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Revealing excited states of rotational Bose-Einstein condensates

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The Innovation 2024年第1期5卷 41-48页

作者： Jianyuan Yin zhen Huang Yongyong Cai qiang Du Lei Zhang School of Mathematical Sciences Laboratory of Mathematics and Applied MathematicsPeking UniversityBeijing 100871China Department of Mathematics National University of SingaporeSingapore 119076Singapore Department of Mathematics University of CaliforniaBerkeleyBerkeleyCA 94720USA School of Mathematical Sciences Beijing Normal UniversityBeijing 100875China Department of Applied Physics and Applied Mathematics and Data Science Institute Columbia UniversityNew YorkNY 10027USA Beijing International Center for Mathematical Research Center for Quantitative BiologyCenter for Machine Learning ResearchPeking UniversityBeijing 100871China

Rotational Bose-Einstein condensates can exhibit quantized vortices as topological excitations.In this study,the ground and excited states of the rotational Bose-Einstein condensates are systematically studied by calculating the stationary points of the Gross-Pitaevskii energy functional.Various excited states and their connections at different rotational frequencies are revealed in solution landscapes constructed with the constrained high-index saddle dynamics method.Four excitation mechanisms are identified:vortex addition,rearrangement,merging,and splitting.We demonstrate changes in the ground state with increasing rotational frequencies and decipher the evolution of the stability of ground states.

关键词： method rotational excited

Molecular Chaperone-Dependent Polymer Translocation through Nanopores: The Effects of Chaperone Concentration and Chaperone-Polymer Interaction

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Chinese Journal of Polymer Science 2024年第1期42卷 125-132,I0011页

作者： Chang-Sheng Zuo Kang Wang Li-zhen sun Ting-Ting sun Department of Physics Zhejiang University of Science and TechnologyHangzhou 310023China Department of Applied Physics Zhejiang University of TechnologyHangzhou 310014China

The polymer translocation through a nanopore from a donor space(or named cis side) to a receiver space(trans side) in the chaperone-induced crowded environment has attracted increasing attention in recent years due to its significance in biological systems and technological applications. In this work, we mainly focus on the effects of chaperone concentration and chaperone-polymer interaction on the polymer translocation. By assuming the polymer translocation to be a quasi-equilibrium process, the free energy F of the polymer can be estimated by Rosenbluth-Rosenbluth method and then the translocation time τ can be calculated by Fokker-Plank equation based on the obtained free energy landscape. Our calculation results show that the translocation time can be controlled by independently tuning the chaperone concentration and chaperone-polymer interaction at the cis side or the trans side. There exists a critical chaperone-polymer attraction ε~*=-0.2 at which the volume exclusion and interaction effects of the chaperone can balance each other. Additionally, we also find that at large chaperone-polymer attraction, the translocation time is mainly governed by the diffusion coefficient of the polymer.

关键词： Polymer translocation Rosenbluth-Rosenbluth method Fokker-Plank equation Free energy landscapes

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Management of triplet excitons transition:fine regulation of Förster and dexter energy transfer simultaneously

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Light(Science & Applications) 2024年第2期13卷 302-315页

作者： Jiaqiang Wang Yujie Yang Xinnan sun Xiaoning Li Liyao Zhang zhen Li Institute of Molecular Aggregation Science Tianjin UniversityTianjin300072China School of Life Sciences Tianjin UniversityTianjin300072China Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Department of ChemistryWuhan UniversityWuhan430072China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan430072China Joint School of National University of Singapore Tianjin UniversityInternational Campus of Tianjin UniversityBinhai New CityFuzhou350207China

Understanding and management of triplet excitons transition in the same molecule remain a great challenge.Hence,for the first time,by host engineering,manageable transitions of triplet excitons in a naphthalimide derivative NDOH were achieved,and monitored through the intensity ratio(ITADF/IRTP)between thermally activated delayed fluorescence(TADF)and room-temperature phosphorescence(RTP).Energy differences between lowest triplet excited states of host and guest were changed from 0.03 to 0.17 eV,and ITADF/IRTP of NDOH decreased by 200 times,thus red shifting the afterglow color.It was proposed that shorter conjugation length led to larger band gaps of host materials,thus contributing to efficient Dexter and inefficient Förster energy transfer.Interestingly,no transition to singlet state and only strongest RTP with quantum yield of 13.9%could be observed,when PBNC with loosest stacking and largest band gap acted as host.This work provides novel insight for the management and prediction of triplet exciton transitions and the development of smart afterglow materials.

