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Characterization of self-assembled monolayers of porphyrins bearing multiple-thiol and photoelectric response

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Chinese Chemical Letters 2012年第8期23卷 977-980页

作者： Jian Dong Yang Xiao quan lu Department of Biology and Chemistry Longnan Normal CollegeChengxian 742500China Key Lab of Bioelectrochemisty&Environmental Analysis of Gansu Province College of the Chemistry and Chemical EngineeringNorthwest Normal of UniversityLanzhou 730070China

Self-assembled monolayers（SAMs） of thiol-derivatized porphyrin molecules on Au substrate have attracted extensively interest for use in sensing,optoelectronic devices and molecular *** this paper,tetra-[p-（3-mercaptopropyloxy）-phenyl]porphyrin was synthesized and self-assembled with thiol on Au substrate for porphyrin SAMs（PPS 4）.The electrochemical results demonstrated that PPS 4 could form excellent SAMs on gold ***-assembled nanojunctions of PPS 4 were fabricated by using gold nanogap electrodes（gap width：ca.100 nm）.With the light on/off,the nanojunctions showed current high/low as nanometer scaled photo switch.

关键词： Porphyrin Self-assembled monolayer Characterization Photo switch

Observation of Bi Coarsening and Dissolution Behaviors in Melting Al–Bi Immiscible Alloy

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Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 800-803页

作者： Wen-quan lu Shu-Guang Zhang Jian-Guo Li School of Materials Science and Engineering Shanghai Jiao Tong University School of Environmental Science and Engineering Shanghai Jiao Tong University

Using synchrotron radiography, a melting process of the AI-10 wt% Bi immiscible alloy was fully observed, and Bi solute coarsening and dissolution behaviors as well as their effect on the microstructural evolution were also investi- gated. We found that two different steps including coarsening and dissolution processes can be used to describe the structure evolution in melting AI-10 wt% Bi immiscible alloy. And diffusion coalescence controlled the coalescence of Bi droplets at the early stage of the melting AI-10 wt% Bi immiscible alloy, while the coagulation dttring movement did at later stage. Also, the larger the droplet, the larger the distance of the steady-state concentration distribution around the droplet.

关键词： Immiscible alloy Coarsening Dissolution Synchrotron radiography

Cloning and sequence analysis of nine novel MYB genes in Taxodiaceae plants

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Journal of Forestry Research 2014年第4期25卷 795-804页

作者： Yong-quan lu Qing JIA Zai-kang TONG The Nurturing Station for the State Key Laboratory of Subtropical Silviculture Zhejiang Agriculture and Forestry University

Myeloblastosis （MYB） is one of the largest transcribed factor families in plants. To gain an overall picture of the evolution of MYB genes in relict plants, we cloned nine novel MYB genes in Taxodiaceae plants （ Taxodium distichum, Taxodium ascendens, Cryptomeria japonica var. Sinensis, Cryptomeria japonica cv. Araucarioides, Cryptomer Ja- ponica, Metasequoia glyptostroboides, Cunninghamia lanceolata, Tai- wania cryptomerioides and Glyptostrobus pensilis）. The deduced amino acid sequences for MYBs showed that the nine MYB proteins contained two DNA binding domains. The first domain is from amino acid position 29 to 78, wherein three tryptophanes at 33, 53 and 73 were separated by 19 amino acids, respectively. The second domain is from amino acid position 82 to 127, wherein three tryptophanes at 86, 105 and 124 were separated by 18 amino acids, respectively, whereas the first tryptophane at amino acid position 86 is replaced by a phenylalanine. The characteri- zation of these conserved domains at nine MYBs indicated that they all belong to the R2R3-MYB group. The secondary structure analysis showed that a-helix and 13-turn are the major motifs of the predicted secondary structure of MYBs. The three dimensional model of each MYB protein showed that the structure is like clip, making it more flexi- ble and mobile. The similarities between the nine MYB proteins in Taxodiaceae were calculated. The highest identical value of 99% is be- tween CjsMYB, CjMYB and CjaMYB, whereas the lowest value of 82% is between TaMYB and C1MYB. According to the phylogenetic tree, the distances between different genera were relatively large whereas those within genera were relatively small. As expected, accessions of the same genus formed a subgroup before being grouped with other genera.

关键词： Myeloblastosis Taxodiaceae clone analysis R2R3-MYB group

Fault diagnosis and isolation of the componentand sensor for aircraft engine

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航空动力学报 2012年第6期27卷 1432-1440页

作者： QIU Xiao-jie HUANG Jin-quan lu Feng LIU Nan College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Aircraft engine component and sensor fault detection and isolation approach was proposed,which included fault type detection module and component-sensor simultaneous fault isolation *** approach can not only distinguish among sensor fault,component fault and component-sensor simultaneous fault,but also isolate and locate sensor fault and the type of engine component fault when the engine component fault and the sensor faults occur *** double-threshold mechanism has been proposed,in which the fault diagnostic threshold changed with the sensor type and the engine condition,and it greatly improved the accuracy and robustness of sensor fault diagnosis *** results show that the approach proposed can diagnose and isolate the sensor and engine component fault with improved *** effectively improves the fault diagnosis ability of aircraft engine.

关键词： aircraft engine sensor fault engine component fault simultaneous fault diagnosis isolation double-threshold mechanism

NUMERICAL ANALYSIS OF THE UNSTEADY FORCE IN INSECT FORWARD FLIGHT

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Journal of Hydrodynamics 2006年第2期18卷 143-147页

作者： ZHA Xiong-quan lu Xi-yun YIN Xie-zhen Department of Mechanics and Mechanical Engineering University of Science and Technology of China Hefei 230026 China

The objective of this study is to get into physical insights to the unsteady force and the relevant mechanisms in forward flight of insects. Unsteady force in the forward flight was studied, based on a virtual model problem of a foil with oscillating translation and rotation in a uniform flow, by solving the two-dimensional incompressible Navier-Stokes equations with a finite element method. The effects of typical parameters, including the advance ratio, the inclined angle of stroke plane, the stroke amplitude, and the amplitude of pitching angle of attack, on the forces and the flow structures were analyzed.

