• Bulletin of the Korean Chemical Society
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• v.19 no.1
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• pp.68-74
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• 1998

The complexation of ethylammonium ion by alkyl p-tert-butylcalix[6]aryl ester derivatives was studied via measurements of proton and carbon spin-lattice relaxation times $(T_1)$ and chemical shift changes in solution state $(CDCl_3)$. The results indicate that the endo-type complexes are formed and that the overall tumbling rates of these complexes are more rapid than those of the corresponding free hosts. The association constants for these complexes in $THF-d_8$ were determined by $^1H$ NMR titration at several different temperatures to estimate the relevant thermodynamic parameters. The logK's for ethylammonium complexes of methyl, ethyl, and propyl esters at 313 K, for example, were found to be 1.56, 3.41, and 3.08, respectively. The complexes formed may be thought of as being kinetically stable in view of their $^1H$ NMR behavior in 2 : 1 host/guest solution.

• Bulletin of the Korean Chemical Society
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• v.18 no.5
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• pp.519-522
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• 1997

A series of new ligands having convergent dicarboxylic acid functions, based-upon Rebek's cleft-type ionophore, have been prepared and their ion binding properties were investigated by the competitive extraction and transport experiments. The main purpose of the modification was to increase the lipophilicity of the Rebek's ionophore, which was attempted by utilizing propyl analog of Kemp's triacid or by changing the bridging unit. Ionophores 5 and 6 were found to have a pronounced ion-binding property toward Ca2+ ion. The selectivity in competitive extraction of ionophore 5 at pH 9 for Ca2+ over Mg2+ and Sr2+ is 2.0 and 59.3, respectively. The selectivity in competitive transport of ionophore 5 for Ca2+ over Mg2+ and Sr2+ is 29.8 and 99.3, and that of ionophore 6 is 10.0 and 23.2, respectively.

• Bulletin of the Korean Chemical Society
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• v.20 no.10
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• pp.1145-1148
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• 1999

1H NMR spectra of methyl-, ethyl-, propyl-, isopropyl-, butyl-, N-methylethyl-, N-methylpropyl-, and N-methylisopropylamine coordinated to the paramagnetic 11-tungstocobalto(II)silicate anion (SiW11Co) in dimethylsulfoxide-d6 or dimethylformamide-d7 are reported. For these complexes the ligand exchange is slow on the NMR time scale and pure 1H NMR signals have been observed at room temperature. No complex is detected in D2O. From the pseudocontact shifts of the CH2 and CH3 groups in ethylamine the energy of the gauche conformers with respect to the anti conformer is estimated. Two diastereotopic protons in the CH2 group of N-methylethylamine have quite different chemical shifts especially at low temperatures (e.g. 48.5 vs. 19.4 ppm at -10℃). This may be attributed mainly to the different positions of the two protons in the most stable (gauche) conformer.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.137-141
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• 2010

Poly [4,7-Di-thiophen-2-yl-benzo(1,2,5)thiadiazole]-alt-1,4-bis(dodecyloxy)-2,5-divinylbenzene (PPVTBT) was synthesized by the Heck coupling reaction between 4,7-Di-thiophen-2-yl-benzo(1,2,5)thiadiazole and 1,4-bis(dodecyloxy)-2,5-divinylbenzene. The maximum absorption and band gap of PPVTBT were 550 nm and 1.74 eV, respectively. The HOMO and LUMO energy level of PPVTBT were -5.24 eV and -3.50 eV, respectively. The photovoltaic device based on the blend of PPVTBT and (6)-1-(3-(methoxycarbonyl)propyl)-{5}-1-phenyl[5,6]-$C_{61}$ (PCBM) (1 : 6 by weight ratio) was fabricated. The efficiency of device was 0.16%. The short circuit current density (Jsc), fill factor (FF) and open-circuit voltage (Voc) of the device was $0.74mA/cm^{2}$, 31% and 0.71 V, respectively, under AM 1.5 G and 1 sun condition ($100mA/cm^{2}$).

