检索结果-南通市图书馆

National Science Review 2024年第4期11卷 195-205页

作者： Yanhua Wan Changyao Wang Xingmiao Zhang Yang Yin Mengmeng Liu Bing Ma Linlin Duan Yuzhu Ma Wei Zhang Changlin Zheng Dongliang Chao Fei Wang Yongyao Xia Wei Li department of chemistry Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials State Key Laboratory of Molecular Engineering of Polymers College of Chemistry and Materials ScienceFudan University State Key Laboratory of Surface physics and department of physics Fudan University

Due to their uncontrollable assembly and crystallization process,the synthesis of mesoporous metal oxide single crystals remains a formidable ***,we report the synthesis of single-crystal-like mesoporous Li2TiSiO5by using soft micelles as *** key lies in the atomic-scale self-assembly and step-crystallization processes,which ensure the formation of single-crystal-like mesoporous Li2TiSiO5microparticles via an oriented attachment growth mechanism under the confinement of an in-situ formed carbon *** mesoporous Li2TiSiO5anode achieves a superior rate capability(148 mAh g-1at5.0 A g-1) and outstanding long-term cycling stability(138 mAh g-1after 3000 cycles at 2.0 A g-1) for lithium storage as a result of the ultrafast Li+diffusion caused by penetrating mesochannels and nanosized crystal frameworks（5-10 nm）.In comparison,bulk Li2TiSiO5exhibits poor rate capability and cycle performance due to micron-scale diffusion *** method is very simple and reproducible,heralding a new way of designing and synthesizing mesoporous single crystals with controllable frameworks and chemical functionalities.

关键词： mesoporous materials micelles single-crystal-like Li2TiSiO5 lithium-ion batteries

Anisotropic Mechanical Response of Nacre to Heat Treatment Under Indentation:Effect of Structural Orientation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2024年第3期21卷 1453-1464页

作者： Simin Liang Yingying Li Hongmei Ji Xiaowu Li department of materials physics and chemistry School of Materials Science and EngineeringKey Laboratory for Anisotropy and Texture of MaterialsMinistry of EducationNortheastern UniversityShenyang110819China

It is generally considered that heat treatments have a negative impact on the mechanical properties of nacre due to thermal decomposition of the organic ***,the present work investigated the microindentation behavior on fresh and heat-treated nacres from two orthogonal directions,and the results demonstrate that both hardness value and damage tolerance can remain almost unchanged on the cross-section with the organic matrix degeneration,despite a significant deterioration on the platelet *** analyses suggest that the anisotropic response of indentation behavior to heat treatment in nacre is primarily caused by its structural ***,compared with a single layer of irregular interplatelet interfaces in cross-sectional specimens,the multiple layers of parallel interlamellar interfaces in in-plane specimens exhibit a much greater ability to impede indenter-triggered destruction,and heat treatments would reduce the in-plane hardness but nearly have no effect on the cross-sectional ***,the deeper embedding of platelets in cross-sectional specimens enhances their resistance to interface cracking caused by organic matrix degradation at high temperatures,leading to a reduced sensitivity to ***,the indentation behavior of nacre shows different tendencies in response to variations in the organic matrix state along normal and parallel directions.

关键词： Nacre Structural orientation Heat treatment Indentation behavior Organic matrix

Doping engineering of iron oxide nanoparticles towards high performance and biocompatible T_(1)-weighted MRI contrast agents

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第1期43卷 298-308页

作者： Xue Xu Ping-Li Dong Yu-Yun Chai Run Yang Zhen-Hui Ma Chi-Chong Lu department of chemistry College of Chemistry and Materials EngineeringBeijing Technology and Business UniversityBeijing 100048China department of physics Beijing Technology and Business UniversityBeijing 100048China

Extremely small-sized iron oxide nanoparticles(IONPs) are of great interest in magnetic resonance imaging(MRI) due to their biosafety as an alternative to clinical gadolinium(Ⅲ) complexes-based contrast *** when the particle size is less than 10 nm,it has strong diffusion ability and deep penetration distance in tumor *** doping can significantly enhance the T_(1)contrast effect of nanoparticles by regulating the surface exposed ***,the nucleation and growth processes of multi-component synthesis systems are complex and difficult to be accurately controlled,leading to great challenges in the synthesis of ultra-small-sized nanoparticles with different components and ***,extremely smallsized superparamagnetic gadolinium-doped iron oxide nanoparticles(GdIONPs,Gd_(x)Fe_(3-x)O_(4) NPs) with adjustable doping amount and controllable size in the range of 3.5-7.5 nm were synthesized by thermal ***,as-synthesized GdIONPs were surface modified with a highly water-soluble and biocompatible carboxyl-polyethylene glycol-phosphoric acid ligand with high binding ***_(0.65)Fe_(2.35)O_(4) NPs exhibited very high r_(1) relaxivity of 10.6 mmol^(-1)·L·s^(-1) in terms of all metal concentrations and 49.0 mmol^(-1)·L·s^(-1) in terms of gadolinium alone,respectively,3 and 14 times higher than clinical T_(1) contrast agents(Gd-DTPA).GdIONPs can continuously obtain high resolution images of blood vessels,and can be used as an efficient and multifunctional contrast agent for MR T_(1)*** stable and efficient doping strategy provides an easy and effective method to individually optimize the magnetic properties of complex oxides and their relaxation effects for a variety of biomedical applications.

