• Title/Summary/Keyword: 1,4-Addition

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Melanogenesis Inhibitory Activities of Diarylheptanoids from Alnus hirsuta Turcz in B16 Mouse Melanoma Cell

  • Cho, Soo-Min;Kwon, Young-Min;Lee, Jae-Hee;Yon, Kyu-Hyeong;Lee, Min-Won
    • Archives of Pharmacal Research
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    • v.25 no.6
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    • pp.885-888
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    • 2002
  • Four diarylheptanoids, (5R)-1,7-bis (3,4-dihydroxyphenyl)-heptane-5-O-$\beta$-D-glucoside (1), (5R)-1,7-bis (3,4-dihydroxyphenyl)-heptane-5-ol (2), oregonin (3), hirsutanonol (4), were isolated from the bark of Alnus hirsuta Turcz and its inhibitory effects on melanogenesis by measuring the melanin level and tyrosinase activity in B16 melanoma cell were examined. Melanin level and tyrosinase activity were reduced to 75 to 85% by addition of diarylheptanoids to incubation medium of the melanoma cell. On the other hand, melanin level and tyrosinase activity were reduced to 13 to 43% by the addition of diarylheptanoids to incubation medium of the melanoma cell treated with melanogenesis stimulator, $\alpha$-MSH and forskolin. These melanogenesis inhibitory effects were significantly different compared with control.

Spontaneous Formation of Revival Waves in the 1,4-Cyclohexanedione-Bromate-Ferroin Reaction

  • Huh, Do-Sung;Kim, Young-Joon;Kim, Hye-Sook;Kang, Jong-Kon;Choe, Sang-Joon
    • Bulletin of the Korean Chemical Society
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    • v.25 no.2
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    • pp.267-270
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    • 2004
  • The bromate-1,4-cyclohexanedione-ferroin oscillating reactions are uncovered to support two types of wave activities, in which spontaneous formation of circular waves has been achieved after the disappearance of initial waves. The induction period of the revival wave is typically above 10 hours and its dependence on the initial concentrations of reactants is qualitatively different from that of initial waves. In addition to their differences in propagating speed and wavelength, the initial waves and the revival patterns have different colors, suggesting that different reaction mechanisms are involved in the formation of these spatiotemporal behaviors. Our experiments further show that the addition of hydroquinone to the reacting system can significantly shorten the induction time of the revival wave, which implicates that hydroquinone is not only a product in the bromate-1,4-cyclohexanedione-ferroin oscillating reaction but also plays a critical role in the following reactions.

Mechanism on the Formation of Bis-9,9'-thioxanthenylmethane from the Reaction of Thioxanthylium Ion With Dimethylmercury(I)

  • Kim, Sung-Hoon;Kim, Kyong-Tae
    • Bulletin of the Korean Chemical Society
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    • v.3 no.4
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    • pp.157-162
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    • 1982
  • 9-Methylenethioxanthene(6) was synthesized and for the first time good mp and spectral data were taken. Reaction of (6) with thioxanthylium ion (1) in acetonitrile led to a carbenium addition adduct (8) which then was either attacked by a variety of nucleophiles subsequently added or underwent deprotonation reaction to give an olefin (13). From these reactions, was obtained bis-9,9'-thioxanthenylmethane (2). These results indicate clearly that (2) can be formed via (8) by accepting hydride. Isolation of (2) and (6) from the reaction of (1) with 9-methylthioxanthylium ion (18) also supports the involvement of (8) in the reaction of (1) with dimethylmercury. However, addition of thioxanthene radical (4) to (6) has not been ruled out.

