• Korean Journal of Optics and Photonics
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• v.1 no.1
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• pp.33-39
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• 1990

By developing a computer simulation code for discharge excited KrF excimer laser, we analyzed mainly the effects of buffer gas for the $KrF^*$ formation. the $KrF^*$ relaxation. and the absorption of the laser radiation. The $KrF^*$ formation efficiency were found to be 7.5%, 19% and the $KrF^*$ relaxation kinetic reactions were found to be 45%, 30% at the charging voltage of 30 KV and He. Ne buffer gas. respectively. But the absorption of the 248 nm laser radiation were less than 10% by the buffer gas.er gas.

• Archives of Pharmacal Research
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• v.24 no.3
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• pp.207-210
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• 2001

A fully automated high performance liquid chromatography with column-switching was developed for the simultaneous determination of KR60436, a new reversible proton pump inhibitor, and its active metabolite O-Demethyl-KR60436 from rat plasma samples. Plasma sample (50$\mu$l) was directly introduced onto a Capcell Pak MF Ph-1 column ($10{\times}4$ mm I.D.) where primary separation was occurred to remove proteins and concentrate target Substances Using acetonitrile-Potassium Phosphate (PH 7, 0.1 M) (2 : 8, v/v). The drug molecules eluted from MF Ph-1 column were focused in an intermediate column ($10{\times}2$ I.D.) by the valve switching step. The substances enriched in intermediate column were eluted and separated on a Vydac 218MR53 column ($250{\times}3.2$ I.D.) using acetonitrilepotassium phosphate (pH 7, 0.02 M) (47:53, v/v) at a flow rate of 0.5 ml/min when the valve status was switched back to A position. The method showed excellent sensitivity (detection limit of 2 ng/ml) with small volume of samples ($50{\mu}$l), good precision and accuracy, and speed (total analysis time 24 min) without any loss in chromatographic efficiency. The response was linear ($r^2{\geq}0.797$) over the concentration range of 5-500 ng/ml.

• The Plant Pathology Journal
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• v.21 no.4
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• pp.361-368
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• 2005

A Korean isolate of Pepper mild mottle virus (PMMoV-Kr) was isolated from a diseased hot pepper plant and its biological and molecular properties were compared to that of PMMoV-J and PMMo V -So The genomic RNA of PMMoV-Kr consists of 6,356 nucleotides. The nucleotide and amino acid sequences identities of four viral proteins and two noncoding regions among PMMoV-Kr, PMMoV-S and PMMoV-J were $96.9\%\;to\;100.0\%\;and\;97.5\%\;to\;98.6\%$, respectively. Full-length cDNA amplicon of PMMoV-Kr was directly amplified by RT-PCR with a set of 5'-end primer anchoring T7 RNA promoter sequence and 3'-end virus-specific primer. Capped transcript RNAs from the full-length cDNA clone were highly infectious and caused characteristic symptoms of wild type PMMoV when mechanically inoculated to systemic host plants such as Nicotiana benthamiana and pepper plants.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.217.2-217.2
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• 2003

A liquid chromatography-tandem mass spectrometric (LC/MS/MS) method was developed for the determination of a new anti-angiogenic drug KR-31831 in rat plasma. KR-31831 and internal standard, KR-31543 were extracted from rat plasma with dichloromethane at basic pH. A reverse-phase LC separation was performed on Luna C8 column with the mixture of acetonitrile-ammonium formate (10 mM, pH 4.5) (67:33, v/v) as mobile phase. The detection of analytes was performed using an electrospray ionization tandem mass spectrometry in the multiple-reaction-monitoring mode. (omitted)

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.459-461
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• 1990

Me performed an experiment about preionization electron number density of charge transfer type KrF excimer laser. At the total pressure of 1.8 and 2.2 atm with helium (He) buffer gas, the experimental range of the electron number density is 8-9 ${\times}$ 10 cm The distance between electrode and preionization pin is 15 mJ at charging voltage of 27kV,gas pressure of 2.2 atm,gas mixture of F /Kr/He = 0.3/396.7(%).

• Archives of Pharmacal Research
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• v.17 no.4
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• pp.263-268
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• 1994

This study was conducted to characterize the in vivo pharmacology of KR-30988, KR-30992 and losartan, new AT antagonists, given as i.v. cumulative doses, in two antimal models of high renin, conscious renal artery-ligated hypertensinve rats (RHRs) and nomotensive rats anesthetized with urethane (90 mg/kg, i.p.) and .alpha.-chloralose (90 mg/kg, i.p.), with a special emphasis on the phamacological characterization of the latter model. In conscious RHRs, KR-30988, KR-30992, losartan and captopril caused a dose-dependent decrease in blood pressure, their relative potencise ($ED_{20}$) being 0.057, 0.028, 0164 and 0.018 mg/kg, i.v., repectively. In anesthetized rats, 2 hours after anesthesia, plasma renin activity was increased from 7.31 tp 34.07 ng/ml/h, the level approximately 1.5 times greater than the highest level in RHRs. In anesthtized rats, the $ED_{20}$s for all four compounds were 0.004 mg/kg i.v., respectively. By comparison, $ED_{20}$sfrom anesthetized rats were 4 to 5 times smaller than those from conscious RHRs, with a good correlation (.gamma. = 0.999) noted between thetized rats to the hypotensive activity of the compounds and the same order of potencies intwo models. These results suggest that, in addition to PHRs, the normotensive rats anesthetized as above can serve as a suitable model for the rapid phamacological evaluation of $AT_1$ receptor antagonists.

