• Fire Science and Engineering
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• v.29 no.6
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• pp.13-19
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• 2015

This study was performed to test the combustive properties of Pinus rigida specimens treated with phosphorus (P) and nitrogen (N) additives. Each Pinus rigida specimen was painted three times with 15 wt% P-N additive solutions at room temperature. After drying the treated specimens, the combustion properties were examined using a cone calorimeter (ISO 5660-1). The time to ignition (TTI) for the treated specimens was 90 to 148 s except for the specimen treated with PP/$4NH_4^+$, and the time to flameout (TF) was 556 to 633 s, which was longer than that of virgin plate. While the The specimens treated with P-N additives showed 12.5 to 43.4% higher mean heat release rate ($HRR_{mean}$) and 11.8 to 43.1% higher total heat release (THR) than virgin plate. The effective heat of combustion (EHC) was by 2.9 to 17.5% lower than that of virgin plate. It can thus be concluded that the combustion-retardation properties were partially improved compared to those of virgin plate.

• Asian Journal of Turfgrass Science
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• v.4 no.1
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• pp.5-11
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• 1990

Korean Lawn. Zoysia japonica Steud. is the type of a perennial warm-season turfgrass keeping green leaf color for 5 months from May to September in natural condition in Korea. This Studies were carried out to obtain the effects of N-P-K fertilization, regrowth capacity after mowing and chlorophyll contents on prolongation of the green leaf color period in Zoysia japonica Steud turfgrass areas. The results obtained are summarized as follows ; 1.The effects of nitrogen fertilizer application in Zoysia japonica Steud, turfgrass areas were affected on regrowth ability after mowing green color of leaf canopies and chlorophyll contents, respectively(P<.05) 2.A experimental plots which applied 51 g/m$^2$/10 weeks of N$_3$P$_1$K$_1$fertilizer, there were high significant effects on prolongation of the green leaf color period and the plots of phosphorus and potassium had additive effects. 3.Prolongation of the green leaf color period to the last of October was obviously possible by slow degrees in proportation to increment of the fertilizer. However, it is interpreted that more prolongation of the green period is impossible with N-P-K fertilization and irrigation treatments. unless the intermediate turfgrasses between $C_3$ and $C_4$plants must be found and bred.

• Current Photovoltaic Research
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• v.2 no.4
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• pp.147-151
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• 2014

A boron doping process using a boron tri-bromide ($BBr_3$) as a boron source was applied to form a $p^+$ emitter layer on an n-type mono-crystalline CZ substrate. Nitrogen ($N_2$) gas as an additive of the diffusion process was varied in order to study the variations in sheet resistance and the uniformity of doped layer. The flow rate of $N_2$ gas flow was changed in the range 3 slm~10 slm. The sheet resistance uniformity however was found to be variable with the variation of the $N_2$ flow rate. The optimal flow rate for $N_2$ gas was found to be 4 slm, resulting in a sheet resistance value of $50{\Omega}/sq$ and having a uniformity of less than 10%. The process temperature was also varied in order to study its influence on the sheet resistance and minority carrier lifetimes. A higher lifetime value of $1727.72{\mu}s$ was achieved for the emitter having $51.74{\Omega}/sq$ sheet resistances. The thickness of the boron rich layer (BRL) was found to increase with the increase in the process temperature and a decrease in the sheet resistance was observed with the increase in the process temperature. Furthermore, a passivated emitter solar cell (PESC) type solar cell structure comprised of a boron doped emitter and phosphorus doped back surface field (BSF) having Ni/Cu contacts yielding 15.32% efficiency is fabricated.

• Journal of Animal Environmental Science
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• v.17 no.sup
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• pp.35-42
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• 2011

This work was conducted to investigate the effect of dietary phytase on growth performance and excreta excretion of growing-finishing pigs for 7 days. Eighty three crossbreeds (Yorkshire ${\times}$ Landrace ${\times}$ Duroc) of growing-finishing pigs were used in this work, and divided into 6 treatments. Six treatments were compared in a $2{\times}2$ factorial arrangement with 2 groups (5 replications/group, 8 head/replications) with the additive phytase and 3 groups(growing I, II and finishing phase) with growing phases. Initial weights with growing phases were $58.6{\pm}3.9$. $83.2{\pm}3.8$ and $111.4{\pm}5.4kg$, respectively. Body weight gain was high in phytase treatment (P<0.01) and low at finishing phase. Feed conversion ratio was high in no phytase treatment and at finishing phase (P<0.05). Feed and water intakes have no significant difference with phytase existence and growing phases. Feces excretion decreased with growing phase (P<0.05), and was low at phytase treatment (P<0.05). There was no significant difference on urine excretion (P>0.05). Nitrogen (N) and phosphorus (P) intake was not found significant difference with phytase and growing phases. N excretion had no significant difference on phytase existence and growing phase (P>0.05), but P excretion decreased at phytase treatment (P<0.05). N and P excretion ratio was low at phytase treatment (P<0.05). Finally, dietary phytase resulted in improvement of growth performance and reduction of excreta excretion of growing-finishing pigs.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.3
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• pp.131-137
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• 1986

Korean lawn, Zoysia japonica STEUD, is the type of a perennial warm-season lawn grass that has a naturally green period during 5 months from May to September. This study was carried out to detect the effects of N-P-K fertilization, regrowth capacity after mowing and chlorophyll contents on prolongation of the green period in Zoysia japonica grasslands. The results obtained are summarized as follows: 1. The effects of nitrogen fertilizer application on Zoysia japonica grasslands were affected on regrowth capacity after mowing, green color of leaf canopies and chlorophyll contents, respectively. 2. A the experimental plots which applied 45g/$m^2$/10 weeks of $N_3$ fertilizer, there were high significant effects on prolongation of the green period and the plots of phosphorus and potassium had additive effects. 3. Prolongation of the green period to the last ten days of October was obviously possible by slow degrees in proportion to increment of N-P-K fertilization. 4. However, it is interpreted that more prolongation of the green period is impossible with N-P-K fertilization and irrigation treatments, unless the intermediate turfgrasses between $C_3$ and $C_4$ plants must be found and bred.