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Oxidation-induced ortho-selective C–H bond functionalization of 2-naphthylamine derivative

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Science China Chemistry 2018年第10期61卷 1274-1277页

作者： Dongchao Zhang zhiliang huang Aiwen Lei The Institute for Advanced Studies College of Chemistry and Molecular Sciences Wuhan University National Research Center for Carbohydrate Synthesis Jiangxi Normal University

Selective C–H bond functionalization has been emerged as a versatile strategy for the construction of new chemical bonds. In the past decades, the directing group(DG)-assisted C–H bond activation has been developed as one of the most efficient methods for selective C–H functionalization. Although a great progress has been made by utilizing this traditional method, developing new strategy for selective C–H bond functionalization is still highly demanded. Hence, a novel oxidation-induced C–H bond functionalization method was demonstrated in this work. By this new method, ortho-C(sp2)–H chlorination of N-substituted 2-naphthylamine was realized in a highly selective manner.

关键词： oxidation-induced C-H bond functionalization ortho-selectivity

Improved Differential Evolution with Shrinking Space Technique for Constrained Optimization

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Chinese Journal of Mechanical Engineering 2017年第3期30卷 553-565页

作者： Chunming FU Yadong XU Chao JIANG Xu HAN zhiliang huang State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University School of Mechanical Engineering Nanjing University of Science and Technology

Most of the current evolutionary algorithms for constrained optimization algorithm are low computational efficiency. In order to improve efficiency, an improved differential evolution with shrinking space technique and adaptive trade-off model, named ATMDE, is proposed to solve constrained optimization problems. The proposed ATMDE algorithm employs an improved differential evolution as the search optimizer to generate new offspring individuals into evolutionary population. For the con- straints, the adaptive trade-off model as one of the most important constraint-handling techniques is employed to select better individuals to retain into the next population, which could effectively handle multiple constraints. Then the shrinking space technique is designed to shrink the search region according to feedback information in order to improve computational efficiency without losing accuracy. The improved DE algorithm introduces three different mutant strategies to generate different offspring into evo- lutionary population. Moreover, a new mutant strategy called ＂DE/rand/best/l＂ is constructed to generate new individuals according to the feasibility proportion ofcurrent population. Finally, the effectiveness of the pro- posed method is verified by a suite of benchmark functions and practical engineering problems. This research presents a constrained evolutionary algorithm with high efficiency and accuracy for constrained optimization problems.

关键词： Constrained optimization - Differentialevolution Adaptive trade-off model Shrinking spacetechnique

A frequency domain reliability analysis method for electromagnetic problems based on univariate dimension reduction method

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Science China(Technological Sciences) 2019年第5期62卷 787-798页

作者： PING MengHao HAN Xu JIANG Chao ZHONG JianFeng XIAO XiaoYa huang zhiliang WANG ZhongHua State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan University Nanjing Research Institute of Electronics Technology

In this paper, a class of electromagnetic field frequency domain reliability problem is first defined. The frequency domain reliability refers to the probability that an electromagnetic performance indicator can meet the intended requirements within a specific frequency band, considering the uncertainty of structural parameters and frequency-variant electromagnetic *** then a frequency domain reliability analysis method based on univariate dimension reduction method is proposed, which provides an effective calculation tool for electromagnetic frequency domain reliability. In electromagnetic problems, performance indicators usually vary with frequency. The method firstly discretizes the frequency-variant performance indicator function into a series of frequency points' functions, and then transforms the frequency domain reliability problem into a series system reliability problem of discrete frequency points' functions. Secondly, the univariate dimension reduction method is introduced to solve the probability distribution functions and correlation coefficients of discrete frequency points' functions in the system. Finally, according to the above calculation results, the series system reliability can be solved to obtain the frequency domain reliability, and the cumulative distribution function of the performance indicator can also be obtained. In this study,Monte Carlo simulation is adopted to demonstrate the validity of the frequency domain reliability analysis method. Three examples are investigated to demonstrate the accuracy and efficiency of the proposed method.

