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A New Monoterpene Glucoside from the Leaves of Betula platyphylla Suk.

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Chinese Chemical Letters 2001年第4期12卷 343-344页

作者： Su Juan WANG Yue hu PEI hui ming hua Department of Natural Products Chemistry Shenyang Pharmaceutical UniversityShenyang 110015

A new monoterpene glucoside. (2E,67.)-2.6-dimethyl-8-beta -D-glucosyloxy-2,6-octadienoic acid, was isolated from the leaves of Betula platyphylla Suk. The structure was established by spectroscopic data.

关键词： Betula platyphylla Suk. monoterpene glucoside leaves.

A New Chromone Derivative from Stellera chamaejasme L

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Chinese Chemical Letters 2002年第8期13卷 738-739页

作者： Bao Min FENG Yue hu PEI hui ming hua School of Traditional Chinese Medicines Shenyang Pharmaceutical UniversityShenyang 110016

A new chromone derivative, 3-[1- (2, 4, 6-trihydroxyphenyl) 3-di-(4-hydroxyphenyl) 1-propanone-2-yl] 5,7-dihydroxy-8-di(4-hydroxyphenyl)methyl-4H-1-benzopyran-4-one, named as isomohsenone was isolated from the roots of Stellera chamaejasme L. together with known chamaechromone. Its structure was determined by the analysis of MS and NMR data, especially 2D NMR spectra.

关键词： Stellera chamaejasme L. chromone 3-[1- (2, 4, 6-trihydroxyphenyl) 3-di-(4-hydroxy- phenyl)-1-propanone-2-yl] 5, 7-dihydroxy-8-di-(4-hydroxyphenyl) methyl-4H-1- benzopyran-4- one.

A facile synthesis of terminal arylacetylenes via Sonogashira coupling reactions catalyzed by MCM-41-supported mercapto palladium(0) complex

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Chinese Chemical Letters 2008年第7期19卷 783-787页

作者： Ya Ping Xu Rong hua hu ming Zhong Cai Department of Chemistry Jiangxi Normal University Nanchang 330022 China Department of Chemistry Jinggangshan University Jian 343009 China

A variety of terminal arylacetylenes have been conveniently synthesized in good to high yields via Sonogashira coupling of aryl iodides with （trimethylsilyl）acetylene catalyzed by MCM-41-supported mercapto palladium（0） complex, followed by desilylation under mild conditions. This polymeric palladium catalyst can be reused many times without any decrease in activity.

关键词： Sonogashira coupling MCM-41-supported catalyst Mercapto palladium(0) complex Terminal arylacetylene Heterogeneouscatalysis

Gaussian-curvature-derived invariants for isometry

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Science China(Information Sciences) 2013年第9期56卷 219-230页

作者： CAO WeiGuo hu Ping LIU YuJie GONG ming LI hua Institute of Computing Technology Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences School of Computer Science and Communication Engineering China University of Petroleum

Surface deformations without tearing or stretching, preserving the intrinsic properties, are called isometries. This paper presents a new definition of Gaussian curvature moments (GCMs) by the integral of n power of Gaussian curvature. Then a series of moment invariants, called Gaussian curvature moment invariants (GCMIs), are derived via GCMs. These moment invariants share many good properties under rigid transformations and isometric non-rigid transformations, and Gaussian-Bonnet theorem is a special case of GCMI. GCMIs are invariant under isometry and scaling transformations. We construct an invariant vector as a descriptor for a surface via GCMIs, and a modified χ2 distance is defined as a measure of similarity. Finally, experiments show that it is a reliable descriptor for isometric non-rigid shape.

关键词： rigid object non-rigid object isometry scale Gaussian curvature moment moment invariant

A New Disaccharide from the Fern Macrothelypteris digophlebia

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Chinese Chemical Letters 2000年第12期11卷 1063-1064页

作者： ming hua QIU Jin ming GAO hu Qi LIU Jian Xi FU Kunming Institute of Botany The Chinese Academy of SciencesKunming 650204 Northwest Sci.&Tech.University of Agriculture and Forestry YanglingShaanxi 712100

A new disaccharide, digobiose 1, was isolated from the rhizomes of Macrothelypteris digophlebia (Bak.) Ching var. elegans (koidz.). Its structure which is very similar with that of sucrose was identified as alpha -D-g... 详细信息

关键词： Macrothelypteris digophlebia disaccharide digobiose

单层Janus Ga_(2)SSe光催化水解性质的第一性原理研究

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原子与分子物理学报 2025年第3期42卷 45-51页

作者：胡新华廖杨芳贵州省贵阳市乌当区第四中学贵阳550018 贵州师范大学物理与电子科学学院贵阳550025

光催化水解制氢为解决能源危机和环境污染问题提供了一种可行的策略.本文通过第一性原理计算,提出了单层Janus Ga_(2)SSe是一种有效的水解光催化剂.结构稳定性分析表明,单层Janus Ga_(2)SSe具有能量和动力学稳定性.电子性质表明,单层Jan... 详细信息

光催化水解制氢为解决能源危机和环境污染问题提供了一种可行的策略.本文通过第一性原理计算,提出了单层Janus Ga_(2)SSe是一种有效的水解光催化剂.结构稳定性分析表明,单层Janus Ga_(2)SSe具有能量和动力学稳定性.电子性质表明,单层Janus Ga_(2)SSe属于间接带隙半导体,有利于降低载流子的复合几率.光催化性能分析表明,单层Janus Ga_(2)SSe的能带边缘位置适合PH=0~14宽范围的光催化水解.此外,单层Janus Ga_(2)SSe具有较高的紫外光和可见光吸收、较大的内建电场、较小的载流子有效质量保证了光生载流子有效分离并快速迁移到反应活性位点参与水的氧化还原反应.研究结果为单层Janus Ga_(2)SSe的合成及其作为水解光催化剂的潜在应用提供了有价值的理论指导.

