• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.335-338
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• 2000

Carbon is an attractive candidate for use in eletrochemical supercapacitors that depend on charge storage in the electrode/electrolyte international double layer. Property of an electrical double layer capacitor depend both on the technique used to prepare the electrode and on the current collector structure. The study is to research that V$_2$O$_{5}$-flyash-AC composite electrode for supercapacitor. The discharge capacitance of V$_2$O$_{5}$-flyash-AC(70wt%) in 1st and 50th cycle was 18.6F/g and 15.13F/g at current density of 0.5mA/cm$^2$. The discharge process of V$_2$O$_{5}$-flyash (3 : 97)-AC composite electrode is larger than that others.thers.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3109-3114
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• 2010

Flexible composite films of $V_2O_5$ and conductive polypyrrole ($V_2O_5$/PPy) were grown by facile electrochemical polymerization, wherein an anodization potential was applied to the substrate electrode in an electrolyte solution containing pyrrole monomer and dispersed $V_2O_5$ particles. The coating of polypyrrole (PPy) on the surface of $V_2O_5$ particles was induced by the oxidative catalytic action of $V_2O_5$ during the electrochemical polymerization of pyrrole. PPy in the composite film connects the isolated $V_2O_5$ particles. This results in the formation of conductive networks in the composite film cathode, thereby enhancing the Li+ ion diffusion to the surface of the isolated $V_2O_5$ particles and thus increasing the accessibility of the $Li^+$ ions. The specific capacity tests of the Li rechargeable batteries revealed that the discharge capacity of this composite film cathode was higher, i.e., $497\;mAhg^{-1}$, than that of $V_2O_5$/PPy powder or pristine $V_2O_5$.

• Korean Journal of Materials Research
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• v.15 no.5
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• pp.306-312
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• 2005

The hydrogen sorption properties of $Ti_{0.3}Zr_{0.2}V_{0.5}$ NEC(non-evaporable getter) alloy and its hydrides were evaluated at room temperature. The alloy and hydride powders were prepared by the Hydride-DeHydride(HDH) method. The hydrogen sorption speed of $Ti_{0.3}Zr_{0.2}V_{0.5}$ alloy was measured to increase with the amounts of hydride phase in the getter. The hydrogen sorption speeds of $Ti_{0.3}Zr_{0.2}V_{0.5},\;(Ti_{0.3}Zr_{0.2}V_{0.5})H_{1.52},\;and\;(Ti_{0.3}Zr_{0.2}V_{0.5})H_{1.94}$ were 2.22, 3.14 and 5.08 liter/sec, respectively. The unexpected enhancement of hydrogen sorption speed with the presence of the hydride phase is considered to be due to the pre-saturation of hydrogen trap sites which can retard the diffusion of hydrogen in the alloy.

• Journal of Environmental Science International
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• v.15 no.4
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• pp.333-340
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• 2006

A (5 wt.%)Mn-(1 wt.%)$V_{2}O_{5}/TiO_{2}$ catalyst were prepared by co-precipitation method and used for low-temperature selective catalytic reduction (SCR) of $NO_x$ with ammonia in the presence of oxygen. The properties of the catalysts were studied by X-ray diffraction (XRD), temperature programmed reduction (TPR) and scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDS). The experimental results showed that (5 wt.%)Mn-(1 wt.%)$V_{2}O_{5}/TiO_{2}$ catalyst yielded 81% NO conversion at temperature as low as $150^{\circ}C$ and a space velocity of $2,400\;h^{-1}$. Crystalline phase of $Mn_{2}O_3$ was present at ${\ge}\;15%$ Mn on $V_{2}O_{5}/TiO_{2}$. XRD confirmed the presence of manganese oxide ($Mn_{2}O_{3}$) at $2{\theta}=32.978^{\circ}(222)$. The XRD patterns presented of (5 wt.%)Mn-(1 wt.%)$V_{2}O_{5}/TiO_{2}$ did not show intense or sharp peaks for manganese oxides and vanadia oxides. The TPR profiles of (5 wt.%)Mn-(1 wt.%)$V_{2}O_{5}/TiO_{2}$ catalyst showed main reduction peat of a maximum at $595^{\circ}C$.