关键词： unsteady flow vortex dynamics thrust and lift,flapping motion biomechanics

Cross-Shock Electrostatic Potential and Ion Reflection in Quasi-Parallel Supercritical Collisionless Shocks

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Chinese Physics Letters 2012年第8期29卷 318-321页

作者： SU Yan-Qing lu quan-Ming CAS Key Laboratory of Basic Plasma Physics Department of Geophysics and Planetary ScienceUniversity of Science and Technology of ChinaHefei 230026 State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190

The time evolution of the cross-shock electrostatic potential jump during one specific high Mach number quasi-parallel shock reformation cycle is examined via a 1D hybrid *** is shown that when the average value of the electrostatic potential jump is low,its instant value can be large so that the shock is in a favorable profile to directly reflect the incident *** simulation also suggests that,for the ones that finally become injected ions(which can be further accelerated by diffusive shock acceleration mechanism),the first step of their reflections should be mainly attributed to the electrostatic potential jump,instead of the magnetic force,as stated in some previous studies.

关键词： electrostatic shock stated

Delay-dependent robust control for uncertain discrete singular systems with time-varying delay

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1034-1042页

作者： Hui-jiao WANG Xiao-dong ZHAO An-ke XUE Ren-quan lu Institute of Automation Zhejiang Sci- Tech University Hangzhou 310018 China Institute of Information and Control Hangzhou Dianzi University Hangzhou 310018 China

The design problem of delay-dependent robust control for uncertain discrete singular systems with time-varying delay is addressed in this paper. The uncertainty is assumed to be norm-bounded. By establishing a finite sum inequality based on quadratic terms, a new delay-dependent robust stability condition is derived and expressed in terms of linear matrix inequalities (LMIs). A suitable robust state feedback control law is presented, which guarantees that the resultant closed-loop system is regular, causal and stable for all admissible uncertainties. Numerical examples are given to demonstrate the applicability of the proposed method.

关键词： Uncertain discrete singular system Time-varying delay Robust control Linear matrix inequality (LMI)

Input-output approach to robust stability and stabilization for uncertain singular systems with time-varying discrete and distributed delays

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 546-551页

作者： Hui-jiao WANG An-ke XUE Yun-fei GUO Ren-quan lu Institute of Automation Zhej iang Sci- Tech University Hangzhou 310018 China Institute of Information and Control Hangzhou Dianzi University Hangzhou 310018 China

Based on input-output approach, the robust stability and stabilization problems for uncertain singular systems with time-varying delays are investigated. The parameter uncertainties are assumed to be norm-bounded and the time-varying delays include both discrete delay and distributed delay. By introducing a new input-output model, the time-delay system is embedded in a family of systems with a forward system without time delay and a dynamical feedback uncertainty. A sufficient and necessary condition, which guarantees the system regular, impulse-free and stable for all admissible uncertainties, is obtained. Based on the strict linear matrix inequality, the desired robust state feedback controller is also obtained. Finally, a numerical example is provided to demonstrate the application of the proposed method.

关键词： Robust stability Input-output stability Singular system Time-varying delay Linear matrix inequality (LMI)

Cooling and wetting of soil decelerated ground freezingethawing processes of the active layer in Xing'an permafrost regions in Northeast China

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Advances in Climate Change Research 2023年第1期14卷 126-135页

作者： Bo-quan lu Shu-Ying ZANG Li-quan SONG Li SUN Miao LI Di BING Heilongjiang Province Key Laboratory of Geographical Environment Monitoring and Spatial Information Service in Cold Regions Harbin Normal UniversityHarbin 150025China Heilongjiang Province Collaborative Innovation Center of Cold Region Ecological Safety Harbin 150025China

The accelerated or decelerated freezingethawing processes of the active layer in Xing'an permafrost regions are crucial for the protection of *** better understand the freezingethawing processes of the active layer and its driving factors,according to the observation from 2017 to 2020 of soil temperature and water content in the active layer of forest and peatland in two representative hemiboreal ecosystems in the Da Xing'anling Mountains,Northeast China,the study explored in detail the effects of climatic conditions and local factors on the hydrothermal and freezingethawing processes of active layer *** results showed that during the freezingethawing cycles of 2017-2020,freezing and thawing start times in the peatland and forest ecosystems soils were generally delayed,and it took longer for the active layer soil to completely thaw than to *** annual average soil temperature in the peatland's active layer(5-80 cm)was 0.7-2.0℃ lower than that in the forest,and the annual average soil moisture content on the peatland was 5.5%-26.7%higher than that in the *** with the forest ecosystem soils,the ground surface freezing time of the peatland was delayed by 3e10 d,and the freezing rate decreased by 1.1-1.5 cm d1,while the beginning time of thawing was advanced by 22-27 d,and the thawing rate decreased by 1.3-1.4 cm d^(-1).In the process of decreasing soil temperature and increasing soil moisture content,the freezing and thawing rate of the active layer would be reduced,decelerating the freezingethawing processes of the active layer in the process of decreasing soil temperature and increasing soil moisture *** results provide the key original data for studying the formation and evolution of active layer and permafrost in the Xing'an permafrost regions in Northeast China and can be used to validate the prediction of ecosystem succession under the combined influences of climate change and permafrost degradation.

关键词： Freezingethawing processes Hydrothermal dynamics Active layer Hemiboreal ecosystems Xing'an permafrost