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Journal of Integrative Plant Biology 2011年第5期53卷 347-357页

作者： Lu zhou Jin duan Laboratory of Molecular Biology and MOE Laboratory of Protein Science School of Life Sciences Tsinghua University Beijing 100084China

Plant annexins represent a multigene family involved in cellular elongation and development. A cDNA encoding a novel annexin was isolated from a cotton （Gossypium hirsutum） fiber cDNA library and designated GhAnxl. This gene encodes a 316 amino acid protein with a theoretical molecular mass of 36.06 kDa and a theoretical pl of 6.19. At the amino acid level, it shares high sequence similarity and has evolutionary relationships with annexins from higher plants. The purified recombinant protein expressed in Escherichia coil was used to investigate its physicochemical properties. Circular dichroism spectrum analyses showed a positive peak rising to the maximum at 196 nm and a broad negative band rounding 215 nm, suggesting that the GhAnxl protein was prominently α-helical. The fluorescence measurements indicated that it could bind to Ca2 in vitro. These results demonstrated that GhAnxl was a typical annexin protein in cotton. A bioassay experiment was conducted to analyze its potential function and showed that E. coil cells expressing GhAnxl were protected from tert-butyl hydroperoxide （tBH） stress, suggesting that it had a potential antioxidative role. Northern blot analyses revealed that GhAnxl was highly expressed in fibers, especially during the elongation stage, suggesting that it might be important for fiber elongation.

关键词： LIPOCORTINS RECOMBINANT proteins ANTIOXIDANTS COTTON GENETICS ANTISENSE DNA PLANT bioassay AMINO acid sequence

Coverage of communication-based sensor nodes deployed location and energy efficient clustering algorithm in WSN

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Journal of Systems Engineering and Electronics 2010年第4期21卷 698-704页

作者： Xiang Gao Yintang Yang duan zhou College of Microelectronics Xidian University Xi' an 710071 P. R. China College of Computer Science and Technology Xidian University Xi'an 710071 E R. China

An effective algorithm based on signal coverage of effective communication and local energy-consumption saving strategy is proposed for the application in wireless sensor *** algorithm consists of two *** is the multi-hop partition subspaces clustering algorithm for ensuring local energybalanced consumption ascribed to the deployment from another algorithm of distributed locating deployment based on efficient communication coverage probability（DLD-ECCP）.DLD-ECCP makes use of the characteristics of Markov chain and probabilistic optimization to obtain the optimum topology and number of sensor *** simulation,the relative data demonstrate the advantages of the proposed approaches on saving hardware resources and energy consumption of networks.

关键词： wireless sensor network probability distribution function Markov chain received signal strength indicator Gaussian distribution.

Fast motion estimation algorithm for H.264/AVC based on centered prediction

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Journal of Systems Engineering and Electronics 2010年第6期21卷 1103-1110页

作者： Wei zhou Zhemin duan Hongqi Hu School of Electronics and Information Northwestern Polytechnical University Xi'an 710072 P. R. China

H.264/AVC video coding standard can achieve roughly half of the bit-savings over MPEG2 and MPEG4 for a given quality. However, this comes at a cost in considerably increased complexity at the encoder and thus increases the difficulty in hardware implementation. The high redundancy that exists between the successive frames of a video sequence makes it possible to achieve a high data compression ratio. Motion estimation （ME） plays an important role in motion compensated video coding. A fast motion estimation algorithm for H.264/AVC is proposed based on centered prediction, called centered prediction based fast mixed search algorithm （CPFMS）. It makes use of the spatial and temporal correlation in motion vector （MV） fields and feature of all-zero blocks to accelerate the searching process. With the initialized searching point prediction, adaptive search window changing and searching direction decision, CPFMS is provided to reduce computation in block-matching process. The experimental results show that the speed of CPFMS is nearly 12 times of FS with a negligible peak signal-noise ratio （PSNR） loss. Also, the efficiency of CPFMS outperforms some popular fast algorithms such as hybrid unsymmetrical cross multi-hexagongrid search and a novel multidirectional gradient descent search evidently.

