• Journal of Korean Dental Science
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• v.3 no.1
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• pp.32-38
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• 2010

Objective : To evaluate the relationship between the dose of Clodronate and serum level of alkaline phosphatase (ALP), calcium (Ca), and phosphate (PO4) during orthodontic tooth movement MaterialS and MethodS: A total of 18 sex-matched Wistar rats (weight=180~230g, mean age=8 weeks) were allocated into the 2.5mM Clodronate (2.5C) group, 10mM Clodronate (10C) group, or control group (n=6 for each group). After the application of a nickel-titanium closed coil spring (force of 60g) between the upper central incisors and first molars (UFM), 2.5C, 10C, or saline was injected every third day into the subperiosteum of the alveolar bone adjacent to UFM for the experimental and control groups. The animals were sacrificed 17 days later. Trunk blood was quickly collected into a heparinized tube and centrifuged at 2,000 rpm for 20 min. The plasma was used for the biochemical assays of the serum level of ALP, Ca, and PO4. Kruskall-Wallis test and Mann-Whitney test with Bonferroni correction were performed for the statistical analyses. Results : Dose-dependent increase in the level of ALP (P<0.01) and decrease in the level of Ca (P<0.001) were observed among the control, 2.5C, and 10C groups. Although there was no significant difference in PO4 between the 2.5C and 10C groups, the 10C group showed a significantly higher level of PO4 than the control group (P<0.01). Conclusion : Since Clodronate induced significant dose-dependent change in the serum level of ALP, Ca, and PO4 during orthodontic tooth movement, orthodontists should consider these biochemical markers not only as a diagnostic tool for bone turnover rate but also as a monitoring tool for orthodontic tooth movement.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.464-472
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• 2014

The Codex Committee of Contaminants in Food (CCCF) has been discussing a new standard for arsenic (As) in rice since 2010 and a code of practice for the prevention and reduction of As contamination in rice since 2013. Therefore, our current studies focus on setting a maximum level of As in rice and paddy soil by considering bioavailability in the remediation of As contaminated soils. This study aimed to select an appropriate single chemical extractant for evaluating the mobility of As in paddy soil and the bioavailability of As to rice. Nine different extractants, such as deionized water, 0.01 M $Ca(NO_3)_2$, 0.1 M HCl, 0.2 M $C_6H_8O_7$, 0.43 M $HNO_3$, 0.43 M $CH_3COOH$, 0.5 M $KH_2PO_4$, 1 M HCl, and 1 M $NH_4NO_3$ were used in this study. Total As content in soil was also determined after aqua regia digestion. The As extractability of the was in the order of: Aqua regia > 1 M HCl > 0.5 M $KH_2PO_4$ > 0.43 M $HNO_3$ > 0.2 M $C_6H_8O_7$ > 0.1 M HCl > 0.43 M $CH_3COOH$ > deionized water > 1 M $NH_4NO_3$ > 0.01 M $Ca(NO_3)_2$. Correlation between soil extractants and As content in rice was in the order of : deionized water > 0.01 M $Ca(NO_3)_2$ > 0.43 M $CH_3COOH$ > 0.1 M HCl > 0.5 M $KH_2PO_4$ > 1 M $NH_4NO_3$ > 0.2 M $C_6H_8O_7$ > 0.43 M $HNO_3$ > 1M HCl > Aqua regia. BCF (bioconcentration factor) according to extractants was in the order of : 0.01M $Ca(NO_3)_2$ > 1 M $NH_4NO_3$ > deionized water > 0.43 M $CH_3COOH$ > 0.1 M HCl > 0.43 M $HNO_3$ > 0.2 M $C_6H_8O_7$ > 0.5 M $KH_2PO_4$ > 1 M HCl > Aqua regia. Therefore, 0.01 M $Ca(NO_3)_2$ ($r=0.78^{**}$) was proven to have the greatest potential for predicting As bioavailability in soil with higher correlation between As in rice and the extractant.

• KOREAN POULTRY JOURNAL
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• v.24 no.6 s.272
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• pp.131-135
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• 1992

칼슘과 인은 동물체내에 존재하는 광물질로 칼슘이 대략 $1.6{\~}2.0{\%}$, 인이$0.9{\~}1.1{\%}$ 함유되어 있다. 칼슘과 인은 주로 뼈에 많이 함유되어 있는데 주로 $Ca_3(PO_4)_2$의 형태로 존재한다.

