• Asian-Australasian Journal of Animal Sciences
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• 제14권3호
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• pp.338-345
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• 2001

An experiment was conducted to determine the optimal inclusion ratio of spray dried plasma protein (SDPP) and dried porcine solubles (DPS) for maximizing growth and improving immunity in weaned pigs. One hundred-fifty male (barrow) pigs were allotted in a completely randomized block design. Treatments were as follows: 1) control (6% SDPP), 2) S6D6 (6% SDPP+6% DPS), 3) S6D3 (6% SDPP+3% DPS), 4) S3D6 (3% SDPP+6% DPS) and 5) S3D3 (3% SDPP+3% DPS). Each treatment has 6 replicates with 5 pigs per replicate. Average daily gain (ADG) and average daily feed intake (ADFI) were highest, but not significantly different when pigs were fed a diet contained 6% SDPP and DPS from d 0 to 7 after weaning. Pigs fed the S6D3 diet showed better weight gain and feed intake than other treatments, especially compared with pigs fed S3D6 diet (p<0.05) from d 8 to 21 after weaning. For the overall experimental period, pigs fed the S6D3 diet showed the best improvement in ADG and ADFI. The digestibilities of dry matter (DM) and crude protein (CP) were higher in pigs fed the S6D6 diet than other diets from d 0 to 7 after weaning. However, pigs fed S6D3 diet showed higher DM, CP and essential amino acids (except methionine and arginine) digestibilities than pigs fed other diets from d 8 to 21 after weaning, although there was no significant difference. From d 8 to 21 after weaning, threonine, valine, isoleucine and leucine digestibilites were higher in S6D6 group, and phenyalanine, histidine, lysine and arginine digestibility were higher in S6D3 group than other groups. The ratio of CD4 and CD8 positive lymphocytes during the overall experimental period was independent of the ratio of SDPP and DPS. However, CD4+:CD8+ ratio was numerically lowered in pigs fed diet the S6D3 diet. Therefore, the present study suggests that an optimal inclusion ratio for maximizing growth performance and maintaining low immune status is 6% of SDPP and 3% of DPS in weaned pigs.

• 대한화학회지
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• 제28권6호
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• pp.399-402
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• 1984

l-tartaric acid를 이용하여 두자리 아민리간드인 6,6'-dimethyl-2,2'-dia minobiphenyl (dmdabp)를 분할하여 S광학이성질체인 S-dmdabp를 얻었다. S-dmdabp로 부터 평면사각형 착물[Pt(S-dmdabp)Cl$_2]$를 합성하였으며, 이 착물에서 S-dmdabp 리간드가 ${\delta}$-confomation으로 배위 되어 있음을 확인하였다.

• 한국자기학회지
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• 제20권6호
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• pp.207-211
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• 2010

우리는 증기전달법(vapor transport method)으로 성장된 $Cr_5S_6$ 단결정의 자기저항 효과를 연구하였다. 상온에서의 X-선 회절 (X-ray diffraction) 연구는 삼방구조(trigonal structure)를 가지는 단결정의 상 형성을 보여주었다. 5 K~400 K 온도영역에서 온도의 함수로 자기장(0.1 T, 5 T)을 걸어주면서 자화를 측정하였다. 자화의 온도의존성 결과로부터 $Cr_5S_6$의 두 가지 상태변화를 확인 할 수 있었다. 첫 번째는 150 K 근처에서 반강자성에서 준강자성으로의 전이가 일어나고, 두 번째는 준강자성에서 상자성으로의 전이가 300 K 근처에서 일어난다. 0 T와 5 T의 자기장에서 측정한 온도에 따른 저항의 변화는 150 K 근처에서 반강자성-준강자성 전이를 보여주면서 금속성을 보여주었다. 자기장의 변화에 따른 자화의 변화를 고정된 온도(100 K, 150 K, 200 K, 그리고 300 K)에서 측정하였다. 200 K과 300 K에서는 M-H 이력 현상을 잘 보여주는 반면에, 100 K과 150 K에서는 이력 현상을 보여주지 않았다. 150 K, 즉 반강자성 전이온도에서 $Cr_5S_6$는 5 T의 자기장 하에서 약 -2%의 음의 자기저항(magnetoresistance)이 관찰되었다.

