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Current Progress of Hf(Zr)-Based High-k Gate Dielectric Thin Films

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Journal of Materials Science & Technology 2007年第4期23卷 433-448页

作者： gang HE Lide zhang Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China　

with the continued downscaling of complementary metal-oxide-semiconductor field effect transistor dimensions, high-dielectric constant （high-k） gate materials, as alternatives to SiO2, have been extensively investigated. Hf （Zr）-based high-k gate dielectric thin films have been regarded as the most promising candidates for high-k gate dielectric according to the International Technology Roadmap for Semiconductor due to their excellent physical properties and performance. This paper reviews the recent progress on Hf （Zr）-based high-k gate dielectrics based on PVD （physical vapor deposition） process. This article begins with a survey of various methods developed for generating Hf （Zr）-based high-k gate dielectrics, and then mainly focuses on microstructure, synthesis, characterization, formation mechanisms of interfacial layer, and optical properties of Hf （Zr）-based high-k gate dielectrics. Finally, this review concludes with personal perspectives towards future research on Hf （Zr）-based high-k gate dielectrics.

关键词： Hf (Zr)-based high-k gate dielectric PVD Optical properties metal-oxide-semiconductor

Symmetry dictionary on charge and spin nonlinear responses for all magnetic point groups with nontrivial topological nature

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national Science Review 2023年第11期10卷 103-109页

作者： Zhi-Fan zhang Zhen-gang Zhu gang Su School of Physical Sciences University of Chinese Academy of Sciences School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of Sciences CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Kavli Institute for Theoretical Sciences University of Chinese Academy of Sciences

Recently, charge or spin nonlinear transport with nontrivial topological properties in crystal materials has attracted much attention. In this paper, we perform a comprehensive symmetry analysis for all 122 magnetic point groups(MPGs) and provide a useful dictionary for charge and spin nonlinear transport from the Berry curvature dipole, Berry connection polarizability and Drude term with nontrivial topological *** results are obtained by conducting a full symmetry investigation of the matrix representations of six nonlinear response tensors. we further identify every MPG that can accommodate two or three of the nonlinear tensors. The present work gives a solid theoretical basis for an overall understanding of the second-order nonlinear responses in realistic materials.

关键词： nonlinear response magnetic point group matrix representation

Deciphering the role of ultra-low-loaded rhodium in niFe-MIL-53 for superior oxygen evolution reaction

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Journal of Energy Chemistry 2025年第1期100卷 77-86页

作者： Jinzhi Jia Jinhua zhang Kailu Guo Lanyue zhang Gening Du Hao You Junfeng Huang Mudong Tu Hua Li Yong Peng wei Dou Cailing Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering School of Materials and Energy Lanzhou University College of Chemistry and Chemical Engineering Luoyang Normal University

Designing highly active and stable electrocatalysts of oxygen evolution reaction （OER） is one of the crucial *** this study,a novel OER electrocatalyst,niFe-MIL-53 modified with ultra-low rhodium（Rh@niFe-MIL-53）,is successfully prepared via the hydrothermal ***-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of niFe-MIL-53 and the in-situ formed Rh@niFeOOH is the actual active *** importantly,the enhanced reversibility of electrochemical reconstruction between niFeOOH and niFe（OH）2after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and ni/Fe in Rh@***,theoretical calculations confirm that the integration of single-atom Rh into the niFeOOH successfully reduces the band gap,regulates the d-band center （εd）,accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining ***,the optimized Rh@niFe-MIL-53 exhibits excellent OER activity （240 mV） with a small Tafel slope of 48.2 mV dec-1and long-term durability (over1270 h at 10 m A cm-2and 110 h at 200 mA cm-2).This work presents a new perspective on designing highly efficient OER electrocatalysts.

