• KSBB Journal
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• v.21 no.3
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• pp.181-187
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• 2006

In this study, problems related with pH control in electrokinetic(EK) bioremediation of phenanthrene contaminated soil were observed, and the effects of pH control methods on the removal efficiency were investigated to search a further application strategy. In a preliminary experiment, it was found out by flask cultivation that a certain sulfate concentration was needed to degrade phenanthrene well using Sphingomonas sp. 3Y. However, when $MgSO_4$ was used as sulfate source in EK bioremediation, the bacterial activity reduced seriously due to the abrupt decrease of pHs in soil and bioreactor by the combination of magnesium and hydroxyl ions. When another strong buffering compound was used to control the pH problem, the good maintenance of the bacterial activity and pHs could be observed, but the removal efficiency decreased largely. When a low concentration of $MgSO_4$ was added, the removal efficiency decreased somewhat in spite of the good maintenance of neutral pHs. With the addition of NaOH as a neutralizing agent, the removal efficiency also decreased because of the increase of soil pH. Consequently the selection of electrolyte composition was a very important factor in EK bioremediation and some sulfate sources suitable for both bacterial activity and contaminant degradation should be investigated.

• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.4
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• pp.227-238
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• 2013

The purpose of this study is to develop a process technology to produce high hardness drinking water which meet drinking water standard, remaining useful minerals like magnesium and calcium in the seawater desalination process while removing the sulfate ions and chloride ions. Seawater have been separated the concentrated seawater and desalted seawater by passing on Reverse Osmosis membrane (RO). Using Nano-filtration membrane (NF), We were prepared primary mineral concentrated water that sodium chloride were not removed. By the operation of electro-dialysis (ED) having ion exchange membrane, we were prepared concentrated mineral water (Mineral enriched desalted water) which the sodium chloride is removed. We have produced the high hardness water to meet the drinking water quality standards by diluting the mineral enriched desalted water with deionized water by RO. Reverse osmosis membranes (RO) can separate dissolved material and freshwater from seawater (deep seawater). The desalination water throughout the second reverse osmosis membrane was completely removed dissolved substances, which dissolved components was removed more than 99.9%, its the hardness concentration was 1 mg/L or less and its chloride concentration was 2.3 mg/L. Since the nano-filtration membrane pore size is $10^{-9}$ m, 50% of magnesium ions and calcium ions can not pass through the nano-filtration membrane, while more than 95% of sodium ions and chloride ions can pass through NF membrane. Nano-filtration membrane could be separated salt components like sodium ion and chloride ions and hardness ingredients like magnesium ions and calcium ions, but their separation was not perfect. Electric dialysis membrane system can be separated single charged ions (like sodium and chloride ions) and double charged ions (like magnesium and calcium ions) depending on its electrical conductivity. Above electrical conductivity 20mS/cm, hardness components (like magnesium and calcium ions) did not removed, on the other hand salt ingredients like sodium and chloride ions was removed continuously. Thus, we were able to concentrate hardness components (like magnesium and calcium ions) using nano-filtration membrane, also could be separated salts ingredients from the hardness concentration water using electrical dialysis membrane system. Finally, we were able to produce a highly concentrated mineral water removed chloride ions, which hardness concentration was 12,600 mg/L and chloride concentration was 2,446 mg/L. By diluting 10 times these high mineral water with secondary RO (Reverse Osmosis) desalination water, we could produce high mineral water suitable for drinking water standards, which chloride concentration was 244 mg/L at the same time hardness concentration 1,260 mg/L. Using the linked process with reverse osmosis (RO)/nano filteration (NF)/electric dialysis (ED), it could be concentrated hardness components like magnesium ions and calcium ions while at the same time removing salt ingredients like chloride ions and sodium ion without heating seawater. Thus, using only membrane as RO, NF and ED without heating seawater, it was possible to produce drinking water containing high hardness suitable for drinking water standard while reducing the energy required to evaporation.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.43-52
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• 1988

