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Constraints on covariant Horava-Lifshitz gravity from precision measurement of planetary gravitomagnetic field

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Chinese Physics C 2025年第02期 176-184页

作者：张立冬李丽仿徐鹏边星罗子人 School of Physical Science and Technology Lanzhou University Center for Gravitational Wave Experiment National Microgravity LaboratoryInstitute of MechanicsChinese Academy of Sciences Lanzhou Center of Theoretical Physics Lanzhou University Taiji laboratory for Gravitational Wave Universe (Beijing/Hanzhou) University of Chinese Academy of Sciences Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences laboratory of Gravitational Wave Precision Measurement of Zhejiang Province Hangzhou Institute for Advanced StudyUCAS

As a generalization of Einstein's theory, Horava-Lifshitz gravity has attracted significant interest owing to its healthy ultraviolet behavior. In this paper, we analyze the impact of the Horava-Lifshitz corrections on the gravitomagnetic field. We propose a new measurement method for the planetary gravitomagnetic field based on space-based laser interferometry, which is further used to constrain the Horava-Lifshitz parameters. Our analysis shows that high-precision laser gradiometers can indeed limit the parameters in Horava-Lifshitz gravity and improve the results by one or two orders of magnitude compared with the existing theories. Our novel method also provides insights into how to constrain the parameters in the modified gravitational theory to gain deeper understanding of this complex framework and pave the way for potential technological advancements in the field.

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The detection,extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 82-92页

作者： Qianyun Yun Wen-Biao Han Yi-Yang Guo He Wang Minghui Du Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310124China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Taiji laboratory for Gravitational Wave Universe(Beijing/Hangzhou) University of Chinese Academy of SciencesBeijing 100049China Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu ProvinceKey Laboratory of Quantum Theory and Applications of MoELanzhou UniversityLanzhou 730000China Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China International Centre for Theoretical Physics Asia-Pacific(ICTP-AP) University of Chinese Academy of Sciences(UCAS)Beijing 100049China Center for Gravitational Wave Experiment National Microgravity LaboratoryInstitute of MechanicsChinese Academy of SciencesBeijing 100190China

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EM-RIs).This task is particularly challenging because EMRI signals are complex,lengthy,and *** this work,we introduce a 2-layer convolutional neural network(CNN)approach to detect EMRI signals for space-borne detectors,achieving a true positive rate(TPR)of 96.9%at a 1%false positive rate(FPR)for signal-to-noise ratio(SNR)from 50 to ***,the key intrinsic parameters of EMRIs such as the mass,spin of the supermassive black hole(SMBH)and the initial eccentricity of the orbit can also be inferred directly by employing a neural *** mass and spin of the SMBH can be determined at 99%and 92%*** will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform *** study underscores the potential of deep learning methods in EMRI data analysis,enabling the rapid detection of EMRI signals and efficient parameter estimation.

关键词： gravitational wave EMRIs deep-learing

Transition to Film Boiling in microgravity： Influence of Subcooling

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Chinese Physics Letters 2010年第7期27卷 198-201页

作者：赵建福李晶闫娜王双峰 Key laboratory of microgravity (national microgravity laboratory) Institute of Mechanics Chinese Academy of Sciences Beijing 100190

The transition process to film pool boiling in microgravity is studied experimentally aboard the Chinese recoverable satellite S J-8. A quasi-steady heating method is adopted, in which the heating voltage is controlled to increase exponentially with time. Small, primary bubbles are formed and slid on the surface, which coalesce with each other to form a large coalesced bubble. Two ways are observed for the transition from nucleate to film boiling at different subcoolings. At high subcooling, the coalesced bubble with a smooth surface grows slowly. It is then difficult for the coalesced bubble to cover the whole heater surface, resulting in a special region of transition boiling in which nucleate boiling and local dry areas can coexist. In contrast, strong oscillation of the coalesced bubble surface at low subcooling may cause rewetting of local dry areas and activation of more nucleate sites, resulting in an abrupt transition to film boiling.

关键词： FILM boiling REDUCED gravity environments ARTIFICIAL satellites EXTREME environments THERMOPHYSICAL properties HEATING ELECTRIC potential

The impact of N-terminal phosphorylation on LHCII conformation in state transition

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Acta Mechanica Sinica 2014年第3期30卷 447-456页

作者： Jin-Hong Ding Ning Li Man-Liu Wang Yan Zhang Shou-Qin Lü Mian Long Key laboratory of microgravity(national microgravity laboratory)and Center of Biomechanics and Bioengineering Institute of MechanicsChinese Academy of Sciences

State transition is an important protection mechanism of plants for maintaining optimal efficiency through redistributing unbalanced excitation energy between photosystem II （PSII） and photosystem I （PSI）. This process depends on the reversible phosphorylation/dephosphorylation of the major light-harvesting complex II （LHCII） and its bi-directional migration between PSII and PSI. But it remains unclear how phosphorylation/dephosphorylation modulates the LHCII conformation and further regulates its reversible migration. Here molecular dynamics simulations （MDS） were employed to elucidate the impact of phosphorylation on LHCII conformation. The results indicated that N-terminal phosphorylation loosened LHCII trimer with decreased hydrogen bond （H-bond） interactions and extended the distances between neighboring monomers, which stemmed from the conformational ad- justment of each monomer itself. Global conformational change of LHCII monomer started from its stromal N- terminal （including the phosphorylation sites） by enhancing its interaction to lipid membrane and by adjusting the interaction network with surrounded inter-monomer andintra-monomer transmembrane helixes of B, C, and A, and finally triggered the reorientation of transmembrane helixes and transferred the conformational change to luminal side helixes and loops. These results further our understanding in molecular mechanism of LHCII migration during state transition from the phosphorylation-induced microstructural feature of LHCII.

