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Gravitational waves and primordial black hole productions from gluodynamics by holography

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 31-42页

作者： song he Li Li Zhibin Li Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Max Planck Institute for Gravitational Physics(Albert Einstein Institute) Golm 14476Germany CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China

Understanding the nature of quantum chromodynamics(QCD)matter is important but challenging due to the presence of nonperturbative dynamics under extreme conditions.We construct a holographic model describing the gluon sector of QCD at finite temperatures in the non-perturbative regime.The equation of state as a function of temperature is in good accordance with the lattice QCD data.Moreover,the Polyakov loop and the gluon condensation,which are proper order parameters to capture the deconfinement phase transition,also agree quantitatively well with the lattice QCD data.We obtain a strong first-order confinement/deconfinement phase transition at Tc=276.5 Me V that is consistent with the lattice QCD prediction.Based on our model for a pure gluon hidden sector,we compute the stochastic gravitational waves and primordial black hole(PBH)productions from this confinement/deconfinement phase transition in the early Universe.The resulting stochastic gravitational-wave backgrounds are found to be within detectability in the International Pulsar Timing Array and Square Kilometre Array in the near future when the associated productions of PBHs saturate the current observational bounds on the PBH abundances from the LIGO-Virgo-Collaboration O3 data.

关键词： AdS/QCD confinement/deconfinement phase transition gravitational wave primordial black hole

digital micromirror device;flat-top beam;orbital angular momentum;perfect vortex beam;random fiber laser

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High Power Laser Science and Engineering 2024年第1期12卷 42-51页

作者： Rui Ma Ke Hai Luo Jing song he Wei Li Zhang Dian Yuan Fan Anderson S.L.Gomes Jun Liu International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhenChina Institute for Advanced Study Shenzhen UniversityShenzhenChina Fiber Optics Research Centre School of Information and Communication EngineeringUniversity of Electronic Science and Technology of ChinaChengduChina Departamento de Física Universidade Federal de PernambucoRecife-PEBrazil

High-intensity vortex beams with tunable topological charges and low coherence are highly demanded in applications such as inertial confinement fusion(ICF) and optical communication. However, traditional optical vortices featuring nonuniform intensity distributions are dramatically restricted in application scenarios that require a high-intensity vortex beam owing to their ineffective amplification resulting from the intensity-dependent nonlinear effect. here, a low-coherence perfect vortex beam(PVB) with a topological charge as high as 140 is realized based on the super-pixel wavefront-shaping technique. More importantly, a globally adaptive feedback algorithm(GAFA) is proposed to efficiently suppress the original intensity fluctuation and achieve a flat-top PVB with dramatically reduced beam speckle contrast. The GAFA-based flat-top PVB generation method can pave the way for high-intensity vortex beam generation,which is crucial for potential applications in ICF, laser processing, optical communication and optical trapping.

关键词： digital micromirror device flat-top beam orbital angular momentum perfect vortex beam random fiber laser

Reduction potential of the energy penalty for CO_(2) capture in CCS

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Frontiers in Energy 2023年第3期17卷 390-399页

作者： Yawen ZheNG Lin GAO song he Hongguang JIN Laboratory of Integrated Energy System and Renewable Energy Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

CO_(2) capture and storage(CCS)has been acknowledged as an essential part of a portfolio of technologies that are required to achieve cost-effective long-term CO_(2) mitigation.However,the development progress of CCS technologies is far behind the targets set by roadmaps,and engineering practices do not lead to commercial deployment.One of the crucial reasons for this delay lies in the unaffordable penalty caused by CO_(2) capture,even though the technology has been commonly recognized as achievable.From the aspects of separation and capture technology innovation,the potential and promising direction for solving this problem were analyzed,and correspondingly,the possible path for deployment of CCS in China was discussed.Under the carbon neutral target recently proposed by the Chinese government,the role of CCS and the key milestones for deployment were indicated.

