检索结果-南通市图书馆

Origin of the near-room temperature resistance transition in lutetium with H2/N2 gas mixture under high pressure

national Science Review 2024年第7期11卷 26-32页

作者： Di Peng Qiaoshi Zeng Fujun Lan Zhenfang Xing Zhidan Zeng Xiaoxing Ke Yang Ding Ho-kwang Mao key laboratory of materials Physics Institute of Solid State Physics Hefei Institutes of Physical Science(HFIPS)Chinese Academy of Sciences Science Island Branch Graduate School of University of Science and Technology of China Center for High Pressure Science and Technology Advanced Research Shanghai key laboratory of Material Frontiers Research in Extreme Environments(MFree) Shanghai Advanced Research in Physical Sciences(SHARPS) State key laboratory of superhard materials Institute of PhysicsJilin University College of materials Science&Engineering Beijing University of Technology

The recent report of room-temperature superconductivity at near-ambient pressure in nitrogen-doped lutetium hydride（Lu-H-N） by Dasenbrock-Gammon et al. [Nature 615, 244–250（2023）] has attracted tremendous attention due to its anticipated great impact on technology. However, the results could not be independently reproduced by other groups worldwide in follow-up studies, which elicited intense controversy. Here, we develop a reliable experimental protocol to minimize the extensively concerned extrinsic influences on the sample by starting the reaction from pure lutetium loaded with an H2/N2gas mixture in a diamond anvil cell under different pressures and temperatures and simultaneously monitoring the entire chemical reaction process using in situ four-probe resistance measurements. Therefore, we could repeatedly reproduce the near-room temperature upsurge of electrical resistance at a relatively early stage of the chemical reaction. However, the mechanism is suggested to be a metal-to-semiconductor/insulator transition associated with the structural modulation in the non-stoichiometric Lu-H-N, rather than superconductivity.

关键词： superconductivity high pressure lutetium hydride resistance transition metal-to-semiconductor/insulator transition

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Unveiling a Novel Insulator-to-Metal Transition in La_(N)iO_(4+δ):Challenging High-Temperature Superconductivity Claimed for Single-Layer Lanthanum Nickelates

引用

Chinese Physics Letters 2024年第9期41卷 93-106页

作者： Yunqi Ji Xiaohan Wang Xiaohe Li Wenting Tang Xinyang Li Xin Wang Fangfei Li Liang Li Qiang Zhou Synergetic Extreme Condition User Facility State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China

La_(2)NiO_(4)has a similar structure to La_(2)CuO_(4)and was proposed as a high-temperature superconductor based on magnetic-moment measurements decades ***,with the exception for electrical resistance drop behavior of about 4 orders of magnitude that is claimed to originate from the superconductivity ever observed in Sr-doped La_(N)iO_(4),most electrical data reported to date in La_(N)iO_(4)system exhibit a trivial insulating ground ***,we definitively identify the similar electrical resistance drop behavior of more than 3 orders of magnitude in La_(2)NiO_(4+δ).However,our extensive investigations reveal that this phenomenon is a novel insulatorto-metal transition,distinct from ***,compared to the weak magnetic-field effects,pressure can significantly suppress the transition and transform from the metallic to an insulating ground state,accompanied by an isostructural phase *** work not only elucidates the fundamental properties of the metallic conducting ground state in La_(N)iO_(4)+δ,but also critically challenges the notion of superconductivity in single-layer lanthanum nickelates.

关键词： resistance electrical metallic

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Grain size refinement of additive manufactured Ce-TZP ceramics by coupled two-step pre-sintering and HIP

引用

Journal of Advanced Ceramics 2024年第5期13卷 621-629页

作者： Ruoshi Zhao Hongbing Yang Xintong Liu Hezhen Li Chang-An Wang Jing Ma Yanhao Dong State key lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Ceria-stabilized tetragonal zirconia polycrystal(Ce-TZP)has exceptional fracture toughness and flaw tolerance due to facile t‒m phase transformation ***,its wider-range applications are limited by its relatively low strength due to its large grain size and low transformation stress,which results in yield-like ***,we combined additive manufacturing(AM),pressureless two-step sintering,and hot isostatic pressing(HIP),and addressed the challenging grain size refinement problem in *** successfully produced dense ultrafine-grained Ce-TZP ceramics with an average grain size below 500 nm,a three-point bending strength above 800 MPa,and a single-edge-notch-beam fracture toughness in the range of 11‒12 MPa·m^(1/2).The critical roles of processing design,mixed Ce valences,and ***-stabilization of tetragonal polymorphs were *** work offers insights and strategies for the future development of stronger and tougher Ce-TZP ceramics that can compete with tetragonal yttria-stabilized zirconia in various applications,including additive manufacturing.

