• Journal of Life Science
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• v.21 no.5
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• pp.706-712
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• 2011

Metabolism of $^3H$-castasterone in the presence of $^{32}P$-ATP was examined by an enzyme solution prepared from A. thaliana after a reversed phased HPLC, after which a polar metabolite labeled by both $^3H$ and $^{32}P$ was obtained, suggesting that $^3H$-CS is phosphorylated by $^{32}P$-ATP. To elucidate the structure of the phosphorylated CS, the same enzyme assay was carried out with non-isotopes labeled CS and ATP. In GC-MS analysis the metabolite gave a molecular ion at m/z 664 as a bismethanboronate, suggesting the metabolite is a CS phosphate. Treatment of wheat germ acid phosphatase that hydrolyzed phosphoester bond gave the same mass spectrum and GC retention time in GC-MS analyses, confirming that the metabolite is phosphorylated CS. This is the first example of phosphorylated conjugates of CS in plants.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3553-3558
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• 2014

The reduced graphene oxide(rGO)/aluminum phosphate($AlPO_4$)-coated $LiMn_{1.5}Ni_{0.5}O_4$ (LMNO) cathode material has been developed by hydroxide precursor method for LMNO and by a facile solution based process for the coating with GO/$AlPO_4$ on the surface of LMNO, followed by annealing process. The amount of $AlPO_4$ has been varied from 0.5 wt % to 1.0 wt %, while the amount of rGO is maintained at 1.0 wt %. The samples have been characterized by X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. The rGO/$AlPO_4$-coated LMNO electrodes exhibit better cyclic performance compared to that of pristine LMNO electrode. Specifically, rGO(1%)/$AlPO_4$(0.5%)- and rGO(1%)/$AlPO_4$(1%)-coated electrodes deliver a discharge capacity of, respectively, $123mAhg^{-1}$ and $122mAhg^{-1}$ at C/6 rate, with a capacity retention of, respectively, 96% and 98% at 100 cycles. Furthermore, the surface-modified LMNO electrodes demonstrate higher-rate capability. The rGO(1%)/$AlPO_4$(0.5%)-coated LMNO electrode shows the highest rate performance demonstrating a capacity retention of 91% at 10 C rate. The enhanced electrochemical performance can be attributed to (1) the suppression of the direct contact of electrode surface with the electrolyte, resulting in side reactions with the electrolyte due to the high cut-off voltage, and (2) smaller surface resistance and charge transfer resistance, which is confirmed by total polarization resistance and electrochemical impedance spectroscopy.

• Journal of Animal Science and Technology
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• v.45 no.3
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• pp.491-498
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• 2003

The purpose of this study is to observe purification and properties of osteopontin(OPN) from bovine milk. The purification of osteopontin from bovine milk was performed by using ion-exchange and hydrophobic chromatography. SDS-PAGE analysis revealed that the protein migrated at Mw. 60,000. NH2-terminal sequence analysis of the first seven amio acids revealed the protein to be identical to that previously reported for bovine OPN. 35-wk-old chickens, including 3 Single Comb White Leghorn (SCWL), were used to produce egg yolk antibody(IgY) against OPNas a antigen. However, the anti-OPN antibody activities determined by ELISA. Immunological assy of OPN in milk was performed using radial immunodiffusion test based on the standard curve of pure OPN. The radial precipitation lines of four different milk samples indicated that the concentrations of OPN in the milk samples were within the range of 31.7 to 39.7${\mu}g$/ml. On inhibition with OPN on precipitation of calcium phosphate, OPN was slightly higher than casein phosphopeptide(CPP) and poly-glutamic acid.

• Journal of the Korean Chemical Society
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• v.27 no.5
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• pp.361-367
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• 1983

The selective separation and the quantitative recovery of uranium from Korean monazite sand have been studied by anion-exchange chromatography. It has been shown that method of anion-exchange chromatography under controlled conditions of elution can be applied to the production of relatively high purity of Uranium Oxide from monazite sand. Under the optimum separation conditions, the recoveries from standard sample were up to 99.3% as $U_3O_8$ on sulfate form anion resin bed and 99.2% as $U_2O_3{\cdot}P_2O_7$ on phosphate form anion resin bed. The possibility of recovering uranium from the monazite sulfate solution using a strong base anion exchange resin-Amberlite IRA-900. Uranium was successfully recovered about 92 percent. Phosphate ion did not seem to interfere with the process.

• Korean Journal of Microbiology
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• v.8 no.1
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• pp.41-51
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• 1970

In previous paper, it was reported that antibiotic substance such as tetracycline and streptomycin were produced by S'. albus subsp. and S'. globosus. And increase of mycelial growth of two strains, antibiotic production, and changes of pH range are extended to approximately 110-130 hrs in fermenting medium, there-after they decreased with culture period exception of pH range. Two Streptomyces spp. required commonly 4-5% starch as carbon sources and 1.5-2.0% soybean meal as nitrogen sources. However, 0.005-0.01M potassium phosphate dibasic, calcium carbonate (6mg/ml in S.albus subsp. and 2mg/ml in S. globosus), 0.01-0.03M, magnesium sulgate and 0.01M ferric chloride showed as optimal concentration for the growth of 2 strains. Mineral compoments such as zinc, manganese, cobalt, sodium and copper at the level of 10$^{-4}$ -10$^{-6}$ M were observed. Especially, zinc ion showed toxicity to the growth of 2 strains at 0.005M. In relation with pH, there is a little difference in mycelial growth with cultural initial pH.

