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含纳米硅氧化硅薄膜的光致发光特性

华侨大学学报（自然科学版） 2006年第3期27卷 256-258页

作者：杨琳琳郭亨群华侨大学信息科学与工程学院福建泉州362021

利用射频磁控溅射复合靶技术,通过调节复合靶的百分比制得富硅的氧化硅薄膜,并在不同的温度下退火,制得含纳米硅的氧化硅薄膜.通过Raman谱的测量,计算出800℃退火的薄膜中纳米硅晶粒的平均尺寸为5.6 nm,用X射线衍射测量同样的样品得出... 详细信息

利用射频磁控溅射复合靶技术,通过调节复合靶的百分比制得富硅的氧化硅薄膜,并在不同的温度下退火,制得含纳米硅的氧化硅薄膜.通过Raman谱的测量,计算出800℃退火的薄膜中纳米硅晶粒的平均尺寸为5.6 nm,用X射线衍射测量同样的样品得出其粒径为6.0 nm.在室温下测量光致发光(PL)谱,探测样品的峰位为360 nm,并结合光致发光激发谱(PLE),研究相应的激发与发光中心.

关键词：磁控溅射,纳米硅,光致发光氧化硅薄膜

Dirac-harmonic maps with the trivial index

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Science China Mathematics 2024年

作者： Jürgen Jost linlin Sun Jingyong Zhu Max Planck Institute for Mathematics in the Sciences School of Mathematics and Statistics Guangxi Normal University School of Mathematics Sichuan University

For a homotopy class [u] of maps between a closed Riemannian manifold M and a general manifold N, we want to find a Dirac-harmonic map with the map component in the given homotopy class. Most known results require the index to be nontrivial. When the index is trivial, the few known results are all constructive and produce uncoupled solutions. In this paper, we define a new quantity. As a byproduct of proving the homotopy invariance of this new quantity, we find a new simple proof for the fact that all the Dirac-harmonic spheres in surfaces are uncoupled. More importantly, by using the homotopy invariance of this new quantity,we prove the existence of Dirac-harmonic maps from manifolds in the trivial index case. In particular, when the domain is a closed Riemann surface, we prove the short-time existence of the α-Dirac-harmonic map flow in the trivial index case. Together with the density of the minimal kernel, we get an existence result for Dirac-harmonic maps from closed Riemann surfaces to K¨ahler manifolds, which extends the previous result of the first and third authors. This establishes a general existence theory for Dirac-harmonic maps in the context of the trivial index.

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基于BP神经网络模型的新疆水资源承载力情景分析

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北京师范大学学报（自然科学版） 2016年第2期52卷 216-222页

作者：杨琳琳李波付奇北京师范大学资源学院北京100875

水资源可持续利用是科学发展的重要基础,"跨越式"发展愿景下的新疆面临水资源约束的严峻挑战!以2004—2013年水资源统计资料为基础,运用BP神经网络模型模拟分析了2个情景下(情景Ⅰ:趋势外推,情景Ⅱ:跨越式发展)2014—2020年新疆的水资... 详细信息

水资源可持续利用是科学发展的重要基础,"跨越式"发展愿景下的新疆面临水资源约束的严峻挑战!以2004—2013年水资源统计资料为基础,运用BP神经网络模型模拟分析了2个情景下(情景Ⅰ:趋势外推,情景Ⅱ:跨越式发展)2014—2020年新疆的水资源承载力.结果表明:1)水资源承载力综合评价指数呈上升趋势,但情景Ⅰ中水资源开发利用率过高,情景Ⅱ中农业用水比重大、效率低,成为新疆水资源可持续利用的瓶颈;2)以提高水资源的生态效益为目的,提出了情景Ⅲ:可持续利用情景,可逐步解决供需矛盾.关键在于改变传统粗放的用水方式,在提升水资源的利用效率的基础上,优化水资源利用的空间结构以缓和水资源对社会经济发展的瓶颈作用;3)BP神经网络模型与情景分析结合评价新疆水资源承载力是一种可行的尝试.

