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赋形反射面天线的约束多目标优化设计研究

四川大学学报（自然科学版） 2024年第4期61卷 214-224页

作者：杨承坤王九灵杨小凤杨旋郭庆功四川大学电子信息学院成都610065 南京雷电信息技术有限公司南京210023

赋形反射面天线通常使用单目标优化算法进行设计,当期望波束特性具有多个相互冲突的目标和约束限制时,将无法确保输出最优解.为此,提出了该类天线的约束多目标优化方法 .基于有希望区域优化和自适应约束位移密度估计的思想,设计一种新... 详细信息

赋形反射面天线通常使用单目标优化算法进行设计,当期望波束特性具有多个相互冲突的目标和约束限制时,将无法确保输出最优解.为此,提出了该类天线的约束多目标优化方法 .基于有希望区域优化和自适应约束位移密度估计的思想,设计一种新型双种群协同进化约束多目标优化算法DPBE,在基准测试套件与其他3种主流算法的对比表明,该算法具备更强的全局寻优性与稳定性.将该算法应用于19~21 GHz单偏置抛物反射面天线的平顶波束赋形中,并与单目标优化算法IWO和多目标优化算法NSGA-II-DE在同型初始天线的不同优化模型下进行了性能对比,发现所提方法能在单次运行中满足所有约束条件并取得最佳结果 .

关键词：赋形波束反射面天线约束多目标优化协同进化平顶波束

The First Total Synthesis of Isoliquiritin

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Chinese Chemical Letters 2002年第10期13卷 929-930页

作者： Ya Ping wang Liang Xi LI qing Lian wang Yu Lin LI National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry Lanzhou UniversityLanzhou 730000

A first total synthesis of isoliquiritin was accomplished starting from p-hydroxybenzaldehyde and 2,4-dihydroxyacetylphenone. The key step is condensation reaction. In synthetic process need not protect the hydroxy gr... 详细信息

关键词： Synthesis isoliquiritin flavonoid glycosides.

氮锰共掺生物炭活化过硫酸盐降解安塞蜜的研究

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现代化工 2024年第6期44卷 107-112页

作者：杨威王国相冯清茂陈俊楠余晨晖哈尔滨商业大学食品工程学院黑龙江哈尔滨150028 黑龙江大学化学化工与材料学院功能无机材料化学教育部重点实验室黑龙江哈尔滨150080

考察了高温热解法制备的氮锰共掺生物炭协同过硫酸盐降解水中新兴污染物安塞蜜的效能与机制。表征结果表明,氮锰共掺生物炭具有良好的比表面积与孔径结构。实验结果表明,氮锰共掺生物炭协同过硫酸盐能够显著提升水中安塞蜜的降解率,表... 详细信息

考察了高温热解法制备的氮锰共掺生物炭协同过硫酸盐降解水中新兴污染物安塞蜜的效能与机制。表征结果表明,氮锰共掺生物炭具有良好的比表面积与孔径结构。实验结果表明,氮锰共掺生物炭协同过硫酸盐能够显著提升水中安塞蜜的降解率,表现出更高的降解效能;在催化剂投加质量浓度为2.5 g/L、过硫酸盐浓度为8 mmol/L及不改变初始溶液pH的条件下,120 min时对安塞蜜的去除率高达94.17%。降解反应以硫酸根自由基为主导自由基。氮锰共掺生物炭具有良好的活化性能和回收利用率。

关键词：生物炭过硫酸盐活化硫酸根降解安塞蜜

Synthesis of linear and V-shaped oligo(phenylene ethynylene) derivatives:Geometric effects on photophysical properties

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Chinese Chemical Letters 2010年第1期21卷 97-100页

作者： Yuan, si Chun Han, Shu Liang Ge, Xing wang, Hui Chuan China Agr Univ Fundamental Sci Dept Beijing 102206 Peoples R China Peking Univ Coll Chem Minist Educ Key Lab Bioorgan Chem & Mol Engn Beijing 100871 Peoples R China

A series of linear and V-shaped oligo(phenylene ethynylene) derivatives 1-3 were synthesized through sequent Sonogashira coupling and propargyl alcohol deprotection reaction in high *** alkoxy chains(i.e.,n-hexyloxy groups) were introduced to assure good solubility of compounds 1-3 in common *** photophysical properties of 1-3 in solution depend strongly on the geometries of these compounds.

