• Journal of the Korean Chemical Society
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• v.23 no.6
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• pp.392-395
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• 1979

Some alkyl or aryl halides, such as ethyl bromide, butyl chloride, phenyl bromide and benzyl chloride, were reacted by Grignard's method with anhydrous tin tetrachloride in hydrocarbon media. When small amounts of ether were added into the Grignard reaction step, the reaction proceeded rather smoothly and gave good yields of corresponding organotin compounds.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.6
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• pp.837-848
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• 2006

This paper presents the test results of biological aerated filtration(BAF) process to replace activated sludge process by enhancing treated effluent quality and reducing the costs. In BAF process both BOD and SS compounds in wastewater are degraded and removed by biological reaction and filtration. Upflow BAF with expanded polypropylene media and downflow BAF with ceramic media were used to investigate the effects of hydraulic and organic loads on effluent quality. As a result, in BAF processes which has different media, upflow BAF reactor shows 5% higher efficiency than downflow BAF and this phenomena caused by backwashing methods and operational conditions. The results of influence factors analyzed by Factor Analysis Method in BOD and SS treatment efficiency are the size of media, hight of media bed and type of media. The quantitative effects of media size are 5.73% in TBOD, 5.78% in SBOD and 7.65% in TSS, so we confirmed the main factor is media size.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.82-85
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• 2004

Microinterface of W/Omicroemulsion prepared by phosphatidylcholine was used as reaction media of hydrolysis of phosphatidylcholine by phospholipaseA$_2$. Phosphatidylcholine was used as an amphiphile and was acted as a substrate. Organic phase of W/Omicroemulsion in this study was prepared by mixed organic solvents i.e. 2,2,4-trimethylpentane (isooctane) as a main solvent and 1-butanol as a co-solvent. The effect of added 1-butanol was remarkable not only on reaction beginning but also on high reaction rate. The hydrolysis reaction was dramatically initiated when 1-butanol was injected into the running isooctane/PC system. The enhancement by 1-butanol addition into single organic solvent was our original finding compare with previous conventional organic solvent. The reaction rate was elevated by the added amount of 1-butanol. The enhanced reaction rate was about 150-folds. This enhancement was speculated as 1-butanol adsorption on the microinterface. The adsorbed 1-butanol improved the properties of microinterface, especially its mobility was increased by difference of the chain length between phosphatidylcholine and 1-butanol. PhospholipaseA$_2$ molecules were located on the microinterface due to modified mobility of microinterface. Located phospholipaseA$_2$ on the microinterface reacted easily with phosphatidylcholine molecule. As a result high reaction rate was obtained. Microinterfacial properties were successfully improved by adsorbed 1-butanol molecule, and were favorable to appear higher reactivity of phospholipaseA$_2$.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.325-327
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• 2013

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3544-3550
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• 2012

Cetrizine dihydrochloride (CTZH) is widely used as an anti-allergic drug. Sodium N-bromo-p-toluenesulfonamide or bromamine-T (BAT) is the bromine analogue of chloramine-T (CAT) and is found to be a better oxidizing agent than CAT. In the present research, the kinetics of oxidation of CTZH with BAT in acid and alkaline media was studied at 313 K. The experimental rate laws obtained are: -d[BAT]/dt=$k[BAT][CTZH]^{0.80}[H^+]^{-0.48}$ in acid medium and -d[BAT]/dt=$k[BAT][CTZH]^{0.48}[OH^-]^{0.52}[PTS]^{-0.40}$ in alkaline medium where PTS is p-toluenesulfonamide. Activation parameters and reaction constants were evaluated. The solvent isotope effect was studied using $D_2O$. The dielectric effect is positive. The stoichiometry of the reaction was found to be 1:1 and the oxidation products were identified as 4-chlorobenzophenone and (2-piperazin-1-yl-ethoxy)-acetic acid in both media. The rate of oxidation of CTZH is faster in acid medium. Suitable mechanisms and related rate laws have been worked out.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.244.2-244.2
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• 2011

We introduce a novel and robust method for the preparation of nanocomposite multilayers, which allows the excellent photoluminescent (PL) properties as well as the accurate control over the composition and dimensions of multilayers. By exchanging the oleic acid stabilizers of CdSe@ZnS quantum dots (QDs) synthesized in organic solvent with 2-bromo-2-methylpropionic acid (BMPA) in the same solvent, these nanoparticles were be alternately deposited by nucleophilic substitution reaction with highly branched poly(amidoamine) dendrimer (PAMA) through layer-by-layer (LbL) assembly process. Our approach does not need to be transformed into the water-dispersible nanoparticles with electrostatic or hydrogen-bonding groups, which can deteriorate their inherent properties, for the built-up of multilayers. The nanocomposite multilayers including QDs exhibited the strong PL properties achieving densely packed surface coverage as well as long-term PL stability under atmospheric conditions in comparison with those of conventional LbL multilayers based on electrostatic interaction. Furthermore, we demonstrate that the flexible multilayer films with optical properties can be easily prepared using nucleophilic substitution reaction between bromo and amino groups in organic media. This robust and tailored method opens a new route for the design of functional film devices based on nanocomposite multilayers.

