• 제목/요약/키워드: Tg.AC

검색결과 43건 처리시간 0.017초

자동차 차체용 알루미늄 합금 판재의 기계적특성과 부식피로수명 (A mechanical proprties and fatigue life of aluminum alloy sheets for autobodies)

  • 박인덕;윤옥남;남기우
    • 한국해양공학회지
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    • 제11권2호
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    • pp.57-69
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    • 1997
  • The objetive of this study is to compare the mechanical proprties of 6000 series Al-Mg-Si aluminum alloy (AC120) with 5000 series Al-Mg aluminum alloy (TG25), and to investigate the influence of corrosion solution for fatigue life. Comparing of TG25 and AC120 alloy sheets, TG25 alloy sheets showing higher plastic ratio and total elongation have better formability than AC120 alloy sheets. The hardness of nugget area was a little higher than that of base metal area. Also, grain coarsening was observed in HAZ(Heat Affected Zone). In a corrosion fatigue experiment, the fatigue life decreased as concentration increased, when a dipping time was constant. The life decreased as dippling time increased, when a concentration was constant.

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Transglutaminase와 도토리 및 녹두 가루 첨가가 저지방/저염 돈육 모델소시지의 품질에 미치는 영향 (Effect of Transglutaminase, Acorn, and Mungbean Powder on Quality Characteristics of Low-fat/salt Pork Model Sausages)

  • 이홍철;진구복
    • 한국축산식품학회지
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    • 제29권3호
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    • pp.374-381
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    • 2009
  • 본 연구는 저지방/저염 돈육 모델 소시지 제조에 있어서 transglutaminase(TG, 1.0%)와 sodium caseinate(SC, 0.5%)의 첨가와 0.3%의 도토리 또는 녹두 가루의 첨가가 가열 처리한 최종 제품의 이화학적 및 조직학적 특성에 미치는 효과를 평가하기 위한 목적으로 실시하였다. 제조된 저지방/저염 돈육 모델 소시지는 TG와 SC 첨가에 의해 pH가 높아지고, 수분 함량 및 명도가 낮아졌다. 한편, 저지방/저염 돈육 모델 소시지의 보수성과 조직감 측정결과에서는 TG와 SC 첨가가 유리수분량에 영향을 주지 않은 반면에, 제품 수율은 감소되었으며, 소시지의 모든 조직감은 증진되었다. 도토리 또는 녹두 가루 첨가에 의한 소시지의 보수성 및 조직감의 변화는 도토리나 녹두 가루 첨가 모두 저지방/저염 돈육 모델 소시지의 수율을 상승시켰으며, 보수성 또한 증진시켰다. 특히 녹두 가루 첨가는 도토리 가루 첨가보다 더 높은 보수성 효과를 나타냈다. 반면에, 도토리나 녹두 가루의 첨가는 소시지의 씹힘성의 증진을 제외한 다른 조직 감에는 영향을 주지 않았다. 이러한 결과를 종합해 볼 때, TG와 SC의 첨가는 저지방/저염 돈육 제품의 조직감 향상에 매우 효과적인 반면에 도토리나 녹두 가루의 첨가는 TG와 SC의 첨가에 의한 보수성의 저하를 보완하는데 긍정적인 효과를 보였다.

열중량 분석에 의한 DGEBA/MDA/PGE-AcAm/CTBN계의 열적 안정성 평가 (Estimation of Thermal Stability for DGEBA/MDA/PGE-AcAm/CTBN System by TG Analysis)

  • 이재영;최형기;심미자;김상욱
    • 한국재료학회지
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    • 제7권3호
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    • pp.229-233
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    • 1997
  • Diglycidyl ether of bisphenol A(DGEBA)/4,4'-methylene dianiline(MDA)/phenyl glycidyl ether(PGE)-acetamide(AcAm)/carboxyl-terminated acrylonitrile butadiene copolymer(CTBN) 계의 열적 안정성을 평가하기 위해 열중량 분석법(TG)을 사용하였다. 활성화 에너지를 구하기 위해 Freeman & Carrol, kissinger, Flynn & Wall 식을 사용하였다. Freeman & Wall 식을 이용하여 구한 활성화 에너지는 112.9 kJ/mol, Kissinger 식에 의한 값은 151.5kJ/mol 이었으며, Flynn & Wall식에 의해 구한 값은 168.3 kJ/mol 이었다.

