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Universal dynamic scaling and Contact dynamics in quenched quantum gases

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Frontiers of physics 2024年第2期19卷 213-220页

作者： Jia-Nan Cui zhengqiang Zhou mingyuan Sun School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Lab of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China

Recently universal dynamic scaling is observed in several systems,which exhibit a spatiotemporal self-similar scaling behavior,analogous to the spatial scaling near phase transition.The latter one arises from the emergent continuous scaling symmetry.Motivated by this,we investigate the possible relation between the scaling dynamics and the continuous scaling symmetry in this paper.We derive a theorem that the scaling invariance of the quenched Hamiltonian and the initial density matrix can lead to the universal dynamic scaling.It is further demonstrated both in a two-body system analytically and in a many-body system numerically.For the latter one,we calculate the dynamics of quantum gases quenched from the zero interaction to a finite interaction via the non-equilibrium high-temperature virial expansion.A dynamic scaling of the momentum distribution appears in certain momentum-time windows at unitarity as well as in the weak interacting limit.Remarkably,this universal scaling dynamics persists approximately with smaller scaling exponents even if the scaling symmetry is fairly broken.Our findings may offer a new perspective to interpret the related experiments.We also study the Contact dynamics in the BEC−BCS crossover.Surprisingly,the half-way time displays a maximum near unitarity while some damping oscillations occur on the BEC side due to the dimer state,which can be used to detect possible two-body bound states in experiments.

关键词： dynamic scaling Contact dynamics quantum gases cold atom quench dynamics virial expansion continuous scaling symmetry

The role of snapin in regulation of brain homeostasis

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Neural Regeneration Research 2024年第8期19卷 1696-1701页

作者： Jiawen Li Xinqi Huang Yumei An Xueshi Chen Yiyang Chen mingyuan Xu Haiyan Shan Mingyang Zhang Shanghai Key Lab of Forensic Medicine Key Lab of Forensic ScienceMinistry of JusticeChina(Academy of Forensic Science)ShanghaiChina Institute of Forensic Sciences Suzhou Medical CollegeSoochow UniversitySuzhouJiangsu ProvinceChina Department of Obstetrics and Gynecology The Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhouJiangsu ProvinceChina

Brain homeostasis refe rs to the normal working state of the brain in a certain period,which is impo rtant for overall health and normal life activities.Currently,there is a lack of effective treatment methods for the adverse consequences caused by brain homeostasis imbalance.Snapin is a protein that assists in the formation of neuronal synapses and plays a crucial role in the normal growth and development of synapses.Recently,many researchers have reported the association between snapin and neurologic and psychiatric disorders,demonstrating that snapin can improve brain homeostasis.Clinical manifestations of brain disease often involve imbalances in brain homeostasis and may lead to neurological and behavioral sequelae.This article aims to explo re the role of snapin in restoring brain homeostasis after injury or diseases,highlighting its significance in maintaining brain homeostasis and treating brain diseases.Additionally,it comprehensively discusses the implications of snapin in other extracerebral diseases such as diabetes and viral infections,with the objective of determining the clinical potential of snapin in maintaining brain homeostasis.

关键词： brain homeostasis diabetes neurological diseases snapin traumatic brain injury vesicle fusion

Small tracking error correction for moving targets of intelligent electro-optical detection systems

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Frontiers of Mechanical Engineering 2024年第2期19卷 29-44页

作者： Cheng SHEN Zhijie WEN Wenliang ZHU Dapeng FAN mingyuan LING College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China

