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A hybrid artificial photosynthesis system with molecular catalysts covalently linked onto TiO2 as electron relay for efficient photocatalytic hydrogen evolution

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Journal of Materials Science & Technology 2020年第15期47卷 147-152页

作者： Jie zhang Gehong zhang jing zhang School of Civil and Architecture Engineering Xi'an Technological UniversityXi'an710021China

Efficient charge carrier transfer from light harvesters to catalysts greatly determines the photocatalytic activity in an artificial photosynthesis(AP) system for solar hydrogen *** this study,an AP system composed of xanthene dye as light harvester and cobaloxime molecular complex as catalyst,with TiO2 as electron relay,was designed for photocatalytic hydrogen evolution under visible light(λ>420 nm).It was demonstrated that with cobaloxime molecule covalently linked onto the TiO2 electron relay,the resulting hybrid AP system exhibited much increased photocatalytic activity as compared to that without *** greatly increased photocatalytic activity should be due to the efficient electron transfer from xanthene dye as light harvester and cobaloxime molecular complex as catalyst,shuttled by the TiO2 electron relay,for the following water reduction *** present study demonstrates a facile and feasible strategy to guide the design of high performance AP systems through the electron relay shuttled and promoted cha rge transfer process.

关键词： Artificial photosynthesis Molecular catalysts Electron relay Photocatalytic hydrogen evolution

A Dugdale-Barenblatt model for elliptical orifice problem with asymmetric cracks in one-dimensional orthorhombic quasicrystals

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Applied Mathematics and Mechanics(English Edition) 2023年第9期44卷 1533-1546页

作者： jing zhang Guanting LIU College of Mathematics Science Inner Mongolia Normal UniversityHuhhot 010022China

By means of Muskhelishvili’s method and the technique of generalized conformal mapping,the physical plane problems are transformed into regular mathematical problems in quasicrystals(QCs).The analytical solution to an elliptical orifice problem with asymmetric cracks in one-dimensional(1D)orthorhombic QCs is *** using the Dugdale-Barenblatt model,the plastic simulation at the crack tip of the elliptical orifice with asymmetric cracks in 1D orthorhombic QCs is ***,the size of the atomic cohesive force zone is determined precisely,and the size of the atomic cohesive force zone around the crack tip of an elliptical orifice with a single crack or two symmetric cracks is obtained.

关键词： one-dimensional(1D)orthorhombic quasicrystal(QC) Dugdale-Barenblatt model atomic cohesive force zone crack

On Lower Dimensional Invariant Toriin C^d Reversible Systems

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Chinese Annals of Mathematics,Series B 2008年第5期29卷 459-486页

作者： jing zhang School of Mathematical Sciences Peking University Beijing 100871 China

In this paper, a result on the persistence of lower dimensional invariant tori in Cd reversible systems is obtained under some conditions. The theorem is proved for any d which is larger than some constants.

关键词： Reversible systems Lower dimensional invariant tori KAM step

Name disambiguation in AMiner

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Science China(Information Sciences) 2021年第4期64卷 214-216页

作者： jing zhang Jie TANG Information School Renmin University of China Department of Computer Science and Technology Tsinghua University

Name disambiguation, aiming at disambiguating who is who, is one of the fundamental problems of the online academic network platforms such as Google scholar, microsoft academic and AMiner. This study takes AMiner;), a free online academic search and mining system [1], as the example to explain how we deal with the name ambiguity problem under three different scenarios.

关键词： name disambiguation academic network graph embedding outlier detection clustering algorithm

Tool State Detection by Harmonic Wavelet and Sample Entropy

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Chinese Journal of Mechanical Engineering 2011年第6期24卷 1068-1073页

作者： SONG Wanqing zhang jing College of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai 201620China

It is a fact that acoustic emission(AE) signals contain potentially valuable information for tool wear and breakage monitoring and ***,AE stress waves produced in the cutting zone are distorted by the transmission path and the measurement systems,it is difficult to obtain a reliable result by these raw AE *** is generally known that the process of tool wear belongs to detect weak singularity signals in strong *** objective of this paper is to combine Newland Harmonic wavelet and Richman-Moorman(2000) sample entropy for detecting weak singularity signals embedded in strong ***,the raw AE signal is decomposed by harmonic wavelet and transformed into the three-dimensional time-frequency mesh map of the harmonic wavelet,at the same time,the contours of the mesh map with log space is ***,the profile map of the three-dimensional time-frequency mesh map is offered,which corresponds to decomposed level on harmonic ***,by computing sample entropy in each level,the weak singularity signal can be easily extracted from strong *** test was carried out on HL-32 NC turning *** lathe does not have a *** carbide finishing tool was used to turn free machining mild *** work material was chosen for ease of machining,allowing for generation of surfaces of varying quality without the use of cutting *** turning experiments,the feasibility for tool condition monitoring is demonstrated by 27 kinds of cutting conditions with the sharp tool and the worn tool,54 group data are sampled by *** sample entropy of each level of wavelet decomposed for each one of 54 AE datum is computed,wear tool and shaper tool can be distinguished obviously by the sample entropy value at the 12th level,this is a *** proposed research provides a new theoretical basis and a new engineering application on the tool condition monitoring.

