• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.60-60
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• 2008

We manufactured Liquid Crystal Polymer (LCP) and (1-x)$BaTiO_3-xSrTiO_3$(BST) ceramic composites and investigated dielectric properties to use as embedded capacitor in printed circuit boards and replace LTCC substrates. The dielectric properties of these composites are varied with volume fraction of BST and ratios of BT/ST. Dielectric constants are in the range of 3~28. In addition, we could get low TCC and High Q value that could not achieve in other ceramic-polymer composites. Especially, in composite with x=0.4 and 50vol% BST, the dieletric constant and Q-value are 27 and 300, respectively. And more TCC is -116~145ppm/$^{\circ}C$ in the temperature range of -55~$125^{\circ}C$. We think that this composites can be used high-Q substrate material like LTCC and embedded temperature compensation capacitor in printed circuit boards.

• 생약학회지
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• 제25권3호
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• pp.278-292
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• 1994

This study was attempted to investigate the effect of Machili Cortex extract(Machilus thunbergii Sieb. et Zucc. ) on digestive system in experimental animals. EtOH and MeOH extracts(E.E. and M.E.) were found to inhibit the charcoal transport rate in the small intestine of mice. E.E. exhibited the inhibition of spontaneous movement(motility) and tension in the ileum and colon strips of rabbit, and these actions were inhibited by action of acetylcholine. E.E. and M.E. given intraduodenaly(i.d.) exhibitied the significant decrease of gastric acid secretion in pylorus-ligated rats. E.E. and M.E. inhibited the formation of some experimental gastric ulcers(pylorus ligation-ulcer i.d., indomethacin-induced ulcer p.o. and aspirin-induced ulcer p.o. ) in rats, which are considered to relate to a protective action. E.E. and M.E. caused remarkable increase of bile excretion, compared with normal-control group, when adminstered through i.d., i.v. and p.o. The antibacterial activity against several intestinal microorganisms and other bacteria in vitro test was observed in the administration of E.E. and M.E.

• Natural Product Sciences
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• 제18권4호
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• pp.273-278
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• 2012

Further phytochemical investigation on the whole plant of Thyrsanthera suborbicularis, collected in Cambodia, led to kaempferol (1), vitexin (2), apigenin-7-O-neohesperidoside (3), chrysoeriol-7-O-${\beta}$-D-glucopyranoside (4), isorhamnetin 3-O-rutinoside (5), kaempferol-3-O-[${\alpha}$-L-rhamnopyranosyl-(13)-${\alpha}$-L-rhamnopyranosyl-(16)-${\beta}$-D-galactopyranoside (6), kaempferol-3-O-${\alpha}$-L-rhamnopyranosyl(12)-O-[${\alpha}$-L-rhamnopyranosyl (16)]-${\beta}$-D-glucopyranoside (7), kaempferol-3-O-[6"-O-(E)-p-coumaroyl]-${\beta}$-D-glucopyranoside (8), kaempferol-3-O-[6"-O-(E)-p-coumaroyl]-${\beta}$-D-galactopyranoside (9), and amentoflavone (10). All the structures were confirmed by the interpretation of NMR (1D and 2D) and MS data, and comparison with the published values. Of the isolated compounds 1 - 10, compounds 8 and 10 displayed the inhibitory activity against NO production in LPS-induced Raw 264.7 cells with $IC_{50}$ values, 3.56 and $15.73{\mu}M$, respectively.

• 대한수학회보
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• 제37권3호
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• pp.429-435
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• 2000

Our main goal is to show that if there exist Jordan derivations D, E and G on a noncommutative 2-torsion free prime ring R such that$(G^2(x)+E(x))D(x)=0\ or\ D(x)(G^2(x)+E(x))=0\ for\ all\ x\inR$, then we have D=o or E=0, G=0.

• 한국기술혁신학회:학술대회논문집
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• 한국기술혁신학회 2004년도 춘계학술대회
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• pp.48-56
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• 2004

To perform R&D program, it is necessary to invest input factor(I/F). And these factor are converted to output factors(O/F) at the end of R&D program. Pee. reviewers evaluate output factors and produce evaluation grades(E/G). This paper try to analyze the relationship to I/F, O/F and E/G, According to the analysis results, the relation between I/F and E/G is as weak as the relation between O/F and E/G. The strength of relationship is relatively very strong in the relation between I/F and O/F

• 한국세라믹학회지
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• 제30권4호
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• pp.289-298
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• 1993

Properties in terms of the variation of the glass compositions, which were density (p), molar volume(Vm), atom/ion packing density (Dp), refractive index (nD), transformation temperature (Tg), dilatometric softening point (Td), thermal expansion coefficient (α), Young's modulus (E), and knoop hardness (KHN) were investigated in CaO-SiO2 glasses and CaO-P2O5-SiO2 glasses containing less than 10mole% of P2O5. Those properties were measured by density measurement kit, Abbe refractometer, dilatometer, ultrasonic pulse echo equipment, and micro hardness tester. When CaO content was increased in CaO-SiO2 glasses, p, Dp, nD, Tg, Td, α, E and KHN were increased, while Vm was decreased. When P2O5 was added to the CaO-SiO2 glasses with constant CaO/SiO2 ratio as 1.07, p, Dp, nD, Tg, Td, α, E and KHN were decreased, while Vm was increased. When the amount of P2O5 in glasses was kept constant, the changes of the properties with variation of CaO content in the CaO-P2O5-SiO2 glasses were very similar to those of CaO-SiO2 glasses. These phenomena could be explained by the structural role of P2O5 in the CaO-P2O5-SiO2 glasses, which was polymerization of siicate structures and resulted in [PO4] monomer structure in glasses. Due to this structural characteristics, the bond strength and packing density were changed with compositions. Proportional relationships between 1) np and Dp, 2) Tg, Td, α and CaO content, 3) E and Vm-1, and 4) KHN and P2O5 content were evaluated in this investigation.