关键词： materials transition transitions

A Wideband High-Gain Sawtooth Slot Array Antenna with Frequency-Scanning at Lower Frequency and Fixed-Beam at Higher Frequency

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Chinese Journal of Electronics 2024年第2期33卷 463-471页

作者： qiang sun Yongling BAN Jun HU School of Electronic Science and Engineering University of Electronic Science and Technology of China

Exploring the multifunctional array antenna suitable for complex communication environment has very important research value. In this paper, a millimeter wave(mm-wave) double longitudinal sawtooth slot array antenna(DLSA) based on substrate integrated waveguide(SIW) technology is proposed, which has wideband, highgain and novel beam characteristics. Two irregular longitudinal slots are etched on the SIW conductor surface as the radiation structure. To improve the bandwidth of the DLSA, the metallized vias are added at the transition point of the slots to construct multiple resonant frequency points. By adjusting the size of the slots and the position of the metallized vias, the phase constant can be regulated, and the unusual beam characteristics can be obtained. That is to say, in the lower frequency band, the beam pointing angle increases with frequency. In the higher frequency band,the beam pointing angle is maintained at a fixed angle. Finally, to improve the antenna gain, a 16 × 8 DLSA is fabricated, measured and discussed. The proposed antenna has an impedance matching bandwidth close to 9.7 GHz.From 27 to 33 GHz, the beam pointing angle changes from 8° to 29°. From 33 to 37 GHz, the beam pointing angle is fixed at 29°, and the pointing angle error range is ±1°. In addition, the measured maximum gain is 22.9 d Bi at32 GHz.

关键词： Frequency-scanning Fixed beam High-gain Millimeter-wave Sawtooth slot Wideband

Laser manufacturing of spatial resolution approaching quantum limit

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Light(Science & Applications) 2024年第3期13卷 421-428页

作者： Xiao-Jie Wang Hong-Hua Fang zhen-Ze Li Dan Wang Hong-Bo sun State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun 130012China

Atomic and close-to-atom scale manufacturing is a promising avenue toward single-photon emitters,single-electron transistors,single-atom memory,and quantum-bit devices for future communication,computation,and sensing applications.Laser manufacturing is outstanding to this end for ease of beam manipulation,batch production,and no requirement for photomasks.It is,however,suffering from optical diffraction limits.Herein,we report a spatial resolution improved to the quantum limit by exploiting a threshold tracing and lock-in method,whereby the two-order gap between atomic point defect complexes and optical diffraction limit is surpassed,and a feature size of<5 nm is realized.The underlying physics is that the uncertainty of local atom thermal motion dominates electron excitation,rather than the power density slope of the incident laser.We show that the colour centre yield in hexagonal boron nitride is transformed from stochastic to deterministic,and the emission from individual sites becomes polychromatic to monochromatic.As a result,single colour centres in the regular array are deterministically created with a unity yield and high positional accuracy,serving as a step forward for integrated quantum technological applications.

关键词： quantum limit resolution

Analysis of pressure response at an observation well against pressure build-up by early stage of CO_(2)geological storage project

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 470-482页

作者： qiang sun Kyuro Sasaki Qinxi Dong zhenni Ye Hui Wang Huan sun School of Civil Engineering and Architecture Hainan UniversityHaikou570228China Faculty of Engineering Kyushu University744 MotookaNishi-kuFukuoka819-0385Japan Key Laboratory of Equipment Safety and Intelligent Technology for Guangzhou Rail Transit System Guangzhou510430China

To ensure a safe and stable CO_(2)storage,pressure responses at an observation well are expected to be an important and useful field monitoring item to estimate the CO_(2)storage behaviors and the aquifer parameters during and after injecting CO_(2),because it can detect whether the injected CO_(2)leaks to the ground surface or the bottom of the sea.In this study,pressure responses were simulated to present design factors such as well location and pressure transmitter of the observation well.Numerical simulations on the pressure response and the time-delay from pressure build-up after CO_(2)injection were conducted by considering aquifer parameters and distance from the CO_(2)injection well to an observation well.The measurement resolution of a pressure transmitter installed in the observation well was presented based on numerical simulation results of the pressure response against pressure build-up at the injection well and CO_(2)plume front propagations.Furthermore,the pressure response at an observation well was estimated by comparing the numerical simulation results with the curve of CO_(2)saturation and relative permeability.It was also suggested that the analytical solution can be used for the analysis of the pressure response tendency using pressure build-up and dimensionless parameters of hydraulic diffusivity.Thus,a criterion was established for selecting a pressure transducer installed at an observation well to monitor the pressure responses with sufficient accuracy and resolution,considering the distance from the injection well and the pressure build-up at the injection well,for future carbon capture and storage(CCS)projects.