关键词： H.264/AVC motion estimation motion vectors early termination.

An Asynchronous Adaptive Priority Round-Robin Arbiter Based on Four-Phase Dual-rail Protocol

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Chinese Journal of Electronics 2015年第1期24卷 1-7页

作者： YANG Yintang WU Ruizhen ZHANG Li zhou duan School of Microelectronics Xidian University School of Computer Science and Technology Xidian University

An asynchronous Adaptive priority roundrobin arbiter(APRA) based on four-phase dual-rail protocol is proposed. Combining the advantages of synchronous and asynchronous circuits, it provides the required bandwidth allocation on basis of arbitration fairness and works in synchronous So C. In the Nonidling and nonpreemptive(NINP) model, simulations and verifications are made. The results show that the speed of the proposed arbiter is improved by 18%–50.4% and the dynamic and static power is reduced by 8.4%–46.2% and 81.8%–90.9% respectively compared with the commonly-used Fixed priority(FP),Round-Robin(RR) and Lottery arbiters. The proposed arbiter is better in output bandwidth allocation and it also has advantages in speed and power. Furthermore, it is easy in reconfiguration, strong in practicability and low in complexity of system integration and suits various extreme communication traffics.

关键词： Arbiter Asynchronous circuit Fourphase dual-rail protocol System-on-chip(So C).

GLOBAL STABILIZATION OF LINEAR SYSTEMS WITH BOUNDED CONTROLS USING STATE-DEPENDENT SATURATION FUNCTIONS

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Journal of Systems Science & Complexity 2011年第3期24卷 477-490页

作者： Bin zhou Guangren duan He KONG Center for Control Theory and Guidance Technology Harbin Institute of Technology Harbin 150001 China.

By using the so-called SP-stable polynomials, this paper reconsiders the problem of global stabilization of linear systems with input saturation. Firstly, a new nonlinear feedback law consisting of parallel connections of saturation functions by means of the so-called state-dependent saturation function is proposed for global stabilization of chains of integrators system. The state-dependent saturation function allows increasing the control energy when some of the states are badly scaled and can improve significantly the transient performances of the closed-loop system. Secondly, this type of global stabilization nonlinear feedback laws is extended to a class of linear systems that can be globally stabilized by bounded controls. Numerical examples show the effectiveness of the proposed approach.

关键词： Bounded feedback global stabilization nonlinear control state-dependent saturation functions SP-stable polynomials.

Cooling Torsional Nanomechanical Vibration by Spin-Orbit Interactions

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Communications in Theoretical Physics 2008年第12期50卷 1457-1460页

作者： ZHAO Nan zhou duan-Lu ZHU Jia-Lin Department of Physics Tsinghua University Beijing 100084 China Institute of Physics Chinese Academy of Science Beijing 100080 China

We propose and study a spin-orbit interaction based mechanism to actively cool down the torsional vibrationof a nanomechanical resonator made by semiconductor *** show that the spin-orbit interactions of electronscan induce a coherent coupling between the electron spins and the torsional modes of nanomechanical *** leads to an active cooling for the torsional modes through the dynamical thermalization of the resonator by thespin ensemble.

关键词： nanoelectromeehanical system spin-orbit interaction dynamical thermalization

Idealization Second Quantization of Composite Particles

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Communications in Theoretical Physics 2001年第11期36卷 525-530页

作者： zhou duan-Lu YU Si-Xia SUN Chang-Pu Institute of Theoretical Physics Academia SinicaBeijing 100080China Institute of Theoretical PhysicsAcademia SinicaBeijing 100080China Institute of Theoretical PhysicsAcademia SinicaBeijing 100080China

A practical method is developed to deal with the second quantization of the many-body system containing the composite *** our treatment,the modes associated with composite particles are regarded approximately as independent ones compared with those of unbound *** field operators of the composite particles thus arise naturally in the second quantization *** be emphasized,the second quantization Hamiltonian has the regular structures which correspond clearly to different physical processes.