关键词： Iron oxide nanoparticles Small size Magnetic resonance imaging Substitutional doping Gd dopant

维普期刊数据库

Simple chemical synthesis and isotropic negative thermal expansion in MHfF_(6)(M=Ca,Mn,Fe,and Co)

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 2195-2203页

作者： Yongqiang Qiao Sen Zhang Peixian Zhang Juan Guo Andrea Sanson Xi Zhen Kaiyue Zhao Qilong Gao Jun Chen Key Laboratory of materials physics of Ministry of Education and School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China department of physics and Astronomy University of PadovaPadova I-35131Italy Beijing Advanced Innovation Center for materials Genome Engineering Department of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China

The rapid progress of modern technologies has accelerated the prominence of thermal expansion mismatch between materials,and tunable thermal expansion materials will be a powerful safeguard against this ***,isotropic MHfF_(6)(M=Ca,Mn,Fe,and Co)compounds with tunable thermal expansion have been produced via a low-cost synthetic method and *** utilizing temperature dependent X-ray diffraction(XRD)and Raman spectroscopy,combined with first principles calculations,it was revealed that the transverse thermal vibrations of the F atoms are dominated by low-frequency phonons with negative Grüneisen parameters and are therefore the origin of the negative thermal expansion(NTE).Very interestingly,with the increase of the M atomic number,the metal…F atomic linkages become stiffer,reducing the number of vibrational modes with negative Grüneisen parameters,so that the strong NTE can be gradually adjusted to moderate NTE and to near zero thermal *** present study achieves the tunable thermal expansion in a new compound family and shed light on the internal mechanism from the perspective of lattice vibrational dynamics.

关键词： negative thermal expansion fluorides chemical synthesis nanosheet structure first principles calculations

Coordination environments build up and tune a superior synergistic “genome” toward novel trifunctional (TM-N_(x)O_(4−x))@g- C_(16)N_(3)-H_(3): High-throughput inspection of ultra-high activity for water splitting and oxygen reduction reactions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第4期17卷 2337-2351页

作者： Chunyao Fang Xian Wang Qiang Zhang Xihang Zhang Chenglong Shi Jingcheng Xu Mengyu Yang department of physics University of Shanghai for Science and TechnologyShanghai 200093China School of materials and chemistry University of Shanghai for Science and TechnologyShanghai 200093China

Emerging as a prominent area of focus in energy conversion and storage technologies,the development of highly active metal-based single-atom catalysts(SACs)holds great signiﬁcance in searching alternatives to replace precious metals toward the efficient,stable,and low-cost hydrogen evolution reaction(HER),as well as the oxygen evolution reaction(OER)and the oxygen reduction reaction(ORR).Combining the tremendous tunability of ligand and coordination environment with rich metal-based electrocatalysts can create breakthrough opportunities for achieving both high stability and ***,we propose a novel and stable holey graphene-like carbon nitride monolayer g-C_(16)N5(N_(4)@g-C_(16)N_(3))stoichiometries interestingly behaving as a natural substrate for constructing SACs((TM-N_(4))@g-C_(16)N_(3)),whose evenly distributed holes map rich and uniform nitrogen coordination positions with electron-rich lone pairs for anchoring transition metal(TM)***,we employed density functional theory(DFT)calculations to systematically investigate the electrocatalytic activity of(TM-N_(4))@g-C_(16)N_(3) toward HER/OER/ORR,meanwhile considering the synergistic modulation of H-loading and O-coordination((TM-N_(x)O_(4-x))@g-C_(16)N_(3)^(-)H_(3),x=0–4).Together a“four-step procedure”screening mechanism with the first-principles high-throughput calculations,we find that(Rh-N_(4))and(Ir-N_(2)O_(2)-II)distributed on g-C_(16)N_(3)^(-)H_(3) can modulate the adsorption strength of the adsorbates,thus achieving the best HER/OER/ORR performance among 216 candidates,and the lowest overpotential of 0.098/0.3/0.46 V and 0.06/0.48/0.45 V,***,the d-band center,crystal orbital Hamilton population(COHP),and molecular orbitals are used to reveal the OER/ORR activity ***,the Rh/Ir-d orbital is dramatically hybridized with the O-p orbital of the oxygenated adsorbates,so that the lone-electrons incipiently locate at the antibonding orbital pair up and popula

关键词： single atom catalysts loading and coordination hydrogen evolution reaction oxygen evolution reaction oxygen reduction reaction

Morphology Study for GeV Emission of Nearby Supernova Remnant G332.5-5.6

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第4期24卷 134-140页

作者： Ming-Hong Luo Qing-Wen Tang Xiu-Rong Mo department of physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China

A spatial template is important to study nearby supernova remnants(SNRs).For SNR G332.5-5.6,we report a Gaussian disk with a radius of about 1°.06 to be a potential good spatial model in the γ-ray *** this new Gaussian disk,its GeV lightcurve shows a significant variability of about seven *** γ-ray observations of this SNR could be explained well either by a leptonic model or a hadronic model,in which a flat spectrum for the ejected electrons/protons is required.

