• 제목/요약/키워드: 1,4-Addition

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율무 Yoghurt 제조에 관한 연구 II. 율무 Yoghurt의 휘발성 향미성분 및 관능적 특성 (Studies on the Manufacture of Adlay Yoghurt II. The Volatile Flavour Compounds and the Sensory Properties of Adlay Yoghurt)

  • 김상범;임종우
    • 한국축산식품학회지
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    • 제20권1호
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    • pp.64-71
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    • 2000
  • The volatile flavour compounds such as acetaldehyde, acetone, ethanol, diacetyl and acetoin were detected by gas chromatography in adlay yoghurt during fermentation and storage period at 4 $pm$1$^{circ}C$, but acetoin was trace. The contents of acetaldehyde of adlay yoghurt showed maximum immediately after fermentation and decreased significantly(P<0.05) with storage period and were in order of adlay yoghurt fermented with YC-380, ABT-D and ABT-4. The contents of acetone were shown similar trend to acetaldehyde and those of adlay yoghurt fermented with YC-380, ABT-4 and ABT-D, decreased rapidly from 6 days, 9 days and 12 days of storage, respectively. The contents of ethanol increased during the storage period and those were significant differences(p<0.05) between 6 days and 9 days of storage period in control and treatments. The contents of diacetyl were detected in control and treatments at 9 days of storage and increased slightly during the storage period. The contents of volatile flavour compounds of T1 showed similar to that of control and slightly high compared to those of treatments, and decreased gradually with increasing the level of addition of adlay in treatments. The taste, flavour and texture of T1 immediately after fermentation and during the storage period at 4$\pm$1$^{\circ}C$ were slightly higher than those of control and treatments. The scores of sensory evaluation of treatments except T1 were lowered significantly(p<0.05) with increasing level of addition of adlay. Adlay yoghurt fermented with YC-380 and ABT-4 and ABT-D were superior to both of taste and flavour, and texture, respectively. From the results mentioned above, the addition of taste and flavour, and texture, respectively. From the results mentioned above, the addition of adlay at 1% (w/v) level in skim milk substrate were suitable for quality of adlay yoghurt such as volatile flavour compounds and sensory property.

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The Stereospecific Synthesis of Abscisic Acid

  • Park, Oee-Sook;Lee, W.Y.;Park, J.C.
    • 생약학회지
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    • 제17권1호
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    • pp.67-72
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    • 1986
  • A stereospecific synthesis of 3-methyl-5-(1-hydroxy-4-oxo-2,6,6-trimethyl-2-cyclohexen-1-yl)-cis, trans-2,4-pentadienoic acid (abscisic acid) from ${\alpha}-ionone$ has been investigated. Ethyl 5-(2,6,6-trimetyl-2-cyclohexen-1-yl)-trans-4-penten-2-ynoate $({\alpha},{\beta}-acetylenic\;ester)$, which was synthesized from alpha-ionone in two steps, was stereospecifically converted in good yield into ethyl 3-methyl-5-(2,6,6-trimethyl-2-cyclohexen-1-yl)-cis, trans-2, 4-pentadienoate $({\alpha}-ionylideneacetate)$ by the conjugate addition of lithium dimethylcuprate at $-78^{\circ}C$. Basic hydrolysis of the ethyl ${\alpha}-ionylideneacetate$ gave an abscisic acid precursor, 3-methyl-5-(2,6,6-trimethyl-2-cyclohexen-1-yl)-cis, trans-2,4-pentadienoic acid, which can be oxidized to yield abscisic acid.

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PCFN-PZW계의 마이크로파 유전 특성에 미치는 Pb계 Flux의 영향 (Effect of Pb based flux on the Microwave Dielectric Properties of PCFN-PZW System)

  • 강동헌;설충의;차훈주;김영호;길상근;조봉희
    • 한국전기전자재료학회논문지
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    • 제15권12호
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    • pp.1027-1032
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    • 2002
  • (Pb$\_$0.4/Ca$\_$0.6/)(Fe$\_$1/2/Nb$\_$1/2/)O$_3$ system was modified by 10 mol% Pb(Zn$\_$1/2/W$\_$1/2/)O$_3$ addition and their sinterability and microwave properties were investigated as a function of the amount of flux (0.975PbO-0.025SnO$_2$). With increasing flux content, single perovskite phase was maintained up to 3 wt% flux addition and further addition led to the presence of Pb-rich second phase which was confirmed by EDS analysis. The apparent densities of PCFN-PZW specimen increased and showed maximum values at 2.5 wt% flux addition for the Ts=1000$^{\circ}C$ and 2.0wt% flux addition for the Ts=1050$^{\circ}C$, respectively. The dielectric constant and Q$.$f values strongly depended on the variation of density and microstructure, where the optimum values of $\varepsilon$$\_$r/ = 91.95, Q$.$f = 5938GHz, TCF = +8.15ppm/$^{\circ}C$ were obtained for the 2.5wt% flux added PCFN-PZW specimen sintered at 1000$^{\circ}C$ for 4h.

