• 제목/요약/키워드: $b_H$

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Bacillus polyfermenticus SCD의 Three Layer Coating에 의한 pH, 열, 높은 glucose 농도에 대한 안정성효과 (Increased Stability of Bacillus polyfermenticus SCD in Low pH, High Temperature and High Glucose Concentration via Three Layer Coating)

  • 이진옥;전경동;강재선;이재화
    • KSBB Journal
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    • 제19권3호
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    • pp.221-225
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    • 2004
  • Bacillus sp. 유래의 Bacillus polyfermenticus SCD를 Bisroo $t^{ⓡ}$라고 부르고, 이것은 생균제로서 산업적으로 매우 유용하다. 본 연구에서는 B. polyfermenticus SCD를 산업적으로 활용성을 증대시키기 위해 three layer coating법을 사용하여 인공위액의 pH 변화에 대한 안정성과 열안정성, glucose 농도에 따른 안정성을 연구하였다. 그 결과 코팅한 B. polyfermenticus SCD가 인공위액에 대한 내성에서는 배양 4시간을 기준으로 pH 2는 30%, pH 4는 20%, pH 6은 14% 상승효과가 있었음을 알 수 있었고, 온도변화에 대한 안정성에서는 코팅한 B. polyfermenticus SCD가 8$0^{\circ}C$에서 2시간 기준으로 안정성이 약 40% 증진됨을 확인할 수 있었다. 고농도 (30%)의 glucose에서 코팅한 B. polyfermenticus SCD는 안정하였으며, 코팅하지 않은 것보다 약 50% 안정성이 증대됨을 확인할 수 있었다. 그리고 pH 4.0에서는 코팅한 B. polyfermenticus SCD는 코팅을 하지 않은 B polyfermenticus SCD보다 전체적으로 생존율이 40% 이상, pH 6.0에서는 생존율이 42% 이상 증진됨을 알 수 있었다.

비만세포에서의 창이자의 탈과립 및 pro-inflammatory cytokines 분비량에 미치는 영향 (Xanthium strumarium suppresses degranulation and pro-inflammatory cytokines secretion on the mast cells)

  • 류지효;윤화정;홍상훈;고우신
    • 한방안이비인후피부과학회지
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    • 제21권3호
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    • pp.82-93
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    • 2008
  • Objective: Previously, the methanol extracts of the semen of Xanthium strumsrium could involved anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated Raw 264,7 cells, We evaluated the anti-allergic effects of X. strumarium on rat basophilic leukemia (RBL-2H3) cells, Methodes : To investigate the effect of X. strumarium on the phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187-induced RBL-2H3 cells. The effects of X. strumarium on the degranulation and the pro-inflammatory cytokines secretion and expression from RBL-2H3 cells were evaluated with $\beta$-hexosaminidase assay, ELISA, and RT-PCR analysis, In addition, we examined the effects of X. strumarium on nuclear factor (NF)-${\kappa}B$ activation and $I{\kappa}B-\alpha$ degradation using Western blot analysis. Results : X. strumarium inhibited degranulation and secretions and expressions of pro-inflammatory cytokines, such as tumor necrosis factor-alpha ($TNF-\alpha$), interleukin (IL)-4 and cyclooxygenase (COX)-2, on stimulated RBL-2H3 cells, however, X. strumarium not affect cell viability. In stimulated RBL-2H3 cells, the protein expression level of nuclear factor-kappa B (NF-${\kappa}B$) was decreased in the nucleus by X. strumarium. In addition, X. strumarium suppressed the degradation of inhibitory protein $I{\kappa}B-{\alpha}$ protein in RBL-2H3 cells. Conclusion : These results suggest that X. strumarium inhibits the degranulation and secretion of pro-inflammatory cytokines through blockade of NF-${\kappa}B$ activation and I $I{\kappa}B-{\alpha}$ degradation.