关键词： niFe-MIL-53 Rh Electrochemical reconstruction Catalytic mechanism Oxygen evolution reaction

Tangent-impulse transfer from elliptic orbit to an excess velocity vector

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Chinese Journal of Aeronautics 2014年第3期27卷 577-583页

作者： zhang gang zhang Xiangyu Cao Xibin Research Center of Satellite Technology Harbin Institute of Technology national and Local United Engineering Research Center of Small Satellite Technology

The two-body orbital transfer problem from an elliptic parking orbit to an excess veloc-ity vector with the tangent impulse is studied. The direction of the impulse is constrained to be aligned with the velocity vector, then speed changes are enough to nullify the relative velocity. First, if one tangent impulse is used, the transfer orbit is obtained by solving a single-variable function about the true anomaly of the initial orbit. For the initial circular orbit, the closed-form solution is derived. For the initial elliptic orbit, the discontinuous point is solved, then the initial true anomaly is obtained by a numerical iterative approach; moreover, an alternative method is proposed to avoid the singularity. There is only one solution for one-tangent-impulse escape trajectory. Then, based on the one-tangent-impulse solution, the minimum-energy multi-tangent-impulse escape trajectory is obtained by a numerical optimization algorithm, e.g., the genetic method. Finally, several examples are provided to validate the proposed method. The numerical results show that the minimum-energy multi-tangent-impulse escape trajectory is the same as the one-tangent-impulse trajectory.

关键词： Elliptic orbit Escape trajectory Excess velocity vector Orbital transfer Tangent impulse

Autophagy-targeting modulation to promote peripheral nerve regeneration

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neural Regeneration Research 2025年第7期20卷 1864-1882页

作者： Yan Chen Hongxia Deng nannan zhang Department of Obstetrics and Gynecology West China Second HospitalSichuan UniversityChengduSichuan ProvinceChina Key Laboratory of Birth Defects and women and Children’s Diseases Ministry of EducationSichuan UniversityChengduSichuan ProvinceChina Laboratory of Reproductive Endocrinology and Reproductive Regulation Sichuan UniversityChengduSichuan ProvinceChina national Center for Birth Defect Monitoring West China Second University HospitalSichuan UniversityChengduSichuan ProvinceChina

nerve regeneration follow.ng traumatic peripheral nerve injuries and neuropathies is a complex process modulated by diverse factors and intricate molecular *** studies have focused on factors that stimulate axonal outgrowth and myelin ***,recent studies have highlighted the pivotal role of autophagy in peripheral nerve regeneration,particularly in the context of traumatic ***,autophagy-targeting modulation has emerged as a promising therapeutic approach to enhancing peripheral nerve *** current understanding suggests that activating autophagy facilitates the rapid clearance of damaged axons and myelin sheaths,thereby enhancing neuronal survival and mitigating injury-induced oxidative stress and *** actions collectively contribute to creating a favorable microenvironment for structural and functional nerve regeneration.A range of autophagyinducing drugs and interventions have demonstrated beneficial effects in alleviating peripheral neuropathy and promoting nerve regeneration in preclinical models of traumatic peripheral nerve *** review delves into the regulation of autophagy in cell types involved in peripheral nerve regeneration,summarizing the potential drugs and interventions that can be harnessed to promote this *** hope that our review will offer novel insights and perspectives on the exploitation of autophagy pathways in the treatment of peripheral nerve injuries and neuropathies.

关键词： autophagy autophagy related genes Charcot–Marie–Tooth diseases diabetic peripheral neuropathy metformin myelination peripheral nerve injury Schw.nn cells sciatic nerve wallerian degeneration

The dopaminergic system and Alzheimer's disease

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neural Regeneration Research 2025年第9期20卷 2495-2512页

作者： Yuhan zhang Yuan Liang Yixue Gu International Medical College Chongqing Medical UniversityChongqingChina College of Pharmacy Chongqing Medical UniversityChongqingChina Department of neurology The First Affiliated Hospital of Chongqing Medical UniversityChongqing Key Laboratory of NeurologyChongqingChina