关键词： zirconia additive manufacturing(AM) two-step sintering hot isostatic pressing(HIP) grain size refinement

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Negative enthalpy alloys and local chemical ordering:a concept and route leading to synergy of strength and ductility

引用

national Science Review 2024年第4期11卷 172-184页

作者： Zibing An Tao Yang Caijuan Shi Shengcheng Mao Lihua Wang Ang Li Wei Li Xianmeng Xue Ming Sun Yifan Bai Yapeng He Fuzeng Ren Zhouguang Lu Ming Yan Yang Ren Chain-Tsuan Liu Ze Zhang Xiaodong Han Beijing key lab of Microstructure and Property of Advanced materials College of Materials Science &Engineering Beijing University of Technology Department of materials Science and Engineering City University of Hong Kong key laboratory of Partial Acceleration Physics& Technology Institute of High Energy PhysicsChinese Academy of Sciences Department of materials Science &Engineering Southern University of Science and Technology Department of Physics City University of Hong Kong State key laboratory of Silicon materials Department of Materials Science and Engineering Zhejiang University

Solid solutions are ubiquitous in metals and alloys. Local chemical ordering(LCO) is a fundamental sub-nano/nanoscale process that occurs in many solid solutions and can be used as a microstructure to optimize strength and ductility. However, the formation of LCO has not been fully elucidated, let alone how to provide efficient routes for designing LCO to achieve synergistic effects on both superb strength and ductility. Herein, we propose the formation and control of LCO in negative enthalpy alloys. With engineering negative enthalpy in solid solutions, genetic LCO components are formed in negative enthalpy refractory high-entropy alloys(RHEAs). In contrast to conventional ‘trial-and-error' approaches, the control of LCO by using engineering negative enthalpy in RHEAs is instructive and results in superior strength(1160 MPa) and uniform ductility(24.5%) under tension at ambient temperature, which are among the best reported so far. LCO can promote dislocation cross-slip, enhancing the interaction between dislocations and their accumulation at large tensile strains; sustainable strain hardening can thereby be attained to ensure high ductility of the alloy. This work paves the way for new research fields on negative enthalpy solid solutions and alloys for the synergy of strength and ductility as well as new functions.

关键词： negative enthalpy alloys local chemical ordering strength ductility dislocation

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Solid-state synthesis of mesoporous metals via mechanochemical coordination self-assembly

引用

Science China Chemistry 2024年

作者： Hailong Xiong Chunyu Qi Lantian Xue Ling Zhang Hanyu Liu Zhen-An Qiao State key laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Hefei national Research Center for Physical Sciences at the Microscale University of Science and Technology of China State key laboratory of superhard materials College of Physics Jilin University State key laboratory of Supramolecular Structure and materials College of Chemistry Jilin University

Mesoporous metals with large surface area, high pore volume, and uniform pore structure hold excellent advantages for various applications. However, the state-of-the-art synthesis methods are still limited to wet chemistry, which requires excessive solvents and a time-consuming drying process. Here, we report a facile and general mechanochemical coordination self-assembly strategy to prepare mesoporous metals(e.g., Rh, Ru, Ir, Pt, Pd, Ag, Co, and Ni) with remarkable porous properties by using metal chlorides and cationic polymer interplay. Compared with the wet chemistry process, this method proceeds without solvents and does not need complicated experimental conditions and long synthetic periods, which not only greatly reduces the consumption of cost and energy and environmental pollution, but also improves the synthesis efficiency and yield of target products. We believe the developed approach will provide a general pathway for the scalable preparation of advanced porous materials.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Highly responsive broadband Si-based MoS2 phototransistor on high-k dielectric

引用

Science China(Information Sciences) 2024年第6期67卷 180-189页

作者： Ali IMRAN Xin HE Jiwei LIU Qinghai ZHU Muhammad SULAMAN Fei XUE Mingsheng XU Deren YANG College of Integrated Circuits State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University ZJU-Hangzhou Global Scientific and Technological Innovation Centre School of materials Science and Engineering State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University Beijing key lab of Nanophotonics and Ultrafine Optoelectronic Systems School of PhysicsBeijing Institute of Technology

