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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 *** construct a holographic model describing the gluon sector of QCD at finite temperatures in the non-perturbative *** equation of state as a function of temperature is in good accordance with the lattice QCD ***,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 *** obtain a strong first-order confinement/deconfinement phase transition at Tc=276.5 Me V that is consistent with the lattice QCD *** 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 *** 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

Changes in microstructure and properties of weld heat-affected zone of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第8期31卷 2041-2052页

作者： Shu-jun Jia Qi-lin Ma Yu Hou Ba Li he-song Zhang Qing-you Liu Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Collaborative Innovation Center for Steel Commonality University of Science and Technology BeijingBeijing 100083China Construction Project Management Branch of China National Petroleum Pipeline Network Group Co. Ltd.Langfang 065000HebeiChina

The evolution of the microstructure and toughness of APL5L X80 pipeline steel after thermal welding simulation was investigated by X-ray diffraction,electron backscatter diffraction,and transmission electron *** results indicated that primary heat-affected zones can be divided into weld,coarse-grained,fine-grained,intercritical,and sub-critical *** microstructure of the weld zone is mainly composed of bainitic ferrite and a small amount of granular bainite;however,the original austenite grains are distributed in the columnar *** structure of the coarse-grained zone is similar to that of the weld zone,but the original austenite grains are *** contrast,the microstructure in the fine-grained zone is dominated by fine granular bainite,and the effective grain size is only 8.15μm,thus providing the highest toughness in the entire heat-affected *** intercritical and subcritical zones were brittle valley regions,and the microstructure was dominated by granular ***,the martensite-austenite(M/A)constituents are present in island chains along the grain boundaries,and the coarse size of the M/A constituents seriously reduces the *** results of the crack propagation analyzes revealed that high-angle grain boundaries can significantly slow down crack growth and change the crack direction,thereby increasing the material *** impact toughness of the low-temperature tempering zone was equivalent to that of the columnar grain zone,and the impact toughness was between those of the critical and fine-grained zones.

关键词： Welding thermal simulation Impact toughness Crack propagation Martensite-austenite constituent High-strength low-alloy steel weld heat-affected zone

Carbon capture in power sector of China towards carbon neutrality and its comparison to renewable power

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Fundamental Research 2024年第4期4卷 916-925页

作者： Sheng Li Lin Gao song he Dongtai Yang Chaowei Wang Yawen Zheng School of mechanical engineering Beijing Institute of TechnologyBejing 100081China Laboratory of Integrated Energy System and Renewable Eery Institute of Engineering ThemophysicsChinese Academyof SciencesBejing0010China

CO_(2)capture from coal power plants is an important and necessary solution to realizing carbon neutrality in China,but ccs demonstration deployment in power sector is far behind ***,the reduction potential of energy consumption and cost for CcS and its competitiveness to renewable powers are very important to make roadmaps and policies toward carbon *** the popular recognition that capturing CO_(2)from flue gases is technically and commercially mature,this paper notes that it has been proved to be technically feasible but far beyond technology maturity and high energy penalty leads to its immaturity and therefore causes high ***,the potential energy penalty reduction of capture is investigated thermodynamically,and future CO_(2)avoidance cost is predicted and compared to renewable power(solar PV and onshore wind power).Results show that energy penalty for CO_(2)capture can be reduced by 48%-57%.When installation capacity reaches a similar scale to that of solar PV in China(250 GW),CO_(2)capture cost in coal power plants can be reduced from the current 28-40 USs/ton to 10-20 USs/ton,and efficiency upgrade contributes to 67%-75%in cost reduction for high coal price *** China,CO_(2)capture in coal power plants can be cost competitive with solar PV and onshore wind *** it is worth noting that the importance and share of CCS role in CO_(2)emission reduction is decreasing since renewable power is already well deployed and there is still a lack of large-scale CO_(2)capture demonstrations in *** capture technologies with low energy penalties need to be developed to promote *** in this work can provide informative references for making roadmaps and policies regarding CO_(2)emission reductions that contribute towards carbon neutrality.

关键词： Carbon capture and storage Carbon neutrality Energy consumption Fluegas Renewable energy

Decreased soil pH weakens the positive rhizosphere effect on denitrification capacity

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Pedosphere 2024年第5期34卷 905-915页

作者： Jun WANG Zongxiang ZHANG Fei LIANG Zhao Che Yongkang WEN Manyu ZHANG Wenjun JIN Zhaorong DONG he song College of Agronomy Anhui Agricultural University Key Laboratory of Arable Land Quality Monitoring and Evaluation Ministry of Agriculture and Rural Affairs Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences (CAAS) College of Resources and Environmental Sciences China Agricultural University

The stimulating effect of rhizosphere on denitrification is considered to be an unavoidable loss of soil nitrogen（N） and detrimental to crop N use efficiency,which is regulated by crop growth and soil properties. Soil acidification, occurring rapidly in many intensive farming lands, affects both crop growth and soil properties, thereby altering rhizosphere effect on denitrification. However, the mechanism by which soil acidification regulates rhizosphere denitrification still remains unclear. here, we determined the denitrification capacity（DC） and associated community compositions of nirK-and nirS-type denitrifiers in maize rhizosphere and bulk soils at four acidity gradients（pH = 6.8, 6.1, 5.2, and 4.2）. Results showed that the stimulating effect of rhizosphere on DC strongly depended on soil pH. Compared to bulk soil, rhizosphere soil had significantly higher DC at pH 5.2, but not at pH of 4.2. With increasing soil acidity, the stimulation of rhizosphere on DC（calculated as the difference in DC between rhizosphere and bulk soils） decreased from 8.01 to 0.01 mg N ***, soil acidification significantly reduced the differences in dissolved organic carbon（DOC） and abundance of key nirK-type denitrifier taxa between rhizosphere and bulk soils, both of which were positively related to the stimulation of rhizosphere on DC. These findings demonstrated that soil acidification could weaken the positive rhizosphere effect on denitrification via regulated C availability and associated nirK-type denitrifier community, potentially reducing N loss risk in rhizosphere soil. The independent role of soil p H should be fully considered when modelling N behaviour in plant-soil systems.