关键词： CO_(2)capture and storage(CCS) CO_(2)separation energy penalty

Genus two correlation functions in CFTs with TT deformation

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Science China(Physics,Mechanics & Astronomy) 2023年第5期66卷 106-119页

作者： song he Yun-Ze Li Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Max Planck Institute for Gravitational Physics(Albert Einstein Institute) Am Mühlenberg 114476 GolmGermany

Since the definition of TT deformation in the curved Riemann surface is obstructive in the literature,we propose a way to do the deformation in the genus two Riemann surfaces by sewing prescription.We construct the correlation functions of conformal field theories(CFTs)on genus two Riemann surfaces with the TT deformation in terms of the perturbative CFT approach.Thanks to sewing construction to form higher genus Riemann surfaces from lower genus ones and conformal symmetry,we systematically obtain the first-order TT correction to the genus two correlation functions in the TT deformed CFTs,e.g.,partition function and one/higher-point correlation functions.

关键词： conformal field theory gauge/gravity duality TT deformation higher genus correlation function

Insight into pyrolysis of hydrophobic silica aerogels:Kinetics,reaction mechanism and effect on the aerogels

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Chinese Journal of Chemical Engineering 2023年第6期58卷 266-281页

作者： Xinyu Liu Hongliang Sheng song he Chunhua Du Yuansheng Ma Chichi Ruan Chunxiang he Huaming Dai Yajun Huang Yuelei Pan School of Safety Science and Emergency Management Wuhan University of TechnologyWuhan 430070China Wuhan Building Material Industry Design&Research Institute Co. LtdWuhan 430200China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230027China

Silica aerogels have promising applications in thermal insulation,but their flammability and reaction mechanisms have rarely been investigated.The pyrolysis kinetics and thermodynamics of hydrophobic silica aerogels under N_(2) environment were studied.The kinetic and thermodynamic parameters were obtained by three model-free methods.Based on the calculated kinetic parameters,the pyrolysis mechanism of silica aerogels was discussed by the master plots method.The results indicate that the reactions of the whole pyrolysis phase can be characterized by a random nuclear model.In addition,FTIR test results show that the volatile products of silica aerogel pyrolysis are mainly hydrocarbons generated by the decomposition of hydrophobic groups(methyl groups)on the surface.Finally,the effects of pyrolysis on the properties of silica aerogels Finally,the effects of pyrolysis on the properties of silica aerogels were investigated based on the analysis results of SEM,specific surface area,pore size distribution,X-ray diffraction,XPS and infrared spectroscopy.

关键词： Pyrolysis Thermodynamics Reaction kinetics

Note on higher-point correlation functions of the TT or JT deformed CFTs

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Science China(Physics,Mechanics & Astronomy) 2021年第9期64卷 15-28页

作者： song he Center for Theoretical Physics College of PhysicsJilin UniversityChangchun 130012China Max Planck Institute for Gravitational Physics(Albert Einstein Institute) Am M¨uhlenberg 1Golm 14476Germany

We investigate generic n-point correlation functions of conformal field theories(CFTs),with TT and JT deformations,in terms of the perturbative CFT approach.We systematically obtain the first order correction to the generic correlation functions of CFTs with TT or JT deformation.We compute the out of time ordered correlation function(OTOC)in the Ising model with TT or Jdeformation,which confirms that these deformations do not change the integrable property up to the first order level.

关键词： integrable deformation conformal field theory quantum chaos quantum integrability quantum entanglement

Genus two correlation functions in CFTs with T■ deformation

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Science China(Physics,Mechanics & Astronomy) 2023年第5期 110-123页

作者： song he Yun-Ze Li Center for Theoretical Physics and College of Physics Jilin University Max Planck Institute for Gravitational Physics (Albert Einstein Institute)

Since the definition of T■ deformation in the curved Riemann surface is obstructive in the literature, we propose a way to do the deformation in the genus two Riemann surfaces by sewing prescription. We construct the correlation functions of conformal field theories(CFTs) on genus two Riemann surfaces with the T■ deformation in terms of the perturbative CFT approach. Thanks to sewing construction to form higher genus Riemann surfaces from lower genus ones and conformal symmetry, we systematically obtain the frst-order T■ correction to the genus two correlation functions in the T■ deformed CFTs, e.g., partition function and one/higher-point correlation functions.

