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A rotary ultrasonic motor using radial bending mode of ring with nested PZT excitation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第3期13卷 189-196页

作者： Ying-xiang LIU Jun-kao LIU Wei-shan chen Xiao-hui YANG State Key Laboratory of Robotics and System Harbin Institute of Technology Horbin 150001 China

This study presents and verifies a new idea for constructing a rotary traveling wave ultrasonic motor （USM） that uses the radial bending mode of a ring. In the new design, 20 trapezoid cross section slots are cut symmetrically in the outer surface of a thick duralumin alloy ring, where 20 PZT stacks are nested. In each slot, two wedging blocks are set between the PZT stack and the two sides of the slot respectively to apply preloading on the PZT ceramics. Two radial bending modes of the stator that have a phase difference of a quarter wavelength on space are generated by using the d33 operating mode of the PZT elements, and then a flexural traveling wave is formed by the superimposing of two standing waves whose amplitudes are equal and phases are different by 90~ temporally. Two conical rotors are pressed to each end of the ring type stator by a coiled spring. The finite element method （FEM） simulation is developed to validate the feasibility of the proposed motor. The maximal speed and torque of the prototype are tested to be 126 r/rain and 0.8 N＇m, respectively.

关键词： Rotary ultrasonic motor Radial bending mode Traveling wave Wedging block clamped structure

Induction of Volatile Organic Compounds of Lycopersicon esculentum Mill. and Its Resistance to Botrytis cinerea Pers. by Burdock Oligosaccharide

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Journal of Integrative Plant Biology 2006年第5期48卷 550-557页

作者： Pei-Qing He Li Tian kao-shan chen Lin-Hua Hao Guang-You Li First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Qingdao University of Science and Technology Qingdao 266061 China Shool of Life Sciences Shandong University Jinan 250100 China

In the present study, we investigated the induction of volatile organic compounds （VOCs） of Lycoperslcon esculentum Mill. and its resistance to Botrytis cinerea Pers. by burdock oligosaccharlde. The disease severity of L. esculentum was evaluated 48 h after treatment with 0.6% burdock oligosaccharlde, followed by inoculation with a spore suspension of B. cinerea. The formation of O2＇, the activity of lipoxygenases （LOX）, peroxidase （POD）, cataiase （CAT）, and superoxide dismutase （SOD）, and the quantity and quallty of changes In VOCs were determined a period of time after treatment with 0.6% burdock ollgosaccharide. The results demonstrated that the disease index in treated plants was decreased by 42.5% compared with control 96 h after Inoculation. The production of O2＇ reached a maximum 6 h after treatment （1.36-fold compared with control）. There was an increase in LOX, POD, CAT and SOD activity in response to burdock oligosaccharide treatment and the enzymes showed different trends in the time-course of induction. At 120 h after treatment, （E）-2-hexenal was increased by 92% compared with control, whereas methyl salicylate showed a gradual Increase with induction period. Previous results had demonstrated that chitosan elicitor enhanced the production VOCs of L. esculentum and decreased plant susceptibility towards B. clnerea. Together, these findings suggest that increasing the production of VOCs in response to burrdock oligosaccharide may be an important mechanism for L. esculentumin its defense against pathogens, in addition, burrdock oligosaccharlde may act as a potent elicitor of resistance to disease in L. esculentum.

关键词： burdock oligosaccharide induction Lycopersicon esculentum resistance volatile organic compounds.

Effects of Crop Development on the Emission of Volatiles in Leaves of Lycopersicon esculentum and Its Inhibitory Activity to Botrytis cinerea and Fusarium oxysporum

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Journal of Integrative Plant Biology 2008年第1期50卷 84-91页

作者： Peng-Ying Zhang kao-shan chen Pei-Qing He Sheng-Hao Liu Wan-Feng Jiang College of Life Sciences Shandong University Jinan 250100 China Key Laboratory of Marine Bioactive Substances First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Qingdao Quafity Supervision and Inspection Center for Shopping Basket Commodity Qingdao 266003 China

