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Vacuum states on compressible Navier-Stokes equations with general density-dependent viscosity and general pressure law

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Science China Mathematics 2007年第8期50卷 1173-1185页

作者： Mei-man SUN chang-jiang zhu Laboratory of Nonlinear Analysis Department of MathematicsCentral China Normal UniversityWuhan 430079China

In this paper,we study the one-dimensional motion of viscous gas with a general pres- sure law and a general density-dependent viscosity coefficient when the initial density connects to the vacuum state with a *** prove the global existence and the uniqueness of weak solutions to the compressible Navier-Stokes equations by using the line *** this,some new a priori estimates are obtained to take care of the general viscosity coefficientμ(ρ)instead ofρ~θ.

关键词： Navier-Stokes equations density-dependent viscosity vacuum global existence 35Q30 76D05 35B45

Convergence to Diffusion Waves for Nonlinear Evolution Equations with Ellipticity and Damping, and with Different End States

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1357-1370页

作者： chang jiang zhu Zhi Yong ZHANG Hui YIN Laboratory of Nonlinear Analysis Department of Mathematics Central China Normal University Wuhan 430079 P. R. China Department of Mathematical and Statistical Sciences University of Alberta Alberta T6G 2G1 Canada Wuhan Institute of Physics and Mathematics The Chinese Academy of Sciences Wuhan 430071 P. R. China Graduate School of the Chinese Academy of Sciences

In this paper, we consider the global existence and the asymptotic behavior of solutions to the Cauchy problem for the following nonlinear evolution equations with ellipticity and dissipative effects： {ψt=-（1-α）ψ-θx＋αψxx, θt=-（1-α）θ＋νψx＋（ψθ）x＋αθxx（E） with initial data （ψ,θ）（x,0）=（ψ0（x）,θ0（x））→（ψ±,θ±）as x→±∞ where α and ν are positive constants such that α 〈 1, ν 〈 4α（1 - α）. Under the assumption that ｜ψ＋ - ψ-｜＋｜θ＋ - θ-｜ is sufficiently small, we show the global existence of the solutions to Cauchy problem （E） and （I） if the initial data is a small perturbation. And the decay rates of the solutions with exponential rates also are obtained. The analysis is based on the energy method.

关键词： evolution equations diffusion waves decay rate energy method a priori estimates

Direct observation of the scaling relation between density of states and pairing gap in a dirty superconductor

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Chinese Physics B 2021年第10期30卷 463-469页

作者： chang-jiang zhu Limin Liu Peng-Bo Song Han-Bin Deng chang-jiang Yi Ying-Kai Sun R Wu Jia-Xin Yin Youguo Shi Ziqiang Wang Shuheng H.Pan Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China Laboratory for Topological Quantum Matter and Advanced Spectroscopy(B7) Department of PhysicsPrinceton UniversityPrincetonNJUSA Songshan Lake Materials Laboratory Dongguan 523808China Department of Physics Boston CollegeChestnut HillMAUSA

Theories and experiments on dirty superconductors are complex but important in terms of both theoretical fundamentals and practical *** activities are even more challenging when magnetic fields are present because the field distribution,electron density of states,and superconducting pairing potentials become ***,we present tunneling microspectroscopic experiments on NbC single crystals and demonstrate that NbC is a homogeneous dirty *** applying magnetic fields to the samples,we found that the zero-energy local density of states and the pairing energy gap followed the explicit scaling relation proposed by de Gennes for homogeneous dirty superconductors in high magnetic *** significantly,our experimental findings indicate that the validity of the scaling relation extends to magnetic field strengths far below the upper critical field,calling for a new nonperturbative understanding of this fundamental property in dirty *** the practical side,we used the observed scaling relation to derive a simple and straightforward experimental scheme for estimating the superconducting coherence length of a dirty superconductor in magnetic fields.

关键词： NbC dirty superconductor de Gennes theory scanning tunneling microscope

A STUDY ON LOW LEVEL WINDSHEAR HAZARD INDEX

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Chinese Journal of Aeronautics 1993年第2期 95-100页

作者： Jin chang-jiang,Zhang Hong,zhu Ren-biao,Luo Biao,Zhou Wei-bin (Beijing University of Aeronautics and Astronautics,Beijing,China,100083)

One of the key problems of the design of airborne system of low level windshear detection,warning and avoidance is the hazard assessment of low level windshear （LLWS） toaircraft flight. This paper develops theoretically such a hazard index by energy height analysisthat main risk is caused by the horizontal wind acceleration component Uand verticalwind velocity component W. The quantitative and qualitative relationships betweenU, Wand hazard index are studied in detail. It is also attempted to assess thehazard of LLWS to aircraft flight safety based only on the detectable windshear parameterU. This provides the basis for the development of look-forward windshear detectionsensors.

