The impact of Mg content on the structural, electrical and optical properties of MgZnO alloys: A first principles study

Yonghong Hu,Bo Cai,Ziyu Hu,Yanli Liu,Shengli Zhang,Haibo Zeng 한국물리학회 2015 Current Applied Physics Vol.15 No.3

The structural, electronic and optical properties of wurtzite MgZnO with Mg concentration ranging from 0 to 0.5 are studied using the first principle calculations. It's found that the lattice constants c and specific volume V of the MgZnO alloys decrease and their band gap widens as Mg concentration increases, which are in agreement with our experimental results. A particular Mg concentration is found to exist at around 0.375, equals to which the corresponding MgZnO alloy has the minimum width of the top valence band. This indicates that Mg concentration may be used to tune the electronic properties of MgZnO alloy. Meanwhile, it's also found that the energy response range of the optical spectrums decreases with the increase of Mg concentration. There are different energy shifts toward high energy (blue shift) of the peaks in the optical spectrums with the increase of Mg concentration, which are explained by the variations of the density of states in details. So the electronic and optical properties of MgZnO may be tuned through Mg concentration, and our research results may provide meaningful references to the development and design of photoelectric devices.

Evolution of the optical spectra of an Ag/mesoporous SiO₂ nanostructure heat-treated in air and H₂ atmospheres

Hu, Jinlian,Lee, Woong,Cai, Weiping,Tong, Liuniu,Zeng, Haibo IOP Pub 2007 Nanotechnology Vol.18 No.18

<P>Evolution of the various optical spectra of Ag nanoparticles dispersed in mesoporous SiO<SUB>2</SUB> after heating alternately in H<SUB>2</SUB> and air atmospheres has been investigated. It has been observed that, in accordance with alternate heat treatment in H<SUB>2</SUB> and air, surface plasmon resonance (SPR) absorption of the Ag/mesoporous SiO<SUB>2</SUB> nanostructure alternately appeared and disappeared and its Raman scattering spectra reversibly increased and decreased. In contrast, its photoluminescence (PL) spectra alternately disappeared and appeared, whereas the infrared (IR) spectra did not change. Such novel optical sensitivities of silver nanoparticles are discussed on the basis of the changes in chemical states of silver induced by the interaction of silver nanoparticles with the atmospheres and the hosting medium. It is suggested that the chemical state of silver in mesoporous SiO<SUB>2</SUB> changes reversibly between Ag and the Ag<SUP>+</SUP> ion by the redox process. </P>

Design of Evaluation Index System for Information Experience based on B2C e- Commerce Bigdata and Artificial Intelligence

강장묵,Haibo HU,Yinghui CHEN,이상원 한국인터넷방송통신학회 2019 Journal of Advanced Smart Convergence Vol.8 No.4

The online retail market continues to grow, especially in China, as e-commerce has developed rapidly in recent years in many countries. Meanwhile, the development and use of new network information technology provides consumers with various contact and experience environments for online shopping. Based on the theory of media weakness, the study began to focus consumer experience on the nature of commercial transactions. The study proposed and designed an initial measure of the consumer information evaluation index, which combines previous findings with implications. Finally, the five-dimensional B2C system was established to evaluate consumers' information experience providing information display, information interaction, information support and information personalization. We researched on evaluation index system for information experience of B2C e-commerce consumers based on samples of Chinese consumers.

Formation Mechanisms for (Cr,Co)7C3/(Cr,Co)23C6 Heterogeneous Precipitates and Stacking Faults Around Carbides in Surfacing Welding of Stellite Alloy on Stainless Steel

Jiankun Xiong,Haibo Zhang,Fuheng Nie,Fen He,Jianping Yang,Zhan Hu,Zhongbo Wen,Haiyan Zhao,Xinjian Yuan 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

