• Journal of the Korean Ceramic Society
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• v.21 no.2
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• pp.113-120
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• 1984

In this study a comparative investigation for the effect of $K_2SO_4$ and $CaSO_4$ on the decomposition of $C_3S$ was made. When pure $C_3S$ which was synthesized in the laboratory was mixed with $K_2SO_4$ and oxides such as MgO $Al_2O_3$ and $Fe_2O_3$ and then reburned at the temperature range between 135$0^{\circ}C$ and 145$0^{\circ}C$ no decompo-sition occurred, But when $CaSO_4$ and $Fe_2O_3$ were added to $C_3S$ and then reburned at below 130$0^{\circ}C$ $C_3S$ was partly decomposed to $C_2S$and CaO composing $2C_2S$.$CaSO_4$ When $CaSO_4$ and $Al_2O_3$were added $C_3S$ was entirely decomposed to $C_2S$ and CaO at 1300~140$0^{\circ}C$ but it was not decomposed at 145$0^{\circ}C$.

• Korean Journal of Organic Agriculture
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• v.6 no.1
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• pp.99-108
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• 1997

The aim of this experiment was to investigate the effect of applying times of cattle slurry on dry matter yield of Orchardgrass, when cattle slurry applied at rates of 30m3(average mineral nitrogen fertilizer equivalent to 120kg) per ㏊ in different dressing times, such as S1(1st and 2nd growth), S2(1st and 3rd growth), S3(1st and 4th growth), S4(2nd and 3rd growth), S5(2nd and 4th growth) and S6(application for 3rd and 4th growth). The results were as follows. 1. The average annual yields of dry matter were produced 6.36~7.42 ton per ㏊ in 1995~1997 when cattle slurry applied at rates of 30m3(average mineral nitrogen fertilizer equivalent to 120kg) per ㏊ in different dressing times, especially these tendency were shown higher annual dry matter in S4 plot9application for 2nd and 3rd growth). Those were higher 2.48~3.54 tons or 1.22~2.28 tons per ㏊ than the yields from non-fertilizing or phosphrous and potassium fertilizing. 2. Relative yields of annual dry matter in cattle slurry application plots were 164(S2 plot)~191(S4 plot)% in comparing with non-fertilizing plot. 3. Dry matter yields according to cutting frequency were highest at the 2nd cut(1.50 ton) and were in the order 3rd cut(0.95 ton)>4th cut(0.75 ton)>1st cut(0.69 ton/㏊). Also, those of cattle slurry application plot per ㏊ were in the order 2nd cut(2.02~2.73 tons)>3rd cut(1.56~2.08 tons)>4th cut(1.07~1.68 tons)>1st cut(1.11~1.45 tons/㏊). 4. Relative yields of annual dry matter in cattle slurry application plots were 164~219, 161~210, 143~212 and 135~182% at the 3rd, 1st, 4th and 2nd cut, respectively in comparing with non-fertilizing plot. 5. The efficiencies of nitrogen on dry matter yield(kg DM/kg N) were 18.1, 21.3 and 34.5kg DM/kg N when cattle slurry applied to Orchardgrass at rates of 30m3 (average mineral fertilizer equivalent to 120 kg) per ㏊ in 1993, 1994 and 1995, respectively, especially these tendency were shown higher efficiencies in S4 plot(application for 2nd 3rd growth). On the other hand, those of the same level fertilization of mineral nitrogen were 43.8, 19.2 and 13.4 kg DM/kg N in 1993, 1994 and 1995, respectively.

• Journal of the Korean Ceramic Society
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• v.31 no.12
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• pp.1417-1422
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• 1994

Effect of MgO, CaSO4, and CaF2 addition on the formation of clinker minerals in portland cement have been investigated by measuring the amounts of free-CaO and C3S in the fired specimens and analyzing the Mg and S concentration in C3S and C2S. It was found that CaSO4 inhibited C3S formation but MgO addition offset this effect of CaSO4. MgO addition also enhanced the mineralizing effect of CaSO4+CaF2, resulting in the acceleration of C3S formation. It was suggested that Mg might inhibit the formation of sulphate compounds rim around C2S and thus C2S+CaOlongrightarrowC3S reaction was facilitated.

• Proceedings of the Optical Society of Korea Conference
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• 1991.06a
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• pp.98-101
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• 1991

The As2S3 thin film has a characteristics of optical modulation in both amplitude and phase. Since the As2S3 thin film can be used as a real-time reconfigurable optical filter, the fSDF filter can be optically fabricated on it. According to the modulation characteristics of the As2S3, the optimal fSDF filter recorded on this thin plate has the form of continuous amplitude and binary phase. Computer simulation and optical experiments on the optical pattern classification show that the As2S3 is suitable for the optical fSDF filter.

