• Title/Summary/Keyword: retardation effect

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The Effect of TMT on Mechanical Properties of Steel & Aluminum Alloy (철강(鐵鋼) 및 알루미늄재료(材料)의 기계적(機械的) 성능(性能)에 미치는 TMT(thermomechanical treatment)의 영향)

  • So, Myoung-Gi
    • Journal of Industrial Technology
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    • v.1
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    • pp.53-60
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    • 1981
  • A study has been performed on the effect of TMT(thermomechanical treatment) on the mechanical properties of steel and aluminum alloys. Improvement of the mechanical properties on steel by HTMT is due to refinement of prior austenite grain size, martensite lath size and the distribution of fine carbide precipitates and on aluminum alloy by ITMT is due to grain size refinement, homogeneous distribution of small second phase particles and retardation of the recrystallization.

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Effect of Gibberellic Acid on the Internode Elongation of Rice Cultivars (Gibberellic Acid 처리가 수도품종의 절간신장에 미치는 영향)

  • Gyan L, Shrestha
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.25 no.1
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    • pp.20-24
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    • 1980
  • Seven different rice cultivars treated with different levels of gibberellic acid (0, 10, 50 and 100 PPM GA3) at panicle initiation stage. showed retardation effect on the panicle length and the 2nd internode from the top, where as, the total culm lengths were remarkably elongated, about 50-120% in short varieties and about 10-15% in the tall varieties over the control, mainly, because of the lower internodes elongation. The 2nd internode of Gamadi variety from Nepal was almost entirely shortened with GA3 application.

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Effect of Dietary Xylooligosaccharide on Indigestion and Retarding Effect of Bile Acid Movement Across a Dialysis Membrane (식이 Xylooligo당의 난소화성과 담즙산 흡수 지연효과)

  • 이순재;주길재;이인구;김성옥
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.4
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    • pp.705-711
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    • 1998
  • The digestibility of xylooligosaccharide(XO) by juices of the digestive tract and retardation effect of XO on the adsorption of bile acids were compared with fructooligosaccharide(FO) and isomaltooligosaccharide(IO). In vitro digestion experiments showed that any hydrolyzed products of FO, IO and XO were not detected by HPLC after reaction with saliva, pancreatic, artifical intesteinal, and large intestinal luices, and artifical sera for 4 hours at 37$^{\circ}C$. However, IO were mostly digested by the small intestinal juice, and some quantity of FO were digested. XO were not digested at all by any enzyme of digestive tract. In order to investigate retardation effect of XO on the bile acid absorption. In vitro, permeability of bile acid against dialysis membrane was determined in the mixture which contained guar gum instead of XO was set 100%. The premeability of bile acid showed about 50% in the FO and IO mixture and 43% in the XO mixture. The activity of lactase in FO group and activity of sucrase and maltase in XO group in rat small intestinal mucosa were significantly decreased. Consequently, the present results indicate that XO is indigestible in digestive tract and has retarding effect of adsorption of bile acid compared with the other oligosaccharides. The disaccharidase activity of the XO dietary group was lower than that of the other oligosaccharides dietary group. Furthermore, it was suggested that hydrolysis of sugar may be retarded in digestive tract and glucose level in blood may be controlled effectively by the XO.

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In Vitro and In Vivo Physiological Characteristics of Dietary Fiber from By-product of Aloe vera Gel Processing (알로에 베라 유래 식이섬유의 In Vitro 및 In Vivo 생리기능 특성)

  • Baek, Jin-Hong;Cha, Tae-Yang;Heo, Jin-Chul;Lee, Sang-Han;Lee, Shin-Young
    • Food Engineering Progress
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    • v.14 no.2
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    • pp.173-182
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    • 2010
  • A fiber fraction (Aloe cellulose), the by-product obtained from Aloe vera gel processing was freeze dried and investigated for in vitro glucose/ bile acid retarding effects of powdered sample (100 mesh) comparing with commercial $\alpha$-cellulose as a reference sample. We also examined the effectiveness of physiological functionality such as the antiobesity and anti-constipation on Sprague-Dawley (SD) rat. The Aloe cellulose powders during in vitro dialysis experiment for 2 hours exhibited the glucose and bile acid retarding index of 20.32-35.2% and 53.13-28.30%, respectively. Especially, freeze dried aloe cellulose showed the 2.5 and 1.2-6 times higher effect on in vitro glucose and bile acid retardation than those of $\alpha$-cellulose. These relatively good retarding effects on glucose and bile acid diffusion suggest a potential of preventing from diabetes and arteriosclerosis of some extent. Also, the results from animal experiments on SD rats fed a high-fat diet for 4 weeks suggested that Aloe cellulose might be used as a novel dietary fiber showing an effective anti-obesity and anti-constipation effect.