The formation mechanisms for two carbides with co-existence and increasing stacking faults nearby the carbides duringsurfacing welding were investigated in this study. The results indicated that the surfacing layer had a two-phase structure ofa matrix phase and a second phase, the density of the second phase was relatively small and the second phase was discontinuous,by contrast with the as-received welding wire. Relatively uniform microstructure of surfacing layer and the weldinginterface without melting of base metal were obtained, resulting in an inapparent change in the microhardness. A few carbideswith blocky shape were identified in the surfacing layer. The mechanisms for (Cr,Co)23C6 of face-centered cubic crystalstructure co-existing with (Cr,Co)7C3 of hexagonal close-packed crystal structure and (Cr,Co)23C6 subsequently forming closeto the pre-formed (Cr,Co)7C3 during the cooling process were discussed in alloying element, calculated equilibrium phasediagram, Gibbs energy, etc. The relatively higher density of the stacking fault present around the carbides was understoodfrom forming energy of stacking faults.

Design of Evaluation Index System for Information Experience based on B2C e-Commerce Bigdata and Artificial Intelligence

KANG, Jangmook,HU, Haibo,CHEN, Yinghui,LEE, Sangwon The Institute of Internet 2019 International journal of advanced smart convergenc Vol.8 No.4

The online retail market continues to grow, especially in China, as e-commerce has developed rapidly in recent years in many countries. Meanwhile, the development and use of new network information technology provides consumers with various contact and experience environments for online shopping. Based on the theory of media weakness, the study began to focus consumer experience on the nature of commercial transactions. The study proposed and designed an initial measure of the consumer information evaluation index, which combines previous findings with implications. Finally, the five-dimensional B2C system was established to evaluate consumers' information experience providing information display, information interaction, information support and information personalization. We researched on evaluation index system for information experience of B2C e-commerce consumers based on samples of Chinese consumers.

The USP21/YY1/SNHG16 axis contributes to tumor proliferation, migration, and invasion of non-small-cell lung cancer

Pei Xu,Haibo Xiao,Qi Yang,Rui Hu,Lianyong Jiang,Rui Bi,Xueyan Jiang,Lei Wang,Ju Mei,Fangbao Ding,Jianbing Huang 생화학분자생물학회 2020 Experimental and molecular medicine Vol.52 No.-

Deubiquitinases (DUBs) and noncoding RNAs have been the subjects of recent extensive studies regarding their roles in lung cancer, but the mechanisms involved are largely unknown. In our study, we used The Cancer Genome Atlas data set and bioinformatics analyses and identified USP21, a DUB, as a potential contributor to oncogenesis in nonsmall-cell lung cancer (NSCLC). We further demonstrated that USP21 was highly expressed in NSCLCs. We then conducted a series of in vitro and in vivo assays to explore the effect of USP21 on NSCLC progression and the underlying mechanism involved. USP21 promoted NSCLC cell proliferation, migration, and invasion and in vivo tumor growth by stabilizing a well-known oncogene, Yin Yang-1 (YY1), via mediating its deubiquitination. Furthermore, YY1 transcriptionally regulates the expression of SNHG16. Moreover, StarBase bioinformatics analyses predicted that miR4500 targets SNHG16 and USP21. A series of in vitro experiments indicated that SNHG16 increased the expression of USP21 through miR-4500. In summary, the USP21/YY1/SNHG16 axis plays a role in promoting the progression of NSCLC. Therefore, the USP21/YY1/SNHG16/miR-4500 axis may be a potential therapeutic target in NSCLC treatment.

Effect of Transformation Temperature on the Ferrite–Bainite Microstructures, Mechanical Properties and the Deformation Behavior in a Hot-Rolled Dual Phase Steel

Bo Jiang,Xuewen Hu,Leyu Zhou,Haibo Wang,Yazheng Liu,Fugang Gou 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.2

