• 월간산업보건
• /
• s.371
• /
• pp.28-31
• /
• 2019

피부, 눈 및 상부 호흡기의 자극 가능성을 최소화하기 위해, 인산(Phosphoric acid)에 대한 직업적 노출기준 TLV-TWA를 $1mg/m^3$, 그리고 TLV-STEL을 $3mg/m^3$으로 권고하였다. 수분이 있는 상태에서 인산 먼지나 인산 케이크에 의한 피부 접촉은 특히 자극적이다. TLV-TWA의 권고수준은 산에 노출 경험이 없는 노동자들에게 인후염을 일으키는 인산의 공기 중 농도보다 낮은 수준이다. 또한 인산 노출에 순응된 노동자들에게 유발할 수 있는 농도보다는 훨씬 더 낮은 수준이다. 피부(Skin), 감작성(SEN) 또는 발암성 경고표지(Notation)를 권고하기에는 충분한 자료가 없다.

• Journal of Korean Society of Forest Science
• /
• v.85 no.1
• /
• pp.96-106
• /
• 1996

Red alder(Alnus rubra Bong.) seedlings inoculated with Frankia only or both Frankia and spores of Alpova diplophloeus(Zeller & Dodge) Trappe & Smith were grown in a greenhouse for ten weeks. The ten-week-old seedlings were fertilized with six nitrogen(N) and phosphorus(P) fertility regimes (no fertilization, 10mM $NH_4NO_3$, 50mM $NH_4NO_3$, 5mM $KH_2PO_4$, 10mM $NH_4NO_3+5mM$ $KH_2PO_4$, and 50mM $NH_4NO_3+5mM$ $KH_2PO_4$) three times a week for ten weeks. The higher N-fertilization significantly increased mycorrhiza formation by greenhouse contaminant mycorrhizal fungi, but decreased N-fixation and P concentration in nodule tissues. P-fertilization significantly increased nodule and shoot dry weight, and P concentration in plant tissues. When N was highly fertilized, however, the P-fertilization effect disappeared in nodule P concentration but doubled in leaf P concentration. A. diplophloeus inoculation significantly increased diameter growth and $CO_2$ exchange rate, but decreased leaf dry weight. Our results suggest that the higher N- or P-fertilization affect nitrogenase activity and mycorrhizal development but the effects are changed by their interactions.

• Resources Recycling
• /
• v.12 no.4
• /
• pp.38-43
• /
• 2003

Phosphate is an essential material for the growth of organisms. However. since relatively small amount is required. a large amount of phosphate is abandoned in wastes and wastewater. which contaminate the ecological environment including aquatic system. Purpose of this study is to treat especially high concentrated phosphate wastewater by use of calcium precipitation method. The pH range considered was from 6 to 12 and the maximum removal of phosphate was attained at pH 12. The con-centration of phosphate was observed to decrease rapidly until a half amount of calcium ion to its equivalent for the formation of calcium phosphate precipitate was added. which resulted in the decrease of the remaining concentration of phosphate down to 0.0027 mM. The effect of fluoride ion was examined and the concentration ratio between the phosphate and fluoride ion did not have any significant influence on the removal efficiency of phosphate. The effect of pH was also investigated. With the increasing of the pH in solution, the removal rate of phosphate was increased. Also it was investigated that the effect of fluoride on the phosphate removal was not significant.

• Journal of Korean Society of Environmental Engineers
• /
• v.30 no.6
• /
• pp.616-620
• /
• 2008

The aim of this study was to investigate the influence of phosphate on the adhesion of Escherichia coli to porous media. Column experiments were performed to examine the effect of phosphate on bacterial adhesion to quartz sand and iron-coated sand. Results showed that bacterial mass recovery in quartz sand decreased from 74.5 to 35.4% as phosphate concentration increased from 0 to 16 mg/L. This indicated that bacterial adhesion to quartz sand was enhanced with increasing phosphate concentration. This phenomenon is due to the increase of ionic strength. In contrast, the mass recovery in the coated sand increased from 2.9 to 26.0% as phosphate concentration increased. This indicated that bacterial adhesion to the coated sand was reduced with increasing phosphate concentration, due to the preoccupation of favorable adsorption sites and competitive adsorption by phosphate.

• Korean Journal of Soil Science and Fertilizer
• /
• v.15 no.2
• /
• pp.89-94
• /
• 1982

1. Solubility diagram was used to estimate Chemical form of the Soil phosphates which supply phosphorus into soil solutions under submerged condition with soils originated from granite and basalt rocks. The granite origin soils with different amounts of available phosphorus have no effect of phosphate application on rice yield, while the basalt origin soil has the big effect. 2. Almost same pattern of change in pH and concentrations of phosphorus and cations in the soil solutions during the submerging period was. shown. Almost no difference in the values was recognized between NPK and NK treatments of the granite origin soils, but the difference of the basalt origin soil was recognized. 3. it was estimated from solubility diagram that phosphorus concentration in the soil solutions was governed by phosphate applied and variscite in the soils for the early stage of submerging period, and then it became to be governed by vivianite in the soils.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2015.11a
• /
• pp.195-195
• /
• 2015