• Journal of the korean society of oceanography
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• v.31 no.2
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• pp.55-63
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• 1996

Distribution of suspended particulate matter, dissolved oxygen and major inorganic nutrients along a meridional section ($126^{\circ}$ 33' E) in the Cheju Strait is described along with the hydrographic and current data obtained during April 25-27, 1995. The current measurements was conducted using a vessel-mounted Acoustic Doppler Current Profiler (ADCP). Repeated coverage along an ADCP transect during 25 hours allows to calculate the daily mean along- and cross-strait currents. Measured material concentrations and the mean current speed were used to estimate the flux density (cencentration times current speed) of materials. Two types of depth distibution of flux densities were observed. for nitrate and suspended particulate matter, the depth distribution pattern of materials determines those of flux densities. However, flow patterns determine those of flux densities for dissolved oxygen, phosphate and silicic acid. The total along-strait water volume transport is about 0.3 Sv (1Sv $10^{6}$ $m^{3}/s^{-1}$). The total along-strait material transports are estimated to be 3.1 $${\times} $10^{5}$ $g/s^{-1},$ 2.4 ${\times}$ $10^{6}\;g/s^{-1},$ 7.I ${\times}$ $10^{2}\;mol/s^{-1},$ 3.I ${\times}$ $10\;mol/s^{-1},$ 1.7 ${\times}$ $10^{3}\;mol/s^{-1}$ for suspended particulate matter, dissolved oxygen, nitrate ion, silicic acid and phosphate ion, respectively.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1491-1494
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• 2011

Lithium vanadium phosphate, $Li_3V_2(PO_4)_3$ was prepared by a simple solid state route. It was found that making a fine powder of $Li_3V_2(PO_4)_3$ by the mechanical milling is very effective for increasing the insertion/extraction of lithium from $Li_3V_2(PO_4)_3$ structure. In charge/discharge test, the ball-milled $Li_3V_2(PO_4)_3$ sample exhibited a higher initial discharge capacity of 174 mAh/g in the voltage range of 3.0-4.8 V, compared with pure $Li_3V_2(PO_4)_3$ sample (152 mAh/g). Furthermore, the ball-milled $Li_3V_2(PO_4)_3$ presented not only higher cycle retention rate after 50 cycles, but also better rate capability compared with pure sample in the whole region (0.1-7 C).

• Microbiology and Biotechnology Letters
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• v.21 no.4
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• pp.373-380
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• 1993

When the cells of yeast K35 were immobilized in Ca-alginate gel, cell concentration and viability decreased as alginate concentration increased. Considering the results, 2% (w/v) Ca-alginate concentration would be suitable. Among various concentrations of additives and cross-lin-king agent, the addition of 1.67% (w/v) of bentonite together with 0.33% (v/v) of glutaraldehyde (ABG bead) resulted in the highest ethanol production of 1.8%(w/v), using YPD medium containing 2% glucose. ABG bead seemed to be more resistant to phosphate ion than Ca-alginate bead. 0.33%(w/v) of phosphate was a proper concentration for the ethanol production by ABG bead. Scanning electron microscopic observation depicted that the immobilized cells on the bead surface were coated by alginate gel and that the cells in the internal bead were cross-linked with alginate matrix. When repeated-batch culture was performed with ABG bead for 40 days in a packed-bed reactor, ethanol concentration of about 90~110 g/l-gel was maintained. Cell viability was maintained around 70%, and outgrowing cell concentration was below 6.3% of total cell concentration. Consequently, the results showed that ABG head was a potential carrier for continuous production of ethanol compared to conventional Ca-alginate bead.

• Analytical Science and Technology
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• v.5 no.1
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• pp.33-39
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• 1992

THF-based crown-4 of 16-membered rings having tetrahydrofuran unit was synthesized by an acid-catalyzed condensation of furan and acetone followed by hydrogenation in an effort to obtain highly elective ionophores for lithium ions. The new ionophore was compared with previously reported ionophores under similar measurement conditions with the same plasticizer, tris(2-ethylhexyl) phosphate in poly(vinyl chloride)(PVC) membrane electrodes. Separate solution method was used to determine relative selectivity coefficients for the electrode. The selectivity coefficients($K_{LiM}^{POT}$) of lithium over ammonium, alkali and alkaline earth metal ions go from about $2.4{\times}10^{-1}$ to $2.3{\times}10^{-4}$ to working range and pH dependence have also been studied.

• Journal of the Korean Chemical Society
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• v.27 no.2
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• pp.111-116
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• 1983

Three component $Ag_2S-PbS-PbWO_4$ electrodes have been prepared and evaluated for sensitivity to tungstate. The 51.71 : 16.64 : 31.65(w/w%) composition is superior in terms of potentiometric response, stability, rapidity of response and reproducibility. Testing was done over the concentration range $10^{-1}~10^{-4}M WO_4^{2-}$ in $0.1F-NH_4Ac-NH_4OH$ buffer at pH 8.00 with constant ionic strength. The quality of response is similar to that of corresponding phosphate-sensing electrode. Many common ions interfere.