Volatiles emitted from the leaves of Lycopersicon esculentum at the two-, ten-leaf and anthesis periods were collected by a gas absorbing method and analyzed by gas chromatography （GC）-mass spectrometry. In total, 33 compounds of volaUles emitted from three developmental stage plants were separated and identified, and quantitatively analyzed by the internal standard addition method. All of the samples of volatile were found to be rich in monoterpenes and sesquiterpenes.β-phellandrene and caryophyllene predominated in the volatiles of the leaves of plants at the two- and ten-leaf stages. Furthermore, （E）-2-hexenal were the dominant components in the volatiles emitted from anthesis plants. The results of volatiles analyzed show that the compositions varied depending on the developmental stages. The volatiles emitted from crushed tomato leaves of plants at the anthesis stage had the most strongly inhibitory activity against the spore germination and hyphal growth of Botrytis cinerea and Fusarium oxysporum, followed by ten- and two-leaf plants. However, the activity of volatiles, emitted from the leaves of plants at the two-leaf stage, in inhibiting F. oxysporum was greater than B. cinerea.

关键词： development inhibitroy activity Lycopersicon esculentum volatiles.

Off-on-off luminescent switching of a dye containing imidazo[4,5-f][1,10]phenanthroline

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Chinese Chemical Letters 2011年第6期22卷 647-650页

作者： Hai Guang Zhang Xu Tang Tao kao shan chen Chun Xue Yuan Shi Na Yan Min Hua Jiang College of Chemistry Science Qufu Normal UniversityQufu 273165China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China School of Life Science Shandong UniversityJinan 250100China

A new acid-base fluorescent switch containing both imidazo[4,5-f][1,10]-phenanthroline and triphenylamine groups has been *** fluorescence emissions and absorptions can be reversibiy changed through protonation/deprotonation of imidazole and amine moiety by controlling the intramolecular charge transfer（ICT） process,leading to off-on-off fluorescent molecular switching.

关键词： Fluorescence switch Imidazo[4 5-f][1 10]phenanthroline Triphenylamine Intramolecular charge transfer(ICT)

Synthesis and characterization of a new chromophor with acid/base-sensitive fluorescence emission

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Chinese Chemical Letters 2011年第9期22卷 1051-1054页

作者： Hai Guang Zhang Xu Tang Tao kao shan chen Chun Xue Yuan Shi Na Yan Min Hua Jiang College of Chemistry Science Qufu Normal University Qufu 273165 China State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China School of Life Science Shandong University Jinan 250100 China

A new two-photon absorption compound, 2-{4-[（dicyanomethylidene-5,5-dimethylcyclohexl）vinyl]phenyl}imidazo[4,5- f][1,10]phenanthroline （DDVPIP）, was synthesized and characterized. The one-photon excited fluorescence （OPEF） and two- photon excited fluorescence （TPEF） of DDVP1P are sensitive to the acid/base of the solution, which are enhanced in basic solution but weakened in acidic solution. Charge-transfer （CT） states of DDVPIP were calculated through theory methods to explain its acid/ base-sensitive fluorescent properties.

关键词： Imidazo[4,5-f][ 1,10]phenanthroline Two-photon absorption Two-photon fluorescence

Review of Computational Approaches to Optimization Problems in Inhomogeneous Rods and Plates

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Communications on Applied Mathematics and Computation 2024年第1期6卷 236-256页

作者： Weitao chen Chiu-Yen kao Department of Mathematics University of California at Riverside900 University AveRiversideCA92521USA Department of Mathematical Sciences Claremont McKenna College850 Columbia AveClaremontCA91711USA

In this paper,we review computational approaches to optimization problems of inhomogeneous rods and *** consider both the optimization of eigenvalues and the localization of *** problems are motivated by physical problems including the determination of the extremum of the fundamental vibration frequency and the localization of the vibration *** demonstrate how an iterative rearrangement approach and a gradient descent approach with projection can successfully solve these optimization problems under different boundary conditions with different densities given.

