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Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 136-143页

作者： Di-chao Chen Xie liu Changqing Xu Da-Jian Wu ying Cheng Xiao-Jun liu School of Physics and Technology Nanjing Normal UniversityNanjing 210023China Key Laboratory of Modern Acoustics School of PhysicsNanjing UniversityNanjing 210093China

Vortex transmutation utilizes a periodic system,which not only enables the alteration of the topological charge(TC)of unstable input vortices but also facilitates their transformation into stable *** approach is crucial for investigating the characteristics of vortices in various wave ***,we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES).The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete *** results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures,enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Isolation and Structural Speculation of Herbicide-Active Compounds from the Metabolites of Pythium aphanidermatum

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Journal of Integrative Agriculture 2013年第6期12卷 1026-1032页

作者： ZHANG Li-hui ZHANG Jin-lin liu ying-chao CAO Zhi-yan HAN Jian-min YANG Juan DONG Jin-gao Mycotoxin and Molecular Plant Pathology Lab Agricultural University of Hebei

Natural herbicides, or environment-friendly bioherbicides have been attracted more and more attentions. Isolation and structural identification of natural herbicide-active compounds from plant pathogens has been proved to be an effective approach for novel lead discovery of the pesticide development. In this study, the metabolites of the mutant strain PAM1, which obtained from PA1 of Pythium aphanidermatum （Eds.） Fitzp by ultraviolet radiation were separated and identified by HPLC, NMR, and IR. The results revealed that three active compounds including 4-hydroxy-3-methoxycinnamic acid and two indole derivatives, exhibited inhibition activity on the elongation of radical and coleoptile of Digtaria sanguinalis （L.） Scop.

关键词： herbicidal principles compounds P. aphanidermatum

Gaussian Beams Forward Simulation and Migration

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石油地球物理勘探 2009年第3期44卷 45-51页

作者： Deng Fei liu chao-ying Zhao Bo Wang Cheng-xiang Information Engineering School Chengdu Institute of Technology Chengdu Sichuan Province 610058 China Post Doc Station. BC-P Inc. of CNPC Zhuozhou Hebei Province 072751 China Geophysical Technilogy Research Centre BGP Inc. of CNPC Zhuozhou Hebei Province 072751 China

本文在介绍高斯射线束原理和正演的基础上,从叠后偏移开始分析了高斯射线束偏移的基本原理,并给出了优化的思路和具体的算法流程.高斯射线束是波动方程集中于射线附近的高频近似解,高斯射线束法将射线理论和波动方程方法紧密结合在一起... 详细信息

本文在介绍高斯射线束原理和正演的基础上,从叠后偏移开始分析了高斯射线束偏移的基本原理,并给出了优化的思路和具体的算法流程.高斯射线束是波动方程集中于射线附近的高频近似解,高斯射线束法将射线理论和波动方程方法紧密结合在一起,利用高斯束替代普通射线方法中的射线进行波场正演和延拓,既保持了射线方法的高效性和灵活性,又保留了波场的动力学特征,不仅克服了普通射线方法的一些缺点,而且由于无需两点试射,因而效率非常高.将高斯射线束法引入偏移,利用高斯射线束的性质,可以解决基尔霍夫方法的多值走时问题.模型试算表明,本文介绍的高斯射线束偏移方法能够充分利用高斯射线束的优势,既具有较高的效率又能够获得较好的成像效果.

关键词：高斯光束正向模拟迁移 Kirchhoff方法射线理论波动方程模型试验射线法

The Herbicidal Activity of Mutant Isolates from Botrytis cinerea

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Agricultural Sciences in China 2006年第8期5卷 622-628页

作者： ZHANG Jin-lin ZHANG Li-hui liu ying-chao MA Juan LI Chuan DONG Jin-gao Mycotoxin Laboratory Hebei Agricultural University Baoding 071001 P.R.China

