• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.2101-2106
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• 2009

A series of facial amphiphiles 3,7-diaminocholestane were synthesized from 3,7-diketocholestane via 2 sequential reductive aminations and anion recognition was evaluated with acetate, chloride, bromide, fluoride and phosphate anions. The stereo-selective reductive amination protocol was utilized to synthesized facial amphiphiles afforded receptors in high yields. The molecular receptor 2 showed the highest binding constant with acetate in a 1:1 ratio.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.158-161
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• 2004

Chlorinated aliphatic hydrocarbons (CAHs) especially perchlorethylene (PCE) and trichlooethylene (TCE) are common groundwater contaminants in Korea. PCE and TCE were often reductively dechiorinated in an aquifer. Several isolates dechlorinate PCE to TCE or cis-1,2 dichloroethylene (c-DCE) were obtained from contaminated and pristine sites in USA and Europe. However in Korea, no information on indigenous microorganism being involved in reductive dechlorination of PCE and TCE is available and different dechlorinating microorganisms might be reside in Korea, since geochemical, and hydrogeological conditions are different, compared to those in the other sites. So we evaluate that: 1) if reductive dechlorinating microorganisms are present in PCE-contaminated site in Korea, 2) if so, what kinds of microorganisms are present; 3) to what extent PCE is reductively dechlorinated. As a results in some PCE-contaminated aquifers in Korea other dechlorinating microorganisms but Dehalococcoides ethenogenes may be responsible for PCE dechlorination. More detailed molecular works are required to evaluate that different dechlorinating microorganisms would reside in Korea.

• 펄프종이기술
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• 제33권2호
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• pp.68-73
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• 2001

This experiment was executed to clarify the optimum condition of reductive bleaching for 100% color papers. The reductive bleaching of the color paper was desirable to be done under such conditions as high temperature over $60^{\circ}C$ and high consistency within possibly short time. The FAS bleaching like the sodium hydrosulfite required oxygen-free condition. Especially, as the mixture between pulps and chemicals was favored in case of the high consistency, it was actively recommended. Therefore, it is desirable to control the dosage with the type of the dyes, the nature, the dye content, the paper compositions, and the targeting initial and final brightness.

• 펄프종이기술
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• 제32권2호
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• pp.45-50
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• 2000

This study was to get the optimum conditions on bleaching by mixing of various colored ledgers with white ledger by 50：50 ratio. This bleaching was carried out by two steps, reductive-oxidative process was shown a better brightness compared to oxidative-reductive one. Especially, in reductive bleaching using sodium hydrosulfite, the aging temperature should keep above 6$0^{\circ}C$ irrespective of aging time, alkaline condition was more effective than acid one. Final brightness after bleaching and feinting was obtained over 78% to be used by the raw pulp of tissue.

• Asian-Australasian Journal of Animal Sciences
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• 제4권4호
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• pp.407-410
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• 1991

The relationship between the possible structural change due to chemical modifications and functionality changes was studied in pigskin collagen. Amino groups in collagen were modified by succinylation and reductive alkylation. Carboxyl groups were modified using carbodiimide. Thermal denaturation temperature of collagen increased remarkably by carboxyl groups modification whereas decreased by succinylation and reductive alkylation. Emulsifying capacity was improved by reductive alkylation and carboxyl groups modification while emulsion stability was improved by succinylation. Chemical modifications increased solubility whereas decreased the foaming capacity of collagen. Viscosity of collagen at various pH varied with methods of modification.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.33-36
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• 2006

The reductive dechlorination of chlorinated organic compounds by soil minerals in soil and groundwater were carried out in this study. FeS, green rust, and magnetite were chosen as the representative soil minerals which were capable of degrading chlorinated compound in soil system. FeS was the most effective reductant in degradation of carbon tetrachloride. The reductive degradation of CT and 1,1,1-TCA by FeS was much faster than that of 1,2-DCB and 2,4-DCP. The reactivity of FeS was effectively improved by the addition of trace metals. The addition of Co to FeS suspension enhanced the reaction rate of 1,2-DCB by a factor of 46 compared to that by FeS without Co.

• 펄프종이기술
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• 제34권3호
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• pp.38-45
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• 2002

The effect of sequential oxidative-reductive bleaching on brightening of the MOWs is investigated. The improvement in brightnesses of MOWs is more effective in conventional PFAS bleaching than in P/T bleaching. There is no difference in the mechanical properties or the bleached pulps between PFAS and P/T sequences. Considering the brightness gains and bleaching chemicals cost, for the MOW A(Initial brightness: 68.3% ISO) containing 5％ ONP and 20% colored paper, the P/T bleaching is more economical than the PFAS bleaching. However for MOW B(initial brightness: 59.1％ ISO) containing 15% ONP and 35％ colored paper, there is no difference in the bleaching efficiency between PFAS and P/T bleaching.

• Archives of Pharmacal Research
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• 제17권3호
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• pp.190-193
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• 1994

Friedel-Crafts reaction isopropoxybenzene with methyl $\alpha$-chloro-$\alpha$-(maethylthio)acetate 1 afforded methyl $\alpha$-methylthio-p-isopropoxyphenylacetate 2d, which was readily converted into methyl p-isopropoxyphenylacetate 3 by reductive desulfurization with zinc dust in acetic acid. Methylation of 3 with sodium hydride and methyl iodide gave methyl $\alpha$-(p-isopropoxyphenyl)propionate 5. Methyl p-hydroxyphenylakanoates (4,6), useful intermediates for some medicines, were easily prepared by treatment of 3 and 5 with titanium tetrachloride, respectively.

• Bulletin of the Korean Chemical Society
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• 제32권11호
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• pp.4079-4082
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• 2011

• Archives of Pharmacal Research
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• 제17권1호
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• pp.17-20
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• 1994

Friedel-Crafts reaction of fluorene with methyl ${\alpha}$-chloro-${\alpha}$-(methylthio)acetate 1 gave methyl $\alpha$-methylthio-2-fluoreneacetate 2. Cicloprofen 8, a potent antiinflammatory agent, was prepared by methylation of 2 followed by reductive desulfurization of methyl 2(2-fluorenyl)-2-(methylthio)propionate 6 and hydrolysis of methyl 2-(2-fluorenyl)propionate 7.