• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1209-1212
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• 2012

In spite of many reports in the literature concerning with oxidation of benzylic alcohols to carbonyl compounds with 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) in stoichiometric amounts or even more, we surprisingly found that benzylic alcohols are directly oxidized to oximes using a catalytic amount of DDQ in the presence of hydroxylamine hydrochloride under solvent-free conditions. The present tandem catalytic method can be efficiently used for preparation of oximes in the presence of some other functional groups with excellent chemoselectivity.

• Bulletin of the Korean Chemical Society
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• v.18 no.5
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• pp.534-540
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• 1997

4H,6H-Furo[3,4-c]isoxazoles (Ⅰ-Ⅳ), potential fungicides, have been designed and synthesized via intramolecular [2+3] cycloaddition of nitroalkyne 3 as a key step. The broad spectrum of fungicidal activities of furoisoxazoles (Ⅰ-Ⅳ) were observed on plant pathogens at 250 ppm. Furoisoxazoles Ⅱ, Ⅲ with chlorophenyl at 6-position and methyl or alkylated oxime group at 3-position gave effective control of plant diseases. The furoisoxazole Ⅳ with a chlorophenyl group at 4-position also resulted in high fungicidal activities.

• Applied Chemistry for Engineering
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• v.21 no.1
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• pp.46-51
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• 2010

Polyorganosiloxane modified polyurethane (PDMS-PU) polymers were prepared from copolymerization of ${\alpha}$,${\omega}$-hydroxypropyl terminated polyorganosiloxane with isophorone diisocyanate (IPDI), polypropylene glycol (PPG), and 2,2-bis(hydroxymethyl) propionic acid (DMPA). Hydrophobic polyorganosiloxane was introduced in polyurethane main chain as soft segment block unit. The isocyanate groups in PDMS-PU block copolymer was blocked with 2-butanon oxime and obtained PDMS-PU dispersions in water by neutralizing with triethylamine (TEA). The deblocking temperature of PDMS-PU polymer was measured from thermal analysis. The good stability of the PDMS-PU dispersion was obtained by dispersing into water. PDMS-PU prepolymers were prepared with various contents of DMPA under [NCO]/[OH] = 1.12~1.53 equivalent ratio. Increasing DMPA from 7.2, 13.4, and 18.7 mole% in preparation of PDMS-PU polymer, particle sizes were decreased from 156, 100, 65 dnm. Also contact angle and adhesive strength were measured.

• Development and Reproduction
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• v.11 no.1
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• pp.21-29
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• 2007

Previously, we found progesterone receptor membrane component 2 (pgrmc2) was highly expressed in germinal vesicle (GV) stage oocytes. The present study was conducted to characterize the expression of pgrmc2, as well as pgrmc1, in the mouse gonads and embryos according to their developmental stages. We found that these membrane components were expressed in ovaries, testes, and embryos at various developmental stages in addition to oocytes. Progesterone-3-O-carboxymethyl oxime-BSA-fluorescein isothiocyanate (P4-BSA-FITC) was applied to visualize the presence of the progesterone receptor on mouse oocyte membrane, and we confirmed that immobilized progesterone is localized at surface of the oocyte. This is, at our knowledge, the first report regarding the expression of membrane component of progesterone receptor in the mouse oocytes, embryos, and gonads. The function and signal transduction pathway of progesterone receptor membrane components in oocytes requires further studies.

• Environmental Analysis Health and Toxicology
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• v.5 no.3_4
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• pp.29-36
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• 1990

Aflatoxins, produced by strains of Aspergillus flavus and Aspergillus parasiticus, can be found worldwide in corn, barley, peanuts, and other commodities. Among this group of toxins, aflatoxin B$_1$was realized to be one of the most potent environmental carcinogens, mutagens and teratogens. It is routinely monitored by methods such as thin layer chromatography, liquid chromatography, fluorodensitometric technique and radioimmunoassay. However, these assays are expensive, necessitate radioactive reagents, and require overnight incubation. In this study, the determination of fungal flora in several sorts cereals has been carried out in order to obtain an appropriate information of the population of fungi. The quantitative analysis of aflatoxin B$_1$has been carried out by High Performance Liquid Chromatography (HPLC) method and Enzyme Linked Immunosorbent Assay (ELISA). The results were summarized as follow: 1) From the 100 samples,313 colonies of fungi were isolated. Among the 313 colonies, 274 were possible to identify into 11 genera. The identified genera were Aspergillus Penicillium, Mucor, Rhizopus, Alternaria, Cladosorium, Fusarium, Circinella, Chrysosporium, Paecilomyces and Phoma. 2) Six of Aspergillus flavus were aflatoxin-producing strains. Aspergillus flavus isolated from sample barleys was contained the highest content (21.8 $\mu\textrm{g}$/ml) of aflatoxin B$_1$. 3) The yield of aflatoxin B$_1$-oxime compound was appromately 75%. Aflatoxin B$_1$-oxime-Human serum albumin was approved by formal consent as complete antigen. 4) Direct competitive ELISA permitted detection of 0.15 ng levels. In the quantitative microanalysis, ELISA was superior to HPLC method.