关键词： second quantization,composite particles

Influence of Marine Aerobic Biofilms on Corrosion of 316L Stainless Steel

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Journal of Iron and Steel Research International 2015年第8期22卷 715-720页

作者： Feng-ling XU Ji-zhou duan Cun-guo LIN Bao-rong HOU State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research Institute Key Laboratory of Marine Environmental Corrosion and Bio-fouling Institute of Oceanology Chinese Academy of Sciences

The influence of marine aerobic biofilms on the corrosion of 316L stainless steel （SS） in aerated and deaerated seawater was studied by electrochemical impedance spectroscopy （EIS）, potentiodynamic polarisation curves, current-potential curves and scanning electron microscopy with energy-dispersive spectroscopy （SEM-EDS）. EIS and SEM-EDS results showed that the aero- bic biofilms inhibited 316L SS corrosion within the test duration. Comparison of results under aerated and deaerated conditions revealed that 02 enhanced the inhibition efficiency of the aerobic biofilms. This result indicated that living cells were necessary for the aerobic biofilms to inhibit the corrosion of 316L SS. Polarization curves indicated that the biofilms mainly inhibited anode ac- tion. Current-potential curves under deaerated conditions showed that electron transfer processes occurred between microorganisms and electrodes. Moreover, 316L SS as an electron acceptor was protected from corrosion.

关键词： 316L stainless steel microbiologically influenced corrosion polarisation curve

Uncertainty relation of successive measurements based on Wigner-Yanase skew information

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Communications in Theoretical Physics 2022年第1期74卷 25-30页

作者： Jun Zhang Jia-Ning Wei zhou-Bo duan Kan He Chang-Shui Yu College of Data Science Taiyuan University of TechnologyTaiyuan 030024China College of Mathematics Institute of MathematicsTaiyuan University of TechnologyTaiyuan 030024China School of Physics Dalian University of TechnologyDalian 116024China

Wigner-Yanase skew information could quantify the quantum uncertainty of the observables that are not commuting with a conserved *** present the uncertainty principle for two successive projective measurements in terms of Wigner-Yanase skew information based on a single quantum *** could capture the incompatibility of the observables,*** lower bound can be nontrivial for the observables that are incompatible with the state of the quanaim ***,the lower bound is also constrained by the quantum Fisher *** addition,we find the complementarity relation between the uncertainties of the observable which operated on the quantum state and the other observable that performed on the post-measured quantum state and the uncertainties formed by the non-degenerate quantum observables performed on the quantum state,respectively.

关键词： quantum uncertainty relation successive measurements Wigner-Yanase skew information

Inhibition of Zinc Corrosion by Fucoidan in Natural Sea water

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Acta Metallurgica Sinica(English Letters) 2017年第6期30卷 594-600页

作者： Cui Wang Jie Zhang Xiao-Lin Chen Bin Xiang Ji-zhou duan Bao-Rong Hou College of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China Key Laboratory of Marine Environmental Corrosion and Biofouling Institute of OceanologyChinese Academy of SciencesQingdao 266071China Institute of Oceanology Chinese Academy of SciencesQingdao 266071China

Research on corrosion behaviour of zinc in natural sea water without and with fucoidan was carried out by potentiodynamic polarisation test and electrochemical impedance spectroscopy （EIS）. The results revealed that fucoidan serves as a good inhibitor for zinc in sea water. Polarisation curves suggested that corrosion potential values shifted to the positive ones after adding inhibitor and fucoidan retards anodic reaction more. Thus, fucoidan can be acted as anodic inhibitor. EIS results showed two phenomena including a charge transfer and an adsorption film. The corrosion inhibition of fucoidan was further confirmed by the scanning electron microscope （SEM） and atomic force microscope （AFM） analysis. Langmuir＇s adsorption isotherm was found the appropriate adsorption model.

关键词： Zinc Polarisation EIS AFM XRD Anodic protection