Small tracking error correction for electro-optical systems is essential to improve the tracking precision of future mechanical and defense technology.Aerial threats,such as“low,slow,and small(LSS)”moving targets,pose increasing challenges to society.The core goal of this work is to address the issues,such as small tracking error correction and aiming control,of electro-optical detection systems by using mechatronics drive modeling,composite velocity–image stability control,and improved interpolation filter design.A tracking controller delay prediction method for moving targets is proposed based on the Euler transformation model of a two-axis,two-gimbal cantilever beam coaxial configuration.Small tracking error formation is analyzed in detail to reveal the scientific mechanism of composite control between the tracking controller’s feedback and the motor’s velocity–stability loop.An improved segmental interpolation filtering algorithm is established by combining line of sight(LOS)position correction and multivariable typical tracking fault diagnosis.Then,a platform with 2 degrees of freedom is used to test the system.An LSS moving target shooting object with a tracking distance of S=100 m,target board area of A=1 m^(2),and target linear velocity of v=5 m/s is simulated.Results show that the optimal method’s distribution probability of the tracking error in a circle with a radius of 1 mrad is 66.7%,and that of the traditional method is 41.6%.Compared with the LOS shooting accuracy of the traditional method,the LOS shooting accuracy of the optimized method is improved by 37.6%.

关键词： electro-optical detection system small tracking error moving target visual servo aiming contro

Mitochondria-specific near-infrared photoactivation of peroxynitrite upconversion luminescent nanogenerator for precision cancer gas therapy

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Acta Pharmaceutica Sinica B 2024年第1期14卷 378-391页

作者： Hui Yu Aliya Tiemuer Xufeng Yao mingyuan Zuo Hai-Yan Wang Yi Liu Xiaoyuan Chen Department of Biomedical Engineering School of EngineeringChina Pharmaceutical UniversityNanjing 211198China School of Mechanical Engineering Southeast UniversityNanjing 211189China Departments of Diagnostic Radiology SurgeryChemical and Biomolecular Engineeringand Biomedical EngineeringYong Loo Lin School of Medicine and College of Design and EngineeringNational University of SingaporeSingapore 119074Singapore Clinical Imaging Research Centre Centre for Translational MedicineYong Loo Lin School of MedicineNational University of SingaporeSingapore 117599Singapore Nanomedicine Translational Research Program Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore Institute of Molecular and Cell Biology Agency for ScienceTechnologyand Research(A*STAR)ProteosSingapore 138673Singapore

Gas therapy is emerging as a highly promising therapeutic strategy for cancer treatment.However,there are limitations,including the lack of targeted subcellular organelle accuracy and spatiotemporal release precision,associated with gas therapy.In this study,we developed a series of photoactivatable nitric oxide(NO)donors NRh-R-NO(R=Me,Et,Bn,iPr,and Ph)based on an N-nitrosated upconversion luminescent rhodamine scaffold.Under the irradiation of 808 nm light,only NRh-Ph-NO could effectively release NO and NRh-Ph with a significant turn-on frequency upconversion luminescence(FUCL)signal at 740 nm,ascribed to lower N-N bond dissociation energy.We also investigated the involved multistage near-infrared-controlled cascade release of gas therapy,including the NO released from NRh-Ph-NO along with one NRh-Ph molecule generation,the superoxide anion O_(2)^(⋅−)produced by the photodynamic therapy(PDT)effect of NRh-Ph,and highly toxic peroxynitrite anion(ONOO‒)generated from the co-existence of NO and O_(2)^(⋅−).After mild nano-modification,the nanogenerator(NRh-Ph-NO NPs)empowered with superior biocompatibility could target mitochondria.Under an 808 nm laser irradiation,NRh-Ph-NO NPs could induce NO/ROS to generate RNS,causing a decrease in the mitochondrial membrane potential and initiating apoptosis by caspase-3 activation,which further induced tumor immunogenic cell death(ICD).In vivo therapeutic results of NRh-Ph-NO NPs showed augmented RNS-potentiated gas therapy,demonstrating excellent biocompatibility and effective tumor inhibition guided by real-time FUCL imaging.Collectively,this versatile strategy defines the targeted RNS-mediated cancer therapy.

