• Journal of Surface Science and Engineering
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• v.37 no.2
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• pp.76-79
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• 2004

Nickel chloride coated protein chip plate was developed by using a spin coating method. The ability of histidine tagged protein adsorption was investigated at various solvents. The surface of plate has a large aggregated nickel complex with high density in water. However, the surface of plate has a very small size of aggregated nickel complex with low density in isopropanol. The ability of protein adsorption decreased as increasing the size of alkyl chain in various alcohol solvents. The mechanism on the ability of protein adsorption at the plate surface is discussed.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.6
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• pp.81-86
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• 2007

Biodiesel fuel that consists of saturated and unsaturated long-chain fatty acid alkyl esters is an alternative diesel fuel produced from vegetable oils or animal fats. However, air causes autoxidation of biodiesel fuel during storage, which can reduce fuel quality by adversely affecting its properties, such as the kinematic viscosity and acid value. One approach for improving the resistance of fatty derivatives to autoxidation is to mix them with antioxidants. This study investigated the effectiveness of five such antioxidants in mixtures with biodiesel fuels produced by three biodiesel manufacturers : tert-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), propyl gallate (PrG) and $\alpha$-tocopherol. Oxidation stability was determined using Rancimat equipment. The results show that TBHQ, BHA, and BHT were the most effective and $\alpha$-tocopherol was the least effective at increasing the oxidation stability of biodiesel. This study recommends that TBHQ and PrG be used for safeguarding biodiesel fuel from the effects of autoxidation during storage.

• Journal of the Korean Applied Science and Technology
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• v.22 no.3
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• pp.228-233
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• 2005

Langmuir-Blodgett(LB) technique can speak the best candidate of the future molecular electronic devices. But, precursor as molecular ultrathin film devices require the bulk property that are influenced by the molecular orientation. So, this device is one of current interest in molecular electronic device development of new materials. In this study, quantitative evaluation of molecular orientation in LB films of polyamic acid alkylamine salt was performed analysis experiment comparing the absorption or transmission intensity of the FT-IR spectrometer and reflection or absorption spectra with UV-visible absorption spectra. It could find that the polar angle(${\theta}$) of the dipole moment appears in about $68^{\circ}$ and the tilting angle of the alkyl chain is about $11.5^{\circ}$.

• Journal of the Korean Ceramic Society
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• v.30 no.4
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• pp.259-264
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• 1993

In this research, the organic tenside R11OSO3- with long alkyl-chain was synthesized, and the intercalationscomplexes fo montmorillonite were formed by the substitution of metallic cation in the montmorilonite by the synthesized organic tenside in following two methods, and the behaviors of the tenside R11OSO3- in the interlamellar space of montmorillonite were studied udner various conditions: 1) In order to protonize the sulfate group of R11OSO3-, the H3O-Montomorillonite, which acts as acid, was synthesized. And then, the organic tenside was intercalated in the interlamellar space of this H3O-Montomorillonite. And thus, the intercalations-complex of R11S-H3O-Montomorillonite was formed. The basal spacing obtained was about 33.84$\AA$. 2) The betaine compound R11OSO3- as a neutral molecule was direct intercalated in the interlamellar space of Na-Montmorillonite under water, and the intercalations-complexes of R11S-H2O-Montmorillonite was synthesized. In this case, the based spacing of bout 23.62$\AA$ was obtained.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.53.1-56
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• 2000

Langmuir-Blodgett(LB) technique is the best candidate for the future molecular electronic devices. But, these molecular thin film devices require the bulk properties that are influenced by the molecular orientations. So, this is of current interest in molecular electronic device fabrications of new materials. In this study, quantitative evaluation of molecular orientation in LB films of PAAS was performed by comparing the absorption intensities of the FT-IR transmission and reflection-absorption spectra and the polarized UV/visible absorption spectra. It was found that the polar angle($\theta$) of the dipole moment is about 68$^{\circ}$and the tilting angle of the alkyl chain is about $11.5^{\circ}$ .

• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1796-1800
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• 2015

Sporopollenin is a poorly characterized mixed aliphatic and aromatic polymer with ester and ether linkages. Recent studies have reported that α-pyrone polyketide compounds generated by Arabidopsis thaliana, polyketide synthase A (PKSA) and tetraketide α-pyrone reductase 1 (TKPR1), are previously unknown sporopollenin precursors. Here, the yeast Saccharomyces cerevisiae was introduced to test potential sporopollenin biosynthetic pathways in vivo. A PKSA/TKPR1 dual expressor was generated and various chain-length alkyl α-pyrones were identified by GC-MS. The growth rate of the strain containing PKSA/TKPR1 appeared normal. These results indicate that PKSA/TKPR1-expressing yeast would be a starting platform to investigate in vivo sporopollenin metabolism.

• Journal of Microbiology and Biotechnology
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• v.16 no.6
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• pp.965-968
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• 2006

Exogenous S-adenosyl-L-methionine (AdoMet) enhances the production of actinorhodin in Streptomyces coelicolor. Thirty compounds related structurally with AdoMet were tested for their actinorhodin production. The relationships between the structures of the compounds tested and their actinorhodin production were analyzed using computational methods, and the molecules containing both bulky substituents at the C6 position of adenine and the long 5'-alkyl chain of adenosine were predicted to show high actinorhodin production.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.764-767
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• 2001

Because using LB method, result that produce Arachidic acid and Stearic acid LB film and measure the accumulation characteristic and electrical characteristic is as following. Organic monolayers of surface of the water compression each 9 layer's LB film to slide glass and manufactured MIM device compressing molecular film only. Could confirm that accumulation was good seeing as absorption coefficient and SEM picture, AFM picture that prevent manufactured LB films. Formation of domain of coexistence form that prevent LB film is indefinite and distinction of border side was not clear, and could know that roughness appears greatly. Obtained current by applied voltage could know that is proportional almost, though Arachidic acid appeared as bulk of current that happen in equaler certification voltage than Stearic acid is less, this alkyl chain longer Arachidic acid that serving relations special quality is superior know can .

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.272-272
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• 2006

In recent years, water-free polymer electrolyte membranes are attracting serious attention due to the possibility of the fuel cell operation at intermediate temperatures ($100{\sim}200^{\circ}C$). It was reported that phosphonic acids have proton conductivity under anhydrous conditions and in particular, relatively high proton conductivity could be obtained from the composite materials with heterocycles such as imidazole, pyrazole, etc. In this work, styrene based polymers, poly((4-vinylbenzyloxy)alkylphosphonic acid), which have phophonic acid group at the end of alkyl chain was synthesized. These polymers were analyzed in terms of thermal stability and proton conductivity. Additionally, cyclic oligosiloxanes tethered with triazole were prepared and analyzed.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.311-311
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• 2006

The morphology of Poly(styrene-b-methylmethacrylate) (P(S-b-MMA)) block copolymer thin films deposited on silicon wafers was controlled by treating the substrates with Self-Assembled Monolayers (SAM) of phenylsilanes with different alkyl chain lengths. It was found that the treatment with SAM strongly modified the substrates properties, especillay the surface energy, as compared with bare silicon oxide. By futher adjusting the molecular weight of P(S-b-MMA), a variety of morphologies could be generated, including a perpendicular orientation of lamellea of PS and PMMA, which is required for industrial applications.