• Microbiology and Biotechnology Letters
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• v.20 no.2
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• pp.225-232
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• 1992

In order to develop an enzyme-linked immunosorbent assay(ELISA) for detecting aflatoxin $B_1(AFB_1)$, we produced and purified antibodies, thereafter established and evaluated methods of direct and indirect competitive ELISA. Anti-AFB, antisera, produced by immunizing rabbits with $AFB_1$-1-(0-carboxymethy1)oxime-bovine serum albumin conjugate ($AFB_1$-BSA), were removed of anti-BSA antibodies by quantitative precipitation reaction and further purified by ammonium sulfate precipitation and DEAE-Sephadex A-50 ion exchange chromatography. Purified IgG fractions were used as anti-$AFB_1$ antibodies. The antibodies, whose titer was deterrnined extremely high above $2 \times 10^6$, showed low cross-reactivity of 3~34% against $AFB_1$ analogues such as G2, B2, and GI. From the standard curves of direct and indirect competitive ELISA for AFBI, the detection ranges were found 0.2~20 and 1~10, 000 ng/ml(ppb) respectively. In their sensitivity, stability, simplicity, and rapidity, the direct method was more suitable than the indirect method for practical use.

• Journal of Adhesion and Interface
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• v.17 no.2
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• pp.67-71
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• 2016

In this study, low-viscosity polyurethane hot-melt were synthesized with polyether polyol / polyester polyol, 4,4-dicyclohexylmethane diisocyanate ($H_{12}MDI$), 2-butanone oxime (MEKO) to improve the properties and peel strength. The properties of the synthesized low-viscosity polyurethane hot-melt was evaluated through FT-IR, viscosity meter and UTM. When the content of the reactive diluent increases and the NCO-blocked prepolymer decreases, the viscosity of low-viscosity polyurethane hot-melt adhesive was increased. When the ratio of OH-terminated oligomer, NCO-blocked prepolymer and content of reactive diluent is 1 : 0.5 : 0.5, low-viscosity polyurethane hot-melt showed 1.1 kgf/cm peel strength.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1409-1414
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• 1998

To develop zearalenone-specific monoclonal antibodies, hybridoma cells were produced by fusion of myeloma cells $(P3{\times}63Ag\;V653)$ and spleen cells from BALB/c female mice immunized with zearalenone-oxime coupled to bovine serum albumin (BSA). After screening of antibody titer of them with a sandwich type enzyme-linked immunosorbent assay (ELISA), 5 hybridomas which could produced monoclonal antibodies with a high affinity for zearalenone were selected. The monoclonal antibody produced by Z-2-M26 hybridoma exhibited the high sensitivity to zearalenone and a little cross-reactivity to ${\alpha}-zearalenol$ (11%), but did not react with ${\beta}-zearalenol,\;{\alpha}-zearalenol,\;{\beta}-zearalenol$ and DON. In conclusion, the developed monoclonal antibody appeared to be a very promising immunoreagent for the future development of a specific and sensitive quantitative ELISA for zearalenone.

• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1401-1404
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• 2006

Eight structurally different acetylcholinesterase reactivators derived from currently commercially available oximes were tested for their potency to reactivate acetylcholinesterase inhibited by pesticide paraoxon (P) and DFP (D). Housefly AChE (F) and bovine red blood cell AChE (B) were used as the source of the cholinesterases. Ellman's method was taken to examine cholinesterases activity. The results show that four AChE reactivators are potent AChE reactivators, able to reach reactivation potency of more than 30% in all cases - PF, PB, DF and DB. Their reactivation potency was comparable with that of pralidoxime and even higher compared with that of HI-6, standard AChE reactivators currently available on the market.

• Environmental Analysis Health and Toxicology
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• v.17 no.2
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• pp.117-123
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• 2002

A gas chromatographic method for the determination of airborne formaldehyde was established. In order to be highly detectable with the electron capture detector, formaldehyde was derivatized to its pentafluorobenzyl oxime form by reacting with O- (2,3,4,5,6- pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) at pH of 4.6 and temperature of 50$^{\circ}C$ for 1 hour. Air samples were collected into a Tedlar$\^$(R)/ bag followed by transferring into water contained in two impingers in series. Collection efficiency in the front trap was higher than 90％. Measurement of selected indoor and outdoor air samples showed higher formaldehyde concentrations in indoor air environments and the importance of ventilation for reducing indoor pollution.