• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.11
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• pp.1637-1643
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• 1989

In this study, phosphosilicate glass(PSG) film was deposited by the oxidation of phosphine (PH3) and silane(SiH4) in nitrogen ambient with a conventional conveyerized Atmospheric Pressure Chemical Vapor Deposition(APCVD)system and phosphorus concentration is measured by using FT-IR technique. The flow characteirstics and etch rate variations ofthe films, depending on phosphorus concentrations, are investigated. Special emphasis is focused on the yield variations of NMOS-based 256K DRAM with 1.2\ulcorner metallization spacing with increasing phosphorus concentrations. As a result, the data indicates that the fairly good yield can be obtained within the range of between 8 and 10wt% phosphorus concentration, which result in a slope of flow within 45\ulcorner10\ulcorner The analysi of failure mechanism is also accompanied.

• Journal of the Korean Chemical Society
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• v.7 no.4
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• pp.271-276
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• 1963

The distribution ratio of lanthanon nitrates in the TBPO- and TOPO-toluene systems were studied radiometrically as a function of solvent, nitrate and atomic number(Z). The plots of log Kd vs. Z shows two straight lines which are crossing at Z = 63∼64. The solvent dependency was same for lighter and heavier lanthanons but nitrate dependency was different between the two parts.

• Journal of the Korean Applied Science and Technology
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• v.25 no.3
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• pp.291-298
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• 2008

Although the pyrimidine derivatives were obtained in low yields ranging from 8% to 20%, we reported the successful preparation of N,N-diaryl-pyrimidin-2-amine derivatives starting from the corresponding 2-aminopyrimidines (1a-1c), by direct palladium-catalyzed arylation using different arylbromides. The reasons of low yields are thought to be the electronic and steric effects by the neighboring aromatic systems. The absorption spectra and photoluminescent spectra of compounds (3a 3g and 4a-4c) were measured using dichloromethane on the concentration of 25 mM by UV vis spectroscopy and luminescent spectroscopy. Pyrimidine derivatives 4a, 4b, and 4c showed moderate emission maxima at 474 nm, 481 nm, and 367 nm, respectively, while other compounds showed very weak photoluminescence or no photoluminescence at all.

• Applied Biological Chemistry
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• v.32 no.3
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• pp.265-269
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• 1989

Effects of air-tighteness of packing material and aluminum phosphide fumigation on mortality of rice weevil were studied during rice storage. Air-tight storage of rice in sealed bag of 0.1mm PE film or sealed glass bottle reduced the deterioration of rice quality and killed all rice weevils after 60 days storage, while paper bag, PP bag and straw bag storage kept them alive. One tablet of aluminum phosphide in one cubic meter heap of rice packed in PP bag was sufficient to kill all rice weevil in it, when the heap was covered by 0.15 mm PE film during fumigation.

• Bulletin of the Korean Chemical Society
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• v.19 no.9
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• pp.957-961
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• 1998

Intramolecular Diels-Alder cycloadditions of 2-pyrone-3-carboxylates with trans-vinyl silaketal groups tethered via a chiral, non-racemic 1,3-butanediol auxiliary proceeded in unexpected stepwise cycloadditions through ionic intermediates to provide cis-disubstituted bicylolactones. The ratio of two isomers, exo and endo, was 5 to 1, and each isomer was found to be diastereomerically pure (>99% de). Their relative and absolute stereochemistries were determined by $^1H$ NMR spectroscopy and confirmed by X-ray crystallography of minor, endo-adduct 9. The major exo-adduct was successfully transformed to (-)-2-butyl substituted A-ring phophine oxide 16, a key element for the synthesis of 2-butyl vitamin D3.

• Bulletin of the Korean Chemical Society
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• v.16 no.3
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• pp.211-214
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• 1995

The catalytic activities of palladium(0,Ⅰ,Ⅱ)-diphosphine complexes were investigated in styrene oxidation using H2O2 as terminal oxidant. The rates showed a dependence on the chelate ring patterns of complexes (PdCl2L); 5-membered ring (L=dppe: 1,2-bis(diphenylphosphino)ethane) < 6-membered ring (L=dppp: 1,3-bis(diphenylphosphino)propane) < 4-membered ring (L= dppm: bis(diphenylphosphino)methane). This sequence correlates with the ligand field strength and interactions between metal and phosphine ligands. Pd(Ⅱ,Ⅰ)-diphosphine complexes which are capable of making 4-membered chelate ring showed an enhancement of catalytic activities for styrene oxidation. The catalytic activities of Pd(0,Ⅰ,Ⅱ)-diphosphine complexes are described in terms of electronic and steric factors.