A Study on the Application of Pre-Indentation Technique for Fastener Hole Model (FASTENER HOLE 모델의 대한 예비압입 적용 연구)

  • Hwang,Jeong-Seon;Jo,Hwan-Gi
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.31 no.9
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    • pp.26-31
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    • 2003
  • Aging aircraft accumulates widespread fatigue damage commonly referred to as multiple site damage(MSO). For ductile material such as 2024-T3 aluminum, MSO may lower the service life below that which is predicted by conventional fracture mechanics. The present paper is concerned with the fatigue life extension by pre-indentation technique for thin 2024-T3 aluminum plate to decelerate the crack propagation rate in the panels with MSO. The panel with fastener holes can be simply modelled by Hole/Slot type Middle-Tension specimen. Results of fatigue testing show significantly improving failure cycles from 10 to 40 times. This retardation effect is decreased by increasing the loading level in the constant amplitude loading. In the sense of retardation mechanism, the crack propagation rate is gradually attenuated by entering the indentation mark and maintains at the lowest value for a long period after the edge of crack passes the center of indentation area.

Retardation of Kimchi Fermentation and Growth Inhibition of Related Microorganisms by Tea Catechins (차엽카테킨의 김치발효 지연 및 관련 미생물의 증식억제)

  • Wee, Ji-Hyang;Park, Keun-Hyung
    • Korean Journal of Food Science and Technology
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    • v.29 no.6
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    • pp.1275-1280
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    • 1997
  • The possible use of tea catechins as natural preservatives for kimchi was investigated in this study. Tea catechins separated from tea leaves had antimicrobial activity against microorganisms related to kimchi fermentation, such as Leuconostoc mesenteroides, Lactobacillus plantarum, Lactobacillus brevis, Pediococcus cerevisiae, Streptococcus faecalis. The degree of antimicrobial activity of catechins were different among microorganisms; that is 2 mg/mL to Leuconostoc mesenteroides, Lactobacillus plantarum, and Pediococcus cerevisiae, 4 mg/mL to Streptococcus faecalis, and 5 mg/mL to Lactobacillus brevis; however, Saccharomyces cerevisiae can not be inhibited. The effect of tea catechins on retardation of kimchi fermentation was tested by measuring changes in pH and acidity. The changes of pH and acidity of baechu-kimchi and mul-kimchi were remarkably inhibited by adding the tea catechins at the level of 2 mg/g fresh baechu. These results suggest that the tea catechins can be successfully used for the extension of shelf-life of kimchi.

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The Effect of Weaning Practices on Linear Growth Retardation in Low-Income Households in Korea (영유아 식이가 성장에 미치는 영향)

  • Park, Hae-Ryun;Gershoff, S.N.;Moon, Hyun-Kyung
    • Journal of Nutrition and Health
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    • v.24 no.4
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    • pp.366-377
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    • 1991
  • A retrospective cohort study of low- income households was carried out on 679 mother-infant pairs to see the effect of weaning practices on growth between March, 1987 and January, 1988 in one rural area, one small city, and one big city, by measuring weight and height of children and intervewing mothers. The sample children showed a linear growth retardation from around 7 or 8 month based on WAZ and HAZ using the Korea Growth Standard. After adjusting both for birth-weight/length and morbidity effect, the ANCOVA test showed that :1) infants who were given supplements were not greater than those of not given. 2) infants who were eating supplements more frequently did not show a larger WAZ or HAZ than those of not eating or sometimes eating them. 3) The caloric intake rates of those of higher food frequencies were not greater than those of lower food frequencies. The context of nutrition education about weaning practices has to be changed stressing not only the early introduction of supplements but also the adequate amount of food intake to secure the rapid growth at this critical age.

