• Elastomers and Composites
• /
• v.51 no.1
• /
• pp.63-67
• /
• 2016

Poly(ethylene-co-vinyl acetate) (EVA) was pyrolyzed to eliminate acetic acid of VA unit using off-line pyrolysis, and the deacetylated EVA was analyzed infrared spectroscopy (IR) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). EVA film for deacetylation was prepared by solution casting on aluminum foil and it was pyrolyzed at low temperature of $300^{\circ}C$ in the off-line pyrolysis apparatus. After deacetylation, carbon-carbon double bond (C=C) was formed by 1,2-elimination of the VA unit in the EVA backbone. Most of C=C bonds were trans-1,4-unit and 1,2-unit was also observed. Presence of the 1,2-unit in deacetylated EVA indicates that terminal or branch VA units exist in the raw EVA. Py-GC/MS chromatogram of deacetylated EVA displayed much smaller acetic acid and much more abundant other pyrolysis products than that of raw EVA, which means that the pyrolysis efficiency and separation condition were improved.

• Proceedings of the Ginseng society Conference
• /
• 1988.08a
• /
• pp.25-27
• /
• 1988

To assess the effect of Panax ginseng on the detoxification of ethanol. we examined its effect on blood ethanol clearance in both man and experimental animals and on the rate of ethanol oxidation to carbon dioxide in experimental animals. Fourteen healthy male volunteers were subject to studies. The blood alcohol level in the test group receiving ginseng extract (3g/kg b.w.) along with alcohol (70g/65kg b.w.) was about $35\%$ lower than their control levels at 40 min after ethanol intake. When the blood alcohol level was compared on individual bases. blood alcohol concentrations in 10 subjects ranged from 32 to $51\%$ lower than their control values. The remaining 4 subjects appeared to have a high tolerance level. In experimental animals. the blood alcohol clearance was also much faster in test animals receiving ginseng along with ethanol. The rate of ethanol elimination was determined by the amount of $^{14}CO_2$ in exhaled air following the administration of [$^{14}C$] ethanol. During the first 7 1/4 hr (Phase I) after the ethanol administration. the $CO_2$ output was greater in test animals receving ginseng along with ethanol. whereas from beyond 7 1/4 hr to the near end (Phase II). the $CO_2$ output in control animals was over twice that in test animals. The present studies clearly demonstrate that ginseng promotes the overall metabolism of ethanol. resulting in an enhanced blood alcohol clearance and alcohol elimination.

• YAKHAK HOEJI
• /
• v.22 no.4
• /
• pp.215-218
• /
• 1978

It is known that hydantoin derivative can be synthesized according to the method of Bucherer-Bergs, which employs the interaction of the carbonyl compounds with potassium cyanide and ammonium carbonate in dilute alcohol solution. In a converting study of .alpha.-dietylaminoacetophenone with KCN and ($NH_{4})_{2}CO_{3}$ to hydantoin, the attempted 5-diethylaminomethyl-5-phenylhydantoin was not formed. In this reaction diethylaminomethly group was unexpectedly eliminated and 5-phenylhydantoin was obtained, instead of the anticipated compound.

• Horticultural Science & Technology
• /
• v.28 no.5
• /
• pp.864-870
• /
• 2010

This study was conducted to determine the effects of foliage plants on reducing indoor carbon dioxide ($CO_2$). Five foliage plants such as $Hedera$ $helix$ L., $Ficus$ $benjamina$ L., $Pachira$ $aquatica$, $Chamaedorea$ $elegans$, and $Ficus$ $elastica$ were selected and cultivated in two different growth medium (peatmoss and hydroball). Each plant was placed in an airtight chamber and then treated with the combinations of two different $CO_2$ concentrations (500 or 1,000 ppm) and two different light intensities (50 or $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). The change of $CO_2$ concentration (ppm) in the airtight chamber during day and night was measured and then converted into the photosynthetic rate (${\mu}mol\;CO_2{\cdot}m^{-2}{\cdot}s^{-1}$). As the results, each foliage plant reduced $CO_2$ level in the airtight chamber for one hour by photosynthesis. $Pachira$ $aquatica$ and $Ficus$ $elastica$ absorbed $CO_2$ more effectively compared to the other plants. The plants exposed to higher $CO_2$ concentration (1,000 ppm) and higher light intensity ($200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) showed more effective $CO_2$ elimination rate and photosynthetic rate. The plants that have wide leaves and big leaf areas such as $Pachira$ $aquatica$, $Hedera$ $helix$ L.,and $Ficus$ $elastica$ showed higher photosynthetic rate than the other plants that have smaller leaves. Released $CO_2$ concentration by respiration of the plants during the night was very low compared to the absorbed $CO_2$ concentration by photosynthesis during the day. There was no significant difference between peatmoss and hydroball medium on reducing $CO_2$ concentration and increasing photosynthetic rate. In conclusion, this study suggested that foliage plants can effectively eliminate indoor $CO_2$. Optimum environmental control in relation to photosyntheis and usage of right indoor foliage plants having lots of leaves and showing active photosynthesis even under low light intensity like indoor light condition would be required to increase the elimination capacity of indoor $CO_2$.

• Environmental Engineering Research
• /
• v.11 no.4
• /
• pp.232-240
• /
• 2006

Polychlorinated naphthalenes (PCNs) formed along with dibenzo-p-dioxin and dibenzofuran products in the slow combustion of dichlorophenols (DCPs) at $600^{\circ}C$ were identified. Each DCP reactant produced a unique set of PCN products. Major PCN congeners observed in the experiments were consistent with products predicted from a mechanism involving an intermediate formed by ortho-ortho carbon coupling of phenoxy radicals; polychlorinated dibenzofurans (PCDFs) are formed from the same interemediate. Tautomerization of the intermediate and $H_2O$ elimination produces PCDFs; alternatively, CO elimination to form dihydrofulvalene and fusion produces naphthalenes. Only trace amounts of tetrachloronaphthalene congeners were formed, suggesting that the preferred PCN formation pathways from chlorinated phenols involve loss of chlorine. 3,4-DCP produced the largest yields of PCDF and PCN products with two or more chlorine substituents. 2,6-DCP did not produce tri- or tetra-chlorinated PCDF or PCN congeners. It did produce 1,8-DCN, however, which could not be explained.

• Economic and Environmental Geology
• /
• v.48 no.1
• /
• pp.25-39
• /
• 2015

$CO_2$ geological storage plays an important role in reduction of greenhouse gas emissions, but there is a lack of research for CCS demonstration. To achieve the goal of CCS, storing $CO_2$ safely and permanently in underground geological formations, it is essential to understand the characteristics of them, such as total storage capacity, stability, etc. and establish an injection strategy. We perform the impedance inversion for the seismic data acquired from the Ulleung Basin in 2012. To review the possibility of $CO_2$ storage, we also construct porosity models and extract attributes of the prospects from the seismic data. To improve the quality of seismic data, amplitude preserved processing methods, SWD(Shallow Water Demultiple), SRME(Surface Related Multiple Elimination) and Radon Demultiple, are applied. Three well log data are also analysed, and the log correlations of each well are 0.648, 0.574 and 0.342, respectively. All wells are used in building the low-frequency model to generate more robust initial model. Simultaneous pre-stack inversion is performed on all of the 2D profiles and inverted P-impedance, S-impedance and Vp/Vs ratio are generated from the inversion process. With the porosity profiles generated from the seismic inversion process, the porous and non-porous zones can be identified for the purpose of the $CO_2$ sequestration initiative. More detailed characterization of the geological storage and the simulation of $CO_2$ migration might be an essential for the CCS demonstration.

• Journal of Electrical Engineering and Technology
• /
• v.11 no.2
• /
• pp.393-404
• /
• 2016

In this paper, a carrier-based pulse with modulation (PWM) strategy for three-phase three-level inverter is dealt with, which can keep the common mode voltage constant with minimized switching frequency. The voltage gain and the switching frequency in overall operating ranges including overmodulation are investigated and the analytic equations are presented. Finally, the leakage current reduction effect is confirmed by carrying out simulation and experiment. It will be pointed out that the leakage current cannot be perfectly eliminated because of the dead time.

• YAKHAK HOEJI
• /
• v.41 no.3
• /
• pp.335-344
• /
• 1997

The absorption, distribution and excretion of $^{14}C$ labeled YH1885 {5,6-Dimethyl-2(4-fluorophenylamino)-4-(1-methyl-1,2,3,4-tetrahydroisoquinolin-2-yl)pyrimidine hydroc hloride), a new proton pumpinhibitor, were investigated in rats after a single administration of $^{14}C$-YH1885. 1. After intravenous administration of 5mg/kg, the blood level of radioactivity declined in a biphasic fashion with the mean terminal elimination half-life of 12.4hr. 2. After oral administration of 20mg/kg, the maximum blood level of radioactirity was reached at 4.0hr in female rats. The blood level of radioactivity-time profiles in male and female rats were similar, and the absorptionof $^{14}C$-YH1885 was not affected by food. 3. Appproximately 89% and 1% of radioactivity of the total dose were excreted in feces and urine, respectively. 4. Biliary excretion of radioactivity was 47.9% of the dose. Enterohepatic circulation of radioactivity was 49.6%. 5. Radioactivity was excreted maily into feces via bile. 6. The concentration of radioactivity in most tissues reached the peak level at 4.0hr after dosing, and then declined. Autoradiograms of male rats showed that the radioactivity levlels in the fat, harder's gland, liver and G-Itract were higher than those in the other tissues and the elimination of radioactivity from fat and liver was slow. 7. Autoradiograms of a pregnant rat showed that radioactivity was transferred to mammary gland, placenta and fetus. The radioactivity level in the mammary gland was higher than that in the blood.

• Journal of Pharmaceutical Investigation
• /
• v.27 no.1
• /
• pp.57-64
• /
• 1997

$Amino-{\beta}-lactam$ antibiotics are absorbed by the dipeptide transporter in the small intestine. These uptakes are coupled to a proton influx. The inward proton gradient is partly induced by the $Na^+/H^+$ exchanger and calcium ion is involved in control of this antiport. Interaction between ampicillin which is one of the $Amino-{\beta}-lactam$ antibiotics and nifedipine which is one of calcium channel blocking agents was studied in rats in vivo and with rabbit jejunum mounted on the Sweetana/Grass diffusion cells in vitro. Bioavailability of ampicillin was increased significantly when nifedipine was co-administered orally in rats. There were no differences in the distribution phase and the elimination phase when ampicillin was given either alone or with nifedipine intravenously. Conditions for in vitro experiments were determined. The lift rate of $O_2/CO_2$ gas was controlled to 3 bubbles/sec and ampicillin was stable in the Kreb's buffer at pH 6.0. Absorption of ampicillin was the greatest when the completely-stripped serosal membrane was used. Transport of ampicillin from mucosal to serosal side in the rabbit jejunum was enhanced by 32% in the presence of nifedipine (p=0.059). Above results suggest that nifedipine might increase the plasma level of ampicillin via the improved absorption in the intestine rather than the reduction in the elimination or/and alteration in the distribution.

• Journal of Pharmaceutical Investigation
• /
• v.26 no.1
• /
• pp.29-32
• /
• 1996

In vivo and in vitro skin permeation of $recombinant^{125}$ I-EGF through normal, stripped and the first degree burn skin were studied. The in vitro skin permeation rate through the first degree burn skin $(296\;cpm/cm^2/hr)$ and the stripped skin $(1131\;cpm/cm^2/hr)$ were 3.5 times and 13 times higher, respectively, as compared with the one through normal skin. In vivo absorption study with the first degree burn skin, the peak concentration of EGF in the skin was achieved at 1-3 hr and decreased afterward up to 8 hr with an elimination constant of $1.31{\times}10^{-3}\;g/ml/hr$. To investigate the higher elimination rate of EGF in burn skin, binding and metabolism studies were conducted. No significant metabolism of EGF in burn skin $(100^{\circ}C,\;5-second\;burning)$ was observed. With the presence or unlabelled-EGF $^{125}I-EGF$ permeation through the burn skin showed higher permeation rate than the one without unlabelled-EGF. The result nay indicate that EGF-receptor binding play a role in determining the skin permeation rate.