关键词： State transition LHCII Phosphorylation Conformation

The fluid phenomena in the crystallization of the protein crystal

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Chinese Physics B 2008年第8期17卷 3149-3155页

作者：段俐康琦 national microgravity laboratory Institute of Mechanics Chinese Academy of Sciences

This paper reports that an optical diagnostic system consisting of Mach-Zehnder interferometer with a phase shift device and image processor has been used for study of the kinetics of protein crystal growing process. The crystallization process of protein crystal by vapour diffusion is investigated. The interference fringes are observed in real time. The present experiment demonstrates that the diffusion and the sedimentation influence the crystallization of protein crystal which grows in solution, and the concentration capillary convection associated with surface tension occurs at the vicinity of free surface of the protein mother liquor, and directly affects on the outcome of protein crystallization. So far the detailed analysis and the important role of the fluid phenomena in protein crystallization have been discussed a little in both space- and ground-based crystal growth experiments. It is also found that these fluid phenomena affect the outcome of protein crystallization, regular growth, and crystal quality. This may explain the fact that many results of space-based investigation do not show overall improvement.

关键词： convection diffusion sedimentation protein crystal growth

Instability of thermocapillary flow in liquid layers under microgravity

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Science China(Physics,Mechanics & Astronomy) 2012年第4期55卷 684-692页

作者： XUN Bo LI Kai HU WenRui Key laboratory of microgravity(national microgravity laboratory) Institute of MechanicsChinese Academy of SciencesBeijing 100190China

The instability of the thermocapillary flow in liquid layers is studied in the present paper using the linear stability *** on the two-dimensional steady flow state,the three-dimensional disturbance with a wave number in the spanwise direction is *** effects of the aspect ratio and free surface shape of the liquid layer on the flow instability are studied,and the results are compared with the case with the two-dimensional disturbance.

关键词： thermocapillary convection flow instability numerical simulations of chaotic systems

An experimental research on surface oscillation of buoyant-thermocapillary convection in open cylindrical annuli

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Acta Mechanica Sinica 2014年第5期30卷 681-686页

作者： Li Zhang Li Duan Qi Kang national microgravity laboratory Institute of Mechanics Chinese Academy of Sciences

An experiment is carried out on the surface oscillation of buoyant-thermocapillary convection in an open cylindrical annulus. When the radial temperature difference AT reaches a critical value △Tc, a regular oscillation appears and soon disappears on the open surface, which varies when the liquid layer＇s thickness h and temperature difference △T are varied. With growth of △T, dominant frequency of the visible oscillation will grow too but is found within certain frequencies. Driving forces, buoyance and thermocapillarity, are responsible for this phenomanon and the ＂balance＂ point is considered to exist when h is between 4.5-5.0 mm. Surface oscillation region is also found restricted within a narrow gap when Bo is smaller than 3.7.

关键词： Cylindrical annulus Buoyant-thermocapillary convection Surface oscillation Critical temperature differ- ence

Mechanokinetics of receptor-ligand interactions in cell adhesion

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Acta Mechanica Sinica 2015年第2期31卷 248-258页

作者： Ning Li Shouqin Lü Yan Zhang Mian Long Key laboratory of microgravity(national microgravity laboratory) Center of Biomechanics and Bioengineeringand Beijing Key Laboratory of Engineered Construction and MechanobiologyInstitute of MechanicsChinese Academy of Sciences

Receptor-ligand interactions in blood flow are crucial to initiate such biological processes as inflammatory cascade,platelet thrombosis,as well as tumor *** mediate cell adhesion,the interacting receptors and ligands must be anchored onto two apposing surfaces of two cells or a cell and a substratum,i.e.,two-dimensional（2D）binding,which is different from the binding of a soluble ligand in fluid phase to a receptor,i.e.,three-dimensional（3D） *** numerous works have been focused on3 D kinetics of receptor-ligand interactions in the immune system,2D kinetics and its regulations have been less understood,since no theoretical framework or experimental assays were established until *** only does the molecular structure dominate 2D binding kinetics,but the shear force in blood flow also regulates cell adhesion mediated by interacting receptors and ***,we provide an overview of current progress in 2D binding and regulations,mainly from our *** issues of theoretical frameworks,experimental measurements,kinetic rates and binding affinities,and force regulations are discussed.

关键词： Receptor-ligand interactions Selectins β_2 integrins 2D binding kinetics

Gas-liquid phase coexistence and finite-size effects in a two-dimensional Lennard-Jones system

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Chinese Science Bulletin 2011年第26期56卷 2773-2779页

作者： OUYANG WenZe XU ShengHua SUN ZhiWei Key laboratory of microgravity (national microgravity laboratory) Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

The gas-liquid phase coexistence in a two-dimensional Lennard-Jones system is investigated using Maxwell construction method together with molecular dynamics *** results of phase coexistence in different truncations of the potential are compared with data obtained from the literature,and the corresponding critical properties *** crossover from Ising-like to mean field behavior is observed and confirmed as the temperature approaches the critical point from *** simulations on systems with different sizes,we find that a finite size effect is more significant than those shown in most of the previous results,and a lower critical temperature is obtained when the full extent of this finite size effect is considered.

关键词：有限尺寸效应气液相系统二维共存分子动力学模拟规模效应临界温度