检索结果-南通市图书馆

基于玻色凝聚^(87)Rb原子气体相位Ramsey干涉的磁场探测

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

深圳大学学报（理工版） 2024年第5期41卷 517-523页

作者：吴嘉涛方瑞环韩成银马翥詹畅李懋捷黄嘉豪鹿博李朝红中山大学物理与天文学院量子工程与精密测量实验室广东珠海519082 深圳大学量子精密测量研究所物理与光电工程学院射频异质异构集成全国重点实验室广东深圳518060 粤港澳大湾区量子科学中心广东深圳518045

基于玻色凝聚原子气体的磁场探测可兼顾高灵敏度和高空间分辨率.利用一维光晶格中玻色凝聚^(87)Rb原子气体F=1,m_(F)=1→F=2,m_(F)=-1(F为原子总角动量的量子数,m_(F)为F能级的磁量子数)的双光子跃迁,已实现基于相位Ramsey干涉的精密磁... 详细信息

基于玻色凝聚原子气体的磁场探测可兼顾高灵敏度和高空间分辨率.利用一维光晶格中玻色凝聚^(87)Rb原子气体F=1,m_(F)=1→F=2,m_(F)=-1(F为原子总角动量的量子数,m_(F)为F能级的磁量子数)的双光子跃迁,已实现基于相位Ramsey干涉的精密磁场探测.本研究利用交叉光阱中玻色凝聚^(87)Rb原子气体F=1,m_(F)=1→F=2,m_(F)=0的单光子跃迁,实验研究了频域Ramsey干涉、时域Ramsey干涉及相位Ramsey干涉,并基于相位Ramsey干涉评估了静态磁场测量的灵敏度和空间分辨率.通过对比上述3种Ramsey干涉的实验结果,发现相位Ramsey干涉可有效避免频域Ramsey干涉条纹的畸变和时域Ramsey干涉的退相干效应,从而提高静态磁场测量的灵敏度和准确度.在无磁屏蔽环境中,利用体积为(1.31±0.03)×10^(-9)cm^(3)的玻色凝聚^(87)Rb原子气体,获得了130 nT/√Hz的灵敏度,通过压缩原子气体制备时间和提高信号积累时间,灵敏度有望得到进一步提升.

关键词：光学 Ramsey光谱光学泵浦原子激光冷却与囚禁玻色凝聚原子气体精密磁场探测

Production of ^(87)Rb Bose-Einstein Condensate in an Asymmetric Crossed Optical Dipole Trap

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2021年第10期38卷 12-16页

作者： Zhu Ma chengyin han Xunda Jiang Ruihuan Fang Yuxiang Qiu Minhua Zhao Jiahao Huang Bo Lu Chaohong Lee Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing&School of Physics and Astronomy Sun Yat-Sen University(Zhuhai Campus)State Key Laboratory of Optoelectronic Materials and TechnologiesSun Yat-Sen University(Guangzhou Campus)Zhuhai 519082China State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-Sen University(Guangzhou Campus)Guangzhou 510275China

We report the production of ^(87)Rb Bose–Einstein condensate in an asymmetric crossed optical dipole trap(ACODT)without the need of an additional dimple *** our experiment,the ACODT is formed by two laser beams with different radii to achieve efficient capture and rapid evaporation of laser cooled *** to the cooling procedure in a magnetic trap,the atoms are firstly laser cooled and then directly loaded into an ACODT without the pre-evaporative cooling *** order to determine the optimal parameters for evaporation cooling,we optimize the power ratio of the two beams and the evaporation time to maximize the final atom number left in the *** loading about 6×10^(5) laser cooled atoms in the ACODT,we obtain a pure Bose–Einstein condensate with about 1.4×10^(4) atoms after 19 s ***,we demonstrate that the fringe-type noises in optical density distributions can be reduced via principal component analysis,which correspondingly improves the reliability of temperature measurement.

关键词： measurement Einstein Bose

The effect of salt anion in ether‐based electrolyte for electrochemical performance of sodium‐ion batteries:A case study of hard carbon

在线全文

学校读者我要写书评

暂无评论

Carbon Energy 2024年第8期6卷 285-297页

作者： Jiabao Li Jingjing Hao Quan Yuan Ruoxing Wang Frederick Marlton Tianyi Wang chengyin Wang Xin Guo Guoxiu Wang College of Chemistry and Chemical Engineering Yangzhou UniversityYangzhouJiangsuChina School of Mathematical and Physical Sciences Centre for Clean Energy TechnologyFaculty of ScienceUniversity of Technology SydneySydneyAustralia