关键词：水资源承载力 BP神经网络模型情景分析新疆

Self-shrinking supramolecular nanoparticles syndicate energy suppression and NIR-II mild photothermal amplification of mitochondrial oxidative stress for breast cancer therapy

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Nano Research 2024年第5期17卷 4314-4328页

作者： Hongmei Liu Jiming Xu Mengjie Ye Hengbo Zhang linlin Han Jingting Wang Peng Xue Yuejun Kang Zhigang Xu Key Laboratory of Luminescence Analysis and Molecular Sensing Ministry of EducationSchool of Materials and Energy&Chongqing Engineering Research Center for Micro-Nano Biomedical Materials and DevicesSouthwest UniversityChongqing 400715China Key Laboratory of Laser Technology and Optoelectronic Functional Materials of Hainan Province College of Chemistry and Chemical EngineeringHainan Normal UniversityHaikou 571158China Yibin Academy of Southwest University Yibin 644000China

Photothermal therapy(PTT)may lead to healthy tissue damage,tumor metastasis,and recurrence,which makes mild photothermal therapy(mild PTT)stand ***,overcoming heat resistance,insufficient therapeutic effect,and poor photothermal conversion efficiency has become new ***,we report a dynamic supramolecular nanocarrier formed from amide-sericin and aldehyde-polyhydroxy glucan(denoted as SDA),the loose cavity of which can be filled by using the pharmaceutical combination of lonidamine(LND)and NIR-II photothermal agent of IR-1061,producing SDLI with a tighter inner hole,smaller and uniform particle size and excellent stability due to multiple pulling ***,the intricate internal network structure prevents the hydrophobic IR-1061 from forming aggregates in the small cavity,and the photothermal conversion efficiency(PCE)can reach 48.9%.At the acidic tumor microenvironment of pH 6.5,the controlled release of LND can solve the problem of heat resistance of NIR-II mild PTT and significantly improve the therapeutic effect of NIR-II mild ***,SDLI also shows a reasonable tumor inhibition rate,so the synergistic strategy of inhibiting tumor energy metabolism and NIR-II mild PTT to magnify mitochondrial oxidative stress,continuous cell stress state-induced immunogenic cell death to promote the induction of tumor apoptosis is proposed to achieve more effective cancer treatment.

关键词： self-shrinkage dynamic supramolecular nanoparticles tumor energy metabolism NIR-II mild photothermal therapy mitochondrial oxidative stress

税制结构调整的财富分布效应与福利影响——以通过财产税提高直接税比重为例

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财贸经济 2022年第7期43卷 5-20页

作者：吕炜杨林林齐鹰飞东北财经大学经济学院 116025 东北财经大学财政税务学院 116025

提高直接税比重是中国税制结构优化的重要环节。本文构建一个异质性连续时间动态一般均衡模型,在保持宏观税负水平不变的情况下,探讨了间接税比重下降、财产税比重上升的税制结构调整对财富分布和福利的影响,并比较分析了财产税的不同... 详细信息

提高直接税比重是中国税制结构优化的重要环节。本文构建一个异质性连续时间动态一般均衡模型,在保持宏观税负水平不变的情况下,探讨了间接税比重下降、财产税比重上升的税制结构调整对财富分布和福利的影响,并比较分析了财产税的不同征收形式以及税率调整的不同方式导致的政策效果差异。研究表明,当财产税征收面较大时,若通过同等程度增加不同个体税率来提高财产税比重,均可能导致公平和效率的双重损失;在财产税比重较低时,可以在均匀税率下通过仅对高财富人群征税从而以极小的福利损失带来较大的财富不平等程度的改善,而采用累进性财产税税率形式甚至可能实现公平和效率的双重红利;当财产税比重达到一定程度后,继续提高该比重通常会面临公平和效率的尖锐权衡。因此,中国未来可以通过对高财富人群开征适当形式的财产税,以提高直接税比重来实现税制结构优化。

关键词：税制结构财产税财富分布福利

Model reduction of fractional impedance spectra for time–frequency analysis of batteries, fuel cells, and supercapacitors

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Carbon Energy 2024年第1期6卷 108-141页

作者： Weiheng Li Qiu-An Huang Yuxuan Bai Jia Wang linlin Wang Yuyu Liu Yufeng Zhao Xifei Li Jiujun Zhang Institute for Sustainable Energy/College of Sciences Shanghai UniversityShanghaiChina Shanxi Key Laboratory of Nanomaterials and Nanotechnology School of Mechanical and Electrical EngineeringXi'an University of Architecture and TechnologyXi'anShaanxiChina Xi'an Key Laboratory of New Energy Materials and Devices School of Materials Science and EngineeringInstitute of Advanced Electrochemical EnergyXi'an University of TechnologyXi'anShaanxiChina

