• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.224-225
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• 2006

The Ethylene polymerization behavior of a series of polymethylene bridged dinuclear CGC $[Zr({\eta}^{5}:{\eta}^{1}-C_{9}H_{5}SiMe_{2}NCMe_{3})Me_{2}]_{2}[(CH_{2})_{n}]\;[_{n}=6(1),\;9(2),\;12(3)]$ in the cocatalytic activation with $Ph_{3}C^{+}B^{-}(C_{6}F_{5})_{4}\;(B_{1})\;or\;Ph_{3}C^{+}(C_{6}F_{5})_{3}B^{-}C_{6}F_{4}B^{-}(C_{6}F_{5})_{3}Ph_{3}C^{+}\;(B_{2})\;or\;B(C_{6}F_{5})_{3}\;(B_{3})$ were investigated to study the nuclearity effects as well as the counteranion effects. The ethylene polymerization and ethylene/1-hexene copolymerization were conducted at $30^{\circ}C$ It was found that both in ethylene polymerization and ethylene/1-hexene copolymerization, activities increased in the order of 1 < 2 < 3, which indicates the presence of longer bridge between two active sites contributes more efficiently to facilitate the polymerization activity.

• Korean Chemical Engineering Research
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• 제47권1호
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• pp.84-88
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• 2009

Al이 치환된 $LiMn_2O_4$ 미세 분말을 구연산과 에틸렌 글리콜이 첨가된 분무용액으로부터 분무열분해 공정에 의해 합성하였다. 구형의 형상, 다공성의 구조 및 마이크론 크기를 가지는 전구체 분말들은 $800^{\circ}C$ 이상의 후열처리 온도에서 마이크론 크기 및 균일한 형태를 가지는 $LiMn_{11/6}Al_{1/6}O_4$ 분말들로 전환되었다. 후열처리 온도가 $700^{\circ}C$ 일 때 $LiMn_{11/6}Al_{1/6}O_4$ 분말은 94 mAh/g의 낮은 초기 방전 용량을 가졌다. 후열처리 온도가 $750^{\circ}C$에서 $1,000^{\circ}C$로 증가함에 따라 $LiMn_{11/6}Al_{1/6}O_2$ 분말의 초기 방전 용량은 103 mAh/g에서 117 mAh/g로 변화하였으며, 후열처리 온도 $750^{\circ}C$에서 최대 초기 방전용량을 가졌다. 반면에 후열처리 온도 $900^{\circ}C$에서 얻어진 $LiMn_{11/6}Al_{1/6}O_2$ 분말들이 좋은 사이클 특성을 가졌다. 전류밀도 0.1 C에서 70 사이클 충방전 후에 $LiMn_{11/6}Al_{1/6}O_4$ 분말들의 방전 용량은 107 mAh/g에서 100 mAh/g으로 감소하였고 93%의 사이클 효율을 유지하였다.

• 미생물학회지
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• 제29권6호
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• pp.380-386
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• 1991

Three types of soluble cytochrome c were purified to homogeneity from Methylobacillus sp. strain SK1 which grows only on methanol. Cytochrome c-I was purified 58.5-fold in seven steps. Cytochrome c-II and c-III were purified 57.3- and 122.1-fold in eight steps, respectively. The molecular weights of the cytochrome c-I was determined to be 12,500, while those of the cytochrome c-II and c-III were 16,000. The isoelectric points of the c-I, c-II and c-III were found to be 8.8, 6.6, and 6.6 respectively. The spectrum of reduced cytochrome c-I showed .alpha.-, .betha.-, .gamma.-peaks at 551.4, 522.2, and 416.6nm. The peaks for c-II were found at 551.0, 521.6, and 416.5nm, while those for c-III were shown at 551.2, 521.8, and 416.0 nm. The spectra of oxidized cytochrome c-I, c-II, and c-III showed .gamma.-peak at 411.8, 409.0, and 410.2 nm, respectively. The absorption coefficients of .alpha.- and .gamma.-peak for c-I in the reduced state were determined as 47 and 197 $mM^{-1}$ $cm^{-1}$ , respectively. The coefficients of .alpha.- and .gamma.-peak for c-II were determined to be 43 and 137 $mM^{-1}$ $cm^{-1}$ , while those for c-III were 41 and 172 $mM^{-1}$ $cm^{-1}$ , respectively. The c-I and c-III were found to bind carbon monoxide.

