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Strong Solutions of an Incompressible Phase-field Model with Variable Density

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Acta Mathematicae Applicatae Sinica 2024年

作者： Ying-hua LI Yong WANG han-bin cai School of Mathematical Sciences South China Normal University

We study the initial-boundary value problem of an incompressible Navier-Stokes-Cahn-Hilliard system with variable density. We prove the existence and uniqueness of the local strong solution in two or three dimensions. Moreover, we establish a two-dimensional blow-up criterion in terms of the temporal integral of the square of maximum norm of velocity.

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PHiFA—A tool for numerical propagation of high-fidelity astrodynamics

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Astrodynamics 2022年第2期6卷 189-204页

作者： Yang Yang Erik Klein Changyong He han cai Yan Zhang School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518000China TU Braunschweig Institut for Space Systems38108 BraunschweigGermany ENSG-Géomatics Institut national de l’information géographique et forestière(IGN)F-77455 Marne-la-ValléeFrance School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

This paper presents a tool for the numerical propagation of high-fidelity astrodynamics,called PHiFA.The coupled orbit–attitude dynamics for space objects are modeled by considering various types of perturbative forces and torques.Two methods have been implemented to calculate the surface forces:the area matrix method and the beam method.The beam method is more precise as it discretizes the source media(e.g.,sunlight and aerodynamic wind)and the surface of the target into multiple rays and finite elements,respectively,and then accumulates the effect of each hit.The PHiFA tool was tested and validated using a 3U CubeSat model and the defunct European environment satellite(Envisat)model.

关键词： coupled orbit-attitude dynamics surface force modeling beam method European environment satellite (Envisat)

Topological phases of quantized light

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National Science Review 2021年第1期8卷 69-80页

作者： han cai Da-Wei Wang Interdisciplinary Center for Quantum Information and State Key Laboratory of Modern Optical Instrumentation Zhejiang Province Key Laboratory of Quantum Technology and Device and Department of Physics Zhejiang University CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences

Topological photonics is an emerging research area that focuses on the topological states of classical light.Here we reveal the topological phases that are intrinsic to the quantum nature of light, i.e. solely related to the quantized Fock states and the inhomogeneous coupling strengths between them. The Hamiltonian of two cavities coupled with a two-level atom is an intrinsic one-dimensional Su-Schriefer-Heeger model of Fock states. By adding another cavity, the Fock-state lattice is extended to two dimensions with a honeycomb structure, where the strain due to the inhomogeneous coupling strengths of the annihilation operator induces a Lifshitz topological phase transition between a semimetal and three band insulators within the lattice. In the semimetallic phase, the strain is equivalent to a pseudomagnetic field, which results in the quantization of the Landau levels and the valley Hall effect. We further construct an inhomogeneous Fock-state Haldane model where the topological phases can be characterized by the topological markers.With d cavities being coupled to the atom, the lattice is extended to d-1 dimensions without an upper limit. In this study we demonstrate a fundamental distinction between the topological phases in quantum and classical optics and provide a novel platform for studying topological physics in dimensions higher than three.

关键词： topological phases Su-Schriefer-Heeger model Jaynes-Cummings model strain-induced magnetic field Haldane model

Crucial role of iron plaque on thallium uptake by rice plant

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Waste Disposal and Sustainable Energy 2023年第1期5卷 89-96页

作者： Xiaoyin Zhang Wenhuan Yuan Juan Liu Haoran Li han cai Haiyao Hu Dongyi Ren Yuhua Zhang Yuxiang Shen Jin Wang School of Environmental Science and Engineering and Key Laboratory of Waters Quality&Conservation in the Pearl River Delta Ministry of EducationGuangzhou UniversityGuangzhou510006China Guangdong Provincial Key Laboratory of Radionuclides Pollution Control and Resources Guangzhou510006China