关键词： Near infrared Photo-triggered Mitochondrion Upconversion luminescent bioimaging Peroxynitrite Nanogenerator Gas therapy In vivo

Cobalt-nanoparticle catalysts derived from zeolitic imidazolate framework@MXene composites for efficient oxidative self-coupling of benzylamines

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Frontiers of Chemical Science and Engineering 2024年第1期18卷 95-106页

作者： Jie Chen mingyuan Jian Deqiong Xie Kecan Dou Deli Chen Weidong Zhu Fumin Zhang Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China

In this study,we synthesize a catalyst comprising cobalt nanoparticles supported on MXene by pyrolyzing a composite in a N2 environment.Specifically,the composite comprises a bimetallic Zn/Co zeolitic imidazole framework grown in situ on the outer surface of MXene.The catalytic efficiency of the catalyst is tested for the self-coupling of 4-methoxybenzylamine to produce value-added imine,where atmospheric oxygen(1 atm)is used as the oxidant.Based on the results,the catalyst displayed impressive catalytic activity,achieving 95.4%yield of the desired imine at 383 K for 8 h.Furthermore,the catalyst showed recyclability and tolerance toward benzylamine substrates with various functional groups.The outstanding performance of the catalyst is primarily attributed to the synergetic catalytic effect between the cobalt nanoparticles and MXene support,while also benefiting from the three-dimensional porous structure.Additionally,a preliminary investigation of potential reaction mechanisms is conducted.

关键词： MXene sacrificial template oxidative self-coupling Co nanoparticles imine

Low-frequency oscillation of train-network system considering traction power supply mode

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Railway Engineering Science 2024年第2期32卷 244-256页

作者： Yuchen Liu Xiaoqin Lyu mingyuan Chang Qiqi Yang School of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031China

The low-frequency oscillation(LFO)has occurred in the train-network system due to the introduction of the power electronics of the trains.The modeling and analyzing method in current researches based on electrified railway unilateral power supply system are not suitable for the LFO analysis in a bilateral power supply system,where the trains are supplied by two traction substations.In this work,based on the single-input and single-output impedance model of China CRH5 trains,the node admittance matrices of the train-network system both in unilateral and bilateral power supply modes are established,including three-phase power grid,traction transformers and traction network.Then the modal analysis is used to study the oscillation modes and propagation characteristics of the unilateral and bilateral power supply systems.Moreover,the influence of the equivalent inductance of the power grid,the length of the transmission line,and the length of the traction network are analyzed on the critical oscillation mode of the bilateral power supply system.Finally,the theoretical analysis results are verified by the time-domain simulation model in MATLAB/Simulink.

关键词： Low-frequency oscillation Train-network system Modal analysis Bilateral power supply Participation factor

Unlocking single-atom catalysts via amorphous substrates

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Nano Research 2024年第5期17卷 3533-3546页

作者： Bohua Sun mingyuan Xu Xiaoxia Li Baohong Zhang Rui Hao Xiaoyu Fan Binbin Jia Dingshun She School of Engineering and Technology China University of Geosciences(Beijing)Beijing 100083China zhengzhou Institute China University of Geosciences(Beijing)Zhengzhou 451283China College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China School of Chemistry Beihang UniversityBeijing 100191China Chinese Academy of Sciences(CAS)Key Laboratory of Nanosystem and Hierarchy Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China National Engineering Research Center of Nonferrous Metals Materials and Products for New EnergyChina GRINM Group Co.Ltd.Beijing 100088China

Single-atom catalysts(SACs)reveal great potential for application in catalysis due to their fully exposed active sites.In general,single atoms(SAs)and the coordination substrates need to have strong interactions or charge transfer to ensure the atomic dispersion,which requires the selection of a suitable substrate to stabilize the target atoms.Recent studies have demonstrated that amorphous materials with abundant defects and coordinatively unsaturated sites can be used as substrates for more efficient capturing SAs,further enhancing the catalytic performance.In this review,we discuss recent research progress of SAs loaded on amorphous substrates for enhanced catalytic activity.Firstly,we summarize the commonly used amorphous substrates for stabilizing SAs.Subsequently,we present several advanced applications of amorphous SACs in the field of catalysis,including electrocatalysis and photocatalysis.And then,we also clarify the synergistic mechanism between SAs and amorphous substrate on catalytic process.Finally,we summarize the challenges with our personal views and provide a critical outlook on how amorphous SACs continue to evolve.

