Direct Electrochemistry and Electrocatalysis of Myoglobin with CoMoO₄ Nanorods Modified Carbon Ionic Liquid Electrode

Zhao, Zengying,Cao, Lili,Hu, Anhui,Zhang, Weili,Ju, Xiaomei,Zhang, Yuanyuan,Sun, Wei Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.2

By using ionic liquid 1-hexylpyridinium hexafluorophosphate ($HPPF_6$) based carbon ionic liquid electrode (CILE) as the substrate electrode, a $CoMoO_4$ nanorods and myoglobin (Mb) composite was casted on the surface of CILE with chitosan (CTS) as the film forming material to obtain the modified electrode (CTS/$CoMoO_4$-Mb/CILE). Spectroscopic results indicated that Mb retained its native structures without any conformational changes after mixed with $CoMoO_4$ nanorods and CTS. Electrochemical behaviors of Mb on the electrode were carefully investigated by cyclic voltammetry with a pair of well-defined redox peaks from the heme Fe(III)/Fe(II) redox center of Mb appeared, which indicated that direct electron transfer between Mb and CILE was realized. Electrochemical parameters such as the electron transfer number (n), charge transfer coefficient (${\alpha}$) and electron transfer rate constant ($k_s$) were estimated by cyclic voltammetry with the results as 1.09, 0.53 and 1.16 $s^{-1}$, respectively. The Mb modified electrode showed good electrocatalytic ability toward the reduction of trichloroacetic acid in the concentration range from 0.1 to 32.0 mmol $L^{-1}$ with the detection limit as 0.036 mmol $L^{-1}$ ($3{\sigma}$), and the reduction of $H_2O_2$ in the concentration range from 0.12 to 397.0 ${\mu}mol\;L^{-1}$ with the detection limit as 0.0426 ${\mu}mol\;L^{-1}$ ($3{\sigma}$).

Direct Electrochemistry and Electrocatalysis of Myoglobin with CoMoO4 Nanorods Modified Carbon Ionic Liquid Electrode

Zengying Zhao,Lili Cao,Anhui Hu,Weili Zhang,Xiaomei Ju,Yuanyuan Zhang,Wei Sun 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.2

By using ionic liquid 1-hexylpyridinium hexafluorophosphate (HPPF6) based carbon ionic liquid electrode (CILE) as the substrate electrode, a CoMoO4 nanorods and myoglobin (Mb) composite was casted on the surface of CILE with chitosan (CTS) as the film forming material to obtain the modified electrode (CTS/ CoMoO4-Mb/CILE). Spectroscopic results indicated that Mb retained its native structures without any conformational changes after mixed with CoMoO4 nanorods and CTS. Electrochemical behaviors of Mb on the electrode were carefully investigated by cyclic voltammetry with a pair of well-defined redox peaks from the heme Fe(III)/Fe(II) redox center of Mb appeared, which indicated that direct electron transfer between Mb and CILE was realized. Electrochemical parameters such as the electron transfer number (n), charge transfer coefficient (α) and electron transfer rate constant (ks) were estimated by cyclic voltammetry with the results as 1.09, 0.53 and 1.16 s−1, respectively. The Mb modified electrode showed good electrocatalytic ability toward the reduction of trichloroacetic acid in the concentration range from 0.1 to 32.0 mmol L−1 with the detection limit as 0.036 mmol L−1 (3σ), and the reduction of H2O2 in the concentration range from 0.12 to 397.0 μmol L− 1 with the detection limit as 0.0426 μmol L−1 (3σ).

The effect of volume conservation based on nucleon scattering analysis for W isotopes

Du Wenqing,Zhao Xiuniao,Sun Weili,Soukhovitskiĩ E. Sh. 한국물리학회 2021 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.79 No.6

On the basis of soft-rotor model, a good description of nucleon scattering on tungsten and neighboring nuclei was achieved in J. Phys. G: Nucl. Part. Phys. 48, 075101 (2021), and the nuclear volume conservation condition was introduced. The effect of volume conservation on calculations for tungsten isotopes is further investigated by defining the ratio R for cross sections, scattering angular distributions and analyzing powers. The results show that the volume conservation effect cannot be ignored. This effect is more significant in the low-energy region of cross sections and at extrema of angular distributions. Comparison between the calculated results and existing nuclear data evaluations in different evaluated nuclear data libraries is shown.