关键词： electromagnetic field frequency domain reliability system reliability random process discretization univariate dimension reduction method

Diffusion Kinetics of Carbonate Hydroxyapatite (CHAP) for Adsorbing F^- Dissolved in Water

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Acta Geologica Sinica(English Edition) 2006年第2期80卷 243-248页

作者： huang zhiliang ZHANG Lianmeng LIU Yu WANG Qilin HE Qianjun CHEN Wei State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan Hubei 430070 Research Institute of Mineral Material Wuhan Institute of Technology Wuhan Hubei 430073

A systematic research was performed about diffusion kinetics of adsorbing F^- dissolved in water for carbonate hydroxyapatite （CHAP） from the natural hydroxyapatite which was modified by adulterating with CO3^2-. The result shows that the speed of F^- adsorption is controlled by membrane diffusion when F^- concentration is relatively low, which is expressed by the kinetic equation of diffusion Q=0.0005（Ci-C）（t-ti）＋0.3967, or by vacancy diffusion when F^- concentration is relatively high, which is expressed by the kinetic equation of diffusion In[C（o, t）]=8.4718-0.5048Int. Based on the feature of CHAP for adsorbing F^- dissolved in water and its special channel of the structure of CO3^3- modified hydroxyapatite, models of vacancy diffusion and membrane diffusion were established.

关键词： carbonate hydroxyapatite (CHAP) F^- ion diffusion kinetics

Precise electro-reduction of alkyl halides for radical defluorinative alkylation

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Science China Chemistry 2022年第4期65卷 762-770页

作者： Xingxiu Yan Shengchun Wang Zhao Liu Yujie Luo Pengjie Wang Wenyan Shi Xiaotian Qi zhiliang huang Aiwen Lei Institute for Advanced Studies(IAS)and College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China

Reported here is a precise electro-reduction strategy for radical defluorinative alkylation towards the synthesis of gem-difluoroalkenes from α-trifluoromethylstyrenes. According to the redox-potential difference of the radical precursors, direct or indirect electrolysis is respectively adopted to realize the precise reduction. An easy-to-handle, catalyst-and metal-free condition is developed for the reduction of alkyl radical precursors that are generally easier to be reduced than α-trifluoromethylstyrenes,while a novel electro-Ni-catalytic system is established for the electro-reduction of alkyl bromides or chlorides towards the electrochemical synthesis of gem-difluoroalkenes. The merit of this protocol is exhibited by its mild conditions, wide substrate scope, and scalable preparation. Mechanistic studies and DFT calculations proved that the coordination of α-trifluoromethylstyrenes to Ni-catalyst prevents the direct reduction of the alkene and, in turn, promotes the activation of alkyl bromide through halogen atom transfer mechanism.

关键词： electro-reductive cross-coupling gem-difluoroalkenes radical defluorinative alkylation electro/nickel catalysis C-C bonds formation

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含概率-区间混合不确定性的汽车正面碰撞可靠性优化设计

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汽车工程 2019年第5期41卷 545-549,563页

作者：王琼黄志亮湖南大学汽车车身先进设计制造国家重点实验室长沙410082 湖南城市学院机械与电气工程学院益阳413002

针对汽车正面碰撞中某些参数的概率分布函数中包含不确定的区间变量的问题,构建了一种汽车正面碰撞混合不确定可靠性优化模型,将基于误差比例选择技术的最优多项式模型引入整车碰撞分析中。由于存在区间参数,内层通过限制可靠度的区间... 详细信息

针对汽车正面碰撞中某些参数的概率分布函数中包含不确定的区间变量的问题,构建了一种汽车正面碰撞混合不确定可靠性优化模型,将基于误差比例选择技术的最优多项式模型引入整车碰撞分析中。由于存在区间参数,内层通过限制可靠度的区间下界建立概率约束,从而保证车身结构的安全性。采用了一种基于漂移向量的高效解耦算法,将嵌套优化问题转换为确定性优化和混合可靠性分析的序列迭代过程,避免了内外层嵌套寻优,实现了汽车正面碰撞可靠性优化的高效性。结果表明:优化后防撞梁、吸能盒和前纵梁的总质量减轻了2.35%,所有约束可靠度指标均得到满足,实现了保证车身轻量化要求下的车身和乘员安全性可靠性优化的目标。

