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InCl_3-mediated intramolecular Friedel-Crafts-type cyclization and its application to construct the [6-7-5-6] tetracyclic scaffold of liphagal

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Science China Chemistry 2012年第1期55卷 36-42页

作者： JIANG Hao TIAN LuFeng LI ZhenTao LIU Qi LI chuangchuang YAO XinSheng yang Zhen Institute of Traditional Chinese Medicine and Natural Products Jinan UniversityGuangzhou 510632China Laboratory of Chemical Genomics Shenzhen Graduate School of Peking UniversityShenzhen 518055China and Center for Life Sciences Beijing 100871China

A unified strategy toward the construction of the [5.7.6]tricyclic skeleton of liphagal is reported,featuring InCl3-mediated intramolecular Friedel-Crafts-type cyclization.

关键词： synthesis liphagal InCl3-mediated intramolecular Friedel-Crafts annulation

q-Deformations of 3-Lie Algebras

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Algebra Colloquium 2017年第3期24卷 519-540页

作者： Ruipu Bai Lixin Lin Yan Zhang chuangchuang Kang College of Mathematics and Information Science Hebei University Baoding Hebei 071002 China

q-Deformations of 3-Lie algebras and representations of q-3-Lie algebras are discussed. A q-3-Lie algebra （A, [, ,]q, [, ,]＇q, Ja）, where q ∈ F and q ≠ 0, is a vector space A over a field F with 3-cry linear multiplications [,, ]q and [,, ]＇q from A 3 to A, and a map Jq ： A 5→ F satisfying the q-Jacobi identity Jq（x1, x2, x3, x4, x5）[x1, x2, [x3, x4, x5]q]＇q = Jq（x4, x5, x1, x2, x3）[x4, x5, [x1, x2, x3]q]＇q for all x1 ∈ A. If the multiplications satisfy that [,,]q = [,,]＇q and [,,]q is skew-symmetry, then （A, [,,]q, Jq） is called a type （I）-q-3- Lie algebra. From q-Lie algebras, group algebras and commutative associative algebras, q-3-Lie algebras and type （I）-q-3-Lie algebras are constructed. Also, the non-trivial one- dimensional central extension of q-3-Lie algebras is investigated, and new q-3-Lie algebras （DerqC[x,x-1], [, ,]q, [, ,]＇q, Jq）, and （Derδq C[x,x-1], [, ,]q, [,,]＇q, Jq） are obtained.

关键词： q-3-Lie algebra q-deformation q-Jacobi identity

InCl_3-mediated intramolecular Friedel-Crafts-type cyclization and its application to construct the [6-7-5-6] tetracyclic scaffold of liphagal

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中国科学：化学 2012年第2期42卷 200-201页

A unified strategy toward the construction of the [5.7.6]tricyclic skeleton of liphagal is reported,featuring InCl3-mediated intramolecular Friedel-Crafts-type cyclization.

关键词：分子介导脚手架应用环和 InCl3

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绥阳子弹头干椒风味品质分析

辣椒杂志 2023年第1期21卷 1-5,13页

作者：杨创创何建文张正海于海龙冯锡刚吴华茂曹亚从王立浩中国农业科学院蔬菜花卉研究所蔬菜生物育种全国重点实验室北京100081 贵州省农业科学院辣椒研究所贵阳550006

通过分析绥阳子弹头干椒的风味和营养物质,综合评价其品质,为辣椒鲜食和加工提供参考。利用气相色谱-质谱(GC-MS)和高效液相色谱(HPLC)分别测定绥阳子弹头干椒的挥发性物质、脂肪酸和辣椒素类物质的含量。结果发现,在绥阳子弹头干椒中... 详细信息

通过分析绥阳子弹头干椒的风味和营养物质,综合评价其品质,为辣椒鲜食和加工提供参考。利用气相色谱-质谱(GC-MS)和高效液相色谱(HPLC)分别测定绥阳子弹头干椒的挥发性物质、脂肪酸和辣椒素类物质的含量。结果发现,在绥阳子弹头干椒中共检测到80种挥发性物质,香橙烯、柠檬烯、4-甲基戊基3-甲基丁酸酯、乙酸乙酯为其优势挥发性物质;辣椒素类物质总量为632.5μg/g(SHU 9753);亚油酸、棕榈酸和油酸为其主要脂肪酸,不饱和脂肪酸占比较高。研究结果表明,绥阳子弹头干椒主要呈香物质是香橙烯和柠檬烯,辣椒素类物质含量高,品质佳。

关键词： GC-MS HPLC 挥发性物质辣椒素类物质脂肪酸

Research on Plant Species Identification Based on Improved Convolutional Neural Network

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Phyton-International Journal of Experimental Botany 2023年第4期92卷 1037-1058页

作者： chuangchuang Yuan Tonghai Liu Shuang Song Fangyu Gao Rui Zhang College of Computer and Information Engineering Tianjin Agricultural UniversityTianjin300392China

Plant species recognition is an important research area in image recognition in recent ***,the existing plant species recognition methods have low recognition accuracy and do not meet professional requirements in terms of recognition ***,ShuffleNetV2 was improved by combining the current hot concern mechanism,convolution kernel size adjustment,convolution tailoring,and CSP technology to improve the accuracy and reduce the amount of computation in this *** convolutional neural network models with sufficient trainable parameters were designed for differentiation *** SGD algorithm is used to optimize the training process to avoid overfitting or falling into the local *** this paper,a conventional plant image dataset TJAU10 collected by cell phones in a natural context was constructed,containing 3000 images of 10 plant species on the campus of Tianjin Agricultural ***,the improved model is compared with the baseline version of the model,which achieves better results in terms of improving accuracy and reducing the computational *** recognition accuracy tested on the TJAU10 dataset reaches up to 98.3%,and the recognition precision reaches up to 93.6%,which is 5.1%better than the original model and reduces the computational effort by about 31%compared with the original *** addition,the experimental results were evaluated using metrics such as the confusion matrix,which can meet the requirements of professionals for the accurate identification of plant species.