The demand for photodetectors and image sensors has grown exponentially in the past decade in biomedical, security surveillance, robotics, automotive, quality control, image recognition, and military applications, due to their superior quality, broadband detection, lower noise, and economic viability. Here,we report a MoS2channel-based phototransistor over an HfO2/n-Si substrate isolated by an h BN layer. The high photoresponse is achieved through the integration of the photoconduction, photogating, and mobility enhancement process by utilizing excellent features of MoS2, HfO2/Si, and h BN. The capacitive coupling of the photogenerated carriers by high-k dielectric HfO2leads to modulation of MoS2Fermi level due to electrostatic doping. Furthermore, the MoS2also contributes to the photogeneration of carriers due to its semiconducting nature, leading to additional photocurrent. Ultimately, the combination of photogating,photoconduction, and swift carrier extraction with remarkable mobility of 11.65 cm2· V-1· s-1results in high responsivity, external quantum efficiency, and detectivity of 4.5 × 10～8A · W-1, 0.72 × 10～6, and 6.20× 1016Jones at 266 nm illumination, respectively. The device also demonstrates broadband photoresponse from 266–1000 nm wavelengths. The high responsivity distinguishes the potential of our device for the future of optoelectronics and broadband image sensing applications.

关键词： photogating photoconduction two-dimensional materials high k dielectric carrier scattering phototransistor

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

High-precision nondestructive evaluation of a thermal barrier coating based on perovskite quantum dot anion exchange

引用

Nano Research 2024年第5期17卷 4582-4592页

作者： Tao Han Shufang Ding Zifan Wang Sirong Jiang Pengjiang Jing Tianshang Yi Yaqi Chen Chunzhi Jiang Xiaofeng Zhang Microelectronics and Optoelectronics Technology key laboratory of Hunan Higher Education School of Physics and Electronic Electrical EngineeringXiangnan UniversityChenzhou 423000China national Engineering laboratory for Modern materials Surface Engineering Technology&The key lab of Guangdong for Modern Surface Engineering Technology Guangdong Institute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China

Thermal barrier coatings(TBCs)in gas turbine engines are used in expressly harsh environments;thus,assessing TBC integrity status is critical for safety and ***,traditional periodic maintenance involves visual inspections of the TBCs,requiring the gas turbine to be decommissioned and partially *** importantly,tiny defects or internal damages that easily cause coating failure cannot be *** this work,a new nondestructive evaluation(NDE)technique of TBCs based on quantum dot(QD)anion exchange is first explored *** exchanging anions between the Cl ions and the CsPbBr_(3) QDs,the degrees of salt corrosion of the TBCs are *** resultant NDE technique shows that the colour of the TBCs obviously changes from green to blue,accompanied by a large blueshift(~100 nm)of the photoluminescence(PL)peak *** addition,the relationship between the PL peak position and coating thermophysical properties indicates that the precision of this NDE technique may easily identify theμm-level of the thermal growth oxide(TGO)changes inside the TBCs.

关键词： thermal barrier coatings nondestructive evaluation CsPbBr_(3)quantum dot anion exchange thermal growth oxide

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

An all-metallic nanovesicle for hydrogen oxidation

引用

national Science Review 2024年第06期11卷 233-242页

作者： Juntao Zhang Lujie Jin Hao Sun Xiaozhi Liu Yujin Ji Youyong Li Wei Liu Dong Su Xuerui Liu Zhongbin Zhuang Zhiwei Hu Qi Shao Xiaoqing Huang State key laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Innovation laboratory for Sciences and Technologies of Energy materials of Fujian Province(IKKEM) key laboratory for Special Functional materials of Ministry of Education National &Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology School of Materials Science and EngineeringCollaborative Innovation Center of Nano Functional Materials and Applications Henan University Institute of Functional Nano and Soft materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials& Devices Soochow University State key laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Beijing national laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences State key lab of Organic-Inorganic Composites Beijing University of Chemical Technology Max Planck Institute for Chemical Physics of Solids College of Chemistry and Chemical Engineering and materials Science Soochow University

