Improvement of electrical characteristics of InGaZnO thin film transistors by using HMDSO/O2 plasma deposited SiOCH buffer layer

Liu Chang,Qin Houyun,Liu Yiming,Wei Song,Wang Hongbo,Zhao Yi 한국물리학회 2021 Current Applied Physics Vol.21 No.-

In this work, we present the performance improved InGaZnO thin film transistors by inserting low temperature processed 10 nm thick SiOCH buffer layers between SiNx insulator and InGaZnO channel layer. The influences of oxygen flow rate during the deposition of SiOCH buffer layer have been intensively investigated. Basing on the analysis of hall effect measurement and Fourier transform infrared spectrum, the SiOCH buffer layer can effectively increase the carrier concentration of the channel layer by the hydrogen doping due to re-sputtering and diffusion effect. The InGaZnO thin film transistor with buffer layer exhibits an enhanced performance with mobility of 13.09 cm2/vs, threshold voltage of 0.55 V and Ion/Ioff over 106.

Pharmacokinetics and Biodistribution of Surface Modification Polymeric Nanoparticles

Liu, Mingxing,Li, Huifang,Luo, Guoan,Liu, Qingfei,Wang, Yiming 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.4

The objective of this study is to investigate the pharmacokinetics and biodistribution of free breviscapine (BVP) and coated BVP-loaded poly (D, L-lactic acid) nanoparticles (BVP-PLA-NPs) in rats after i.v. administration. Coated BVP-PLA-NPs were prepared by the spontaneous emulsification solvent diffusion method and characterized. The BVP content in the NPs, the biological samples and in vitro release was measured by the high-performance liquid chromatography (HPLC). The mean sizes of coated BVP-PLA-NPs were 177 and 319 nm with a narrow distribution and smooth sphere shapes, entrapment efficiency of 86.9% and 93.1%, respectively. Drug release profiles in phosphate buffer and plasma exhibited a biphasic release phenomenon. After i.v. administration of free BVP and NPs suspensions in rats, area under plasma concentration-time curve and elimination $t_{1/2}$ were increased 9.3-fold and 10.9-fold for 177 nm of NPs, and 4.4-fold and 17.1-fold for 319 nm of NPs compared with that of free BVP, respectively. NPs were mainly distributed in liver, spleen, heart and brain. In addition, NPs could penetrate blood brain barrier (BBB) and the particle size had some effect on pharmacokinetics and biodistribution. Coated BVP-PLA-NPs could effectively avoid the capture by the reticuloendothelial system and prolong the half-life of BVP. Moreover, these NPs could penetrate BBB and enhance the accumulation of BVP in brain.

Adaptive Stabilization of Feedforward Time-delay Systems with Uncertain Output Equation

Yiming Shao,Xianglei Jia,Wenhui Liu,Guobao Liu 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.4

In this work, the problem of global adaptive stabilization is solved by output feedback for a family of feedforward nonlinear time-delay systems with uncertain output equation and unknown growth rate. To deal with system uncertainty, a low-gain observer incorporating with novel adaptive gain is first proposed. Next, via output feedback, an adaptive delay-free controller is constructed by combining scaling change with backstepping algorithm. Compared with existing results, the controller proposed is capable of handling both uncertain output equation and unknown delay. With the aid of Lyapunov-Krasovskii functional and Barbalat ˘ ’s lemma, it is shown that the state and its estimate converge asymptotically to zero, and the adaptive gain is bounded. Furthermore, by numerical simulations, the usefulness of the control scheme is illustrated.

Macro-Micro Mechanical Behavior of Crushable Granular Materials under Generalized Stress Conditions

Yiming Liu,Chenming Xu,Guofang Xu,Haijun Mao,Zunqun Xiao 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.5

This paper investigated the joint influence of particle crushing and intermediate principal stress coefficient on the macro and micro performances of granular assembles by using 3D discrete element method. The soil particle was modeled by crushable agglomerate. Numerical true triaxial tests with crushable agglomerates were performed. The mechanical behaviors of specimens with unbreakable agglomerates were also tested in this study. The results demonstrated that grain breakage can significantly affect the behaviors of granular soils in both macro and micro scales. Moreover, the present paper also showed that particle breakage did not influence the unique relationship between the intermediate principal stress coefficient band the deviatoric fabric of strong contacts. This can provide a good basis for developing micro-parameter-based constitutive model considering particle breakage for granular soils.