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Retardation Effect on the Breach of the Earth Filled Embankment Using the Stiffener During Overtopping (흙댐 제체의 보강재 설치에 따른 월류붕괴 지연효과)

  • Joo, Yo Han;Yeo, Chang-Geon;Lee, Seung Oh
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.4
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    • pp.1377-1387
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    • 2013
  • Most embankment of the reservoirs (99.1 %) have been constructed in the earth filled type in Korea because the construction of this type is less expensive and simpler than others such as concrete one. However, it has to be reinforced the slope to prevent the breach due to overtopping or piping under unexpected flood conditions. This study has been analyzed the retardation effect using three types (L, T, $L^*$ shape) of stiffener in order to reinforce embankment when they are collapsed by overtopping flow. Experimental results showed that L-type stiffener is the most effective in delaying the breaching of embankment and reducing the soil erosion when compared with others. The reinforced embankment breaching showed that time delay was occurred about 1.73 to 2.29 times and the peak flowrate was reduced compared to non-stiffener embankments due to energy dissipation by collision and less soil erosion. The embankment breaching mostly leads to major damages because of the lack of repair time. Thus, since these stiffeners can resist the rapid breach, it would be possible to earn the time to emergency repair and lifesaving, as well as reduction of damages of embankment in downward region with decreasing peak flowrate. Results from this study would be used for the basis when establishing the emergency action plan for the reservoirs on the verge of hazard.

Herbicidal Activity of New Rice Herbicide Pyrimisulfan+Mefenacet SC against Sulfonlurea-Resistant Sea Club Rush (Scirpus planiculmis) (설포닐우레아계 제초제 저항성 새섬매자기에 대한 신규 제초제 Pyrimisulfan+Mefenacet SC의 약제방제 효과)

  • Park, Min-Sik;Park, Yong-Seog;Kim, Sung-Min;Lee, Jeong-Deug
    • Korean Journal of Weed Science
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    • v.31 no.2
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    • pp.192-198
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    • 2011
  • This study was conducted to investigate the herbicidal activity against Scirpus planiculmis (SCPPL) which has been reported as resistant biotype on sulfonylurea (SU) herbicides at the west coast reclaimed area first and proliferated continuously at Hwasung and Pyeongtaek in Gyeonggi province, and some Chungnam province. In order to investigate resistance breakability against SCPPL, new rice herbicides containing tefuryltrione [p-hydrophenyl pyruvate dioxygenase (HPPD) inhibitor], pyrimisulfan and triafamone[actolactate synthethase (ALS) inhibitor] were tested. In both lab and field experiments, tefuryltrione GR, 4-HPPD inhibitor showed growth retardation with a bleaching on the young leaves of SCPPL at early time after treatment. However, it restored and regerminated with insufficient control effect. On the other hand, pyrimisulfan+mefenacet SC, triafamone+tefuryltrione GR, and ALS inhibitor showed excellent control effect on SU-resistant SCPPL with growth retardation and necrosis. In particular, pyrimisulfan+mefenacet SC showed excellent controlling effect on SU-resistant SCPPL in regional field experiments.

Effect of Hwalhyulsungjang-san and KC101 Composed of Oriental Medicinal Stuffs on Physical Development in Growing Rats (활혈성장산과 KC101이 흰쥐의 성장발육에 미치는 영향)

  • 박승만;한찬규
    • The Journal of Korean Medicine
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    • v.24 no.1
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    • pp.1-8
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    • 2003
  • Purpose : Nowadays, there are many studies of growth retardation treatment by oriental medical therapy. This study was performed to evaluate the effect of Hwalhyulsungjang-san (Huoxuechengzhang-san) and KC101 on physical development in growth, Methods : 60 young (3 weeks old) male rats, whose mean weight was $46.8{\pm}0,7g$, were divided into 5 groups : groups A, B, C, and D were fed an experimental diet containing respectively Hwalhyulsungjang-san 2.5%, Hwalhyulsungjang-san 7.5%, KC101 5.0%, and KC101 10.0%, and the other group were fed an AIN-diet containing neither Hwalhyulsungjang-san nor KC101 as a control. Study of each group used 2 rats and was repeated in 6 times. Body weight, daily weight gain, dietary intake, body length, femur length, backbone length and serum concentration of IGF-I and hemoglobin were measured. Result : 1. Body weight and daily weight gain of group D (KC101 10%) were highest; dietary intake of group D was also increased by 13% over the control group. 2. Average body length of group D was increased to 1.69cm, which was 3.2% over the control group. Backbone length of group D was also increased 4% compared to control group. 3. Serum concentration of IGF-I of group D increased 17% compared to control group. 4. Serum concentration of hemoglobin of group B (Hwalhyulsungjang-san 7.5%) increased 8% compared to control group. Conclusion : This study showed that Hwalhyulsungjang-san and KC101 composed of oriental medicinal stuffs have effect on physical development in growing rats. There were not any statistical meaning compared to control group, but this study suggests that intake of these compounds from a young age may lead to increase physical development in growth.

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