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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

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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

A review of the catalytic preparation of mesophase pitch

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新型炭材料（中英文） 2024年第4期39卷 583-610页

作者： MA Zi-hui YANG Tao song Yan CheN Wen-sheng DUAN Chun-feng song Huai-he TIAN Xiao-dong GONG Xiang-jie LIU Zheng-yang LIU Zhan-jun CAS Key Laboratory for Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China College of Material Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Because of its high purity and excellent orientation, mesophase pitch is a superior precursor for high-performance car-bon materials. However, the preparation of top-notch mesophase pitch faces challenges. Catalytic polycondensation at low temperat-ures is more favorable for synthesizing mesophase pitch, because it circumvents the high-temperature free radical reaction of other thermal polycondensation approaches. The reaction is gentle and can be easily controlled. It has the potential to significantly im-prove the yield of mesophase pitch and easily introduce naphthenic characteristics into the molecules, catalytic polycondensation is therefore a preferred method of synthesizing highly spinnable mesophase pitch. This review provides a synopsis of the selective pre-treatment of the raw materials to prepare different mesophase pitches, and explains the reaction mechanism and associated research advances for different catalytic systems in recent years. Finally, how to manufacture high-quality mesophase pitch by using a cata-lyst-promoter system is summarized and proposed, which may provide a theoretical basis for the future design of high-quality pitch molecules.

关键词： Mesophase pitch Catalytic polycondensation Lewis-acid Brønsted acid Catalyst-promoter system

Formation of mesophase microbeads from bulk mesophase pitch induced by fullerene

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新型炭材料（中英文） 2024年第4期39卷 645-654页

作者： CheN Wen-sheng LIU Lan-tao WANG Zheng DUAN Chun-feng ZHANG Xing-wei MA Zhao-kun CheN Xiao-hong song Huai-he State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Electrochemical Process and Technology for MaterialsBeijing Uni-versity of Chemical TechnologyBeijing 100029China

A transformation of naphthalene-based coalescenced mesophase pitch(NMP)to mesophase microbeads was achieved by heating a mixture of NMP and fullerene(C_(60)).This is different from the conventional process of the liquid-phase carbonization of isotropic pitch to the emergence of carbon microbeads in the matrix and finally their growth to form a 100%anisotropic bulk meso-phase,but rather a reverse *** effects of C_(60) loading and reaction temperature on the morphological transformation of mesophase were investigated by polarizing optical and scanning electron *** physical changes in the NMP induced by C_(60) were characterized by thermogravimetric analysis,Fourier transform infrared spectroscopy,X-ray diffractometry and Raman *** results show that the coalesced NMP can be converted to a spherical type at 300-320℃ with the addition of 5%C_(60),and the size of the mesophase microbeads increases with increasing ***,a model is established to ex-plain the unique induction effect of C_(60) in the transformation *** work makes the morphological transformation of MP con-trollable,and provides a new idea for the understanding and research of mesophase pitch.

关键词： Reversible transformation Fullerene induction mechanism Mesophase texture π-electron-induced effect Mesophase microbeads

科技自立自强的历史逻辑、理论内涵与实现路径

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科学管理研究 2024年第1期42卷 2-10页

作者：宋河发刘安琪中国科学院科技战略咨询研究院北京100190 中国科学院大学公共政策与管理学院(知识产权学院) 北京100149

科技自立自强是我国科技事业进入新发展阶段的新目标。纵观我国科技发展史,党的全面领导是实现科技自立自强的根本保证,独立自主和对外开放相统一是基本原则,提升自主创新能力是制度主线,强化国家战略科技力量是客观要求。科技自立自强... 详细信息

科技自立自强是我国科技事业进入新发展阶段的新目标。纵观我国科技发展史,党的全面领导是实现科技自立自强的根本保证,独立自主和对外开放相统一是基本原则,提升自主创新能力是制度主线,强化国家战略科技力量是客观要求。科技自立自强与自力更生和自主创新一脉相承,科技自立自强是指我国能够依靠自身力量创造出适合发展需要的足够数量的高水平科技成果和知识产权,这些科技成果和知识产权能够有效支撑我国产业创新和经济社会发展,强调通过自主研发、自主生产和自主应用来减少对外部科技资源的依赖,从根本上提高自主创新能力和综合国力。为实现科技自立自强,必须坚持党的全面领导,持续深化科技体制改革,进一步完善科技创新政策体系、知识产权严格保护制度、科技创新生态体系和科技评价考核制度,建设科研兴趣导向的高水平科技人才队伍。

关键词：科技自立自强历史逻辑理论内涵实现路径

社会责任同群效应对绿色技术创新的溢出效应研究

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技术经济与管理研究 2024年第6期 104-110页

作者：陈欣宋永和哈尔滨商业大学会计学院黑龙江哈尔滨150028

以沪深A股市场非金融类上市公司为研究样本,运用专家访谈法、回归分析法和内容分析法,研究企业社会责任同群效应对绿色技术创新投资形成的溢出效应。研究结果表明,企业社会责任同群效应对绿色技术创新投资的溢出效应呈“U”型特征;动态... 详细信息