Dielectric Properties in the Pb1-3x/2Lax[(Mg1/3Ta2/3)0.66Zr0.34]O3 Systems

  • Kim, Yeon Jung
    • Applied Science and Convergence Technology
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    • v.26 no.4
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    • pp.70-73
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    • 2017
  • The dielectric constant and loss of poling/non-poling was measured in the $Pb_{1-3x/2}La_x[(Mg_{1/3}Ta_{2/3})_{0.66}Zr_{0.34}]O_3$ samples. The addition of $La^{3+}$ to the $Pb_{1-3x/2}La_x[(Mg_{1/3}Ta_{2/3})_{0.66}Zr_{0.34}]O_3$ did not cause a large change in grain size. But the addition of $La^{3+}$ did show transition temperature, which shifted toward low temperature in the $Pb[(Mg_{1/3}Ta_{2/3})Zr]O_3$ systems. In addition, the dielectric and pyroelectric properties (${\varepsilon}{\sim}20000$, $p{\sim}0.03C/m^2K$) of this system using $La^{3+}$ have been greatly improved. Pyroelectrics $Pb_{0.97}La_{0.02}(Mg_{1/3}Ta_{2/3})_{0.66}Zr_{0.34}]O_3$ system was found to have a relatively high ferroelectric FOMs ($F_V{\sim}0.035m^2/C$, $F_D{\sim}0.52{\times}10^{-4}Pa^{-1/2}$) at room temperature. Spontaneous polarization showed a value of $0.27{\sim}0.35C/m^2$ in the composition added to $La^{3+}$. The piezoelectric constant ($d_{33}=350{\sim}490pC/N$) and electromechanical coupling factor ($k_P=0.25{\sim}0.35$) are obtained in $Pb_{1-3x/2}La_x[(Mg_{1/3}Ta_{2/3})_{0.66}Zr_{0.34}]O_3$ compositions with $La^{3+}$ dopant.

The effect of the ammonium thiocyanate on the fermentation of the yeasts.(Saccharomyces brenerei-Hefe-Rasse XII, Saccharomyces formosensis No. 396 IAM) and Saccharomyces cerevisiae IAM) (Ammonium thiocyanate 농도가 주정효모(Saccharomyces brenerei Hefe-Rasse XII, Saccharomyces formosensis No. 396 IAM) 및 맥주효모(Saccharomyces cerevisiae IAM)의 발효작용에 미치는 영향)

  • 조운복;이상태
    • Korean Journal of Microbiology
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    • v.6 no.1
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    • pp.29-35
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    • 1968
  • There are many reports on the effect of salts to the fermentation of the yeasts, but there are a few reports on the effect of the ammonium thiocyanate(NH$_4CNS$) on the fermentation of the yeasts(Saccharomyces brenerei-Hefe-Rasse X11, Saccharomyces formosensis No. 396 IAM and Saccharomyces cerevisiae IAM). A study has been made on the effects of the ammonium thiocyanate on the fermentation of the above yeasts. The results of the research are as belows: 1) The addition of 0. 00001 mol. of ammonium thiocyanate makes the fermentation of the yeast(Sacch. formosensis No. 39 IAM) facilitate, but has not influenced the another yeast (Sacch. brenerei-Hefe-Rasse XII). 2) The addition of 0. 001 mol. of ammonium thiocyanate makes fermentation of Rases XII the fastest, but the on other yeast (Sacch. formosensis No - 396 IAM) was accelerated by the addition of 0. 1 mol., and it seems to have abnormal fermentation by the addition of 0. 0001 mol. The addition of ammonium thiocyanate(0. 00001-0. 001 mol.) inhibited the fermentatirn of the yeast(Sacch. cerevisiae IAM), but the concentration of 0. 1 mol. does not interrupt the fermentation of Sacch. cerevisiae IAM and increased the fermentation. 3) The order of effects to the fermentation of each yeast is Sacch. brenerei-Hefe-Rasse XII, Sacch. formosensis No. 396 IAM, Sacch. cerevisiae IAM.

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Studies of Low Temperature Dyeing on Silk Fiber II. Low Temperature Dyeing of Silk Fiber with the Complex Dye (견의 저온염색에 관한 연구 II. 산성 Metal Complex 염료에 있어서의 저온염색)

  • 배도규;배현석
    • Journal of Sericultural and Entomological Science
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    • v.35 no.1
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    • pp.48-51
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    • 1993
  • Using the new type auxiliary(K-1), dyeing experiment was done at the various dyeing conditions and the effects of auxiliary on the dyeing properties of metal complex dye for the silk fiber were dicussed. The exhaust rate was higher in the auxiliary 3% o.w.f. addition than sodium sulfate 50% o.w.f. The decreasing ratio of exhaust rate according to dye concentration increasing was lower at auxiliary addition than auxiliary non-addition. The exhaust rate according to increasing dyeing temperature was higher in the auxiliary addition than non-addition.