Fifteen mutant isolates were obtained by ultraviolet mutation from parent isolate Botrytis cinerea BC-4. Among them three mutant isolates, BC4-1, BC4-2, and BC4-15, showed strong herbicidal activity. BC4-1 showed maximum herbicidal activity for inhibition of germination and growth of Digitaria sanguinalis L. and Arnaranthus retroflexus L. The results also showed that herbicidal activity was influenced by differing pH of PD media, with pH value of 4.0 being the optimum. The crude toxin was extracted using chloroform, petroleum ether, and ethyl acetate, respectively, and the ethyl acetate extracts showed the strongest inhibitory activity on the germination and growth of D. sanguinalis L. and A. retroflexus L. Using HPLC, one fraction with an absorption peak at 271 nm was separated from the crude toxin. This fraction could strongly inhibit the growth of D. sanguinalis L. at a concentration of 100 mg L^-1 and could completely inhibit the seed germination of D. sanguinalis L. and A. retroflexus L. at a concentration of 50 mg L^-1 .

关键词： Botrytis cinerea toxin ultraviolet mutation herbicide activity separation and purification

对称结构模态振型的Zernike矩描述方法

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振动工程学报 2011年第4期24卷 369-375页

作者：刘银超臧朝平南京航空航天大学能源与动力学院江苏南京210016

讨论了利用Zernike矩描述对称结构模态振型的方法,通过对结构的模态振型数据进行Zernike矩变换,将其分解成一系列Zernike矩的线性组合,而每一个Zernike矩反映模态振型的一部分形状特征。不同特征矩的线性组合,可以代表各阶模态的振型。... 详细信息

讨论了利用Zernike矩描述对称结构模态振型的方法,通过对结构的模态振型数据进行Zernike矩变换,将其分解成一系列Zernike矩的线性组合,而每一个Zernike矩反映模态振型的一部分形状特征。不同特征矩的线性组合,可以代表各阶模态的振型。在此基础上进一步提出了确定Zernike多项式最高阶数的方法,并讨论了Zernike矩描述对称结构模态振型的方法及其去噪声的能力。通过对简单圆盘结构的仿真实例研究,验证了应用Zernike矩描述对称结构模态振型的优越性。结果表明:利用Zernike矩描述对称结构的模态振型可以更有效地描述对称结构的模态,包括重模态,同时还能有效地消除测试数据中噪声的影响,对进一步实现对称结构有限元模型修正和模型确认具有重要的应用价值。

关键词：模态振型 Zernike矩相关性分析滤噪处理重模态

Simulations of electron zebra stripes in the inner radiation belt using a composite empirical electric field model

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Science China Earth Sciences 2025年第1期68卷 27-38页

作者： Ziyang WANG ying liu Qiugang ZONG Hong ZOU Yuguang YE Xuzhi ZHOU chao YUE Shan WANG Institute of Space Physics and Applied Technology Peking UniversityBeijing100871China State Key Laboratory of Lunar and Planetary Science Macao University of Science and TechnologyMacao999078China

The phenomenon termed“zebra stripes”manifests as regular patterns in the energy-space(L shell)spectrum of energetic electrons(ranging from tens to hundreds ke V)within the inner radiation *** structures exhibit drift-periodic behavior and commonly arise from large-scale electric field perturbations near the substorm *** this study,we introduce a composite electric field model and replicate the formation,structure,and evolution of zebra stripes using a bounce-averaged test particle code under this electric field ***-resolution measurements of energetic electrons obtained from the Van Allen Probes and the recently launched Macao Science Satellites-1 are used as initial conditions and served to validate our test particle *** analyses between observed data and simulations demonstrate our test particle method's efficacy in capturing zebra stripes'general ***,the composite model proves capable of reproducing realistic variations in the electric field within the inner radiation belt to a certain ***,subtle differences emerge in the flux strength and the positions of *** disparities primarily stem from limitations inherent in the electric field model and the initial conditions of the *** that the model represents an average case,it is conceivable that real-world scenarios may deviate from the average,thereby introducing variations in the observed phenomena.

