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A new depsidone from Usnea diffracta

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Chinese Chemical Letters 2009年第2期20卷 187-189页

作者： Huan yang Qi Yuan Peng jin yan Ping Shi Key Laboratory for Natural Medicine of Gansu Province Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

A new depsidone, diffractione A （1）, as well as six known phenolic compounds （2-7） were isolated from Usnea diffracta. Their structures were elucidated by 1D and 2D NMR spectroscopy together with HRESIMS analysis.... 详细信息

关键词： Depsidone Usneaceae Usnea diffracta Lichen Diffractione A

Emergency logistics scheduling with multiple supply-demand points based on grey interval

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Journal of Safety Science and Resilience 2022年第2期3卷 179-188页

作者： Zhiming Ding Xinrun Xu Shan Jiang jin yan yanbo Han University of Chinese Academy of Sciences Beijing100049China Institute of Software Chinese Academy of Sciences Beijing050052China Beijing Key Laboratory on Integration and Analysis of Large-scale Stream Data Beijing100124China North China University of Technology Beijing100144China

This study aimed to address the problem of post-disaster emergency material dispatching from multiple supply points to multiple demand *** large-scale natural disasters,it is very important for multiple emergency material supply points to serve as sources of materials for multiple disaster sites and to determine emergency material scheduling solutions ***,the quantity of emergency materials required at each disaster site is *** address this issue,in this study,we developed an emergency material scheduling model with multiple logistics supply points for multiple demand points based on the grey interval *** optimize the proposed multi-supply-point and multi-demand-point emergency material scheduling mode,a multi-objective optimization algorithm based on a genetic algorithm was *** results demonstrate that the multi-objective optimization method can solve the emergency logistics scheduling problem better than the particle swarm optimization multi-objective solution ***,the multi-supply point and multi-demand point emergency material dispatch model and optimization algorithm provides robust support for emergency management system decision-makers when they need to respond quickly to disaster relief activities.

关键词： Emergency logistics scheduling Multi-objective programming Disaster relief

Heteropolymolybdate as a New Reaction-controlled Phase-transfer Catalyst for Efficient Alcohol Oxidation with Hydrogen Peroxide

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Chinese Chemical Letters 2006年第6期17卷 848-850页

作者： Zhi Huan WENG jin yan WANG Xi Gao JIAN Department of Polymer Science and Materials Dalian University of TechnologyLiaoning High Performance Polymer Engineering Research Center Dalian 116012

A new catalytic process for the synthesis of aldehyde from alcohol by oxidation with H202 with high selectivity, was studied. In this system, heteropolymolybdate [C7H7N（CH3）3]3 {PO4[MoO（O2）2]4} was utilized as the reaction-controlled phase-transfer catalyst to catalyze oxidation of benzyl and aliphatic alcohols. The molar ratio of H2O2 and alcohol was 0.75, no other by-products were detected by gas chromatography, the results of oxidation reaction indicated that the catalyst has high activity and stability.

关键词： Heteropolymolybdate reaction-controlled phase-transfer alcohol oxidation.

Synthesis and Characterization of Poly(ether imide)s Containing m-Methyl and Phthalazinone Moieties

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Chinese Chemical Letters 2003年第4期14卷 331-332页

作者： jin yan WANG Shu De XIAO Xi Gao JIAN Department of Polymer Science&Materials Dalian University of TechnologyDalian 116012

Three novel poly(ether imide)s were synthesized by one-step solution polymerization from 2-(3, 4-dicarboxyl-N-phenyl)-4-(3, 4-dicarboxyl-phenoxyl-4-(2-methyl)-phenyl)-2, 3- phthal-azin-1-one dianhydride and three amin... 详细信息

关键词： Synthesis poly(ether imide)s phthalazinone dianhydride.

Dental stem cell and dental tissue regeneration

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Frontiers of Medicine 2019年第2期13卷 152-159页

作者： Qiming Zhai Zhiwei Dong Wei Wang Bei Li yan jin State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Oral Diseases Center for Tissue EngineeringFourth Military Medical UniversityXi’an 710032China Xi’an Institute of Tissue Engineering and Regenerative Medicine Xi’an 710032China Department of Oral and Maxillofacial Surgery General Hospital of Shenyang Military Area CommandShenyang 110840China State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology Department of Operative Dentistry and EndodonticsSchool of StomatologyFourth Military Medical UniversityXi’an 710032China

The teeth are highly differentiated chewing organs formed by the development of tooth germ tissue located in the jaw and consist of the enamel, dentin, cementum, pulp, and periodontal tissue. Moreover, the teeth have a complicated regulatory mechanism, special histologic origin, diverse structure, and important function in mastication, articulation, and aesthetics. These characteristics, to a certain extent, greatly complicate the research in tooth regeneration. Recently, new ideas for tooth and tissue regeneration have begun to appear with rapid developments in the theories and technologies in tissue engineering. Numerous types of stem cells have been isolated from dental tissue, such as dental pulp stem cells (DPSCs), stem cells isolated from human pulp of exfoliated deciduous teeth (SHED), periodontal ligament stem cells (PDLSCs), stem cells from apical papilla (SCAPs), and dental follicle cells (DFCs). All these cells can regenerate the tissue of tooth. This review outlines the cell types and strategies of stem cell therapy applied in tooth regeneration, in order to provide theoretical basis for clinical treatments.

