检索结果-南通市图书馆

Synthesis of covalent organic framework materials and their application in the field of sensing

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

Nano Research 2024年第1期17卷 162-195页

作者： Weiyu Zhang Shiwei Liu Qihua Sun Ning Tian Zhaofeng Wu Xinjiang Key Laboratory of solid-State physics and Devices Urumqi 830046China School of physics Science and Technology Xinjiang UniversityUrumqi 830046China

Covalent organic frameworks(COFs)are an emerging type of porous crystalline polymers formed by combining strong covalent bonds with organic building *** to their large surface area,high intrinsic pore space,good crystallization properties,high stability,and designability of the resultant units,COFs are widely studied and used in the fields of gas adsorption,drug transport,energy storage,photoelectric catalysis,electrochemistry,and *** recent years,the rapid development of the Internet of Things and people’s yearning for a better life have put forward higher and more requirements for sensors,which are the core components of the Internet of ***,this paper reviews the recent progress of COFs in synthesis methods and sensing applications,especially in the last five *** paper first introduces structure,properties,and synthesis methods of COFs and discusses advantages and disadvantages of different synthesis ***,the research progress of COFs in different sensing fields,such as metal ion sensors,gas sensors,biomedical sensors,humidity sensors,and pH sensors,is introduced *** and prospects are also presented in order to provide a reference for researchers concerned with COFs and sensors.

关键词： covalent organic framework materials structural design and synthesis sensing application gas sensors

Signature of Superconductivity in Pressurized La_(4)Ni_(3)O_(10)

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

Chinese physics Letters 2024年第1期41卷 77-84页

作者：李庆张英杰项浙宁张宇航祝熙宇闻海虎 National Laboratory of solid State Microstructures and Department of physics Center for Superconducting Physics and MaterialsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

The discovery of high-temperature superconductivity near 80K in bilayer nickelate La_(3)Ni_(2)O_(7)under high pressures has renewed the exploration of superconducting nickelate in bulk *** extension of superconductivity in other nickelates in a broader family is also ***,we report the experimental observation of superconducting signature in trilayer nickelate La_(4)Ni_(3)O_(10)under high *** using a modified solgel method and post-annealing treatment under high oxygen pressure,we successfully obtained polycrystalline La_(4)Ni_(3)O_(10)samples with different transport behaviors at ambient *** we performed high-pressure electrical resistance measurements on these samples in a diamond-anvil-cell ***,the signature of possible superconducting transition with a maximum transition temperature(T_(c))of about 20K under high pressures is observed,as evidenced by a clear drop of resistance and the suppression of resistance drops under magnetic *** the resistance drop is sample-dependent and relatively small,it appears in all of our measured *** argue that the observed superconducting signal is most likely to originate from the main phase of La_(4)Ni_(3)O_(10).Our findings will motivate the exploration of superconductivity in a broader family of nickelates and shed light on the understanding of the underlying mechanisms of high-T_(c) superconductivity in nickelates.

关键词： materials superconductivity signature

Ferromagnetism and insulating behavior with a logarithmic temperature dependence of resistivity in Pb_(10-x)Cux(PO_(4))_(6)O

在线全文

学校读者我要写书评

暂无评论

Science China(physics,Mechanics & Astronomy) 2024年第1期67卷 106-111页

作者： Yuhang Zhang Cong Liu Xiyu Zhu Hai-Hu Wen Center for Superconducting physics and Materials National Laboratory of Solid State Microstructures and Department of PhysicsNational Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

Recent claim of discovering above-room-temperature superconductivity(Tc≈400 K)at ambient pressure in copper doped apatite Pb10(PO_(4))_(6)O has stimulated world-wide enthusiasm and impulse of motion.A lot of follow-up works have been carried out with controversial *** check whether superconductivity is really present or absent in the material,we need samples which should have a rather pure phase of Pb_(10-x)Cux(PO_(4))_(6)*** we report the characterization results from the Pb_(10-x)Cux(PO_(4))_(6)O with a fraction of about 97 wt.%inferred from the fitting to the X-ray diffraction pattern,if assuming Cu2S as the only *** resistivity measurements show that it is a semiconductor characterized roughly by a ln(1/T)temperature dependence in wide temperature region without trace of *** measurements show that it has a general ferromagnetic signal with a weak superparamagnetic *** grains of the sample show clear interactions with a Nb Fe B *** detected Cu concentration is much lower than the expected nominal *** results show the absence of metallicity and superconductivity in Pb_(10-x)Cux(PO_(4))_(6)O at ambient pressure,and suggest the presence of strong correlation effect.

