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Dramatical enhancement of circular dichroism in chiral hybrid perovskites via carboxylic hydrogen bond engineering

Science China Chemistry 2025年

作者： Hang Li Xinling Li Peng Wang Tingting Zhu Ruiqing Li Huang Ye Yaru Geng hongliang dai Junhua Luo State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Fujian College University of Chinese Academy of Sciences College of Chemistry Fuzhou University College of Chemistry and Materials Key Laboratory of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of EducationJiangxi Normal University

Chiral hybrid perovskites （CHPs） have been regarded as promising candidates for developing chiroptoelectronics ***,circular dichroism （CD）,as one of the most important characteristics to evaluate the chiroptical activity,remains at a comparatively low level in CHPs compared to other chiral materials,which hinders the successful applications of CHPs in stateof-the-art ***,exploring new methods for enhancing CD in CHPs is urgently needed and remains ***,enhanced CD response has been successfully realized via constructing carboxylic hydrogen bonding in chiralachiral mixed cations perovskites （R/S-PPA）2（ABA）PbBr5（2R/2S）(PPA=1-phenylpropylamine,ABA=4-aminobutyric acid).Compared with the prototype （R/S-PPA）PbBr3（1R/1S）,2R/2S provide intimate connections between organic units and inorganic parts via carboxylic hydrogen bonding N–H···O bridge,contributing new chirality transfer paths.A larger inorganic skeletons’helicity in 2R/2S predicts a high degree of chirality ***,2R/2S exhibit significantly enhanced CD response with an anisotropy factor amplified by an order of ***,bright blue circularly polarized luminescence applications are achieved in 2R/*** work systematically investigates the correlation between CD and hydrogen bonding interaction in CHPs,meanwhile providing a new avenue to develop the application potential of chiral materials in chiroptoelectronics.

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MECHANICAL AND ACOUSTIC RESPONSE OF AN UNDERWATER STRUCTURE SUBJECTED TO MECHANICAL EXCITATION

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Acta Mechanica Solida Sinica 2014年第3期27卷 284-299页

作者： Xuetao Weng Shijian Zhu hongliang dai Yiming Fu Yiqi Mao Institute of Noise & Vibration Naval University of Engineering Department of Engineering Mechanics College of Mechanical & Vehicle Engineering Hunan University

In this paper, an underwater structure is modeled as a cylindrical shell with internal bulkheads, and closed by a truncated conical shell, and it consists of metal substrate and sound absorbing coating, whose FGM core is considered. Suppose the inner cavity and outer space of the structure are filled with air and fluid mediums, the mechanical response of the underwater structure is calculated with Galerkin method while the acoustic response is investigated by means of the Helmholtz integral. Some numerical examples are given and the effect of geometrical size and material parameters on mechanical and acoustic response is discussed.

关键词： underwater structure acoustic response functionally graded material boundary element method Helmholtz integral formula

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A Novel Momentum-Based Measure for Online Portfolio Algorithm

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Journal of Computer and Communications 2024年第9期12卷 1-21页

作者： Xiaoting Lv Cuiyin Huang hongliang dai School of Economics and Statistics Guangzhou University Guangzhou China

In recent years, digital investment portfolios have become a significant area of interest in the field of machine learning. To tackle the issue of neglecting the momentum effect in risk asset prices within the follow-the-winner strategy and to evaluate the significance of this effect, a novel measure of risk asset price momentum trend is introduced for online investment portfolio research. Firstly, a novel approach is introduced to quantify the momentum trend effect, which is determined by the product of the slope of the linear regression model and the absolute value of the linear correlation coefficient. Secondly, a new investment portfolio optimization problem is established based on the prediction of future returns. Thirdly, the Lagrange multiplier method is used to obtain the analytical solution of the optimization model, and the soft projection optimization algorithm is used to map the analytical solution to obtain the investment portfolio of the model. Finally, experiments are conducted on five benchmark datasets and compared with popular investment portfolio algorithms. The empirical findings indicate that the algorithm we are introduced is capable of generating higher investment returns, thereby establishing its efficacy for the management of the online investment portfolios.

关键词： Machine Learning Online Portfolio Selection Momentum Effect Significance Algorithmic Trading

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智能拉普拉斯分类器

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中山大学学报（自然科学版） 2009年第2期48卷 14-19页

作者：戴宏亮广东商学院数学与计算科学学院广东广州510320

针对拉普拉斯分类器的核参数选择问题,通过首先假设窗的三个估计中核参数取不同的值,然后运用智能遗传算法对核参数进行优选,得到一种新的分类器——智能拉普拉斯分类器。多个基准数据集上的实验结果证明,智能拉普拉斯分类器相对普通拉... 详细信息

针对拉普拉斯分类器的核参数选择问题,通过首先假设窗的三个估计中核参数取不同的值,然后运用智能遗传算法对核参数进行优选,得到一种新的分类器——智能拉普拉斯分类器。多个基准数据集上的实验结果证明,智能拉普拉斯分类器相对普通拉普拉斯分类器和支持向量机而言,具有较高的分类精度和稳定性,是一种有效的分类方法。

