• 제목/요약/키워드: $k_La$

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호소수내 암모니아성 질소 및 인 동시 제거를 위한 란탄-제올라이트 복합체 개발 (Development of La(III)-zeolite Composite for the Simultaneous Removal of Ammonium Nitrogen and Phosphate in Confined Water Bodies)

  • 백주헌;김금용;류홍덕;이상일
    • 대한환경공학회지
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    • 제32권8호
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    • pp.761-766
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    • 2010
  • 본 연구에서는 인 및 암모니아 흡착에 효과적인 La(III) 및 제올라이트를 적절히 결합하여 호소수 및 연못 등의 질소 및 인을 동시에 효과적으로 제거할 수 있는 La(III)-zeolite 복합체 개발을 목적으로 하였다. 연구 결과 La(III)-zeolite 복합체 제조 시 최적 결합 비는 0.0048 La(III) g:1 zeolite g 인 것으로 나타났다. 복합체 제조 시 건조 온도는 인 흡착에 결정적인 영향을 주는 것으로 나타났는데 상온 건조가 가장 적합한 것으로 관찰되었다. La(III)-zeolite 복합체 최적 주입량은 4.052 g/L로 나타났다. La(III)-zeolite 복합체 주입 시 최적 흡착 시간은 90 분으로 나타났다. 수용액상에서 알칼리도의 존재는 암모니아 및 인흡착에 긍정적인 영향을 주는 것으로 관찰되었다. 상온에서 건조시킨 La(III)-zeolite 복합체는 용액 내에서 La(III)의 탈리 현상이 관찰되지 않았으며, 이는 La(III)-zeolite 복합체가 인을 흡착하여 바닥에 가라앉은 후 바닥으로부터 용출되는 인을 효과적으로 차단 할 수 있음을 의미한다.

고지혈증 유발 백서에서 열결 ${\cdot}$ 여구에 대한 침자 및 강도별 레이저조사가 체중, 식이효율, 지질대사 및 동맥경화지수에 미치는 영향 (Effects of acupuncture and low level laser acupuncture therapy (LLLAT) at Yolgyol (LU7), Yogu (LR5) in hyperlipemia rats induced by high rat diet)

  • 나창수;윤대환;조명래;강자돈
    • Korean Journal of Acupuncture
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    • 제24권1호
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    • pp.113-129
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    • 2007
  • Objectives : This research was performed to investigate the effect of acupuncture using invasive low level laser therapy (LLLT) at Yolgyol (LU7) + Yogu (LR5) on weight gain, food intake, food efficiency, lipid metabolism, atherogenic index, HTR (HDL-cholesterol to total cholesterol ratio) and morphological change of hepatic tissue in hyperlipdemia rats. Methods : Experimental groups were divided into high fat diet group (Control group), high fat diet and acupuncture therapy group at LU7 + LR5 (AT group), high fat diet and acupuncture group using 10 mW LLLT at LU7 +LR5 (LA10 group), high fat diet and acupuncture group using 20 mW LLLT at LU7+LR5(LA20 group), high fat diet and acupuncture group using 60 mW LLLT at LU7 + LR5 (LA60 group), once per 3 days during 9 weeks. Results : Body weight was decreased significantly in AT and LA20 groups compared with Control group. Food intake was increased significantly in LA60 group compared with Control group. Food efficiency was decreased significantly in LA10, LA20 and LA60 groups compared with control group. In the lipid metabolism, total cholesterol was decreased significantly in AT, LA10, LA20 and LA60 groups, triglyceride was decreased significantly in LA10, LA20 and LA60 groups, TG/HDL-cholesterol ratio was decreased significantly in LA 60 group compared with control group. In the morphological change, hepatic tissue were not showed balloning degeneration and irregular arrangement of hepatic cell in LA10 and LA20 groups with control group. Conclusions : Acupuncture using LLLT at LU7+LR5 can manage hyperlipemia by controlling body weight, food intake, food efficiency ratio and lipid metabolism.

