• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.04a
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• pp.190-191
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• 2008

In the presence of heat and oxygen, phosphorous compounds decompose to form water vapor and phosphorous oxides. The phosphorous oxides subsequently reat with the polymer matrix and dehydrate it, reforming phosphoric acids. These acids again decompose to reform water vapor and phosphorous oxides. Ultimately as the water available from normal combustion of hydrocarbons diminishes, the phosphorous oxide reat with hydrocarbon fragments to produce a very high melting point char at the interface between the polymer and the heat material. The chars, which contain phosphorous, rapidly dissipate heat energy and lose their glow. This antiglow property of phosphorous compound contributes to its availability as a flame retardant. In this study, the acrylated phosphorous compounds will be prepared and demonstrated as flame retardants.

• Journal of the Korean Applied Science and Technology
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• v.24 no.2
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• pp.124-139
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• 2007

In order to obtain the maximum flame retardancy with the minimal deterioration of physical properties of PU flame-retardant coatings, chlorine and phosphorous functional groups were introduced into the pre-polymer of modified polyesters. In the first step, the tetramethylene bis(orthophosphate) (TBOP) and neohexanediol dichloroacetate (DCA-adduct) intermediates were synthesized. In the second step, 1,4-butanediol and adipic acid monomers were polymerized with the two kind of intermediates to obtain copolymer. The modified polyesters containing chlorine and phosphorous (ATBA-10C, -20C, and -30C) were synthesized by adjusting the contents of chlorine compound (dichloroacetic acid, 10, 20, 30 wt%) with fixed the content of phosphorous compound (2 wt%). The PU flame-retardant coatings (TTBAH -10C, -20C, and -30C) were prepared using the synthesized ATBAs and HDI-trimer as curing agent at room temperature. The physical properties of PU flame-retardant coatings with chlorine and phosphorous were inferior to those with phosphorous only and the properties were getting worse with increasing chlorine content. Flame retardancy was tested with three methods. With the vertical method, Complete combustion time of ATBAHs were $259^{\sim}347$ seconds, which means that the prepared coatings are good flame-retardant. With the $45^{\circ}$ Meckel burner method, char lengths of the three prepared coatings were less than 2.9 cm, which indicates that the prepared coatings are 1st grade flame retardancy. With the limiting oxygen index (LOI) method, the LOI values of the three prepared coatings were in the range of $30^{\sim}35%$, which proves good flame retardancy of the prepared coatings. From the results of flame retardancy tests of the specimens that contain the same amounts of flame retarding compounds, it was found that the coatings containing both phosphorous and chlorine show higher flame retardancy than the coatings containing phosphorous alone. This indicates that some synergy effect of flame retardancy exists between phosphorous and chlorine.

• Journal of Korean Society on Water Environment
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• v.22 no.1
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• pp.30-36
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• 2006

This study was carried out to evaluate the performance of Modified Ludzsck Etinger (MLE) process with waste oyster shell media in aerobic tank. Influent flow was 36 L/d and the order of reactor was anoxic, aerobic and sedimentation tank and unit hydraulic retention time was 2 hr, 6 hr and 4 hr, respectively. Sludge recycling rate in sedimentation tank and internal recycling rate were 100%. Media fill rate in aerobic tank was 5%, 10% and 17% and fluid MLSS concentration in aerobic tank was 3000~4000 mg/L. Average TCOD removal rate was 91~93%, TBOD 92~96%, SS 95~96% and when media fill rate was 10% or more, in organic compound removal it could satisfy with wastewater discharge standard. Average total nitrogen removal rate was 70~76% and average total phosphorous removal rate was 58~65%. With media fill rate increasing, total phosphorous average removal rate also increased. For it was that released calcium ion from waste oyster shell reacted with soluble phosphorous. From these experiment results, the MLE process using waste oyster shell as media is a practical method for advanced sewage treatment in rural area.