• Journal of the Korean Home Economics Association
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• v.42 no.3
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• pp.159-178
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• 2004

The purpose of this study was to investigate the effect of sexual messages in the media on adolescents' attitudes and behaviors toward sex. Subjects of this study consisted of 488 high school students in Cheong-ju City. The findings of this study were as follows; First, sexual messages in the media influenced-adolescents' attitudes toward sex. The more exposure to sexual messages adolescents had more liberal and permissive attitude toward sex. Secondly, sexual messages in the media also effected adolescents' behaviors toward sex, as well. The less sexual messages that they were exposed to, they displayed less sexual relations and behavior. In particular, the number of sexual materials in mass media, variety of sexual messages, and types of school were significant factors in predicting adolescents' sexual intercourse. The research suggested that sexual messages in the media definitely had an effect on adolescents' attitudes and behaviors toward sex. Therefore, it should be encouraged to take advantage of the television V chip and screening software for computers to reduce inappropriate access for adolescents.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.2
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• pp.17-24
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• 2012

Tetrahydrotricyclopentadiene(below THTCPD) isomer is a good candidate materials for the high performance liquid fuel component because of its high density and heat of combustion value. The object of this study was to find out the proper reaction condition to improve the fluidity of THTCPD which is solid state at room temperature. Therefore, we have carried out isomerization reactions using aluminum chloride in the varying reaction condition such as reaction temperature and solvents. The results showed that when using aluminum chloride catalyst, THTCPD isomerization reaction was more active in the polar halogenated reaction media such as dichloromethane(methylene chloride: MC), 1,2-dichloroethane(ethylene chloride: EC) and chloroform than in non-polar hydrocarbon media such as n-Hexnae and toluene and was effected by reaction temperature variation.

• Bulletin of the Korean Chemical Society
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• v.21 no.9
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• pp.901-904
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• 2000

The mechanism for the photo-Fries rearrangement of phenyl acetate andbiphenylyl acetates were reinvestigat-ed in phenol (or phenol derivatives) containing media. The results showed that the phenol (or phenol deriva-tives) which is the most common by-product of Fries reaction reacts with acyl radical togive Fries-product. These phenol (or phenol derivatives) contributions to the Fries-products were suggested as the Trivial mecha-nism for the photo-Fries reaction.

• Polymer(Korea)
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• v.32 no.4
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• pp.295-304
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• 2008

This study examined the oxidative polycondensation reaction of 2-[(pyridin-4-yl-) methyleneamino] pyridine-3-ol (2-PMAP) using air $O_2$ and NaOCl oxidants at various temperatures and times in aqueous alkaline and acidic media. Under these reactions, the optimum reaction conditions using air $O_2$ and NaOCl oxidants were determined for 2-PMAP. The number-average molecular weight ($M_n$), weight average molecular weight ($M_w$), and polydispersity index (PDI) values of O-2-PMAP synthesized in aqueous alkaline media were found to be 960, 1230, and $1.281\;g\;mol^{-1}$ using NaOCl, and 1030, 1520, and $1.476\;g\;mol^{-1}$ using air $O_2$, respectively. At the optimum reaction conditions, the yield of O-2-PMAP in aqueous alkaline media was 92.50% and 85.70% for air $O_2$ and NaOCl oxidants, respectively. The yield of O-2-PMAP in aqueous acidic media was 88.5% and 88.0% for NaOCl and air $O_2$ oxidants, respectively. O-2-PMAP was characterized by $^1H-$, $^{13}C$-NMR, FT-IR, UV-vis, SEC, and elemental analysis. TGA-DTA analysis revealed O-2-PMAP and its oligomer metal complex compounds, such as $Co^{+2}$, $Ni^{+2}$, and $Cu^{+2}$, to be stable against thermal decomposition and their weight losses at $1000^{\circ}C$ were found to be 73.0, 58.0, 53.5%, and 50.0%, respectively. In addition, the antimicrobial activities of the monomer and oligomer were tested against E. Coli (ATCC 25922), E. Faecelis (ATCC 29212), P. Auroginasa (ATCC 27853), and S. Aureus (ATCC 25923).