关键词： superconductivity Pb10(PO4)6O ferromagnetic correlation effect

Pion-photon and kaon-photon transition distribution amplitudes in the Nambu–Jona-Lasinio model

在线全文

学校读者我要写书评

暂无评论

Chinese physics C 2024年第8期48卷 94-103页

作者： Jin-Li Zhang Jun Wu Department of Mathematics and physics Nanjing Institute of TechnologyNanjing 211167China National Laboratory of solid State Microstructures Department of PhysicsNanjing UniversityNanjing 210093China

The Nambu–Jona-Lasinio model is utilized to investigate the pion-and kaon-photon leading-twist transition distribution amplitudes using proper time ***,the properties of the vector and axial vector pion-photon transition distribution amplitudes are examined,and the results meet the desired *** study involves sum rule and polynomiality *** vector and axial vector pion-photon transition form factors that are present in theπ^(+)→γe^(+)νprocess are the first Mellin moments of the pion-photon transition distribution *** vector transition form factor originates from the internal structure of hadrons,the axial current can be coupled to a pion,this pion is virtual,and its contribution will be present independently of the external *** kaon transition form factors are *** vector form factor's value at zero momentum transfer is determined by the axial anomaly,while this is not the case for the axial *** vector and axial form factors,as well as the neutral pion vector form factor F_(πγγ)(t),are *** to our findings,the pion axial transition form factor is harder than the vector transition form factor and harder than the electromagnetic form *** also discuss the link betweenπ−γandγ−πtransitions distribution amplitudes.

关键词： transition form factors NJL model transition distribution amplitudes

Mott Gap Filling by Doping Electrons through Depositing One Sub-Monolayer Thin Film of Rb on Ca_(2)CuO_(2)Cl_(2)

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

Chinese physics Letters 2024年第5期41卷 90-96页

作者：李寒王朝晖范圣泰李华州杨欢闻海虎 National Laboratory of solid State Microstructures and Department of physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

Understanding the doping evolution from a Mott insulator to a superconductor probably holds the key to resolve the mystery of unconventional superconductivity in copper oxides. To elucidate the evolution of the electronic state starting from the Mott insulator, we dose the surface of the parent phase Ca_(2)CuO_(2)Cl_(2) by depositing Rb atoms, which are supposed to donate electrons to the CuO_(2) planes underneath. We successfully achieved the Rb sub-monolayer thin films in forming the square lattice. The scanning tunneling microscopy or spectroscopy measurements on the surface show that the Fermi energy is pinned within the Mott gap but close to the edge of the charge transfer band. In addition, an in-gap state appears at the bottom of the upper Hubbard band(UHB), and the Mott gap will be significantly diminished. Combined with the Cl defect and the Rb adatom/cluster results, the electron doping is likely to increase the spectra weight of the UHB for the double occupancy. Our results provide information to understand the electron doping to the parent compound of cuprates.

关键词： doping holds Electron

Machine-learning-assisted efficient reconstruction of the quantum states generated from the Sagnac polarization-entangled photon source

在线全文

学校读者我要写书评

暂无评论

Chinese physics B 2024年第8期33卷 50-54页

作者：毛梦辉周唯李新慧杨然龚彦晓祝世宁 National Laboratory of solid State Microstructures and School of physics Nanjing UniversityNanjing 210093China Author notes

Neural networks are becoming ubiquitous in various areas of physics as a successful machine learning(ML)technique for addressing different *** on ML technique,we propose and experimentally demonstrate an efficient method for state reconstruction of the widely used Sagnac polarization-entangled photon *** properly modeling the target states,a multi-output fully connected neural network is well trained using only six of the sixteen measurement bases in standard tomography technique,and hence our method reduces the resource consumption without loss of *** demonstrate the ability of the neural network to predict state parameters with a high precision by using both simulated and experimental ***,the mean absolute error for all the parameters is below 0.05 for the simulated data and a mean fidelity of 0.99 is achieved for experimentally generated *** method could be generalized to estimate other kinds of states,as well as other quantum information tasks.

关键词： machine learning state estimation quantum state tomography polarization-entangled photon source

A deep learning interatomic potential suitable for simulating radiation damage in bulk tungsten

在线全文

学校读者我要写书评

暂无评论

Tungsten 2024年第2期6卷 304-322页

作者： Chang-Jie Ding Ya-Wei Lei Xiao-Yang Wang Xiao-Lin Li Xiang-Yan Li Yan-Ge Zhang Yi-Chun Xu Chang-Song Liu Xue-Bang Wu Key Laboratory of Materials physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Science Island University of Science and Technology of ChinaHefei 230026China Laboratory of Computational physics Institute of Applied Physics and Computational MathematicsBeijing 100088China