关键词： Janus材料光催化水解第一性原理

数字赋能乡村教育现代化的实然困境与优化路径

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教学与管理 2025年第1期 6-11页

作者：王倩吴家华胡恒钊安徽大学马克思主义学院合肥230601 江西农业大学马克思主义学院南昌330045

以数字赋能为发展契机,推进乡村教育现代化是中国式教育现代化的必然要求,也是乡村全面振兴的重要依托。在教育领域,数字技术蕴含着驱动乡村教育现代化发展的重要价值,能够有效扩大优质教育资源的覆盖范围、变革乡村教育形态、推动乡土... 详细信息

以数字赋能为发展契机,推进乡村教育现代化是中国式教育现代化的必然要求,也是乡村全面振兴的重要依托。在教育领域,数字技术蕴含着驱动乡村教育现代化发展的重要价值,能够有效扩大优质教育资源的覆盖范围、变革乡村教育形态、推动乡土文化的交流传播。但在推动数字赋能乡村教育现代化的实践中,面临着数字教育观念淡薄、数字基础条件不足、师生数字素养薄弱等现实阻碍,迫切需要从重塑价值观念、完善数字设施、培养师生数字素养、加强体制建设入手,为数字赋能乡村教育现代化发展注入新动力,以适应中国式教育现代化发展的新生态。

关键词：数字赋能乡村教育中国式教育现代化乡土文化

Multi-scale traffic vehicle detection based on faster ReCNN with NAS optimization and feature enrichment

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Defence Technology（防务技术） 2021年第4期17卷 1542-1554页

作者： Ji-qing Luo hu-sheng Fang Fa-ming Shao Yue Zhong Xia hua Department of Mechanical Engineering College of Field EngineeringArmy Engineering University of PLANanjing210007China

It well known that vehicle detection is an important component of the field of object ***,the environment of vehicle detection is particularly sophisticated in practical *** is comparatively difficult to detect vehicles of various scales in traffic scene images,because the vehicles partially obscured by green belts,roadblocks or other vehicles,as well as influence of some low illumination *** this paper,we present a model based on Faster ReCNN with NAS optimization and feature enrichment to realize the effective detection of multi-scale vehicle targets in traffic ***,we proposed a Retinex-based image adaptive correction algorithm(RIAC)to enhance the traffic images in the dataset to reduce the influence of shadow and illumination,and improve the image ***,in order to improve the feature expression of the backbone network,we conducted Neural Architecture Search(NAS)on the backbone network used for feature extraction of Faster ReCNN to generate the optimal cross-layer connection to extract multi-layer features more ***,we used the object Feature Enrichment that combines the multi-layer feature information and the context information of the last layer after cross-layer connection to enrich the information of vehicle targets,and improve the robustness of the model for challenging targets such as small scale and severe *** the implementation of the model,K-means clustering algorithm was used to select the suitable anchor size for our dataset to improve the convergence speed of the *** model has been trained and tested on the UN-DETRAC dataset,and the obtained results indicate that our method has art-of-state detection performance.

关键词： Neural architecture search Feature enrichment Faster R-CNN Retinex-based image adaptive correction algorithm K-means UN-DETRAC

Potato-Cabbage Double Cropping Effect on Nitrate Leaching and Resource-Use Efficiencies in an Irrigated Area

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Pedosphere 2012年第6期22卷 842-847页

作者： hu Bo FAN ming-Shou HAO Yun-Feng ZHANG Jian-hua College of Agronomy Inner Mongolia Agricultural UniversityHohhot 010019(China) Bayannur City Agriculture Science Institute Bayannur 015500(China) School of Life Sciences and State Key Laboratory of Agrobiotechnology The Chinese University of Hong KongHong Kong(China)

To reduce the nitrate leaching risk after potato （Solanum tuberosum L.） harvest and improve nitrogen fertilizer-use efficiency, a potato-cabbage double cropping system （DCS） was established at Hetao, North China, an arid area with irrigated land. A two-year field experiment demonstrated that planting early-maturing potato cultivar under plastic mulch shortened its growth period by 14 d and allowed a second crop of cabbage to scavenge the soil residual NO^--N to a depth of 160 cm, substantially reducing the risk of nitrate leaching into groundwater. The yearly total N uptake in DCS was about 110 kg ha-1 more than that in the conventional cropping system （CCS）, i.e., mono potato planting. This accounted for apparent nitrogen recovery （ANR） improvement of 16.90%-26.57% in the DCS as compared to that in the CCS for both years. As a result, the soil residual NO3-N in the 0-160 cm soil profile in the DCS was lower than that in the CCS. The solar energy-use efficiency and soil-use efficiency were also substantially increased with DCS.

关键词： apparent nitrogen recovery nitrogen uptake soil resources solar energy yield