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First integrals of the axisymmetric shape equation of lipid membranes

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Chinese Physics B 2018年第3期27卷 551-559页

作者： Yi-Heng zhang Zachary McDargh zhan-chun tu Department of Physics Beijing Normal UniversityBeijing 100875China Department of Physics Carnegie Mellon University5000 Forbes AvenuePittsburgh PA 15213USA

The shape equation of lipid membranes is a fourth-order partial differential *** the axisymmetric condi-tion,this equation was transformed into a second-order ordinary differential equation(ODE)by Zheng and Liu(***.E 482856(1993)).Here we try to further reduce this second-order ODE to a first-order ***,we invert the usual process of variational calculus,that is,we construct a Lagrangian for which the ODE is the corresponding Euler-Lagrange ***,we seek symmetries of this Lagrangian according to the Noether *** a certain restriction on Lie groups of the shape equation,we find that the first integral only exists when the shape equation is identical to the Will-more equation,in which case the symmetry leading to the first integral is scale *** also obtain the mechanical interpretation of the first integral by using the membrane stress tensor.

关键词： lipid membrane shape equation first integral Noether theorem

A single-point measurement scheme for quantum work based on the squeezing state

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Communications in Theoretical Physics 2021年第6期73卷 51-58页

作者： Bao-Ming Xu Jian Zou zhan-chun tu Shandong Key Laboratory of Biophysics Institute of BiophysicsDezhou UniversityDezhou 253023China School of Physics Beijing Institute of TechnologyBeijing 100081China Department of Physics Beijing Normal UniversityBeijing 100875China

To investigate the role of initial quantum coherence in work-probability distribution,it is necessary to consider an incomplete or partial measurement,in which the energy cannot be fully discriminated by the *** this paper,we use a harmonic oscillator with a coherent or squeezing state to realize this incomplete or partial measurement,and propose a unified framework of quantum work statistics for a closed system with an arbitrary initial *** find that work is proportional to the change of the real part of the coherent state parameter,i.e.,quantum work can be estimated by the coherent state *** resulting work-probability distribution includes the initial quantum coherence,and can be reduced to the result of the traditional two projective energy measurement scheme(TPM)by squeezing the state of the harmonic *** measurement scheme reveals the fundamental connections between measurement error and coherent *** introducing a‘coherent work-to-noise ratio’,we find the optimal measurement error,which is determined by the energy difference between the superposed energy *** an application,we consider a driven two-level system and investigate the effects of driving velocity on work *** find that only when the driving velocity matches the transition frequency of the system can initial quantum coherence play an important role.

关键词： work distribution quantum coherence coherent state squeezing state

Recent advance on the efficiency at maximum power of heat engines

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Chinese Physics B 2012年第2期21卷 36-45页

作者： tu zhan-chun Department of Physics Beijing Normal UniversityBeijing 100875China

This review reports several key advances on the theoretical investigations of efficiency at maximum power of heat engines in the past five years. The analytical results of efficiency at maximum power for the Curzon-Ahlborn heat engine, the stochastic heat engine constructed from a Brownian particle, and Feynman＇s ratchet as a heat engine are presented. It is found that： the efficiency at maximum power exhibits universal behavior at small relative temperature differences; the lower and the upper bounds might exist under quite general conditions; and the problem of efficiency at maximum power comes down to seeking for the minimum irreversible entropy production in each finite-time isothermal process for a given time.

关键词： effciency at maximum power heat engine universality bounds

A Possible Generalized Form of Jarzynski Equality

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Communications in Theoretical Physics 2006年第5X期46卷 886-890页

作者： tu zhan-chun ZHOU Zi-Cong Department of Physics Tamkang University Tamsui 25137 Taiwan China Physics Division National Center for Theoretical Sciences at Taipei National Taiwan University Taipei 10617 Taiwan China

The crucial condition in the derivation of the Jarzynski equality （JE） from the fluctuation theorem is that the time integral of the phase space contraction factor can be exactly expressed as the entropy production resulting from the heat absorbed by the system from the thermal bath. For the system violating this condition, a more general form of JE may exist. This existence is verified by three Gedanken experiments and numerical simulations, and may be confirmed by the real experiment in the nanoscale.