关键词：正面碰撞可靠性优化概率-区间混合不确定性最优多项式模型漂移向量

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高质量发展阶段的中国经济发展道路论

中国经济问题 2021年第1期 5-16页

作者：黄志亮重庆财经学院重庆工商大学长江上游经济研究中心

中国经济发展道路及模式,在近10余年成为全世界关注的焦点,但从价值维度研究中国经济发展道路,是当今学术界的一大薄弱环节。本文以两个百年的纵深,从价值维度切入,重点论证并原创性提出了:以全体中国人民的根本利益为价值立场;以全体... 详细信息

中国经济发展道路及模式,在近10余年成为全世界关注的焦点,但从价值维度研究中国经济发展道路,是当今学术界的一大薄弱环节。本文以两个百年的纵深,从价值维度切入,重点论证并原创性提出了:以全体中国人民的根本利益为价值立场;以全体中国人民的共同富裕和自由全面发展为根本价值目的;确立三个为主(公有主体,按劳分配主体,国家宏观调控主导)和三个共存(多种经济成分,多元要素参与分配,市场决定微观资源配置)的基本经济制度,建设以高质量的实体经济国内循环为主体、国内国际双循环相互促进的现代绿色生产生活体系,建设以国家内生创新为主导、企业自主创新为主体、多元协同创新为补充的关键核心技术进步体系,建设以高质量发展的城乡融合经济体系和区域协调发展的生产力空间布局体系等等,以此四点为价值原则;以人民通过生产劳动创造幸福生活为根本价值实践主题,其核心要义是:国民幸福可持续、国办公业建和平、党揽全局谋长远、民本路线通民心。创建具备上述价值总体的目标路径同向认知体系与实践行动体系有机统一的经济发展系统,就是高质量发展阶段中国社会主义经济发展道路,亦是本文的学术创新。

关键词：高质量发展中国经济发展道路价值维度学术创新

随机载荷下压接型IGBT性能稳健性优化设计

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中国电机工程学报 2020年第23期40卷 7721-7729页

作者：黄志亮阳同光黎灿兵智慧城市能源感知与边缘计算湖南省重点实验室(湖南城市学院) 湖南省益阳市413000 电子信息与电气工程学院(上海交通大学) 上海市闵行区200240

内部应力分布是影响压接型IGBT性能的关键因素。不确定性工况导致的随机载荷进一步加剧应力失衡的影响。文中以IGBT中芯片最大应力和典型应力为性能函数,将芯片热载荷考虑为随机过程并度量其导致的质量损失,构建基于时变稳健性度量的优... 详细信息

内部应力分布是影响压接型IGBT性能的关键因素。不确定性工况导致的随机载荷进一步加剧应力失衡的影响。文中以IGBT中芯片最大应力和典型应力为性能函数,将芯片热载荷考虑为随机过程并度量其导致的质量损失,构建基于时变稳健性度量的优化模型。针对稳健性设计中嵌套优化的效率问题,提出一种解耦策略,将嵌套寻优转换成设计优化与稳健性分析的序列迭代过程。将文中方法应用于某压接型IGBT设计问题中,对比分析优化前、后应力失衡性能的质量损失。结果表明,在保证内部元件热接触稳健情况下,应力失衡性能的质量损失减少了17.3%。并且,该方法的效率远高于常规嵌套优化方法,具有良好的工程应用前景。

关键词：随机载荷压接式IGBT 稳健性优化应力失衡

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高效液相色谱法测定肉中金霉素含量

食品工业科技 2000年第5期21卷 68-70页

作者：黄志良华南农业大学食品科学系广州510640

研究了采用高效液相色谱法测定肉中金霉素含量的方法。在其它方法的基础上 ,改进了提取和纯化过程 ,优化了色谱条件。肌肉样品和肾脏样品的检测限分别为 0 .0 2μg/g、0 .0 3μg/g。回收率在 84%至 1 1 8%。该方法具有较高的回收率和灵... 详细信息

研究了采用高效液相色谱法测定肉中金霉素含量的方法。在其它方法的基础上 ,改进了提取和纯化过程 ,优化了色谱条件。肌肉样品和肾脏样品的检测限分别为 0 .0 2μg/g、0 .0 3μg/g。回收率在 84%至 1 1 8%。该方法具有较高的回收率和灵敏度。

关键词：金霉素高效液相色谱测定肉样品