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A Model Study of Equation of State of QCD at Finite Chemical Potential and Zero Temperature

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Communications in Theoretical Physics 2009年第3期51卷 499-505页

作者： hou feng-yao JIANG Yu SUN Wei-Min ZONG Hong-Shi Department of Physics Nanjing University Nanjing 210093 China Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China joint Center for Particle Nuclear Physics and Cosmology Nanjing 210093 China

In this paper, we give a direct method for calculating the partition function, and hence the equation of state （EOS） of QCD at finite chemical potential and zero temperature. In the EOS derived in this paper the pressure density is the sum of two terms： the first term P（μ）｜μ=0 （the pressure density at μ = 0） is a μ-independent constant; the second term, which is totally determined by G[μ] （p）（the dressed quark propagator at finite μ）, contains all the nontrivial μ-dependence. By applying a general result in the rainbow-ladder approximation of the Dyson-Schwinger approach obtained in our previous study [Phys. Rev. C 71 （2005） 015205], G[μ]（p） is calculated from the meromorphic quark propagator proposed in [Phys. Rev. D 67 （2003） 054019]. From this the full analytic expression of the EOS of QCD at finite μ and zero T is obtained （apart from the constant term P（μ）｜μ=0, which can in principle be caJculated from the CJT effective action）. A comparison between our EOS and the cold, perturbative EOS of QCD of Fraga, Pisarski and Schaffner-Bielich is made. It is expected that our EOS can provide a possible new approach for the study of neutron stars.

关键词： equation of state (EOS) phase transition QCD

Critical Number of Fermion Flavors at Finite Chemical Potential in QED3

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Communications in Theoretical Physics 2005年第6X期44卷 1055-1060页

作者： feng Hong-Tao HE Xiang hou feng-yao SUN Wei-Min ZONG Hong-Shi Department of Physics Nanjing University Nanjing 210093 China Joint Center for Particle Nuclear Physics and Cosmology Nanjing 210093 China CCAST (World Laboratory) P.O. Box 8730 Beijing 100080 China

We propose a new method for calculating the dressed fermion propagator at finite chemical potential in QED3 under the rainbow approximation of Dyson-Schwinger equation. In the above approximation, we show that the dressed fermion propagator at finite chemical potential # has the form S（p） = iγ.p^-A（p^-2）＋ B（ p^-2） with p^-μ= （p^-1p3 ＋ iμ）. Using this form of fermion propagator at nonzero chemical potential, we investigate the Dyson-Schwinger equation for the dressed fermion propagator at finite chemical potential and study the effects of the chemical potential on the critical number of the fermion flavors.

关键词： DS equation chemical potential critical number of the fermion flavors

Calculation of Equation of State of QCD at Finite Chemical Potential and Temperature

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Communications in Theoretical Physics 2008年第5期49卷 1269-1274页

作者： ZONG Hong-Shi hou feng-yao SUN Wei-Min LU Xiao-Fu Department of Physics Nanjing University Nanjing 210093 China Joint Center for Particle Nuclear Physics and Cosmology Nanjing 210093 China Department of Physics Sichuan University Chengdu 610064 China

In this paper, using path integral techniques we derive a model-independent formula for the pressure density P（μ, T）（or equivalently the partition function） of Quantum Chromodynamics （QCD）, which gives the equation of state （EOS） of QCD at finite chemical potential and temperature. In this formula the pressure density P（μ, T） consists of two terms： the first term （p（μ, T）｜T=0） is a μ-independent （but T-dependent） constant; the second term is totally determined by G[μ, T]（p, ωn）（the dressed quark propagator at finite μ and finite T）, which contains all the nontrivial μ-dependence. Then, in the framework of the rainbow-ladder approximation of the Dyson-Schwinger （DS） approach and under the approximation of neglecting the μ-dependence of the dressed gluon propagator, we show that G[μ, T]（p,ωn） can be obtained from G[T]（p,ωn ）（the dressed quark propagator at μ= 0） by the substitution ωn →ωn ＋ iμ. This result facilitates numerical calculations considerably. By this result, once C [T] （p, ωn） is known, one can determine the EOS of QCD under the above approximations （up to the additive term p（μ, T）｜T=0）. Finally, a comparison of the present EOS of QCD and the EOS obtained in the previous literatures in the framework of the rainbow-ladder approximation of the DS approach is given. It is found that the EOS given in the previous literatures does not satisfy the thermodynamic relation ρ（μ,T） =δp（μ,T）/δμ｜T.