Joint time–frequency analysis is an emerging method for interpreting the underlying physics in fuel cells,batteries,and *** increase the reliability of time–frequency analysis,a theoretical correlation between frequency-domain stationary analysis and time-domain transient analysis is urgently *** present work formularizes a thorough model reduction of fractional impedance spectra for electrochemical energy devices involving not only the model reduction from fractional-order models to integer-order models and from high-to low-order RC circuits but also insight into the evolution of the characteristic time constants during the whole reduction *** following work has been carried out:(i)the model-reduction theory is addressed for typical Warburg elements and RC circuits based on the continued fraction expansion theory and the response error minimization technique,respectively;(ii)the order effect on the model reduction of typical Warburg elements is quantitatively evaluated by time–frequency analysis;(iii)the results of time–frequency analysis are confirmed to be useful to determine the reduction order in terms of the kinetic information needed to be captured;and(iv)the results of time–frequency analysis are validated for the model reduction of fractional impedance spectra for lithium-ion batteries,supercapacitors,and solid oxide fuel *** turn,the numerical validation has demonstrated the powerful function of the joint time–frequency *** thorough model reduction of fractional impedance spectra addressed in the present work not only clarifies the relationship between time-domain transient analysis and frequency-domain stationary analysis but also enhances the reliability of the joint time–frequency analysis for electrochemical energy devices.

关键词： battery,fuel cell,supercapacitor fractional impedance spectroscopy model reduction time-frequency analysis

Avoiding Sabatier's limitation through pulsed electrocatalysis for enhanced nitrogen oxidation performance

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Journal of Energy Chemistry 2024年第8期95卷 484-489,I0010页

作者： Xiping Guan Zhongfen Nie linlin Zhang Mingxia Guo Chuanwei Shi Chunlei Gu Xia Liu Xin Ding College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071ShandongChina State Key Laboratory of Fine Chemicals Dalian University of Technology(DUT)Dalian 116024LiaoningChina

*** The activation and conversion of the Earth’s abundant inert nitrogen resources into high-value-added products epitomize one of nature’s most critical processes[1-3].Nitric acid(HNO_(3)),as a pivotal industrial raw material,showcases an extensive range of applications and possesses substantial economic value in the production of indispensable chemical compounds[4-6].

关键词： value performance abundant

Cell Mechanics Regulates the Dynamic Anisotropic Remodeling of Fibril Matrix at Large Scale

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Research 2024年第3期2023卷 401-415页

作者： Mingxing Ouyang Yanling Hu Weihui Chen Hui Li Yingbo Ji Linshuo Qiu linlin Zhu Baohua Ji Bing Bu Linhong Deng Institute of Biomedical Engineering and Health Sciences School of Medical and Health Engineering and School of PharmacyChangzhou UniversityChangzhou213164China Institute of Biomechanics and Applications Department of Engineering MechanicsZhejang UniversityHangzhou310027China.

Living tissues often have anisotropic and heterogeneous organizations, in which developmental processes are coordinated by cells and extracellular matrix modeling. Cells have the capability of modeling matrix in long distance;however, the biophysical mechanism is largely unknown. We investigated the dynamic remodeling of collagen I (COL) fibril matrix by cell contraction with designed patterns of cell clusters. By considering cell dynamic contractions, our molecular dynamics simulations predicted the anisotropic patterns of the observed COL bundling in experiments with various geometrical patterns without spatial limitation. The pattern of COL bundling was closely related to the dynamic remodeling of fibril under cell active contraction. We showed that cell cytoskeletal integrity (actin filaments and microtubules), actomyosin contractions, and endoplasmic reticulum calcium channels acting as force generations and transductions were essential for fiber bundling inductions, and membrane mechanosensory components integrin and Piezo played critical roles as well. This study revealed the underlying mechanisms of the cell mechanics-induced matrix remodeling in large scales and the associated cellular mechanism and should provide important guidelines for tissue engineering in potential biomedical applications.

关键词： contraction Dynamic Matrix

Asymmetric time-varying integral barrier Lyapunov function based adaptive optimal control for nonlinear systems with dynamic state constraints

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Frontiers of Information Technology & Electronic Engineering 2024年第6期25卷 887-902页

作者： Yan WEI Mingshuang HAO Xinyi YU linlin OU College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China

This paper investigates the issue of adaptive optimal tracking control for nonlinear systems with dynamic state *** asymmetric time-varying integral barrier Lyapunov function(ATIBLF)based integral reinforcement learning(IRL)control algorithm with an actor–critic structure is first *** ATIBLF items are appropriately arranged in every step of the optimized backstepping control design to ensure that the dynamic full-state constraints are never ***,optimal virtual/actual control in every backstepping subsystem is decomposed with ATIBLF items and also with an adaptive optimized ***,neural networks are used to approximate the gradient value *** to the Lyapunov stability theorem,the boundedness of all signals of the closed-loop system is proved,and the proposed control scheme ensures that the system states are within predefined compact ***,the effectiveness of the proposed control approach is validated by simulations.

关键词： State constraints Asymmetric time-varying integral barrier Lyapunov function(ATIBLF) Adaptive optimal control Nonlinear systems