关键词： Inhomogeneous rods and plates Bi-Laplacian Optimization of eigenvalues Localization of eigenfunctions Rearrangement

A whole-net cooperative positioning method based on CDGNSS and inter-vehicle ranging

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Chinese Journal of Aeronautics 2024年第2期37卷 401-416页

作者： shan HU Hongbo ZHAO chen ZHUANG School of Electronics and Information Engineering Beihang UniversityBeijing 100191China

Relative positioning is recognized as an important issue for vehicles in urban ***-vehicle Cooperative Positioning(CP)techniques which fuse the Global Navigation Satellite System(GNSS)and inter-vehicle ranging have attracted attention in improving the performance of baseline estimation between ***,current CP methods estimate the baselines separately and ignore the interactions among the positioning information of different *** interactions are called’information coupling’.In this work,we propose a new multivehicle precise CP framework using the coupled information in the network based on the Carrier Differential GNSS(CDGNSS)and inter-vehicle *** demonstrate the benefit of the coupled information by deriving the Cramer-Rao Lower Bound(CRLB)of the float estimation in *** fully use this coupled information,we propose a Whole-Net CP(WN-CP)method which consists of the Whole-Net Extended Kalman Filter(WN-EKF)as the float estimation filter,and the Partial Baseline Fixing(PBF)as the ambiguity resolution *** WN-EKF fuses the measurements of all baselines simultaneously to improve the performance of float estimation,and the PBF strategy fixes the ambiguities of the one baseline to be estimated,instead of full ambiguity resolution,to reduce the computation load of ambiguity *** tests involving four vehicles were conducted in urban *** results show that the proposed WN-CP method can achieve better performance and meanwhile maintain a low computation load compared to the existing methods.

关键词： GNSS Cooperative positioning Baseline Ambiguity resolution Information coupling

The role of m^(6)A RNA methylation in autoimmune diseases: Novel therapeutic opportunities

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Genes & Diseases 2024年第1期11卷 252-267页

作者： Yunan shan Wei chen Yanbin Li The First Clinical Medical College Shandong University of Traditional Chinese MedicineJinanShandong 250013China Department of Neurology The First Affiliated Hospital of Shandong First Medical University&Shandong Provincial Qjanfoshan HospitalShandong Institute of NeuroimmunologyShandong Key Laboratory of Rheumatic Disease and Translational MedicineJinanShandong 250013China Department of Gastroenterology Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200233China

N6-methyladenosine m^(6)A modifications,as one of the most common forms of in-ternal RNA chemical modifications in eukaryotic cells,have gained increasing attention in recent *** m^(6)A RNA modifications exert various crucial roles in various biological pro-cesses,such as embryonic development,neurogenesis,circadian rhythms,and *** advances have highlighted that m^(6)A RNA modification plays an important role in im-mune response,especially in the initiation and progression of autoimmune *** this re-view,we summarized the regulatory mechanisms of m^(6)A methylation and its biological functions in the immune system and mainly focused on recent progress in research on the po-tential role of m^(6)A RNA methylation in the pathogenesis of autoimmune diseases,thus providing possible biomarkers and potential targets for the prevention and treatment of auto-immunediseases.

关键词： Adaptive immunity Autoimmune diseases Innate immunity Immune response m^(6)A RNA methylation

Price Masking Strategy of Cross-Border E-Commerce Platform Financing

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Journal of Systems Science & Complexity 2024年第2期37卷 668-691页

作者： LI Jianbin HANG Zhouxin chen Zhiyuan XIAO shan School of Management Huazhong University of Science and TechnologyWuhan 430074China School of Economics and Management Wuhan UniversityWuhan 430072China

E-commerce platform financing is a new service pattern of supply chain ***,this pattern may bring some new issues when considering the problem of cash flow shortage and financing difficulties of small and medium-sized *** enterprises use this service,they worry about the leakage of preferential wholesale price when applying the full loan amount and providing the true transaction *** on the model consisting of a supplier,a retailer and a cross-border e-commerce platform,the authors design a price masking strategy to prevent the retailer’s preferential wholesale price information from *** authors analyze the profit of the retailer and the platform before and after adopting the price masking *** authors find that the price masking strategy always benefits the ***,the optimal profit of the retailer and the platform are both affected by the loan interest ***,there exists a range of loan interest rates that can benefit both the retailer and the platform if the price masking strategy is *** research emphasizes that platform can expand the total business volume by allowing retailers to use price masking *** other words,there will be more and more retailers attracted by the strategy,which benefits the long-term growth of cross-border e-commerce platform financing.

关键词： Cross-border e-commerce e-commerce platform financing price masking supply chain finance