• Journal of Korean Society on Water Environment
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• v.25 no.4
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• pp.515-521
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• 2009

In this study, the applicability of $CaCO_3$ as a seed material for crystallization reaction was tested. $CaCO_3$ was ground to lesser than 425 mesh and was made to media mixed with binder. Batch experiment was to investigate the ${PO_4}^{3-}-P$ removal efficiency of different parameters such as $CaCO_3$ dosage and binder ratio, size, type and mass of media. In addition, the effect of phosphorus removal from wastewater was tested using a lab-scaled crystallization reactor. At the results of the batch test, phosphorus removals were improved with increasing $CaCO_3$ dosage and media mass but were decreased with increasing media size. Moreover, phosphorus removals were influenced by specific surface area but media type. The average T-P and ${PO_4}^{3-}-P$ removal efficiency in a lab-scaled crystallization reactor with $CaCO_3$ media for wastewater were shown to be 60.2% and 60.3% for 18 days of operation time.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.3
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• pp.223-232
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• 1995

Abstract Urea($(NH_2)_2CO$) and THAMP (Tris(hydroxymethyl) aminomethane phosphate) are new organic nonlinear optical materials (NLO) for the device application such as the frequency conversion of laser radiation. The single crystals of urea and THAMP have been grown by the falling temperature method and the temperature difference method. The crystal growth parameters were presented associated with the molphology of the grown crystals. Based on the solubility measurements, methanol was a suitable solvent for the growth of urea. The solubilities of urea have a positive temperature coefficient and the heat of solution of urea was estimated to be -2.58 kcal/mol. The grown crystals of urea have the preferential growth habit in the z-axis. Additives such as $NH_4_H_2PO_4$, KCL, $H_3PO_4$, $CaCl_2{\cdot}2H_2O$, $C_2H_5OH$ were used for the favourable growth in the x - and y-axis and the preventive growth in the z-axis. The moleratio of THAM and H3P04 for the solution of THAMP was 1 : 1. The solubilities of THAMP have a positive temperature coefficient. The heat of solution was estimated to be - 1.70 kcal/ mol.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.1
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• pp.8-14
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• 1990

Retardation and hydrodynamic dispersion coefficient necessary for model of water and solute movement in a soil were determined for horizontal soil column with different initial soil water conditions. The soil columns were compacted with sandy loam soil. The bulk density was $1,350+50kg/m^3$, and initial water contents were 0.05, 0.08 and 0.14. Advancement of 0.05% $CaSO_4$ solution was used as the standard and advancements of 0.5% KCl, $CaCl_2$ and $KH_2PO_4$ were compared. Retardation of non-reactive $Cl^-$ was related with the initial soil water content, ${\theta}n$, as ${\theta}/({\theta}-{\theta}n)$, and anion exclusion was ignored. Retardations of active $K^+$, $Ca^{{+}{+}}$ and $H_2PO_4{^-}$ were related as 1/(R+1) $^*{\theta}/({\theta}-{\theta}n)$, in which R was retardation coefficient. Measured R was 0.64 for $K^+$, 0.80 for $Ca^{{+}{+}}$ and 2.6 for $H_2PO_4{^-}$, respectively. Calculated R using Langmuir adsorption isotherm showed fair degree of applicability. Soil water diffusivity, $D({\theta}),m^2/sec$, calculated for different initial water content showed unique function as $$log(D({\theta}))=13.448{\theta}-9.288$$ Hydrodynamic dispersion coefficient of $Cl^-$ above soil water content 0.36 was similar to soil water diffusivity and decreased to near self diffusion coefficient at soil water content near 0.2. Those of $K^+$, $Ca^{{+}{+}}$ $H_2PO_4{^-}$ at soil water content of 0.38 were $5.5{\times}10^{-6}$, $2.4{\times}10^{-6}$ and $7.1{\times}10^{-7}m^2/sec$ and decreased rapidly with decreasing soil water content lower than 0.36.