• Bulletin of the Korean Chemical Society
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• v.18 no.2
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• pp.218-221
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• 1997

When phenylation of styrene was carried out in the presence of Pd(OAc)2 and PPh3 in benzene, trans-stilbene was obtained in good yield (566%) with high selectivity (98%) under mild condition (55 ℃, 50 psi O2, 20 h). Since trans-stilbene could be produced not only from benzene but also from phenyl group of PPh3 by migration of its phenyl group to Pd, the competitiveness of benzene and the migratory aptitude of aryl group of triarylphosphine toward styrene has been investigated with various phosphines (PR3: P(p-C6H4CH3)3, P(p-C6H4OCH3)3, P(p-C6H4F)3, P(p-C6H4Cl)3, P(C6H5)3, P(C6H11)3, P(OC4H9n)3, P(CH2C6H5)3 and P(C6F5)3). The yield and selectivity toward trans-stilbene are increased as the basicity of the phosphines increases. The composition of arylated olefin from arylphosphine, in turn, increases as the electronegativity of the substituent on the aryl group of arylphosphines increases.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.3
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• pp.347-357
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• 2018

The applicability of room temperature ionic liquids (RTILs), 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([$C_nmim$] [$Tf_2N$]), was investigated for the extraction of Am(III) and Eu(III) from nitric acid using n-octyl(phenyl)-N,N-diisobutyl carbamoylmethyl phosphine oxide (CMPO) and tri-n-butylphosphate (TBP) as extractants. The distribution ratios of Am(III) and Eu(III) in CMPO-TBP/[$C_nmim$][$Tf_2N$] were measured as a function of various parameters such as the concentrations of nitric acid, CMPO, and TBP. The results were compared with those obtained in CMPO-TBP/n-dodecane (n-DD). With comparable concentrations of the extractants, the distribution ratios obtained with RTILs were much higher than those obtained with n-DD. It was observed that the extraction efficiency was less for Eu(III) than for Am(III). The extraction of Am(III) and Eu(III) decreased with increases in the feed acidity for all three RTILs. The results suggest that the extraction of Am(III) and Eu(III) by CMPO in RTILs from nitric acid proceeds through the cation-exchange mechanism. The distribution ratios of Am(III) and Eu(III) increased with increases in the concentration of CMPO for all three RTILs. A linear regression analysis of the extraction data resulted in a straight line with a slope of about 3, suggesting the involvement of 3 molecules of CMPO during the extraction process.

• Polymer(Korea)
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• v.30 no.3
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• pp.266-270
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• 2006

Poly [(dimethylmethylyinyl) siloxane] phosphineoxide (PMViSPO) was prepared by adding phosphorus oxychloride $(POCl_3)$ to poly (dimethylmethylyinyl) siloxane (PMViS) at $0^{\circ}C$ under nitrogen atmosphere. Cadmium selenide (CdSe) was prepared by reacting cadmium oxide (CdO), tetradecyl-phosphonic acid (TDPA), trioctylphosphine oxide (TOPO) at $300^{\circ}C$, and adding solution of dissolved Se to tributylphosphine (TBP) and trioctylphosphine (TOP) CdSe-poly [(dimethylmethylvinyl) siloxane] phosphine-oxide (CdSe-SPO) adduct was synthesised by adding PMViSPO to CdSe solution. Liquid silicone rubber composite (LSRC-1) was prepared by compounding $\alpha,\omega-vinyl$ poly (dimethylsiloxane) (VPMS), $\alpha,\omega-hydrogen$) poly(dimethylsiloxane) (HPMS), and CdSe under Pt catalyst, and also LSRC-2 was prepared from VPMS, HPMS, and CdSe-SPO using Pt catalyst. It was confirmed that CdSe nanoparticles with photoluminescence characteristics was dispersed uniformly in LSR matrix. The diameter of CdSe was $30\sim50nm$. By measuring the number of CdSe nanoparticles, 202 particles of CdSe in LSRC-2 and 165 particles of CdSe in LSRC-1 were dispersed in the same area of LSR matrix. Thermal stability for LSRC-2 compounded with CdSe-SPO was better than LSRC-1.

• Food Science and Preservation
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• v.13 no.6
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• pp.708-713
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• 2006

In order to study the quarantine and sanitization methods for dried red pepper, comparative effects of commercial fumigation (methyl bromide/MeBr, phosphine gas/$PH_3$) and gamma irradiation (5, 10 kGy) were investigated in terms of soluble pigment capsanthin, and capsaicin content of pepper during storage at mom temperature for 8 months. In water-soluble pigment, the degree of browning was highest in the fumigated samples, particularly in pericarp part, as compared to the control and irradiated samples. In general, the changes in capsanthin content were not apparent by treatment groups, but some reduced content were found in 10 kGy-irradiated pericarp group, Eight months of storage resulted in the significant decrease in capsanthin contents of pericarp part by $26.76{\sim}38.08%$ depending on treatment groups. The contents of capsaicin and dihydrocapsaicin were not different between the control and 5 kGy groups, while their contents decreased in both fumigated and 10 kGy-irradiated groups(p<0.05). The reduction in pungent component was observed in all the sooted samples, which was mote apparent in teated groups than in the control.