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A COMPARISON OF COTTONSEED AND FORMALDEHYDE-TREATED SUNFLOWER MEALS ON THE PRODUCTION OF BOS INDICUS AND BOS TAURUS CATTLE ON A SUB-TROPICAL PASTURE HAY

  • Hennessy, D.W.;Williamson, P.J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제1권2호
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    • pp.107-114
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    • 1988
  • Six steers of each breed type, Hereford ($H{\times}H$), Brahman ($B{\times}B$) and Brahman $\times$ Hereford ($B{\times}H$) were ranked on liveweight and allocated to three treatments, basal hay diet (Basal), Basal plus 1 kg/head/day of cottonseed meal (Basal + CSM) and Basal plus 1 kg/head/day of formaldehyde-treated sunflower meal, $Norpro^{(R)}$ (Basal + NPO). The hay was made from a pasture based predominantly on carpet grass (Axonopus affinus) growing in subtropical New South Wales, and had an estimated organic matter digestibility of 52% and a nitrogen (N) content of 7.8 g/kg dry matter (DM). The steers were accustomed to the Basal diet over 15 days and supplements offered over 42 days. Intake of the basal hay diet by steers was not increased by supplementation. When intakes were adjusted for differences between breed types in liveweight the $B{\times}H$ steers ate 25% (P<0.01) more hay than $H{\times}H$ steers (6.3 V 5.0 kg/head/d) and $B{\times}B$ steers ate 8% less hay than $H{\times}H$ steers. Supplementation significantly (P<0.01) increased liveweight gain during the experiment, being ($g/head/d\;{\pm}\;s.e.d.$) 290, 770 and $795{\pm}118$ respectively for Basal, Basal + NPO and Basal + CSM. There was no difference between supplements in the liveweight gain of steers nor between steers of different genotypes. However, there was a significant interaction (P<0.01) between breeds and treatments such that $B{\times}B$ steers gained most on the basal diet but least of the breed types when supplemented. The estimated non-degradeable fraction of N in the protein meals was 58.5 and 44.5%, respectively for NPO and CSM. Both meals increased (P<0.01) plasma urea N and rumen ammonia N concentrations.

B2O3-P2O5-SiO2 계 박막유리의 화학증착 및 물성에 관한 연구 (A Study on the Chemical Vapor Deposition of BPSG and its Thin Film Properties)

  • 김은산;양두영;김동원;김우식;최민성
    • 한국세라믹학회지
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    • 제28권7호
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    • pp.517-524
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    • 1991
  • The CVD process of BPSG (BoroPhosphoSilicate Glass) and its thin film properties were studied. B2H6, PH3, SiH4 and O2 gases were reacted in a AP (Atmospheric Pressure) CVD system in the temperature range of 300℃ and 460℃. The interaction of B2H6 and PH3 was studied from the deposition rate and dopant incorporation change point of view. The dependency of BPSG step coverage on the temperature was changed with different O2/(B2H6+PH3+SiH4) ratio. Finally, the boundary which distinguishes the stable BPSG's from the ones that react with Di (Deionized) water or cleaning chemicals such as H2SO4, HCl, H2O2, NH4OH etc could be defined.

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Expanding Generalized Hadamard Matrices over $G^m$ by Substituting Several Generalized Hadamard Matrices over G

  • No, Jong-Seon;Song, Hong-Yeop
    • Journal of Communications and Networks
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    • 제3권4호
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    • pp.361-364
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    • 2001
  • Over an additive abelian group G of order g and for a given positive integer $\lambda$, a generalized Hadamard matrix GH(g, $\lambda$) is defined as a gλ$\times$gλ matrix[h(i, j)], where 1 $\leq i \leqg\lambda and 1 \leqj \leqg\lambda$, such that every element of G appears exactly $\lambd$atimes in the list h($i_1, 1) -h(i_2, 1), h(i_1, 2)-h(i_2, 2), …, h(i_1, g\lambda) -h(i_2, g\lambda), for any i_1\neqi_2$. In this paper, we propose a new method of expanding a GH(g^m, \lambda_1) = B = [B_{ij}] over G^m$ by replacing each of its m-tuple B_{ij} with B_{ij} + GH(g, $\lambda_2) where m = g\lambda_2. We may use g^m/\lambda_1 (not necessarily all distinct) GH(g, \lambda_2$)s for the substitution and the resulting matrix is defined over the group of order g.