关键词： EOS of QCD at finitechemical potential-and temperature phase transition

A Modified Approach for Calculating Dressed Quark Propagator at Finite Chemical Potential

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Communications in Theoretical Physics 2005年第3X期44卷 519-524页

作者： ZONG Hong-Shi CHANG Lei hou feng-yao SUN Wei-Min LIU Yu-Xin Department of Physics Nanjing University Nanjing 210093 China Center for Particle Nuclear Astrophysics Nanjing University Nanjing 210093 China CCAST (World Laboratory) P.O. Box 8730 Beijing 100080 China Department of Physics Peking University Beijing 100871 China

Based on the rainbow approximation of Dyson-Schwinger equation and the assumption that the full inverse quark propagator at finite chemical potential is analytic in the neighborhood of μ = 1, it is proved that the dressed quark propagator at finite chemical potential μ can be written as G0^-1 [μ] =iγ·p↑-A（p↑-^2）＋B（p↑-^2） with p↑-μ= （p↑-p4 ＋iμ）. From the dressed quark propagator at finite chemical potential in Munczek model the bag constant of a baryon and the scalar quark condensate are evaluated. A comparison with previous results is given.

关键词： chemical potential dependence Dyson-Schwinger equation approach

Numerically Solving Quark-Loop Effects on Dressed Gluon Propagator in Chiral Limit

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Communications in Theoretical Physics 2008年第4期49卷 1001-1003页

作者： WANG Jing SHI Yuan-Mei hou feng-yao SUN Wei-Min ZONG Hong-Shi PING Jia-Lun Department of Physics Nanjing Normal University Nanjing 210097 China Department of Physics Nanjing University Nanjing 210093 China Joint Center for Particle Nuclear Physics and Cosmology Nanjing 210093 China School of Physics and Microelectronics Shandong University Jinan 250100 China

We do a numerical calculation on the quark-loop effects on the dressed gluon propagator in the chiral limit. It is found that the quark-loop effects on the dressed gluon propagator are significant in solving the quark propagator in the rainbow approximation of the Dyson-Schwinger equation. The approach we used here is quite general and can also be used to calculate both the chemical potential and current quark mass dependence of the dressed gluon propagator.

关键词： gluon propagator quark-loop effects

氧化铝基陶瓷凝胶注模成型工艺的研究——(I)悬浮体的制备及流变特性

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无机材料学报 1999年第4期14卷 623-629页

作者：张灿英戚凭李镇江侯卫丰侯耀永青岛化工学院高技术陶瓷研究室青岛266042 青岛大学物理系青岛266071

本文研究了单相α Ａｌ２Ｏ３及ＺｒＯ２（３Ｙ）  Ａｌ２Ｏ３复相陶瓷的凝胶注模成型工艺，着重研究了低粘度高固相体积分数浓悬浮体的制备及其固化在碱性条件下，用自制的分散剂ＭＮ制备出固相含量高达６５ｖｏｌ... 详细信息

本文研究了单相α Ａｌ２Ｏ３及ＺｒＯ２（３Ｙ）  Ａｌ２Ｏ３复相陶瓷的凝胶注模成型工艺，着重研究了低粘度高固相体积分数浓悬浮体的制备及其固化在碱性条件下，用自制的分散剂ＭＮ制备出固相含量高达６５ｖｏｌ％、粘度为２６７ｍＰａ·ｓ的α Ａｌ２Ｏ３浓悬浮体，以及低粘度下固相含量达５５ｖｏｌ％的１０ｖｏｌ％ＺｒＯ２（３Ｙ）  Ａｌ２Ｏ３

关键词：凝胶注模成型成型工艺氧化铅陶瓷

Posttraumatic stress symptoms among Chinese university students during the COVID-19 pandemic:Prevalence,correlates,and mental health help-seeking

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World Journal of Psychiatry 2025年第1期15卷 145-152页