Pharmacokinetics and Biodistribution of Surface Modification Polymeric Nanoparticles

Mingxing Liu,Huifang Li,Guoan Luo,Qingfei Liu,Yiming Wang 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.4

The objective of this study is to investigate the pharmacokinetics and biodistribution of free breviscapine (BVP) and coated BVP-loaded poly (D, L-lactic acid) nanoparticles (BVP-PLANPs) in rats after i.v. administration. Coated BVP-PLA-NPs were prepared by the spontaneous emulsification solvent diffusion method and characterized. The BVP content in the NPs, the biological samples and in vitro release was measured by the high-performance liquid chromatography (HPLC). The mean sizes of coated BVP-PLA-NPs were 177 and 319 nm with a narrow distribution and smooth sphere shapes, entrapment efficiency of 86.9% and 93.1%, respectively. Drug release profiles in phosphate buffer and plasma exhibited a biphasic release phenomenon. After i.v. administration of free BVP and NPs suspensions in rats, area under plasma concentration-time curve and elimination t1/2 were increased 9.3-fold and 10.9-fold for 177 nm of NPs, and 4.4-fold and 17.1-fold for 319 nm of NPs compared with that of free BVP, respectively. NPs were mainly distributed in liver, spleen, heart and brain. In addition, NPs could penetrate blood brain barrier (BBB) and the particle size had some effect on pharmacokinetics and biodistribution. Coated BVP-PLA-NPs could effectively avoid the capture by the reticuloendothelial system and prolong the half-life of BVP. Moreover, these NPs could penetrate BBB and enhance the accumulation of BVP in brain.

Separation of chalcopyrite from galena with 3-amyl-4-amino-1, 2, 4-triazole-5-thione collector: Flotation behavior and mechanism

Zhiyong Zhang,Yiming Wang,Guangyi Liu,Sheng Liu,Jun Liu,Xianglin Yang 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.92 No.-

3-Amyl-4-amino-1,2,4-triazole-5-thione (AATT) reacted with Cu2+ or Pb2+ ions in aqueous solutions toform CuAATT and Pb(AATT)2 complexes and their solubility product constants were measured as 10 16.17and 10-20.60, respectively. In the moderately-alkaline media, both chalcopyrite and galena chemisorbedAATT on to their surfaces, and the adsorption amount of AATT on chalcopyrite was bigger than that ongalena, which rendered a stronger hydrophobization toward chalcopyrite. While under the high-alkalinepulp, AATT only chemisorbed on chalcopyrite, not on galena. The micro-flotationfindings indicated thatAATT was a favorable collector forflotation enrichment of chalcopyrite and galena at pH <11.0, andrealized an efficientflotation separation of chalcopyrite from galena under pH>11.5. The CuAATTcomplexwas more insoluble than Pb(AATT)2, which implied a stronger affinity of AATT toward chalcopyrite thangalena and returned their selectiveflotation separation at the high-alkaline condition.

Performance of Homologous and Heterologous Prime-Boost Immunization Regimens of Recombinant Adenovirus and Modified Vaccinia Virus Ankara Expressing an Ag85B-TB10.4 Fusion Protein against Mycobacterium tuberculosis

( Yiming Kou ),( Mingming Wan ),( Wei Shi ),( Jie Liu ),( Zhilei Zhao ),( Yongqing Xu ),( Wei Wei ),( Bo Sun ),( Feng Gao ),( Linjun Cai ),( Chunlai Jiang ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.6