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$(LaS)_xCrS_2(x{\approx}1.20)$의 결정구조와 자기적 특성 (Crystal Structure and Magnetic Properties of $(LaS)_xCrS_2(x{\approx}1.20)$)

  • 조남웅;유광수;정형진
    • 한국재료학회지
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    • 제4권6호
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    • pp.704-709
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    • 1994
  • Crystal Structure and Magnetic Properties of $(LaS)_xCrS_2(x \approx 1.20$)가 1273K에서 $La_S_3$ , Cr, S의 혼합물의 반응으로부터 합성되었다. $(LaS)_xCrS_2( x\approx 1.20$)의 XRD회절 pattern은 monoclinic의 LaS-부격자, triclinic의 $CrS_{2}$-부격자와 그들의 초격자로서 해석되었다. 부격자의 온도의존성을 저온에서 X-선 회절분석으로 조사하였다. 77K~실온의 온도역에서 $(LaS)_xCrS_2(x \approx 1.20$)의 자기자화율을 Faraday balance법으로 측정하였다. $(LaS)_xCrS_2(x \approx 1.20$)은 실온 $\sigma$ -H plot에서 paramagnetic한 거동을 나타내었다. 관측된 유효자기 moment($\mu_{eff}$)는 $Cr^{3+}$을 spin-only에 의한 것과 $La^{3+}$을 spin-only와 orbital에 의한 것으로 계산할 경우 잘 일치되었다.

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원자발광광도법에 의한 란탄족 원소의 정밀분석에 관한 연구 (제 1 보) 희토류-EDTA 용리액에 의한 희토류 원소의 분리 회수 (Study on the Precision Analysis of Lanthanides by Atomic Emission Spectroscopy (I). Separation of Rare Earth Elements Using Ln-EDTA Eluent)

  • 차기원;오진희;하영구;김하석
    • 대한화학회지
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    • 제36권5호
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    • pp.692-696
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    • 1992
  • $NH_4^+형 양이온 교환수지와 희토류-EDTA 용리액을 사용하여 희토류 원소 혼합물에서 원하는 한 원소를 분리 회수하는 연구를 하였다. NH_4^+형 양이온 교환수지에 희토류 혼합물을 흡착시키고, La-EDTA 용액으로 용리하면 수지에 흡착된 희토류 원소중 La^{3+} 이온 외의 희토류 원소는 용리된다. 수지에 남아있는 La^{3+}은 EDTA 용리액으로 용리하여 분리한다. Ce^{4+}만 선택적으로 분리하고자 할때는 La-EDTA 대신 Ce-EDTA로 용리하고 수지에 남은 Ce^{4+}을 EDTA로 용리하면 된다. 이때 분리 구조는 다음과 같다. 흡착과정 : 3RNH_4 + Ln^{3+} = R_3Ln + 3NH^{4+}, La-EDTA 용리 : R_3Ln + La-Y- = R_3La + Ln-Y^-, EDTA 용리 : R_3La + HY^3- = La-Y + RH + 2R-.$

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Bioconversion of Linoleic Acid to Conjugated Linoleic Acid by Bifidobacterium breve

  • Song Yoon-Seok;Kang Seong-Woo;Oh Deok-kun;Rho Yong-Taik;Hong Suk-In;Kim Seung-Wook
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제10권4호
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    • pp.357-361
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    • 2005
  • The bioconversion of linoleic acid (LA) to conjugated linoleic acid (CLA) was investigated to examine LA-adaptation of Bifidobacterium breve KCTC 3461 to additions of 1 to 5 mg/mL of LA overtime. To induce LA-adaptation, B. breve KCTC 3461 was treated with LA, according to three schemes. For LA-adapted B. breve the maximum concentration of CLA, $300\~350{\mu}g/mL$, was obtained in cys-MRS medium containing 1 mg/mL of LA. The CLA production significantly increased with increasing LA concentration, from 1 to 4 mg/mL, but the conversion of LA to CLA gradually decreased. The CLA production capability of B. breve, and its tolerance, improved significantly with LA-adaptation. The addition of LA (1 mg/mL) into the culture broth after 24 h of cultivation in a 100-mL media bottle was most effective at promoting CLA production. In a 2.5-L stirred-tank bioreactor, the observed conversion and productivity of $56.6\%\;and\;35.4{\mu}gmL^{-1}h^{-1}$, respectively, by LA-adapted B. breve were approximately 6.6 and 9.8 times higher than those of LA-unadapted B. breve.

