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Nucleophilic Radicals as hydrogen Atom Abstractors in C(sp3)-h Functionalization Reactions

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Chinese Journal of Chemistry 2023年第5期41卷 544-547页

作者： Tao li Jian li haohua huo State Key laboratory of Physical Chemistry of Solid Surfaces Key Laboratory of Chemical Biology of Fujian ProvinceCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

hydrogen atom transfer(hAT)is an elementary mechanistic step in organic *** photoredox-catalyzed hAT has transformed organic synthesis by enabling the activation and subsequent cross-coupling of traditionally inert ye... 详细信息

关键词： Radicals hydrogen atom transfer(hAT) C(sp^(3))-h functionalization Polarity matching Photocatalysis

The Cauchy Problem for the Generalized Korteweg-de Vries-Benjamin-Ono Equation with low Regularity Data

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Acta Mathematica Sinica,English Series 2005年第5期21卷 1191-1196页

作者： Zhao hui huo Bo ling GUO Department of Mathematics School of Sciences Beijing University of Aeronautics and Astronautics Beijing 100083 P. R. China Institute of Applied Physics and Computational Mathematics P. O. Box 8009 Beijing 100088 P. R. China

The Cauchy problem of the generalized Korteweg-de Vries-Benjamin-Ono equation is considered, and low regularity and limit behavior of the solutions are obtained. For k = 1, local well- posedness is obtained for data in h^s（R）（s 〉 -3/4）. For k = 2, local result for data in h^S（R）（s 〉1/4） is obtained. For k = 3, local result for data in h^S（R）（s 〉 -1/6） is obtained. Moreover, the solutions of generalized Korteweg-de Vries-Benjamin-Ono equation converge to the solutions of KdV equation if the term of Benjamin-Ono equation tends to zero.

关键词： Generalized Korteweg-de Vries-Benjamin-Ono equation The Fourier restriction norm,low regularity solution limit behavior

Akt Gene Therapy Enhances Angiogenesis in Ischemic hind limb

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Chemical Research in Chinese Universities 2010年第3期26卷 409-414页

作者： huo Xin ZhANG Qiang lIU Ying Department of Geriatrics First Affiliated Hospital China Medical University Shenyang 110001 P. R. China

Both bone marrow-derived mesenchymal stem cells（MSCs） therapy and gene therapy have been applied to animal studies and clinical trials. The goal of this study was to compare the effects of three types of MSCs transplantation. In the first part of the study, MSCs were transduced with the pEGFP-C1 and transfected with the pEGFP-C1/Akt in a model of bilateral hind limb ischemia in rats. Following gene transduction, the production of Akt and VEGF protein was more in the culture media of GFP-Akt/MSCs group than that in those of the GFP/MSCs group In the second part of the study, Sprague-Dawley rats（n=10/group） underwent surgery to create bilateral hind limb ischemia and were randomized into two groups consisting of a GFP/Akt-MSCs group（MSCs suspension, 1×10^7 MSCs/100 μl transfected pEGFP-C1/Akt） and a GFP-MSCs group（MSCs suspension, 1 × 10^7 MSCs/100 μl）. These PEGFP-C1/Akt and PEGFP-C 1 transfected MSCs suspensions were slowly infused into the adductor muscles of the rat＇s left hind limb, while the rat＇s right hind limb in the control group received an equal volume of PBS. Endpoints includes angiographic analysis, evaluation of capillary density, immunohistochemistry for von Willebrand factor （vWF）, immunodetection of Akt and VEGF protein, RT-PCR of VEGF and Akt mRNA levels in vitro and in vivo. Our data indicate that the tissue perfusion can improve capillary density and the mature of vasculature in the GFP-Akt/MSCs group compared to that in the GFP-MSCs group or control group in the rat model of bilateral hind limb ischemia. Transplantation of MSCs transfected with Akt gene may become the future therapy for hind limb ischemia.