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.123-128
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• 2004

Effects of jeotkal (salted-fermented seafoods) addition on acid production, growth of lactic acid bacteria, sensory properties, and volatile odor components of kimchi were investigated. Changes in pH and acidity of kimchi added with myulchi-aekjeot, kanari-aekjeot, and aekche-Jukjeot were similar to, whereas those of saeu-jeot sample on 0, 2, and 4 days of ripening were slightly different, those of control sample. Changes in pH and acidity of jogae-jeot sample during whole ripening period were markedly different from those of other samples. Numbers of lactic acid bacteria of all samples on 0 and 4 days were $1.8-2.6{\times}10^{5}\;and\;1.0-2.5{\times}10^{9}\;CFU/mL$, respectively. Overall acceptability and taste of kimchi added with jeotkal except jogae-jeot were higher than those of control sample, with saeu-jeot-added kimchi showing the highest scores. Eight volatile odor components were identified in 6-day-ripened kimchi samples, and those of saeu-jeot sample were slightly higher than those of other samples. Diallyl sulfide and methyl propyl disulfide were produced in 6-day-ripened samples. Ethanol, methyl allyl sulfide, and dimethyl disulfide concentrations increased, whereas that of allyl mercaptan decreased in 6-day-ripened samples compared to unripened ones.

• Korean Journal of Food Science and Technology
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• v.15 no.2
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• pp.141-149
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• 1983

The purpose of the present work is to find out the optimal conditions for the production of filefish protein preparations and to define the functional properties of the protein products. Fish protein concentrate (FPC) and fish protein isolate (FPI) were prepared by extraction of whole or headed and gutted filefish with various organic solvents. The results of the present study are as follows; 1. Among the solvents tested iso-propyl alcohol appeared to be the most effective for the extraction of lipid and also for that trimethylamine from the fish muscle. 2. The optimal extraction time showed to be 20 minutes with ethyl iso-propyl alcohol at $65-70^{\circ}C$under adequate mixing. 3. The most effective solvent ratio to the weight of fish material was proved to be 5:1 at the first extraction and to be 2:1 at the second stage. 4. The lipid content of the protein preparations reduced to below 0.5% by the third stage of extraction of headed or gutted filefish. The protein concentrate from whole fish, however, showed the lipid content of 0.27-0.31% only after the fifth stage of extration. 5. The protein contents of the protein concentrate and the protein isolate from whole filefish were 81.08% and 87.41% and the lipid contents of the two protein preparations were 0.43% and 0.45% respectively. 6. Higher calcium content was found in the protein concentrate rather than in the protein isolate. No sodium and potassium in the protein isolate were detected while the fish concentrate appeared to contain a considerable amounts of both elements. 7. The functional properties, such as suspended solids, wetability, emulsion stability and foam viscosity of the filefish protein isolates were proved to be higher than those of the protein concentrate.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.1
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• pp.25-33
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• 2008

A selective separation of Actirlide(III) by a nPr-BTP/nitrobezene extraction system was studied. The nPr-BTP (2.6-Bis-(5.6-n-propyl-1.2.4-triazin-3-yl)-pyridine) of a environmentally -friendly CHN type was self-synthesized and its compatability with diluent and stability with nitric acid were investigated. At the 0.1M nPr-BTP/nitrobenzene-1M $HNO_3$ and O/A=2, extraction yields of Am used as a representative of Actinide(III) and Eu were about 85% and 8%, respectively, and the other RE elements such as Nd, Ce and Y were extracted less than 3% (separation factor of Am and Eu was about 60). Thus, there was no problems in the selective extraction of Actinide(III) from RE. The stripping yield of Am with 0.05M $HNO_3$ at O/A= 1, however, was about 43% and the maximum stripping yield was 65% at O/A=0.3. It is necessary to develop the stripping system including the stripping agent instead of nitric acid solution.