The ferrite–bainite microstructures and mechanical properties in a hot-rolled dual phase steel with different transformationtemperatures were investigated in this paper. The deformation behavior of bainite and ferrite was analyzed by using in situscanning electron microscope. The results showed that the ferrite and bainite can be refined and the volume fraction of bainitecan be slightly increased by 5% by decreasing the ferrite transformation temperature from 690 to 635 °C and increasing thebainite transformation temperature from 400 to 450 °C. The strengthening mechanism was dislocation difference in polygonaland acicular ferrite and then the grain size difference of ferrite. The hole expansion ratio increased from 52.9 to 83.7% withthe ferrite transformation temperature decreasing. The cracks or voids were smaller in size and also the number in steel withthe lower ferrite transformation temperature after expanding. The microstructure separation along the boundary betweenbainite and ferrite and the slip band in the ferrite appeared at the non-uniform deformation stage. However, fewer appearedin the microstructure of steel with lower ferrite transformation temperature. Cooperative deformation of ferrite and bainiteand finer microstructure in steel with lower ferrite transformation temperature were the mechanisms why the cracks couldnot easily nucleated and propagated, respectively. Thus this was also why there was a better hole expansion ratio.

Microstructural Characterization and Softening Mechanism of Ultra-Low Carbon Steel and the Control Strategy in Compact Strip Production Process

Bo Jiang,Xuewen Hu,Guoning He,Huan Peng,Haibo Wang,Yazheng Liu 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.9

In this paper, the microstructures and properties of hot rolled ultra-low carbon steel sheet produced by different compact stripproduction (CSP) processes were investigated. The softening mechanism was also discussed and the control strategy wasproposed in order to obtain optimum properties. Result showed that the average ferrite grain sizes of austenite rolling sheetand multiphase rolling sheet were 31.0 μm and 74.6 μm, respectively. The sheet after austenite rolling had a slightly higheryield and tensile strength while had a 6.3% higher elongation than that of the sheet after multiphase rolling. The higher dislocationin the sheet after multiphase rolling increased the strength while decreased the elongation. The softening mechanismof the sheet after multiphase rolling was the coarsening of ferrite grain. The combined role of {001} and {111} orientationresulted in a slight increase of the r and ̄rvalue in the sheet after multiphase rolling. It was a wise choice to conduct rollingat the Ac1temperature in CSP process to increase the grain size and decrease the dislocation density. Then, the strength ofthe sheets could be further reduced and the elongation could also be improved.

Filter-based Immersion and Invariance Adaptive Control of Nonlinear Systems

Wei Chen,Jian Hu,Jianyong Yao,Weirong Nie,Haibo Zhou 제어·로봇·시스템학회 2024 International Journal of Control, Automation, and Vol.22 No.1

This paper proposes a novel filter-based immersion and invariance (I&I) adaptive method for nonlinear systems with additive disturbances and parameter uncertainties. The key innovation of the proposed method is a filter construction that involves the dynamics of the system, based on which the I&I parameter estimator with a sigma modification term is designed. Comparing existing I&I methods, the expression for the novel filter-based I&I estimator is given in terms of total derivatives rather than partial derivatives, which is no longer subject to the integrability condition. In combining the sigma modification term, the proposed parameter estimator also guarantee the uniformly ultimately bounded stability of the parameter estimation error when the system is disturbed, which cannot be achieved by the original I&I method. Furthermore, Lyapunov theory demonstrates that the proposed method can guarantee the stability of the nonlinear systems discussed in this paper. Simulation and experimental results confirm the effectiveness of the proposed method.

Prediction on the physical properties of CuInS2 with various anion positions

Yiming Ren,Yonghong Hu,Haibo Zeng,Li Xue 한국물리학회 2018 Current Applied Physics Vol.18 No.3

The effects of various anion displacements (u) on electronic structures, elastic constants, Debye temperature and the minimum thermal conductivity of CuInS2 are studied by first-principles calculation. The lattice constant couples with the anion displacement, however, they are not consistent with the relation proposed by Abrahams and Bernstein. When the anion displacement varies from 0.2 to 0.3, the Cu-S bond length is elongated, while the In-S bond length is shortened, which cause the increase of band gap with anion displacement. The anisotropies of sound velocities and lattice thermal conductivities are also discussed. The results imply that the lattice thermal conductivity along [110] direction is the smallest and decreases with u. These research findings shed light on improving the thermoelectric properties by manipulating u and the direction of propagation.