A STUDY ON THE MATHEMATICAL MODEL OF PCT CURVE OF $Mm_{0.6} Ml_{0.4} Ni_{5-X}Co_X$ HYDROGEN STORAGE ALLOYS

Ziqiang, Zhou,Feng, Feng,Jinglong, Zhang,Yihui, Xiong,Xinyi, Ping,Qun, Huang 한국재료학회 1995 Fabrication and Characterization of Advanced Mater Vol.1 No.1

The pressure-composition-temperature(PCT) curves of $Mm_{0.6}Ml_{0.4}Ni_{5_x}Co_{x}(x{\leqslant}2.5)$hydrogne stroage alloys(HSA) are determined and the mathermatical model of PCT curve the author proposed is applied to analyse the data of PCT curve of the alloy system. It been shown from the results that the PCT curve of $Mm_{0.6}Ml_{0.4}Ni_{5-x}Co_{x}$can also be modeled by the mathematical model and the calculated PCT curves are in good agreement with the experimental curves. A lot of physical parameters of these alloys which are very useful are estimated from the modeling.

Applications of Heavy Ion Irradiation in Photonic Crystal Research

Ziqiang Zhao,Yingmin Liu,Yan Chen,Ding Lan,Yuren Wang 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.6

Photonic crystals (PC) have received extensive attention for the photonic band gap (PBG). The polystyrene (PS) particles bottom-up approach is a productive method for photonic crystal manufacture, this kind of photonic crystals having an unique PBG that depends on the particle’s shape, sizes and defects. Heavy ion irradiation is a very useful method to induce defects in PC and change the shapes of the particles to tune the PBG. MeV heavy ion irradiation leads to an anisotropic deformation of the particles from spherical to ellipsoidal, the aspect ratio of which can be precisely controlled by using the ion energy and flux. Sub-micrometer PS particles were deposited on a Cu substrate and were irradiated at 230 K by using heavy ion energy and fluence in the range from 2 to 10 MeV and 1 × 1014 cm−2 to 1 × 1015 cm−2, respectively. Photonic crystals (PC) have received extensive attention for the photonic band gap (PBG). The polystyrene (PS) particles bottom-up approach is a productive method for photonic crystal manufacture, this kind of photonic crystals having an unique PBG that depends on the particle’s shape, sizes and defects. Heavy ion irradiation is a very useful method to induce defects in PC and change the shapes of the particles to tune the PBG. MeV heavy ion irradiation leads to an anisotropic deformation of the particles from spherical to ellipsoidal, the aspect ratio of which can be precisely controlled by using the ion energy and flux. Sub-micrometer PS particles were deposited on a Cu substrate and were irradiated at 230 K by using heavy ion energy and fluence in the range from 2 to 10 MeV and 1 × 1014 cm−2 to 1 × 1015 cm−2, respectively.

Bipartite Consensus of Nonlinear Discrete-time Multi-agent Systems via Variable Impulsive Control

Ziqiang Xu,Yun Li,Xiang Hu,Chuandong Li,Yiyan Han 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.2

This paper addresses the bipartite consensus of the nonlinear discrete-time multi-agent systems on network where cooperation and confrontation exist simultaneously. The communication graph has negative weights to represent antagonistic interaction among agents. Two kinds of distributed variable impulsive protocols are designed for case with leader and leaderless. Compared with existing fixed-time impulsive protocols, the action instant of variable impulsive protocol is in a time window and not fixed, which is more suitable for practical application. By employing Lyapunov function approach and comparison system theorem, the results reveal that the bipartite leaderless consensus and bipartite tracking consensus can be achieved. Meanwhile, the rate of bipartite consensus possess the characteristic of exponential, if some conditions are met. Finally, the effectiveness of the consensus analysis is verified by three simulation examples.

Effects of Different Atmosphere on Electrochemical Performance of Hard Carbon Electrode in Sodium Ion Battery

Ziqiang Xu,Jinchen Chen,Mengqiang Wu,Cheng Chen,Yaochen Song,Yuesheng Wang 대한금속·재료학회 2019 ELECTRONIC MATERIALS LETTERS Vol.15 No.4

Hard carbon is deemed to be a most promising anode materials for sodium—ion batteries (SIBs), while, the issues of lowcapacity and low initial coulombic efficiency still exist limiting the development of SIBs. Although high temperature carbonizationof biomass materials under nitrogen or argon atmosphere is a common method for preparation of hard carbon,there are few reports about the effects of different protective atmospheres on propriety of hard carbon. In this article, hornet’snest (HN) is used to prepare hard carbon under nitrogen and argon. At a suitable carbonization temperature (1200 °C and1400 °C), the hard carbon under argon possesses lower specific surface area (25–50 cm−3 g−1), but higher initial coulombefficiency (4–6%) and higher capacity retention (3–6%). Thus, it is inferred that high—performance hard carbon can beobtained under argon atmosphere. Our research about the effect of sintering atmosphere on material properties is expectedto provide a reference for the synthetization of hard carbon by high temperature carbonization.

A Robust Video Fingerprinting Algorithm Based on Centroid of Spatio-temporal Gradient Orientations

( Ziqiang Sun ),( Yuesheng Zhu ),( Xiyao Liu ),( Liming Zhang ) 한국인터넷정보학회 2013 KSII Transactions on Internet and Information Syst Vol.7 No.11

Video fingerprints generated from global features are usually vulnerable against general geometric transformations. In this paper, a novel video fingerprinting algorithm is proposed, in which a new spatio-temporal gradient is designed to represent the spatial and temporal information for each frame, and a new partition scheme, based on concentric circle and rings, is developed to resist the attacks efficiently. The centroids of spatio-temporal gradient orientations (CSTGO) within the circle and rings are then calculated to generate a robust fingerprint. Our experiments with different attacks have demonstrated that the proposed approach outperforms the state-of-the-art methods in terms of robustness and discrimination.

