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Asymmetric Synthesis of Novel Axially Chiral 2,2＇-Bipyridine N,N＇-Dioxides Bearing α-Amino Acid Residues and Their Applications in Enantioselective Allylation of Aromatic Aldehydes with Allyltrichlorosilane

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Chinese Journal of Chemistry 2013年第4期31卷 485-493页

作者： hongwu zhao Yuanyuan Yue Hailong Li Zhihui Sheng zhao Yang Wei Meng College of Life Science and Bio-engineering Beijing University of Technology Beijing 100124 China

A series of novel axially chiral 2,2＇-bipyridine N,N＇-dioxides bearing C1 or C2-symmetry have been synthesized by the use of enantiopure a-amino acids as chiral sources. The absolute stereochemistry of the axial chirality of these organocatalysts has been clearly assigned by means of CD measurements together with literature protocols. The reactivities and enantioselectivities of these organocatalysts have been examined in the reactions of aromatic aldehydes with allyltrichlorosilane, thus providing the desired products with moderate yields and enantioselectivies.

关键词： 2,2'-bipyridine N,N'-dioxide organocatalyst asymmetric catalysis enantioselective allylation allyl-trichlorosilane

Organocatalytic Stereoselective Synthesis of 3-Alkyl-3-hydroxy-2-oxindoles Catalyzed by Novel Water-compatible Axially Unfixed Biaryl-based Bifunctional Organocatalysts

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Chinese Journal of Chemistry 2014年第5期32卷 417-428页

作者： hongwu zhao Wei Meng zhao Yang Ting Tian Zhihui Sheng Hailong Li Xiuqing Song Yutong Zhang Sen Yang Bo Li College of Life Science and Bio-engineering Beijing University of TechnologyBeijing 100124China

In this work,six novel axially unfixed biaryl-based water-compatible bifunctional organocatalysts were de-signed and synthesized for the organocatalytic access to a variety of 3-alkyl-3-hydroxy-2-oxindole derivatives via aldol reactions in *** by 5a,the direct aldol reactions of isatins with enolisable ketones under-went readily in water,furnishing the structurally diverse 3-alkyl-3-hydroxy-2-oxindoles in various stereoselectivi-ties(up to>99%dr and>99%ee).Moreover,a plausible transition state of the conducted aldol reactions was hy-pothesized to shed light on the observed stereoselectivities of the obtained 3-alkyl-3-hydroxy-2-oxindoles.

关键词： organocatalysis 3-alkyl-3-hydroxy-2-oxindole water-compatibility bifunctionality

Spin current transmission in Co1-xTbx films

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Chinese Physics B 2022年第2期31卷 144-148页

作者： Li Wang Yangtao Su Yang Meng Haibin Shi Xinyu Cao hongwu zhao Beijing National Laboratory for Condensed Matter Physics Instiute of PhysicsChinese Academy of SciencesBeiing 100190China School of Physical Sciences.University of Chinese Academy of Sciences Beijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

We investigate the spin to charge conversion phenomena in Y_(3)Fe_(5)O_(12)/Pt/Co_(1-x)Tb_(x)/Pt multilayers by both the spin pumping and spin Seebeck *** find that the spin transport efficiency is irrelevant to magnetization states of the perpendicular magnetized Co;Tb;films,which can be attributed to the symmetry requirement of the inverse transverse spin Hall ***,the spin transmission efficiency is significantly affected by the film concentration,revealing the dominant role of extrinsic impurity scattering caused by Tb *** present results provide further guidance for enhancing the spin transport efficiency and developing spintronic devices.

关键词： spin to charge conversion perpendicular magnetized ferrimagnetic alloy inverse spin Hall effect

Inverse spin Hall effect in ITO/YIG exited by spin pumping and spin Seebeck experiments

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Chinese Physics B 2019年第1期28卷 550-554页

作者： Kejian Zhu Weijian Lin Yangtao Su Haibin Shi Yang Meng hongwu zhao Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences School of Physical Sciences University of Chinese Academy of Sciences Songshan Lake Materials Laboratory

Spin currents, which are excited in indium tin oxide(ITO)/yttrium iron garnet(YIG) by the methods of spin pumping and spin Seebeck effect, are investigated through the inverse spin Hall effect(ISHE). It is demonstrated that the ISHE voltage can be generated in ITO by spin pumping under both in-plane and out-of-plane magnetization ***, it is observed that the enhancement of spin Hall angle and interfacial spin mixing conductance can be achieved by an appropriate annealing process. However, the ISHE voltage is hardly seen in the presence of a longitudinal temperature gradient. The absence of the longitudinal spin Seebeck effect can be ascribed to the almost equal thermal conductivity of ITO and YIG and specific interface structure, or to the large negative temperature dependent spin mixing conductance.