Rhizopus oryzae의 효소(酵素)에 관(關)한 연구(硏究) - 제(第)1보(報), 산성(酸性) Protease 생산(生産) 및 효소(酵素)의 특성(特性) - (Studies on the Enzyme of Rhizopus oryzae - Part I. Production of Acid Protease and Enzymatic Characteristics -)

  • 허원녕;정만재
    • Applied Biological Chemistry
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    • 제22권3호
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    • pp.135-141
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    • 1979
  • 산성(酸性) protease를 생산(生産)하는 Rhiz. oryzae의 효소생산조건(酵素生産條件)과 조효소(粗酵素)의 특성(特性)을 검토(檢討)하여 다음과 같은 결과(結果)를 얻었다. 1) 밀기울 배지(培地)에서의 최적(最適) 배양시간(培養時間)은 약(約) 48시간(時間), 최적(最適) 첨수량(添水量)은 $80{\sim}120%$이었다. 2) 밀기울 배지(培地)에 질소원(窒素源)으로서 $(NH_4)_6Mo_7O_{24},\;(NH_4)_2SO_4,\;NH_4NO_3$, casein, albumin의 첨가(添加)는 각각(各各) 효과적(效果的)이었으며 가장 우수(優秀)한 $(NH_4)_6Mo_7$. $O_{24}$와 casein의 최적첨가농도(最適添加濃度)는 각각(各各) 0.1%, 1.0%이었다. 3) 밀기울 배지(培地)에 탄소원(炭素源)으로서 glucose, galactose, maltose, lactose, soluble starch 의 첨가(添加)는 효과적(效果的)이었으며 가장 우수(優秀)한 glucose의 최적첨가농도(最適添加濃度)는 3%이었다. 4) 밀기울 배지(培地)에 인산염(燐酸鹽)으로서 $KH_2PO_4$의 첨가(添加)는 효과적(效果的)이었고 최적첨가농도(最適添加濃度)는 0.3%이었다. 5) 본효소(本酵素)의 작용최적(作用最適) pH는 2.4, 최적온도(最適溫度)는 $40^{\circ}C$부근(附近), 안정(安定) pH범위(範圍)는 $2.0{\sim}5.0$이고, $40^{\circ}C$이하(以下)에서 안정(安定)하였다. 6) 효소활성(酵素活性)은 10분(分)까지는 급격(急激)하게 증가(增加)하지만 그 이후(以後)에는 완만(緩慢)하게 증가(增加)하였다. 7) 효소액(酵素液) 2ml까지는 효소활성(酵素活性)이 급격(急激)하게 증가(增加)하였으나 그 이상(以上)에서는 거의 변화(變化)가 없었다.

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벽체구성에 따른 목조벽체 내 수분변화에 대한 연구(II) - 외기에 노출된 목조벽체의 수분이동 - (Study on Moisture Variation in Light Frame Wall with Different Wall Assemblies (II) - Moister Transfer of Light Frame Wall in Field Test -)

  • 김세종;여환명;이전제
    • Journal of the Korean Wood Science and Technology
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    • 제38권1호
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    • pp.56-65
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    • 2010
  • 본 연구는 외기에 노출된 경골목조벽체의 수분축적을 감소시킬 수 있는 벽체 구성을 찾기 위해 수행되었다. 이를 위해 다음 다섯 가지 형태의 벽체 구성을 대상으로 벽체 내 수분이동과 수분축적을 평가하였다; 일반적인 벽체구성(기본벽체 T), 실내 측 방습지 추가(P1), 실내 측과 단열재 구간의 방습지 추가(P2), 환기를 위한 사이딩 뒷면의 공기층 추가(P3), P3벽체에서 실외 측 방습지의 실내 측으로 이동(P4). 옥외 실험가옥에 기본벽체와 제안벽체를 설치하여 외기에 노출된 벽체의 수분이동과 수분축적을 평가하였다. 실험결과 계절에 따라 추가 방습지와 공기층의 개선 정도가 다르게 나타났으나 연간 벽체 내 수분축적 감소에 유리한 벽체 구성은 1) 공기층 추가 및 실내 측으로 방습지 이동(P4), 2) 실내 측 방습지 추가(P1), 3) 기본벽체(T), 4) 공기층 추가(P3), 5) 실내 측 및 단열재 구간 방습지 추가(P2) 순으로 나타났다.