So far, it has been a challenge for existing interatomic potentials to accurately describe a wide range of physical properties and maintain reasonable efficiency. In this work, we develop an interatomic potential for simulating radiation damage in body-centered cubic tungsten by employing deep potential, a neural network-based deep learning model for representing the potential energy surface. The resulting potential predicts a variety of physical properties consistent with first-principles calculations, including phonon spectrum, thermal expansion, generalized stacking fault energies, energetics of free surfaces, point defects, vacancy clusters, and prismatic dislocation loops. Specifically, we investigated the elasticity-related properties of prismatic dislocation loops, i.e., their dipole tensors, relaxation volumes, and elastic interaction energies. This potential is found to predict the maximal elastic interaction energy between two 1/2 loops better than previous potentials, with a relative error of only 7.6%. The predicted threshold displacement energies are in reasonable agreement with experimental results, with an average of 128 eV. The efficiency of the present potential is also comparable to the tabulated gaussian approximation potentials and modified embedded atom method potentials, meanwhile, can be further accelerated by graphical processing units. Extensive benchmark tests indicate that this potential has a relatively good balance between accuracy, transferability, and efficiency.

关键词： Machine learning Deep learning Interatomic potential Radiation damage Tungsten

Mechanical Behavior and Microstructure Evolution during Tensile Deformation of Twinning Induced Plasticity Steel Processed by Warm Forgings

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 417-424页

作者：王文 ZHAO Modi WANG Xingfu 汪聃韩福生 School of Aerospace and Mechanical Engineering Flight College Changzhou Institute of TechnologyChangzhou 213032China Key Laboratory of Materials physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China School of physics and Electronic Information Yan’an UniversityYan’an 716000China

The mechanical behavior and microstructural evolution of an Fe-30Mn-3Al-3Si twinninginduced plasticity(TWIP)steel processed using warm forging was *** is found that steel processed via warm forging improves comprehensive mechanical properties compared to the TWIP steel processed via cold rolling,with a high tensile strength(R_(m))of 793 MPa,a yield strength(R_(P))of 682 MPa,an extremely large R_(P)/R_(m)ratio as high as 0.86 as well as an excellent elongation rate of 46.8%.The microstructure observation demonstrates that steel processed by warm forging consists of large and elongated grains together with fine,equiaxed *** micro-defect configurations were also observed within the steel,including dense dislocation networks and a few coarse deformation *** the plastic deformation proceeds,the densities of dislocations and deformation twins significantly ***,a great number of slip lines could be observed in the elongated *** findings reveal that a much more dramatic interaction between microstructural defect and dislocations glide takes place in the forging sample,wherein the fine and equiaxed grains propagated dislocations more rapidly,together with initial defect configurations,are responsible for enhanced strength ***,larger,elongated grains with more prevalently activated deformation twins result in high plasticity.

关键词： TWIP steel twinning mechanical property deformation mechanism microstructure

Large magnetostriction of Nd_(0.2)Tb_(0.3)Dy_(0.5)Fe_(1.93)/epoxy composites in a wide temperature range

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第4期42卷 705-709页

作者： Hehe Ding Yangguang Shi Shaolong Tang MIIT Key Laboratory of Aerospace Information Materials and physics Department of Applied PhysicsNanjing University of Aeronautics and AstronauticsNanjing210016China National Laboratory of solid State Microstructures Nanjing UniversityNanjing210093China

We report the magnetostrictive performance of the Nd_(0.2)Tb_(0.3)Dy_(0.5)Fe_(1.93)/epoxy *** of M?ssbauer spectra and the XRD results indicate that the easy magnetic direction of the Nd_(0.2)Tb_(0.3)Dy_(0.5)Fe_(1.93)compound is alongdirection with spontaneous magnetostrictionλ111 of1900 ***-oriented Nd_(0.2)Tb_(0.3)Dy_(0.5)Fe_(1.93)/epoxy composites with particle volume fractions of20 vol%-55 vol%were *** measurements demonstrate that the composite is highly *** raw material cost of Nd_(0.2)Tb_(0.3)Dy_(0.5)Fe_(1.93)is about 85%of that of the Terfenol-D(Tb_(0.3)Dy_(0.7)Fe_(2))***_(0.2)Tb_(0.3)Dy_(0.5)Fe_(1.93)/epoxy composites possess comparable magnetostriction with those composites made of Tb_(0.3)Dy_(0.7)Fe_(2)*** room temperature,the magnetostrictionλ_Ⅱof the Nd_(0.2)Tb_(0.3)Dy_(0.5)Fe_(1.93)/epoxy composite reaches 420 ppm at a low field of 80 kA/m and about1000 ppm at 239 kA/*** addition,the composite exhibits a large saturation magnetostrictionλ_Ⅱover1200 ppm from 300 to 100 K,suggesting its potential applications as a low-cost magnetostrictive material in a wide temperature ***,the current study offers an opportunity to widen the operating temperature range of the magnetostrictive composite.

关键词： Magnetostrictive composite Nd_(0.2)Tb_(0.3)Dy_(0.5)Fe_(1.93) Wide temperaturerange Laves phase Rare earths