• 제목/요약/키워드: LlF

검색결과 83건 처리시간 0.03초

Development and Decay of Columnar Vortex in two faces interface ; gas/liquid and solid/liquid

  • Lee, Seung-Hwan;Kim, Kyung-Hoon;Kim, Seok-Woo
    • 한국분무공학회지
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    • 제6권2호
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    • pp.29-36
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    • 2001
  • Vortices terminating at free surface have been investigated extensively. however. are focused on surface parallel vortices and little has been known about surface normal vortex or columnar vortex. Visualized experimental results utilizing LlF technique are discussed for the purpose of characterization of columnar vortex interacting with a clean and a contaminated free surfaces and a solid body interface in the present investigation. The results reveal that surface tension changes due to surface contamination although bulk viscosity remains constant and eventually the behavior of a columnar vortex interacting with a contaminated free surface and a solid body interface are totally different from the clean free surface case.

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무릇에서 분리한 nortriterpenoid glycoside의 암세포에 대한 세포독성 및 함량 분석 (Cytotoxicity and Quantitative Analysis of Nortriterpenoid glycoside from Scilla scilloides)

  • 이상명;전효곤;이충환;이호재;강진정;맹학영;고영희
    • 생약학회지
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    • 제32권3호통권126호
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    • pp.189-192
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    • 2001
  • Scillascilloside E-3 (1) and E-1 (2) were isolated from the bulbs of Scilla scilloides. The cytotoxic activities of these compounds were tested against murine (B16/F-10, 3LL) and human cancer cell lines (MCF7, PC-3, HT29, LOX-IMVI, A549 and HT1080). These compounds exhibited a significant cytotoxic activities against all tested cancer cells. Futhermore, the contents of 1 and 2 in S. scilloides are 43.2 and 27.9 mg/kg, respectively.

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나노초 UV 레이저를 이용한 분말사출 부품의 미세기공 (Micromachining of powder injection molded parts using ns UV laser)

  • 안대환;박성진;권영삼;김동식
    • 한국레이저가공학회지
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    • 제13권1호
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    • pp.1-5
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    • 2010
  • ln this work, the feasibility of using a UV laser for micromachining of powder injection molded parts is examined experimentally. The results, although preliminary, indicate that microfabrication of various parts by laser micromachining of the injection molded parts and then sintering is promising. Particularly, micromachining of a mixture composed of stainless steel particles and polyrner binders was studied using a KrF excimer laser.

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Perspectives on the Quality Assurance of Ginseng Products in North America

  • Fitzloff, J.F.;Yat, P.;Lu, Z.Z.;Awng, D.V.C.;Arnason, J.T.;Breemen, R.B.van;Ha, T.ll;Blumenthal, M.;Fong, H.H.S.
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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    • pp.138-145
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    • 1998
  • A validated and reproducible HPLC method was developed for the profiling and quantitative analysis of ginsenosides in commercial products available in North America. Analysis of 280 Panax ginseng and Panax quinquefolius products showed profiles indicative of the presence of ginsenosides in the majority of these products. However, the quantitative contents of the products vary greatly, not only in products of different formulations, but also of products within each of the fromulations examined.

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3차 PLL SYSTEM에서의 flicker noise 분석 (Flicker noise analysis in the third-order of the PLL system)

  • 김형도;김경복;오용선;조형래
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 1999년도 추계종합학술대회
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    • pp.230-235
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    • 1999
  • 본 논문에서는 PLL 시스템의 보다 실제적인 모델인 3차 시스템을 통하여 저주파 대역에서 문제가 되는 flicker noise가 어떠한 양상을 나타내는가를 알아보려 한다. 3차에서 해석의 복잡성으로 그 수학적 분석의 난해함을 나타내지만 최적화 된 2차 필터를 통한 pseudo -damping factor의 도입으로 전체적인 flicker variance의 해석이 용이하도록 시도하였다. 3차에서의 flicker variance의 수식적인 유도를 보이고 이를 2차 시스템에서 발생되는 flicker noise 에 대한 variance와 비교 하려한다

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Investigation of the Insulin-like Growth Factor System in Breast Muscle during Embryonic and Postnatal Development in Langshan and Arbor Acres Chickens Subjected to Different Feeding Regimens

