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Ortho-(1-phenylvinyl)benzyl glycosides: Ether-type glycosyl donors for the efficient synthesis of both O-glycosides and nucleosides

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Green Synthesis and Catalysis 2020年第2期1卷 160-166页

作者： Penghua Li haiqing he Lili Xu Yingying Huang Zixi Chen Yunqin Zhang Rui Yang Guozhi Xiao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyUniversity of Chinese Academy of SciencesChinese Academy of SciencesKunming 650201China School of Chemical Science and Technology Yunnan UniversityKunming 650091China

Both O-glycosides and nucleosides are essential biomolecules with important roles in a variety of biological *** synthesis of both O-glycosides and nucleosides is a scalable and reliable method to develop new therapeutic agents and decipher their ***,the efficient synthesis of both O-glycosides and nucleosides remains one of long-standing challenges in chemical *** particular,ether-type glycosyl donors are rarely developed to achieve the efficient synthesis of both O-glycosides and nucleosides due to the stronger conditions required for breaking of the glycosidic C–O *** we report that ortho-(1-phenylvinyl)benzyl glycosides are new ether-type donors for efficient synthesis of both O-glycosides and nucleosides under mild reaction *** glycosylation method enables glycosylation with both alcoholic acceptors and nucleobases with a variety of reactive ***,the latent-active synthesis of glycans and the efficient synthesis of nucleosides antibiotics have also been successfully demonstrated in the current glycosylation protocol,thereby representing an important step toward streamlining the chemical synthesis of both O-glycosides and nucleosides.

关键词： Glycosylation O-Glycosides Nucleosides ortho-(1-Phenylvinyl)benzyl Glycosides

Study on Glulam Process

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Chinese Forestry Science and Technology 2006年第1期5卷 40-44页

作者： PENG Limin WANG haiqing he Weili Research Institute of Wood Industry Chinese Academy of Forestry Beijing 100091 P.R. China

This paper selected lumbers of Manchurian ash (Fraxinus rnandshurica), Manchurian walnut(Juglans mandshurica) and Spruce (Picea jezoensis ***) for manufacturing glulam with water-borne polymeric-isocyanate adhesive to determine process variables. The process variables that includespecific pressure, pressing time and adhesive application amount influencing the shear strength of the glulam,were investigated through the orthogonal test. The results indicated that optimum process variables forglulam manufacturing were as follows: Specific pressure of 1.5 MPa for Spruce and 2.0 MPa both forManchurian ash and Manchurian walnut, pressing time of 60 min and adhesive application amount of 250 g/m2.

关键词： glulam shear strength orthogonal test process variable

ZnBr2-Catalyzed Direct C-Glycosylation of Glycosyl Acetates with Terminal Alkynes

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ZnBr2-Catalyzed Direct C-Glycosylation of Glycosyl Acetates ...

Establishment of a hyperspectral evaluation model of ocean color satellite-measured reflectance

中国化学会第十二届全国天然有机化学学术会议

作者： haiqing he Hong-Bo Qin State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of Sciencesand Yunnan Key Laboratory of Natural Medicinal Chemistry

C-Glycosides are prevalent in biologically active natural products,such as palytoxin,spongistatin,vitexin,orientin,bergenin and halichondrin.1 Because C-glycosides are inert toward hydrolytic enzymes in vivo,they have become routine surrogates of the native O-glycosides when stability is an issue.C-alkynyl glycosides are versatile due to the presence of a triple bond that can be easily transformed into chiral carbon analogues of synthetic carbohydrates or used as building blocks of natural *** this report,a convenient,mild and high stereoselective Cglycosylation reaction has been *** acetates were coupled with terminal alkynes via ZnBr2-activation at room temperature. Their applicationswere further demonstrated by the straightforward synthesis of a key intermediate in the formal synthesis of(+)-varitriol.