关键词： CO_(2)storage Saline aquifer Observation well Pressure response CO_(2)saturation

Ferroptosis mechanism and Alzheimer's disease

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Neural Regeneration Research 2024年第8期19卷 1741-1750页

作者： Lina Feng Jingyi sun Ling Xia qiang Shi Yajun Hou Lili Zhang Mingquan Li Cundong Fan Baoliang sun Shandong Key Laboratory of TCM Multi-Target Intervention and Disease Control the Second Affiliated Hospital of Shandong First Medical UniversityTaianShandong ProvinceChina Department of Internal Medicine Taian Traffic HospitalTaianShandong ProvinceChina Department of Neurology the Third Affiliated Clinical Hospital of Changchun University of Chinese MedicineChangchunJilin ProvinceChina

Regulated cell death is a genetically determined form of programmed cell death that commonly occurs during the development of living organisms.This process plays a crucial role in modulating homeostasis and is evolutionarily conserved across a diverse range of living organisms.Ferroptosis is a classic regulatory mode of cell death.Extensive studies of regulatory cell death in Alzheimer’s disease have yielded increasing evidence that fe rroptosis is closely related to the occurrence,development,and prognosis of Alzheimer’s disease.This review summarizes the molecular mechanisms of ferroptosis and recent research advances in the role of ferro ptosis in Alzheimer’s disease.Our findings are expected to serve as a theoretical and experimental foundation for clinical research and targeted therapy for Alzheimer’s disease.

关键词： Alzheimer’s disease apolipoprotein E Fe^(2+) ferroptosis glial cell glutathione peroxidase 4 imbalance in iron homeostasis lipid peroxidation regulated cell death system Xc^(-)

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Hydrometallurgical recovery of lithium carbonate and iron phosphate from blended cathode materials of spent lithium-ion battery

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Rare Metals 2024年第3期43卷 1275-1287页

作者： Shao-Le Song Run-Qing Liu Miao-Miao sun Ai-Gang zhen Fan-zhen Kong Yue Yang School of Minerals Processing and Bioengineering Central South UniversityChangsha410083China Zhejiang Tianneng New Materials Co. Ltd.Huzhou313103China

The recycling of cathode materials from spent lithium-ion battery has attracted extensive attention,but few research have focused on spent blended cathode materials.In reality,the blended materials of lithium iron phosphate and ternary are widely used in electric vehicles,so it is critical to design an effective recycling technique.In this study,an efficient method for recovering Li and Fe from the blended cathode materials of spent LiFePO_(4)and LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)batteries is proposed.First,87%A1 was removed by alkali leaching.Then,91.65%Li,72.08%Ni,64.6%Co and 71.66%Mn were further separated by selective leaching with H_(2)SO_(4)and H_(2)O_(2).Li,Ni,Co and Mn in solution were recovered in the form of Li_(2)CO_(3)and hydroxide respectively.Subsequently,98.38%Fe was leached from the residue by two stage process,and it is recovered as FePO_(4)·2H_(2)O with a purity of 99.5%by precipitation.Fe and P were present in FePO_(4)·2H_(2)O in amounts of 28.34%and 15.98%,respectively.Additionally,the drift and control of various components were discussed,and cost-benefit analysis was used to assess the feasibility of potential application.

关键词： Spent lithium-ion battery Blended cathode materials Recovery Lithium carbonate Iron phosphate

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Core competencies and perceived training needs of nurses in the background of Internet plus nursing service:a qualitative descriptive study

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Frontiers of Nursing 2024年第2期11卷 181-190页

作者： qiang-Hui-Zi Zhang Wei-Wei Liu zhen-zhen Cheng School of Nursing Capital Medical UniversityBeijing 100069China Department of Orthopedics Peking University Shougang HospitalBeijing 100043China

Background:The Internet plus nursing service program is being piloted in China,which has become a new home nursing service model led by nurses.To enable safe and effective homecare service delivery,nurses working in the program need a high level of competency.However,the content of these core competencies and the training needs of nurses for Internet plus nursing services are still unknown.Aim:To describe nurses’perceptions of core competencies and training needs to work in the Internet plus nursing service program,thereby providing a reference for the development of training programs.Methods:A qualitative descriptive study using semi-structured interviews was conducted on 15 nurses with experience of working in the Internet plus nursing service program.Interviews were audio-recorded and transcribed verbatim,and the data were analyzed using thematic analysis.Results:Core competencies involved comprehensive assessment competence,direct care practice competence,health education and consulting competence,risk estimation and response competence,and communication competence.Training needs involved complex operational items,knowledge of chronic disease management,professional communication,risk identification and response,nursing standards,norms,and procedures,and utilization of information technology.Conclusions:The training system may be developed based on nurses’core competencies and their training needs to promote professional development of the Internet plus nursing service.

关键词： core competence Internet plus nursing service nursing qualitative study training needs

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