关键词： stem cells pulp regeneration periodontal regeneration

Synthesis and Characterization of Poly (ether imide)s Containing Phthalazinone and Isopropyl Moieties

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Chinese Chemical Letters 2001年第7期12卷 593-594页

作者： jin yan WANG Xi Gao JIAN Shu De XIAO Department of Polymer Science&Material College of Chemical EngineeringDalian University of TechnologyDalian 116012

A novel poly(ether imide)s containing phthalazinone and isopropyl moieties derived from 2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl]-phthalazin-1-one and bisphenol-A diphthalic anhydride was synthesized by one-step solution condensation polymerization in nr-cresol. The polymer was characterized by FTIR, NMR, molecular weights, glass transition temperature, thermal degradation temperature and WAXD.

关键词： Poly (ether imide) s phthalazinone one-step solution condensation polymerization

Efficient oxidation of benzyl alcohol with heteropolytungstate as reaction-controlled phase-transfer catalyst

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Chinese Chemical Letters 2007年第8期18卷 936-938页

作者： Zhi Huan Weng jin yan Wang Xi Gao Jian Department of Polymer Science and Materials Dalian University of Technology Liaoning Research Center of High Performance Resin Engineering and Technology Dalian 116012 China

A series of heteropolytungstates has been synthesized and utilized as catalysts to catalyze oxidation of benzyl alcohol with aqueous hydrogen peroxide. The results indicated that three of these catalysts showed the properties of reaction-controlled phasetransfer catalysis, and they had excellent catalytic ability to the oxidation of benzyl alcohol. No other by-products were detected by gas chromatography. Once the hydrogen peroxide was consumed completely, the catalyst precipitated from solvent, and the results of the catalyst recycle showed that the catalyst had high stability.

关键词： Heteropolytungstate Reaction-controlled phase-transfer Benzyl alcohol Benzaldehyde Hydrogen peroxide

Research on Restoration of Murals Based on Diffusion Model and Transformer

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Computers, Materials & Continua 2024年第9期80卷 4433-4449页

作者： Yaoyao Wang Mansheng Xiao Yuqing Hu jin yan Zeyu Zhu School of Computing Hunan University of TechnologyZhuzhou412000China School of Computing Hunan Software Vocational and Technical UniversityXiangtan411100China

Due to the limitations of a priori knowledge and convolution operation,the existing image restoration techniques cannot be directly applied to the cultural relics mural restoration,in order to more accurately restore the original appearance of the cultural relics mural images,an image restoration based on the denoising diffusion probability model(Denoising Diffusion Probability Model(DDPM))and the Transformer *** process involves two steps:in the first step,the damaged mural image is firstly utilized as the condition to generate the noise image,using the time,condition and noise image patch as the inputs to the noise prediction network,capturing the global dependencies in the input sequence through the multi-attentionmechanismof the input sequence and feedforward neural network processing,and designing a long skip connection between the shallow and deep layers in the Transformer blocks between the shallow and deep layers using long skip connections to fuse the feature information of global and local outputs to maintain the overall consistency of the restoration results;In the second step,taking the noisy image as a condition to direct the diffusion model to back sample to generate the restored *** results show that the PSNR and SSIM of the proposedmethod are improved by 2%to 9%and 1%to 3.3%,respectively,which are compared to the comparison *** study proposed synthesizes the advantages of the diffusionmodel and deep learningmodel to make themural restoration results more accurate.

关键词： Transformer deep learning noise estimation network diffusion model mural restoration

Optimization of the resonant frequency servo loop technique in the resonator micro optic gyro

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第11期12卷 942-950页

作者： yang REN Zhong-he jin yan CHEN Hui-lian MA Department of Information Science ＆ Electronic Engineering Zhejiang University Hangzhou 310027 China

Proportional integrator (PI) is always adopted in the resonant frequency servo loop in a resonator micro optic gyro (RMOG). The oscillation phenomenon is observed when adjusting the loop gain surpassing a threshold. This phenomenon limits system performance on step response speed and residual error. Based on the experiment system, a simulation model was set up. Further analysis shows that the threshold gain is related to the system loop filter setting and the loop delay. The traditional PI frequency servo loop technique in the RMOG system cannot keep up with the environment's disturbance quickly enough, which leads to a large residual error. A compensating method is proposed to optimize the tracking performance, solve the oscillation problem, and speed up the system response. Simulation and experiment results show that the compensated system is superior in performance. It has less residual error in the stable state and is 10 times quicker than the uncompensated system on the step response.

关键词： Resonator micro optic gyro (RMOG) Resonance frequency servo loop Phase compensating method