关键词： Sonogashira coupling Oligo(phenylene ethynylene) derivatives Geometric effect Photophysical property

A new scheme of coded ultrasound using Golay codes

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第6期11卷 476-480页

作者： Cheng JIN si-ping CHEN Zheng-di QIN Tian-fu wang School of Medicine Shenzhen University Shenzhen 518060 China School of Biomedical Engineering and Instrument Science Zhejiang University Hangzhou 310027 China

Golay codes are the most practical code in coded ultrasound imaging *** the trade-off for perfect range sidelobe cancellation is the requirement for two firings, thus resulting in motion-dependent decoding *** view of this, we propose a new scheme using the simultaneous emission of code *** code pair is allocated to different elements of an aperture and transmitted *** process of separating the code pair from the echo received is based on the orthogonality of the code *** last the autocorrelation functions of the individual Golay codes are added *** simultaneous emission of code pairs instead of two firings recovers the frame rate loss, and eliminates the motion-dependent decoding *** theoretical analysis and simulations show that the scheme can be used to eliminate the tissue motion effects.

关键词： Coded ultrasound Golay codes Tissue motion Ultrasonic imaging

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泡沫运动模拟与印花色浆泡沫的稳定性试验

毛纺科技 2024年第8期52卷 26-32页

作者：谭卜鑫汪青郑小佳刘进杨博钧沈委达中原工学院纺织学院河南郑州450007 郑州市绿色染整技术重点实验室河南郑州450007 海西纺织新材料工业技术晋江研究院福建晋江362200

针对泡沫印花所用泡沫稳定性差的问题,使用流体体积法(VOF)和连续表面力(CSF)模型对泡沫运动过程进行模拟,结合试验共同探讨表面张力、液相黏度、气泡间距、气泡直径差对稳定性的影响。结果表明:降低表面张力更有利于在气泡上升过程中... 详细信息

针对泡沫印花所用泡沫稳定性差的问题,使用流体体积法(VOF)和连续表面力(CSF)模型对泡沫运动过程进行模拟,结合试验共同探讨表面张力、液相黏度、气泡间距、气泡直径差对稳定性的影响。结果表明:降低表面张力更有利于在气泡上升过程中维持气泡形状,减少气体扩散,同时能够在试验条件下得到更高的发泡体积;提高液相黏度能够减弱气泡上升过程中的速度,提高泡沫的稳定性;当气泡间距较小时气泡会发生兼并,汇聚成大气泡,缩小气泡直径差距和增大气泡间距能够减弱气泡兼并进程,提高稳定性;使用较高黏度的发泡液制备的泡沫均匀度更高、气泡运动更弱,具有较高的整体稳定性。

关键词：泡沫稳定性模拟仿真 VOF方法发泡性能半衰期

Effects of vegetation type on soil microbial community structure and catabolic diversity assessed by polyphasic methods in North China

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Journal of Environmental Sciences 2007年第10期19卷 1228-1234页

作者： HAN Xue-mei wang Ren-qing LIU Jian wang Meng-cheng ZHOU Juan GUO Wei-hua School of Life Sciences Shandong University Jinan 250100 China Institute of Environment Research Shandong University Jinan 250100 China