Iron plaque is a Fe-containing oxide film produced by the oxidation of Fe(II)in the rice root system under the combined action of oxygen infiltration and other microorganisms.Owing to its special surface structure and physio-chemical properties,the iron plaque has a strong absorption capacity for a variety of heavy metal ions.This study aimed to first investigate the effects of Fe species on the geochemical fractionation of Tl in typical paddy soil systems affected by industrial activities,followed by pot culture experiments to probe the effects of Fe species on the uptake and translocation of Tl in rice plants.The results of field work preliminarily showed that iron at different valences affected the conversion of the Tl geochemical fraction in the soil.Oxidizable Tl exerted significant positive correlation relationships with Fe2+and negative correlation relationships with Fe3+,while reducible Tl only displayed a positive correlation with Fe3+.Further analysis by pot culture experiments revealed that the contents of Fe were significantly positively correlated with Tl contents in Fe plaque(R2=0.529).In contrast,the water-soluble Tl contents in the soil were significantly negatively correlated with the contents of Fe(R2=–0.90,phan that in the above-ground tissues,which indicates that most Fe plaque exerts a certain degree of inhibition on Tl migration into the above-ground tissues of rice plants.All these findings indicate that Fe film is also an important carrier of Tl transfer in the soil–rice plant system,which provides new scientific support for the remediation of typical Tl-contaminated rice fields.

关键词： Iron oxide Thallium pollution Iron plaque Rice

Promoted intramolecular photoinduced-electron transfer for multi-mode imaging-guided cancer photothermal therapy

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Rare Metals 2022年第1期41卷 56-66页

作者： Xin-Yu Qu Ying Hong han cai Xu Sun Qing Shen Dong-Liang Yang Xiao-Chen Dong Ai-Hong Jiao Peng Chen Jin-Jun Shao Key Laboratory of Flexible Electronics and Institute of Advanced Materials Nanjing Tech UniversityNanjing 211800China Nanjing University of Information Science and Technology Nanjing 210044China Yuhuangding Hospital of Qingdao University Yantai 264000China School of Chemical and Biomedical Engineering Nanyang Technological UniversitySingapore 637459Singapore

To develop smart and efficient near-infrared(NIR)organic dyes for photothermal cancer therapy is of great challenge.Herein,a pH-sensitive NIR dye BTN with donor–acceptor–donor scaffold has been synthesized.Two periphery electron-donating dimethylamine groups in BTN can not only promote the intramolecular photoinduced electron transfer(PET),but also bind protons to transform into electron-deficient ammonium cation for enhanced intramolecular charge transfer(ICT)under acidic circumstance.Through enveloping with amphiphilic polymeric 1,2-distearoyl-ras-glycerol-3-phosphatidyl ethanolamine-N-polyethyleneglycol-2000(DSPE-mPEG2000),BTN nanoparticles(NPs)were fabricated with robust NIR absorption covering 600–900 nm,excellent photothermal conversion efficiency(43.2%),and good photostability.Additionally,BTN NPs can selectively target lysosomes.Through tailing intravenous injection into tumor-bearing nude mice,BTN NPs demonstrate outstanding photoacoustic/photothermal/fluorescence imaging-guided photothermal therapy for tumor ablation.

关键词： Photothermal Phototherapy Near-infrared dye Photoinduced-electron transfer Intramolecular charge transfer

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The soybean GmPUB21-interacting protein GmDi19-5 responds to drought and salinity stresses via an ABA-dependent pathway

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The Crop Journal 2023年第4期11卷 1152-1162页

作者： Yunhua Yang Rui Ren Adhimoolam Karthikeyan Jinlong Yin Tongtong Jin Fei Fang han cai Mengzhuo Liu Dagang Wang Haijian Zhi Kai Li National Center for Soybean Improvement National Key Laboratory for Crop Genetics and Germplasm EnhancementKey Laboratory of Biology and Genetic Improvement of Soybean Ministry of AgricultureNanjing Agricultural UniversityNanjing 210095JiangsuChina College of Agronomy&Center for Crop Genome Engineering Henan Agricultural UniversityZhengzhou 450046HenanChina Subtropical Horticulture Research Institute Jeju National UniversityJeju 63243Republic of Korea

