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风场及光伏电场配置对阵列风沙结构影响的模拟分析

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北京林业大学学报 2017年第8期39卷 68-76页

作者：陈曦高永娜仁格日勒翟波王余彦史万林内蒙古农业大学沙漠治理学院锡林郭勒盟镶黄旗苗圃中国电建集团北京勘测设计研究院有限公司锡林郭勒盟镶黄旗林政资源管理站

以对比分析不同风场及电站配置模式下光伏阵列对风沙输移的影响差异为研究目的,通过风洞模拟实验对不同风速、风向、电站阵列行距及是否布设麦草沙障时阵列在0~50 cm内的输沙情况进行分析,并对风沙流结构进行了探讨。结果表明:1)在0~50... 详细信息

以对比分析不同风场及电站配置模式下光伏阵列对风沙输移的影响差异为研究目的,通过风洞模拟实验对不同风速、风向、电站阵列行距及是否布设麦草沙障时阵列在0~50 cm内的输沙情况进行分析,并对风沙流结构进行了探讨。结果表明:1)在0~50 cm高度范围内,阵列模型的输沙率与风速大小呈正比,与集沙高度呈反比,3个试验风速下输沙率均以多项式拟合关系最佳;2)当风向为南风时阵列输沙率及其风沙流结构特征值(λ)最高,南风(180°)、东北风(45°)、西北风(315°)的输沙最佳拟合函数分别为多项式函数、对数函数和指数函数;3)当阵列行距为20 cm时(以野外电场为原型等比例缩小值)阵列输沙率最高;4)当阵列前端布设麦草沙障后阵列风沙流结构特征值(λ)为1.75,即此时风沙流呈不饱和状态,具有挟沙能力。

关键词：光伏阵列风速风向行间距麦草沙障

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高原环境爆炸冲击波传播规律及计算模型研究

火工品 2025年第1期 62-69页

作者：赵伟成翟红波李尚青毛伯永西安近代化学研究所陕西西安710065

为研究高原地区的低温低压环境对冲击波传播特性的影响,在海拔1500,3000,4500 m环境下开展了TNT爆炸试验,并使用有限元软件对高原环境TNT的爆炸冲击波进行数值仿真计算,分析了不同海拔对冲击波传播特性的影响规律。对比了Sadovskyi,Kinn... 详细信息

为研究高原地区的低温低压环境对冲击波传播特性的影响,在海拔1500,3000,4500 m环境下开展了TNT爆炸试验,并使用有限元软件对高原环境TNT的爆炸冲击波进行数值仿真计算,分析了不同海拔对冲击波传播特性的影响规律。对比了Sadovskyi,Kinney-Graham和Sachs修正公式的超压峰值和比冲量计算结果与试验结果,并采用Sachs修正中的温度修正项对Sadovskyi高原超压峰值公式进行了修正。研究结果表明:随着海拔的升高,冲击波的波阵面速度加快,到达时间提前,每升高1 km,冲击波超压峰值下降约2%~4%,比冲量下降约4%;对超压峰值进行修正时,3种修正公式均具有一定的准确性;对比冲量进行修正时,Kinney-Graham修正的比冲量值随比例距离增加呈线性降低,与试验结果吻合较差,庞春桥与Sachs的修正结果随比例距离增加呈指数降低;基于温度项修正的Sadovskyi高原冲击波超压峰值经验公式的平均误差减小了3.1%。该研究结果对于高海拔地区的弹药毁伤效能评估有参考意义。

关键词：爆炸试验高原环境冲击波传播特性计算模型

Copper-Catalyzed Si-H bond Insertion Polymerization for Synthesis of Optically Active Polyesters Containing Silicon

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Chinese Journal of Chemistry 2022年第1期40卷 21-27页

作者： Xiao-yong zhai Xiao-Qing Wang bo Wu yong-Gui Zhou State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The synthesis and characterization of chiral polymers with diverse structure remain a long-term challenging research ***,a copper-catalyzed enantioselective insertion of carbene into Si-H bond was applied to polycondensation,giving a new type of optically active degradable polyesters containing Si-C bond in the main *** polymerization features mild condition,broad substrate scope,excellent yields and *** diols could be obtained via reduction of optically active *** analysis indicated these chiral polyesters exhibit good thermal stability.

