• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.1067-1070
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• 1997

Imunoglobulins from bovine plasma proteins were isolated by IMAC which $Cu^{2+}$ was chelated on a chelating sepharose fast flow gel. Most plasma proteins were eluted by 1st (0.01 M $Na_2HPO_4$, 0.5 M NaCl, pH 4.0) and 2nd elution buffers (0.01 M imidazol). According to the reverse phase HPLC analysis, it was found that proteins which were eluted by 1st elution buffer were mainly composed of serum albumin, while most IgG and transferrin were eluted by 2nd elution buffer. When protein fractions obtained by 2nd elution buffer was applied to ultra filtration system (molecular weight cut off: 100 kD), IgG was further purified. These results indicate that IMAC is an excellent tool for isolating imunoglobulins from plasma proteins.

• Journal of Radiation Protection and Research
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• v.10 no.2
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• pp.113-121
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• 1985

For the safety assessment of radwaste treatment and disposal, the leaching characteristics of $Cs^+\;and\;Sr^{++}$ from the cement-solidified radwastes was investigated by means of the survey and analysis of the activity leach rate and cumulative leach fraction of $^{137}Cs\;and\;^{90}Sr$ leaching from solidified radwastes. The cylindrical cement-solidified samples were made by the sodium silicate method and neutralization method changing the mole density of simulated liquid radwaste, type of cement, adding material and concentration of boric acid. The leaching study was carried out by the method using simulated PWR concentrated liquid radwaste solidified in cement that had been processed following the recommendations of IAEA. All the experimental results are in well accordance with the research data reported previously, but the watertight cement-solidified radwastes show rather high leach rate of radioactivity. It is learned, therefore, that the watertight cement is not adequate as the material for the solidified radwastes.

• The Journal of Engineering Geology
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• v.17 no.3
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• pp.419-424
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• 2007

The contents were investigated by the monitoring survey from the soils and tailings caused by numerous abandoned mines in Korea. Cause heavy metals due to abandoned metal mines are raising significant environmental problems. But it is an important key such as a leaching and a transfer mechanism to evaluate contamination levels caused by abandoned mines. In this study the column test was carried in order to calculate a leaching level from soils and tailings. It was demonstrated that the leaching of Pb, Cd and Mn was expressed with similar behaviors and that of As and Cu was expressed with similar behaviors. For Zn, the leaching behavior was shown a serious leaching level with 40 mg/kg during the 45days. This was explained by Zn high contents of soils Zn in a natural world and ORP conditions where the leaching of Zn was occurred easily. Hence it was necessary that the survey of ORP was a key as well as total contents for the management of abandoned metal mines. We could estimate the chemical forms of heavy metals using the physical index such as ORP and pH and reduce the risk from heavy metals caused by abandoned metal mines.

• Journal of the Mineralogical Society of Korea
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• v.31 no.3
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• pp.137-147
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• 2018

The aim of this study was to leach penalty elements, such as Bi and As, effectively through microwave leaching of a gold concentrate sample containing penalty elements with nitric acid solution. For this purpose, the time effect of microwave leaching, nitric acid concentration effect, and sample addition effect in a microwave were examined. The experiment, demonstrated that the leaching rate of penalty elements increased as microwave leaching time and nitric acid concentration increased and concentration addition decreased. When a microwave heating experiment was carried out on the concentrate and ore minerals, Bi was removed by as much as 90%, and the phase of arsenopyrite was transformed in the order of arsenopyrite (FeAsS), pyrrhotite (FeS), and hematite ($Fe_2O_3$). When the X-ray diffraction (XRD) analysis was carried out with solid residue, elemental sulfur and anglesite were identified. The intensity of the XRD peaks of elemental sulfur and anglesite increased, and the peaks were sharper when the microwave leaching time was 12 min instead of 1 min, the nitric acid concentration was 4 M in rather than 0.5 M, and the concentration addition was 30 g rather than 5 g. This was probably because more elemental sulfur and anglesite were generated in the leaching solution as the leaching efficiency increased. Bi can be leached as valuable elements in the leaching solution through microwave leaching processes while they are released to the environment through a microwave heating processes.

• Food Engineering Progress
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• v.13 no.4
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• pp.262-268
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• 2009

A dark brownish pigment in the crude polysaccharide from Auricularia auricula was adsorbed by activated charcoal. The leaching of the pigment adsorbed on activated charcoal and regeneration of activated charcoal used was investigated with eight kinds of solvents. The highest leaching capacity was obtained with the alkaline solution (KOH). The optimum volume of 1 M KOH solution per activated carbon was 45 mL/g, and the treatment for 10 min during single stage leaching was sufficient to achieve the leaching equilibrium. Second-order kinetic model provided the best fitting for the pigment leaching. The pigment leaching capacity of 88.9% was obtained by seven times of treatment with 1 M KOH solution at 25$^{\circ}C$, while at 95$^{\circ}C$, leaching capacity of 82.6% was achieved with single stage alone showing the significant increase of leaching capacity with increasing temperature. The regenerated activated charcoal was nearly as effective as fresh activated charcoal in pigment adsorption of crude polysaccharide from Auricularia auricula.