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Synergistic engineering of cobalt selenide and biomass-derived S,N,P co-doped hierarchical porous carbon for modulation of stable Li-S batteries

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Journal of Materials Science & Technology 2023年第3期134卷 11-21页

作者： Yang Lin song he Zhiyong Ouyang Jianchao Li Jie Zhao Yanhe Xiao Shuijin Lei Baochang Cheng Nanoscale Science and Technology Laboratory Institute for Advanced StudyNanchang UniversityNanchang 330031China School of Physics and Materials Nanchang UniversityNanchang 330031China

Hierarchical porous carbon co-doped with heterogeneous atoms has attracted much attention thanks to sizable internal void space accommodating electrolyte,high-density microporous structure physically con-fining polysulfides(LPS),and heterogeneous atoms serving as active sites to capture LPS.However,solely relying on carbon material defects to capture LPS proves ineffective.hence,metal compounds must be introduced to chemisorb LPS.herein,cobalt ions are in-situ grown on the polydopamine layer coated on the surface of biomass-derived S,N,P co-doped hierarchical porous carbon(SNP-PC).Then a layer of nitrogen-doped porous carbon(MPC)dotted with CoSe nanoparticles is acquired by selenizing.Thus,a strong-polar/weak-polar composite material of SNP-PC studded with CoSe nanoparticles is obtained(SNP-PC@MPC@CoSe).Button cells assembled with SNP-PC@MPC@CoSe-modified separator enable superb long-cycle stability and satisfactory rate performance.An excellent rate capacity of 796 mAh g^(−1)at a high current rate of 4 C with an ultra-low capacity fading of 0.06%over 700 cycles can be acquired.More impressively,even in a harsh test condition of 5.65 mg cm^(−2)sulfur loading and 4μL mg^(−1)ratio of electrolyte to active materials,the battery can still display a specific capacity of 980 mAh g^(−1)(area capacity of∼5.54 mAh cm^(−2))at 0.1 C.This work provides a promising route toward high-performance Li-S batteries.

关键词： Lithium-sulfur battery Biomass conversion S,N,P-codoped porous carbon CoSe modulation Multifunctional separator Synergism of strong and weak polarity

Role of CCUS in carbon neutral power system

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碳中和(英文) 2022年第1期1卷 377-388页

作者： Yawen Zheng Lin Gao Rui Dong song he Laboratory of Integrated Energy System and Renewable Energy Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China North China Electric Power University Beijing 100096China

Achieving carbon neutrality by 2060 is an ambitious goal to promote the green transition of economy and society in China.Highly relying on coal and contributing nearly half of CO_(2) emission,power industry is the key area for reaching carbon-neutral goal.On basis of carbon balance,a criterial equation of carbon neutral for power system is provided.By means of the equation,the different effects of three technical approaches to achieve carbon neutrality,including energy efficiency improvement,shifting energy structure and CO_(2) capture,utilization and storage(CCUS)technology,had been evaluated.The results indicate that building a carbon-neutral power system requires comprehensive coordination between energy efficiency,renewable energy and CCUS technology.In particular,the unique role of CCUS in achieving carbon neutral target was investigated.For any power systems with fossil energy input,CCUS and negative emission technologies is indispensable to reach carbon neutrality.However,rather high energy consumption and costs is the critical gas deterring the large scale deployment of CCUS.Considering the specific conditions of China’s power industry,before the time window between 2030 and 2040 being closed,CCUS would either be ready for large scale deployment by reducing energy consumption and costs,or be phased out along with the most coal power plants.Conclusively,carbon neutral scenario will give CCUS the last chance to decarbonize the fossil fuel,which has great significance for China.

关键词： Carbon neutrality CCUS Power system Carbon emission intensity