关键词： tool wear harmonic wavelet sample entropy

Modeling Study of Foehn Wind Events in Antarctic Peninsula with WRF Forced by CCSM

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Journal of Meteorological Research 2018年第6期32卷 909-922页

作者： Chongran zhang jing zhang Applied Science and Technology Program North Carolina A & T State University Department of Physics North Carolina A & T State University

Significant changes have occurred in the Antarctic Peninsula(AP) including warmer temperatures, accelerated melting of glaciers, and breakup of ice shelves. This study uses the Weather Research and Forecasting model(WRF)forced by the Community Climate System Model 4(CCSM) simulations to study foehn wind warming in AP. Weather systems responsible for generating the foehn events are two cyclonic systems that move toward and/or cross over AP. WRF simulates the movement of cyclonic systems and the resulting foehn wind warming that is absent in CCSM. It is found that the warming extent along a transect across the central AP toward Larsen C Ice Shelf(LCIS) varies during the simulation period and the maximum warming moves from near the base of leeward slopes to over 40 km away extending toward the attached LCIS. Our analysis suggests that the foehn wind warming is negatively correlated with the incoming air temperature and the mountain top temperature during periods without significant precipitation, in which isentropic drawdown is the dominant heating mechanism. On the other hand, when significant precipitation occurs along the windward side of AP, latent heating is the major heating mechanism evidenced by positive relations between the foehn wind warming and 1) incoming air temperature, 2) windward precipitation, and 3)latent heating. Foehn wind warming caused by isentropic drawdown also tends to be stronger than that caused by latent heating. Comparison of WRF simulations forced by original and corrected CCSM data indicates that foehn wind warming is stronger in the original CCSM forced simulation when no significant windward precipitation is *** foehn wind warming becomes weaker in both simulations when there is significant windward precipitation. This suggests that model’s ability to resolve the foehn warming varies with the forcing data, but the precipitation impact on the leeward warming is consistent.

关键词： foehn wind warming Antarctic Peninsula melting Weather Research and Forecasting(WRF) model Community Climate System Model(CCSM) forcing

Construction of solitonary and periodic solutions to some nonlinear equations using EXP-function method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 660-664页

作者： zhang Mei zhang Wen-jing Department of Applied Physics College of Science Donghua University Shanghai 201620 China

This paper applies the EXP-function method to find exact solutions of various nonlinear equations. Tzitzeica- Dodd-Bullough (TDB) equation was selected to illustrate the effectiveness and convenience of the suggested method. More generalized solitonary solutions with free parameters were obtained by suitable choice of the free parameters, and also the obtained solitonary solutions can be converted into periodic solutions.

关键词： Soliton Periodic solution Nonlinear equation EXP-function method

Observer-based distributed consensus for nonlinear multi-agent systems with limited data rate

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Science China(Information Sciences) 2022年第9期65卷 191-205页

作者： jing zhang Shuai LIU Xianfu zhang School of Control Science and Engineering Shandong University

In this paper, we investigate the observer-based distributed consensus problem for nonlinear multi-agent systems with a limited data rate. We assume that each agent displays strict-feedback nonlinear dynamics. An observer is constructed to estimate the system states as they cannot be directly *** quantizers and logarithmic quantizers are considered in communication channels among agents and observer-based distributed control protocols are proposed for each agent. For the uniform quantizer, theδ-asymptotic distributed consensus, with δ being the resolution of the quantizer, can be achieved under the proposed control protocol, i.e., the consensus errors tend to zero as δ approaches zero. For the logarithmic quantizer, the asymptotic consensus can be achieved. The simulation results reveal the conclusion.

关键词： nonlinear multi-agent systems uniform quantizer logarithmic quantizer dynamic gain $\delta$-asymptotic distributed consensus

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Effects of minocycline on apoptosis and neuronal changes in retinal ganglion cells from experimental optic neuritis rats

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Neural Regeneration Research 2008年第12期3卷 1348-1351页

作者： jing zhang Department of Ophthalmology First Affiliated Hospital Chongqing Medical University Chongqing 400016 China

BACKGROUND： Minocycline, a tetracycline derivative, is neuroprotective in models of various neurological diseases. OBJECTIVE： To investigate the effects of minocycline on retinal ganglion cells （RGCs） in rats with optic neuritis, and to compare with the effects of methylprednisolone. DESIGN, TIME AND SETTING： This neuropathology controlled study was performed at the First Affiliated Hospital, Chongqing Medical University, China in May 2007. MATERIALS： A total of 22 female Wistar rats were randomly assigned into a normal control group （n ： 5） and an experimental group （n = 17）. The experimental group was composed of a model subgroup （n = 7）, a minocycline subgroup （n = 5）, and a methylprednisolone subgroup （n = 5）. Minocycline was supplied by Sigma, USA. METHODS： Antigen homogenate made from guinea pig spinal cord and complete Freund adjuvant was used to induce autoimmune encephalomyelitis, which could induce demyelinated optic neuritis models. Rats in the minocycline subgroup were intraperitoneally injected with minocycline （45 mg/kg） daily from day 8 following autoimmunity. Rats in the methylprednisolone subgroup were intraperitoneally injected with methylprednisolone （20 mg/kg） daily from day 8 following autoimmunity. MAIN OUTCOME MEASURES： On day 18 after autoimmunily induction, pathological changes in the optic nerve were observed by hematoxylin-eosin staining. The percentage area of axons in the transverse section of the optic nerve was measured by Bielschowsky staining. Apoptosis of RGCs was detected by TUNEL. RESULTS： Under an optical microscope, the optic nerve in rats with demyelinated optic neuritis showed a vacuole-like structure of fibers, irregular swelling of the axons, and infiltration of a large quantity of inflammatory cells. With an electron microscope, the optic nerve presented with vacuole-like structures in the axons, a small percentage area of axons in the transverse section, loose myelin sheaths, and microtubules and microfilaments disappeared

关键词： optic neuritis retinal ganglion cells minocycline methylprednisolone