关键词： C-alkynyl glycosylation zinc bromide varitriol

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Science China(Information Sciences) 2010年第9期53卷 1891-1902页

作者： MAO ZhiHua*,CheN JianYu,HUANG haiqing,he XianQiang & GONG Fang State Key Laboratory of Satellite Ocean Environment Dynamics,Second Institute of Oceanography,State Oceanic Administration,Hangzhou 310012,China 1. State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China

The accuracy of the satellite-measured reflectance is a key question for data processing and oceanographic applications.A hyperspectral satellite remote sensing reflectance evaluation model(HRSREM) was developed to evaluate the accuracy of the satellite measured *** model can compute the total reflectance at the top of the atmosphere(TOA) according to observation conditions of satellites,based on a radiative transfer model with the consideration of multiple scattering effects and atmospheric absorption *** performance of the HRSREM model was examined by Gordon’s algorithms,showing that the relative errors of the Rayleigh scattering reflectance and the aerosol scattering reflectance are less than 2%.The model can also compute the sky reflectance which can be validated by in-situ *** two sky reflectances match well with a spectral average error of 5.4%.The relative error of the total reflectance of the model,verified by sea-viewing wide field-of-view sensor(SeaWiFS) data,is about 3.5%.Therefore,the total reflectances at TOA,computed by the model,can be taken as reference values to evaluate the accuracy of satellite *** model was used to evaluate the accuracy of the hypersptral satellite(Hyperion) remote sensing *** Hyperion reflectance matches the total reflectance of HRSREM very well at visible and near-infrared bands with an average error of 7.3%,while the status of calibration coefficients at shortwave infrared bands are not stable with a large spectral average error of 63.5%.The reflectance evaluation of a moderate resolution imaging spectrometer(CMODIS) data indicated that relative errors are large,especially at near-infrared bands with relative errors more than 100%.The calibration coefficients of CMODIS,obtained from laboratory measurements,are not *** CMODIS data should be recalibrated for oceanographic *** performance of the HRSREM model is effective in evaluating satellite data and its

关键词： hyperspectral remote sensing CMODIS reflectance evaluation satellite ocean color

制度信任与乡土韧性:农民工返乡建宅行动的呈现与反思

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中国农村观察 2024年第3期 124-141页

作者：何海清华东理工大学社会与公共管理学院

与城市商品房建设形成鲜明呼应的是农村自建房的高速增长。以往研究多将返乡建宅视为农民工在城乡户籍制度区隔和城市购房经济压力下无奈返乡后的被动选择,但这并不能解释农民工“既在城购房又返乡建宅”的现象。本文研究发现:在制度的... 详细信息

与城市商品房建设形成鲜明呼应的是农村自建房的高速增长。以往研究多将返乡建宅视为农民工在城乡户籍制度区隔和城市购房经济压力下无奈返乡后的被动选择,但这并不能解释农民工“既在城购房又返乡建宅”的现象。本文研究发现:在制度的设限保护和文化的内生驱动之下,农民工返乡建宅行动是以家庭中心主义为核心做出的主动、理性和经济的决策,并在制度与文化不同程度的耦合中主要呈现“自然”建宅、“占地盘式”建宅和“情怀式”建宅三种典型样态。返乡建宅潮下人口流动的逆城镇化、住宅布局的现代化、家庭结构的主干化,以及由此带来的村庄更新,在一定程度上改善了农村“空心化”状况,强化了农民工对制度的信任感,增进了乡土韧性。但未来仍须结合乡村振兴的在地化实践,注意农民工返乡建宅现象背后的农村土地资源分配、户籍制度改革、老年友好社区建设、农村自建房安全监管、乡土文化传承与创新等问题。

关键词：返乡农民工农村自建房宅基地制度乡土文化

安土重迁:农民工返乡建宅的现实表征、类型考察及其行动逻辑

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社会发展研究 2024年第2期11卷 130-148,M0005,M0006页

作者：何海清华东理工大学社会与公共管理学院

以往对农民工返乡行为的研究较少关注返乡建宅行为,忽视了该行为蕴含的社会文化、制度要素及其与农民工返乡行为的关联性。本文以重庆市蜡烛村为例,探析了农民工返乡后的建宅行为。本研究发现:第一,在农民工的返乡建宅行为中,返乡人的... 详细信息