关键词： Jarzynski equality fluctuation theorem entropy production

High-energy-density lithium manganese iron phosphate for lithium-ion batteries: Progresses, challenges, and prospects

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Journal of Energy Chemistry 2025年第1期100卷 1-17页

作者： Bokun zhang Xiaoyun Wang Shuai Wang Yan Li Libo Chen Handong Jiao Zhijing Yu Jiguo tu State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Research Institute for Intelligent Wearable Systems The Hong Kong Polytechnic University Institute of Advanced Structure Technology Beijing Institute of Technology

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate (LiMnxFe1-xPO4) has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** LiMnxFe1-xPO4has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMnxFe1-xPO4to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMnxFe1-xPO4,including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable LiMnxFe1-xPO4materials,to achieve practical energy storage requirements.

关键词： Lithium manganese iron phosphate High energy density Lithium-ion batteries Reaction mechanism Tap density

Increased excitatory amino acid transporter 2 levels in basolateral amygdala astrocytes mediate chronic stress–induced anxiety-like behavior

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Neural Regeneration Research 2025年第6期20卷 1721-1734页

作者： Xirong Xu Shoumin Xuan Shuai Chen Dan Liu Qian Xiao Jie tu Shenzhen Key Laboratory of Neuroimmunomodulation for Neurological Diseases Shenzhen-Hong Kong Institute of Brain ScienceShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina CAS Key Laboratory of Brain Connectome and Manipulation Brain Cognition and Brain Disease Institute(BCBDI)Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina Guangdong Provincial Key Laboratory of Brain Connectome and Behavior the Brain Cognition and Brain Disease Institute(BCBDI)Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina University of Chinese of Academy of Sciences BeijingChina Faculty of Life and Health Sciences Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina

The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain function and encoding behaviors associated with ***, astrocytes in the basolateral amygdala have been found to play a role in the modulation of anxiety-like behaviors triggered by chronic stress. Nevertheless, the precise molecular mechanisms by which basolateral amygdala astrocytes regulate chronic stress–induced anxiety-like behaviors remain to be fully elucidated. In this study, we found that in a mouse model of anxiety triggered by unpredictable chronic mild stress, the expression of excitatory amino acid transporter 2 was upregulated in the basolateral amygdala. Interestingly, our findings indicate that the targeted knockdown of excitatory amino acid transporter 2 specifically within the basolateral amygdala astrocytes was able to rescue the anxiety-like behavior in mice subjected to stress. Furthermore, we found that the overexpression of excitatory amino acid transporter 2 in the basolateral amygdala, whether achieved through intracranial administration of excitatory amino acid transporter 2agonists or through injection of excitatory amino acid transporter 2-overexpressing viruses with GfaABC1D promoters, evoked anxiety-like behavior in mice. Our single-nucleus RNA sequencing analysis further confirmed that chronic stress induced an upregulation of excitatory amino acid transporter 2 specifically in astrocytes in the basolateral amygdala. Moreover, through in vivo calcium signal recordings, we found that the frequency of calcium activity in the basolateral amygdala of mice subjected to chronic stress was higher compared with normal *** knocking down the expression of excitatory amino acid transporter 2 in the basolateral amygdala, the frequency of calcium activity was not significantly increased, and anxiety-like behavior was ob

关键词： anxiety astrocytes basolateral amygdala behavior dihydrokainic acid excitatory amino acid transporter 2 fiber photometry glutamate LDN-212320 transporter

Dioxyxanthones from Polygala hongkongensis and Their Cytotoxicity

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Chemical Research in Chinese Universities 2011年第5期27卷 777-779页

作者： WU Jian-feng tu Peng-fei zhan Hai-tao GAO Jing-chun College of Medicine Foshan University Foshan 528000 P. R. China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Health Science Center Beijing 100191 P. R. China Department of Biology and Chemistry City University of Hongkong Hong Kong SPR P. R. China