• Journal of the Korean Ceramic Society
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• v.40 no.6
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• pp.608-614
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• 2003

Well developed hydroxyapatite whiskers (length 5 ${\mu}{\textrm}{m}$, diameter 0.5 ${\mu}{\textrm}{m}$) have been synthesized by the hydrolysis reaction of $\alpha$-tricalcium phosphate ($\alpha$-Ca$_3$(PO$_4$)$_2$) under pH 9.1 at 9$0^{\circ}C$ for 6 h. The effect of reaction conditions (temperature, time, pH) on the conversion of $\alpha$-tricalcium phosphate to hydroxyapatite was examined. In addition, the hydroryapatite was characterized in terms of microstructure, composition and thermal stability using XRD, SEM, ICP, and TGA instruments.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1273-1279
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• 2005

Penicillium oxalicum strain CBPS-3F-Tsa, an efficient phosphate solubilizing fungus, was evaluated for its production of organic acid in vitro and effect of inoculation on the growth promotion of Maize under greenhouse conditions. The fungus solubilized 129.1, 118.8, and 54.1 mg P/1 of tricalcium phosphate [$Ca_{3}(PO_{4})_{2}$], aluminum phosphate ($A1PO_{4}$),and ferric phosphate ($FePO_{4}$), respectively, after 72 h of incubation. Malic acid, gluconic acid, and oxalic acid were detected in the flasks supplemented with various phosphate sources [240, 146, 145 mM/1 $A1PO_{4},\;FePO_{4},\;and\;Ca_{3}(PO_{4})_{2}$, respectively] together with a large amount of malic acid followed by the other two. The effects of inoculation of P. oxalicum CBPS-3F-Tsa on maize plants were studied under pot culture conditions. P. oxalicum CBPS-3F-Tsa was inoculated to maize plants alone or together with inorganic phosphates in the form of fused phosphates (FP) and rock phosphates (RP). Inoculation of P. oxalicum CBPS-3F-Tsa increased the plant growth and N and P accumulation in plants, compared with control plants, and also had positive effects when applied with RP. The results of this study show that the fungus P. oxalicum strain CBPS-3F-Tsa could solubilize different insoluble phosphates by producing organic acids, particularly malic acid, and also improved the efficiency of RP applied to maize plants.

• Clean Technology
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• v.16 no.4
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• pp.258-264
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• 2010

This study estimated the possibility of phosphate removal characteristics to utilize EAF(electric arc furnace) slag as submarine cover material. The major phosphate removal mechanism was a certain formation of HAP precipitation occurred by the ionization reaction between $Ca^{2+}$ and $OH^-$, which were leached from the EAF Slag. Another phosphate removal mechanism was the adsortion of EAF slag surface. As a result of $PO_4{^-}-P$ removal characteristics using continuous column reactor, $PO_4{^-}-P$ concentration decreased rapidly after 3 days and 10 days later, it show under 0.5 ppm. The result as applied in real sea water, shows that the phosphate removal effects were 93~98% by the subaqueous sediment removal using the EAF slag. In conclusion, EAF slag is useful in $PO_4{^-}-P$ removal and control and it is possible to use without additional process like crush and selection.

• Korean Journal of Soil Science and Fertilizer
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• v.15 no.2
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• pp.117-127
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• 1982

Mulberry plants (Morus alba L.) were grown in pots with the following different nitrogen sources: ammonium sulphate, urea, ammonium nitrate, sodium nitrate + ammonium nitrate ($NO_3:NH_4$=2:1), and sodium nitrate. The effects of the nitrogen sources on mulberry yields, nitrogen recovery, distribution of ions and cation-anion balance (C-A) along leaf sequence and growth stage were investigated. The results were as follows: 1. Leaf yields and nitrogen recovery decreased with increasing $NO_3$-N application rates. 2. Relative cation contents in leaves in the early growth stages showed the following pattern : Na < Mg < Ca < K. However, the order of Ca and K reversed in the later stages. The order of anion contents chifted from $SO_4$ < $NO_3$ < Cl < $H_2PO_4$ in the early stages to $NO_3$ < Cl < $SO_4$ < $H_2PO_4$ in the later stages. 3. Contents of K, $H_2PO_4$, $SO_4$, $NO_3$, T-N and the sum of anion contents (${\sum}A$) were higher in upper leaves whereas Ca, Mg, Cl, the sum of cation contents (${\sum}C$) and (C-A) were higher in lower leaves. 4. When $NO_3$ in leaves decreased, Cl and K as counter-cations increased and consequently Ca decreased. 5. The (C-A) in leaves varied with leaf sequence and growth stage from 700 to 900 me/kg D.M.