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비 막힘형 수중 펌프 임펠러 형상이 펌프 성능에 미치는 영향 (Effects of Impeller Shape of Submersible Nonclogging Pump on its Performance)

  • 윤정의
    • 대한기계학회논문집B
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    • 제36권12호
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    • pp.1201-1207
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    • 2012
  • 본 연구에서는 15kW 모터로 구동되는 $5m^3$/min의 유량을 고효율로 공급할 수 있는 2엽 비막힘형 수중 펌프의 임펠러를 설계하는 것을 목표로 임펠러 출구 위치 변화($h_I$), 출구 폭($b_2$) 및 허브 프로파일이 펌프 성능에 미치는 영향을 상용 해석용 프로그램 ANSYS CFX를 사용한 전산해석을 통해 수행하였다. 해석 결과, 임펠러 출구 위치 변화($h_I$) 및 출구 폭($b_2$)이 증가하면 양정 및 축동력의 경우는 $h_I$, $b_2$와 함께 지속적으로 증가하지만 효율의 경우는 $h_I$=38 mm, $b_2$=55 mm 까지만 증가하며, 그 이상의 값에서는 일정한 값을 가짐을 보여준다. 그리고 허브 프로파일의 변화는 상대적으로 임펠러 성능에 큰 영향을 미치지는 않는다.

자기센서용 Fe78B13Si9/PZT/Fe78B13Si9 적층구조 소자의 ME 특성 (Magnetoelectric Characteristics on Layered Fe78B13Si9/PZT/Fe78B13Si9 Composites for Magnetic Field Sensor)

  • 류지구;전성즙
    • 센서학회지
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    • 제24권3호
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    • pp.181-187
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    • 2015
  • The magnetoelectric characteristics on layered $Fe_{78}B_{13}Si_9/PZT$ and $Fe_{78}B_{13}Si_9/PZT/Fe_{78}B_{13}Si_9$($t_m=0.017$, 0.034mm) composites by epoxy bonding for magnetic field sensor were investigated in the low-frequency range and resonance frequency range. The optimal bias magnetic field $H_{dc}$ of these samples was about 23~63 Oe range. The Me coefficient of $Fe_{78}B_{13}Si_9/PZT/Fe_{78}B_{13}Si_9(t_m=0.034mm)$ composites reaches a maximum of $186mV/cm{\cdot}Oe$ at $H_{dc}=63Oe$, f=50 Hz and a maximum of $1280mV/cm{\cdot}Oe$ at $H_{dc}=63Oe$, resonance frequency $f_r=95.5KHz$. The output voltage shows linearity proportional to ac fields $H_{ac}$ and is about U=0~130.6 mV at $H_{ac}=0{\sim}7Oe$, f=50 Hz, U=0~12.4 V at $H_{ac}=0{\sim}10Oe$, $f_r=95.5KHz$(resonance frequency). The optimal frequency(f=50 Hz) of this sample is around the utility ac frequency(f=60 Hz). Therefore, this sample will allow for ac magnetic field sensor at utility frequency and low bias magnetic fields $H_{dc}$.

새로운 적분기를 이용한 모터 코어 특성시험 장치 (A new integrator based measuring system for testing motor core material)

  • 박영태;이진호;장석명;이성호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 A
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    • pp.61-63
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    • 1998
  • A B-H curve measuring system for testing softmagnetic materials was constructed. This system can measure the B-H curve in the low frequency(0.1 - 1 Hz) range. The drift of the integrator can be moderately removed by software technique. The advantages of the developed system are easier to measure B-H curve compared with conventional measuring system and low cost.

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Tautomeric and Ab Initio Studies of 5-Thioxo-3H,4H-1,3,4-thiadiazolidin-2-one

  • 조남숙;박창권;김현숙;최은숙;강성권
    • Bulletin of the Korean Chemical Society
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    • 제19권1호
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    • pp.103-106
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    • 1998
  • The oxidation product bis(2-oxo-3H-1,3,4-thiadiazolidinyl)-5,5-disulfide (5b) was obtained from an attempted synthesis of 5-thioxo-3H,4H-1,3,4-thiadiazolidin-2-one (1). Spectroscopic results indicate that the most stable tautomeric form of 1 is the lactam-thiol form (1b). The computed total energies and relative energies at the MP4 level also showed that the most stable tautomer is 1b.