Compared with the extensively used ester‐based electrolyte,the hard carbon(HC)electrode is more compatible with the ether‐based counterpart in sodium‐ion batteries,which can lead to improved cycling stability and robust rate ***,the impact of salt anion on the electrochemical performance of HC electrodes has yet to be fully *** this study,the anionic chemistry in regulating the stability of electrolytes and the performance of sodium‐ion batteries have been systematically *** work shows discrepancies in the reductive stability of the anionic group,redox kinetics,and component/structure of solid electrolyte interface(SEI)with different salts(NaBF_(4),NaPF_(6),and NaSO_(3)CF_(3))in the typical ether solvent(diglyme).Particularly,the density functional theory calculation manifests the preferred decomposition of PF_(6)−due to the reduced reductive stability of anions in the solvation structure,thus leading to the formation of NaF‐rich *** investigation on redox kinetics reveals that the NaPF_(6)/diglyme can induce the fast ionic diffusion dynamic and low charge transfer barrier for HC electrode,thus resulting in superior sodium storage performance in terms of rate capability and cycling life,which outperforms those of NaBF_(4)/diglyme and NaSO_(3)CF_(3)/***,this work offers valuable insights for optimizing the electrochemical behaviors of electrode materials by regulating the anionic group in the electrolyte.

关键词： ether‐based electrolyte reaction kinetics salt anion SEI components sodium storage

Interfacial built-in electric field and crosslinking pathways enabling WS_(2)/Ti_(3)C_(2)T_(x) heterojunction with robust sodium storage at low temperature

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第2期89卷 635-645,I0014页

作者： Jiabao Li Shaocong Tang Jingjing Hao Quan Yuan Tianyi Wang Likun Pan Jinliang Li Shenbo Yang chengyin Wang College of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002JiangsuChina Shanghai Key Laboratory of Magnetic Resonance School of Physics and Electronic Science East China Normal UniversityShanghai 200241China Siyuan Laboratory Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy MaterialsGuangdong Provincial Key Laboratory of Nanophotonic ManipulationDepartment of PhysicsJinan UniversityGuangzhou 510632GuangdongChina Hongzhiwei Technology(Shanghai)CO.LTD Shanghai 200241China

Developing efficient energy storage for sodium-ion batteries(SIBs)by creating high-performance heterojunctions and understanding their interfacial interaction at the atomic/molecular level holds promise but is also ***,sluggish reaction kinetics at low temperatures restrict the operation of SIBs in cold ***,cross-linking nanoarchitectonics of WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,featuring built-in electric field(BIEF),have been developed,employing as a model to reveal the positive effect of heterojunction design and BIEF for modifying the reaction kinetics and electrochemical ***,the theoretical analysis manifests the discrepancy in work functions leads to the electronic flow from the electron-rich Ti_(3)C_(2)T_(x) to layered WS_(2),spontaneously forming the BIEF and“ion reservoir”at the heterogeneous ***,the generation of cross-linking pathways further promotes the transportation of electrons/ions,which guarantees rapid diffusion kinetics and excellent structure ***,superior sodium storage performance is obtained for the WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,with only 0.2%decay per cycle at 5.0 A g^(-1)(25℃)up to 1000 cycles and a high capacity of 293.5 mA h g^(-1)(0.1A g^(-1)after 100 cycles)even at-20℃.Importantly,the spontaneously formed BIEF,accompanied by“ion reservoir”,in heterojunction provides deep understandings of the correlation between structure fabricated and performance obtained.

关键词： WS_(2)/Ti_(3)C_(2)T_(x)heterojunction Built-in electric field Ion reservoir Reaction kinetics Sodium storage performance at low temperature

在线全文

学校读者我要写书评

暂无评论

除险加固水闸的消能防冲措施

水利水电科技进展 2017年第4期37卷 42-46,62页

作者：韩成银刘红军傅宗甫崔贞江苏省洪泽湖大堤高良涧闸加固工程建设处江苏淮安223199 河海大学水利水电学院江苏南京210098

基于某除险加固工程水力学模型试验,通过对闸下水流流态、流速分布、特征断面垂向最大平均流速以及冲刷特性的观测,分析了设计方案条件闸下水流流态恶化及冲刷严重的原因,即下游翼墙加固改变了水流的边界条件,导致出闸水流受到边界挤压... 详细信息

基于某除险加固工程水力学模型试验,通过对闸下水流流态、流速分布、特征断面垂向最大平均流速以及冲刷特性的观测,分析了设计方案条件闸下水流流态恶化及冲刷严重的原因,即下游翼墙加固改变了水流的边界条件,导致出闸水流受到边界挤压而主流集中,局部流速增大,冲刷加剧。通过不同消能防冲方案的试验比较,提出了利用分隔墩消除出闸水流集中的现象;分隔墩消除了主流受边界挤压现象,起到了改善闸下水流流态,均化闸下水流流速分布,降低河床最大流速,减轻闸下冲刷的作用,且体型结构简单,易于施工。