삼릉(三稜)이 자궁경부암세포(子宮頸部癌細胞)(HeLa cell)의 Apoptosis에 미치는 영향(影響) (Rhizoma Scirpi induced Apoptosis in Human Cervical Carcinoma HeLa Cells)

  • 홍기철;김주연;공복철;최창민;유심근
    • 대한한방부인과학회지
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    • 제18권4호
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    • pp.10-23
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    • 2005
  • Purpose : This study is to examine the ability of Rhizoma Scirpi (RS) to induce HeLa cell viability. Methods : We culture HeLa cell which is human metrocarcinoma cell in D-MEM included 10% fetal bovine serum(Hyclone Laboratories) below $37^{\circ}C$, 5% CO2. Then we observed apoptosis of log phage cell which is changed cultivation liquid 24 Hours periodically. Results : 1. RS induces mitochondria membrane potential collapse. 2. P38 MAPK is involved in RS-induced death in HeLa cells. 3. P38 MAPK is involved in RS-induced apoptosis in HeLa cells. 4. P38 MAPK reguates RS-induced caspase-3, -8 and -9 activation in HeLa cells. 5. The inhibition of caspase regulates RS-induced cell death in HeLa cells. 6. RS induces mitochondria membrane potential collapse in HeLa cells. 7. P38 MPK is involved in the regulation of Bcl-2 and Bfu in HeLa cells.8. RS regulates the expression of Bcl-2 and Bax in HeLa cells. 9. SR induces p38 MAPK activation in HeLa cells. Conclusion : RS induces apoptosis in HeLa cells via p38 MAPK activation.

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치환된 $LaMnO_3$의 환원반응성에 대한 연구 (Study on the reducibility of substituted $LaMnO_3$)

  • 이상범;전현표
    • 자연과학논문집
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    • 제14권2호
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    • pp.41-54
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    • 2004
  • $LaMnO_3$(a=$5.51\AA$, c=$13.33\AA$) 페로브스카이트형 복합산화물에서 A site인 La자리에 Sr을 치환시킨 $La_{0.9}Sr_{0.1}MnO_3$(a=$5.33\AA$, c=$13.27\AA$)와 B site인 Mn을 Cu로 치환시킨 $LaMn_{0.9}Cu_{0.1}O_3$(a=$5.52\AA$, c=$13.31\AA$) 복합산화물을 Citrate sol-gel법을 이용하여 합성하였으며 분말 X-ray회절 분석기(XRD)을 이용하여 Rhombohedral의 페로브스카이트 구조임을 확인하였다. 수소 환원분위기에서의 TRR결과에 의하면 이들 산화물의 산소 화학양론은 $LaMnO_{3.16}$, $La_{0.9}Sr_{0.1}MnO_{3.10}$, $LaMn_{0.9}Cu_{0.1}O_{3.14}$의 조성을 갖는다. $LaMnO_3$는 2단계 환원반응을 일으키지만 각 자리를 치환시킨 $LaMnO_3$ 복합산화물은 3단계 환원반응을 일으켰다.

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Assessment of Dipping Treatment with Various Lactic Acid or Sodium Benzoate Concentrations to Extend the Shelf-life of Spent Hen Breast Meats