关键词： Deep learning convolutional neural network plant identification model improvement

Grain boundary diffusion and viscous flow governed mechanical relaxation in polycrystalline materials

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Science China Materials 2022年第5期65卷 1403-1412页

作者： chuangchuang Duan Yujie Wei State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

Grain boundary(GB) diffusion and viscous flow play dominant roles in mechanical relaxation of polycrystalline materials. The pioneering work of Zener and Kê, by accounting for relaxation in GBs by viscous shearing, predicts a single peak in the internal friction spectrum. Later investigations show the existence of two to three peaks in the internal friction spectrum when taking into account both GB diffusion and viscous flow for dissipation. In this paper, we further identify the characteristic relaxation modes in polycrystalline materials. We illustrate that competitive viscous flow and diffusion for normal stress relaxation give rise to distinct dependence of relaxation time on grain size. We construct an internal friction spectrum mapping based on the competitive deformation mechanisms including viscous flow in both normal and tangential directions and GB diffusion. The essential features of internal friction spectrum of polycrystalline materials from our analysis are consistent with available experimental observations. These findings may also be applicable to study relaxation dynamics of other material systems such as metallic glasses and porous materials.

关键词： grain boundary diffusion viscous flow internal friction spectrum polycrystalline materials Zener-Kêdissipation

Detection of composition of functional component theabrownins in Pu-erh tea by degradation method

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Food Science and Human Wellness 2022年第3期11卷 643-647页

作者： Simin Hu Xiaolei Li chuangchuang Gao Xianyu Meng Mingchao Li Yuqian Li Tianrui Xu Qian Hao Faculty of Life Science and Technology Kunming University of Science and TechnologyKunming 650500China Research Center for Analysis and Measurement Kunming University of Science and TechnologyKunming 650093China

Habitual tea consumption can reduce the risk of ASCVD morbidity and mortality and all-cause mortality in China,and long-term adherence to this habit can provide greater ***-erh tea is one of the representatives of post-fermented teas,and the polymers in Pu-erh tea have anti-cancer and anti-hyperlipidemic activities,but their chemical composition is still *** this study,the chemical composition of Pu-erh tea was investigated in detail and eight(1–8)known compounds were *** polymers in Pu-erh tea were also degraded by thiol degradation,and the fragments of quercetin and(–)-epicatechin-3-O-gallate were found in the thiol degradation products of Pu-erh tea polymers by UPLC observation and separation and *** is the first time that this fragment was obtained in Pu-erh tea polymer.

关键词： Pu-erh tea Polymer Theabrownin Thiol degradation

How Big Data and High-performance Computing Drive Brain Science

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Genomics, Proteomics & Bioinformatics 2019年第4期17卷 381-392页

作者： Shanyu Chen Zhipeng He Xinyin Han Xiaoyu He Ruilin Li Haidong Zhu Dan Zhao chuangchuang Dai Yu Zhang Zhonghua Lu Xuebin Chi Beifang Niu Computer Network Information Center Chinese Academy of Sciences University of Chinese Academy of Sciences Center of Scientific Computing Applications&Research Chinese Academy of Sciences Guizhou University School of Medicine

Brain science accelerates the study of intelligence and behavior,contributes fundamental insights into human cognition,and offers prospective treatments for brain *** with the challenges posed by imaging technologies and deep learning computational models,big data and high-performance computing(HPC)play essential roles in studying brain function,brain diseases,and large-scale brain models or *** review the driving forces behind big data and HPC methods applied to brain science,including deep learning,powerful data analysis capabilities,and computational performance solutions,each of which can be used to improve diagnostic accuracy and research *** work reinforces predictions that big data and HPC will continue to improve brain science by making ultrahigh-performance analysis possible,by improving data standardization and sharing,and by providing new neuromorphic insights.

关键词： Brain science Big data High-performance computing Brain connectomes Deep learning

地下式水电站调压室交通洞过渡过程中的风速模拟

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水利学报 2016年第4期47卷 566-574页

作者：陈闯闯杨建东郭文成武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

在考虑气体可压缩性的基础上,建立了地下式水电站调压室交通洞过渡过程中的气体运动数学模型,依据气体管道瞬变流的特征线法,提出了风速模拟的方法并编制了完整的模拟程序,通过与试验结果的对比验证了所提求解方法与模拟程序的适用性与... 详细信息

在考虑气体可压缩性的基础上,建立了地下式水电站调压室交通洞过渡过程中的气体运动数学模型,依据气体管道瞬变流的特征线法,提出了风速模拟的方法并编制了完整的模拟程序,通过与试验结果的对比验证了所提求解方法与模拟程序的适用性与合理性。然后分析了交通洞的体型(长度、断面积、倾角)对风速发展、分布及波动过程的影响,并从波动叠加的角度揭示了各因素的作用机理。结果表明:对于地下式水电站调压室交通洞在过渡过程中的风速的模拟,考虑气体可压缩性是必要的。交通洞断面的风速波动过程由低频质量波(基波)与高频弹性波(谐波)叠加而成。通气洞长度影响谐波的振幅和周期、断面积影响基波和谐波的振幅、倾角则仅影响谐波的振幅。

关键词：地下式水电站调压室交通洞过渡过程风速气体可压缩性波动叠加数值模拟