• Archives of Pharmacal Research
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• v.22 no.4
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• pp.384-390
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• 1999

Thirty-four glutathione conjugates of 5,8-dimethoxy-1,4-naphthoquinones (DMNQ) were synthesized and their structure was determined. The yield of GSH conjugate was dependent on size of alkyl group; the longer the size of alkyl group was, the lower was the yield. It was also found that the length of alkyl side chain influenced the chemical shift of quinonoid protons; the quinonoid protons of 2-glutathionyl DMNQ derivatives with R=H to propyl, 6.51-6.59 ppm vs. other ones with R=butyl to heptyl, 6.64-6.68 ppm. this was explained to be due to a folding effect of longer alkyl group. Glutathione (GSH) reacted with DMNQ derivative first to form a 1,4-adduct (2- or 3-glutathionyl-1,4-dihydroxy-5,8-dimethoxynaphthalenes) and then the adduct was autooxidized to 2- or 3-glutathionyl-DMNQ derivatives. Moreover, GSH reduced DMNQ derivatives to their hydrogenated products. It was suggested that such an organic reaction might play an important role for a study of metabolism or toxicity of DMNQ derivative sin the living cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.12
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• pp.1609-1614
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• 2008

To provide scientific information for processing of value-added products from onion, volatile flavor compounds were compared in onions harvested in 6 regions, such as Muan (Jeonnam), Buan (Jeonbuk), Andong (Gyeongbuk), and 3 regions of Gyeongnam around Changnyeong (Yueo, Jangma, Seongsan). A total of 51 compounds were detected in samples by solid phase microextraction (SPME)/GC/MSD and they consisted mainly of sulfur-containing compounds (20), aldehydes (4), ketones (5), esters (11), aromatic hydrocarbons (4), nitrogen containing compounds (2), and miscellaneous compounds (5). The sulfur-containing compounds were the major compounds with ranges of $62.6{\sim}80.3%$ of total volatiles, regardless of harvested regions. The amounts of 5 sulfur containing compounds known as having antioxidant activity (2,4-, 2,5-dimetylthiophene, 2-vinyl-1,3-dithiane, 5-methoxy thiazole, and 3,5-diethyl-1,2,4-trithiolane) were the highest in Andong and followed by Yueo, Jangma, Buan, Seongsan, and Muan. However, onions from Buan region had the highest amounts of 5 sulfur-containing compounds known as having anticarcinogenic activity ((Z)-, (E)-methyl propenyl disulfide, (Z)-, (E)-propenyl propyl disulfide, and di-2-propenyl disulfide), followed by Yueo, Andong, Jangma, Seongsan, and Muan.

• Food Science and Preservation
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• v.13 no.4
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• pp.483-489
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• 2006

Considering the development of fusion ingredients rom red ginseng and Cheonggukjang (soybean-fermented food), their commercial powders were evaluated in their Hunter's colors, volatile compounds, and sensory properties depending on manufacturing companies and mixing ratio of both powdered products. Hunters L, a and b values of red ginseng powders were $75.56\sim85.50,\;1.90\sim6.30,\;and\;23.29\sim35.08$, respectively, while those of Cheonggukjang powders were $64.96\sim71.69,\;4.64\sim8.30,\;and\;30.45\sim36.50$, respectively. Volatile compounds were mainly composed of hexanal, $\beta-pinene$, methyl benzene, 3,5-methyl propyl nonane, 2-propanone, decane, and 2,8-dimethyl undecane in red ginseng samples, and of 2,3-butanedione, decane, 2,2,7,7-tetramethyl octane, and 3-methyl butanal in Cheonggukjang samples. Total volatiles of the mixed samples decreased as ginseng decreased and Cheonggukjang increased. The mixed sample of both red ginseng and cheonggukjang in same amounts was the highest in its sensory acceptability, which was composed in the order of 2-propanone, 2-butanone, pentane, hexanal and 3-methyl butanal. The above results indicate that red ginseng and Cheonggukjang showed a potential as fusion ingredient for preparing new functional produce through further processing.