• 한국안광학회지
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• 제6권1호
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• pp.43-47
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• 2001

구면렌즈와 비구면렌즈를 착용한 피검자의 굴절이상을 중등도근시, 중등도 근시성 복난시, 중등도 혼합난시이상의 착용자를 대상으로 비교하였다. 양안 굴절이상의 구면렌즈 착용자는 S-3.00 ~ S-6.00Dptr 가 16%, S-6.00D Dptr 이상이 19%, S-3.00C-0.50(90.180) ~ S-6.00C-2.00DptrAxis(90.180) 이 57%, S-3.00C+0.50 ~ S-6.00C+2.00DptrAxis(90.180)이 8%로 분포되어 나타났으며, 비구면렌즈 착용자는 S-3.00 S-6.00Dptr이 31%,S-6.00Dptr 이상이 36%, S-3.00C-0.50(90.180) ~ S-6.00C-2.00DptrAxis(90.180)이 21%, S-3.00C+0.50(90.180) ~ S-6.00C+2.00DptrAxis(90.180)이 12%로 분포되었다.

• The Korean Journal of Ceramics
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• 제6권1호
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• pp.43-46
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• 2000

$H_4Nb_6/O_{17}$/CdS nanocomposites which intercalated CdS particles, less than 0.8nm thickness, in the interlayer of $H_4Nb_6/O_{17}$ were prepared by the successive ion exchange reactions of $H_4Nb_6/O_{17}$ with $Cd^{2+}$ and $C_3H_7NH_3_+$, followed by the reaction with $H_2S$ gas. $H_4Nb_6/O_{17}$/CdS photocatalytically reduced $NO_3$￣ to $NO_2$￣ and $NH_3$in the presence of sacrificial hole acceptor such as methanol under visible light irradiation (wavelength>400nm), although unsupported CdS showed no noticeable photocatalytic activity for $NO_3$￣ reduction. The catalytic activity of $H_4Nb_6/O_{17}$/CdS greatly enhanced with co-doping of Pt particles in the interlayer.

• Archives of Pharmacal Research
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• 제25권5호
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• pp.685-690
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• 2002

The mitogen-stimulated serine/threonine kinase $p70^{S6k}$ plays an important role in the progression of cells from $G_0/G$_1$$ to S phase of the cell cycle by translational up-regulation of a family of mRNA transcripts family of mRNA transcripts which contain polypyrimidine tract at their 5 transcriptional start site. Here, we report that $p70^{S6k}$ was constitutively phosphorylated and activated to various degrees in serum-deprived AGS, A2058, HT-1376, MG63, MCF7, MDA-MB-435S, MDA-MB-231 and MB-157. Rapamycin treatment induced a significant dephosphorylation and inactivation of $p70^{S6k}$ in all cancer cell lines, while wortmannin, a specific inhibitor of PI3-K, caused a mild dephosphorylation of $p70^{S6k}$ in AGS, MDA-MB-435S and MB-157. In addition, SQ20006, methylxanthine phosphodiesterase inhibitor, reduced the phosphorylation of $p70^{S6k}$ in all cancer cells tested. Consistent with inhibitory effect of rapamycin on $p70^{S6k}$ activity, rapamycin inhibited [$^3H$]-thymidine incorporation and increased the number of cells at $G_{0}G_{1}$ phase. Furthermore, these inhibitory effects were accompanied by the decrease in growth of cancer cells. Taken together, the results indicate that the antiproliferative activity of rapamycin might be attributed to cell cycle arrest at $G_{0}G_{1}$ phase in human cancer cells through the inhibition of constitutively activated $p70^{S6k}$ of cancer cells and suggest $p70^{S6k}$ as a potential target for therapeutic strategies aimed at preventing or inhibiting tumor growth.

• 약학회지
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• 제38권5호
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• pp.544-554
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• 1994

Pyrrolidine-2,3-dione derivative A was synthesized from oxalylation of chiral enamine Ba. The stereostructure of its major diastereomer $(A_{maj})$ was determined as octahydro-2,3-dioxo-6aS-hyd roxy-1-(1S-methoxycarbonyl-2-phenylethyl)-cyclopenta[b]pyrrole-3aR-carboxylic acid ethyl ester Aa by means of NMR spectrum. This result implied that the asymmetric carbon-carbon bond forming reaction occurred preferentially at the ${\beta}-face$ of Ba.