Drought-induced protein 19(Di19) is a Cys2/His2 zinc-finger protein that functions in plant growth and development and in tolerance to abiotic stresses.Gm PUB21,an E3 ubiquitin ligase,negatively regulates drought and salinity response in soybean.We identified potential interaction target proteins of Gm PUB21by yeast two-hybrid c DNA library screening,Gm Di19-5 as a candidate.Bimolecular fluorescence complementation and glutathionine-S-transferase pull-down assays confirmed the interaction between Gm Di19-5 and Gm PUB21.Gm Di19-5 was induced by Na Cl,drought,and abscisic acid(ABA) treatments.Gm Di19-5 was expressed in the cytoplasm and nucleus.Gm Di19-5 overexpression conferred hypersensitivity to drought and high salinity,whereas Gm Di19-5 silencing increased drought and salinity tolerance.Transcripts of ABA-and stress response-associated genes including Gm RAB18 and Gm DREB2A were downregulated in Gm Di19-5-overexpressing plants under drought and salinity stresses.ABA decreased the protein level of Gm Di19-5 in vivo,whereas Gm PUB21 increased the decrease of Gm Di19-5 after exogenous ABA application.The accumulation of Gm PUB21 was also inhibited by Gm Di19-5.We conclude that Gm PUB21 and Gm Di19-5 collaborate to regulate drought and salinity tolerance via an ABA-dependent pathway.

关键词： Soybean Drought and salinity stresses GmDi19-5 GmPUB21 ABA-dependent pathway

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LEO Mega Constellations:Review of Development,Impact,Surveillance,and Governance

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Space(Science & Technology) 2022年第1期2022卷 472-488页

作者： Jingrui Zhang Yifan cai Chenbao Xue Zhirun Xue han cai School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

The rapid development of Low Earth Orbit(LEO)mega constellations has significantly contributed to several aspects of human scientific progress,such as communication,navigation,and remote sensing.However,unrestrained deployment of constellations has also strained orbital resources and increased spacecraft congestion in LEO,which seriously affects the safety of in-orbit operations of many space assets.For the long-term and sustainable development of space activities in LEO regions,space environment stability must be maintained using more rational surveillance and governance mechanisms.This review contributes to the research gap and facilitates the development of LEO mega constellations.First,the current development of typical LEO mega constellations is reviewed,followed by the analysis of the impact of LEO mega constellations in terms of astronomical observation,spacecraft safety in orbit,and space environment evolution.Then,two main solutions to conduct the challenges raised by LEO mage constellations are elaborated:one is to ensure the safety operation of spacecraft using space surveillance infrastructures and space situational awareness technologies,and the other is to accelerate the deorbit of constellation satellites at the end of life based on postmission disposal and active removal methods.Finally,the future development and potential research directions of LEO mega constellations are prospected.

关键词： Impact restrained maintained

盐胁迫下外源褪黑素和丛枝菌根真菌对月季幼苗生长生理特性的影响

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西北植物学报 2024年第3期44卷 370-380页

作者：周英谢科蔡汉黄长兵苏州农业职业技术学院江苏苏州215008 南京航空航天大学南京450003 扬州大学园艺学院江苏扬州321000

【目的】盐胁迫易导致月季生长发育不良、观赏品质下降,严重影响其在高盐环境或沿海地区室外绿化应用,探究施用外源褪黑素(MT)和接种丛枝菌根真菌(AMF)对其幼苗生长、叶绿素荧光参数以及激素代谢的调控作用,解析它们促进月季适应盐胁迫... 详细信息