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DGEBA/MDA계의 인장 및 충격 특성에 미치는 PGE-AcAm의 영향 (Effects of PGE-AcAm on the Tensile and Impact Properties of DGEBA/MDA System)

  • 이재영;심미자;김상욱
    • 한국재료학회지
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    • 제7권6호
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    • pp.460-463
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    • 1997
  • 에폭시 수지 계의 경화반응 속도를 증가시키고 기계적 물성을 향상시키기 위해 합성 pheny1 glycidy1 ether(PGE)-acetamide(AcAm)를 diglycidy1 ether of bispenol A(DGEBA)/4,4'-methylene dianiline(MDA)계에 도입하였다. PGE와 AcAm을 2:1의 몰비로 혼합한 후 18$0^{\circ}C$에서 1시간 반응시켜서 PGE-AcAm을 합성하였다. 5phr의 PGE-AcAm이 첨가되었을 때 인장강도가 15% 개선되었으며, 그 이후로는 PGE-AcAm을 합성하였다. 5phr의 PGE-AcAm이 첨가되었을 때 인장강도가 15% 개선되었으며, 그 이후로는 PGE-AcAm의 함량에 관계없이 거의 비슷한 값을 나타내었다. 반면에유리전이 온도(Tg)와 충격강도는 PGE-AcAm의 함량이 증가함에 따라 감소하였다. 파단면은 PGE-AcAm이 첨가됨으로써 더 복잡한 형상을 나타내었다.

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Two Dinucleotide Repeat Polymorphisms (AC/TG and GT/CA) in the 5' Upstream Region of the Mouse Tryptophan Hydroxylase Gene

  • Yim, Sung-Vin;Chi, Sung-Gil;Chung, Sung-Hyun;Lee, Hee-Jae;Kim, Mi-Ja;Park, Seung-Joon;Jung, Jee-Chang;Chung, Joo-Ho
    • The Korean Journal of Physiology and Pharmacology
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    • 제3권5호
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    • pp.501-505
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    • 1999
  • Tryptophan hydroxylase (TPH), the rate-limiting enzyme in serotonin biosynthesis, is primarily expressed in serotonergic neurons of the raphe nuclei. Simple tandem repeat polymorphisms, typically one to four nucleotides long, are tandemly repeated several times and often characterized by many alleles. To identify the presence of polymorphic repeats, we sequenced the 5'-upstream region of the mouse TPH gene. For the detection of any allelic variants, polymerase chain reaction, nonisotopic single-strand conformation polymophism, and DNA sequencing analyses of the tandem repeat sequences were performed using genomic DNA extracted from 60 ICR mice. Two dinucleotide repeats, $5'-(AC/TG)_{22}-3'$ and $5'-(GT/CA)_{17}3',$ were identified at approximately - 5.7 kb and - 3.4 kb upstream from the transcriptional initiation site of the mouse TPH gene, respectively. Minor allelic variants, $5'-(AC/TG)_{21}-3'$ and $5'-(GT/CA)_{18}-3',$ were observed in heterozygous pairs from 3 of 60 and 1 of 60 ICR mice, respectively. The identification of these microsatellites in the mouse TPH promoter raises the possibility that identical and/or other polymorphic sequences might exist in the upstream region of the human TPH gene.