• Applied Chemistry for Engineering
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• v.5 no.2
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• pp.189-198
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• 1994

The adsorptive behaviors of carbon monoxide and methanol over $V_2O_5$catalyst were studied by means of thermal desorptlon spectroscopy (TDS) under ultrahigh vacuum conditions. Carbon monoxide adsorbed on oxygen-deficient V sites as well as on V=O groups of the $V_2O_5$ surface. CO adsorbed on the V sites desorbed at 380 K while CO adsorbed on the V=O groups formed carbonate species with surface oxygen of $V_2O_5$ and desorbed as $CO_2$ resulting in the reduction of the surface of she $V_2O_5$catalyst. The amount of CO adsorbed in the form of carbonate species increased by both the pre- and post-adsorbed oxygen. The adsorptive behavior of methanol over the catalyst was studied by thermal desorption experiments of $CH_3OH$, HCHO, CO, and $H_2$ upon methanol adsorption at 298 K. The results showed that methanol was adsorbed dissociatively on the $V_2O_5$catalyst as methoxy and hydroxyl groups at 298K.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.934-937
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• 2003

Glasses in the system $CuO-P_2O_5-V_2O_5$ were prepared by a press-quenching method on the copper plate. The glass-ceramics from these glasses were obtained by post-heat treatment, and the crystallization behavior and DC conductivities were determined. The conductivities of the glasses were range from $10^{-6}s.Cm^{-1}$ at room temperature, but the conductivities of the glass-ceramics were $10^{-3}s.Cm^{-1}$ increased by $10^3$ order. The crystalline product in the glass-ceramics was $CuV_2O_6$. Heat-treatment conditions influenced the crystal growth of $CuV_2O_6$ and conductivity. The linear relationship between in (${\sigma}T$) and $T^{-1}$ suggested that the electrical conduction in the present glass-ceramics would be due to a small polaron hopping(SPH) mechanism.

• Genomics & Informatics
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• v.19 no.4
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• pp.48.1-48.10
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• 2021

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) encodes small envelope protein (E) that plays a major role in viral assembly, release, pathogenesis, and host inflammation. Previous studies demonstrated that pyrazine ring containing amiloride analogs inhibit this protein in different types of coronavirus including SARS-CoV-1 small envelope protein E (SARS-CoV-1 E). SARS-CoV-1 E has 93.42% sequence identity with SARS-CoV-2 E and shared a conserved domain NS3/small envelope protein (NS3_envE). Amiloride analog hexamethylene amiloride (HMA) can inhibit SARS-CoV-1 E. Therefore, we performed molecular docking and dynamics simulations to explore whether amiloride analogs are effective in inhibiting SARS-CoV-2 E. To do so, SARS-CoV-1 E and SARS-CoV-2 E proteins were taken as receptors while HMA and 3-amino-5-(azepan-1-yl)-N-(diaminomethylidene)-6-pyrimidin-5-ylpyrazine-2-carboxamide (3A5NP2C) were selected as ligands. Molecular docking simulation showed higher binding affinity scores of HMA and 3A5NP2C for SARS-CoV-2 E than SARS-CoV-1 E. Moreover, HMA and 3A5NP2C engaged more amino acids in SARS-CoV-2 E. Molecular dynamics simulation for 1 ㎲ (1,000 ns) revealed that these ligands could alter the native structure of the proteins and their flexibility. Our study suggests that suitable amiloride analogs might yield a prospective drug against coronavirus disease 2019.

• Bulletin of the Korean Chemical Society
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• v.28 no.4
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• pp.581-588
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• 2007