  • Lu, F.Z.;Chen, J.;Wang, X.X.;Liu, Honglin
    • Asian-Australasian Journal of Animal Sciences
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    • 제22권4호
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    • pp.471-482
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    • 2009
  • Nutrient availability may control muscle growth directly and indirectly through its influence on regulatory factors. We analyzed the effects of nutrient availability on the breast muscle insulin-like growth factor system. Real time RT-PCR was used to quantify the level of transcription in breast muscle from Langshan (LS) layer and Arbor Acres (AA) broiler chickens subjected to different feeding regimens during embryonic and postnatal development. The AA chickens were fed AA diet (AA, control group) while the LS chickens were either fed LS diet (LL) or AA diet (LA). According to our results, insulin-like growth factor (IGF)-II (embryonic day 16 (E16) - postnatal day 42 (P42)), IGF-I receptor (IGF-IR, E18-P42), and IGF binding protein (IGFBP)-2 (E18-P42), -5 (E16-P14), -7 (E12-P0), and -3 (E12-P0) were positively correlated with IGF-I, while IGFBP-3 (P0-P28) was negatively correlated with IGF-I. In comparison, IGF-IR (E18-P42), IGFBP-2 (E18-P42), IGFBP-5 (E14-P0), and IGFBP-3 (E16-P0) were positively correlated with IGF-II, while IGF-IR (E10-E16) and IGFBP-3 (P0-P28) were negatively correlated with IGF-II. Moreover, IGFBP-2 (E16-P42), -7 (E10-E16), and -3 (E10-E16) were positively correlated with IGF-IR, while IGFBP-3 (P0-P28) was negatively correlated with IGF-IR. Finally, IGFBP-7 (E12-P0) was positively correlated with IGFBP-3, while IGFBP-2 (P0-P28) and -7 (P0-P42) were negatively correlated with IGFBP-3. Overall, the AA chickens exhibited higher levels of IGF-I, IGF-IR, and IGFBP-2 mRNA expression than the LL chickens, while the opposite was true for IGFBP-7. No strain differences in IGF-I, IGF-IR, and IGFBP-7 mRNA expression were detected between LA and AA chickens; however, a strain difference was observed for IGFBP-2. LA chickens exhibited higher levels of IGFBP-2 than LL chickens, while the opposite was true for IGFBP-7. Our data show the first evidence that certain genes may be correlated during specific developmental periods and that strain differences in the expression of those genes in LS and AA chickens are due to differential responses to the same diet.

TPM-BiP 청색 형광 재료의 전계발광특성 (Characterization of Blue Organic Light Emitting Diodes using TPM-BiP)

  • 장지근;신상배;안종명;장호정;이학민;공명선;김민영;김준우
    • 반도체디스플레이기술학회지
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    • 제6권2호
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    • pp.11-14
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    • 2007
  • For the fabrication of blue color organic light emitting diodes(OLED) with a high performance, 2-TNATA [4,4',4"-tris (2-naphthylphenyl-phenylamino)-triphenylamine] as hole injection material and NPB [N,N'-bis (1-naphthyl) -N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine] as hole transport material were deposited on the ITO (indium tin oxide)/glass substrate by the vacuum thermal evaporation. After then, blue color emission layer was deposited using TPM-BiP[(4'-Benzoylferphenyl-4-yl)phenyl-methanone-Diethyl(biphenyl-4-ymethyl)phosphonate] and GDI602 as a light emitting organic material. Finally, the two kinds of OLEDs with the structure of $ITO/2-TNATA/NPB/TPM-BiP/Alq_3/LiF/Al and ITO/2-TNATA/NPB/GDI602/Alq_3/LiF/Al$ were prepared by in-situ deposition. The maximum current density and luminance were found to be about $588\;mA/cm^2\;and\;5239\;cd/m^2$ at 12V for the OLED sample with the structure of $ITO/2-TNATA/NPB/TPM-BiP/Alq_3/LiF/Al$. Color coordinate of blue OLED was x=0.18, y=0.18 (at llV) and the maximum current efficiency was 2.82 cd/A (at 6V) with the peak emission wavelength of 440 nm.

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Statistical Genetic Studies on Cattle Breeding for Dairy Productivity in Bangladesh: II. Estimation of Reciprocal and Heterosis Effects and Optimum Crossbreeding System between the Local Breeds and Exotic Breeds for Milk Performance