关键词： ISM:supernova remnants gamma rays:ISM

维普期刊数据库

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

在线全文

学校读者我要写书评

暂无评论

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

Counterion-Mediated Hydrogen Bonding Making Strong Polyelectrolytes pH-Responsive:Current Understanding and Perspectives

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第9期42卷 1270-1277,I0005页

作者： Yue Huang Guang-Tao Mei Zan Hua Guang-Ming Liu Hefei National Research Center for Physical Sciences at the Microscale Department of Chemical PhysicsKey Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education InstitutesUniversity of Science and Technology of ChinaHefei230026China The Key Laboratory of Functional Molecular Solids Ministry of Educationand Department of Materials ChemistrySchool of Chemistry and Materials ScienceAnhui Normal UniversityWuhu214002China

The counterion-mediated hydrogen bonding(CMHB)is related to the hydrogen bonding between bound counterions and polyelectrolyte chains in polyelectrolyte systems,where the counterions can both electrostatically bind to the charged groups of polyelectrolyte chains and act as hydrogen bond donors or acceptors to form hydrogen bonds with the hydrogen bond sites associated with polyelectrolyte chains simultaneously.A large number of literatures illustrate that strong polyelectrolytes(SPs)are insensitive to pH,which severely limmits the applications of SPs as smart ***,our studies have demonstrated that the CMHB makes SPs *** perspective discusses the mechanism of pH responsiveness of SPs and the pH-tunable properties of SPs,based on the pH-controlled CMHB *** future research directions on the pH responsiveness of SPs are also discussed *** is anticipated that the study of the pH responsiveness of SPs not only will provide a new understanding of the fundamental properties of SPs,but also will greatly expand the applications of SPs in the field of smart materials.

关键词： Counterion binding Hydrogen bond Polyelectrolyte brush Polyelectrolyte complexation

Soft multifunctional neurological electronic skin through intrinsically stretchable synaptic transistor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第7期17卷 6550-6559页

作者： Pengcheng Zhu Shuairong Mu Wenhao Huang Zeye Sun Yuyang Lin Ke Chen Zhifeng Pan Mohsen Golbon Haghighi Roya Sedghi Junlei Wang Yanchao Mao Key Laboratory of materials physics of Ministry of Education School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450001China department of chemistry Shahid Beheshti UniversityTehran ***Iran

Neurological electronic skin(E-skin)can process and transmit information in a distributed manner that achieves effective stimuli perception,holding great promise in neuroprosthetics and soft *** E-skin with multifunctional perception abilities can enable robots to precisely interact with the complex surrounding ***,current neurological E-skins that possess tactile,thermal,and visual perception abilities are usually prepared with rigid materials,bringing difficulties in realizing biologically synapse-like ***,we report a soft multifunctional neurological E-skin(SMNE)comprised of a poly(3-hexylthiophene)(P3HT)nanofiber polymer semiconductor-based stretchable synaptic transistor and multiple soft artificial sensory receptors,which is capable of effectively perceiving force,thermal,and light *** stretchable synaptic transistor can convert electrical signals into transient channel currents analogous to the biological excitatory postsynaptic *** it also possesses both short-term and long-term synaptic plasticity that mimics the human memory *** integrating a stretchable triboelectric nanogenerator,a soft thermoelectric device,and an elastic photodetector as artificial receptors,we further developed an SMNE that enables the robot to make precise actions in response to various surrounding *** with traditional neurological E-skin,our SMNE can maintain the softness and adaptability of biological synapses while perceiving multiple stimuli including force,temperature,and *** SMNE could promote the advancement of E-skins for intelligent robot applications.

关键词： electronic skin soft stretchable polymer semiconductor synaptic transistor multifunctional

Record-high efficiency perovskite LEDs achieved by accelerating radiative recombination

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China materials 2024年第9期67卷 3039-3040页

作者： Feng Gao department of physics Chemistry and BiologyLink?ping University

Light-emitting diodes(LEDs) have revolutionized the lighting and displays due to their superior energy efficiency. The increasing demand for more efficient and brighter thin-film LEDs in flat-panel displays and solid-state lighting applications has driven extensive research into perovskite materials, which show great promise for high brightness and efficiency.

关键词：

同方期刊数据库