To enhance the photodecomposition of concentrated ammonia into N2, Pt/V-TiO2 photocatalysts were prepared using solvothermal and impregnation methods. Nanometer-sized particles of 0.1, 0.5 and 1.0 mol% V-TiO2 were prepared solvothermally, and then impregnated with 1.0 wt% Pt. The X-ray diffraction (XRD) peaks assigned to V2O5 at 30.20 (010) and Pt metal at 39.80 (111) and 46.20 (200) were seen in the 1.0 wt% Pt/ 10.0 mol% V-TiO2. The particle size increased in the order: pure TiO2, V-TiO2 and Pt/V-TiO2 after thermal treatment at 500 °C, while their surface areas were in the reverse order. On X-ray photoelectron spectroscopy (XPS), the bands assigned to the Ti2p3/2 and Ti2p1/2 of Ti4+-O were seen in all the photocatalysts, and the binding energies increased in the order: TiO2 < Pt/V-TiO2 < V-TiO2. The XPS bands assigned to the V2p3/2 (517.85, 519.35, and 520.55 eV) and V2p1/2 (524.90 eV) in the V3+, V4+ and V5+ oxides appeared over V-TiO2, respectively, while the band shifted to a lower binding energy with Pt impregnation. The Pt components of Pt/ V-TiO2 were identified at 71.60, 73.80, 75.00 and 76.90 eV, which were assigned to metallic Pt 4f7/2, PtO 4f7/2, PtO2 4f7/2, and PtO 4f5/2, respectively. The UV-visible absorption band shifted closer towards the visible region of the spectrum in V-TiO2 than in pure TiO2 and; surprisingly, the Pt/V-TiO2 absorbed at all wavelengths from 200 to 800 nm. The addition of vanadium generated a new acid site in the framework of TiO2, and the medium acidic site increased with Pt impregnation. The NH3 decomposition increased with the amount of vanadium compared to pure TiO2, and was enhanced with Pt impregnation. NH3 decomposition of 100% was attained over 1.0 wt% Pt/1.0 mol% V-TiO2 after 80 min under illumination with 365 nm light, although about 10% of the ammonia was converted into undesirable NO2 and NO. Various intermediates, such as NO2, -NH2, -NH and NO, were also identified in the Fourier transform infrared (FT-IR) spectra. From the gas chromatography (GC), FT-IR and GC/mass spectroscopy (GC/MS) analyses, partially oxidized NO and NO2 were found to predominate over V-TiO2 and pure TiO2, respectively, while both molecules were reduced over Pt/V-TiO2.

• Nuclear Engineering and Technology
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• v.22 no.2
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• pp.108-115
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• 1990

The measurements of X-ray production cross-sections for 0.5~1.2-MeV proton beam are carried out on Cu and Au. For this experiment, the proton tram generated from the SNU 1.5-MV Tandem Van do Graaff accelerator is Incident on the target. The X-rays and the backscattered protons from the irradiated target are detected simultaneously by the Si(Li) X-ray detector and the SSB (Silicone Surface Barrier) charged particle detector The measured values of X-ray production cross-sections are compared with other experimental values and theoretical values such as the PWBA (Plane Wave Born Approximation) and the ECPSSR(Perturbed Stationary State corrected Energy loss, Coulomb deflection, Relativistic effects) values. For measured cross-sections near 1.0- MeV proton energy, the ECPSSR (D.D. Cohenet al., 1985) shows better agreement than the PWBA. Particularly, that of Au for 1.2 MeV proton beam is 9.69$\pm$ 0.39 barns which deviates from the ECPSSR by less than 5%. and the experimental data for 0.5~1.2- MeV proton agree with most of other experimental values within 30%.

• Journal of Food Hygiene and Safety
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• v.32 no.2
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• pp.163-169
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• 2017

The purpose of this study was to estimate the antimicrobial activity of Maesil (Japanese apricot, Prunus mume) extract against Vibrio vulnificus. The strains tested in the study were 28 V. vulnificus isolates originated from fish, seawater, mud flat and seawater in fish restaurant. The vvhA gene was detected using real-time PCR and biochemical identification expressed above good identification in 28 isolates of V. vulnificus. All of V. vulnificus used in this study was susceptible to tetracycline and chloramphenicol antibiotics. These two antibiotics were considered to be useful for the treatment of patients. Maesil extracts 2.5% and 5% showed antimicrobial activity against V. cholerae NCCP 13589 and V. parahemolyticus NCCP 11143. V. vulnificus isolate and V. vulnificus NCCP 11135 showed growth inhibition at 1.25%, 2.5% and 5% of Maesil extract, respectively. Compared with V. cholerae and V. parahemolyticus, the antibacterial activity of Maesil extract against V. vulnificus was high. The minimum bactericidal concentration of Maesil extract for V. vulnificus was 1.6%. These results revealed that Maesil extract was found to be very useful for inhibiting the growth of V. vulnificus and can be expected to prevent food poisoning caused by V. vulnificus.