Soil microbes play a major role in ecological processes and are closely associated with the aboveground plant community. In order to understand the effects of vegetation type on the characteristics of soil microbial communities, the soil microbial communities were assessed by plate counts, phospholipid fatty acid （PLFA） and Biolog microplate techniques in five plant communities, i.e., soybean field （SF）, artificial turf （AT）, artificial shrub （AS）, natural shrub （NS）, and maize field （MF） in Jinan, Shandong Province, North China. The results showed that plant diversity had little discernible effect on microbial biomass but a positive impact on the evenness of utilized substrates in Biolog microplate. Legumes could significantly enhance the number of cultural microorganisms, microbial biomass, and community catabolic diversity. Except for SF dominated by legumes, the biomass of fungi and the catabolic diversity of microbial community were higher in less disturbed soil beneath NS than in frequently disturbed soils beneath the other vegetation types. These results confirmed that high number of plant species, legumes, and natural vegetation types tend to support soil microbial communities with higher function. The present study also found a significant correlation between the number of cultured bacteria and catabolic diversity of the bacterial community. Different research methods led to varied results in this study. The combination of several approaches is recommended for accurately describing the characteristics of microbial communities in many respects.

关键词： Biolog legume microbial biomass plant diversity phospholipid fatty acid (PLFA) soil microbes

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金属有机框架材料的制备及应用研究进展

化工新型材料 2024年第1期52卷 65-70页

作者：庆达王建省苏新悦赵英娜曾雄丰华北理工大学材料科学与工程学院河北省无机非金属材料实验室唐山063210 河北省(唐山)陶瓷产业技术研究院唐山063007

金属-有机框架(MOFs)是一种由金属离子团簇和有机配体通过配位键桥连形成的多孔晶态材料,具有高孔隙率、高比表面积、易于功能化修饰等特点,在气体吸附、催化、传感、医药等方面都具有潜在的应用价值。然而,MOFs材料的不同合成方法往往... 详细信息

金属-有机框架(MOFs)是一种由金属离子团簇和有机配体通过配位键桥连形成的多孔晶态材料,具有高孔隙率、高比表面积、易于功能化修饰等特点,在气体吸附、催化、传感、医药等方面都具有潜在的应用价值。然而,MOFs材料的不同合成方法往往会直接影响材料形貌并导致其性能差异,通过改变合成方法,能够显著改变材料性能并应用于不同领域。综述总结了近年来MOFs材料的多种合成方法及其典型应用进展,并探讨了不同合成方法的优缺点,最后对其未来发展趋势进行了展望。

关键词：金属有机框架合成方法催化吸附传感

(Metal yolk)/(porous ceria shell)nanostructures for high-performance plasmonic photocatalysis under visible light

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Nano Research 2020年第5期13卷 1354-1362页

作者： Nina Jiang Danyang Li Lili Liang qing Xu Lei Shao Shi-Bin wang Aizheng Chen Jianfang wang College of Chemical Engineering Huaqiao UniversityXiamen 361021China Department of Physics The Chinese University of Hong KongShatinHong Kong SARChina Country Fujian Provincial Key Laboratory of Biochemical Technology(Huaqiao University) Xiamen 361021China

We describe a route to the preparation of(metal yolk)/(porous ceria shell)nanostructures through the heterogeneous growth of ceria on porous metal nanoparticles followed by the calcination-induced shrinkage of the *** approach allows for the control of the ceria shell thickness,the metal yolk composition and size,which is difficult to realize through common templating *** yolk/shell nanostructures with monometallic Pt and bimetallic PtAg yolks featuring plasmon-induced broadband light absorption in the visible region are rationally designed and *** superior photocatalytic activities of the obtained nanostructures are demonstrated by the selective oxidation of benzyl alcohol under visible *** excellent activities are ascribed to the synergistic effects of the metal yolk and the ceria shell on the light absorption,electron-hole separation and efficient mass *** synthesis of the(metal yolk)/(porous ceria shell)nanostructures points out a way to the creation of sophisticated heteronanostructures for high-performance photocatalysis.

关键词： yolk-shell nanostructures ceria metal nanoparticles plasmon resonance photocatalysis