关键词：除险加固水闸消能防冲分隔墩

Physicochemical principles of hydrogen metallurgy in blast furnace

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第1期31卷 46-63页

作者： han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China

Based on the stoichiometric method and the free energy minimization method,an ideal model for the reduction of iron oxides by carbon and hydrogen under blast furnace conditions was established,and the reduction efficiency and theoretical energy consumption of the all-carbon blast furnace and the hydrogen-rich blast furnace were *** results show that after the reduction reaction is completed at the bottom of the blast furnace,the gas produced by reduction at 1600℃still has a certain excessive reduction capacity,which is due to the hydrogen brought in by the hydrogen-rich blast as well as the excess carbon monoxide generated by the reaction of the coke and the oxygen brought in by the *** the process of the gas with excessive reduction capacity rising from the bottom of the blast furnace and gas reduction process,the excessive reduction capacity of the gas gradually decreases with the increase in the dydrogen content in the *** the all-carbon blast furnace,the excess gas reduction capacity is the strongest,and the total energy consumption per ton of iron reduction is the *** shows that,for the current operation mode of the blast furnace,adding hydrogen in the blast furnace cannot reduce the consumption of carbon required for reduction per ton of iron,but rather increases the consumption of carbon.

关键词： Hydrogen metallurgy Excess gas reduction capacity Theoretical energy consumption Hydrogen-rich blast furnace Thermodynamic model Gibbs minimum free energy method

Engineered plant extracellular vesicles for autoimmune diseases therapy

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 2857-2873页

作者： Ruina han Yan Wu Yafei han Xiangfei Liu han Liu Jiacan Su Institute of Translational Medicine Shanghai UniversityShanghai 200444China Organoid Research Center Shanghai UniversityShanghai 200444China National Center for Translational Medicine(Shanghai)SHU Branch Shanghai UniversityShanghai 200444China Department of Orthopedics Shanghai Zhongye HospitalShanghai 200941China Department of Orthopedics Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200092China

Autoimmune diseases(AID)encompass a diverse array of conditions characterized by immune system dysregulation,resulting in aberrant responses of B cells and T cells against the body’s own healthy *** extracellular vesicles(PEVs)are nanoscale particles enclosed by phospholipid bilayers,secreted by plant cells,which facilitate intercellular communication by transporting various bioactive *** to their nanoscale structure,safety,abundant sources,low immunogenicity,high yield,biocompatibility,and effective targeting of the colon and liver,PEVs are regarded as a promising platform for the treatment of *** review provides a comprehensive summary of PEV biogenesis,physicochemical and biological properties,internalization mechanisms,isolation methods,and their applications in various diseases,with a specific focus on their potential roles in ***,we propose engineering approaches and administration methods for ***,we present an overview of the advantages and challenges associated with utilizing PEVs for the treatment of *** gaining a comprehensive understanding of PEVs,we anticipate the development of innovative therapeutic strategies for *** and engineered PEVs hold substantial promise as a valuable resource for innovative technologies in AID treatment.

关键词： autoimmune diseases plant extracellular vesicles extracellular vesicles engineering modification

Random Raman Fiber Laser as a Liquid Refractive Index Sensor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonic Sensors 2024年第1期14卷 13-22页

作者： Bing han Yuxi MA han WU Yong ZHAO College of Information Science and Engineering Northeastern UniversityShenyang 110819China Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology Qinhuangdao 066004China College of Electronics and Information Engineering Sichuan UniversityChengdu 610064China

In this paper,a new concept of forward-pumped random Raman fiber laser(RRFL)-based liquid refractive index sensing is proposed for the first *** liquid refractive index sensing,the flat fiber end immersed in the liquid can act as the point reflector for generating random fiber lasing and also as the sensing *** to the high sensitivity of the output power of the RRFL to the reflectivity provided by the point reflector in the ultralow reflectivity regime,the proposed RRFL is capable of achieving liquid refractive index sensing by measuring the random lasing output *** theoretically investigate the effects of the operating pump power and fiber length on the refractive index sensitivity for the proposed *** a proof-of-concept demonstration,we experimentally realize high-sensitivity half-open short-cavity RRFL-based liquid refractive index sensing with the maximum sensitivity and the sensing resolution of-39.88W/RIU and 2.5075×10^(-5) RIU,*** also experimentally verify that the refractive index sensitivity can be enhanced with the shorter fiber length of the *** work extends the application of the random fiber laser as a new platform for highly-sensitive refractive index sensing in chemical,biomedical,and environmental monitoring applications,etc.

关键词： Fiber optic sensors refractive index measurements fiber lasers Rayleigh scattering stimulated Raman scattering

FAST unveils a new era in the discovery of long-period pulsars in globular clusters

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(Physics,Mechanics & Astronomy) 2024年第6期67卷 185-186页

作者： Zhanwen han International Centre of Supernovae Yunnan Key LaboratoryYunnan ObservatoriesChinese Academy of SciencesKunming 650011China

Globular clusters(GC)are among the oldest celestial bodies in the Milky *** possessing millions of stars and have been going through abundant stellar interactions,GCs are futile ground for hunting for compact objects,particularly,neutron stars.A significant number of fast-spinning millisecond pulsars(MSPs)have been discovered,comprising the majority of known GC pulsars.

关键词： stars pulsars abundant