본 연구에서는 인산-망간 피막처리 공정 중에 생성되는 슬러지를 방지하기 위하여 인산-망간 화성처리액에 유기첨가제인 Tartaric acid를 첨가하여 내마모성 및 방청성 향상을 목적으로 슬러지를 방지하기 위한 인산-망간 화성피막의 특성을 연구하였다. Tartaric acid의 농도에 따른 표면 Morphology를 Scanning Electron Microscope (SEM)과 Energy Dispersive X-ray spectroscopy (EDS)을 이용하여 분석하였으며, EDS 분석을 통해 Mn, P, Fe, O, C의 성분을 확인 할 수 있었으며, 인산-망간 화성피막의 상(phase)을 확인하기 위하여 X-ray diffraction (XRD)을 분석을 통하여 $(Mn,Fe)_5H_2(PO_4)_44H_2O$으로 구성된 인산-망간 화성피막을 확인할 수 있었다. 또한 Tartaric acid의 농도에 따른 인산-망간 피막의 내마모 시험(Ball on disc) 및 경도시험을 실시하여 기계적인 특성 및 슬러지의 양에 대하여 분석하였다.

• Proceedings of the KAIS Fall Conference
• /
• 2008.11a
• /
• pp.400-402
• /
• 2008

본 연구는 오염토양 내 구리를 효과적으로 고정화시키는 조건을 찾고자 고정화제의 주입농도를 변화시켜가며 실험을 진행하였으며, 실험결과 고정화제의 주입농도가 높을수록 구리제거효율도 높아지는 것으로 나타났으며 3mole의 인산염을 주입했을 때 98%이상의 높은 제거효율을 보였다. 또한 잔류인의 농도를 낮추고 고정화반응을 촉진시키기 위해 알칼리제를 투입하였을 때, 알칼리제의 농도가 높을수록 구리오염 농도와 잔류인의 농도가 더욱 낮아짐을 알 수 있었다.

• Food Science and Preservation
• /
• v.19 no.2
• /
• pp.216-222
• /
• 2012

The optimum annealing conditions of corn starch slurry were studied for RS4 type resistant starch production by phosphorylated cross-linking. When a corn starch slurry was cross-linked by using phosphate salts (STMP/STPP mixture) in the presence of 0.9%, 1.2% and 1.5% NaOH/st.ds, a high concentration of NaOH resulted in a rapid increase of the RS contents at the early reaction stage. However, similar RS contents were obtained after 12 h of cross-linking regardless of NaOH concentrations. The annealing treatment was conducted under various conditions such as pH between 2-10, temperature $40-60^{\circ}C$, time 0-14 h followed by phosphorylated cross-linking. The lower slurry pH was for the annealing treatment, the higher RS contents were obtained after cross-linking. When the slurry annealed for various period of time and temperature, a maximal amount of RS was formed after 2 h of annealing at $50^{\circ}C$ of annealing temperature of the starch slurry (pH 2.0). Therefore, an optimal annealing conditions at pH 2.0 and $50^{\circ}C$ for 2 h were proposed under the cross-linking conditions of sodium sulfate 10%/st.ds, NaOH 1.2%/st.ds and 12 h of the reaction time. The RS contents were linearly increased with the increase of phosphate salt addition. The RS4 prepared under the optimal conditions contained RS 72.3% and its phosphorus content was 0.36%/st.ds, which was below the limit (0.4%/st.ds) of modified starch by Korea Food Additives Code.

• KSBB Journal
• /
• v.4 no.3
• /
• pp.259-265
• /
• 1989

In a batch fermentation process using carrot cell suspension culture, the effect of initial concentration of limiting nutrients(glucose and phosphate) on the specific growth rate and cell yield was investigated. The period of exponential growth is about 2 days and the consumption of glucose and phosphate in culture medium was very small when the initial concentrations of glucose and phosphate are 1.49g/1 ~ 3.01g/l and 0.08 ~ 0.32mM respectively. The specific growth rate of cells ranged from TEX>$0.15\;day^{-1}$ to $0.3\;day^{-1}$ irregularly. And the ratio of the initial concentration of glucose to phosphate did not affect the specific growth rate and the cell yield. The increase on cells had linear relationship with the consumption of limiting nutrients. Therefore, the increase of cells was found to be more influenced by the concentration of glucose than that of phosphate.

• 한국생물공학회:학술대회논문집
• /
• 2001.11a
• /
• pp.586-589
• /
• 2001

In this study, phosphate was produced through the solublization of hydroxyapatite and rock phosphate by Pantoea agglomerans, and it was examined the possibility of solublizing insoluble phosphate salt by immobilized P. agglomerans on Ca-alginate bead as support. 520mg/L of phosphate was solublized when P. agglomerans was cultured in HY meclium at $30^{\circ}C$, pH7, 100rpm, during 48hours culture. And solublized phosphate amount was 86.09mg/L when hydroxyapatite in the HY medium was exchanged to rock phosphate. In case of being used immobilized P. agglomerans. 740mg/L of phosphate was solublized in the HY medium, during 120hrs in the same condition. And 182mg/L of phosphate was solublized when rock phosphate was added instead of hydroxyapatite.