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Cosmological interpretation for the stochastic signal in pulsar timing arrays

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 43-50页

作者： Yu-Mei wu Zu-cheng Chen Qing-Guo huang School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Astronomy Beijing Normal UniversityBeijing 100875China Advanced Institute of Natural Sciences Beijing Normal UniversityZhuhai 519087China Department of Physics and Synergistic Innovation Center for Quantum Effects and Applications Hunan Normal UniversityChangsha 410081China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

The pulsar timing array(PTA)collaborations have recently reported compelling evidence for a stochastic signal consistent with a gravitational-wave *** this paper,we combine the latest data sets from NANOGrav,PPTA,and EPTA to explore cosmological interpretations for the PTA signal from first-order phase transitions,domain walls,and cosmic strings,*** find that the domain wall model is strongly disfavored with the Bayes factors compared with the first-order phase transitions and cosmic strings being 1/90 and 1/189,respectively,breaking the degeneracy among these models in individual data *** also find that:(1)a strong phase transition at temperatures below the electroweak scale is favored,and the bubble collisions make the dominant contribution to the energy density spectrum;(2)a small reconnection probability p<1.55×10^(-1)allowed by strings in(super)string theory is favored at the 95%confidence level,and ground-based detectors can further constrain the parameter space.

关键词： puslar timing arrays gravitational-wave background first-order phase transitions domain walls cosmic strings

Strong Limit Theorems for Weighted Sums under the Sub-linear Expectations

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 862-874页

作者： Feng-xiang FENG Ding-cheng WANG Qun-ying wu Hai-wu huang School of Mathematics and Statistics Guilin University of TechnologyGuilin 541004China School of Mathematical Science University of Electronic Science and Technology of ChinaChengdu 611731China School of Science Guilin University of Aerospace TechnologyGuilin 541004China

In this article,we study strong limit theorems for weighted sums of extended negatively dependent random variables under the sub-linear *** establish general strong law and complete convergence theorems for weighted sums of extended negatively dependent random variables under the sub-linear *** results of strong limit theorems are more general than some related results previously obtained by Thrum(1987),Li et al.(1995)and wu(2010)in classical probability space.

关键词： sub-linear expectation complete convergence complete moment convergence the maximal weighted sums

Activatable photoacoustic bioprobe for visual detection of aging in vivo

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Chinese Chemical Letters 2024年第4期35卷 324-329页

作者： Zihong Li Jie cheng Ping huang Guoliang wu Weiying Lin Institute of Optical Materials and Chemical Biology Guangxi Key Laboratory of Electrochemical Energy MaterialsSchool of Chemistry and Chemical EngineeringGuangxi UniversityNanning 530004China

Aging is a natural physiological process with various challenges, related to the loss of homeostasis within the organism, which is not a disease, but a significantly strong risk factor for multiple diseases, including myocardial infarction, stroke, some age-related cancers, macular degeneration, osteoarthritis, neurodegeneration, and many others. In the body, the main manifestation of aging is cellular aging, which exists within tissues and has a local or global impact on tissue function. However, the lack of effective aging detection tools has always been an issue that cannot be ignored in the field of aging research. Therefore,it is necessary to construct a non-invasive tool for in vivo detection of aging. Here, we show that the photoacoustic probe(LGAL), which has peak excitation and emission wavelengths in the near-infrared optical window, binds in vivo and at high contrast to the hallmark of aging, and allows for the microscopic imaging of aging through the intact mice. Firstly, this tool LGAL has been successfully applied to detect senescence in cells, displaying stronger photoacoustic signals than normal cells. Then, by using the photoacoustic probe, the blood vessels and tissues inside the mice can be visualized. Young and elderly mice exhibit varying intensities of photoacoustic signals, marking the first time a probe has been used to explore the aging of blood vessels and tissues inside the mice. Finally, we monitored the changes in the degree of aging during tumor treatment under photoacoustic(PA) imaging for the first time. As the treatment time increased, the degree of aging of the tumor gradually deepened. We expect the powerful tool could be a noninvasive and powerful tool for the study of aging biology.