• Journal of Environmental Health Sciences
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• v.36 no.6
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• pp.502-509
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• 2010

In this study, the (phosphorous removal) the characteristics of phosphorous removal due to (the iron compound precipitated) iron compound precipitation by iron electrolysis in (the anoxic. oxic process) anoxic and oxic processes (equipped with the) in an iron precipitation device were analyzed. During the device operation period, the average concentration of BOD, T-N, and T-P were 219.9 mg/l, 54.6 mg/l and 6.71 mg/l, respectively. The BOD/$COD_{Cr}$ ratio was 0.74, and the BOD/T-N and BOD/T-P ratios were 4.0 and 32.8, respectively. The removal rate of (the organic matters) organic matter (BOD and $COD_{Cr}$) was very high at 91.6% or higher, and that of nitrogen was 80.5%. The phosphorous concentration (of the final) in the treated water was 0.43 mg/l (0.05-0.74 mg/l) on average, and the removal efficiency was high at 90.8%. The soluble T-P concentrations in (an) the anoxic reactor, oxic reactor (II) and final treated water were 1.99 mg/l, 0.79 mg/l and 0.43 mg/l, respectively, which indicated that the phosphorous concentration in the treated water was very low. Regardless of the changes in the concentrations of (organic matters) organic matter, nitrogen and phosphorous in the influent, the quality of the treated water was relatively stable and high. The removal rate of T-P somewhat increased with the increase in the F/M ratio in the influent, and it also linearly increased in proportion to the T-P loading rate in the influent. In the treatment process used in this study, phosphorous was removed (using) by the precipitated iron oxide. Therefore, the consumption of organic (matters) matter for biological phosphorus removal was minimized and (most of the organic matters were) was mostly used as the organic carbon source for the denitrification in the anoxic reactor. This (can be an economic) treatment process (without the need for the supply of additional organic matters) is economic and does not require the supply of additional organic matter.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.4047-4054
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• 2010

We studied the release characteristics of the marine sediment which could facilitate sea eutrophication through some lab-scale simulation experiments. Environmental indicators such as pH, ORP(oxidation reduction potential), nitrogens, and phosphates were measured in order to calculate the corresponding release rates. $CaO_2$, an oxygen releasing compound was used to determine how it would effect on the natural process of sedimental release. COD, ammonia nitrogen, phosphorous compounds were less released under the oxic environment caused by $CaO_2$. This basic data will help developing methodology for reducing marine eutrophication which may be initiated by the sedimental release.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.13
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• pp.119-126
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• 1973

In order to investigate the effects of phosphorous fertilizer such as fused Phosphate, compound fertilizer and triple phosphate on barley(growth and yield at the fixed level of nitrogen and potassium, 4 level of hosphorous) has been tested at Suwon. Iri. Kwangju ani Daegu with randomized completeblock design. The results obtained could be summarized as follows. 1. In four locations. increased application of phosphorus have brought earlier maturity in barley regardless the type of fertilizer but fused phosphate considered to have more effects on stimulation of maturity of barley compare with the others. 3. Fused phosphate increased yield higher by-8kg/10a application compare with the same level of compound fertilizer and triple phosphate but there was no differences in yield at 12kg/10a phosphate but there was no differences in yield at 12kg/l0a application among the fertilizers except Kwangju and Suwon. 3. Grain weight was considerably higher in application of fused phosphate Thus are considered effects phosphate. 4. Optimum amount of phosphorous fertilizer was considered 8kg/l0a. Application of 4kg per 10a produced lower yield than 8kg and slightly or no increased yield was observed in 12kg application. 5. Among the 4kg/10a applied condition of phosphorous fertilizers, yield was decreased at fused phosphate treatment compare with the others and this fact resulted supposedly due to the lower portion of valid phosphorus in fused phosphate because of its citric acid solubility. At level of 12kg/10a application fused phosphate was considered more effective in yield increment.

• Clean Technology
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• v.23 no.4
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• pp.378-387
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• 2017