Alzheimer's disease is a common neurodegenerative disorder in older *** its prevalence,its pathogenesis remains unclea *** addition to the most widely accepted causes,which in clude excessive amyloid-beta aggregation,tau hyperphosphorylation,and deficiency of the neurotransmitter acetylcholine,numerous studies have shown that the dopaminergic system is also closely associated with the occurrence and development of this *** is a crucial catecholaminergic neurotransmitter in the human ***-associated treatments,such as drugs that target dopamine receptor D and dopamine analogs,can improve cognitive function and alleviate psychiatric symptoms as well as ameliorate other clinical *** r,therapeutics targeting the dopaminergic system are associated with various adverse reactions,such as addiction and exacerbation of cognitive *** review summarizes the role of the dopaminergic system in the pathology of Alzheimer's disease,focusing on currently available dopamine-based therapies for this disorder and the common side effects associated with dopamine-related *** aim of this review is to provide insights into the potential connections between the dopaminergic system and Alzheimer's disease,thus helping to clarify the mechanisms underlying the condition and exploring more effective therapeutic options.

关键词： adverse drug reaction Alzheimer's disease catecholamine dopamine receptor dopamine receptor heterodimers dopaminergic system neurodegenerative disease neurotransmitter signaling pathways traditional Chinese medicine treatment

Gamma-glutamyl transferase 5 overexpression in cerebrovascular endothelial cells improves brain pathology,cognition,and behavior in APP/PS1 mice

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neural Regeneration Research 2025年第2期20卷 533-547页

作者： Yanli zhang Tian Li Jie Miao Zhina zhang Mingxuan Yang Zhuoran w.ng Bo Yang Jiawei zhang Haiting Li Qiang Su Junhong Guo Department of neurology First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of neurology Sixth Hospital of Shanxi Medical University(General Hospital of Tisco)TaiyuanShanxi ProvinceChina Department of Physiology Key Laboratory of Cellular PhysiologyMinistry of EducationShanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Hernia and Abdominal wall Surgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Laboratory Medicine of Fenyang College Shanxi Medical UniversityFenyangShanxi ProvinceChina

In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial ***,the functional role of GGT5 in the development of Alzheimer’s disease remains *** study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying *** observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse ***,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive ***,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 *** effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa *** findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 *** findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease.

关键词： Alzheimer’s disease amyloid-β APP/PS1 mice cerebrovascular endothelial cells cognitive deficits gamma-glutamyl transferase 5 neurovascular unit nuclear factor‐kappa B synaptic plasticity β-site APP cleaving enzyme 1

nanophononic metamaterials induced proximity effect in heat flux regulation

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Frontiers of physics 2024年第2期19卷 149-156页

作者： Jian zhang Haochun zhang gang zhang School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Institute of High Performance Computing Agency for ScienceTechnology and Research(A*STAR)Singapore 138632Singapore

Recent studies have shown that the construction of nanophononic metamaterials can reduce thermal conductivity without affecting electrical properties,making them promising in many fields of application,such as energy conversion and thermal ***,although extensive studies have been carried out on thermal conductivity reduction in nanophononic metamaterials,the local heat flux characteristic is still *** this work,we construct a heat flux regulator which includes a silicon nanofilm with silicon *** regulator has remarkable heat flux regulation ability,and various impacts on the regulation ability are ***,even in the region without nanopillars,the local heat current is still lower than that in pristine silicon nanofilms,reduced by the neighboring nanopillars through the thermal proximity *** combine the analysis of the phonon participation ratio with the intensity of localized phonon modes to provide a clear *** findings not only provide insights into the mechanisms of heat flux regulation by nanophononic metamaterials,but also will open up new research directions to control local heat flux for a broad range of applications,including heat management,thermoelectric energy conversion,thermal cloak,and thermal concentrator.

关键词： nanophononic metamaterials proximity effect

Relative volume comparison of Ricci flow

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Science China Mathematics 2021年第9期64卷 1937-1950页

作者： gang Tian Zhenlei zhang School of Mathematical Sciences and Beijing International Center for Mathematical Research Peking UniversityBeijing 100871China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

In this paper we derive a relative volume comparison of Ricci flow under a certain local curvature *** is a refinement of Perelman’s no local collapsing theorem in Perelman(2002).

关键词： Ricci flow relative volume comparison local entropy

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