以沪深A股市场非金融类上市公司为研究样本,运用专家访谈法、回归分析法和内容分析法,研究企业社会责任同群效应对绿色技术创新投资形成的溢出效应。研究结果表明,企业社会责任同群效应对绿色技术创新投资的溢出效应呈“U”型特征;动态能力强化了企业社会责任同群效应对绿色技术创新投资的溢出效应,冗余资源和组织惯性缓解了企业社会责任同群效应对绿色技术创新投资的溢出效应。放松企业决策的独立性假设,将同群效应纳入企业社会责任和绿色技术创新研究框架,实现企业社会责任和绿色技术创新的资源合理配置。

关键词：企业社会责任同群效应绿色技术创新投资动态能力冗余资源

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肌肉减少症对肿瘤病人预后的影响和对策

中国实用外科杂志 2024年第2期44卷 172-176页

作者：周建平宋禾中国医科大学附属第一医院胃肠外科疝与腹壁外科辽宁沈阳110001

肌肉减少症(以下简称肌少症)在恶性肿瘤病人中普遍存在,其危害主要是降低综合治疗强度且降低临床疗效、影响精神状况、恶化生活质量,危及生存预后。干预策略主要包括早筛早诊、营养治疗、药物治疗、运动训练、肌电刺激、心理干预等。在... 详细信息

肌肉减少症(以下简称肌少症)在恶性肿瘤病人中普遍存在,其危害主要是降低综合治疗强度且降低临床疗效、影响精神状况、恶化生活质量,危及生存预后。干预策略主要包括早筛早诊、营养治疗、药物治疗、运动训练、肌电刺激、心理干预等。在目前的临床实践中,肿瘤病人的肌少症往往被忽视。更多的医护人员应该予以重视,了解其机制和诊断标准,根据病人的具体情况采取个性化的治疗方案以取得最佳的治疗效果。

关键词：肌肉减少症肿瘤预后营养治疗运动训练心理干预

对相声“肉里噱”和“外插花”理论建构的反思

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民间文化论坛 2024年第4期 133-140页

作者：宋赫中国社会科学院大学文学院

按照是否基于喜剧性情节和人物形象产生的标准,借鉴苏州评弹术语“肉里噱”与“外插花”将相声包袱分类并在价值上厚此薄彼的概念建设肇始于20世纪80年代的曲艺理论热潮,并得到了侯宝林等人的认同和宣介,而后影响深远。这种区分虽源于... 详细信息

按照是否基于喜剧性情节和人物形象产生的标准,借鉴苏州评弹术语“肉里噱”与“外插花”将相声包袱分类并在价值上厚此薄彼的概念建设肇始于20世纪80年代的曲艺理论热潮,并得到了侯宝林等人的认同和宣介,而后影响深远。这种区分虽源于同为曲艺艺术的苏州评弹传统术语,但更多反映了新时期相声重视作品“现实意义”的价值追求,是相声界向“艺术是对现实的能动反映”之类主流话语积极趋近的实践,体现了主流话语对民间艺术的塑造作用,却未必能准确解释这种艺术表达形式的机理。对该知识生产进行反思性研究,于我们突破时代性话语的遮蔽以及把握本体而言是非常必要的。

关键词：相声 “包袱” “肉里噱” “外插花” 现实主义

基于最佳预后元模型的颗粒污垢特性全局敏感性分析

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化工进展 2024年第1期43卷 328-337页

作者：谢广烁张斯亮何松肖娟王斯民西安交通大学化学工程与技术学院陕西西安710049 上海蓝滨石化设备有限责任公司上海201518

通过敏感性分析可识别出重要变量和无关变量,有效筛选数据降低模型复杂程度,并辅助优化设计。以内置转子传热管内的颗粒污垢为研究对象,采用欧拉-欧拉模型和颗粒污垢模型进行数值实验获取训练数据空间,基于最佳预后元模型开展全局敏感... 详细信息

通过敏感性分析可识别出重要变量和无关变量,有效筛选数据降低模型复杂程度,并辅助优化设计。以内置转子传热管内的颗粒污垢为研究对象,采用欧拉-欧拉模型和颗粒污垢模型进行数值实验获取训练数据空间,基于最佳预后元模型开展全局敏感性分析,定量比较了颗粒直径、颗粒浓度、入口流速和入口温度的影响程度。对颗粒污垢四种沉积速率分析表明,入口温度对扩散沉积和热泳沉积的影响最显著,总影响分别为65.4%、58.6%;颗粒直径对湍流泳沉积和重力沉积的影响最明显,总影响分别为53.9%、75.0%。在此基础上,进一步分析了沉积率和污垢热阻的总影响、主影响及交互影响。结果表明:颗粒直径对沉积率和污垢热阻的影响均最大,总影响分别为52.7%、60.2%,各输入变量对沉积率和污垢热阻的交互影响的和分别为59.7%、42.5%,且随着四个输入变量的增加,沉积率和污垢热阻均增大。颗粒直径是影响内置转子传热管颗粒污垢问题的首要因素,在换热器设计中应予以重点考虑,其次是流体温度与流速。

关键词：结垢两相流数值模拟全局敏感性元模型