• 대한화학회지
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• 제45권3호
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• pp.242-246
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• 2001

사성분계 thiophosphates, $A_2NiP_2S_6>(A=Rb$, Cs)를 halide fluxes 법으로 합성하였으며 단결정 X-ray 회절방법으로 결정 구조를 해석하였다. 이 화합물들을 $C_{2h}^5-P2_1/n$ 의 공간군을 가지며, $Rb_2NiP_2S_6$의 경우 a=5.960(2), b=12.323(4), $c=7.491(3)\AA$, $\beta=97.05(3)^{\circ}$, $V=546.0(3)\AA^3$이고$Cs_2NiP_2S_6$의 경우 a=5.957(4),b=12.696(7), $c=7.679(4)\AA$, $\beta=93.60(5)^{\circ}$, $V=579.7(5)\AA^3$인 격자상수를 갖는다. 이 두화합물은 동일한 결정 구조를 갖는다. 이들의 구조는 결정학적인 a축을 따라 성장한 1차원적인 무한사슬 $_{\infty}^1[NiP_2S_6^{2-}]$로 구성되어 있으며 이 사슬들은 알칼리 금속과의 정전기적 인력을 통하여 안정화 되어있다. Ni원자는 6개의 S원자에 의해 팔면체 배위를 하고 있고, Ni$S_6$팔면체는 $[P_2S_6^{4-}]$ 음이온 3개의 $\mu-S$ 원자들에 의해 연결되어 무한 1차원적인 사슬을 형성한다. $Cs_2NiP_2S_6$에 대한 자화율 측정결과 Neel temperature($T_N$)에 상응하는 8K 이하에서 superexchange를 통한 반자기성 magnetic coupling을 발견하였다. $T_N$이상의 온도에서는 Curie-Weiss법칙을 따른다. 자기 모멘트, C(Curie), 그리고 $\theta$(Weiss Constant)는 각각 2.77 B.M., 0.9593K, 그리고 -19.02K 이다. 측정 결과로부터 얻은 유효 자기 모멘트는 spin-only $Ni^{2+}d^8$(2.83 B.M.)계의 결과와 일치한다.

• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1182-1190
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• 2014

$Cd_{1-x}Zn_xS$-sensitized $K_4Nb_6O_{17}$ composite photocatalysts (designated $Cd_{1-x}Zn_xS/K_4Nb_6O_{17}$) were prepared via a simple deposition-precipitation method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDS), $N_2$ sorption, ultraviolet-visible light diffuse reflectance spectroscopy (UV-Vis DRS), photoluminescence measurements (PL), and X-ray photoelectron spectroscopy (XPS). The $Cd_{0.8}Zn_{0.2}S$ particles were scattered on the surface of $K_4Nb_6O_{17}$, and had a relatively uniform size distribution around 50 nm. The absorption edge of $K_4Nb_6O_{17}$ was shifted to the visible light region and the recombination of photo-generated electrons and holes suppressed after $Cd_{0.8}Zn_{0.2}S$ loading. The $Cd_{0.8}Zn_{0.2}S$(25 wt %)/$K_4Nb_6O_{17}$ composite possessed the highest photocatalytic activity for hydrogen production under visible light irradiation, evolving 8.278 mmol/g in 3 h. Recyclability tests were performed, and the composite photocatalysts were found to be fairly stable. The mechanism of charge separation between the photogenerated electrons and holes at the $Cd_{0.8}Zn_{0.2}S/K_4Nb_6O_{17}$ composite was discussed.

• 대한화학회지
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• 제45권1호
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• pp.7-13
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• 2001

양이온 계면활성제인 TTAB(tetradecyltrimethylammonium bromide)의 수용액에서 benzenesulfonate 음이온과 유도체($C_6H_5SO_3^-, p-$CH_3C_6H_4SO_3^- 및 $p-C_2H_5C_6H_4SO_3^-$)들의 가용화 현상을 UV/Vis 분광광도법을 이용하여 연구하였다. 온도의 변화에 따른 가용화상수($K_s$)의 변화를 측정하고 분석하였으며, 또한 가용화에 영향을 미치는 n-펜탄올과 NaBr의 효과에 대하여 조사하였다. 이러한 첨가제는 $K_s$와 CMC 값을 동시에 큰 폭으로 감소시키는 경향을 나타내었으며, 측정한 In$K_s$ 값은 InCMC 값에 대하여 일차함수의 관계를 나타내었다. 그리고 열역학적 고찰을 위하여 온도에 따른 $K_s$ 값의 변화로부터 여러 가지 열역학 함수값(${\Delta}G^0_s$, ${\Delta}H^0_s$ 및 ${\Delta}S^0_s$)을 계산하고 분석하였다.