  • Gu, Ja-Gyeong;Park, Jung-Min;Yoon, Su-Jin;Ahn, Byoung-Ki;Kang, Chang-Won;Song, Jae-Chul;Kim, Jin-Man
    • 한국축산식품학회지
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    • 제31권3호
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    • pp.428-435
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    • 2011
  • This study was conducted to investigate the effect of immersion treatment using lactic acid (LA) and sodium benzoate (SB) on the physicochemical quality and freshness of spent hen breast meats. A total of 135 spent hen breast meats were subjected to 9 different treatments using various concentrations of LA and/or SB in sterile DW. The 9 treatment groups were as follows: Control, sterile DW without LA or SB; T1, 1% LA; T2, 2% LA; T3, 4% LA; T4, 1% LA and 0.1% SB; T5, 2% LA and 0.1% SB; T6 2% LA and 0.2% SB; T7, 2% LA and 0.4% SB; T8, 4% LA and 0.2% SB, respectively. All groups were kept at 4oC for 15 d. The microbial counts in the control group gradually increased during storage, but those for the treated groups were significantly lower than the control or were not detected. The pH values of the control were significantly higher than those of the treated groups (p<0.05). In the color measurements, the lightness ($L^*$) and yellowness ($b^*$) values increased during storage and the redness ($a^*$) values decreased (p<0.05). The K-value and volatile basic nitrogen of the treated groups were significantly lower than those of the control group (p<0.05). Overall, the combined results of this study indicate that LA and SB could be used as favorable preservatives for spent hen breast meats to extend their shelf-life during refrigerated storage.

$Al^{3+}$, $Pr^{3+}$가 첨가된 Perovskite $La_{2/3}TiO_{3}와 Pyrochlore $La_{2}Ti_{2}O_{7}$의 발광 특성 (Photoluminescence Behavior of $Al^{3+}$, $Pr^{3+}$ Doped Perovskite-type $La_{2/3}TiO_{3}and Pyrochlore-type $La_{2}Ti_{2}O_{7}$)

  • 박상미;박정규;김창해;박희동;장호겸
    • 한국세라믹학회지
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    • 제38권9호
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    • pp.806-810
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    • 2001
  • $La_{2/3}TiO_3$, $La_2Ti_2O_7$는 유전성을 갖는 특징으로 인해 여러 분야에 이용되고 있다. 본 연구는 perovskite 구조의 $La_{2/3}TiO_3$와 pyrochlore 구조의 $La_2Ti_2O_7$를 모체로 하여 $Al^{3+},\;Pr^{3+}$가 첨가된 형광체의 발광 특성을 알아보고자 하였다. 두 구조 모두 $Pr^{3+}의\;^1D_2{\rightarrow}^3H_4$ 전이에 의한 적색 발광을 나타내었다. 본 연구에서는 perovskite 구조의 $La_{2/3}TiO_3$:Pr 형광체의 에너지 전이 과정과 그 임계거리에 대한 조를 통해 에너지 전달체로서의 $Al^{3+}$의 역할을 제시하였다. 또한, perovskite 구조의 $La_{2/3}TiO_3$와 pyrochlore 구조의 $La_2Ti_2O_7$ 사이의 발광특성 차이를 알아보기 위해서 trap-involved process와 charge transfer band를 조사하였다.

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Fabrication of $(La, Sr)MO_3$ (M=Mn or Co)/YSZ Nanocomposite Thin Film Electrodes for the Exhaust Gas Purification by a Chemically-Modified Sol-Gel Process

  • Hwang, H.J.;Moon, J.W.;Awano, M.;Maeda, K.
    • 한국분말재료학회지
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    • 제8권3호
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    • pp.201-206
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    • 2001
  • $>LaMnO_3$$(La, Sr)MO_3$, and $(La, Sr)MO_3/YSZ$ gel films were deposited by spin-coating technique on scandium-doped zirconia (YSZ) substrate using the precursor solution prepared from $La(O-i-C_3H_7)_3$, $Co(CH_3COO)_2$or $Mn(O-i-C_3H_7)_2$,2-methoxyethanol, and polyethylene glycol. By heat-treating the gel films, the electrochemical cells, $(La, Sr)MnO_3{\mid}ScSZ{\mid}Pt$ were fabricated. The effect of polyethylene glycol on the microstructure evolution of $$LaCoO_3and $LaMnO_3$thin films was investigated, and NOx decomposition characteristics of the electrochemical cells were investigated at $500^{\circ}C$ to $600^{\circ}C$. By applying a direct current to the $(La, Sr)MnO_3{\mid}ScSZ{\mid}Pt$ electrochemical cell, good NOx conversion rate could be obtained relatively at low current value even if excess oxygen is included in the reaction gas mixture.

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