A Better Approximation Algorithm for Computing Connected Dominating Sets in Unit Ball Graphs

Donghyun Kim,Zhao Zhang,Xianyue Li,Wei Wang,Weili Wu,Ding-Zhu Du IEEE 2010 IEEE TRANSACTIONS ON MOBILE COMPUTING Vol.9 No.8

<P>A Virtual Backbone (VB) of a wireless network is a subset of nodes such that only VB nodes are responsible for routing-related tasks. Since a smaller VB causes less overhead, size is the primary quality factor of VB. Frequently, Unit Disk Graphs (UDGs) are used to model 2D homogeneous wireless networks, and the problem of finding minimum VBs in the networks is abstracted as Minimum Connected Dominating Set (MCDS) problem in UDGs. In some applications, the altitude of nodes can be hugely different and UDG cannot abstract the networks accurately. Then, Unit Ball Graph (UBG) can replace UDG. In this paper, we study how to construct quality CDSs in UBGs in distributed environments. We first give an improved upper bound of the number of independent nodes in a UBG, and use this result to analyze the Performance Ratio (PR) of our new centralized algorithm C-CDS-UBG, which computes CDSs in UBGs. Next, we propose a distributed algorithm D-CDS-UBG originated from C-CDS-UBG and analyze its message and time complexities. Our theoretical analysis shows that the PR of D-CDS-UBG is 14.937, which is better than current best, 22. Our simulations also show that D-CDS-UBG outperforms the competitor, on average.</P>

On minimum submodular cover with submodular cost

Du, Hongjie,Wu, Weili,Lee, Wonjun,Liu, Qinghai,Zhang, Zhao,Du, Ding-Zhu Springer-Verlag 2011 Journal of global optimization Vol.50 No.2

A Spectroscopic Study on Singlet Oxygen Production from Different Reaction Paths Using Solid Inorganic Peroxides as Starting Materials

Li, Qingwei,Chen, Fang,Zhao, Weili,Xu, Mingxiu,Fang, Benjie,Zhang, Yuelong,Duo, Liping,Jin, Yuqi,Sang, Fengting Korean Chemical Society 2007 Bulletin of the Korean Chemical Society Vol.28 No.10

Using solid inorganic peroxides (including Li2O2, Na2O2, SrO2 and BaO2) as starting materials, three reaction paths for singlet oxygen (1O2) production were developed and studied. Their 1O2 emission spectra in the near- IR region and visible region from these reaction paths were simultaneously recorded by a near-IR sensitive Optical Multichannel Analyzer and a visible sensitive Optical Spectrum Analyzer, respectively. The comparison of their 1O2 emission spectra indicated that: (1) in term of the efficiency for 1O2 production, the gasliquid- solid reaction path (in which Cl2 or HCl and H2O reacted with the solid inorganic peroxides suspension in CCl4) was prior to the gas-solid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides suspension in CCl4), but was inferior to the gas-liquid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides solution in H2O or D2O); (2) the alkali metal peroxides (such as Li2O2 and Na2O2) was prior to the alkaline earth metal peroxides (such as SrO2 and BaO2) as the solid reactants, and Cl2 was favorable than HCl as the gas reactant in efficiency for 1O2 production in these reaction paths.

Aqueous Synthesis and Photocatalytic Performance of Bi5O7I Microflowers

Yuehong Song,Xinli Hao,Weili Dai,Jingzhe Zhao 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.4

Bi5O7I microflowers were synthesized through a simple liquid coprecipitation under alkaline condition at 75 ℃ in an open system without using autoclave or other complex equipment. The addition of NaBr was a key factor for controlling the morphology of Bi5O7I. The assembled Bi5O7I samples are constructed by elementary nanowires, which were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and UV-Vis diffuse reflection spectroscopy (UV-Vis DRS) methods. The photocatalytic performance of Bi5O7I samples on rhodamine B (RhB), methylene blue (MB) and ciprofloxacin (CIP) was evaluated under 350 W xenon lamp irradiation. On comparison with the blank Bi5O7I microflowers, Bi5O7I microflowers with NaBr addition exhibited better photocatalytic performance, and the photocatalytic activity enhanced with the increase of NaBr amount. The photocatalytic efficiency reached 81.1% in 150 min for RhB, 42.5% in 210 min for MB and 56.3% in 210 min for CIP in the degradation system at pH = 7 without any assistant agent. Trapping experiments were performed to reveal the degradation mechanism of Bi5O7I samples. It was proposed that valid separation of photogenerated electrons and holes in Bi5O7I microflowers led to good catalytic properties.

