• 제목/요약/키워드: induction period

검색결과 559건 처리시간 0.033초

일부 아미노산이 Linoleic acid의 산화반응에 미치는 영향 (Effect of Amino acids on the Oxidation of Linoleic acid)

  • 이준호;이은희
    • 한국식품영양과학회지
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    • 제12권4호
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    • pp.336-341
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    • 1983
  • 본(本) 연구는 linoleic acid emulsion에 아미노산용액을 첨가했을 경우 이들 아미노산에 항산화효과가 존재하는지를 알아보고 만약 항산화효과가 있다면 산화기간 중 어느 단계에 영향을 미치는지 알아보고자 하였다. Linoleic acid emulsion과 $10^{-2}M$, $10^{-3}M$, $10^{-4}M$의 glutamic acid, phenylalanine, alanine용액을 부피비(比)로 동량(同量) 섞어 시료를 준비하였으며 아미노산 용액 대신 증류수를 넣은 control group과 함께 $60{\pm}1^{\circ}C$에서 incubation 시켰다. Incubation 시킨 sample은 UV visible spectrophotometer에 의해 흡광도를 측정하여 diene conjugation의 정도와 TBA 값을 정하였으며 이 값으로 induction period와 그후의 산화정도를 알아보았다. 그 결과는 다음과 같다. 1) Diene conjugation의 측정결과(測定結果) glutamic acid의 첨가는 induction period를 감소시켜 prooxidant로 작용하며 alanine과 phenylalanine은 induction period를 연장시켜 주므로 항산화효과가 있다고 할 수 있다. 2) Induction period 중 아미노산이 항산화적인 작용을 하는데에는 최적농도(濃度)가 필요하며 alanine과 phenylalanine의 최적농도(濃度)는 각각 $10^{-3}M$$10^{-2}M$이었다. 3) Induction period 측정 이후에 TBA값의 측정(測定)결과 glutamic acid, alanine, phenylalanine을 첨가한 group이 control group에 비해 그 값이 낮으므로 induction period 이후의 단계에서 항산화효과(抗酸化效果)가 있음을 알 수 있다. 이때 항산화적(抗酸化的)인 작용(作用)을 하는 최적 농도(濃度)가 glutamic acid의 경우 $10^{-2}M$이었으며 alanine과 phenylalanine의 경우에는 각각 $10^{-3}M$이었다.

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Photoperiodic Floral Induction in Pharbitis Cotyledons Affected by Polyamines and Ethylene

  • Jueson Maeng
    • Journal of Plant Biology
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    • 제38권3호
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    • pp.227-234
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    • 1995
  • Exogenous putrescine of 0.5 mM or higher concentratons applied during a 16 h inductive dark period could elevate putrescine content in cotyledons of Pharbitis nil Choisy cv. Violet, a short-day plant, resulting in complete blocking of photoperiodic floral induction. Titers of putrescine, spermidine and spermine in the cotyledons were traced throughout a 16 h dark period. While non-induced cotyledons under continous light slightly increased levels of polyamines, induced tissue maintaiend its putrescine, spermidine and spermine levels as low as 66.4%, 60.9% and 84.9% of non-induced levels respecitvely. Endogenous polyamines kept at lower levels in the inductive dark period were found to upsurge by a night break treatment of 10 min light in the middle of the dark and consequently the inductive dark effect was canceled. Elevation of polyamine titers could also be induced by 100 $\mu$L/L ethylene treatment which completely suppressed floral induction. Compared to untreated cotyledons, ehtylene-treated tissues increased putrescine content by as much as 136.5% in 12 h and spermidine level by up to 130.1% in 8 h. Ethylene-treated cotyledons not only increased endogenous polyamine content but also liberate ethylene in the second half of the inductive dark period accumulating up to three to fourfold level supporting a hypothesis that ethylene-treated tissues are stimulated to produce ethylene which in turn accelerates polyamine biosynthesis in the tissues. It is postulated that substantially low polyamine titers in the inductive dark period would be one of the necessary factors controlling photoperiodic induction of flowering in Pharbitis nil and the inhibitory effects of night break and exogenous ethylene treatment may be atributed to their action to stimulate endogenous polyamine production.

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활성탄의 자연발화에 있어서 발화유도시간과 온도분포에 관한 연구 (A Study on the Ignition Induction Time and Temperature Distribution at Spontaneous Ignition of Activated Carbon)

  • 최재욱;김상렬;이상록;최광재
    • 한국안전학회지
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    • 제8권3호
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    • pp.44-49
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    • 1993
  • The spontaneous ignition induction time and temperature distribution were observed by performing experiments for granulated activated carbon. As the results of the experiments at the same amplitude, the critical spontaneous ignition temperature was decreased with increase of the time period, while, the ignition induction time was increased with the increase of the time period. The critical spontaneous ignition temperature was decreased with the increase of the amplitude for the shorter period. The temperature distribution of the sample showed the highest around ignition-point at center of the vessel and after ignition the highest temperature was moved toward surface of the vessel.