• Journal of the Korean Ceramic Society
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• v.30 no.1
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• pp.7-16
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• 1993

Effect of sulfate on the reactionof C3S formation in presence of clinker melt and its appearance in clinker were investigated, using (NH4)2SO4 and CaSO4 as sulfate sources. When (NH4)2SO4 and CaSO4 were added, both showed the similar results, 1.0wt% of sulfate could promoted the reaction of C3S formation, however for its content of more than 2.0wt%, the formation of C3S was prevented. Residual limit of sulfate to C3S formation is about 1.4wt%. Appearances of sulfate were C4A3l and CaSO4 in interstitial phase. For the addition of (NH4)2SO4 or CaSO4 of 20wt%~4.0wt%, C3S grains showed the hypertrophic growth. We might consider that, because sulfate reduced the surface tension and viscosity of the clinker melt, C3S crystals were precipitated below 140$0^{\circ}C$, and the crystlas of C3S were coalesced and linked in the same crystallographical direction with increasing temperature becuase of their rapid growth rate.

• Proceedings of the Optical Society of Korea Conference
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• 1990.02a
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• pp.162-166
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• 1990

Photoinduced anisotropy (PIA) in amorphous As2S3 (a-As2S3 ) thin film, deposited by vacuum evaporation, is investigated. PIA is induced by linearly polarized Ar+ laser beam (λ=514.5nm) and probed by weak Ar+ laser (λ=514.5nm) and He-Ne laser (λ=632.8nm) beam through the crossed analyzer. Keeping pump beam intensity constantly, rotation of pump beam polarization direction induces reorientation phenomina of anisotropic axis. Introducing directional factor into simplified 3-level system, which is used to analyze photodarkening phenomina, an analytical expression of PIA is derived. Temporal behavior of PIAand its reorientation phenomina are investigated andcompared with theory. In the experiment pump beam intensity is 100mW/$\textrm{cm}^2$ and thickness of a-As2S3 thin film is 3${\mu}{\textrm}{m}$. In those condition, time constant of photoinduced anisotropy obtained by method of least square curve fitting is 4.0$\times$10-2sec-1. The time constant of PIA we obtained is larger than that of photodarkening, 2.8$\times$10-2sec-1.

• Bulletin of the Korean Chemical Society
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• v.20 no.6
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• pp.648-652
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• 1999

Studies have been carried out on the unusual molecular nonrigidity of CoⅢ(PymS)3 and Cp* RhⅢ(PymS)2(PymS:2-mercaptopyrimidine). The crystal structure of CoⅢ(PymS)3 approximates to an octahedral mer isomer with 4-membered N-Schelating fashion. For Cp*RhⅢ(PymS)2, one PymS ligand bonds to the rhodium ion in an S-monodentate mode (Rh-S(2) = 2.366(1)Å) while the other ligand chelates to the metal ion in an N,S-bidentae mode (Rh-S(1)=2.414(1);Rh-N(1)=2.103(3)Å). Even though the conformations and configurations of both complexes are still retained in solution, an unusual nonrigidity for the protons of the PymS region is obsered in the solution. The broad proton signals of CoⅢ(PymS)3 exhibit a temperature-dependence in the range of -40∼40℃ with a free energy of activation ΔG=64.49kJ/mol(40℃). For Cp*RhⅢ(PymS)₂,such a fluxionality has been markedly observed in solution. This fluxional behavior can be explained in terms of "ligand tautomerism" in metal complexes containing potential tautomeric forms.

• Archives of Pharmacal Research
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• v.23 no.4
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• pp.353-359
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• 2000