• 대한화학회지
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• 제45권4호
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• pp.312-317
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• 2001

7'-Aldehyde-nucleoside 유사체(2a, 2c)을 6-N-benzoyl-2',3'-O-isopropylideneadenosiner과 uridine으로부터 합성하였다. 2와 Wittig reagent인 ethoxycarbonylmethylene을 축합시켜 ethoxycarbonyl group을 갖는 탄소수를 증가시킨 공액 이중 결합을 지닌 nucleosi de 유사체, ethyl-1',5',6',7',8'-pentadeoxy-1'-(adenin-9-yl)-$\beta$-D-ribo-nnona-5'(E).7'(E)-dienofuranuronate(4b), ethyl-1',5',6',7',8'-pentadeoxy-1'-(uracyl-1-yl)-$\beta$-D-ribo-nona-5'(E),7'(E)-dienofuranuronate(4c)을 얻었다. 또한 2와 CBr4, Ph3P을 반응시켜 공액 이중 결합을 지닌 9-[8',8'-dibromo-5',6',7',8'-tetradeoxy-$\beta$-D-ribo-octa-5'(E),7'(E)-diene]nucleosides (6b,6c) 유사체를 각각 합성하였다.

• 약학회지
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• 제58권5호
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• pp.314-321
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• 2014

Cibotii Rhizoma, the dried rhizome of Cibotium barometz J. Smith (C. barometz), has long been used to treat bone or nervous system disorders. In this regard, we isolated three main phenolic compounds, onitin-4-O-${\beta}$-D-glucopyranoside (1), irisdichototins E & F epimeric mixture (2), and protocatechuic acid (3) from C. barometz methanol extract. In addition, we screened their antioxidative activities by DPPH, ABTS radical, and superoxide scavenging assays. Among these three compounds, irisdichototins E & F and protocatechuic acid showed strong antioxidant activities. Also, the antioxidant activities of the C. barometz extracts were proportional to the contents of irisdichototins E & F and protocatechuic acid, thus these two phenolic compounds could be main active compounds of C. barometz. In addition, onitin-4-O-${\beta}$-D-glucopyranoside is considered as a marker compound of C. barometz because this compound is specifically contained in C. barometz which belongs to Pteridophyta order. A rapid analysis method for the simultaneous determination of phenolic compounds was also developed by UPLC (Ultra Performance Liquid Chromatography). Using the developed method, the two active compounds (irisdichototins E & F and protocatechuic acid) and a marker compound (onitin-4-O-${\beta}$-D-glucopyranoside) were successfully quantified in 14 commercial samples that were collected from different regions.

• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1341-1345
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• 2007

The surface chemistry of D2O dosed Zircaloy-4 (Zry-4) surface followed by Ar-ion bombardment and annealing was studied by means of X-ray photoelectron spectroscopy (XPS) and Ultraviolet photoelectron spectroscopy (UPS). In the XPS study, Ar-ion bombardment caused decrease of the oxygen on the surface region of Zry-4 and therefore led to change the oxidation states of the zirconium from oxide to metallic form. In addition, oxidation states of zirconium were changed to lower oxidation states of zirconium due to depopulation of oxygen on the surface region by annealing. Up to about 787 K, the bulk oxygen diffused out to the subsurface region and after this temperature, the oxygen on the surface of Zry-4 was depopulated. UPS study showed that the valence band spectrum of the D2O exposed Zry-4 exhibited a dominant peak at around 13 eV and no clear Fermi edge was detected. After stepwise Ar+ sputtering processes, the decrease of the oxygen on the surface of Zry-4 led to suppress the dominant peak around 13 eV, the peak around 9 eV and develop a new peak of the metallic Zr 4d state (20.5-21.0 eV) at the Fermi level.

• 한국전기전자재료학회논문지
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• 제17권1호
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• pp.112-117
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• 2004

$Y_2$$_{-x}$G $d_{x}$ $O_3$:E $u^{3+}$(x=0.0, 0.3, 0.6, 1.0, 1.4) luminescent thin films have been grown on Si (100) substrates using pulsed laser deposition. The films grown under different deposition conditions have been characterized using microstructural and luminescent measurements. The crystallinity, the surface morphology and photoluminescence (PL) of the films are highly dependent on the amount of Gd. The photoluminescence (PL) brightness data obtained from $Y_2$$_{-x}$G $d_{x}$ $O_3$:E $u^{3+}$ films grown under optimized conditions have indicated that Si (100) is one of promised substrates for the growth of high quality $Y_2$$_{-x}$G $d_{x}$ $O_3$:E $u^{3+}$ thin film red phosphor. In particular, the incorporation of Gd into $Y_2$ $O_3$ lattice could induce a remarkable increase of PL. The highest emission intensity was observed with $Y_{1.35}$G $d_{0.60}$ $O_3$: $E^{3+}$, whose brightness was increased by a factor of 1.95 in comparison with that of $Y_2$ $O_3$:E $u^{3+}$ films.3+/ films.films.lms.