• Nuclear Engineering and Technology
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• v.8 no.4
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• pp.231-242
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• 1976

The effects of temperature and pressure of leaching water on the leaching of radionuclides from bitumen-waste products were studied. The principal results are as follows: The fraction of $^{90}$ Sr and $^{137}$ Cs leached for periods of up to 120 days at 8atm was 2.1$\times$10$^{-6}$ ($\textrm{cm}^2$/g)$^{-1}$ , day$^{-1}$ and 6.02$\times$10$^{-5}$ ($\textrm{cm}^2$/g)$^{-1}$ day$^{-1}$ respectively and at 5$^{\circ}C$, 1.7$\times$10$^{-5}$ ($\textrm{cm}^2$/g)$^{-1}$ day$^{-1}$ and 4.01$\times$10$^{-5}$ ($\textrm{cm}^2$/g)$^{-1}$ day$^{-1}$ respectively. These values were lower than those in atmospheric pressure and room temperature. No diffence in the leaching rate with sea and distilled water was observed for the bitumen-waste products containing 40wt% salts. It appears that these results could be saved by improving safety in the dumping of sea. The effect of the softening point of pure asphalt or bitumen-waste product by $^{60}$ Co irradiation was increased with increasing total dose. Irradiation of asphalts at a total dose of 5.8$\times$10$^{8}$ rad showed no evidence of volume and caused no swelling. The functional groups of blown asphalt by infrared spectra are also identified.

• Journal of Ginseng Research
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• v.10 no.1
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• pp.80-93
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• 1986

The tail portion of dried 6-year old white ginseng was extracted and sugars and nitrogen compounds were also evaluated for chemical properties depending on varying conditions of extractions. The factors studied were extraction temperature in the range of 70-$100^{\circ}C$, ethanol concentration of 0-90% and the times of extractions which was taken 8 hours per each extraction in water at $80^{\circ}C$. For the effect of ethanol concentration in the extraction solvent, it was found that the amounts of free, reducing and total sugars and starch recovered in extract were almost linearly decreased along with the increase of concentration and the nonprotein nitrogen accounted over 84% of total nitrogen in extract. As ethanol concentration became increased, extractions of total nitrogen and water souluble nonprotein nitrogen were decreased especially in 90% ethanol. For the extraction temperature, all the sugar fractions with water and 70% ethanol except free sugar have tended to increase along with the temperature raised from 70 to $100^{\circ}C$ and it was found there is little changes of nitrogen compounds in the temperature range except a rapidly increase in water soulble protein at $100^{\circ}C$. For the times of extractions, showed that most of extractable compounds were extracted in 3 times of extractions with water at $80^{\circ}C$. It was shown that more than 95f) of sugars and 80% of nitrogen compounds were yielded with water extraction. Accordingly it was efficient to extract with water or 70% ethanol in 3 times in terms of !actor and energy consumption.

• Journal of Korea Water Resources Association
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• v.48 no.1
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• pp.9-21
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• 2015

This study examined pollution level of sediment in Sookchun lake, and studied dredging validity by examining phosphorous release characteristics on surface polluted soil. Total phosphorous, the principal cause of algal blooms, exceeded dredging assessment standards regarding Daechung lake (1.5 mg/g) at all points. Also at all points, total nitrogen exceeded the dredging assessment standard regarding Paldang Lake (1.1 mg/g), but fell short of the standard regarding Daechung lake (3.0 mg/g). Dredging zone was suggested in this study is Chuso water body (WS-6~WS-12) in Sookchun lake. In relation to sediment pollution levels measured at different depths, LOI tended to decrease as it became deeper. The concentrations of T-N varied depending upon the depth as well as points, but no regular pattern was observed. The depth and site did not significantly influence T-P. From the results of phosphorous release tests, it was shown that total phosphorous release flux was calculated to be $7.2{\sim}15.4mg/m^2/d$ for anaerobic condition, $0.5{\sim}2.0mg/m^2/d$ for aerobic condition and $2.0{\sim}4.1mg/m^2/d$ for facultative condition. Release flux and T-P concentration of surface sediments had positive correlation ($R^2$ 0.7871). And The corelation between release flux and DO condition in reactor had strong negative correlation ($R^2$ 0.8824).

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.2
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• pp.110-114
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• 1988

Salt penetration, moisture effluence and elution of calcium of radish were investigated during salting in $3{\sim}10%$ salt solution. The desirable salt concentration of kimchis were also evaluated by sensory method. Among 20 samples collected from domestic and commercially prepared kimchis, 8 samples were found to be desirable salt concentration having the concentration range of $1.2{\sim}2.2%$. Moisture and calcium diffused from radish tissue were increased as the salt concentration increased. The proper salting time were estimated to be two hours at 3%, one hour at 5% and 30 minutes at 10% of salt at $20^{\circ}C$. Salting at high concentration shortened the salting time but brought a significant calcium loss.

• 연구논문집
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• s.28
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• pp.161-172
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• 1998

In the recycling industry, the recuperation of zinc from Electric Arc Furnace dust by the Waelz process generates important quantities of slag. This slag presents good mechanical properties, and for the most siliceous slag. a high stability which would enable its use by total or partial substitution of certain granulates in civil engineering Our study (within the framwork of a European programme cofunded by the European Commission-DGXII) concerns the physico-chemical and mineralogical characterization and leaching behaviour of several types of Waelz slag. The leaching tests are regulatory tests and specific characterization tests of leaching behaviour. They take into account the influence of several main parameters of the valorization scenarios envisaged for the slag(e.g. pH, Redox potential, chemical nature of the leachant, type of contact-liquid/ solid etc.).