  • Hossain, K.B.;Takayanagi, S.;Miyake, T.;Bhuiyan, A.K.F.H.;Sasaki, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권6호
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    • pp.777-782
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    • 2002
  • Reciprocal effects among local breeds and additive and heterosis effects were estimated for total milk production per lactation (TLP), lactation length (LL) and daily milk yield (DMY). Procedures for an optimum crossbreeding system were examined by comparing various crossbred combinations. Three data sets were chosen from the total records collected from 1962 to 1997. Data set I with a total of 5,938 records composed of 9 breed groups for reciprocal crosses, data set II with a total of 6,064 records composed of 5 breed groups for additive and heterosis effects and data set III with a total of 10,319 records composed of 42 breed groups for optimum crossbreeding system were analyzed. The least squares ANOVA was used. The reciprocal crosses between Red Sindhi and the Bangladeshi Local showed significant difference. When the Red Sindhi was used as cow, the cross was superior to the opposite in terms of the three performance traits. The results showed that additive breed effects on both TLP and DMY were positive and highly significant between Bos indicus and Bos taurus, whereas the individual heterosis effects were not significant. In general, any local breeds were improved two to three times by crossing with the Friesian once or twice. However, the effect was reduced when the grading up with the Friesian was repeated more than twice. On the other hand, when the local breed was crossed with the other breeds such as Holstein and Jersey, the improvement of TLP was less. Crossing the F1 cows with the Friesian bull gave further improvement. Almost the same trends were found also for LL and DMY. The local breeds and their crosses are raised mainly for draft animals, then it is recommended that the crossbreds between the local cows and Friesian are used for dairy purposes and more than 75% Friesian blood is used for beef.

Bis(p-substituted phenyl) 2-decyloxyterephthalate의 액정 특성에 대한 치환기 효과 (The Effect of Substituents on LC Behavior of Bis(p-substituted phenyl) 2-Decyloxyterephthalate)

  • 박주훈;이종규;최옥병;소봉근;이수민;이준우;진정일
    • 대한화학회지
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    • 제44권2호
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    • pp.127-137
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    • 2000
  • 비스(파라-치환페닐)테레프탈산 에스테르의 중앙 테레프탈산 벤젠고리 측면에 데실옥시기가 결합하고 있는 열한개의 새로운 화합물을 합성하였고, 이들의 열적 및 액정 성질을 DSC와 가열판이 부착된 편광현미경을 사용하여 조사하였다. 메소겐의 말단 치환기 X= -H(II-H), -F(II-F), -Cl(Il-Cl), -Br(Il-Br), -I(II-I), -$NO_2(lI-NO_2$), $-CF_3(II-CF_3$), -$OC_2H_5(II-OC_2H_5$), -$OC_4H_9(II-OC_4H_9$), -CN(II-CN) 및 -$C_6H_5(Il-C_6H_5$)로 바꾸었다. $II-OC_2H_5,\;II-OC_4H_9$, 및 $II-C_6H_5$는 단방성 네마틱 액정이었으며, II-H, lI-F, II-Cl, Il-Br, II-I, $II-NO_2$, $II-CF_3$, 및 Il-CN은 액정이 아니었다.

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새로운 항균제(抗菌劑)로서 1-(phenoxymethyl)benzotriazole 유도체(誘導體)의 합성(合成)과 정량적(定量的) 구조활성관계(構造活性關係)(QSAR) 분석(分析) (Synthesis and quantitative structure-activity relationships(QSAR) analysis of 1-(phenoxymethyl) benzotriazole derivatives as new fungicide)

  • 성낙도;임치환;최우영;고동성;권기성
    • Applied Biological Chemistry
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    • 제33권3호
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    • pp.231-238
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    • 1990
  • 14종의 새로 합성된 1-(phenxymethyl)benzotriazole(I)(Y=0)과 1-(thiophenoxymethyl)benzotriazole (II)(Y=S) 및 1-(azidomethy) benzotriazole(III) 유도체의 구조와 in vitro에서 Pyricularia oryzae, Fusarium axysporum f.sp.sesami, Valsa ceratosperma 및 Botrytis cinerea에 대한 균사 생장을 50% 저해하는 활성($pI_{50}$)사이의 구조-항균활성 상관관계들을 QSAR방법으로 연구하였다. (I)의 항균활성은 (II)와 (III)보다 우세하였으며 phenoxy group(I)의 치환기 효과는 수소 결합성 (HB)과 포물선 관계의 electronic effect($\sigma$), steric effect($B_1$)그리고 hydrophobic effect($\pi$)로 설명된다. P. oryzae와 F. axysporum f.sp.sesami의 항균 활성에 대한 치환기의 적정값은 $B_1$=1.40A, (H)와 $\sigma=0.07{\sim}0.15$, (H)이고 V. ceratosperma와 B. cinerea에 대하여는 각 각 $\sigma=0.23{\sim}0.28$, (C1)과 $\pi=0.70$, (C1)이었으며 가장 호과적인 화합물인 ( I a)와 ( I d)의 구조-활성관계가 검토되었다.

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