One-year-old seedlings of Ginkgo biloba were treated with various simulated acid rains(pH 2.0, pH 3.0, pH 9.0 and pH 5.0) to examine the effects of simulated acid rain on the chemical properties of the tested soil. The seedlings were grown in a pot($4500cm^3$)containing one of three different soils(nursery soil, mixed soil and sandy soil). Simulated acid rain was made by diluting sulfuric and nitric acid solution($H^1SO^4$ : $HNO^3$ =3 : 1, V/V) with tap water and tap water(pH 6.4), and treated by 5mm each time for three minutes during the growing seasons(April to October 1985). Acid rain treatments were done three times per week to potted seedlings by spraying the solutions. The chemical properties of potting media were compared among three soil types as well as among the various pH levels. The results obtained in this study were as follows : 1. Exchangeable calcium and magnesium contents and base saturation of the soil decreased with decreasing pH levels of acid rain, and their decreasing rates were as follows : sandy soil was the highest, followed by mixed and nursery soils, However, exchangeable aluminum content rather increased as the pH levels decreased. 2. Available phosphate in the soil decreased as the pH levels of acid rain decreased. Its content increased in nursery soil, compared with those before acid gain treatment, Gut decreased in mined and sandy soils. 3. Soil sulfate and nitrate contents increased remarkably as the pH levels decreased, and the only significant difference in the sulfate was found among the pH levels. Soil sulfate content was the highest in nursery soil, followed by mixed and sandy soils.

• Applied Biological Chemistry
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• v.41 no.1
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• pp.6-12
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• 1998

To extract insoluble proteins and to improve functional properties of abolished proteins, a protease producing Aspergillus sp. MS-18 was isolated from soil. The enzyme was purified and its enzymological characteristics were investigated. It was found that production of protease reached to the maximum when the wheat brae medium containing, 3% arabinose, 0.5% polypepton, 0.1% $(NH_4)_2SO_4$ and 0.2% magnesium chloride was cultured for 3 days. Protease was purified 16.9 folds after ion exchange chromatography and gel filtration and the specific activity was 340.4 unit/mg. Purified enzyme was confirmed as a single band by the polyacrylamide gel electrophoresis. The molecular weight of protease was estimated to be 30,000. Crystalization form of purified protease was a stick shape with rounding edges. The optimum pH and temperature for the protease activity were 9.0 and $60^{\circ}C$, respectively. The enzyme was stable in pH 7.0-12.0 at $50^{\circ}C$. The activity of purified enzyme was inhibited by $Hg^{2+}$, $Cu^{2+}$, $Zn^{2+}$ and $Pb^{2+}$, whereas it was activited by $Na^+$, $Mg^{2+}$ and $Mn^{2+}$. The activity of the protease was inhibited by the treatment with ethylenediaminetetraacetic acid and phenylmethane sulfonyl fluoride. The result suggests that the purified enzyme is a serine protease with metal ion at active site. Km and Vmax of purified protease were $29.33\;{\mu}mole/L$ and $5.13\;{\mu}g/min$, respectively.

• Clinical and Experimental Pediatrics
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• v.45 no.3
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• pp.383-389
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• 2002

We experienced a case of partial DiGeorge syndrome in a $35^{＋5}$ week premature female infant presented with micrognathia, fish-shaped mouth, beaked nose, nasal regurgitation, obstructive sleep apnea, velopharyngeal insufficiency and late onset hypocalcemic seizures. The chromosome 22q11 microdeletion was found by the FISH method. The lab findings showed serum calcium level of 4.4 mg/dL, ionized calcium level of 0.49 mg/dL, phosphorous level of 7.5 mg/dL, magnesium level of 1.3 mg/dL and PTH-RIA level of <1 pq/mL. Initial treatment was done with 10% calcium gluconate infusion and magnesium sulfate followed by oral calcium gluconate and low phosphorousformula milk feeding. The serum calcium level was normalized in 6 days. Nasal regurgitation, desaturation with obstructive sleep apnea continued. T-cell functions & numbers(CD 3, CD 4, CD 8)were decreased but Ig G/A/M levels were normal. No visible signs of thymus shadow were seen in either chest X-ray & chest MRI. Electrocardiography and echocardiography showed normal heart. Kidney ultrasonographby showed right side mild hydronephrosis. Neurosonography was normal but EEG showed electrical partial seizure. Hearing assessment by BERA showed mild to moderate hearing impairment. Velopharyngoplasty is scheduled for further treatment. A brief review of literature was made.

• Journal of Korean Society of Forest Science
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• v.87 no.3
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• pp.341-346
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• 1998

The effects of CaO, $CaO+MgSO_4$, and $CaO+MgSO_4$+compound fertilizers(NPK) on soil chemical properties of acidified forest soils were studied in Quercus spp. and Pinus rigida stands in Mt. Namsan and Mt. Surak in urban areas, and Kwangnung in a mountain area. The soil samples were collected in November 1995 after every year fertilization from November 1991 through April 1995. The fertilizations affected soil chemical properties. Soil pH increased after fertilizations compared with control. However, the effect was different between the stand types and the areas. Organic matter and total nitrogen content were not changed, while exchangable cations such as calcium and magnesium increased after fertilizations. However, these ration concentrations after fertilizer treatments were lower in P. rigida than in Quercus spp. stands. These rations also showed increased leaching characteristics more in the urban area than in the mountain area.

