The effect of a-sexithiophene(α-6T) layers on the light emitting diode (LED) were studied. The α-6T was used for a buffer layer in electroluminescent (EL) devices. Enhanced carrier (hole) injection and improved emission efficiency were observed. Carrier injection characteristics were investigated as a function of α-6T later thickness. The efficiency of the electroluminescence was proportional to the thickness of α-6T layer. The highest efficiency was observed 600A of α-6T later, which was about 1.5 times higher than that of device without α-6T later. The device with a-6T showed an operation voltage lowered by 2V. The α-6T layer can substitute hole blocking layer, and control charge injection properties.

The process variables for the manufacture of translucent microemulsion prepared with 2-octyl dodecanol, 12-hydroxy stearic acid cholesteryl , POE(40)HCO and 1,3-butandiol were examined initially (primary emulsion) and following aging for three months. The techniques empolyed in this study were particle size, turbidity, interfacial tension and microfluidizer. Particle size analysis and turbidity measurement to evaluate the emulsion stability were used. It was concluded that the process of the emulsification was an important indicator of the stability of the translucent microemulsion. From the particle size and and turbidity measurement of translucent microemulsion, adding the surfactant to the oil phase before the emulsification was found to be the most important factor for the stability of emulsions. We found that interfacial tension of the adding the surfactant to the oil phase is lower than that of the adding the surfactant to aqueous phase. In spite of hydrophilic surfactant, adding the surfactant to aqueous phase produced inferior emulsion to that to oil phase.

A conductimetric study of foam formed from mixture of the protein, β-lactoglobulin, and the nonioinc surfactant, SML, revealed that their stability was reduced at concentrations of SML in the range 3~10mM. The interaction of SML with β-lactoglobulin was investigated by fluorimetry and a dissociation constant of 0.2μM was calculated for the complex. Surface tension studies confirmed the presence of interaction between the two components and provided evidence for the progressive displacement of β-lactogloblin from the air/water interface with increasing SML concentration. Experiments using air-suspended microscopic thin liquid films revealed transitions in the chainage characteristics and thickness of the film at SML concentrations below that which resulted in destabilization of the foam. However, measurements of surface mobility of fluorescent-labeled β-lactoglobulin by a photobleaching method identified that a transition to a mobile system occurred at a SML concentration which correlated with the onset of instability in the disperse phase. The results would indicate that maintenance of the viscoelastic properties of the surface is paramount importance in determining the stability of interfaces comprising mixtures of protein and surfactant.

The synthesis of N-methyl glucamine was performed in two step reaction. The first step involves the amination between methylamine and glucose in methane. The N-methyl glucamine was obtained by the reduction of using Ni catalyst under the high pressure. The second step was glucamide anionic derivatives synthesis from N-methyl glucamine, maleic anhydride, lauryl alcohol and laurylamine by Schotten Banmann reaction respectively. Their molecular structures of N-methyl glucamine and glucamide (EG-MAS and AC-MAS) were investigated by IR and 1H-NMR. Basic physical properties and biodegradability of there glucamide anionic surfactant was investigated. The range of cmc values determined by measurements of surface tention was 10-5~10-4mol/l and the surface tension of the aqueous solution revealed in the range 28~30 dyne/cm and their biodegradability was very good in the pH 5~10.

For the adsorption of polyelectrolyte at the surface of polyacrylamide gel particle, preferential adsorption of the large polyelectrolyte such as DNA is governed by the surface area of an adsorbent. The adsorption equilibrium constant can be varied by surface geometry of porous polymer, and it can be described as a function of ionic strength and surface area. Physical parameters affecting the adsorption were estimated using the theoretical governing equation of polyelectrolyte which electrophoretically moved along the column, and geometrical surface area was estimated by Waldman-Mayer's physical model. The separation of polyelectrolytes was studied using the physical parameters estimated by ionic strength and surface geometry.

A modification of the sol-gel method to obtain phase pure superconducting oxides is described. The method starts from organic salts of yttrium, barium and copper, such as acetates, and avoids the sudden and uncontrollable decomposition of the organic fraction which occurs if nitrates are used as starting materials. The aqueous solution obtained with citric acid in an alkaline medium is concentrated under vacuum. The solid so prepared is decomposed at about 300℃ thus giving an oxide precursor containing well dispersed yttrium, barium and copper. Pyrolysis at 850 - 920℃ followed by oxygen annealing gives the superconducting orthorhombic 123 phase. The results of TGA/DTA of the precursor, as well as XRD, electrical and magnetic property measurements on the pyrolysis products are presented and discussed.

There appeared enhancements of the conversion of methane by adding a small amount of CO in the aromatization reaction of methane using the Mo-zeolite catalyst. In case of adding CO2, CO2 changed to CO first, and then the conversion reaction occurred. It was observed by using isotopes as reactants that CO is related to the aromatization reaction of methane.