To obtain epoxy resin with permanently attached flame-retardant groups, phosphorus compound containing di-hydroxyl group [10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phospha phenanthrene-10-oxide, DOPO-HQ] and silicone compound containing di-hydroxyl group (polydimethylsiloxane, hydroxyl terminated, PDMS) were reacted with uncured epoxy prepolymer (diglycidyl ether of bisphenol A, DGEBA) and then cured using 4,4-diaminodiphenylmethane (DDM) as a crosslinking agent. The properties of the resulting epoxy materials were characterized using Fourier transform infrared (FTIR) spectrometer, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), limiting oxygen index (LOI) test/vertical burning test (UL 94-V test), tensile properties test and impact test. This study examined the effect of phosphorus/silicone compound contents on the thermal/mechanical properties and flame retardancy of cured epoxy resins containing phosphorus and silicone compounds. It was found that the thermal/mechanical properties of epoxy resins containing phosphorus and silicone components were higher than those of simple epoxy resin. The flame-retardancy (LOI: 29.9 ~ 31.8% and UL 94-V: V-0) of all samples containing phosphorus compound and phosphrous compound/silicone compound was found to be passed the flame-retardant requirements (LOI: > 30%, UL 94-V: V-0) of LOI and vertical burning tests. However, the flame-retardancy (LOI: 21.4% and UL 94-V: no rating) of simple epoxy resin was found to be failed the flame-retardant requirements.

• Environmental Engineering Research
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• v.21 no.1
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• pp.52-57
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• 2016

Sediment is a useful natural source but deteriorated continually by anthropogenic and industrial sources. Therefore, it is imperative to search a suitable method for improving or restoring sediment quality. Sediment has been tested to identify the effects of some external agents on a polluted area for 28 days. Chemical analysis and total viable counts (TVC) test have been conducted for 4 days interval to assess their performance. The analyses of chemical oxygen demand (COD), acid volatile sulfide (AVS), total phosphorous (T-P), total nitrogen (T-N) indicate that the chemical agents was more efficient to improve sediment quality whereas the microbial agent was more efficient for nutrient releasing from sediment. Oxygen releasing property of the chemical agent was thought to be providing with more congenial environment for the higher growth of the bacterial community than the direct application of microbial agents.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.6
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• pp.542-546
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• 1999

InP single crystal, III-V binary compound semiconductor, was grown by VGF(vertical gradient freeze) method using quartz ampoule and its electrical optical properties were investigated. Phosphorous powders were put in the bottom of quartz ampoule and Indium metal charged in conical quartz crucible what was attached at the upper side position inside the quartz ampoule. It was vacuous under the pressure of $10^5$Torr and sealed up. Indium metal was melted at $1070^{\circ}C$ and InP composition was formed by diffusion of phosphorous sublimated at $450^{\circ}C$ into Indium melt. By cooling the InP composition melt ($2^{\circ}C$~$5^{\circ}C$/hr of cooling rate) in range of $1070^{\circ}C$~$900^{\circ}C$, InP crystal was grown. The grown InP single crystals were investigated by X-ray analysis and polarized optical microscopy. Electrical properties were measured by Van der Pauw method. At the cooling method. At the cooling rate of $2^{\circ}C$/hr, growth direction of ingot was [111] and the quality of ingot was better at the upper side of ingot than the lower side. It was found that the InP crystals were n-type semiconductor and the carrier concentration, electron mobility and relative resistivity were $10^{15}$~$10^{16}/\textrm{cm}^3$ , $2\times 10^3$~$3\times 10^4{\textrm}{cm}^2$/Vsec and$2\times 10^{-1}$~$2\times 10^{-3}$/ Wcm in the range of 150K~300K, respectively.

• Journal of the Korean Ceramic Society
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• v.48 no.6
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• pp.537-542
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• 2011

Magnesium hydroxide as a non-halogen flame retardant has increasing attention due to its non-toxicity, high decomposition temperature and smoke suppressant ability during combustion. For the application of magnesium hydroxide retardant to the textile by soaking and coating method, the prerequisite for the coating is a small particle size, stable dispersion, and adhesion to the textile. The dispersion of $Mg(OH)_2$ particles and stability of the coating was checked by monitoring the change of transmittance and backscattering by varying the types of dispersion agents, binder, solvent, and $Mg(OH)_2$ source, and their compositions in the coating. The $Mg(OH)_2$ dispersion coating was applied to PET(poly(ethylene terephthalate)) non-woven textile. The physical properties are characterized by surface morphology, amount of coating, particle dispersion, and adhesion test. The flame retardant $Mg(OH)_2$ coated textile has been compared by limited oxygen index(LOI) and thermal gravimetry and differential scanning calorimetry(TG-DSC). It was found that phosphorous additive may give synergistic effect on $Mg(OH)_2$ flame retardant coating to make the flame retardant PET non-woven textile.