• Journal of the Korean Vacuum Society
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• v.11 no.2
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• pp.127-134
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• 2002

Recently, Plasma display panel(PDP) has been in the spotlight as one of the next generation flat-panel-display device. The luminance and luminous efficiency improvement is the hot issues for making a plasma display into a large flat panel device. In this paper, We suggest a new penning gas mixture, in order to find the optimum mixture gas in plasma display panel. The optimum gas composition has been found by the partial pressure of inert gases(such as Af and Kr added to matrix of He(70%)-Ne(27%)Xe(3%) and Ne(96%)-Xe(4%)). The influences of Ar or Kr addition to Ne(96%)-Xe(4%) and He(70%)-Ne(27%)-Xe(3%) mixture gases are experimentally investigated for AC Plasma Display Panel. When rare As(0.01%-0.03%) or Kr(0.01%-0.03%) is added Ne-Xe and He-Ne-Xe mixture gases, the luminance increases over 10%-20% and luminous efficiency increases over 10%-20% at 200 Torr. It is sure that luminance and efficiency are improved by Penning effect. Also, This influence of Penning effect is shown by increased wall charge(10%-25%). In addition to the result, firing voltage and minimum sustain voltage was approximately decreased by 2V-3V.

• Journal of the Korean Vacuum Society
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• v.15 no.1
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• pp.73-80
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• 2006

Thermally-driven effusion of inert gases out from Si(100), into which energetic $\~l keV\;He^+,\;Ne^+,\;A^r+,\;and\;Kr^+ ions$ had been implanted at a moderate substrate temperatures of $\~400 K$, was investigated by means of temperature-programmed desorption (TPD) mass spectrometry. While He effused out broadly over $500\~1,100 K$, Ne, Ar, and Kr effusion occurred sharply at 810, 860, and 875 K, respectively. Hydrogen adsorption/desorption analysis for the ion-treated Si(100) surfaces indicated minimal to severe damage by ions with increasing mass from He to Kr. Implications of these results in light of literature reports are discussed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.11
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• pp.3473-3479
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• 2009

The pharmacological profile of KR-31081, a newly synthesized AT1 receptor antagonist, was evaluated in pithed rats, conscious renal hypertensive rats (RHRs) and conscious furosemide-treated beagle dogs. In pithed rats, KR-31081 (i.v.) induced a non-parallel right shift in the dose-pressor response curve to angiotensin II (ID50: 0.05 mg/kg) with a dose-dependent reduction in the maximum responses; this antagonistic effect was about 40 times more potent than losartan (ID50: 1.74 mg/kg) which showed competitive antagonism. KR-31081 did not alter the responses induced by other agonists such as norepinephrine and vasopressin. In RHRs, orally given KR-31081 produced a dose-dependent and long-lasting (>24 h) antihypertensive effect with a higher potency to losartan (ED20: 0.30 and 3.36 mg/kg, respectively). In furosemide-treated dogs, orally given KR-31081 produced a dose-dependent and long-lasting (>8h) antihypertensive effect with a rapid onset of action (time to Emax: 1-1.5 h) and 20-fold greater potency than losartan (ED20: 0.41 and 8.13 mg/kg, respectively). These results suggest that KR-31081 is a potent, orally active AT1 receptor antagonist useful for the research and diagnostic tools as an added exploratory potential.

• Journal of the Korean Chemical Society
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• v.21 no.6
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• pp.395-403
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• 1977

Significant structure theory was applied to some liquid mixture systems ranging from simple monatomic molecule systems to polyatomic molecule systems, and the activity coefficients ${\gamma}$ of the liquid mixture systems were calculated over whole mole fractions using the following thermodynamic relation $RTln_{{\gamma}i} = (\frac{{\partial A}^E}{{\partial N}_i})_{T,V,N_i} $ where $A^E$ represents the excess Helmholtz free energy, and $N_i$ is the number of molecules of component i. The activity coefficients of the solutions such as monatomic molecule systems (Ar-Kr, Kr-Xe) and diatomic molecule systems $(Ar-O_2,\;N_2-CO)$ and $CH_4-Kr$ systems whose components have similar shapes for intermolecular potential curves were calculated successfully only with the ${\delta}E_s$, correction parameter for energy $E_s$, for mixture systems. For other systems such as $Ar-N_2,\;O_2-N_2\;and\;CH_4-C_3H_8$ whose components have dissimilar intermolecular potential curve shapes an additional correction parameters ${\delta}$V and even one more parameter ${\delta}$n were necessary [see Eqs.(10)∼(12)].