• Fire Science and Engineering
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• v.29 no.5
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• pp.7-13
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• 2015

This study was performed to test the production of combustion toxic gases by Pinus rigida specimens treated with various types of methylpiperazinomethyl-bis-phosphonic acid $M^{n+}$ ($PIPEABPM^{n+}$) and methylpiperazinomethyl-bis-phosphonic acid (PIPEABP). Three coats of 15 wt% $PIPEABPM^{n+}$ and PIPEABP solutions were applied to plates of Pinus rigida at room temperature. After drying the treated specimens, the production of combustion toxic gases was examined using a cone calorimeter (ISO 5660-1). The specimens treated with $PIPEABPM^{n+}$ showed lower carbon monoxide production ($CO_{2\;peak}$; 0.0136~0.0178% at 532~678 s) than the PIPEABP plates, except for the specimen treated with $PIPEABPFe^{3+}$. In addition, the peak carbon dioxide production ($CO_{2\;peak}$) was lower (0.03648~0.3648% at 373~433 s) than that of the PIPEABP-treated plate. Notably, oxygen production was much higher than 15%, which can be fatal to humans. Therefore, the resulting risk could be eliminated. The results indicate that the combustion toxicities were partially decreased due to treatment of the virgin plate with $PIPEABPM^{n+}$.

• Journal of Korean Society of Forest Science
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• v.89 no.1
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• pp.116-125
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• 2000

This study was conducted to investigate the effects of CEPA(2-chloroethyl phosphonic acid) on bark physiology and anatomy of lactree(Rhus verniciflua Stokes). Sample trees of similar size and growth rate were selected from 7-year-old lactree plantation located in Hyengsung-kun, Kangwon-do. Lanolin pastes containing 0.1, 1, or 10% CEPA were put into the bark-removed hole made by corer(${\phi}1cm$) on the main stem at 1.2m above the ground on June 16, 1995. Five weeks after application of CEPA, bark thickness was markedly increased as a result of the increase in the amount of phloem and intercellular spaces, and correlated with the increased production of urushiol. By the application of 10% CEPA, bark thickness was increased approximately 2.5 times, and the urushiol content within bark was increased 2.8 times compared to that of untreated trees because CEPA stimulated the accumulation of urushiol within bark. Treatment of 10% CEPA also increased the size and the total number of secretory canals, and induced an increase in ray width. The phloem parenchyma cells of CEPA-treated trees were well-developed and closely packed with little intercellular space.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.184-184
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• 2006

We have succeeded in the preparation of high molecular weight polybenzimidazoles by solution polycondensation of 3,3'-diaminobenzidine tetrahydrochloride with isophthalic acid, terephthalic acid, or with their derivatives using polyphosphoric acid both as solvent and as condensing agent. Also, we modified phosphoric acid into fluoroalkyl-phosphonic acids[F-PA]. The main reasons are as follows, first of all F-PAs are stronger acids than PA and alkylphosphonic acids which should promote proton hopping and transport. In addition, F-PA has weaker adsorption onto Pt which help to prevent electrocatalyst poisoning and promote higher oxygen reduction activity. The ionic conductivity of 85%-H3PO4 doped membranes show $10^{-2}\;Scm^{-1}\;to\;3{\times}10^{-2}\;Scm^{-1}\;at\;150^{\circ}C$ MEA with 2 %-added electrolyte shows slightly higher cell voltage than the others.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.74-77
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• 2012

A new catalytic system has been developed in the synthesis of bis(indolyl)methanes using cyclic phosphonic acid anhydride(T3P). Short reaction time, simplicity of isolation, safe catalyst and high yields of product are the features.