关键词： Bone mesenchymal stem cell pEGFP-C1/Akt hindlimb Ischemia Angiogenesis

On the dynamics and control of the Sun-Earth l_(2) tetrahedral formation

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Astrodynamics 2021年第4期5卷 331-346页

作者： Yijun lian Zhuoxi huo Yu Cheng College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China Qian Xuesen laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China School of Automation Beijing University of Posts and TelecommunicationsBeijing 100876China

The dynamics and control of a tetrahedral spacecraft formation flying in the Sun-Earth l2 region is initiatively studied,based on the circular restricted three-body problem(CR3BP).Driven by the science goal of identifying extra-solar terrestrial planets and the requirement of imaging optics,a conceptional four-spacecraft triangular pyramid configuration has been proposed for the Multiple-spacecraft Exoplanet Aperture sYnthetic INterferometer(MEAYIN)project,China’s first mid-infrared interferometric imaging *** it looked promising from an optical perspective,the configuration has not been verified *** formation is required to be virtually“rigid”,because its mutual distances and inertial pointing direction must be maintained with very high accuracy during each *** this study,the spatial geometrical relationship between the four spacecraft was established by introducing the parameters of lengths,angles,and a reference *** first contribution is that a compact set of normalized factors and critical time indices are defined,which can provide a complete description of the drift of the shape and pointing direction of the configuration,caused by the unstable dynamical *** design variables are isolated and analyzed,and their individual impacts on the uncontrolled evolution of the formation are *** main results obtained reveal that the dimensions of the rigid configuration allow a free drift for a time period on the order of tens of hours,while the inertial pointing direction will be lost within merely tens of ***,to form a rigid configuration,the control challenge lies in the fact that control efforts are frequently required for each spacecraft in the fleet,owing to the diverging *** a second contribution,a simple and feasible control algorithm is proposed to maintain the rigidity of the formation *** results indicate that the associated energy cost is merely 0.05 m/s per obser

关键词： tetrahedron configuration Multiple-spacecraft Exoplanet Aperture sYnthetic INterferometer(MEAYIN) formation flying dynamics and control interferometry libration point orbit

Adaptive Integral-type Sliding Mode Control for Spacecraft Attitude Maneuvering Under Actuator Stuck Failures

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Chinese Journal of Aeronautics 2011年第1期24卷 32-45页

作者： hU Qinglei ZhANG Youmin huo Xing XIAO Bing Department of Control Science and Engineering Harbin Institute of Technology Harbin 150001 China Department of Mechanical and Industrial Engineering Concordia University Montreal H3G 2W1 Canada

A fault tolerant control （FTC） design technique against actuator stuck faults is investigated using integral-type sliding mode control （ISMC） with application to spacecraft attitude maneuvering control system. The principle of the proposed FTC scheme is to design an integral-type sliding mode attitude controller using on-line parameter adaptive updating law to compensate for the effects of stuck actuators. This adaptive law also provides both the estimates of the system parameters and external disturbances such that a prior knowledge of the spacecraft inertia or boundedness of disturbances is not required. Moreover, by including the integral feedback term, the designed controller can not only tolerate actuator stuck faults, but also compensate the disturbances with constant components. For the synthesis of controller, the fault time, patterns and values are unknown in advance, as motivated from a practical spacecraft control application. Complete stability and performance analysis are presented and illustrative simulation results of application to a spacecraft show that high precise attitude control with zero steady-error is successfully achieved using various scenarios of stuck failures in actuators.

关键词： integral sliding mode control attitude maneuvering stuck failure adaptive control spacecraft

The Cauchy Problem for the Fifth Order Shallow Water Equation

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Acta Mathematicae Applicatae Sinica 2005年第3期21卷 441-454页

作者： Zhao-hui huo Department of mathematics School of Sciences Beijing University of Aeronautics and Astronautics Beijing100083China

The local well-posedness of the Cauchy problem for the fifth order shallow water equation δtu＋αδx^5u＋βδx^3u＋rδxu＋μuδru=0,x,t∈R, is established for low regularity data in Sobolev spaces h^s（s≥-3/8） by the Fourier restriction norm method. Moreover, the global well-posedness for l^2 data follows from the local well-posedness and the conserved quantity. For data in h^s（s〉0）, the global well-posedness is also proved, where the main idea is to use the generalized bilinear estimates associated with the Fourier restriction norm method to prove that the existence time of the solution only depends on the l^2 norm of initial data.

