者：司平占樊占国东北大学材料与冶金学院沈阳110006

】Nd1+ x Ba2 - x Cu3Oy超导体以其良好的 Jc- B特性倍受人们注目。文中用区域熔炼技术在空气下制备出取向良好的 Nd1+ x Ba2 - x Cu3Oy 块材 ,采用纯氩下高温退火的办法抑制固溶体的形成 ,得到了零电阻温度 94K、临界电流密度达 540 0 ... 详细信息

】Nd1+ x Ba2 - x Cu3Oy超导体以其良好的 Jc- B特性倍受人们注目。文中用区域熔炼技术在空气下制备出取向良好的 Nd1+ x Ba2 - x Cu3Oy 块材 ,采用纯氩下高温退火的办法抑制固溶体的形成 ,得到了零电阻温度 94K、临界电流密度达 540 0 A/cm2 的超导体。讨论了进一步提高 Jc的可能途径是减少液相的流失并使 Nd4 Ba2 Cu2 O10 相均匀分布。

关键词：区域熔炼高JcNd123超导体制备

水热法制备掺Mn的ZnS纳米线及其磁学性能(英文)

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稀有金属材料与工程 2008年第A2期37卷 261-264页

作者：葛洪良钟敏林华吴琼司平占中国计量学院材料科学与工程学院浙江杭州310018

采用水热法在低温下制备了MnxZn1-xS纳米线。MnxZn1-xS纳米线的形貌和微观结构用透射电子显微镜和X射线衍射仪进行表征。磁性能用振动样品磁强计进行测试。MnxZn1-xS的形貌取决于Mn的含量和在ZnS纳米粒子内外的分布。未掺杂Mn的ZnS纳米... 详细信息

采用水热法在低温下制备了MnxZn1-xS纳米线。MnxZn1-xS纳米线的形貌和微观结构用透射电子显微镜和X射线衍射仪进行表征。磁性能用振动样品磁强计进行测试。MnxZn1-xS的形貌取决于Mn的含量和在ZnS纳米粒子内外的分布。未掺杂Mn的ZnS纳米线的直径和长度分别为80～200nm和10～20μm。随着Mn含量的增加,MnxZn1-xS纳米线的平均直径逐渐增加,长径比不断减小。X射线衍射结果表明MnxZn1-xS纳米结构结晶性好,为六方纤锌矿结构。在Mn的掺杂量为0.25%时,矫顽力达到最大。随着Mn掺杂量的增加,饱和磁化强度也不断非线性增强。

关键词： MnxZn1-xS 纳米线水热磁性能

影响SmCo_5@FeCo软磁相包覆效果的关键因素

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兵器材料科学与工程 2019年第3期42卷 1-5页

作者：姚璐璐王凤青司平占边宝茹郑强杜娟中国计量大学材料科学与工程学院浙江杭州310018 中国科学院宁波材料技术与工程研究所稀土磁性功能材料实验室浙江宁波315201 宁波工程学院材料与化学工程学院浙江宁波315211

为获得良好磁性耦合和高磁能积的纳米复合永磁粉,系统研究了化学法包覆软磁相FeCo的关键影响因素。研究发现,在制备纳米复合磁粉SmCo_5@FeCo过程中表面活性剂的分子量、反应的加热方式、SmCo_5磁粉的预处理时间以及化学包覆反应的时间... 详细信息

为获得良好磁性耦合和高磁能积的纳米复合永磁粉,系统研究了化学法包覆软磁相FeCo的关键影响因素。研究发现,在制备纳米复合磁粉SmCo_5@FeCo过程中表面活性剂的分子量、反应的加热方式、SmCo_5磁粉的预处理时间以及化学包覆反应的时间等对软磁相的形貌、尺寸、分布,以及对复合粉体的磁性能都有重要影响。表面活性剂分子量的调控和加热方式的改善可使相同量软磁相前躯物投入时形成更致密的高含量包覆层。经过酸洗预处理的SmCo_5粉更有利于软磁相包覆,酸洗时间0.5 h为佳。此结果对制备超高性能纳米复合永磁粉体及块体材料具有重要意义。

关键词：双相纳米复合永磁材料化学合成颗粒尺寸磁性能

Unraveling brain aging through the lens of oral microbiota

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Neural Regeneration Research 2025年第7期20卷 1930-1943页

作者： Qinchao Hu si Wang Weiqi Zhang Jing Qu Guang-Hui Liu State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Hospital of Stomatology Guanghua School of StomatologyGuangdong Provincial Key Laboratory of StomatologySun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu HospitalCapital Medical UniversityBeijingChina Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijingChina CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijingChina University of Chinese Academy of Sciences BeijingChina Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijingChina Aging Biomarker Consortium BeijingChina State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Beijing Institute for Stem Cell and Regenerative Medicine BeijingChina

The oral cavity is a complex physiological community encompassing a wide range of *** of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative *** studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention *** this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and *** also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging.