• 한국안광학회지
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• 제5권2호
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• pp.99-105
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• 2000

작업환경에서 시력저하가 나타나는 굴절이상의 종류별 분포는 안경사 100명, 사진기사 100명, 대학생 100명중 단성근시 35% 근시성 단난시 2% 근시성 복난시 30.6% 혼합난시 6.26% 원시성 복난시 3.74% 정시 22.4%의 순으로 나타났다. 양안 굴절이상의 근시도수 분포는 -0.50~-2.00 Dptr가 전체 대상자중 14%, -2.00~-6.00 Dptr 이상이 16% -6.00 Dptr 이상이 5%로 나타났으며, 근시성 단난시의 분포는 C-0.25(90, 180)~C-2.00 Dptr Axis(90, 180) 2%, 근시성 복난시의 분포는 S-0.25 C-0.25 Dptr Axis(90, 180)~S-1.00 C-1.00 Dptr Axis(90, 180)이 22.6%, S-1.00 C-1.00 Dptr Axis(90, 180)~S-2.00 C-2.00 Dptr Axis(90, 180)이 8%로 나타났다. 혼합난시의 분포는 S+0.25 C-0.25 Axis(90, 180)~S+2.00 C-2.00 Axis(90, 180)가 6.26%, 원시성 복난시의 분포는 S+0.25 C+0.25 Axis(90, 180)~S+1.00 Dptr Axis(90, 180)가 3.4%, S+1.00 C+1.00 Axis(90, 180)~S+2.00 C+2.00 Dptr Axis(90, 180)가 0.34%의 순으로 나타났다.

• 한국염색가공학회지
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• 제9권1호
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• pp.44-49
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• 1997

Recent investigation and developments of A. Iqbal on diketo-pyrrolo-pyrrole (DPP) pigments has prompted us to synthesize and close observation of a few properties of these molecules. Described are synthesis, via 1-phenyl-2-ethoxycarbonyl-5-pyrrolinone intermediate, of asymmetric derivatives such as 1,4-Diketo-3-(4-chlorophenyl)-6-phenyl-pyrrolo-(3,4c)-pyrrole (4), 1,4-Diketo-3-(4-bromophenyl)-6-phenybpyrrolo-(3,4c)-pyrrole (5), 1,4-Diketo-3-(3-cyanophenyl)-6-phenyl-pyrrolo-(3,4c)-pyrrole (6), 1,4-Diketo-3-(4-cyanophenyl)-6-phenyl-pyrrolo-(3,4c)-pyrrole (7), 1,4-Diketo-3-(4-pyridyl)-6-phenyt-pyrrolo-(3,4c)-pyrrole (8), 1,4-Diketo-3-(3-pyridyl)-6-phenyl-pyrrolo-(3,4c)-pyrrole (9), 1,4-Diketo-3-(2-pyridyl)-6-phenyl-pyrrolo-(3,4c)-pyrrole (10), 1,4-Diketo-3-($\beta$-naphthyl)-6-phenyl-pyrrolo-(3,4c)-pyrrole (11), and UV-Vis absorption spectrum of the above compounds. Results from calculation of their absorption maxima using PISYSTEM are also described.

• Natural Product Sciences
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• 제19권4호
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• pp.360-365
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• 2013

Baicalin has antioxidant, anti-inflammatory and anti-diabetic properties. IL-6 is a primary proinflammatory cytokine that contributes to impaired insulin signaling in liver. This study was carried out to investigate whether baicalin improves IL-6-mediated insulin resistance in liver. Hepa-1c1c7 cells were pre-treated with 50 and 100 ${\mu}M$ baicalin in complete media for 1 h and then cultured in the presence or absence of IL-6 (20 ng/ml). These results demonstrated that baicalin restored IL-6-suppressed expression of insulin receptor substrate (IRS)-1 protein, downregulated IL-6-increased gene expression of C-reactive protein (CRP) and suppressor of cytokine signaling (SOCS)-3, and inhibited LPS-induced production of IL-6 in Hepa-1c1c7 cells. These findings indicate that baicalin may ameliorate hepatic insulin resistance via improvement of IL-6-mediated impaired insulin signaling in hepatocytes.

• Genomics & Informatics
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• 제2권2호
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• pp.75-80
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• 2004

In a variety of animal species, the perinatal exposure of experimental animals to the 2,3,7,8-tetrachlorodibenzo­p-dioxin (TCDD) leads to the immune dysfunction, which is more severe and persistent than that caused by adult exposure. We report here the changes of gene expression and the identification of the marker-genes representing the dioxin exposure. The expressions of the transcripts were analyzed using the 11 K oligonucleotide­microarray from the bone marrow cells of male C57BL/6J mice after an intraperitoneal injection of $1{\mu}g$ TCDD/kg body weight at various time intervals: gestational 6.5 day(G6.5), 13.5 day(G13.5), 18.5 day(G18.5), and postnatal 3 (P3W)and 6 week (P6W). The type of self-organizing maps(SOM) representing the specific exposure dioxin could be identified as follows; G6.5D(C14), G13.5D(C0, C5, C10, C18), G18.5D(7): P3W(C2, C21), and P6W(C4, C15, C20). The candidate marker-genes were restricted to the transcripts, which could be consistently expressed greater than $\pm$2-fold in three experiments. The resulting candidates were 85 genes, the characteristics of that were involved in cell physiology and cell functions such as cell proliferation and immune function. We identified the biomarker-genes for dioxin exposure: smc -like 2 from SOM C14 for the dioxin exposure at G6.5D, focal adhesion kinase and 6 other genes from C0, and protein tyrosine phosphatase 4a2 and 3 other genes from C5 for G13.5D, platelet factor 4 from C7 for G18.5D, fos from C2 for P3W.