Excess enthalpies (HE) were measured by isothermal flow calorimetry for the nonionic amphiphile 2-butoxyethanol/water mixtures at 10 different temperatures (48.5 to 70℃) around and above the lower consolute solution temperature, Tlc. HE exhibits U-shape for the binary mixtures, and is large and negative which reflects substantial interaction between two chemical species. When the commonly used, semi-empirical Redlich-Kister (RK) polynomials were fitted to the measured HE, plots of HE vs. weight fraction provided more accurate fitting with fewer parameters than conventionally drawn HE vs. mole fraction plots. This was due to the enhanced symmetry of HE vs. weight fraction plots. Using the fitted Redlich-Kister polynomials and the Gibbs-Helmholtz relation, temperature dependence of the activity coefficients were found and compared to the values determined from vapor-liquid equilibria. The activity coefficients were in the range of one to three, indicating that the binary system deviates from ideality but not substantially. They slightly depended on temperature and the temperature effect was equivalent to 10 % change in the activity coefficients.

Transdermal therapeutic system(TTS) is often used as the method of drug dosage into the epidermic skin. Natural polymer were selected as ointment material of TTS. We investigated the permeation of natural polymer ointment containing drug in rat skin using horizontal membrane cell model. Permeation properties of materials were investigated for water-soluble drug such as oxiniacic acid in vitro. These results showed that skin permeation rate of drug across the composite was mainly dependent on the property of ointment base and drug. Proper selection of the polymeric materials which resemble and enhance properties of the delivering drug was found to be important in controlling the skin permeation rate. This result suggests a possible use of natural polymer ointment base as TTS of antihyperlipoproteinemic agent.

The tfTZ(4,4',4"-trifluoro-triazine) was used as a hole blocking material for the electroluminescent devices(ELDs) in this study. In general, the holes are outnumbered the electrons in hole transport and emitting layers because the hole transport is more efficient in most organic ELDs. The hole blocking layer are expected to control the excess holes to increase the recombination of holes and electrons and to decrease current density. The former study using the 2,4,6-triphenyl-1,3,5-triazine(TTA) as hole blocking layer showed that the TTA did not form stable films with vapor deposition technique. The tfTZ can generate stable evaporated films, moreover the fluorine group can lower the highest occupied molecular orbital(HOMO) level, which produces the energy barrier for the holes. The tfTZ has high electron affinities according to the data by the Cyclic-Voltammety(CV) method, which is developed for the measurement of HOMO and lowest occupied molecular orbital(LUMO) level of organic thin films. The lowered HOMO level is made the tfTZ to be applied for a hole blocking layer in ELDs. We fabricated multilayer ELDs with a structure of ITO/hole blocking layer(HBL)/hole transporting layer(HTL)/emitting layer/electrode. The hole blocking properties of this devices is confirmed from the lowered current density values compared with that without hole blocking layer.

Alkylation of phenol with tert-butanol in the liquid phase on mordenite was studied. The influence of many reaction parameters such as calcination temperature, reaction temperature, t-butanol/phenol molar ratio on catalytic properties was discussed. The main products were 2,4-di-t-butylphenol, o-t-butylphenol, p-t-butylphenol, the last of these was wanted product. In order to enhance the selectivity of p-t-butylphenol, optimum conditions were recommended at 500℃ calcination temperature, 140℃ reaction temperature, 1.0 molar ratio of reactants over mordenite. P-t-butylphenol was formed with 90% isomer selectivity at optimum conditions after 4hr reaction. On the basis of the behavior obtained in the cases mentioned, optimum conditions and catalytic properties for t-butylation of phenol were provided.

Surface tension as a function of concentration and temperature was measured for aquous solution of sodium N-acyl sarcosinate, RCON(CH3)CH2 COONa, From the intersection points in the (γ-logC) curves, the critical micelle concentration (cmc) was determined at 20, 30, 40, and 50℃. Structural effects on the cmc maximum and the minimum area per molecule at the aquous solution/air interface were discussed. The free energy, enthalpy, and entropy of micellization and adsorption of surfactant solution also were investigated. Numberous investigators have dealt with sodium N-acyl sarcosinates and their applications as wettings, flooding and reducing agents and as corrosion inhibitors.

Physical properties and performance characteristics of sodium salt of several pure N-acyl amino acids made from glycine, dl-alanine, sarcosine, dl-valine, l-leucine, l-aspartic acid and l-lysine seven long chain fatty acids are reported. The effect of acyl chain length and the differences in the structure of constituent amino acid of seven homologous series of amide intermediate linked carboxylate surfactant of this class on the properties are discussed.

Sodium N-acyl N-methyl taurates were synthesized by effectual acylation of fatty acid ethyl esters C(C12~C18) and N-methyl taurine. All the surface activities including krafft point, solubility, interface tension, foaming power, lime-soap dispersing ability and detergency were measured, and cmc was evaluated in dilute aqueous solution.