• 대한핵의학회:학술대회논문집
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• 2000.05a
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• pp.72.2-72.2
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• 2000

• Bulletin of the Korean Chemical Society
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• v.16 no.9
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• pp.886-891
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• 1995

Electroactive monolayers based on zirconium(Ⅳ) phosphonate film were prepared on gold and tin oxide electrodes by sequential layer-by-layer depostion technique. High transfer coefficient values and surface coverages of surface bound redox molecules were obtained from the electrochemical measurements of heterogeneous electron transfer rates for monolayer modified electrodes. 1,10-Decanediylbis(phosphonic acid) (DBPA) monolayer as insulating barrier was effective in blocking electron transfer. However, these film modified oxide electrode shows voltammetric behavior of diffusion/permeation process taking place at very small exposed area of modified electrode through channels due to structural defects within film when a very fast redox couple such as Ru(NH3)63+ is hired.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05b
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• pp.61-64
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• 2004

The proton transport through proton exchange membranes is controlled by the distribution of hydrated structure connected with negative-charged fixed ions such as phosphonic acid, carboxylic acid and sulfonic acid, or water molecules within the membrane.(omitted)

• Analytical Science and Technology
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• v.12 no.5
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• pp.370-374
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• 1999

Extraction chromatography was used to scarch optimum separation conditions of terbium. Stationary phase was 2-ethylhexyl-2-ethylhexyl phosphonic acid(HEH[EHP])levextrel (-100~+150 mesh), column size was ${\Phi}20{\times}530mm$ and kept constantly temperature at $50^{\circ}C$, adsorption flow rate of $0.2mL/cm^2{\cdot}min$, elution flow rate of $1.0mL/cm^2{\cdot}min$, column diameter to packing height of 1:15. But to search optimum separation conditions of terbium, it changed the eluent acidity, the loading weight of sample. the composition of sample. In conclusion, acidity was 0.6 N HCl, loading weight of sample was about 5% and composition of sample was $Gd_2O_3(20%)+Tb_4O_7(60%)+Dy_2O_3(20%)$. Moreover purity of separated terbium by ICP-AES analysis was 99.98% in yield of 99.99%.

• Applied Chemistry for Engineering
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• v.26 no.6
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• pp.631-639
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• 2015

Extraction/separation of cobalt by solvent extraction is reviewed. Separation of cobalt using various reagents and also cobalt recovery from scrap using commercial extractant were analyzed. The separation ability for cobalt followed the order of phosphinic > phosphonic > phosphoric acid due to the increasing stabilization of tetrahedral coordination of cobalt complexes with the extractant in the organic phase. Depending upon the solution composition, commercial extractants like Cyanex 272, D2EPHA and PC 88A should primarily be used for commercial extraction processes and also the efficient management of their combination could address various separation issues associated with cobalt bearing scrap.

• Journal of the Korean Institute of Landscape Architecture
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• v.15 no.3
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• pp.11-19
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• 1988

The purpose of this study is to investigate ways to control the wind dispersal of contton-wrapped seeds of such poplars and willows as Poplus alba, P. tomentiglandulosa, P. euramericana, P. deltoides, and Salix pseudo-lasiogyne. These trees are hated by many people because of their seeds blowing all over the place during May. These cottony seeds can be nuisance to various types of outdoor activities, pose safely threat to drivers, become fire hazards during prolonged spring dry spells, and cause many types of health hazards of allergy such as sneezing. rhinitis, asthma, and skin rashes. Four control methods can be used to resolve the problem. First, pruning can be a solution, but it is unsatisfactory in terms of costs and outcome. Second, planting of male trees only can be a solution, but it is hard to identify sexes of saplings. Third, female trees can he replaced with other species. But it requires high costs and takes at least ten years to functionally replace the removed ones. As an alternative to such unsatisfactory control methods, the possibility of applying plant growth regulators has been investigated since 1983. During the pre-test, various concentrations and mixtures of them were either sprayed or injected, but failed to achieve any promising results. But the injection of a mixture made up of 0.75g of 2-chloroethane phosphonic acid with 0.2 mg of GA in 300cc water in the end of March produced premature falling of almost all aments and capsules of treated poplars and willows. It was found that the effect of the injection lasts two years. The results of the main experiment of 1987 can be summarized as follows ; First, the injection of the mixture of 2-chloroethane phosphonic acid and GA increases the premature abscisin of aments and capsules, thus reducing the wind dispersal of the cottony seeds of S. pseudolasiogyne, P. tomentiglandulosa, and P. euramericana 1644.09, 1200.61, and 1485.11 times, respectively, than that of the naural abscisin, It is estimated that the average number of wind-blown seeds reduced are approximatively 6,185,100, 4062,900, and 2,830,670 per tree, respectively. Second, the treatment causes no observable side effects on the growth of the samples tested.