关键词： Near-infrared Photoacoustic Aging Senescence Tumor Sa-β-gal

Numerical investigation on ball-sealers transport and diversion performance in shale gas horizontal well based on semi-resolved CFD-DEM

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Particuology 2024年第10期93卷 137-153页

作者： Yinjian huang Jinzhou Zhao Lan Ren Ran Lin Jianfa wu cheng Shen Jianjun wu Bing Li National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China Tianfu Yongxing Laboratory Chengdu610213China Shale Gas Research Institute PetroChina Southwest Oil&Gasfield CompanyChengdu610056China PetroChina Coalbed Methane Company Limited Xi’an710082China

In the staged multi-cluster fracturing of shale gas horizontal wells, ball sealers are used to ensure uniform fluid distribution among clusters, a strategy that is both cost-effective and operationally beneficial. Despite these advantages, comprehending the ball sealers' dynamics within the wellbore and their plugging behavior at perforations is still challenging. This complexity results in prediction difficulties regarding their diversion efficiency. To address this, our study utilized a semi-resolved CFD-DEM model based on kernel approximation to simulate the behavior of medium-sized ball sealers in single and multiple cluster scenarios. Our findings from a single cluster scenario reveal that the plugging probability is co-determined by velocity gradients in the fluid ingestion area near the perforation, backflow region, and inertial forces of the ball sealers. As the critical flow rate is achieved, the plugging probability negatively correlated with fluid viscosity and displacement, and positively correlated with the perforation flow ratio (PFR), the difference in particle-fluid density, ball sealer’s diameter, and the ball sealer’s offset from the pipeline center. Temporary plugging control efficiency was used to evaluate the flow balance effect among multiple clusters. The results indicate that an increased number of ball sealers enhances the fault tolerance during the temporary plugging process. Nevertheless, excessive ball sealers might undermine the temporary plugging control efficiency, as perforations with lower fluid inflow rates are unexpectedly plugging. Higher differences in fluid injection rates between clusters led to increased efficiency in temporary plugging control. Premature deployment of ball sealers cannot effectively plug perforations with marginally higher fluid inflow rates, but instead accidently plug intermediate clusters with lower fluid inflow rates. These findings offer a theoretical basis for optimizing the design of ball sealers.

关键词： Gas shale Horizontal wells Ball sealer Semi-resolved CFD-DEM Diversion

Autocatalytic bifunctional supramolecular hydrogels for osteoporotic bone repair

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National Science Review 2024年第7期11卷 263-278页

作者： Zhihui Han Xiang Gao Yuanjie Wang cheng huang Hao Song Shuning cheng Xiaoyuan Yang Xiaoliang Cui Jie wu Kailu Wei Liang cheng Institute of Functional Nano&Soft Materials(FUNSOM) Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow University Department of Orthopedics The Second Affiliated Hospital of Soochow University Macao Institute of Materials Science and Engineering Macau University of Science and Technology

Conventional bone scaffolds, which are mainly ascribed to highly active osteoclasts and an inflammatory microenvironment with high levels of reactive oxygen species and pro-inflammatory factors, barely satisfy osteoporotic defect repair. Herein, multifunctional self-assembled supramolecular fiber hydrogels(Ce–Aln gel) consisting of alendronate(Aln) and cerium(Ce) ions were constructed for osteoporotic bone defect repair. Based on the reversible interaction and polyvalent cerium ions, the Ce–Aln gel, which was mainly composed of ionic coordination and hydrogen bonds, displayed good injectability and autocatalytic amplification of the antioxidant effect. In vitro studies showed that the Ce–Aln gel effectively maintained the biological function of osteoblasts by regulating redox homeostasis and improved the inflammatory microenvironment to enhance the inhibitory effect on osteoclasts. Ribonucleic acid(RNA) sequencing further revealed significant downregulation of various metabolic pathways, including apoptosis signaling,hypoxia metabolism and tumor necrosis factor-alpha(TNF-α) signaling via the nuclear factor kappa-B pathway after treatment with the Ce–Aln gel. In vivo experiments showed that the clinical drug-based Ce–Aln gel effectively promoted the tissue repair of osteoporotic bone defects by improving inflammation and inhibiting osteoclast formation at the defect. Notably, in vivo systemic osteoporosis was significantly ameliorated, highlighting the strong potential of clinical translation for precise therapy of bone defects.

关键词： autocatalysis supramolecular hydrogel anti-inflammation osteoporosis bone defect

Higher-dimensional integrable deformations of the classical Boussinesq-Burgers system

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Communications in Theoretical Physics 2024年第6期76卷 1-12页

作者： Xiaoyu cheng Qing huang School of Mathematics Northwest UniversityXi'an 710127China

In this paper,the(1+1)-dimensional classical Boussinesq-Burgers(CBB)system is extended to a(4+1)-dimensional CBB system by using its conservation laws and the deformation *** Lax integrability,symmetry integrability and a large number of reduced systems of the new higher-dimensional system are ***,for illustration,an exact solution of a(1+1)-dimensional reduced system is constructed from the viewpoint of Lie symmetry analysis and the power series method.