• 한국결정학회지
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• 제12권3호
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• pp.137-140
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• 2001

화합물 PdCl₂(PhC≡N)₂(1) 와 2.6-diisopropylaniline 이 반응하여 trans-[Pd(NH₂-C/sub 6/-H₃-2, 6-i-Pr₂)₂Cl₂] (2)가 합성하였다. 화합물 2의 구조가 분광학적 방법(¹H-NMR, /sup 13/C-NMR, IR) 및 X-ray 회절법으로 규명되었다. 화합물 2의 결정학 자료: 단사정계 공간군 P2₁/n, a=13.532(3)Å, b=5.749(1)Å, c=17.880(4)Å, β=103.84(2)°, Z=2, R(wR₂)=0.0466(0.1226).

• 동의생리병리학회지
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• 제24권6호
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• pp.1004-1011
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• 2010

This study was designed to evaluate the protective effects of Dodamtanggami-bang (DDTG) on tunicamycin induced cell death by ER stress in C6 glial cells. Cell viability was measured by MTT assay and LDH release. Apoptosis was determined by caspase activity and flow cytometry in C6 glial cells. Expression of ER stress mediators including, GRP78 and CHOP proteins were measured by Western blot analysis. Tunicamycin induced the apoptosis of C6 glial cells, which was characterized as nucleic acid and caspase-3 activation, PARP cleavage, and sub-G0/G1 fraction of cell cycle increase. However, pretreatment with DDTG protected C6 glial cells from tunicamycin. Treatment with tunicamycin resulted in the increased the expression of GRP78 and CHOP protein and produced ROS generation. However, pretreatment with DDTG inhibited the ER stress pathway, including increase of the expression of GRP78, CHOP proteins in C6 glial cells treated with tunicamycin. Taken together, these data suggest that DDTG is able to protect C6 glial cells from tunicamycin with marked inhibition of ER stress.

• 한국토양환경학회지
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• 제5권2호
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• pp.23-31
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• 2000

본 연구의 목적은 휘발유, 등유, 경유로 복합 오염되어있는 환경시료에서 등유, 경유에 대한 효율적인 분리.정량 방법을 찾기 위하여 동일 유류의 경우 기준 n-alkane의 면적비는 농도에 관계없이 일정하다는 가설하에 이를 입증하기 위한 실험과 등유, 경유의 기준 peak의 선정을 위한 회수율 실험을 실시하였다. 가설의 입증은 등유의 경우 n-alkane의 기준 peak를 $C_{l3}$, $C_{l4}$, $C_{15}$로, 경유는 $C_{l6}$, $C_{l7}$로 각각 두고 이들 기준 피크에 대한 타 n-alkane의 상대 면적비를 구하여 농도가 다른 시료간에 상관성을 조사한 결과 모두 높은 유의성을 보여 동일 유류의 경우 기준 n-alkane에 대한 타 n-alkane의 면적비는 일정하다는 것이 증명되었다. 한편 회수율 실험은 휘발유, 등유, 경유가 일정농도로 혼합된 시료에서 등유, 경유의 기준 peak를 한 쌍으로 하여 이들 기준 피크별 n-alkane의 상대분포비를 적용하여 회수율(%)을 조사한 결과 등유- $C_{l3}$/경유- $C_{l6}$는 107.0$\pm$20.6/86.6$\pm$15.9, 등유- $C_{13}$/경유- $C_{16}$는 99.6$\pm$17.2/86.6$\pm$15.9, 등유- $C_{15}$ /경유- $C_{16}$는 73.9$\pm$14.4/86.6$\pm$15.9, 등유- $C_{13}$경유- $C_{17}$는 109.4$\pm$20.8/75.9$\pm$14.7, 등유- $C_{l4}$/경유- $C_{17}$는 107.4$\pm$17.9/75.9$\pm$14.7, 등유- $C_{15}$ /경유- $C_{17}$는 95.7$\pm$14.6/75.9$\pm$14.7 로 나타났다. 이상의 결과로 볼 때 등유와 경유의 기준 피크로 위에서 제시된 어떤 것을 사용하더라도 정량이 가능할 것으로 보이나 농도변화에 따른 표준편차가 가장 적은 등유- $C_{15}$ , 경유- $C_{l7}$을 기준 피크로 이용하는 것이 바람직 할 것으로 판단된다.된다. 판단된다.로 판단된다.된다. 판단된다.