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n-Type Semiconductive Polymers Based on Pyrene-1,5,6,10-Tetracarboxyl diimide

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Chinese Journal of Polymer Science 2023年第10期41卷 1584-1590页

作者： Xu-Dong Bai Zi-di yu Yao Li Tian-yu Zhang di Zhang Jie-yu Wang Jian Pei Da-Hui Zhao Beijing National Laboratory for Molecular Sciences Centre of Soft Matter Science and Engineering and Key Lab of Polymer Chemistry&Physics of Ministry of EducationCollege of ChemistryPeking UniversityBeijing100871China

Donor-acceptor(D-A)conjugated polymers comprising electron-deficient aromatic dicarboximide units represent an important type of organic semiconductors,especially for electron transporting ***-1,5,6,10-tetracarboxyl diimide(Pydi),a new PAH dicarboximide molecule recently reported by us,provides a fine balance between the electron-stabilizing ability andπ-stacking tendency,as compared to the naphthalenediimide(Ndi)and perylenediimide(Pdi)*** this study,using thienylene-vinylene-thienylene(TVT)and biselenophene(BS)as the electron donating comonomer,along with Pydi as the acceptor moiety,we develop two new D-A type conjugated polymers,which exhibit impressive electron-transporting ***,in the solution-processed OFET devices,electron mobility of 0.18 and 0.20 cm^(2)·V^(−1)·s^(−1) are achieved with these polymers,*** findings further prove the optimal potential of Pydi for application as an electron-acceptor building block in the development of polymeric n-type semiconductors among all various high-performance functional D-A polymers.

关键词： Pyrenedimide Conjugated polymers Donor-acceptor Organic electronics

Metal-ion Interactions with Sugars:Crystal Structure of Bis(4-dehydro-L-arabinose) Calcium Methanol Bishydrate

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Chinese Journal of Structural Chemistry 2015年第5期34卷 764-770页

作者： HU Biao yu di HUANG Kai yu Shu-Juan College of Light Industry and Food Science South China University of Technology

The crystal structure of the metal-organic frame Ca（C5H9O5）2·CH3OH·2H2O（1） has been synthesized and *** 1 belongs to a tetragonal P43212 space *** complex 1,the sugar moiety shows a beta-L configuration of pyranose *** calcium（Ⅱ） is eight-coordinated,binding to four such sugar moieties,via O（1）,O（2） of two molecules and O（3）,O（4） of the other two,with the 4-hydroxy group being *** water and methanol molecules are not coordinated to the calcium ion.

关键词： metal-organic framework Ca-L-arabinose complex crystal structure

distributed stereoscopic rotating formation control of networks of second-order agents

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Journal of Systems Engineering and Electronics 2013年第3期24卷 480-487页

作者： Li Song Qinghe Wu di yu Yinqiu Wang Key Laboratory of Complex System Intelligent Control and Decision(Ministry of Education) School of AutomationBeijing Institute of Technology School of Automation Beijing Institute of Technology

distributed stereoscopic rotating formation control of networks of second-order agents is investigated. A distributed control protocol is proposed to enable all agents to form a stereoscopic formation and surround a common axis. Due to the existence of the rotating mode, the desired relative position between every two agents is time-varying, and a Lyapunov-based approach is employed to solve the rotating formation control problem. Finally, simulation results are provided to illustrate the effectiveness of the theoretical results.

关键词： multi-agent system collective motion stereoscopic rotating formation control.

Consensus algorithm for multiple quadrotor systems under fixed and switching topologies

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Journal of Systems Engineering and Electronics 2013年第5期24卷 818-827页

作者： Yinqiu Wang Qinghe Wu Yao Wang di yu School of Automation Beijing Institute of Technology

The distributed leadless consensus problem for multiple quadrotor systems under fixed and switching topologies is investigated. The objective is to design protocols achieving consensus for networked quadrotors＇ positions and attitudes. Because the model of a quadrotor is a strong high-order nonlinear coupling system, the approach of feedback linearization is employed to transform the model into a group of four linear subsystems among which there is no coupling. Then, a consensus algorithm is proposed which consists of a local feedback controller and interactions from the finite neighbors under fixed undirected topologies. Especially, the problem of choosing the parameters in the consensus algo-rithm is also addressed, enlightened by the results of the robust control theory. Furthermore, it is proved that the proposed algo-rithm also guarantees the consensus under undirected switching topologies. Simulation results show the effectiveness of the pro- posed algorithm.