Fabrication of diarylide yellow pigments/modified SiO2 core–shell hybrid composite particles for electrophoretic displays

Ziqiang Wen,Yaqing Feng,Xianggao Li,Xiaoxu Li,Yu Bai,Qingmeng Tang,Yidan Gao 한국물리학회 2012 Current Applied Physics Vol.12 No.1

Diarylide yellow pigments/modified SiO2 coreeshell hybrid composite particles were fabricated via a newly developed two-step procedure. The surface of diarylide yellow pigments was coated with SiO2by the hydrolysis of Na2SiO3. The obtained particles were then modified with in situ generated 3-aminopropylsilanetriol or succinic acid to form composite particles containing amino or carboxyl groups. The FT-IR spectra, TGA and TEM showed that the particles had a coreeshell structure, the SEM suggested that the surface morphology of the composite particles was smooth, and the XPS and zeta potential measurement indicated that the composite particles had a high charge load. The obtained composite particles have been applied as electrophoretic particles in the electronic paper, which demonstrated that the newly developed procedure is an effective way to produce various organic/inorganic composite particles used for electrophoretic displays.

Effect of the raceway defects on the nonlinear dynamic behavior of rolling bearing

Ziqiang Zhao,Xuebin Yin,Wenzhong Wang 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.6

The defects on raceways would aggravate the vibration of bearing and greatly influence the bearing performance, in order to monitor the running state of the bearing and detect the early defect, the characteristics induced by the defect must be explored. This paper establishes a bearing dynamic model to explore the effect of raceway defects on the nonlinear dynamic behavior of rolling element bearing. The interaction between ball and races is modeled based on Hertz theory, while the presence of defects changes the ball-race interaction. The effects of defect size, position and number on bearing dynamic behaviors are investigated with the aid of phase trajectories, shaft center orbits, FFT spectra, etc. The results indicate that the defects can make the motion of the system more complicated and induce vibration at some characteristic frequencies, which can be used to recognize the bearing failure at early stage. The proposed research provides useful information for the design and status monitoring of mechanical systems.

Sciatic nerve leachate of cattle causes neuronal differentiation of PC12 cells via ERK1/2 signaling pathway

Ziqiang Zhang,Yumei Liu,Xuemin Zhu,Lan Wei,Jiamin Zhu,Ke Shi,Guotao Wang,Li Pan 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.4

Previous studies have shown that the sciatic nerve has neurotrophic activity, and nerve regeneration, differentiation, and axon outgrowth can be modulated by different sciatic nerve preparations. However, numerous animals may have to be sacrificed to obtain enough sciatic nerves to make a sciatic nerve preparation. Some studies have demonstrated that the role of sciatic nerve preparations in neural differentiation depends on the neurotrophins that Schwann cells secrete, and these factors are highly conserved among different species. To reduce the use of experimental animals, in this study, we made a leachate by using the sciatic nerve of cattle and explored its effect on neuronal differentiation of rat PC12 cells (a useful model for studying neuronal differentiation). Results showed the neurite outgrowth of PC12 cells treated with the cattle sciatic nerve leachate for 3, 6, and 9 days was significantly improved, and the expressions of β3-tubulin and microtubule-associated protein 2 (two neuron-specific proteins) were increased. Moreover, the ERK1/2 signaling pathway was activated after PC12 cells were incubated with cattle sciatic nerve leachate for 9 days. Thus, a sciatic nerve leachate obtained from cattle can effectively induce neuronal differentiation of rat PC12 cells via ERK1/2 signaling pathway.

An Improved DCT-based Image Watermarking Scheme

Ziqiang Cheng(청즈치앙),Dae-Soo Kim(김대수),Kee-Young Yoo(유기영) 대한전자공학회 2010 대한전자공학회 학술대회 Vol.2010 No.6

Many DCT-based watermarking schemes have been proposed in the past few years. In 2009, Lin et al proposed a scheme that focused on resisting JPEG compression attack. However, it fails to verify ownership when cropping reconstruction attack is applied, and the watermarked image degrades quite significantly after embedding watermark bits. In order to solve these problems of Lin et al’s scheme, an improved scheme was proposed in this paper. The experimental results show that the proposed scheme resist on cropping reconstruction attack, and also achieve better invisibility than Lin et al’s scheme.

Rigid-flexible coupling dynamic modeling and performance analysis of a bioinspired jumping robot with a six-bar leg mechanism

Ziqiang Zhang,Lun Wang,Jinnong Liao,Jing Zhao,Qi Yang 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.8

The rigid-flexible coupling structure of creatures with jumping ability has the advantages of high stiffness and good flexibility, which are of great significance to its research. However, existing research on jumping robots has not demonstrated the effect of multiflexibility links on the jumping performance. In this paper, a Watt-type one degree-of-freedom six-bar mechanism is regarded as research object. For a jumping leg including multiple flexible links and a flexible joint with a floating frame, a rigid-flexible coupling dynamic model is established with a pseudo-rigid-body model being used. On this basis, the effect of structural and installation parameters on the jumping performance is analyzed. Results show that different flexible links have distinct effects on the jumping performance, and properly reducing the stiffness of flexible links can improve the jumping performance. The results of this study provide a design basis for jumping robots with a rigid-flexible coupling structure.