关键词： single-atoms amorphous substrate synthetic strategy catalysis

Active and stable Cu doped NiMgAlO catalysts for upgrading ethanol to n-butanol

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Journal of Energy Chemistry 2022年第9期31卷 306-317,I0009页

作者： Zhinuo Wang Ming Yin Jifeng Pang Xianquan Li Yanan Xing Yang Su Shimin Liu Xiaoyan Liu Pengfei Wu mingyuan zheng Tao Zhang CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116028LiaoningChina Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023LiaoningChina

Upgrading ethanol to n-butanol is an attractive way for renewable n-butanol production. Herein, Cu was selected to modify NiMgAlO catalysts for improving ethanol conversion and n-butanol selectivity. Over the optimized 2%Cu-NiMgAlO catalyst, ethanol conversion and n-butanol selectivity were enhanced to 30.0% and 64.2%, respectively, in 200 h time on stream at 523 K. According to physicochemical characterizations and theoretical calculations, the key role of multiple active sites in this reaction was extensively investigated. The plate-like structure of hydrotalcite was maintained over 2%Cu-NiMgAlO catalysts, with an average Ni particle size of ca. 5.4 nm. The presence of Cu species created CuNi alloy sites and Lewis acid-base pairs, and increased hydrogen transfer and condensation reactions, resulting in elevated ethanol conversion and n-butanol selectivity. Additionally, CuNi alloy had a strong interaction with CuNiMgAl oxides, forming homogeneous boundary due to their close ionic radius and lattice matching, and afforded the long time stability in the ethanol to n-butanol reaction.

关键词： Hydrotalcite Copper Catalysis Ethanol n-Butanol

An efficient recycling strategy to eliminate the residual“impurities”while heal the damaged structure of spent graphite anodes

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Green Energy & Environment 2024年第6期9卷 1027-1034页

作者： Dan Yang Ying Yang Haoran Du Yongsheng Ji mingyuan Ma Yujun Pan Xiaoqun Qi Quan Sun Kaiyuan Shi Long Qie Institute of New Energy for Vehicles School of Materials Science and EngineeringTongji UniversityShanghai201804China State Key Laboratory of Material Processing and Die&Mold Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China Shuangdeng Group Co. Ltd.Taizhou225500China School of Materials Science and Engineering Sun Yat-Sen UniversityGuangzhou510275China

The recycling of graphite from spent lithium-ion batteries(LIBs)is overlooked due to its relatively low added value and the lack of efficient recovering methods.To reuse the spent graphite anodes,we need to eliminate their useless components(mainly the degraded solid electrolyte interphase,SEI)and reconstruct their damaged structure.Herein,a facile and efficient strategy is proposed to recycle the spent graphite on the basis of the careful investigation of the composition of the cycled graphite anodes and the rational design of the regeneration processes.The regenerated graphite,which is revitalized by calcination treatment and acid leaching,delivers superb rate performance and a high specific capacity of 370 mAh g^(-1)(~99% of its theoretical capacity)after 100 cycles at 0.1 C,superior to the commercial graphite anodes.The improved electrochemical performance could be attributed to unchoked Li^(+) transport channels and enhanced charge transfer reaction due to the effective destruction of the degraded SEI and the full recovery of the damaged structure of the spent graphite.This work clarifies that the electrochemical performance of the regenerated graphite could be deteriorated by even a trace amount of the residual“impurity”and provides a facile method for the efficient regeneration of graphite anodes.

关键词： Graphite Anode Regeneration Solid electrolyte interphase Spent lithium-ion battery