关键词： Polymerization Insertion Asymmetric catalysis Optically active polyesters Copper

Unraveling the mechanism of action of Shangxia Liangji formula for treating insomnia:a metabolomics and network pharmacology approach

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Traditional Medicine Research 2025年第2期10卷 16-29页

作者： Xia-Jie Quan Hao Liang yong-Hong Tang Li Jiang Xiong-Ying Ji Feng-Ying Zhang Ping Zhang bo Ouyang Department of Information The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of Neurology The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of Gastroscopy The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of Traditional Chinese Medicine The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China

Background:Insomnia is a prevalent clinical condition and Shangxia Liangji formula(SXLJF)is a well-established method of ***,the specific mechanism of action of SXLJF remains ***:The mouse model of insomnia was established by intraperitoneal injection of ***-two mice were randomly divided into a negative control group,model group,SXLJF group(18.72 g/kg/day),and positive control group(diazepam,2 mg/kg)and treated with the corresponding drugs for 7 consecutive *** open field test and pentobarbital-induced sleeping test were ***-MS-based untargeted metabolomics and network pharmacology were applied to explore the potential targets of SXLJF for treating ***,key targets were validated using ***:Behavioral tests demonstrated that SXLJF reduced the total distance,average velocity,central distance,and sleep latency,and prolonged sleep *** and network pharmacology revealed potential targets,signaling pathways,metabolic pathways,and metabolites associated with the anti-insomnia effects of ***,tyrosine hydroxylase(TH)and tyrosine metabolism emerged as crucial metabolic pathways and targets,***-qPCR results supported the role of TH in the mechanism of SXLJF in treating ***:In conclusion,TH and tyrosine metabolism may represent significant targets and pathways for SXLJF in treating insomnia.

关键词： Shangxia Liangji formula insomnia metabolomics network pharmacology tyrosine hydroxylase tyrosine metabolism

Van der Waals gap engineering in 2D materials for energy storage and conversion

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Rare Metals 2024年第12期43卷 6125-6143页

作者： Qian Chen Yi Wei Peng-bo zhai yong-Ji Gong School of Materials Science and Engineering Beihang University State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Tianmushan Laboratory Xixi Octagon City

Since the discovery of two-dimensional(2D)materials,they have garnered significant attention from researchers owing to the exceptional and modifiable physical and chemical *** weak interlayer interactions in 2D materials enable precise control over Van der Waals gaps,thereby enhancing their performance and introducing novel *** regulating the Van der Waals gap,2D materials exhibit a diverse range of applications in the field of energy storage and *** article provides a comprehensive review of various methods for manipulating Van der Waals gaps in 2D materials,including interlayer intercalation,guest atom doping within the lattice,formation of Van der Waals heterojunctions,and adjustment of stacking ***,the impacts of these manipulations on energy storage and conversion applications are also ***,potential future research directions are proposed to shed light on advancements in Van der Waals gap engineering.

关键词： Heterojunctions

Observer-based control for the platform of a tethered space robot

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Chinese Journal of Aeronautics 2018年第8期31卷 1786-1796页

作者： Guang zhai Heming ZHENG bo ZHANG Aerospace Engineering School Beijing Institute of TechnologyBeijing 100081China Aerospace System Engineering Shanghai Shanghai 201109China

This paper addresses the attitude control problem of a space tethered robot platform in the presence of unknown external disturbance caused by a connecting elastic tether. The tethergenerated unknown disturbance leads to tremendous challenges for attitude control of the *** this work, the perturbed attitude dynamics of the platform are derived with a consideration of the libration of the elastic tether, and then with the purpose of compensating the unknown disturbance, major attention is dedicated to develop a nonlinear disturbance observer based on gyros measurements, after which, an adaptive attitude scheme is proposed by combining the disturbance observer with a sliding mode controller. Finally, benefits from the observer based on an adaptive controller are validated by series of numerical simulations.