关键词： consensus multiple quadrotor system high-order nonlinear system feedback linearization switching topology.

Inhibition of LY294002 in retinal neovascularization via down-regulation the PI3K/AKT-VEGF pathway in vivo and in vitro

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International Journal of Ophthalmology(English edition) 2018年第8期11卷 1284-1289页

作者： yu di Xiao-Long Chen Department of Ophthalmology Shengjing Affiliated HospitalChina Medical University

AIM： To investigate the effects of the phosphatidylinositol 3-kinase（PI3 K） inhibitor LY294002 on retinal neovascularization（RNV） in the oxygen-induced retinopathy（OIR） mouse model and human umbilical vein endothelial cells（HUVECs）.METHODS： C57 BL/6 J mice were randomly divided into normoxia-control, OIR-control and LY294002 treatment groups. LY294002 or phosphate-buffered solution was intraperitoneally injected daily into mouse pups from P6 to P9 in LY294002 treatment group or OIR-control group. Morphological and pathological changes in RNV, as well as expression levels of PI3 K, serine-threonine kinase（AKT） and vascular endothelial growth factor（VEGF） were observed. HUVECs treating with LY294002 were exposed to hypoxia; the expression of PI3 K, AKT and VEGF were examined by Western blot and RT-PCR ***： Compared with the OIR-control group, LY294002 significantly inhibit RNV. Adenosine diphosphatase（ADPase） staining and hematoxylin and eosin staining indicated that the clock hour scores of neovascularization and the nuclei of pre-retinal neovascular cells in the LY294002 treatment group were clearly less than those in the OIR-control group（1.41±0.52 vs 6.20±1.21; 10.50±1.58 vs 22.25±1.82, both P〈0.05）. Intravitreal injection of LY294002（in the LY294002 treatment group） markedly decreased PI3 K/AKT-VEGF expression compared with the OIR-control group by immunohistochemistry, Western blotting and RT-PCR（all P〈0.05）. In HUVECs treated with hypoxia, expression of PI3 K, AKT and VEGF were downregulated in the hypoxia-LY294002 group（all P〈0.05）.CONCLUSION： The PI3 K inhibitor LY294002 can inhibit RNV by downregulating PI3 K, AKT, and VEGF expression in vivo and in vitro. LY294002 may provide an effective method for preventing retinopathy of prematurity（ROP）.

关键词： vascular endothelial growth factor phospha-tidylinositol 3-kinase LY294002 retinopathy of prematurity retinal neovascularization

Novel Concise Synthesis of （-）-Clausenamide1

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Chinese Journal of Chemistry 2013年第3期31卷 344-348页

作者： di Liu Xiaoming yu Liang Huang State Key Laboratory of Bioactive Substance and Function of Natural Medicine Beijing Key Laboratory of ActiveSubstance Discovery and Drugability Evaluation Institute of Materia Medica Chinese Academy of Medical Sci-ences & Peking Union Medical College Beijing 10050 China

A six-step synthesis of （-）-clausenamide is described. Optically pure （R,E）-1,3-diphenylallylic alcohol was ac-etylated and then subjected to an Ireland-Claisen rearrangement, giving the γ,δ-unsaturated acid, which underwent a substrate-induced stereoselective bromolactonization to afford the expected all-equatorial substituted bromo-δ-lac-one. An unusual chemo-selective aminolysis of the lactone resulted in the formation of a γ,δ-epoxy-amide in stereospecific manner. Base-promoted cyclization of this intermediate and the subsequent Davis oxidation furnished the synthesis, delivering the final product in 〉99% ee and up to 34% overall yield.

关键词： (-)-clausenamide diastereoselective synthesis Ireland-Claisen rearrangement diastereoselectivebromo|actonization bromo-c^-lactone aminolysis

Efficacy of intravitreal captopril on oxygen-induced retinopathy in mice

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International Journal of Ophthalmology(English edition) 2011年第4期4卷 361-364页

作者： yu di, Xiao-Long Chen Department of Ophthalmology Shengjing Hospital of China Medical University Shenyang 110004 Liaoning Province China Graduate School of China Medical University Shenyang 110001 Liaoning Province China