Zinc-borosilicate Glass Frit 첨가에 따른 Ca(Li1/4Nb3/4)O3-CaTiO3 세라믹스의 마이크로파 유전 특성 (Microwave Dielectric Properties of Ca(Li1/4Nb3/4)O3-CaTiO3 Ceramics added with Zinc-borosilicate Glass Frit)

  • 윤상옥;김관수;조태현;심상흥;박종국
    • 한국전기전자재료학회논문지
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    • 제19권6호
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    • pp.524-530
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    • 2006
  • $xCa(Li_{1/4}Nb_{3/4})O_{3}-(1-x)CaTiO_{3}$ ceramics were sintered under the presence of zinc-borosilicate(ZBS) glass and resultant microwave dielectric properties were investigated with a view to applying the composition to low-temperature co-fired ceramic(LTCC) technology. The addition of $5{\sim}15wt%$ ZBS glass ensured successful sintering below $900\;^{\circ}C$. In general, increased addition of ZBS glass increased sinterability but it decreased the quality factor($Q{\times}f_{0}$) significantly due to the formation of an excessive liquid and second phases. As for the addition of $CaTiO_3$, the dielectric constant(${\epsilon}_r$) and temperature coefficient of resonant frequency(${\tau}_f$) increased, while the quality factor($Q{\times}f_{0}$) did not show an apparent change. The sintered $0.9Ca(Li_{1/4}Nb_{3/4})O_{3}-0.1CaTiO_{3}$ specimen at $900\;^{\circ}C$ with 10 wt% ZBS glass demonstrated 39.6 in dielectric constant(${\epsilon}_r$), 4,400 in quality factor$(Q{\times}f_{0}),\;and\;-11ppm/^{\circ}C$ in temperature coefficient of resonant frequency(${\tau}_f$).

개 정액의 보존시 glycerol 첨가 및 정장제거가 정자의 성상에 미치는 영향 (Effects of glycerol and seminal plasma in characteristics of preserved canine spermatozoa)

  • 김계성
    • 대한수의학회지
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    • 제33권2호
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    • pp.345-350
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    • 1993
  • Multiple ejaculates were collected from four male mongrel dogs. The second fraction and the small volume of third fraction from the ejaculates were divided and treated as follows : control; addition of the egg-yolk Tris extender to the semen at $37^{\circ}C$. group I; Removal of seminal plasma, group II; addition of the glycerolated extender at $4^{\circ}C$, group III Removal of seminal plasma and addition of glycerolated extender at $4^{\circ}C$. The semen cooled to $4^{\circ}C$ was equlibrated for 2hrs and preserved in refrigerator at $4^{\circ}C$. The preserved semen was evaluated for kinetics, morphology, motility and thermoresistance daily for 3 days. 1. The kinectics after preserved days 2 and 3 of group I was significantly higher than that of control(p<0.05). 2. There were no significant difference in abnormal morphology of each group between the periods of storage. 3. The motility after preserved day 1 and days 3 of group I was significantly higher than that of others(p<0.05), and the molity after preserved days 2 of group I and III was signficantly higher than that of others(p<0.05). 4. When the molity of preserved semen was measured during incubation at $37^{\circ}C$, the motility of four groups was declined at similar rates. There was no effect of removal of seminal plasma and glycerol addition on thermoresistance.

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LAS계 내열충격성 재료의 미세구조 제어(II): $Li_2O{cdot}4B_2O_3$ 프릿트 첨가가 ${\beta}$-Spodumene의 미세구조 및 열팽창특성에 미치는 영향 (A Study on the Microstructural Control of LAS Ceramics (II): Influence of L$Li_2O{cdot}4B_2O_3$ Frit Addition on the Microstructure and Thermal Expansion of ${\beta}$-Spodumene)

  • 박정현;김현민;이화선
    • 한국세라믹학회지
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    • 제29권7호
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    • pp.533-538
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    • 1992
  • Effect of Li2O.4B2O frit on the microstructural and thermal expansion behaviour of $\beta$-spodumene ceramics was investigated. With 4.0~8.0 wt.% frit addition, sintering temperature range was enlarged and densification was enhanced through liquid phase sintering. As the amount of frit addition was increased, thermal expansion coefficient was increased to 1.72$\times$10-6$^{\circ}C$-1 of its highest value, which indicated that the increment of thermal expansion coefficient due to the second phase was constrained.

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Glass 첨가 및 BaWO$_4$ 첨가에 따른 BaTiO$_3$-3TiO$_2$ 세라믹스의 고주파 유전 특성 (The effect of g1ass frit arid BaWO$_4$ Addition Microwave Dielectric Prperties of BaTiO$_3$-3TiO$_2$ Ceramics)

  • 윤중락;김지균;이헌용
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.335-338
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    • 1998
  • The effect of glass flit addition on microwave dielectric properties of BaTiO$_3$-3TiO$_2$ ceramic was studied. Addition of glass frit to this system obtained sintered sample below sintering temperature 105$0^{\circ}C$. At BaTiO$_3$-3TiO$_2$+ g1ass frit 3wt% + BaWO$_4$6 wt%m, this ceramic showed excellent microwave properties of dielectric constant 34, Q$\times$f 8,100, temperature coefficient of resonant frequency 4 ppm/$^{\circ}C$ .

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