以往对农民工返乡行为的研究较少关注返乡建宅行为,忽视了该行为蕴含的社会文化、制度要素及其与农民工返乡行为的关联性。本文以重庆市蜡烛村为例,探析了农民工返乡后的建宅行为。本研究发现:第一,在农民工的返乡建宅行为中,返乡人的回归机制非常多样化,住宅的形态被改造,人地关系呈现出游离式状态;第二,从建宅行为的主导要素来看,可依据文化与制度的双重驱动划分为自然建宅、占地盘式建宅和情怀式建宅三种实践类型;第三,农民工返乡建宅是在既定政策背景下所做出的理性经济选择。以建宅行为为切入点理解农民工返乡,有助于我们进一步把握现代城乡流动中农村人、地、资源的联动关系,探索未来建设宜居宜业、和美乡村的有效途径。

关键词：农民工返乡农村自建房住宅重建人地关系

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一种顾及粗差的径向神经网络高程曲面拟合法

武汉大学学报（信息科学版） 2015年第4期40卷 547-551页

作者：何海清黄声享陈婷东华理工大学测绘工程学院江西南昌330013 武汉大学测绘学院湖北武汉430079 武汉大学水利水电学院湖北武汉430072

针对径向神经网络高程曲面拟合对训练样本点的粗差较为敏感的特点,从数字影像处理的原理出发,将径向神经网络拟合中含粗差训练样本点得到的格网点高程映射到灰度影像,利用影像高斯差分算法探测粗差,并采用最小二乘移动曲面法修正原始高... 详细信息

针对径向神经网络高程曲面拟合对训练样本点的粗差较为敏感的特点,从数字影像处理的原理出发,将径向神经网络拟合中含粗差训练样本点得到的格网点高程映射到灰度影像,利用影像高斯差分算法探测粗差,并采用最小二乘移动曲面法修正原始高程训练样本点中的粗差,然后再次对修正后的样本点进行径向神经网络拟合,从而实现可抵抗粗差的径向神经网络高程曲面拟合。以测量机器人采集的高程数据为例进行了实验,达到了较好的拟合结果和精度,验证了方法的鲁棒性与有效性。

关键词：径向神经网络粗差探测高斯差分移动曲面法高程曲面拟合

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深入开展学习型班组创建活动之我见

中国劳动关系学院学报 2010年第1期24卷 55-57页

作者：何海情中国远洋物流有限公司工会北京100016

深入开展学习型班组创建活动,涉及企业管理的方方面面和各个层次,需要建立长效机制不断地推动和促进。在开展学习型班组创建活动中,需要企业党政领导、管理和生产各部门高度重视和积极配合。企业工会在深入开展学习型班组建设活动中,通... 详细信息

深入开展学习型班组创建活动,涉及企业管理的方方面面和各个层次,需要建立长效机制不断地推动和促进。在开展学习型班组创建活动中,需要企业党政领导、管理和生产各部门高度重视和积极配合。企业工会在深入开展学习型班组建设活动中,通过切实履行其各项职能,充分发挥其应有的作用。

关键词：班组活动企业工会原则

城市社区公共服务虚拟集聚中供给主体的蕴含特质、关联机制及矛盾纾解

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华东理工大学学报（社会科学版） 2020年第3期35卷 134-148页

作者：何继新何海清天津城建大学经济与管理学院天津300384

"智能+"场景下的社区公共服务正处于"实体+虚拟"的快速发展阶段,政府、市场、社会、社区依托联结共治的生态网络共同体,持续促进社区公共服务虚拟集聚创新发展。通过诠释社区公共服务虚拟集聚供给主体体系蕴含的多元性、互赖性、虚拟性... 详细信息

"智能+"场景下的社区公共服务正处于"实体+虚拟"的快速发展阶段,政府、市场、社会、社区依托联结共治的生态网络共同体,持续促进社区公共服务虚拟集聚创新发展。通过诠释社区公共服务虚拟集聚供给主体体系蕴含的多元性、互赖性、虚拟性和平等性等特质,深入解读各主体在角色定位、责任体系、沟通协调和情境嵌入中的联动着力点,本文在构建社区公共服务虚拟集聚主体框架基础上,区分不同供给主体与社区公共服务虚拟集聚系统的关联机制,在虚拟集聚过程中发现供给主体间存在价值归一冲突、数据分配冲突、意识更新冲突和管理秩序冲突等矛盾关系,提出打破数据壁垒、完善网络监管机制、强化价值引导、制度配套发力等优化路径,实现提升社区公共服务虚拟集聚主体联动水平及系统集聚能力。

关键词：城市社区公共服务供给主体虚拟集聚系统关联机制