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Studies on the Effects of Some Chemicals on the Germinative Stimulatilon of Clostridiu chauvoei Spore (우기종저균(牛氣腫疽菌) 아포(芽胞)에 대(對)한 몇가지 화학제(化學劑)의 발아촉진(發芽促進) 시험(試驗))

  • Seo, Boo Kap
    • Korean Journal of Veterinary Research
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    • v.9 no.2
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    • pp.19-25
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    • 1969
  • The effects of some chemicals for the germinative stimulation of Clostridium chauvoei spore studied. The results obtained were as follows: 1. Cooked meat medium (CMM) was superior to Liver-liver bouillon (LLB) for cultivation of the organisms. 2. Heating the organisms at $70^{\circ}C$ for 30 minutes prior to cultivation in CMM stimulated the germination rate. 3. The addition of 0.5mM L-alanine to CMM was found to be most effective for the rapid germination of the spores. 4. The addition of 0.2 mM D-alanine to CMM inhibited the germination of the spores even if the spores were heat treated. 5. The addition of 0.1mM manganese retarded the germination time, but the final germination rate was greater with 0.1mM manganese than with 0.5mM L-alanine. 6. The addition of both 0.5mM L-alanine and 0.1mM manganese stimulated the germination rate to 100 per cent. 7. The germination rate was greater with the addition of germination stimulants than without any stimulants. The germination rate was approximately 6 per cent greater with prior heat treatment than without heat treatment. 8. The optimum time for the harvest of vegetative forms of the organisms was 15 hours after cultivation in the media which contain suitable germination stimulants.

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Experimental Studies on Influence of Foaming Agents on the Properties of Mortar (기포제가 모르터의 제성질에 미치는 영향에 관한 실험적 연구)

  • Sung, Chan-Yong;Hwang, Eun
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.27 no.1
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    • pp.46-61
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    • 1985
  • This study was performed to obtain the basic data which can be applied to the use of foaming mortars. The data was based on the properties of foaming mortars depending upon various mixing ratios and addings to compare those of cement mortar. The foaming agents which was used at this experiment were pre-foamed type and mix-foaming type which is being used as mortar structures. The foaming mortar, mixing ratios of cement to fine aggregate were 1:1, 1: 2, 1 : 3 and 1 : 4. The addings of foaming agents were 0.0%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5% and 3.0% of cement weight. The results obtained were summarized as follows; 1. At the mixing ratio of 1 : 1, the lowest water-cement ratios were showed by foaming mortars, respectively. But it gradually was increased in poorer mixing ratio and decreased in more addition of foaming agent. The water-cement ratios were decreased up to 1. 8~22. 0% by G, 2. 2~24. 1 % by U and 0. 7~53. 1% by J foaming mortar than cement mortar. 2, At the mixing ratio of 1 : 1, the highest bulk densities were showed by foaming mortars, respectively. But, it gradually was decreased in poorer mixing ratio and more addition of foaming agent. The bulk densities were decreased up to 1. 4~20. 7% by G, 2. 3~23. 7% by U and 26. 5~56. 5% by J foaming mortar than cement mortar. Therefore, foaming mortar could be utilized to the constructions which need low strengths. 3. At the mixing ratio of 1:1, the lowest absorption rates were showed by foaming mortars, respectively. But, it gradually was increased in poorer mixing ratio and more addition of foaming agent. Specially, according to the absorption rate when immersed in 72 hours, the absorption rates were showed up to 1. 01~1. 24 times by G, 1. 03~1. 58 times by U and 1. 10~5. 91 times by J foaming mortar than cement mortar. It was significantly higher at the early stage of immersed time than cement mortar. 4. At the mixing ratio of 1:1, the lowest air contents were showed by foaming mortars, respectively. But, it gradually was increased in poorer mixing ratio and more addition of foaming agent. Air contents were contented up to 4. 0~17. 2 times by G, 5. 2~23. 2 times by U and 23. 8~74. 5 times by J foaming mortar than cement mortar. 5. At the mixing ratio of 1 : 1, the lowest decreasing rates of strengths were showed by foaming mortars, respectively. But, it gradually was increased in poorer mixing ratio and more addition of foaming agent. Specially, the strengths of 28 days were decreased 0. 4~2. 2% than those of 7 days by foaming mortar, respectively. Also, the correlations between compressive and tensile strength, compressive and ending strength, tensile and bending strength were highly significant as a straight line shaped, respectively. 6. The correlations between absorption rate, air content, compressive strength and bulk density, absorption rate, compressive strength and air content were highly significant, respectively. The multiple regression equations of water-cement ratio, bulk density, absorption ate, air content, compressive strength, tensile strength and bending strength were computed depending on a function of mixing ratio and addition of foaming agent. It was highly significant, respectively. 7. At the mixing ratio of 1 : 1, the highest strengths were showed by cement mortar and foaming mortars, by chemical reagents. But, it gradually was decreased in poorer mixing ratio. The decreasing rates of strengths were in order of H $_2$S0 $_4$, HNO$_3$ and HCI, J,U,G foaming mortar and cement mortar. Specially, at the each mixing ratio, each chemical reagent and 3.0% of foaming agent, J foaming mortar was collapsed obviously. Therefore, for the structures requiring acid resistence, adding of foaming agent should be lower than 3.0%.