Two new dioxyxanthones, polyhongkongenoxanthones A and B（1 and 2） were isolated from the herbs of Polygala hongkongensis, together with six known xanthones. Their structures were elucidated on the basis of chemical and spectroscopic evidence. The isolates were tested for their cytotoxicity against three tumor cell lines（HepG2, GLC-82 and MCF-7, HepG2=human hepatocellular carcinoma cells; GLC-82=human lung carcinoma cells; MCF-7= human breast carcinoma cells） by MTT assay, among which polyhongkongenoxanthone B（2）, 1,7-dihydroxy-2,3- methylenedioxyxanthone（3） and 1,7-dihydroxy-3,4,8-trimethoxyxanthone（6） are potential antitumor candidate due to their significant cytotoxic effects on the three cell lines..

关键词： Polygala hongkongensis Polygalaceae Dioxyxanthone Polyhongkongenoxanthone A and B Cytotoxicity

Responses of greenhouse gas fluxes to experimental warming in wheat season under conventional tillage and no-tillage fields

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Journal of Environmental Sciences 2017年第4期29卷 314-327页

作者： chun tu Fadong Li Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences University of Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences

Understanding the effects of warming on greenhouse gas（GHG, such as N2O, CH4 and CO2 ）feedbacks to climate change represents the major environmental issue. However, little information is available on how warming effects on GHG fluxes in farmland of North China Plain（NCP）. An infrared warming simulation experiment was used to assess the responses of N2O, CH4 and CO2 to warming in wheat season of 2012–2014 from conventional tillage（CT） and no-tillage（NT） systems. The results showed that warming increased cumulative N2O emission by 7.7% in CT but decreased it by 9.7% in NT fields（p 〈 0.05）. Cumulative CH4 uptake and CO2 emission were increased by 28.7%–51.7% and 6.3%–15.9% in both two tillage systems,respectively（p 〈 0.05）. The stepwise regressions relationship between GHG fluxes and soil temperature and soil moisture indicated that the supply soil moisture due to irrigation and precipitation would enhance the positive warming effects on GHG fluxes in two wheat ***, in 2013, the long-term drought stress due to infrared warming and less precipitation decreased N2O and CO2 emission in warmed treatments. In contrast, warming during this time increased CH4 emission from deep soil depth. Across two years wheat seasons, warming significantly decreased by 30.3% and 63.9% sustained-flux global warming potential（SGWP） of N2O and CH4 expressed as CO2 equivalent in CT and NT fields, respectively. However, increase in soil CO2 emission indicated that future warming projection might provide positive feedback between soil C release and global warming in NCP.

关键词： Climate warming Greenhouse gas fluxes(N2O CH4 CO2) Conventional tillage No-tillage Soil temperature Soil moisture

Deciphering the role of ultra-low-loaded rhodium in NiFe-MIL-53 for superior oxygen evolution reaction

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Journal of Energy Chemistry 2025年第1期100卷 77-86页

作者： Jinzhi Jia Jinhua zhang Kailu Guo Lanyue zhang Gening Du Hao You Junfeng Huang Mudong tu Hua Li Yong Peng Wei Dou Cailing Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering School of Materials and Energy Lanzhou University College of Chemistry and Chemical Engineering Luoyang Normal University

Designing highly active and stable electrocatalysts of oxygen evolution reaction （OER） is one of the crucial *** this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium（Rh@NiFe-MIL-53）,is successfully prepared via the hydrothermal ***-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active *** importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe（OH）2after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@***,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center （εd）,accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining ***,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity （240 mV） with a small Tafel slope of 48.2 mV dec-1and long-term durability (over1270 h at 10 m A cm-2and 110 h at 200 mA cm-2).This work presents a new perspective on designing highly efficient OER electrocatalysts.

关键词： NiFe-MIL-53 Rh Electrochemical reconstruction Catalytic mechanism Oxygen evolution reaction