关键词： A STUDY ON LOW LEVEL WINDSHEAR HAZARD INDEX

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng Wang Ruisong zhu Ruijie Liu jiang Ma Lina Hu Weihua Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen chang-jiang Yao Yuan-Yuan zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

AQDS Enhances Degradation of BDE-47 by Promoting Shewanella oneidensis MR-1-mediated Fenton Reaction with Fe(III)-containing Minerals

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Journal of Earth Science 2025年

作者： Yongguang jiang Siqi zhu Zhou jiang Yiran Dong Liang Shi School of Environmental Studies， China University of Geosciences State Key Laboratory of Biogeology and Environmental Geology， China University of Geosciences Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science， China University of Geosciences State Environmental Protection Key Laboratory of Source Apportionment and Control of Aquatic Pollution， Ministry of Ecology and Environment， China University of Geosciences(Wuhan)

Electron shuttles are widespread in the environments and play important role in microbe-mineral interaction. This study investigated the effects of a model electron shuttle (i.e.， anthraquinone-2， 6-disulfonate， AQDS) on Shewanella oneidensis MR-1-mediated Fenton reaction and subsequent degradation of 2， 2′， 4， 4′-tetrabrominated diphenyl ether (BDE-47). Three Fe(III)-containing minerals， namely， ferrihydrite， goethite and nontronite， were used as electron acceptors and Fe(II) sources. With each mineral， additions of 0.01 – 1 mM AQDS in the reactions significantly enhanced Fe(III) reduction by S. oneidensis MR-1 and increased the amounts of Fe(II) produced in anoxic phase. As a result， the amounts of cumulative ·OH formed in oxic phase were increased by 10% – 287%. Regression analysis revealed that ·OH cumulation has significant linear correlation with sorbed Fe(II) but not aqueous and structural Fe(II). This finding may be ascribed to the higher reactivity of sorbed Fe(II) in oxygenation than the latter two types of Fe(II). With more ·OH， the degradation efficiency of BDE-47 was elevated by 31% – 173%. Collectively， AQDS enhances ·OH formation and BDE-47 degradation by promoting production of Fe(II)， particularly sorbed Fe(II) in S. oneidensis MR-1-mediated Fenton reaction with Fe(III)-containing minerals.

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An Approximation Method for Singular Trudinger-Moser Inequality

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应用数学 2025年第1期38卷 64-70页

作者： zhu Maochun XU Wenyan jiang Rou School of Mathematical Sciences Jiangsu UniversityZhenjiang 212013China

In this paper,we construct a power type functional which is the approximation functional of the Singular Trudinger-Moser ***,we obtain the concentration level of the functional and show it converges to the concentrati... 详细信息

关键词： Singular Trudinger-Moser inequality Approximation functional Concentration level

Role of the globus pallidus in motor and non-motor symptoms of Parkinson's disease

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Neural Regeneration Research 2025年第6期20卷 1628-1643页

作者： Yimiao jiang Zengxin Qi Huixian zhu Kangli Shen Ruiqi Liu Chenxin Fang Weiwei Lou Yifan jiang Wangrui Yuan Xin Cao Liang Chen Qianxing zhuang Department of Physiology School of MedicineNantong UniversityNantongJiangsu ProvinceChina Department of Neurosurgery Huashan HospitalShanghai Medical CollegeFudan UniversityShanghaiChina National Center for Neurological Disorders ShanghaiChina Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration ShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institute of Brain ScienceFudan UniversityShanghaiChina

The globus pallidus plays a pivotal role in the basal ganglia circuit. Parkinson's disease is characterized by degeneration of dopamine-producing cells in the substantia nigra, which leads to dopamine deficiency in the brain that subsequently manifests as various motor and non-motor symptoms. This review aims to summarize the involvement of the globus pallidus in both motor and non-motor manifestations of Parkinson's disease. The firing activities of parvalbumin neurons in the medial globus pallidus, including both the firing rate and pattern, exhibit strong correlations with the bradykinesia and rigidity associated with Parkinson's disease. Increased beta oscillations, which are highly correlated with bradykinesia and rigidity, are regulated by the lateral globus pallidus. Furthermore,bradykinesia and rigidity are strongly linked to the loss of dopaminergic projections within the cortical-basal ganglia-thalamocortical loop. Resting tremors are attributed to the transmission of pathological signals from the basal ganglia through the motor cortex to the cerebellum-ventral intermediate nucleus circuit. The cortico–striato–pallidal loop is responsible for mediating pallidi-associated sleep disorders. Medication and deep brain stimulation are the primary therapeutic strategies addressing the globus pallidus in Parkinson's disease. Medication is the primary treatment for motor symptoms in the early stages of Parkinson's disease, while deep brain stimulation has been clinically proven to be effective in alleviating symptoms in patients with advanced Parkinson's disease,particularly for the movement disorders caused by levodopa. Deep brain stimulation targeting the globus pallidus internus can improve motor function in patients with tremordominant and non-tremor-dominant Parkinson's disease, while deep brain stimulation targeting the globus pallidus externus can alter the temporal pattern of neural activity throughout the basal ganglia–thalamus network. Therefore, the comp

关键词： anxiety basal ganglia bradykinesia deep brain stimulation depression globus pallidus externus globus pallidus internus lateral globus pallidus medial globus pallidus neural circuit Parkinson's disease