关键词： bacterial abundance denitrifier community dissolved organic carbon operational taxonomic unit soil acidification

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： song he Li Li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

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Graph based recurrent network for context specific synthetic lethality prediction

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Science China Life Sciences 2024年

作者： Yuyang Jiang Jing Wang Yixin Zhang ZhiWei Cao Qinglong Zhang Jinsong Su song he Xiaochen Bo Academy of Medical Engineering and Translational Medicine Tianjin University Department of Bioinformatics Institute of Health Service and Transfusion MedicineBeijing School of Medicine Tsinghua University School of Informatics Xiamen University

The concept of synthetic lethality (SL) has been successfully used for targeted therapies. To further explore SL for cancer therapy, identifying more SL interactions with therapeutic potential are essential. Recently, graph neural network-based deep learning methods have been proposed for SL prediction, which reduce the SL search space of wet-lab based methods. However, these methods ignore that most SL interactions depend strongly on genetic context, which limits the application of the predicted results. In this study, we proposed a graph recurrent network-based model for specific context-dependent SL prediction (SLGRN). In particular, we introduced a Graph Recurrent Network-based encoder to acquire a context-specific, low-dimensional feature representation for each node, facilitating the prediction of novel SL. SLGRN leveraged gate recurrent unit (GRU) and it incorporated a context-dependent-level state to effectively integrate information from all nodes. As a result, SLGRN outperforms the state-of-the-arts models for SL prediction. We subsequently validate novel SL interactions under different contexts based on combination therapy or patient survival analysis. Through in vitro experiments and retrospective clinical analysis, we emphasize the potential clinical significance of this context-specific SL prediction model.

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Advances in the studies of the supported ruthenium catalysts for CO_(2)methanation

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Chinese Journal of Catalysis 2024年第8期63卷 1-15页

作者： Chenyang Shen Menghui Liu song he Haibo Zhao Chang-jun Liu Collaborative Innovation Center of Chemical Science&Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China Key Laboratory of Mesoscopic Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023JiangsuChina State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan430074HubeiChina

CO_(2)methanation has a potential in the large-scale utilization of carbon *** has also been considered to be useful for the renewable energy *** commercial pipeline for natural gas transportation can be directly applied for the methane product of CO_(2)*** supported ruthenium(Ru)catalyst has been confirmed to be active and stable for CO_(2)methanation with its high ability in the dissociation of hydrogen and the strong binding of carbon ***_(2)methanation over the supported Ru catalyst is structure *** size of the Ru catalyst and the support have significant effects on the activity and the mechanism.A significant challenge re-mained is the structural controllable preparation of the supported Ru catalyst toward a sufficiently high low-temperature *** this review,the recent progresses in the investigations of the supported Ru catalysts for CO_(2)methanation are *** challenges and the future devel-opments are also discussed.

关键词： Ruthenium Carbon dioxide Methanation Hydrogenation Catalyst and metal-support interaction

Digital generation of super-Gaussian perfect vortex beams via wavefront shaping with globally adaptive feedback

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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

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基于注意力机制的高容量通用图像隐写模型

软件学报 2024年第3期35卷 1502-1514页

作者：袁超王宏霞何沛松四川大学网络空间安全学院四川成都610065

随着深度学习与隐写技术的发展,深度神经网络在图像隐写领域的应用越发广泛,尤其是图像嵌入图像这一新兴的研究方向.主流的基于深度神经网络的图像嵌入图像隐写方法需要将载体图像和秘密图像一起输入隐写模型生成含密图像,而最近的研究... 详细信息

随着深度学习与隐写技术的发展,深度神经网络在图像隐写领域的应用越发广泛,尤其是图像嵌入图像这一新兴的研究方向.主流的基于深度神经网络的图像嵌入图像隐写方法需要将载体图像和秘密图像一起输入隐写模型生成含密图像,而最近的研究表明,隐写模型仅需要秘密图像作为输入,然后将模型输出的含密扰动添加到载体图像上,即可完成秘密图像的嵌入过程.这种不依赖载体图像的嵌入方式极大地扩展了隐写的应用场景,实现了隐写的通用性.但这种嵌入方式目前仅验证了秘密图像嵌入和恢复的可行性,而对隐写更重要的评价标准,即隐蔽性,未进行考虑和验证.提出一种基于注意力机制的高容量通用图像隐写模型USGAN,利用注意力模块,USGAN的编码器可以在通道维度上对秘密图像中像素位置的扰动强度分布进行调整,从而减小含密扰动对载体图像的影响.此外,利用基于CNN的隐写分析模型作为USGAN的目标模型,通过与目标模型进行对抗训练促使编码器学习生成含密对抗扰动,从而使含密图像同时成为攻击隐写分析模型的对抗样本.实验结果表明,所提模型不仅可以实现不依赖载体图像的通用嵌入方式,还进一步提高了隐写的隐蔽性.

关键词：图像隐写注意力机制生成对抗网络对抗样本