关键词： Zebra stripes Inner radiation belt Large-scale electric fields Van Allen Probes Macao Science Satellite

Zonation for exploitation and utilization of geothermal water in Beijing

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Journal of Groundwater Science and Engineering 2014年第3期2卷 94-104页

作者： liu Kai SUN ying LI Yu liu Jiu-rong liu ying-chao Beijing Institute of Hydrogeology and Engineering Geology Beijing Geology and Mineral Resources Exploration and Development Bureau

The geothermal resource type of Beijing belongs to low and middle temperature geothermal resources and the geothermal water has been used for over 40 years. After years of exploitation and utilization,problems such as declining water level,low degree of centralized utilization,lagging reinjection,unreasonable utilization methods etc. Occurred in order to set the reasonable direction of Beijing geothermal resources development and utilization,serve the urban functions as the capital,and build a livable city,the distributive characteristics were summarized in this paper by analyzing the distributive features of geotemperature,the hydrogeochemical characteristics and the characteristics of stable isotope. This paper also put forward zonation for geotemperature,geothermal resources utilization program,and potential for further exploitation and utilization. The study gets the protection zonation of geothermal resources based on the distributive characteristics and the potential zonation. The conclusion will hopefully give us the knowledge and understanding of the characteristics and the recharge areas of the geothermal resources. The results and conclusion have a guiding significance for zonation of geothermal protection and exploitation of geothermal resources.

关键词： Geothermal Hydrochemistry Exploration potential Zonation for exploitation and utilization

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三维射线快速追踪及高斯射线束正演

石油地球物理勘探 2009年第2期44卷 158-165,125+255页

作者：邓飞刘超颖东方地球物理公司博士后科研工作站河北涿州072751 成都理工大学信息工程学院四川成都610059 东方地球物理公司物探技术研究中心河北涿州072751

射线正演方法在复杂地区的地震勘探中起着非常重要的作用,然而随着野外勘探条件复杂程度的增加,三维地质模型也更加复杂化,普通射线正演方法在精度和速度上都不能很好地满足实际生产的需要。为了解决复杂三维介质的地震数值模拟问题,本... 详细信息

射线正演方法在复杂地区的地震勘探中起着非常重要的作用,然而随着野外勘探条件复杂程度的增加,三维地质模型也更加复杂化,普通射线正演方法在精度和速度上都不能很好地满足实际生产的需要。为了解决复杂三维介质的地震数值模拟问题,本文研究了块状三维地质模型的快速射线追踪和高斯射线束正演方法。与普通的射线正演方法不同,该方法将波动方程和射线理论紧密结合起来,通过运动学射线追踪获取射线轨迹,通过动力学追踪获取中心射线附近的高频能量分布,因而既能反映波的运动学特征,又能表现波的动力学特点,并且具有运算速度快、精度高等优点,能够有效地解决复杂三维介质的正演模拟问题。

关键词：射线追踪三角网高斯射线束动力学射线追踪地震记录合成

Bioinspired smart dual-layer hydrogels system with synchronous solar and thermal radiation modulation for energy-saving all-season temperature regulation

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Journal of Energy Chemistry 2025年第2期101卷 175-190页

作者： Meng-Chen Huang chao-Hua Xue Zhongxue Bai Jun Cheng Yong-Gang Wu chao-Qun Ma Li Wan Long Xie Hui-Di Wang Bing-ying liu Xiao-Jing Guo College of Bioresources Chemical and Materials Engineering Shaanxi University of Science & Technology School of Manufacture Science and Engineering Key Laboratory of Testing Technology for Manufacturing Process Ministry of Education Southwest University of Science and Technology School of Life Science and Engineering Southwest University of Science and Technology Northwest Institute for Nonferrous Metal Research Shaanxi Key Laboratory of Biomedical Metal Materials

All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating ***,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature ***,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel) system was subtly created though an "on-demand" dual-layer structure design *** PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating ***,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74) and thermal emissivity(ΔE=0.52) in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃ in summer and 6.1℃ in winter,***,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and *** novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons.

关键词： Energy-saving Radiative cooling Self-adaptive thermal management Spectral modulation Thermochromic hydrogel