关键词： Alzheimer's disease brain aging multiple sclerosis neurodegeneration neurodegenerative diseases oral microbiota Parkinson's disease periodontitis bacteria Porphyromonas gingivalis

High Fe‑Loading single‑Atom Catalyst Boosts ROS Production by Density Effect for Efficient Antibacterial Therapy

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Nano-Micro Letters 2025年第2期17卷 187-203页

作者： si Chen Fang Huang Lijie Mao Zhimin Zhang Han Lin Qixin Yan Xiangyu Lu Jianlin Shi Department of Cardiology Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai 200092People’s Republic of China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050People’s Republic of China Shanghai Frontiers Science Center of Nanocatalytic Medicine School of MedicineTongji UniversityShanghai 200092People’s Republic of China

The current single-atom catalysts(SACs)for medicine still suffer from the limited active site ***,we develop a synthetic method capable of increasing both the metal loading and mass-specific activity of SACs by exchanging zinc with *** constructed iron SACs(h^(3)-FNC)with a high metal loading of 6.27 wt%and an optimized adjacent Fe distance of~4 A exhibit excellent oxidase-like catalytic performance without significant activity decay after being stored for six months and promising antibacterial ***,a“density effect”has been found at a high-enough metal doping amount,at which individual active sites become close enough to interact with each other and alter the electronic structure,resulting in significantly boosted intrinsic activity of single-atomic iron sites in h^(3)-FNCs by 2.3 times compared to low-and medium-loading ***,the overall catalytic activity of h^(3)-FNC is highly improved,with mass activity and metal mass-specific activity that are,respectively,66 and 315 times higher than those of commercial Pt/*** addition,h^(3)-FNCs demonstrate efficiently enhanced capability in catalyzing oxygen reduction into superoxide anion(O_(2)·^(−))and glutathione(GSH)*** in vitro and in vivo assays demonstrate the superior antibacterial efficacy of h^(3)-FNCs in promoting wound *** work presents an intriguing activity-enhancement effect in catalysts and exhibits impressive therapeutic efficacy in combating bacterial infections.

关键词： Nanocatalytic medicine single-atom catalysts Reactive oxygen species(ROS) High metal loading Oxidase catalysis

Physarum polycephalum-inspired adaptive optimization design of artificial microtubular networks

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Science China Chemistry 2025年

作者： si-Min Zeng Di-Wei Zheng Ting Pan Xing-Lan Ding Yun Zhang Chi-Hui Yang si-Xue Cheng Xian-Zheng Zhang Key Laboratory of Biomedical Polymers of Ministry of Education&Department of Chemistry Wuhan University

Natural biological microtubular networks have undergone adaptive evolutionary selection and may offer viable solutions to design challenges in artificial microtubular networks. The plasmodium of the slime mold Physarum polycephalum(P. polycephalum) extends continuously to form a protoplasmic microtubular network structure, directly connecting food *** simulations revealed that the formation of this adaptive P. polycephalum microtubular network could be captured by a mathematical algorithm. Inspired by the P. polycephalum microtubular networks, we propose an adaptive optimization design method for artificial microtubular networks. Specifically, we utilized hydrogels with biodegradable and tissue-adhesive properties to replicate the P. polycephalum microtubular networks via photomask. In Rhodamine B diffusion and glucosecatalyzed reaction experiments, we found that the P. polycephalum microtubular networks exhibited significantly enhanced efficiency compared to vascular and artificial networks. Furthermore, we demonstrated the potential for uric acid(UA) degradation of the hydrogels with a real P. polycephalum microtubular network loaded with urate oxidase(UOx) in a rodent model of hyperuricemia. And this network achieved more than double the effect of the artificial network. This underscores the potential of natural microtubular networks to replace artificial microtubular networks.

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NOX4 exacerbates Parkinson's disease pathology by promoting neuronal ferroptosis and neuroinflammation

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Neural Regeneration Research 2025年第7期20卷 2038-2052页

作者： Zhihao Lin Changzhou Ying Xiaoli si Naijia Xue Yi Liu Ran Zheng Ying Chen Jiali Pu Baorong Zhang Department of Neurology The Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina

Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra ***,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation,plays a vital role in the death of dopaminergic ***,the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely *** oxidase 4 is related to oxidative stress,however,whether it regulates dopaminergic neuronal ferroptosis remains *** aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis,and if so,by what *** found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease *** oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic ***,NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model ***,we found that NADPH oxidase 4 interacted with activated protein kinase Cαto prevent ferroptosis of dopaminergic ***,by lowering the astrocytic lipocalin-2 expression,NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced *** findings demonstrate that NADPH oxidase 4 promotes ferroptosis of dopaminergic neurons and neuroinflammation,which contribute to dopaminergic neuron death,suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease.

关键词： dopaminergic neuron ferroptosis NADPH oxidase 4(NOX4) neuroinflammation Parkinson's disease

Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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Earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen Tang Sai Zhang FuLiang Xiao HongMing Yang si Liu YiHua He Chang Yang YuYue Jin ZhouKun Deng Ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of Modeling and Monitoring on the Near-Earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation (AKR) is a common radio emission,which can contribute to the magnetosphere-ionosphereatmosphere co u *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500-4500 km and invariant latitude (|ILAT|)=60°-80°has been analyzed.63045 AKR samples have been identified with~48%(52%) samples on the dayside (nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05-08 and 18-22(02-05 and 12-17) in the northern (southern) *** distinct MLT asymmetry is associated with the direction of Bxof the interplaneta ry magnetic *** addition,the occurrence rate on the nightside clearly increases as the AE^(*) index *** study further enriches the information and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field