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A Clinical Study on Presbyopia in Wearing the Near Spectacle for the First Time (근용 안경을 최초 장용하는 노안에 대한 임상적 연구)

  • Yoo, Jong-Sook;Lim, Hyeon-Seon;Lee, Soo-Cheon;Hwang, Jung-Hee;Kim, Hyo-Jung
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.4
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    • pp.103-107
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    • 2008
  • Purpose: This research measured the near addition powers of presbyopia in wearing the near spectacle for the first time. Methods: We evaluated age, sex, working group, spherical power and cylindrical power and measured the power of refractive error performed the both eyes (310 eyes) of 155 subjects subjectively noncycloplegic and power of addition using the cross cylinder method. Results: There were measured the near addition powers in the range of +0.75D ~ +1.75D. In case of the average addition, they were measured with +1.06D in subjects under 43 years of age, +1.08D in 44 to 46 years, +1.23D in 47 to 49 years and +1.46D in over 50 years of age. The average age in subjects was 47.6 years old and 74 male, 81 female, 71 near sighted working group and 83 far sighted working group. Conclusions: Near addition was correlated with age, working group and cylindrical power (P<0.05, P<0.05, P<0.05).

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Fermentation Properties of Yulmoo Mulkimchi According to the Ratio of Water to Yulmoo (물비율을 달리한 열무 물김치의 발효특성)

  • 최성유;오지영;유정화;한영숙
    • Korean journal of food and cookery science
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    • v.14 no.4
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    • pp.327-332
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    • 1998
  • In the fermentation of Yulmoo Mulkimchi, various ratios of Yulmoo to water (l/l.14, l/l.5, 1/2, l/2.75, 1/4) were prepared and fermented at 4$^{\circ}C$, 15$^{\circ}C$, 25$^{\circ}C$ for up to 10 days. According to the fermentation time, the pH, acidity, total vitamin C content and microbial growth in Mulkimchi samples were determined together with sensory evaluation. Fermentation temperature on water addition ratio didn't show any difference in pH and microbial growth of Mulkimchi. However, low ratio of water resulted in high acidity and vitamin C content in Mulkimchi. In terms of acid odor and acid taste, the least water addition (l/l.4) sample was significantly strong than those of other samples. The ratio of Yulmoo to water, l/2 showed the highest overall sensorial acceptability and followed by l/l.5, l/l.4, l/2.75 and 1/4 samples. It was found that the content of vitamin C and acid taste of Mulkimchi have correlation with its acceptability.

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