The oxidation of methane was carried out in six different configurations of plasma reactors in order to study the radical reactions inside and outside of the plasma zone and to explore the method to control them. Various radicals and reactive molecules, such as CH, CH2, CH3, H, and O(from O2) were generated in the plasma. A variety of products were produced through many competing reaction pathways. Among them. partial oxidation products were usually not favored, because the intermediates leading to the partial oxidation products could be oxidized further to carbon dioxides easily. It is important to control the free radical reactions in the plasma reactor by controlling the experimental conditions so that the reactions leading to the desired products are the major pathways

The VOCs(Volatile Organic Compounds) is one of the major cause for the atmosphere pollution. Breakthrough behavior of benzene and toluene in adsorption bed packed with activated carbon was experimentally studied. Composition and temperature of the gas flowing in the bed was measured and breakthrough curves for each component was obtained. Breakthrough time of benzene was earlier than that of toluene due to relatively weak adsorptivity. The relationship between breakthrough time and flow rate was obtained. The shape of temperature change with time was dependent on the position in the bed. Temperature changed faster and sharper in the inlet than in the outlet. It was noted that breakthrough behavior could be affected by the heat transfer properties.

The relative reactivities of branched and linear polycarbonates were investigated by measuring unreacted chloroformate concentration. It was found that the polymerization for the branched polymer proceeded ca. 10 times faster than that for the linear polymers. The effect of catalyst on a condensation step was studied by changing the amount of TEA (triethylamine) at t0 and t60 with keeping constant amount of TEA. The viscosity average molecular weight for the obtained branched polycarbonates were measured and compared with those of linear polycarbonates. It was found that the viscosity molecular weights of the obtained polymers decreased nonlinearly as wt % of added oligomer increased. The solution viscosities in methylenechloride for linear and branched polycarbonate increased nonlinearly as the content of polymer increased.

Cosmetic industries have recently developed sun-block products, which are composed of W/O or O/W emulsion system. It was very difficult for waterproofing product to show the stability in W/O emulsion with TiO2. To enhance the stability of W/O emulsion, it needs to be combined with the water and oil soluble components as the gelling agents. The emulsifiers used in W/O were 3.0% of cetyl dimethicone copolyol, 2.0% of sorbitan sesquioleate as the basic emulsifiers, and 0.6% of quaternium-18 bentonite and 1.5% of dextrin palmitate as stabilizer were used. The content of titanium dioxide was optimized up to 8.0%. Titanium dioxide was used as the UV scattering powder coated with Al2O3(UV-sperse T40/TN). The sunscreen cream prepared with W/O emulsion system by using QB and DP showed higher stability than that of W/O emulsion system by using each QB and DP. W/O emulsion from Formula 3 for passing one year was very durable more than F1 and F2. Within W/O emulsion by observing F1, F2 and F3 for one year, F3 was more excellent than F2 and F3 when they were observed at RT, 4℃, 40℃, because F3 used the mixed QB and DP in W/O emulsion. The zeta potential for F1, F2, and F3 after one year were 21, 30 and 43, respectively. From these result F3 was found best stable emulsion. The in-vitro SPF value for F3 was 35 for the initial product at room temperature and also, the in-vitro SPF values of F3 was 32 for after one year. Finally, the mean in-vivo SPF value of 10 volunteers for F3 was 27.3 by the Korea cosmetic association made the rules of SPF.

Organic Electroluminescent devices(OELD) consisted of multilayer structures have been studied for the application the application to flat-panel display. Metal-chelate complexes, zinc bis(2-(2-hydroxyphenyl)benzoxazolate) (Zn(BOX)2) and zinc bis(2-(2-hydroxyphenyl)benzothiazolate) (Zn(BOX)2), have been intensively investigated as an white-light emitting layer and recognized to have good electroluminescent(EL) properties. In this study, (Zn(BOX)2) and (Zn(BTZ)2) were synthesized and characterized by FT-IR, 1H-NMR, UV-VIS and PL. Their EL properties were also studied and their ionization potential(IP) and electron affinity(EA) were also measured by cyclic voltammetry(CV).

ZnxFe3-xO4(0.00.<X<0.08) was synthesized by air oxidation method for the decomposition of carbon dioxide. We investigated the characteristics of catalyst, the form of methane by gas chromatograph after decomposition of carbon dioxide and kinetic parameter. ZnxFe3-xO4(0.00.<X<0.08) was spinel type structure. The surface areas of catalysts(ZnxFe3-xO4(0.00.<X<0.08)) were 15~27 m2/g. The shape of Zn0.003Fe2.997O4 was sphere. The optimum temperature for the decomposition of carbon dioxide into carbon was 350℃. Zn0.003Fe2.997O4 showed the 85% decomposition rate of carbon dioxide and the degree of reduction by hydrogen(δ) of Zn0.003Fe2.997O4 was 0.32. At 350℃, the reaction rate constant and activation energy of Zn0.003Fe2.997O3.68 for the decomposition of carbon dioxide into carbon were 3.10 psi1-α/min and 0.98 kcal/mole respectively. After the carbon dioxide was decomposed, the carbon which was absorbed on the catalyst surface was reacted with hydrogen and it became methane.