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A investigation on the responses of conductive structures of Korean Peninsula using EM modeling

  • Yang, Jun-Mo;Oh, Seok-Hoon;Lee, Duk-Kee;Kwon, Byung-Doo;Youn, Yong-Hoon
    • 한국지구과학회:학술대회논문집
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    • 한국지구과학회 2004년도 춘계학술발표회 논문집
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    • pp.52-57
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    • 2004
  • Korean Peninsula located between Japan and China where earthquakes frequently occur, have little geophysical observation despite its tectonic importance. This study suggests the inland conductive structures inferred from GDS data measured in Korean Peninsula and try to interpret induction arrows quantitatively with the aid of 2- and 3-D geomagnetic induction modeling. Ogcheon Belt (OCB) and Imjin River Belt (IRB) are regarded as main conductive structures in Korea Peninsula, the induction arrows for the period of 60 minutes show very weak anomaly due to sea effect, which is supported by the results of 3-modeling also. However, for the period of 10 minutes, induction arrows at YIN and ICHN show anomalous patterns considered as the effect of IRB in spite of sea effect. The results of 2-D modeling which simplify geological situations provide overall information on IRB

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유도전동기의 직접토크제어 시스템에서 출력전압벡터선정을 위한 시간지연의 보상 (Time Delay Compensation for Output Voltage Vector Selection in Direct Torque Control of Induction Machine)

  • 최병태;박철우;권우현
    • 제어로봇시스템학회논문지
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    • 제9권8호
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    • pp.632-639
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    • 2003
  • This paper proposes a simple compensation scheme for the time delay caused by measurement, calculation and selection of voltage vector in Direct Torque Control (DTC) of an induction motor. In general scheme, it is difficult to know the exact delay time, furthermore the delay time can be varied by program routines for calculation and processing of measured data. In this proposed scheme, by applying voltage vector at the beginning of next sampling period, a fixed delay time is achieved and its compensation becomes much simpler. Furthermore, with the simple compensation algorithm, an improved performance can be achieved by shortening sampling period. Experimental results prove the feasibility of the proposed scheme in induction motor control.

상업용 천연 항산화제의 사용에 다른 어유의 산화 안정성 연구 (Oxidation Stability of Fish Oil Containing Commercially Available Antioxidants)

  • 장지선;이윤희;홍장환;이기택
    • 한국식품저장유통학회지
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    • 제13권1호
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    • pp.66-70
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    • 2006
  • 어유에 catechin, 로즈마리 추출물 (Antox1, Antox2, Antox3), carotene, 녹차 추출물 (Gtox) 등을 첨가하여 각각의 항산화력을 rancimat을 이용하여 측정하였으며, synergist외의 상승효과를 측정하였다. 사용된 항산화제 6종 중에서 catechin 500ppm을 첨가한 시료의 induction periods time이 4.35 hr로 control의 0.65 hr보다 3.7 hr의 차이를 보이면서 크게 나타났다. Catechin과 Antox3에 synergist인 gallic acid, EDTA, citric acid, vitamin C, ascorbic acid, propyl gallate를 사용하여 항산화 상승효과를 비교하였다. Catechin을 주 항산화제로 사용한 경우 vitamin C와 ascorbic acid의 synergist를 첨가하지 않은 control에 비해 약 1시간 이상 증가하였으며 Antox3의 경우 vitamin C와 ascorbic acid의 synergist를 첨가하였을 때 colure떼 비해 약 2시간 가량 증가함을 보였다. 그러나 전자코를 이용한 향구분 조사에 따르면, 이들 천연 항산화제를 사용하였을 때 본래의 어유취에 영향을 주는 것으로 나타났다.

토크 리플 저감을 위한 매트릭스 컨버터 구동 유도 전동기의 향상된 예측 제어 기법 (An Improved Predictive Control of an Induction Machine fed by a Matrix Converter for Torque Ripple Reduction)

  • 이은실;최우진;이교범
    • 제어로봇시스템학회논문지
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    • 제21권7호
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    • pp.662-668
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    • 2015
  • This paper presents an improved predictive control of an induction machine fed by a matrix converter using N-switching vectors as the control action during a complete sampling period of the controller. The conventional model predictive control scheme based matrix converter uses a single switching vector over the same period which introduces high torque ripple. The proposed switching scheme for a matrix converter based model predictive control of an induction machine drive selects the appropriate switching vectors for control of electromagnetic torque with small variations of the stator flux. The proposed method can reduce the ripple of the electrical variables by selecting the switching state as well as the method used in the space vector modulation techniques. Simulation results are presented to verify the effectiveness of the improved predictive control strategy for induction machine fed by a matrix converter.