关键词： spin pumping spin Seebeck effect inverse spin Hall effect

Low-dose X-ray induced long afterglow NIR luminescence from Cr3+ doped Zn1-xCdxGa2O4 spinel solid solutions

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Journal of Rare Earths 2025年第2期43卷 246-252页

作者： Tingting zhao Wenzhi Sun Shuya Wang Wei Meng Chunqing Fu Xiaoyan Fu hongwu Zhang School of Chemistry and Material Sciences Ludong University College of Materials Science and Engineering Xiamen University of Technology

The low-dose X-ray induced long afterglow near infrared（NIR） luminescence from Cr3+doped Zn1-xCdxGa2O4spinel solid solutions was *** structure analysis shows the good formation of Zn1-xCdxGa2O4spinel solid solutions,which possesses a cubic spinel structure with Fd3m space *** formation of Zn1-xCdxGa2O4spinel solid solutions induces the obvious increase of long afterglow near infrared luminescence excited by low-dose X-ray,When the content of doped Cd2+reaches 0.1,the low-dose X-ray induced long afterglow NIR luminescence is the *** importantly,only 5 s Xray irradiation can induce more than 6 h NIR afterglow emission,of which the afterglow luminescent intensity is still 5 times stronger than the background intensity after 6 *** thermoluminescent results show that under the 5 s exposure of X-ray,the trap density of Zn0.9Cd0.1Ga2O4:Cr3+is much higher than that of ZnGa2O4:Cr3+.The replacement of Cd2+ions with large radius at Zn2+sites causes the increase of de fects and dislocations,which results in the obvious increase of trap co *** the addition of high-z number elements Cd2+would enhance the X-ray absorption of the solid solutions,which thus can be easily excited by low-dose ***0.9Cd0.1Ga2O4:1%Cr3+solid solution is a potential candidate of lowdose X-ray induced long afterglow luminescent materials.

关键词： Phosphors Rare earths Solid solutions X-ray induced long afterglow luminescence Zn1–xCdxGa2O4:1%Cr3+

The design and experimental investigation of control system for acoustic liner with adjustable impedance

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Chinese Journal of Acoustics 1999年第1期18卷 70-80页

作者： zhao hongwu SUN Xiaofeng(Beijing University of Aeronautics and Astronautics Beijing 100083)

A kind of new acoustic liner with adjustable impedance has been proposed. At the same time, a set of control system has been designed for this kind of liner. Many experimental results have been obtained based on this control system. In fact, the present investigation shows the possibi1ity of active control of sound absorption coefficient or impedance of a liner according to external sound source condition by means of a standing wave tube. The experimental results show that the sound absorption coefficient of the liner can keep optimal under any sound source condition by controlling the cavity depth and the flow rate through the perforated plate of the liner. In addition, hoth the resistance and the reactance of the liner can also be controlled independently corresponding to any given condition. which is necessary to control unsteady How in turbomachinery.

关键词： The design and experimental investigation of control system for acoustic liner with adjustable impedance

Analysis of Data on Xanthan Fermentation in Stationary Phase Using Black Box and Metabolic Network Models

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Chinese Journal of Chemical Engineering 1999年第4期7卷 321-325页

作者：马红武赵学明唐寅杰 Tianjin Univ Sch Chem Engn & Technol Tianjin 300072 Peoples R China

The xanthan fermentation data in the stationary phase was analyzed using the black box and the metabolic network models. The data consistency is checked through the elemental balance in the black box model. In the metabolic network model, the metabolic flux distribution in the cell is calculated using the metabolic flux analysis method, then the maintenance coefficients is calculated.

关键词： xanthan fermentation black box model metabolic flux analysis maintenance coefficients

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操作响应模型在虚拟操作训练系统中的应用

计算机工程 2006年第3期32卷 267-269页

作者：刘耀周刘延宏赵宏武军械技术研究所石家庄050000 南京军区导弹站南京210000

通过一个基于操作规程的虚拟操作训练系统研究了系统仿真流程,分析了基于产生式规则响应模型主要研究的内容,结合开放式操作行为特点,给出了操作响应模型知识描述。根据操作行为特点确定了产生式系统的操作流程控制策略,形成了系统的操... 详细信息

通过一个基于操作规程的虚拟操作训练系统研究了系统仿真流程,分析了基于产生式规则响应模型主要研究的内容,结合开放式操作行为特点,给出了操作响应模型知识描述。根据操作行为特点确定了产生式系统的操作流程控制策略,形成了系统的操作响应模型。

关键词：产生式规则虚拟操作训练响应模型操作流程控制策略

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一种新的超级节点对等网的声誉管理协议

华中科技大学学报（自然科学版） 2008年第1期36卷 44-48页

作者：金瑜顾进广赵红武古志民北京理工大学计算机科学技术学院北京100081 武汉科技大学计算机科学与技术学院湖北武汉430081

针对现有对等网中声誉管理的不足,基于预投票的声誉管理协议,提出了一个适用于超级节点对等网SP2PRep,在SP2PRep中,叶子节点预先向超级节点汇报声誉投票,声誉查询仅在超级节点层进行.给出了SP2PRep协议描述、实现的消息格式和体系结构.... 详细信息

针对现有对等网中声誉管理的不足,基于预投票的声誉管理协议,提出了一个适用于超级节点对等网SP2PRep,在SP2PRep中,叶子节点预先向超级节点汇报声誉投票,声誉查询仅在超级节点层进行.给出了SP2PRep协议描述、实现的消息格式和体系结构.分析和仿真表明:SP2PRep既满足了声誉投票的安全性需求,又能够减少网络带宽消耗、提高声誉查询效率和快速识别恶意节点.SP2PRep协议能够很好地改善超级节点P2P系统的安全状况,促进它们的应用.

关键词：对等网声誉信任超级节点安全