${\alpha}_2$-Adrenoceptor antagonists, which can enhance synaptic norepinephrine levels by blocking feedback inhibition processes, are potentially useful in the treatment of disease states such. as depression, memory impairment, impotence and sexual dysfunction. (10bS)-1,2,3,5,6,10b-Hexahydropyrrolo[2,1-a]isoquinoline oxalate (YSL-3S) was evaluated in several in vitro biological tests to establish its pharmacological profile of activities as an ${\alpha}_2$-adrenoceptor antagonist. Saturation binding assay revealed that$^{3}[H]$rauwolscine bound to the $\alpha$$_2$-adrenoceptors with a Kd value of 6.3$\pm$0.5 nM and a Bmax value of 25l$\pm$39 fmol/mg protein in rat cortical synaptic membranes. Competitive binding assay showed that YSL-3S inhibited the binding of$^3[H]$rauwolscine (1 nM) in a concentration-dependent manner with a Ki value of 98.2$\pm$12.1 nM while it did not inhibit the binding of [$^3$H]cytisine (1.25 nM) to neuronal nicotinic cholinergic receptors. The Ki values of yohimbine, clonidine and norepinephrine for $^3[H]$rauwolscine binding were 15.8$\pm$1.0, 40.1$\pm$5.9 and 40.0$\pm$11.5 nM, respectively. In addition, the binding affinity of YSL-3S for ${\alpha}_2$-adrenoceptors was higher than that of its antipode and the racemic mixture. The functional activity of YSL-3S at the presynaptic ${\alpha}_2$-adrenoceptors was assessed using the prostatic portion of the rat vas deferens. Clonidine inhibited field-stimulated contractions of the vas deference in a dose-dependent manner. The presence of YSL-3S or yohimbine caused a parallel, rightward the dose-response curve of clonidine in a dose-dependent manner, indicating an antagonistic action at the presynaptic ${\alpha}_2$-adrenoceptors. The $pA_2$values of yohimbine and YSL-3S were 7.66$\pm$0.13 and 6.64$\pm$0.18, respectively. The results indicate that YSL-3S acts as a competitive antagonist at presynaptic ${\alpha}_2$ -adrenoceptors with a potency approximately ten times lower than yohimbine, but is devoid of binding affinity for neuronal nicotinic cholinergic receptors.

• Journal of the Korean Applied Science and Technology
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• v.35 no.2
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• pp.463-471
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• 2018

In this study, analyzed of changes resulting from the spread of carbon black in casein grafted water dispersed polyurethane using PPG. For this purpose, casein-grafted water-dispersed polyurethane and (PUD and CPUD's) samples were prepared and samples of CPCB's dispersed with carbon black were prepared. As a result of measuring the tensile strength using prepared samples, the tensile strength was increased to $3.01kgf/mm^2$ with CPUD3, which contains highly casein, in CPCB's tensile strength was measured as low as $2.54kgf/mm^2$ with increasing carbon black. Elongation was measured in 278% of PUD samples containing less casein, and CP3CB4 in CPCB's was measured as 157%. The abrasion resistance of the samples was 36.97 mg.loss for CPUD3 and 41.11 mg.loss for CP3CB4. The solvent resistance of the PUD 's sample and the CPCB' s sample were not changed.

• Journal of Ginseng Research
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• v.44 no.5
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• pp.725-737
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• 2020

Background: T-cell acute lymphoblastic leukemia (T-ALL) is a kind of aggressive hematological cancer, and the PI3K/Akt/mTOR signaling pathway is activated in most patients with T-ALL and responsible for poor prognosis. 20(S)-Ginsenoside Rh2 (20(S)-GRh2) is a major active compound extracted from ginseng, which exhibits anti-cancer effects. However, the underlying anticancer mechanisms of 20(S)-GRh2 targeting the PI3K/Akt/mTOR pathway in T-ALL have not been explored. Methods: Cell growth and cell cycle were determined to investigate the effect of 20(S)-GRh2 on ALL cells. PI3K/Akt/mTOR pathway-related proteins were detected in 20(S)-GRh2-treated Jurkat cells by immunoblotting. Antitumor effect of 20(S)-GRh2 against T-ALL was investigated in xenograft mice. The mechanisms of 20(S)-GRh2 against T-ALL were examined by cell proliferation, apoptosis, and autophagy. Results: In the present study, the results showed that 20(S)-GRh2 decreased cell growth and arrested cell cycle at the G1 phase in ALL cells. 20(S)-GRh2 induced apoptosis through enhancing reactive oxygen species generation and upregulating apoptosis-related proteins. 20(S)-GRh2 significantly elevated the levels of pEGFP-LC3 and autophagy-related proteins in Jurkat cells. Furthermore, the PI3K/Akt/mTOR signaling pathway was effectively blocked by 20(S)-GRh2. 20(S)-GRh2 suppressed cell proliferation and promoted apoptosis and autophagy by suppressing the PI3K/Akt/mTOR pathway in Jurkat cells. Finally, 20(S)-GRh2 alleviated symptoms of leukemia and reduced the number of white blood cells and CD3 staining in the spleen of xenograft mice, indicating antitumor effects against T-ALL in vivo. Conclusion: These findings indicate that 20(S)-GRh2 exhibits beneficial effects against T-ALL through the PI3K/Akt/mTOR pathway and could be a natural product of novel target for T-ALL therapy.