1981年度 韓國動物學會 秋季學術大會 特別講演 要旨: Resistance to Carcinogens at Early Developmental Stages and the Latent Period of Induced Neoplasms

  • 근등종평
    • 한국동물학회지
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    • 제25권1호
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    • pp.29-29
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    • 1982
  • Carcinogenesis is extremely complex. Therefore, it is paradoxical but nonetheless important in cancer research if, in an animal whose parental strains are normally sensitive to cancer induction, we could find mutant strains which are resistant to various carcinogens as a result of mutations in one or two genes. No such mutants have been reported so far as I am aware but we do know that at early stages in their development, fish, mice, and humans are highly resistant to cancer induction by chemicals and radiation. I will give a brief overview of the stage-dependent resistance of fish, mice and humans to cancer induction and discuss the stem-cell mutation theory to explain the cancer-resistant stages. Finally, the latent period of induced neoplasms will be discussed in relation to the stem-cell mutation theory.

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개에서 주사 및 도입마취제로서 Propofol의 마취효과 및 심폐기능에 미치는 영향 (Anesthetic and Cardiopulmonary Effects of Propofol as Infusion and Induction Anesthesia in Dogs)

  • 유준호;이충호;김완희;남치주;권오경
    • 대한수의학회지
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    • 제42권1호
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    • pp.123-130
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    • 2002
  • To investigate the cardiopulmonary and anesthetic effects of propofol in dogs, experimental dogs were randomly divided into 4 groups (propofol infusion anesthesia, P/INF, propofol intermittent anesthesia, P/INTER, propofol induction anesthesia, P/ISO, thiopental Na induction anesthesia, T/ISO) and monitored analgesic and anesthetic effects, recovery time, body temperature, heart rate, mean arterial pressure, respiratory rate, systolic and diastolic pressure. In all groups, apnea was not observed. In the P/INF group, the respiratory rate(RR) was slightly decreased, but in the P/INTER group, RR was increased and shallowing. In the groups of P/ISO and T/ISO, the respiratory rate was decreased. Heart rate(HR) was increased after induction anesthesia in all groups, but gradually decreased. Mean arterial pressure(MAP) was decreased after injection anesthesia in the groups of P/INF and P/INTER. In the groups of P/ISO and T/ISO, however, MAP was slightly increased. Systolic and diastolic arterial pressure were gradually decreased after induction anesthesia, but not significantly. In the groups of P/INF and P/ISO, recovery time was shorter than the groups of P/INTER and T/ISO. In all groups, body temperature of animals was decreased gradually according to time but no significant changes were observed. Propofol injection doesn't make the complete loss of responses of animals, especially, in the P/INTER group. In the P/INF group, deep pain was present until the end of anesthetic period. During recovery period, any other side effects except incoordination were not monitored. The present study suggested that infusion anesthesia was superior to intermittent anesthesia as injection anesthetic agent, and propofol was better than thiopental Na as induction anesthetic agent.

저장온도에 따른 들깨기름의 산화 안전성 (Oxidative Stability of Perilla oil by Storage Temperature)

  • 백숙은
    • 동아시아식생활학회지
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    • 제4권3호
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    • pp.97-102
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    • 1994
  • The oxidative stability of perilla oil were examined by measuring peroxide value. The induction period of perilla oil for each storage temperature was measured by POV and indicated that it was 80 days for 45$^{\circ}C$, 22.5 days for 65$^{\circ}C$, 9.5 days for 85$^{\circ}C$ and 5 days for 105$^{\circ}C$ respectively. Also, the induction period of the perilla oil with different concentration of ginger powder at 85$^{\circ}C$was studied and has been found that 9.4 days for 6% ginger powder, 11.9 days for 4% and 11days for 2% ginger power. The relative antioxidant effectiveness of ginger power was 99% for 6% ginger power, 125% for 4% ginger power, 122% for 2% ginger power. The induction period of perilla oil with gingerol at 85$^{\circ}C$ was 13.5days for 2% crude gingerol, 11.7days for 0.2% crude gingerol and 12.0 days for 0.02% BHT. The elativi antroxidant effectiveness of perilla oil gingerol at 85$^{\circ}C$was 142% for 2% crude gingerol, 123% for 0.2% crude gingerol, 126% for 0.02% BHT.

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