【目的】盐胁迫易导致月季生长发育不良、观赏品质下降,严重影响其在高盐环境或沿海地区室外绿化应用,探究施用外源褪黑素(MT)和接种丛枝菌根真菌(AMF)对其幼苗生长、叶绿素荧光参数以及激素代谢的调控作用,解析它们促进月季适应盐胁迫的生理生化机制,对于增强月季抗盐性,扩大月季应用范围具有重要意义。【方法】以月季品种‘月月红’幼苗为试验材料,采用室内盆栽试验,设置对照(CK)、100 mol/L NaCl胁迫、根际施用MT、根际接种AMF幼套近明球囊霉(Claroideoglomus etunicatum)及其组合等8个处理,考察各处理对月季幼苗生长、叶绿素荧光参数、激素代谢及抗氧化系统的影响。【结果】(1)施用MT可以促进AMF对月季幼苗根系的侵染,提高侵染率、丛枝着生率、泡囊数和侵入点数;(2)月季幼苗株高、茎粗以及生物量等在盐胁迫下显著下降,在MT或AMF处理下均不同程度增加,而AMF+MT处理下株高、茎粗无显著变化,地上部干重、地下部干重分别显著增加24.1%和37.0%;(3)月季幼苗叶绿素含量在盐胁迫下显著下降,叶绿素荧光参数也降低,MT或AMF处理能提高盐胁迫月季幼苗叶绿素含量以及叶绿素荧光参数,AMF+MT处理则使叶绿素总量、叶绿素a/b分别增加46.2%和67.2%,PSⅡ最大光化学效率(F_(v)/F_(m))、潜在活性(F_(v)/F_(o))、实际光化学效率(ΦPSⅡ)、有效光化学量子效率(Fv'/Fm')、光化学淬灭系数(qP)分别增加4.9%、51.0%、175.0%、168.7%和92.5%,而NPQ下降42.7%;(4)在盐胁迫下,月季叶片中玉米素(ZT)、赤霉素(GA)、生长素(IAA)含量下降,而脱落酸(ABA)含量增加,MT或AMF处理有利于盐胁迫下ZT、GA、IAA含量的提高以及ABA含量的下降,AMF+MT处理后ZT、GA、IAA分别增加146.9%、116.9%、35.7%,ABA下降21.1%;(5)在盐胁迫下,抗氧化酶SOD、CAT活性增强,超氧阴离子(O_(2)^(-·))产生速率和H_(2)O_(2)累积大量增加,MT或AMF处理有助于增加抗氧化酶活性并减少O_(2)^(-·)产生速率和H_(2)O_(2)含量,而AMF+MT处理能够进一步激活SOD、CAT活性,降低O_(2)^(-·)产生速率和H_(2)O_(2)累积。【结论】接种AMF、添加MT或者AMF+MT处理均可以提高盐胁迫下月季幼苗叶绿素含量,保护叶绿素荧光系统,维持植物内源激素的平衡,激活SOD、CAT等抗氧化酶活性以及降低脂质过氧化和H_(2)O_(2)累积,以减轻盐胁迫对月季幼苗的伤害,促进月季生长,并以AMF+MT处理增强月季幼苗抗盐性的效果更佳。

关键词：月季盐胁迫褪黑素丛枝菌根真菌(AMF) 生长叶绿素荧光参数激素代谢抗氧化酶

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Measuring Zak phase in room-temperature atoms

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Light(Science & Applications) 2022年第10期11卷 2530-2539页

作者： Ruosong Mao Xingqi Xu Jiefei Wang Chenran Xu Gewei Qian han cai Shi-Yao Zhu Da-Wei Wang Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical Instrumentationand Zhejiang Province Key Laboratory of Quantum Technology and DeviceSchool of PhysicsZhejiang UniversityHangzhou 310027China College of Optical Science and Engineering Zhejiang UniversityHangzhou 310027China Hefei National Laboratory Hefei 230088China CAS Center of Excellence in Topological Quantum Computation 100190 BeijingChina

Cold atoms provide a flexible platform for synthesizing and characterizing topological matter,where geometric phases play a central role.However,cold atoms are intrinsically prone to thermal noise,which can overwhelm the topological response and hamper promised applications.On the other hand,geometric phases also determine the energy spectra of particles subjected to a static force,based on the polarization relation between Wannier-Stark ladders and geometric Zak phases.By exploiting this relation,we develop a method to extract geometric phases from energy spectra of room-temperature superradiance lattices,which are momentum-space lattices of timed Dicke states.In such momentum-space lattices the thermal motion of atoms,instead of being a source of noise,provides effective forces which lead to spectroscopic signatures of the Zak phases.We measure Zak phases directly from the anti-crossings between Wannier-Stark ladders in the Doppler-broadened absorption spectra of superradiance lattices.Our approach paves the way of measuring topological invariants and developing their applications in room-temperature atoms.

关键词： topological momentum invariants