• Journal of Electrochemical Science and Technology
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• v.10 no.4
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• pp.373-380
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• 2019

In this paper, we report the preparation of a flexible, self-standing and binder-free carbon nanotubes (CNTs) electrode with an electro-generated current collector. The copper current collector layer was electrodeposited on the backside of CNTs self-standing film obtained by a simple filtration process. The obtained CNTs-Cu assembly was used as a negative electrode in Li-ion batteries exhibiting good performance along with proving its applicability in flexible batteries.

• Journal of the Korean Society of Safety
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• v.29 no.6
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• pp.49-54
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• 2014

Electrostatic eliminators are essential in various areas of manufacturing industries to protect electrostatic hazards and to reduce inferior products. For ion sources used in the charge neutralizers, there are corona discharge, soft X-ray, and ultraviolet and glow discharge. Among them, corona discharge is generally used, because the corona discharge can easily and economically produce positive and negative ions including electrons in air at atmospheric pressure. But it is necessary to equip explosion-protection electrostatic eliminators wherever hazardous atmosphere. The electrostatic eliminators and their testing method of explosion-protection type have been developed in this research. The contents and scope of the research as follows; developing the type 'Ex s IIB T4' electrostatic eliminator of explosion-protection; developing the type 'Ex s d IIB T4' electrostatic eliminator of explosion-protection; developing the explosion-protection performance testing method of electrostatic eliminator for using AC power source.

• Microbiology and Biotechnology Letters
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• v.22 no.1
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• pp.52-58
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• 1994

The induced antibiotic peptides were isolatde from the white-spotted folwer chafer, Protaetia brevitarsis by injection of E. coli suspension to the larvae of the insect. The antibacterial activity of the peptides were assayed by the plate growth ingibition method, and were purified by ion-exchange chromatography, reversed-phase HPLC, ion-exchange HPLC and SDS-PAGE etc. The peptides were estimated as 9 kDa in molecular weight and named Protaecin I and Protaecin II, respectively. Protaecin I and II have strong antibacterial activities against Gram-positivie and/or Gram-negative bacteria, and they are stable in the heat treatment and in the range of pH 2-12.

• Journal of Astronomy and Space Sciences
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• v.6 no.2
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• pp.75-89
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• 1989

The Spacelab 1 data represented the first multiband spectral measuremets of the ${N_2}^{+}$ first negative ion bands system in the thermospheric dayglow, and the first opportunity to make a detailed comparison of the vibrational and rotational distributions over bands out to v'=5. The main purpose of this study was to decuced the excitation processes of ${N_2}^{+}$(1N) bands by determining vibrational population distributions for the upper states of ${N_2}^{+}$(1N). The vibrational population distributions to achieve a best fit to the measured Spacelab 1 data were summarized and also compared with those theoretically derived.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.664-672
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• 2011

A series of hydrophilic chromophores was synthesized through introduction of dendritic sulfonate anions using click chemistry. A dendron structure bearing several sulfonate groups enhances hydrophilicity of attached chromophores. A click triazole formation connects chromophores with hydrophilic groups. A neutral trichloroethyl sulfonate has versatile features such as easy introduction, chemical endurance for isolation or storage, and convenient transformation to a hydrophilic anion. Zinc and OH mediated cleavage of trichloroethyl group from the neutral sulfonate undergoes to generate a water-soluble sulfonate anion. The solubility was examined with different counter cations and in different pH media and thus increased with the number of attached sulfonate ion. Two hydrophilic chromophores of stilbene-derived and azobenzene-derived dipolar structures exhibit clear negative and positive solvatochromism in protic solvents, respectively.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2553-2556
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• 2010

On the basis of a simple modified Poisson-Boltzmann (SMPB) theory, taking into account the finite ionic size, the analytic expression for the effect of ionic size on the diffuse layer potential drop at negative charge densities has been given for the simple 1:1 electrolyte. It is shown that the potential drop across the diffuse layer depends on the size of the ions in the electrolyte. For a given electrolyte concentration and electrode charge density, the diffuse layer potential drop in a small ion system is smaller than that in a large ion system. It is also displayed that the diffuse layer potential drop is always less than the value of the Gouy-Chapman (GC) theory, and the deviation increases as the electrode charge density increases for a given electrolyte concentration. These theoretical results are consistent with the results of the Monte-Carlo simulation [Fawcett and Smagala, Electrochimica Acta 53, 5136 (2008)], which indicates the importance of including steric effects in modeling diffuse layer properties.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.4
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• pp.318-323
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• 2004

When a strong electric field is applied between a sharply curved electrode and a blunt surface, the corona may result in a gas movement in the electrode gap which is directed toward the blunt surface. That is called the corona wind. It enhances heat and mass transfer between the surface and the surrounding gas. Moreover such enhancement causes no noise or vibration, which can be applied in complex, isolated geometries, and allows simple control of surface temperatures. This paper examines the relationship between the corona wind and the relative humidity. The facility consists of high voltage power supply thin tungsten wire, plate electrode, multimeter, microammeter and flow meter. Gas velocity is a linear function of voltage, relative humidity and is proportional to the square root of the current. The maximum velocities for the positive and negative corona discharge are 1.9 m/s (2.74 CMM/m), 1.5 m/s(2.15 CMM/m), respectively.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.3
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• pp.143-151
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• 1995

The electrochemical impulse oscillations of the cathodic currents at the platinum group (Pt, Pd) electrode/(0.05M KHC$_{8}H_{4}O_{4}$) buffer solution interfaces have been studied using voltammetric, chronoamperometric, and electrochemical impedance methods. The periodic impulses of the cathodic currents are the activation controlled currents due to the hydrogen evolution reaction, and depend on the fractional surface coverage of the adsorbed hydrogen intermediate and potential. The oscillatory mechanism of the cathodic current impulses is connected with the unstable steady state of negative differential resistance. The widths and periods of the cathodic current impulses are 4ms or 5ms and 152.5ms or 305ms, respectively. The H$^{+}$ discharge reaction step is 38 or 61 times faster thatn the recombination reaction steps and the H$^{+}$ mass transport processes. The atom-atom recombination reaction step is twice faster thatn the atom-ion recombination reaction step. The two kinds of active sites corresponding to the atom-atom and atom-ion recombination reaction steps exist on the platinum group electrode surfaces.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.229-230
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• 2003

In these days, it is actively investigated to use loess in textile industry. The loess have been reported for emissivity of far-infrared and negative ion, and antibacterial efficacy. The loess consist of quartz, feldspar, clay mineral, iron oxide mineral, gibbsite [Al(OH)$_3$], etc. The main component of loess is clay minerals which have great adsorption about ion exchange and far-infrared emission properties. Recently, various inner-wears, sheets, and interior goods are manufactured using the loess due to its improved blood circulation, metabolism, antibacterial and deodorizing properties. (omitted)

• The Transactions of the Korean Institute of Electrical Engineers
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• v.33 no.3
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• pp.106-111
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• 1984

Prebreakdown current pulses arising from avalanche growth in SF6 were recorded under static uniform field at pressures up to about 400kpa. At pressures less than 100kpa the current pulses consist of the electron component observed as the fast rise of current, the negative ioncomponent which is superimposed, and the positive ion component comprising the tail of the pulse. The values of positive ion drift velocity were measured from the present pulse data. At pressures in excess of about 100 Kpa the pulse shapes becam distorted such that quantitative analysis was no longer possible, and did not indicate the action of any photosecondary process at the cathode. Breakdown appers to result from the seperate development of single avalanche.