Vesicle, a microscopic unit that encloses a volume with an ultrathin wall, is ubiquitous in ***, it remains a huge challenge to create its inorganic metal-based artificial counterparts. Here,inspired by the formation of biological vesicles, we proposed a novel biomimetic strategy of curling the ultrathin nanosheets into nanovesicles, which was driven by the interfacial strain. Trapped by the interfacial strain between the initially formed substrate Rh layer and subsequently formed RhRu overlayer, the nanosheet begins to deform in order to release a certain amount of strain. Density functional theory（DFT）calculations reveal that the Ru atoms make the curling of nanosheets more favorable in thermodynamics applications. Owing to the unique vesicular structure, the RhRu nanovesicles/C displays excellent hydrogen oxidation reaction（HOR） activity and stability, which has been proven by both experiments and DFT calculations. Specifically, the HOR mass activity of RhRu nanovesicles/C are 7.52 A mg（Rh+Ru）-1at an overpotential of 50 m V at the rotating disk electrode（RDE） level; this is 24.19 times that of commercial Pt/C(0.31 m A mgPt-1). Moreover, the hydroxide exchange membrane fuel cell（HEMFC） with RhRu nanovesicles/C displays a peak power density of 1.62 W cm-2in the H2-O2condition, much better than that of commercial Pt/C(1.18 W cm-2). This work creates a new biomimetic strategy to synthesize inorganic nanomaterials, paving a pathway for designing catalytic reactors.

关键词： biomimetic synthesis nanovesicle interfacial strain hydrogen oxidation reaction

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Construct a 3D microsphere of HMX/B/Al/PTFE to obtain the high energy and combustion reactivity

引用

Defence Technology（防务技术） 2024年第2期32卷 45-54页

作者： Jian Wang Jie Chen Yaofeng Mao Yongjun Deng Wei Cao Fude Nie Jun Wang Institute of Chemical materials China Academy of Engineering PhysicsMianyang 621999PR China Shock and Vibration of Engineering materials and Structures key lab of Sichuan Province Mianyang 621010PR China

Metal(aluminum and boron)based energetic materials have been wildly applied in various fields including aerospace,explosives and micro-devices due to their high energy ***,the low combustion efficiency and reactivity of metal fuels,especially boron(B),severely limit their practical ***,multi-component 3D microspheres of HMX/B/Al/PTFE(HBA)have been designed and successfully prepared by emulsion and solvent evaporation method to achieve superior energy and combustion *** reactivity and energy output of HBA are systematically measured by ignitionburning test,constant-volume explosion vessel system and bomb *** to the increased interfacial contact and reaction area,HBA shows higher flame propagation rate,faster pressurization rate and larger combustion heat of 29.95 cm/s,1077 kPa/s,and 6164.43 J/g,which is 1.5 times,3.5 times,and 1.03 times of the physical mixed counterpart(HBA-P).Meanwhile,HBA also shows enhanced energy output and reactivity than 3D microspheres of HMX/B/PTFE(HB)resulting from the high reactivity of *** reaction mechanism of 3D microspheres is comprehensively investigated through combustion emission spectral and thermal analysis(TG-DSC-MS).The superior reactivity and energy of HBA originate from the surface etching of fluorine to the inert shell(Al_(2)O_(3) and B_(2)O_(3))and the initiation effect of Al to *** work offers a promising approach to design and prepare high-performance energetic materials for the practical applications.

关键词： HMX/B/Al/PTFE 3D microspheres Surface etching Reaction mechanism

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Regulation of pseudographitic carbon domain to boost sodium energy storage

引用

Nano Research 2024年第6期17卷 5188-5196页

作者： Zhidong Hou Mingwei Jiang Da Lei Xiang Zhang Yuyang Gao Jian-Gan Wang State key laboratory of Solidification Processing Center for Nano Energy MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical University and Shaanxi Joint Lab of Graphene(NPU)Xi’an 710072China

Hard carbon anode has shown extraordinary potentials for sodium-ion batteries(SIBs)owing to the cost-effectiveness and advantaged ***,the widespread application of hard carbon is still hindered by the insufficient sodium storage capacity and depressed rate property,which are mainly induced by the undesirable pseudographitic ***,we develop a molten-salt-mediated strategy to regulate the pseudographitic structure of hard carbon with suitable interlayer spacing and enlarged pseudographitic domain,which is conducive to the intercalation capacity and diffusion kinetics of sodium ***,the optimized hard carbon anode delivers a high reversible capacity of 320 mAh·g^(−1),along with superior rate property(138 mAh·g−1 at 2 A·g^(−1))and stable cyclability over 1800 ***,the in situ Raman spectroscopic study and full-cell assembly further investigate the sodium storage mechanism and practical implement of obtained hard *** work pioneers a low-cost and effective route to regulate the pseudographitic structure of hard carbon materials for advanced SIBs.

关键词： pseudographitic structure molten salt hard carbon anode sodium-ion batteries

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：