关键词： Adaptive control Attitude dynamics Disturbance observerSliding mode controlTethered space robot

Multiple Positive Solutions for Semi-positone m-point boundary Value Problems

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Acta Mathematicae Applicatae Sinica 2011年第3期27卷 419-426页

作者： Cheng-bo zhai Cheng Yang School of Mathematical Science Shanxi University Shanxi 030006 China Business College of Shanxi University Shanxi 030031 China

In this article, we establish the existence of at least two positive solutions for the semi-positone m-point boundary value problem with a parameter u （t）＋ λf （t, u） = 0, t ∈ （0, 1）, u （0） = sum （biu （ξ i ）） from i=1 to m-2, u（1）= sum （aiu（ξ i ）） from i=1 to m-2, where λ 〉 0 is a parameter, 0 〈 ξ 1 〈 ξ 2 〈 ··· 〈 ξ m 2 〈 1 with 0 〈sum ai from i=1 to m-2 〈 1, sum bi from i=1 to m-2 =1 b i 〈 1, a i , b i ∈ [0, ∞） and f （t, u） ≥ M with M is a positive constant. The method employed is the Leggett-Williams fixed-point theorem. As an application, an example is given to demonstrate the main result.

关键词： Multiple positive solutions cone semi-positone m-point boundary value problem,concave functional parameter

A hardware/software co-optimization approach for embedded software of MP3 decoder

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 42-49页

作者： ZHANG Wei LIU Peng zhai Zhi-bo Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

In order to improve the efficiency of embedded software running on processor core, this paper proposes a hard-ware/software co-optimization approach for embedded software from the system point of view. The proposed stepwise methods aim at exploiting the structure and the resources of the processor as much as possible for software algorithm optimization. To achieve low memory usage and low frequency need for the same performance, this co-optimization approach was used to optimize embedded software of MP3 decoder based on a 16-bit fixed-point DSP core. After the optimization, the results of decoding 128 kbps, 44.1 kHz stereo MP3 on DSP evaluation platform need 45.9 MIPS and 20.4 kbytes memory space. The optimization rate achieves 65.6% for memory and 49.6% for frequency respectively compared with the results by compiler using floating-point computation. The experimental result indicates the availability of the hardware/software co-optimization approach depending on the algorithm and architecture.

关键词： Hardware/software co-optimization DSP Embedded software MP3 decoder

A Multiple-Relaxation-Time Lattice boltzmann Model for Natural Convection in a Hydrodynamically and Thermally Anisotropic Porous Medium under Local Thermal Non-Equilibrium Conditions

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Journal of Thermal Science 2020年第3期29卷 609-622页

作者： YANG bo WU Wei LI Maodong zhai Wei Guangzhou Special Pressure Equipment Inspection and Research Institute Guangzhou 510663China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China

To investigate the natural convective process in a hydrodynamically and thermally anisotropic porous medium at the representative elementary volume(REV)scale,the present work presented a multiplerelaxation-time lattice boltzmann method(MRT-LBM)based on the assumption of local thermal non-equilibrium conditions(LTNE).Three sets of distribution function were used to solve the coupled momentum and heat transfer *** set was used to compute the flow field based on the generalized non-Darcy model;the other two sets were used to solve the temperature fields of fluid and solid under the *** describe the anisotropy of flow field of the porous media,a permeability tensor and a Forchheimer coefficient tensor were introduced into the ***,a heat conductivity tensor and a special relaxation matrix with some off-diagonal elements were selected for the thermal ***,by selecting an appropriate equilibrium moments and discrete source terms accounting for the local thermal non-equilibrium effect,as well as choosing an off-diagonal relaxation matrix with some specific elements,the presented model can recover the exact governing equations for natural convection under LTNE with anisotropic permeability and thermal conductivity with no deviation terms through the Chapman-Enskog ***,the proposed model was adopted to simulate several benchmark *** agreements with results in the available literatures can be achieved,which indicate the wide practicability and the good accuracy of the present model.

关键词： lattice boltzmann method natural convection in anisotropic porous medium local thermal non-equilibrium