A Spectroscopic Study on Singlet Oxygen Production from Different Reaction Paths Using Solid Inorganic Peroxides as Starting Materials

Qingwei Li*,Fang Chen,Weili Zhao,Mingxiu Xu,Benjie Fang,Yuelong Zhang,Liping Duo,Yuqi Jin,Fengting Sang 대한화학회 2007 Bulletin of the Korean Chemical Society Vol.28 No.10

Using solid inorganic peroxides (including Li2O2, Na2O2, SrO2 and BaO2) as starting materials, three reaction paths for singlet oxygen (1O2) production were developed and studied. Their 1O2 emission spectra in the near-IR region and visible region from these reaction paths were simultaneously recorded by a near-IR sensitive Optical Multichannel Analyzer and a visible sensitive Optical Spectrum Analyzer, respectively. The comparison of their 1O2 emission spectra indicated that: (1) in term of the efficiency for 1O2 production, the gas-liquid-solid reaction path (in which Cl2 or HCl and H2O reacted with the solid inorganic peroxides suspension in CCl4) was prior to the gas-solid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides suspension in CCl4), but was inferior to the gas-liquid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides solution in H2O or D2O); (2) the alkali metal peroxides (such as Li2O2 and Na2O2) was prior to the alkaline earth metal peroxides (such as SrO2 and BaO2) as the solid reactants, and Cl2 was favorable than HCl as the gas reactant in efficiency for 1O2 production in these reaction paths.

Numerical analysis of the formation mechanism and suppression method of the reverse flow in a semi-open centrifugal pump

Like Wang,Jinling Lu,Weili Liao,Wei Wang,Jianjun Feng,Yaping Zhao 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.9

Reverse flow has a detrimental effect on the stable and safe operation of centrifugal pumps. To study the formation mechanism and suppression of the reverse flow, a semi-open centrifugal pump with circumferential groove in the shroud was simulated. Then, the flow field and pressure fluctuation were analysed. The absolute flow angle at the blade inlet nearing the shroud was close to 180° because of the joint action of the leakage flow and blade inlet impact under low flow rate. This phenomenon resulted in the formation of a low-speed region and the reverse flow and low-frequency pressure fluctuation. The circumferential groove provided a channel for the leakage flow, which could quickly pass through the groove, and reduced the absolute flow angle at the blade inlet nearing the shroud and weakened the trend of the tip leakage flow to upstream. The low-frequency pressure pulsation was eliminated, and the amplitude of the blade passing frequency was reduced under 0.7 Q d (Q d is the design flow rate). The reverse flow thickness coefficient became zero with the circumferential groove. The proportion of the reverse flow volume to the volume of inlet pipe decreased from 14.7 % to 2.2 % under 0.4 Q d . This research indicated that the circumferential groove arranged in the shroud could effectively suppress or eliminate reverse flow.

Welding Performance of Low-Yield-Strength Steel Shear Panel Dampers Under Large Plastic Deformation

Chaofeng Zhang,Shixi Chen,Junhua Zhao,Xuchuan Lin,Lingxin Zhang,Jiajia Zhu,Weili Wang 한국강구조학회 2021 International Journal of Steel Structures Vol.21 No.6

Characterized by large plastic deformation and energy-dissipation capacity, low-yield-strength steel shear panel dampers (LYSPDs) are widely used as energy-dissipating members in seismic engineering. However, the eff ect of welding on the properties of LYSPDs remains unclear. Hence, in this study, we investigated the matching performance between low-yieldstrength steel (LYS) and two diff erent welding materials. Subsequently, the quality of welding between LYS and dissimilar metals was investigated. Furthermore, the fracture characteristics of the welding seam of LYS under large plastic deformation were explored. Finally, the welding performance of LYSPDs under large plastic deformation was verifi ed under cyclic loading. The results of this study are signifi cant in terms of the eff ect of welding on the properties of LYSPDs.