• Journal of the Korean Chemical Society
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• v.63 no.1
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• pp.37-44
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• 2019

N,N'-bis(ethyldihydrogen phosphate)-1,4,5,8-naphthalene bis(dicarboximide) (EPNI) and N,N'-bis(ethyldihydrogen phosphate)-3,4,9,10-perylene bis(dicarboximide) (EPPI) and their zirconium bisphosphate multilayers (Zr-EPNI and Zr-EPPI), that had been briefly reported by us, were further investigated in terms of their electrochemical properties. EPNI in aqueous solution showed typical two reversible reductions at ITO electrode but the reductions were strongly dependent on solution pH while EPPI showed only an irreversible reduction. The single and mixed multilayers of Zr-EPNI and Zr-EPPI were well constructed on ITO electrode by the alternate adsorptions of zirconium ion and the bisimides. While Zr-EPNI multilayer on ITO electrode showed single broad reversible reduction with $E_{1/2}=-0.68V$, Zr-EPPI gave two separated reductions at $E_{1/2}=-0.54$ and -0.81 V vs SCE, quite differently from the solution properties. The average layer densities of the multilayers were estimated as $1.5{\times}10^{-10}$ and $2.3{\times}10^{-10}mol/cm^2$ for Zr-EPNI and Zr-EPPI, respectively. Both the monolayers of Zr-EPNI and Zr-EPPI could not completely block the electron transfer between $Fe(CN){_6}^{3-}$ in solution and ITO electrode but 3-5 layers of Zr-EPNI and Zr-EPPI could block it completely and mediated the one-way electron transfer at the potential shifted to their reduction potentials. When the monolayer of zirconium 1,10-decanediylbisphosphonate (Zr-DBP) was used as a sublayer of Zr-EPNI and Zr-EPPI layers, the mediated electron transfer became prominent without any direct electron transfer.

• Membrane Journal
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• v.4 no.4
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• pp.221-231
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• 1994

The GR51PP(MWCO 50,000) and GR40PP(MWCO 100,000) membranes manufactured by DDS were used in ultrafiltration of dextran(Mw. : 500,000) solution in flat plate ultrafiltration cell filled with various types of turbulence promoters. The flux improvement by using turbulence promoter was higher in laminar flow region than in turbulent flow region. The maximum improvements of permeate flux were foud as 112% and 50% I laminar flow region and turbulent flow region, respectively. Also, the solute rejection of the ultrafiltration membrane was improved by turbulence promoters and its effect was significant in the high transmembrane pressure and laminar flow region. The smaller the spacer mesh size was used, the higher the flux improved, but the pressure drop in ultrafiltration cell also increased. In laminar flow region, pressure drop by the spacer was negligible, but in turbulent flow region it changed significantly depending upon the mesh size of the spacer and therefore, its mesh size must be baken into account in the design of the process. The predicted results of the modified mass transfer correlation had better agreement with experimental results than those of unmodified one, The modified mass transfer correlations for laminar and turbulent flow region are shown as follow. $N_{sh}=0.151(N_{Re})^{0.199}(N_{Sc})^{0.22}(N_{Scm})^{0.197}\;(625 $N_{sh}=0.0165(N_{Re})^{0.428}(N_{Sc})^{0.33}(N_{Scm})^{0.223}\;(5015

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.73-73
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• 2003

• Proceedings of the Materials Research Society of Korea Conference
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• 1999.11a
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• pp.190-190
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• 1999

• Proceedings of the Materials Research Society of Korea Conference
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• 1999.11a
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• pp.189-189
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• 1999

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3437-3440
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• 2012

• Bulletin of the Korean Chemical Society
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• v.26 no.10
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• pp.1600-1602
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• 2005

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4361-4365
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• 2011

The nucleophilic substitution reactions of bis(N,N-dimethylamino) phosphinic chloride (3) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are investigated kinetically in acetonitrile at $65.0^{\circ}C$. The anilinolysis rate of 3 is rather slow to be rationalized by the conventional stereoelectronic effects. The magnitudes of ${\rho}_X$ (= -6.42) and ${\beta}_X$ (= 2.27) values are exceptionally great. The deuterium kinetic isotope effects (DKIEs; $k_H/k_D$) are secondary inverse ($k_H/k_D$ = 0.69-0.96). A concerted $S_N2$ mechanism involving a backside attack is proposed on the basis of secondary inverse DKIEs and the variation trend of the $k_H/k_D$ values with X. The anilinolyses of six phosphinic chlorides in MeCN are briefly reviewed by means of DKIEs, steric effects of the two ligands, positive charge of the reaction center phosphorus atom, and selectivity parameters to obtain systematic information on phosphoryl transfer reaction mechanism.

• The Journal of Pediatrics of Korean Medicine
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• v.17 no.2
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• pp.37-53
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• 2003

Objective : To find risk factor and symptoms for transferred newborn from postpartum care center Method : We performed a follow-up study using medical record. Subjects comprised 188 neonates(include 4 twins) and 184 women in childbed who were hospitalized in oriental postpartum care center from January, 1, 2002 to December, 31, 2002. Result: Transferred newborn was total 24, N.V.D. 17, C.S. 7, male and female were 12 separately. The symptom of transfer was fever(16), diarrhea(4), jaundice(3), convulsion(1) Transferred number and rate was male 12(10.7%), female 12(15.8%). In delivery method, total normal vaginal delivery(N.V.D.) was 136 and transferred 17(12.5%), total cesarean section(C.S.) was 52 and transferred 7(13.5%). Transferred rank was N.V.D. female(17.9%). C.S. male(15.6%), C.S. female(10%), N.V.D.(8.6%). Of the 188 neonates. immature infants were 2 and transferred 1(50%), term infants were 184, transferred 23(12.5%), post-term infants were 2 and transferred none(0%). In age of women in childbed, transferred ratio was 15.4%(over 35), 15.2%(25-29), 10.5%(30-34). In fever,. C.S. infants were more transferred than N.V.D. and male infant had a tendency to transfer in later period of hospitalization and female in early period. It seems that transfer was related to abortion. In diarrhea, all was N.V.D. and their diagnosis was rotavirus. The average age of women in childbed was yonger(28.5). In jaundice, all was 1st, and average birth weight was lighter(3153g). The average age of women in childbed was older(30). In convulsion, birth weight was lighter(3153g), and age of women in childbed was older(30). Conclusion : There's any relation with sex and delivery method, birth weight and mother's age in transfer. But we cannot find any statistically significance. Further prospective studies are needed to find risk factors in transfer.

• Nuclear Engineering and Technology
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• v.49 no.7
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• pp.1457-1462
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• 2017

Unsteady thermal processes in storage containers with spent nuclear fuel were modeled. The daily fluctuations of outer ambient temperatures were taken into account. The modeling approach, which is based on the solving of conjugate and inverse heat transfer problems, was verified by comparison of measured and calculated temperatures in outer channels. The time delays in the reaching of maximal temperatures for each spent fuel assembly were calculated. Results of numerical investigations show that daily fluctuation of outer temperatures does not have a large influence on the maximal temperatures of stored spent fuel, so that fluctuation can be neglected and only daily average temperature should be considered for safety estimation using the "best estimation" approach.