• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.358-359
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• 2006

In the Langmuir-Blodgett (LB) technique, a monolayer on the water surface is transferred onto a substrate, which is raised and dipped through the surface. From this, multilayers can be obtained in which constituent molecules are periodically arranged. The LB technique has attracted considerable interest in the fabrication of electrical and electronic devices. Many researchers have investigated the electrical properties of monolayer and multiplayer films. Dendrimers represent a new class of synthetic macromolecules characterized by a regularly branched treelike structure. Multiple branching yields a large number of chain ends that distinguish dendrimers from conventional star-like polymers and microgels. The azobenzene dendrimer is one of the dendritic macromolecules that include the azo-group exhibiting a photochromic character. Due to the presence of the charge transfer element of the azo-group and its rod-shaped structure, these compounds are expected to have potential interest in electronics and ptoelectronics, especially in nonlinear optics. In the present paper, we give pressure stimulation to organic thin films and detect the induced displacement current.

• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.650-654
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• 1994

Stable polyion-complexed polymeric monolayers were prepared by spreading perfluoroalkyl monomaleate copolymers, $C_2F_8MA-VE_2$ and $C_2F_8MA-VE_3$, on a aqueous poly(allylamine) subphase. The monolayer properties have been studied by the surface pressure-area (${\pi}$-A) isotherms. The $C_2F_8MA-VE_3$ containing longer oligoethyleneglycol pendant showed more expanded monolayer phase than the $C_2F_8MA-VE_2$. The polyion-complexed monolayers were transferable on various substrates, and the resulting Langmuir-Blodgett (LB) films were characterized by FT-IR spectroscopy and scanning electron microscopy (SEM). Two-dimensional crosslinking to form a polymer network was achieved by amide formation through heat treatment under vacuum with concurrent removal of perfluoroalkyl tails. SEM observation of this film on a porous membrane filter showed that the four layer film was sufficiently stable to cover the filter pore size of 0.1 ${\mu}$m. The $C_2F_8MA-VE_3$ revealed better covering capability than the $C_2F_8MA-VE_2$. Immersion of this film in water or in benzene did not cause any change in its appearance and in Fl-IR spectra.

• Korean Journal of Environmental Agriculture
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• v.41 no.4
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• pp.276-281
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• 2022

BACKGROUND: Plastics that are used in our daily lives largely end up in the environment. In agricultural environments, plastic wastes and microplastics can be found due to the uses and improper management of plastic products (e.g., vinyl greenhouses and mulching vinyl). Microplastics can also interact with contaminants in the agricultural environment. Therefore, this study was set to investigate the sorption characteristics of tetracycline, one of widely used antibiotics, on microplastics. METHODS AND RESULTS: The sorption tests were carried out with the tetracycline solutions (0-30 mg L^-1) and microplastic films prepared from low density polyethylene (LDPE) and polyvinyl chloride (PVC). The residual tetracycline concentrations were analyzed and fitted to the Freundlich and Langmuir isotherm models. The tetracycline sorption patterns on LDPE and PVC films were described better with the Freundlich isotherm model than the Langmuir isotherm model. The isotherm model parameters suggested that the maximum sorption amount of tetracyline was greater for PVC, while the sorption affinity was greater for LDPE. CONCLUSION(S): Different types of microplastics can have different sorption characteristics of tetracycline. Therefore, there is a need for continuous research on the interaction of various types and shapes of microplastics and contaminants in the environment.

• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.121-124
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• 1990

In this paper, we study the electrical conduction mechanism in Langmuir-Blodgett(LB) ultra thin films. The LB device was a metal/LB films/metal sandwich structure, where metal is electrode. In our experiments, the temperature depend on the current at above $0^{\circ}C$. This phenomena show that the electrical conduction current is a schottky current inherent to LB ultra thin films.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1234_1235
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• 2009

The Langmuir-Blodgett (LB) method has been one of the most suitable techniques for fabricating organic thin films with well-controlled structures, compositions and thickness at the molecular level. We investigated the surface activity of dendrimer films at air-water interface by $\pi$-A isotherm. Also, we attempted to fabricate a G3-9Ph dendritic silsequioxane LB films. And their surface morphologies were observed by atomic force microscopy (AFM).

• Proceedings of the KIEE Conference
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• 1988.11a
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• pp.172-174
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• 1988

Studies and measurements of open circuit voltage in a metal/insulator/metal structure where metal are electrodes, when the insulator molecules have dipole moments all oriented parallel to each other have been reported here. The measured voltage has been shown to be directed related to the dipole moment of the molecules in the films. The insulator ultra thin films was deposited on them by the Langmuir-Blodgett technique to obtain the structure referred to as z type and Hetero structure of LB films.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.101-101
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• 1989

Multilayer films of inorganic analogues of Langmuir-Blodgett films have been prepared on silicon and gold substrates and characterized by ellipsometry, XPS, FT-IRRS, and electrochemical measurements. The deposition technique requires first covalent attachment or adsorption of a phosphonic acid anchoring agent; $HO(CH_3)(CH_2)_2Si(CH_2)_3PO_3H_2$ and $[-S(CH_2)_4PO_3H_2]_2$ were used with Si and Au, respectively. The functionalized substrates are exposed alternately to aqueous $ZrOCl_2$ and l,l0-decanediylbis(phosphonic acid) solutions to yield multilayer films. Surface-sensitive probes show that the films are compact and grow in an oriented fashion suggestive of good structural order.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1293-1294
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• 2008

The Langmuir-Blodgett (LB) method has been one of the most suitable techniques for fabricating organic thin films with well-controlled structures, compositions and thickness at the molecular level. We investigated the surface activity of dendrimer films at air-water interface by ${\pi}$-A isotherm. Also, we attempted to fabricate a 1G(4,3)-chloride dendrimer LB films. And their surface morphologies were observed by atomic force microscopy (AFM).

• Journal of the Korean Applied Science and Technology
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• v.12 no.2
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• pp.137-143
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• 1995

Octadecyltrimethylammonium-TCNQ(1:1) complex was synthesized by the reaction of LiTCNQ with octadecyltrimethylammonium bromide and the reaction product was identified with FT-IR and UV/Vis spectroscopies. In order to prepare the LB films, ${\pi}-A$ isotherm characteristics of octadecyltrimethylammonium-TCNQ(1:1) complex were investigated. The LB films of octadecyltrimethylammonium-TCNQ(1:1) complex were formed on various substrates and the formation of ultrathin films of octadecyltrimethylammonium-TCNQ(1:1) complex was confirmed by using FT-IR and UV-Vis spectroscopies.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.511-514
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• 1987

Langmuir-Blodgett (LB) films of TCNQ(tetracyanoquinodimethane) with alkyl radical($C_{12}TCNQ$) were prepared on the sample of Al/LB film/Al type where Al are electrode, and polarization in LB film and dipolar moment of molecules in the films were measured by TSC. $Al_2O_3$ layer was yielded on the electrode by natural oxidation in air. According to the cooperation of $Al_2O_3$ dielectric layer and the polarization of $C_{12}TCNQ$-LB film, the macroscopic electrical field was yielded in LB film and $Al_2O_3$ layer. The field strength in $C_{12}TCNQ$-LB films was evaluated at about $1{\times}10^6{\sim}5{\times}10^6\;V/cm$.