关键词： Shallow water equation the Fourier restriction norm [k Z] multiplier bilinear estimates

Synergistic silver-mediated and palladium-catalyzed nondirected olefination of aryl C–h bond: quick access to multi-substituted aryl olefins

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Science China Chemistry 2024年第3期67卷 882-889页

作者： Jian Yao lili Shao Xiaohong huo Xiaoming Wang Shanghai Key laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 20032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

Transition metal-catalyzed olefination of aryl C-h bond is a powerful tool for the synthesis of alkenes. While the Pd-catalyzed oxidative C-h olefination of arenes, also known as Fujiwara-Moritani reaction, has been established as one of the most efficient methods, the substrates are largely limited to terminal olefins with electron-withdrawing group(s). herein, we report a synergistic silver-mediated and palladium-catalyzed non-directed C-h olefination of arenes with vinyl(pseudo)halides, which offers a complementary strategy to the typical Fujiwara-Moritani reaction. The reactions proceeded well for a variety of halogenated arenes, heteroarenes, and olefin substrates, providing an efficient access to various multi-substituted aryl olefins, including trisubstituted/tetrasubstituted olefins and several complex olefins derived from medicines or natural products. Mechanistic studies indicated a bimetallic Pd/Ag cooperation is operative in the catalysis, i.e., the reaction is initiated by aryl C-h bond cleavage via ligation with phosphine/Ag species, followed by transferring of the aryl moiety to a vinyl palladium intermediate,which is in turn formed by oxidative addition of vinyl(pseudo)halide to a Pd complex. This method enables the synthesis of a wide range of challenging multi-substituted vinyl products from simple arenes(directing-group free) in a streamlined and controllable fashion.

关键词： direct C–h olefination multi-substituted aryl alkenes bimetallic Pd/Ag cooperation C–h functionalization

Developing a Transformation-Independent and Unbiased qPCR Assay to Rapidly Evaluate the Determinants of DNA Assembly Efficiency

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Engineering 2019年第4期5卷 803-810页

作者： Xiaoyan Ma Xinxin liang Yi-Xin huo Key laboratory of Molecular Medicine and Biotherapy School of Life ScienceBeijing Institute of TechnologyBeijing 100081China UClA Institute for Technology Advancement(Suzhou) Suzhou 215123China

Synthetic biology is moving in the direction of larger and more sophisticated design,which depends heavily on the efficient assembly of genetic *** evaluation of the DNA assembly efficiency(AE)requires transformation,and the whole process requires up to 10 h and is susceptible to various *** achieve rapid and reliable determination of the AE,an alternative transformation-independent method was established using a modified quantitative polymerase chain reaction(qPCR)*** AE is represented by the proportion of the ligated fragment,which can be determined within 3 *** qPCR-based measurement was tested by the commonly used restriction ligation,Golden Gate assembly,and Gibson assembly for the assembly of two or more DNA pieces;the results correlated significantly with the AEs represented by the counting of the colony-forming units(CFUs).This method outperformed the CFU-based measurement by reducing the measuring bias and the random deviations that stem from the transformation *** method was then employed to investigate the effects of terminal secondary structures on DNA *** results revealed the major effects of the overall properties of the overlap sequence and the negative effects of hairpin structures on the AE,which are relevant for all assembly techniques that rely on homologous annealing of the terminal *** qPCR-based approach presented here should facilitate the development of DNA assembly techniques and the diagnosis of inefficient assemblies.

关键词： Assembly efficiency DNA assembly qPCR Secondary structure Transformation

On Nearly SS-Embedded Subgroups of Finite Groups

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Chinese Annals of Mathematics,Series B 2014年第6期35卷 885-894页

作者： lijun huo Wenbin GUO Alexander A.MAKhNEV Department of Mathematics University of Science and Technology of China Institute of Mathematics and Mechanics of UB RAS Ekaterinburg 620219Russia

Abstract let h be a subgroup of a finite group G. h is nearly SS-embedded in G if there exists an S-quasinormal subgroup K of G, such that hK is S-quasinormal in G and h∩ K≤hseG, where hseG is the subgroup of h, generated by all those subgroups of h which are S-quasinormally embedded in G. In this paper, the authors investigate the influence of nearly SS-embedded subgroups on the structure of finite groups.

关键词： S-quasinormal subgroup Nearly SS-embedded subgroup Sylow sub-group p-nilpotent group Supersolvable group