作者： Rui-yao Wu Lin-feng Ge Bao-Liang Zhong Department of Psychiatry The Affiliated Wuhan Mental Health CenterTongji Medical College of Huazhong University of Science&TechnologyWuhan 430012Hubei ProvinceChina Department of Psychiatry Wuhan Mental Health CenterWuhan 430012Hubei ProvinceChina

BACKGROUND Revisiting the epidemiology of posttraumatic stress symptoms(PTSSs)among university students during the coronavirus disease 2019(COVID-19)pandemic as well as understanding the mental health help-seeking behavior of individuals with PTSSs has critical implications for public mental health strategies in future medical *** To investigate the prevalence and correlates of PTSSs among university students during the first wave of the COVID-19 pandemic in China and to examine mental health help-seeking behaviors among these *** A total of 2507 Chinese university students were recruited via snowball *** students completed the Seven-item Screening Scale for Post-traumatic Stress Disorder during the first wave of the COVID-19 pandemic in ***-graphic characteristics,pandemic-related characteristics,and mental health help-seeking behaviors of students with PTSSs were also *** The prevalence of PTSSs among the participants was 28.0%.Seven significant correlates of PTSSs were identified(odds ratio=1.23-3.65,P≤0.024):Female sex,being 19 years old or older,living with others or alone,a low level of family economic status,fair or poor interpersonal relationships,severe or very severe local pandemic,and having family members diagnosed with ***,only 3.28%of the students with PTSSs reported seeking help from mental health *** the 23 students who sought help from mental health specialists,13 opted for online or telephone-based psychological *** Our data suggest that there was a high risk of PTSSs among university students and a high level of unmet mental health needs during the COVID-19 *** delivery of mental health services online or via telephone is a promising approach to address these unmet needs.

关键词： Posttraumatic stress symptoms University students COVID-19 Mental health help-seeking China

Nanocarrier-mediated siRNA delivery:a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2538-2555页

作者： Jie Jin Huajing Zhang Qianying Lu Linqiang Tian Sanqiao yao feng Lai Yangfan Liang Chuanchuan Liu Yujia Lu Sijia Tian Yanmei Zhao Wenjie Ren Institute of Disaster and Emergency Medicine Tianjin UniversityTianjinChina Key Laboratory for Disaster Medicine Technology TianjinChina Henan Medical Key Laboratory for Research of Trauma and Orthopedics The Third Affiliated Hospital of Xinxiang Medical UniversityXinxiangHenan ProvinceChina Clinical Medical Center of Tissue Engineering and Regeneration Xinxiang Medical UniversityXinxiangHenan ProvinceChina Institutes of Health Central Plain Xinxiang Medical UniversityXinxiangHenan ProvinceChina School of Public Health Xinxiang Medical UniversityXinxiangHenan ProvinceChina

Traumatic brain injury and Alzheimer's disease share pathological similarities,including neuronal loss,amyloid-βdeposition,tau hyperphosphorylation,blood-brain barrier dysfunction,neuroinflammation,and cognitive ***,traumatic brain injury can exacerbate Alzheimer's disease-like pathologies,potentially leading to the development of Alzheimer's *** offer a potential solution by facilitating the delive ry of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease.U nlike traditional approaches to neuro regeneration,this is a molecula r-targeted strategy,thus avoiding non-specific drug *** review focuses on the use of nanocarrier systems for the efficient and precise delive ry of siRNAs,discussing the advantages,challenges,and future *** principle,siRNAs have the potential to target all genes and non-targetable protein s,holding significant promise for treating various *** the various therapeutic approaches currently available for neurological diseases,siRNA gene silencing can precisely"turn off"the expression of any gene at the genetic level,thus radically inhibiting disease progression;however,a significant challenge lies in delivering siRNAs across the blood-brain *** have received increasing attention as an innovative drug delive ry tool fo r the treatment of brain *** are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier,targeted drug delivery,enhanced drug stability,and multifunctional *** use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective *** this strategy is still in the preclinical exploration stage,it is expected to achieve clinical translation in the future,creating a new field of molecular tar

关键词： blood-brain barrier cognitive dysfunction exosomes gene silencing immunotherapy inorganic nanomaterials liposome nanoparticles neuroinflammation polymer nanoparticles stem cells

An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou feng Ding Yue Hu Jin Zhang Yagang yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory