• Korean Journal of Weed Science
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• v.17 no.2
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• pp.185-191
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• 1997

This experiment was conducted to determine the selective mechanism of cyhalofop-butyl ester on uptake, traslocation, and metabolism of the herbicide in both rice and Echinochloa crus-galli. Uptake and translocation of $^{14}C$-cyhalofop-butyl ester was higher in E. crus-galli than rice when treated to shoot. $^{14}C$-uptake by root of E. crus-galli increased rapidly at 30 minute after treatment and reached the maximum at 12 hoots after treatment. After that, uptake was leveled off. Uptake pattern in rice root was not significantly affected by the duration of herbicide treatment. In E. crus-galli, the absorbed $^{14}C$-cyhalofop-butyl ester seemed to be rapidly metabolized into free acid and the content of changed free acid was higher than rice.

• Applied Biological Chemistry
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• v.34 no.4
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• pp.299-306
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• 1991

When $[U-^{14}C]$ 3,3', 4,4'-tetrachloroazobenzene$([U-^{14}C]\;TCAB)$ was added to the $MM_2$ medium as a sole carbon source for the isolated microorganisms and incubated, some radioactive metabolites were detected by autoradiography. No $^{14}CO_2$ was evolved from $[U-^{14}C]\;TCAB$ which was added as a sole carbon source to an organic matter-free soil inoculated by the isolates, wetted with the $MM_2$ salt medium, and incubated at $30^{\circ}C$. One of the metabolites in pure culture of Achromobacter group VD, which was isolated and identified, was tentatively identified as a compound of m/z 250 by means of GC/MS. The possible pathways for its formation are thought to include dechlorination from the TCAB structure, hydroxylation, ortho fission of the two benzene rings, and reduction of the resulting carboxyl group.

• Journal of the Korean Magnetics Society
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• v.4 no.2
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• pp.126-129
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• 1994

In order to invetigate the effect of Pr additive on the magnetostriction of amorphous Fe-B alloys, amorphous $Fe_{86-x}B_{14}Pr_{x}(2{\leq}x{\leq}8\;at.%)$ alloys were prepared by a rapid solidification process. As the Pr content increased in the as-prepared amorphous $Fe_{84}B_{14}Pr_{2}$ alloy annealed at $300^{\circ}C$ for 2 hr increased to 70 ppm. Ac power loss and permeability$(f=50\;kHz,\;B_{m}=0.1\;T)$ of the annealed amorphous $Fe_{84}B_{14}Pr_{2}$ alloy were 15 W/kg and $5.5{\times}10^{3}$, respectively.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.461-467
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• 2012

Developmental characteristics of Geocoris pallidipennis were investigated at a constant temperature ($20{\pm}1$, $25{\pm}1$, $30{\pm}1$, $35{\pm}1$, $37.5{\pm}1$ and $40{\pm}1^{\circ}C$), under long day illumination 16:8 (L:D) and constant relative humidity ($80{\pm}10%$). From egg to adulthood, the lower developmental threshold and the effective accumulative temperature were $14.8^{\circ}C$ and 399.1 day-degree, respectively. The experimental results at $35^{\circ}C$ were as follows. The egg period was 5.6 days (hatchability: 81.1%) and the nymphal period was 14.3 days (1st: 3.2, 2nd: 2.2, 3rd: 2.7, 4th: 2.7, 5th: 3.6). Female longevity was 33.8 days and the oviposition period was 29.2 days. Total egg production was 111.2 eggs and the maximum daily egg production was 14.8 eggs (in 7th days). However, although some eggs and nymphs developed at $37.5^{\circ}C$, G. pallidipennis could not develop at $40^{\circ}C$, The total egg production at $40^{\circ}C$ was only 22.1 eggs. When G. pallidipennis was fed on Bemisia tabaci pupae, daily prey consumption by nymphs (1st, 3rd and 5th) and adults was 1.9, 7.3, 18.7 and 29.5, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.291-298
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• 1984

The extracted hagfish (Eptatretus burgeri) flesh lipid was separated into following fractions by column chromatography on Bio-beads SX-2 and Sephadex LH-20 prior to gab chromatographic analysis of their fatty acid compositions: polar lipid, triglyceride and free fatty acid. The major fatty acids of total lipid and triglyceride in hagfish were $C_{16:0},\;C_{16:1},\;and\;C_{18:1}$. The ratio of $C_{18:0}/C_{18:1}$ in the total lipid and triglyceride of hagfish was 0.1. The polar lipid of the hagfish muscle was mainly composed of phosphatidyl choline ($65.5\%$) and phosphatidyl ethanolamine ($28.0\%$). The triglyceride obtained was fractionated into four fractions by HPLC on the basis of partition numbers. Both the fatty acid composition and triglyceride composition on the basis of the total carbon number in the acyl chains of the triglyceride were analysed by the GLC. From the information obtained on triglyceride compositions based on the total carbon number by GLC and the partition number by HPLC and fatty acid composition by GLC, the combination of fatty acid in each triglycerides was estimated. A computer was used for estimation of the fatty acid combination in the triglyceride because hagfish lipid triglyceride was composed of various kinds of fatty acids. Fortyfour kinds of triglyceride were estimated. The major triglycerides in hagfish flesh lipid were found to those of ($1{\times}C_{16:0},\;2{\times}C_{18:1};\;13.5\%$), ($1{\times}C_{16:0},\;1{\times}C_{18:0},\;1{\times}C_{18:1};\;7.2\%$), ($1{\times}C_{16:1},\;2{\times}C_{18:1};\;5.4\%$), ($2{\times}C_{16:0},\;1{\times}C_{22:5};\;5.2\%$), ($1{\times}C_{14:0},\;2{\times}C_{18:1};\;4.5\%$), ($2{\times}C_{18:1},\;1{\times}C_{22:5};\;3.6\%$), ($1{\times}C_{14:0},\;1{\times}C_{18:0},\;1{\times}C_{18:1};\;2.7\%$) and ($1{\times}C_{14:0},\;1{\times}C_{16:0},\;1{\times}C_{18:2};\;2.2\%$).

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.1295-1297
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• 1996

CCITT G.721, G.723 standard ADPCM algorithm is implemented by using TI's fixed point DSP start kit (DSK). ADPCM can be implemented on a various rates, such as 16K, 24K, 32K and 40K. The ADPCM is sample based compression technique and its complexity is not so high as the other speech compression techniques such as CELP, VSELP and GSM, etc. ADPCM is widely applicable to most of the low cost speech compression application and they are tapeless answering machine, simultaneous voice and fax modem, digital phone, etc. TMS320C50 DSP is a low cost fixed point DSP chip and C50 DSK system has an AIC (analog interface chip) which operates as a single chip A/D and D/A converter with 14 bit resolution, C50 DSP chip with on-chip memory of 10K and RS232C interface module. ADPCM C code is compiled by TI C50 C-compiler and implemented on the DSK on-chip memory. Speech signal input is converted into 14 bit linear PCM data and encoded into ADPCM data and the data is sent to PC through RS232C. The ADPCM data on PC is received by the DSK through RS232C and then decoded to generate the 14 bit linear PCM data and converted into the speech signal. The DSK system has audio in/out jack and we can input and out the speech signal.

• Bulletin of the Korean Chemical Society
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• v.14 no.5
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• pp.546-548
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• 1993

The discrete structure of substituted 9-benzonorbornenyl cation 3a and 3c was studied using the empirical ${\Delta}$J equation which was developed by Kelly and coworker$^5$. The ${\Delta}$J values of substituted 9-benzonorbornenyl cations were obtained from p-methyl-6,7-dimethyl benzonorbornen-9-yl (3a) and 9-methyl-6,7-dimethyl benzonorbonen-9-yl (3c) cations under stable ion conditions, and were compared with those of the corresponding ketone analog; these cations were generated by dissolving the corresponding carbinols in superacid at -120$^{\circ}$C and the nmr spectra taken at -60$^{\circ}$C~-90$^{\circ}$C. The ${\Delta}$J values are 8.7 Hz for the bridgehead carbons in cation 3c and 3.1 Hz for cation 3b. The ${\Delta}$J values at C5,8 in fused benzene ring are 14.3 Hz for cation 3c and 8.7 Hz for cation 3a. The excellent correlation of the ${\Delta}$J values with 1$^9F$ chemical shifts of p-fluorophenyl-6,7-dimethylbenzonorbornenyl cation (3d) indicate that ${\Delta}$J value is a reliable probe to charge density at adjacent cationic carbon. These NMR parameters strongly support that the symmetrically ${\pi}$-bridged nonclassical structure (type 2) of substituted 9-benzonorbornenyl cations in stable ion conditions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.3
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• pp.231-238
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• 2010

The Induction of regeneration and maturation in the free-living gametophytes of Ecklonia stolonifera Okamura was studied at four temperatures (5, 10, 15, and $20^{\circ}C$), four levels of irradiance (5, 10, 20, and 40 ${\mu}mol\;m^{-2}s^{-1}$) and three photoperiods (14:10, 12:12, and 10:14 h L:D). Female gametophyte fragments were maintained in active regeneration without reaching sexual maturity under $5{\sim}10^{\circ}C$, 10 ${\mu}mol\;m^{-2}s^{-1}$, 10:14 h (L:D), whereas the conditions for male gametophytes were slightly different at $20^{\circ}C$, 40 ${\mu}mol\;m^{-2}s^{-1}$, 10:14 h (L:D). The sexual maturation of female and male gametophytes was facilitated at $15^{\circ}C$, 20 ${\mu}mol\;m^{-2}s^{-1}$, 14:10 h (L:D). These results provide basic information for controlling the regeneration and maturation of the free-living gametophytes for artificial seed production of E. stolonifera.

• 보존과학연구
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• s.23
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• pp.197-214
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• 2002

It is very important to determine the age of the Cultural Properties in archeology. In about 1950, W.F. Libby and a team of scientists at the University of Chicago developed the Radiocarbon Dating technique. Radiocarbon($^14$C) Dating is probably one of the most widely used and best known absolute dating methods. Radiocarbon ages are conventionally specified to the year 1950. This year is 0 BP year. BP is the initial of Before Present. The $^14$C within an organism is continually decaying into stable carbon isotopes. When $^14$C decays, it emits a $\beta$ - particle with an energy content of 156 KeV and becomes 14N. Only the $\beta$ - particle is detected by Liquid Scintillation Counting. $^14$C has a half life of 5730 years. It has been used to date samples as old as 50,000 years. Radiocarbon determinations can be obtained on organic material : wood, charcoal, shell, etc. The results of radiocarbon dating using Benzene Synthesizer and Liquid Scintillation Counter are KCP539 $4030\pm60$BP year, KCP540 $3980\pm60$BP year, KCP575 $4870\pm50$, KCP576 $100\pm50$BP year, KCP577 $130\pm50$BP yea and KCP578 $210\pm70$BP year.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.3
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• pp.337-343
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• 1997

Antiulcer effects of YH1238 and YH1885 were determined in the isolated gastric cells from human and rabbit stomach. Intracellular accumulation of $[^{14}C]-aminopyrine\;and\;[^{14}C]-glucose$ oxidation were used as indicators of acid secretory ability of the gastric cells. Unstimulated and stimulated gastric cells with dibutyryl cAMP$(10^{-3}M)$ were used and the inhibitory effects of YH1238 and VH1885 on acid secretion were compared with known proton pump inhibitors such as omerrazole and SK&F 96067. Dibutyryl cAMP stimulated the $[^{14}C]-aminopyrine$ accumulation and $[^{14}C]-glucose$ oxidation, which were inhibited by YH1238, YH1885, SK&F 96067 and omeprazole. Inhibitory effects of YH1238, YH1885 and omeprazole on $[^{14}C]-aminopyrine$ accumulation in stimulated gastric cells were more potent than that of SK&F 96067 at the concentration of $10^{-5}M$. It is suggested that the reversible proton pump inhibitors YH1238 and YH1885 would be effective antiulcer agents.