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As-Te-Si-Ge 유리질 반도체의 전기전도에 관한 연구 (A Study on Electrical Conduction of As-Te-Si-Ge Amorphous Semiconductor)

  • 박창엽;왕진석;정홍배
    • 대한전자공학회논문지
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    • 제12권2호
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    • pp.18-23
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    • 1975
  • As-Te.Si-Ge 유리질 반도체의 직류 펀도도는 실온에서 3x10-7Ω-1cm-1∼1.5x10-8Ω-1cm-1이었고 각 시료의 온도 인화에 따른 전도특성은 상전이 온도(Tg) 이하에서 o=ooexp(-△E/kT)로 표시할 수 있었다. 또한 실온에서 각 시료의 교류 전도도의 주파수 의존도는 거의 같았으며 직류 전도도에 비해 상당치 높게 나타나서 o(w)=oo+Awn으로 표시할 수 있었다. 200KHz 경우에 교류 펀도도는 295。K∼473。K에서 온도에 무관하고 200Hz 경우에는 433。K에서 부터 심하게 증가하였다. 각 시fy는 기억스위칭 현상은 없었고 문지받스위칭 현상만 관찰할 수 있었다. The dc conductivity, ac conductivity and switching effect of As·Te-Si·Ge have beon investigated. The dc conductivity ranged from 3x10-7Ω-1cm-1∼1.5x10-8Ω-1cm-1 at room temperature and was found to be expressed by o=ooexp(-△E/kT) below the phase transition temperature Tg. The ac conductivity was much higher than dc conductivity and this result is consistent to experimental formula o(w)=oo+Awn. In the temperature range of 298。K∼147。K, the ac conductivity was independent of temperature at 200KHs. At lower frequencies the ac conductivity increased strong1y with temperature. Also, it has been found that all samples showed a threshold switching, but not a memory switching.

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리튬황전지의 임피던스 특성 (Impedance Properties of Lithium Sulfur Batteries)

  • 김파;김종욱;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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    • pp.444-447
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    • 2002
  • The Jig cells are fabricated in the drying room, and consisted of elemental sulfur used as a cathode active material, lithium metal used as a anode material and 1M $LiCF_{3}SO_{3}$ dissolved in TG (Tetraglyme)/DIOX (1,3-Dioxolane) used as a electrolyte. The four kinds of electrolytes with different content of TG and DIOX are prepared. The electrochemical properties of the foregoing electrolytes-based lithium sulfur batteries are analyzed by AC impedance experiments. The conductivity of four different electrolytes is investigated. The conductivity of electrolyte [1M $LiCF_3SO_3$ dissolved in TG/DIOX (50:50, vol.)] is higher than that of other three kinds of electrolytes with different volume ratio (70:30, 30:70) and single solvent (TG).

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Tumorigenicity of benzo(a)pyrene and benzo(a)pyrene diol epoxides in v-Ha-ras transgenic TG-AC mice

  • 이병무
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 1998년도 국제심포지움 및 추계학술대회
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    • pp.36-36
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    • 1998
  • Tumorigenicity of benzo(a)pyrene (BP) and benzo(a)pyrene diol epoxides ((+)BPDE-1, (-)BPDE-1) was investigated in transgenic TG-AC mice carrying v-Ha-ras oncogene fused to the promoter of the mouse embryonic a-like, z-globin gene. Animals were topically treated twice per week for 25weeks with BPDE (10$\mu$g/mouse) and BP (10, 20, 40$\mu$g/mouse). In addition, animals were treated with BPDE or BP (initiated) followed by TPA (2$\times$2.5$\mu$g/week, for 4 weeks) for promotion study. In the continuous treatment of BPDE or BP, animals treated with 40$\mu$g BP showed $100\%$ tumor response after 20 weeks, $40\%$ of mice for 20$\mu$g BP, and $20\%$ for (+)BPDE-1, but (-)BPDE-1 and 10$\mu$g BP did not show any tumor response. After 25 weeks, most tumors turned out to be carcinomas in animals treated with 40$\mu$g BP. In BPDE or BP/TPA Initiation-promotion study, papilloma response occurred earlier (6 weeks after TPA treatment) than in continuously treated animals with BPDE or BP. RT-PCR assay for transgene expression showed that BP or BPOE was not transgene dependent in its tumorigenicity, but TPA was. Several Cytokine genes(TGF-a, TNF-a) and c-myc gene expressions were monitored in skin tissues during BP carcinogenesis. In early stage of BP treatment, the gene expressions were elevated(c-myc,TGF-a) or unchanged(TNF-a) compared to control, but the levels were gradually decreased during both middle and late stages of cacinogenesis, Gene expression levels of skin papillomas in acetone initiated-TPA promoted animals were close to those of middle stage or between middle and late stages. i-NOS was also highly expressed in carcinoma and papilloma, These data suggest that transgene expressions of TG-AC mice were not dependent on BP carcinogenesis and that TG-AC mice were more sensitive to TPA regardless of types of initiators. In addition, genes(TGF-a, c-myc, TNF-a, i-NOS) were modulated in the skin during BP cacinogenesis or TPA promotion.