关键词：核方法拉普拉斯分类器支持向量机智能遗传算法

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基于ITAFSVM的微阵列数据特征选择和分类

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中山大学学报（自然科学版） 2010年第2期49卷 37-42,47页

作者：戴宏亮广东商学院数学与计算科学学院广东广州510320

支持向量机已经被成功应用于基因表达谱数据分析。但是,仍有开放问题需要解决:①支持向量机不能自动进行基因表达谱数据的特征选择;②支持向量机的参数优选没有简单有效的办法。一种新型具有良好特性的支持向量机——全间隔自适应模糊... 详细信息

支持向量机已经被成功应用于基因表达谱数据分析。但是,仍有开放问题需要解决:①支持向量机不能自动进行基因表达谱数据的特征选择;②支持向量机的参数优选没有简单有效的办法。一种新型具有良好特性的支持向量机——全间隔自适应模糊支持向量机(TAFSVM)被提出。并且提出一种新的遗传算法——智能遗传算法(IGA)来设计一个TAFSVM分类器,称为ITAFSVM,同时优化TAFSVM参数集和特征选择,并且结合10-fold交叉验证来确定其泛化能力。最后将ITAFSVM应用于四种基因表达谱数据集。通过与进化支持向量机(ESVM)方法、粗糙集与径向基神经网络组合(RBF-RBFNN)方法进行了比较,实验结果表明运用ITAFSVM不仅可以自动进行基因表达谱数据特征选择,而且分类精度和稳定性都较高,速度更快。

关键词：全间隔自适应模糊支持向量机智能遗传算法基因表达谱分类微阵列

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FROM THE EDITORS

FROM THE EDITORS

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2013全国压电和声波理论及器件技术研讨会

作者： Xu Han hongliang dai Weiqiu Chen Hunan University Zhejiang University

＜正＞This proceeding contains 100 papers selected from the presentations at the 2013 Symposium on Piezoelectricity,Acoustic Waves and Device Applications（SPAWDA 2013）,which was successfully held during October 25-27,2013 at Hunan Hotel,Changsha,*** is an interdisciplinary,multi-field,and industry-focused technical forum with international flavor,which has been rapidly growing in recent *** on the analyses,design,and applications of piezoelectric devices,the objective of

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汉译“通名”统一规范化的原则及意义——以壮傣语支语言为例

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语言文字应用 2005年第2期 22-28页

作者：戴红亮教育部语言文字应用研究所北京100010

针对少数民族语地名通名汉译混乱的现象,文章以壮傣语支地名通名为例,提出语音对应原则、统一汉字原则、层次原则、通专名分译原则和避免成词原则,以期从更高层次上规范少数民族语地名。在此基础上,文章还阐述了统一规范的意义和价值。

关键词：语音对应统一汉字层次通专名分译避免成词

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含孔隙变厚度FG圆板的湿热力学响应

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力学学报 2019年第2期51卷 512-523页

作者：戴婷戴宏亮李军剑贺其湖南大学机械与运载工程学院长沙410082

功能梯度材料(functionally graded materials,FGM)是组份含量按特定方向连续变化的非均匀复合材料,可有效解决传统复合材料组份之间结合能力弱和不同组份性能难以协调等问题,达到诸如缓和应力集中和优化应力分布等效果,使整体材料在保... 详细信息

功能梯度材料(functionally graded materials,FGM)是组份含量按特定方向连续变化的非均匀复合材料,可有效解决传统复合材料组份之间结合能力弱和不同组份性能难以协调等问题,达到诸如缓和应力集中和优化应力分布等效果,使整体材料在保持细观结构完整性的同时充分发挥各组份材料的性能优势.由于制备技术等原因或出于特殊功能的需要,微孔或孔隙是各类型FGM中的常见缺陷.从细观结构上看,多孔FGM中的孔隙包含了单一组份内的材料孔隙和组份微粒间的结构间隙,这些孔隙将对FGM的力学性能,尤其是在湿热环境下的力学行为产生影响.本文考虑FGM中的两类细观孔隙(材料孔隙和结构孔隙),提出了令各类孔隙依赖于各自组份变化,再线性叠加得到的整体孔隙计算式.考虑组份材料和孔隙填充物(液相水和水蒸气)性质的温度相关性,建立了湿热相关FGM材料模型.针对厚度沿径向变化的旋转圆板结构,应用该FGM材料模型,推导了圆板的非线性稳态湿热控制方程及考虑湿热弹性本构的位移控制方程,采用微分求积法(differential quadrature method,DQM),获得了圆板的湿热场、位移场和应力分布.在数值算例中,利用退化模型的解析解对本文的数值计算方法进行了验证,继而通过改变各关键参数,讨论了两类孔隙率、梯度指数和圆板厚度变化对含孔隙FGM变厚度旋转圆板湿热力学响应的影响规律.

关键词：湿热环境孔隙率功能梯度变厚度圆板微分求积法

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