关键词： classical Boussinesq-Burgers system higher-dimensional system deformation algorithm Lax pair conservation law

Quantum phase transition of the Jaynes-Cummings model

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 1-9页

作者： cheng Liu Jin-Feng huang Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsInstitute of Interdisciplinary StudiesHunan Normal UniversityChangsha 410081China

Herein,we propose an experimentally feasible scheme to show the quantum phase transition of the Jaynes-Cummings(JC)model by modulating the transition frequency of a two-level system in a quantum Rabi model with strong *** tuning the modulation frequency and amplitude,the ratio of the effective coupling strength of the rotating terms to the effective cavity(atomic transition)frequency can enter the deep-strong coupling regime,while the counter-rotating terms can be ***,a deep-strong JC model is *** ratio of the coupling strength to resonance frequencies in the deep-strong JC model is two orders of magnitude larger than the corresponding ratio in the original quantum Rabi *** scheme can be employed in atom-cavity resonance and off-resonance cases,and it is valid over a broad *** nonzero average cavity photons of the ground state indicate the emergence of a quantum phase ***,we demonstrate the dependence of the phase diagram on the atom-cavity detuning and modulation *** the parameters used in our scheme are within the reach of current experimental *** scheme provides a new mechanism for investigating the critical phenomena of finite-sized systems without requiring classical field limits,thereby opening a door for studying fundamental quantum phenomena occurring in the ultrastrong and even deep-strong coupling regimes.

关键词： Jaynes-Cummings model quantum phase transition frequency modulation

基于X射线荧光光谱的温稠密物质离化分布实验方法研究

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物理学报 2024年第1期73卷 241-247页

作者：张志宇赵阳青波张继彦林成亮杨国洪韦敏习熊刚吕敏黄成武朱托宋天明赵妍张玉雪张璐李丽灵杜华冰车兴森黎宇坤詹夏宇杨家敏中国工程物理研究院激光聚变研究中心绵阳621900 北京应用物理与计算数学研究所北京100088

受温度及密度等环境效应影响,温稠密物质的电子结构发生显著变化,其理论描述非常复杂,精密实验测量亦极其困难.本文发展了基于X射线荧光光谱研究温稠密物质离化分布的实验方法,结合理论研究有助于深入理解温稠密物质的电子结构变化.在... 详细信息

受温度及密度等环境效应影响,温稠密物质的电子结构发生显著变化,其理论描述非常复杂,精密实验测量亦极其困难.本文发展了基于X射线荧光光谱研究温稠密物质离化分布的实验方法,结合理论研究有助于深入理解温稠密物质的电子结构变化.在万焦耳激光装置上,设计特殊构型黑腔复合加载产生数十eV、近固体密度的稠密Ti物质,利用激光辐照V产生的热发射线泵浦Ti的荧光,并采用晶体谱仪诊断样品的X射线荧光光谱.实验中获得冷样品和加载样品的荧光光谱,观测到加载样品K_(α)及K_(β)荧光谱线相对于冷样品光谱在高能侧的显著变化,结合理论计算解释了加载样品荧光谱线的变化主要来源于其温度上升后离化分布的改变,建立了基于X射线荧光光谱的温稠密物质离化分布实验研究能力.

关键词：温稠密物质电子结构离化分布 X射线荧光光谱

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Study of the Lift Force Induced by An Interceptor on A High-Speed Mono-Hull:The Affecting Factors and Estimation Formula

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China Ocean Engineering 2024年第4期38卷 557-571页

作者： DENG Rui HU Yu-xiao huang Si-chong SONG Zhi-jie WANG Shi-gang wu Tie-cheng School of Ocean Engineering and Technology Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China

To find a better way to estimate the lift force induced by an interceptor on a high-speed mono-hull ship,a series of high-speed mono-hull ship models are designed and investigated under different *** lift forces are obtained by numerical calculations and validated by a model test in a towing *** factors that influence the force are the interceptor height,velocity,draft,and deadrise *** relationship between each factor and the induced lift force is investigated and *** found that the induced lift mainly depends on the interceptor height and advancing velocity,and is proportional to the square of the interceptor height and *** results also showed that the effects of the draft and deadrise angle are relatively less important,and the relationship between the induced lift and these two factors is generally *** on the results,a formula including the combined effect of all factors used to estimate the lift force induced by the interceptor is developed based on systematic *** proposed formula could be used to estimate the lift force induced by interceptors,especially under high-speed condition.

关键词： high-speed mono-hull ship interceptor lift force formula lift force towing tank test computational fluid dynamics