AIM: To study the inhibitory effect of intravitreal captopril on oxygen-induced retinopathy (OIR) in mice. METHODS: Eighty postnatal day (P)7 C57BL/63 mice were randomly divided into treated group and control group with forty mice in each group. The mice were exposed to 75% 2% oxygen for 5 days (P7-P11) and then returned to room air for 5 days (P12-P17) to induce retinal neovascularization (RNV). Beginning on P12, the mice in treated group received daily intravitreal injections of captopril(3.0mL/kg), while those in control group received daily intravitreal injections of phosphate-buffered saline (PBS) (3.0mL/kg) through P17. After anesthetized at P17, one eye was chosen randomly as experimental eye and were enucleated. RNV was examined by Adenosine diphosphate-ase (ADPase) stained retina flat-mounts and was quantitated histologically by counting the neovascular endothelial cell nuclei anterior to inner limiting membrane (ILM). The expressions of matrix metalloproteinase-2 (MMP-2) and vascular endothelial growth factor (VEGF) were measured by immunohistochemical method. RESULTS: Comparing with control group, more regular distributions, better branch and reduced density of RNV were observed in eyes of treated group. The number of neovascular cell nuclei was less in treated group than that in control group ( t =6.135, P dicate that captopril can significantly inhibit RNV in OIR mice.

关键词： retinal neovascularization oxygen-induced retinopathy captopril intravitreal injection

Effects of LY294002 on the function of retinal endothelial cell in vitro

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International Journal of Ophthalmology(English edition) 2018年第9期11卷 1447-1450页

作者： yu di Xiao-Long Chen Department of Ophthalmology Shengjing Hospital of China Medical University

AIM： To study the effects of LY294002 [phosphatidylinositol 3-kinase（PI3K） inhibitor] on the function and mechanisms of retinal endothelial cells（RECs） in ***： RECs were randomly divided into control group and LY294002 treatment group. RECs in the control group were placed the incubator for hypoxic exposure in vitro. RECs in the LY294002 treatment group were pretreated with LY294002（40 μmol/L） under hypoxic condition. The expression of matrix metalloproteinase（MMP）-2, MMP-9, vascular endothelial growth factor（VEGF）, and apoptosis and proliferation of RECs were evaluated with Western blot, real-time reverse transcription-polymerase chain reaction（RT-PCR）, and flow cytometric analysis, ***： Compared with the control group, treating the RECs with LY294002 was able to remarkably inhibit cell proliferation rates（t_（1d）=2.13, t_（2d）=2.65, t_（3d）=2.36, t_（4d）=2.06, all P〈0.05）. Flow cytometric analysis indicated that a moderate increase in apoptosis in the LY294002 treatment group compared to the control group（t=2.51, P〈0.05）. The expression of MMP-2, MMP-9 and VEGF were downregulated in the LY294002 treatment group by Western blot and real-time RT-PCR（all P〈0.05）.CONCLUSION： LY294002 regulates the function of RECs by reducing the expression of MMP-2, MMP-9, and VEGF in vitro. LY294002 may provide an effective method for preventing pathological angiogenesis.

关键词： LY294002 phosphatidylinositol 3-kinase retinal endothelial cell angiogenesis

Research progress on preparation of cerium-based oxide catalysts with specific morphology and their application for purification of diesel engine exhaust

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Journal of Rare Earths 2024年第7期42卷 1187-1216,I0001页

作者： Chunlei Zhang Siyu Gao di yu Shengran Zhou Lanyi Wang Xuehua yu Zhen Zhao Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang110034China State Key Laboratory of Heavy Oil Processing China University of PetroleumBejing102249China

The elimination of pollutants from diesel exhaust has received widespread research attention as they cause serious air pollution and pose a threat to human *** post-treatment technology is one of the most effective and universal technologies to treat diesel exhaust *** design and development of efficient and low-cost catalysts is the key factor to realize the wide application of catalytic post-treatment ***(Ce)-based oxides with specific morphologies are widely used to eliminate pollutants in diesel vehicle exhaust due to their unique physical and chemical properties,such as high catalytic activity,low cost and *** this review,the preparation methods of Cebased oxide materials with specific morphologies,such as nanoparticles,nanocubes,nanorods,nanofibers,and multi-stage pores,are introduced in detail,and the research progress on using these catalysts for the removal of carbon monoxide,hydrocarbons,soot particles,nitrogen oxides,and other pollutants from diesel exhaust is reviewed in ***,the unresolved issues associated with using Ce-based oxide catalysts with a specific morphology to catalytically remove pollutants from diesel exhaust are highlighted,and future application prospects and development directions are discussed.

关键词： Ce-based oxide catalysts dies elexhaust pollutants Specific morphology Catalytic purification Rare earths