Tuberculosis (TB) remains a serious health issue around the word. Adenovirus (Ad)-based vaccine and modified vaccinia virus Ankara (MVA)-based vaccine have emerged as two of the most promising immunization candidates over the past few years. However, the performance of the homologous and heterologous prime-boost immunization regimens of these two viral vector-based vaccines remains unclear. In the present study, we constructed recombinant Ad and MVA expressing an Ag85B-TB10.4 fusion protein (AdH4 and MVAH4) and evaluated the impact of their different immunization regimens on the humoral and cellular immune responses. We found that the viral vector-based vaccines could generate significantly higher levels of antigen-specific antibodies, IFN-γ-producing splenocytes, CD69⁺CD8⁺ T cells, and IFN-γ secretion when compared with bacillus Calmette-Guerin (BCG) in a mouse model. AdH4-containing immunization regimens (AdH4-AdH4, AdH4-MVAH4, and MVAH4-AdH4) induced significantly stronger antibody responses, much more IFN-γ-producing splenocytes and CD69⁺CD8⁺ T cells, and higher levels of IFN-γ secretion when compared with the MVAH4-MVAH4 immunization regimen. The number of IFN-γ-producing splenocytes sensitive to CD8⁺ T-cell restricted peptides of Ag85B (9-1p and 9-2p) and Th1-related cytokines (IFN-γ and TNF-α) in the AdH4-MVAH4 heterologous prime-boost regimen immunization group was significantly higher than that in the other viral vector-based vaccine- and BCG-immunized groups, respectively. These results indicate that an immunization regimen involving AdH4 may have a higher capacity to induce humoral and cellular immune responses against TB in mice than that by regimens containing BCG or MVAH4 alone, and the AdH4-MVAH4 prime-boost regimen may generate an ideal protective effect.

FTESO-based Nonsingular Fast Integral Terminal Sliding Mode Finite Time Control for the Speed and Tension System of the Cold Strip Rolling Mill

Le Liu,Ranyang Deng,Zhuang Ma,Yiming Fang 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.1

To weaken the influences of uncertainties on the finite time tracking control performance of the speed and tension system of the reversible cold strip rolling mill driven by alternating current (AC) asynchronous motors, a dynamic surface backstepping nonsingular fast integrated terminal sliding mode control (DSBNFITSMC) strategy is proposed based on finite time extended state observers (FTESOs). Firstly, the FTESOs are constructed to dynamically observe the system’s mismatched uncertainties, and the observation errors can converge to zero in finite time. Next, the dynamic surface backstepping control is combined with the nonsingular fast integrated terminal sliding mode finite time control to complete the controller designs for the speed and tension system of the reversible cold strip rolling mill, which solve the “differential explosion” problem in conventional backstepping control, and simplify the design processes of the system controllers. Again, theoretical analysis shows that the proposed control strategy can guarantee the closed-loop system is practical finite time stability in the Lyapunov sense. Finally, the simulation research is carried out on the speed and tension system of a reversible cold strip rolling mill by using the actual data, and results show the validity of the proposed control strategy.

Nonlinear Sliding Mode Tracking Control of Underactuated Tower Cranes

Zhuoqing Liu,Ning Sun,Yiming Wu,Xin Xin,Yongchun Fang 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.2

As representative underactuated systems, tower cranes exhibit high nonlinearity and strong state coupling, which makes their controller design (analysis) challenging and of great research values. In addition, since tower cranes are widely applied in outdoor environment with inevitable external disturbances, (the state variables tend to go far away from the equilibrium point), how to ensure the control performance in this case is particularly important; moreover, most existing control methods can only ensure closed loop stability, but cannot theoretically ensure the system states convergence time. Considering the above factors, this paper proposes a nonlinear sliding mode tracking controller, which can realize satisfactory tracking performance and effective swing suppression. To our knowledge, for tower cranes, this is the first tracking method designed based upon the nonlinear dynamics without any linearization, which can eliminate the tracking errors rapidly in finite time by introducing the elaborately constructed sliding mode surface and simultaneously suppress the swing. Furthermore, through rigorous analysis, the system closed loop stability is proven theoretically. Finally, hardware experiments imply that the proposedcontroller is effective and exhibits satisfactory robustness.

Quantification of Mechanical Twins in Metallographic Images of Twinning-Induced Plasticity Steels Using a New Image Processing Method

Yi Liu,Yiming Yu,Tuanwei Zhang,Renlong Xiong,Hyoung Seop Kim 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.4

A new image-processing method based on block-gradient segmentation was proposed to measure the volume fraction ofmechanical twins in metallographic images. The processing results showed that this automatic method could be used forrapid and effective measure of the twin-volume fractions of twinning-induced plasticity steels in metallographic images underdifferent strain conditions. The entire processing time for each image is relatively short, which would benefit researchersprocessing a large number of metallographic images. This method may pave a way to develop a simple, effective plug-in tomeasure rapidly the twin-volume fractions in the software for metallographic observations, and it would be beneficial forpreliminary analysis of microstructural evolutions and subsequent characterization of mechanical twins by high-resolutionmicroscopy using electron microscopy.