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Effects of Allium Vegetables on Energy Stores and Utilization in Exercising Rats

  • Kong, Eun-Young;Cho, Youn-Ok
    • Preventive Nutrition and Food Science
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    • 제9권1호
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    • pp.39-44
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    • 2004
  • This study investigated the effect of allium vegetable intake on the storage and utilization of energy substrates before, during, and after exercise in tissues of rats. Ninety rats were fed either a control diet or a diet with added Allium sativum (AS, garlic), Allium cepa (AC, onion), Allium fistulosum (AF, spring onion), or Allium tuberosum (AT, Chinese chives) for 4 weeks and were then subdivided into 3 groups: before-exercise (BE); during-exercise (DE); after-exercise (AE). The DE group was exercised on treadmill for 1 hour just before being sacrificed at the end of 4th week of the dietary treatment rats in the AE group were allowed to recuperate for 2 hours after being exercised like the DE group. The levels of glycogen (GLY), triglyceride (TG) and protein (PRO) were compared in liver and skeletal muscle. In the AS diet animals, the level of liver GLY was significantly higher than those of control animals in the BE, DE and AE groups. The level of muscle TG also tended to be higher in BE, but lower in AE than in control animals. In AC animals, the level of muscle GLY was significantly lower than those of control animals in BE, DE and AE. The level of muscle TG also tended to be higher than those of control animals in BE and DE but tended to be lower in AE. In AF animals, the level of muscle GLY was significantly lower than those of control animals in BE, DE and AE. The level of muscle TG was also significantly lower than those of control animals in BE, DE and AE groups. In AT animals, the level of muscle GLY was significantly lower than those of control animals in BE, DE and AE. These results suggest that Allium sativum diets enhance the capacity to store fuel before as well as during exercise and increases the potential to utilize the stored fuel during exercise.

The Effect of Allium Vegetable Intake on the Utilization and Recuperation of Plasma Fuel in Acute-Exercising Rats

  • Cho, Youn-Ok;Kong, Eun-Young
    • Nutritional Sciences
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    • 제6권3호
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    • pp.155-159
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    • 2003
  • Ninety rats were fed either a control diet or one of several allium vegetable diets (allium sativum (AS), allium cepa (AC), allium fistulosum (AF) or aliium tuberosum (AT) for 4 weeks and were separated into 3 groups : non-exercise (NE), exercise (EX), and exercise and recuperation (ER), The EX group was exercised on a treadmill for 1 hour just before sacrifice at the end of 4th week of diet intake and the ER group was recuperated for 2 hours after exercise. The levels of glucose (GLU), (PRO), triglyceride (TG), free fatty arid (FFA) and hemoglobin (Hb) were compared in plasma. In the U group, GLU levels of AS and AC tended to be higher than those of the control group. There were no differences in GLU levels between the control group and the allium vegetable groups in EX, whereas GLU levels of AS, AF and AT tended to be lower than that of control group in ER. There were no differences in PRO among the groups NE, EX and ER. TG and EEh levels of AS, AC, AF and AT tended to be lower than those of the control group in NE, EX and ER. Hb levels of AS, AC, AF and AT were lower than that of the control group in U and ER and tended to be lower than that of EX. These results suggest that allium vegetable diets have the potential to enhance the capacity to oxidize fatty acid and to recover triglyceride after recuperation, although there is compensation among stored fuel utilization during exercise