• Analytical Science and Technology
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• v.13 no.2
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• pp.158-165
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• 2000

The purity of gypsum and quantitation of impurities of flue gas gypsum will not only play an important role in deciding of the optimal condition during a trial run of FGD (flue gas desulfurization), but also can be utilized in quality control of gypsum. The purity of gypsum can be determined from combined water, sulfur trioxide and calcium concentration. We found that the thermal analysis by TGA (thermogravimetric analysis) was the most accurate and convenient method to determine the purity of gypsum. This method will be done in a hour and the results were reproducible. On the other hand, the best way of the analysis of impurities in gypsum was fusion method using $LiBO_2$ as a fusion agent. We also determined the amount of $CO_2$ gas to analyze magnesium carbonate and calcium carbonate contents. The analyses of combined water by TGA, fusion method followed by ICP-AES (inductively coupled plasmaatomic emission spectroscopy) and determination of $CO_2$ amount can lead to more accurate and convenient method for gypsum analysis.

• Journal of the Mineralogical Society of Korea
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• v.30 no.4
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• pp.205-217
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• 2017

Mineral carbonation by indirect method has been studied by serpentinite as cation source. Through the carbonation of $CO_2$ and alkaline earth ions (calcium and magnesium) from serpentinite, the pure carbonates including $MgCO_3$ and $CaCO_3$ were synthesized. The extraction solvent used to extract magnesium (Mg) was ammonium sulfate ($(NH_4)_2SO_4$), and the investigated experimental factors were the concentration of $(NH_4)_2SO_4$, reaction temperature, and ratio of serpentinite to the extraction solvent. From this study, the Mg extraction efficiency of approximately 80 wt% was obtained under the conditions of 2 M $(NH_4)_2SO_4$, $300^{\circ}C$, and a ratio of 5 g of serpentinite/75 mL of extraction solvent. The Mg extraction efficiency was proportional to the concentration and reaction temperature. $NH_3$ produced from the Mg extraction of serpentinite was used as a pH swing agent for carbonation to increase the pH value. About 1.78 M of $NH_3$ as the form of $NH_4{^+}$ was recovered after Mg extraction from serpentinite. And, the main step in Mg extraction process of serpentinite was estimated by geochemical modeling.

• Microbiology and Biotechnology Letters
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• v.4 no.4
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• pp.131-137
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• 1976

Aspergillus niger S-1 was proved to be a good hesperidinase producer which have been selected for naringinase utilization. Enzyme of this strain had good characteristics and purified relative high degree with good recovery by ammonium sulfate or aceton treatment. Results obtained were summarized as follows (1) The enzyme was most active at 60$^{\circ}C$, when the reaction was performed in the pH 4.0 for 30min. Optimum pH for enzyme activity was 5.0 and activity was retained 78％ at pH value 3.5. (2) Hesperidinase activity retained 95％ of its full activity after treatment at 60$^{\circ}C$ for 30min at pH value 4.0., 70％ at 70$^{\circ}C$ and 65％ at 80$^{\circ}C$. Most stable pH of this enzyme was showed 5.0 after treatment for 24hr at 4$^{\circ}C$ (3) Only Magnesium ion activated enzyme reaction, while other metallic ions, Cu$\^$＋＋/, Mn$\^$＋＋/, Pb$\^$＋＋/, Mo$\^$＋＋/, Ag$\^$＋＋/, Hg$\^$＋＋/ inhibited. (4) Eleven fold purification with 35％ recovery was obtained in the case of 60％ aceton treatment and 10-fold purification with 5.6％ recovery was showed with 40％ aceton comparing to the crude extract Enzyme. (5) Crude enzyme precipitated with 0.4-0.6 saturated ammonium sulfate contained 13f6 of the original enzyme activity with 48-fold increase in specific activity and enzyme has been purified 25 fold with a yield 19％ by 0.6-5.8 saturation. (6) Hesperidinase formation was noticeably increased by addition of small amount of orange-peel extraction on the wheat bran medium.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.1
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• pp.1-10
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• 2012

The objective of this study was to investigate the sanitary and nutritional requirements for the industrialization of commercial kwamegi from Pacific herring Clupea pallasii (CK-PH). The proximate composition of CK-PH was 46.4-47.2% moisture, 24.7-25.6% crude protein, 23.6-25.2% crude lipid, and 2.5-2.9% ash, which differed significantly from that of commercial kwamegi from the Pacific saury Cololabis saira. According to the volatile basic nitrogen content, heavy metal content, and viable cell and coliform group counts, products K and F (prepared by a general process) maintained their freshness, whereas product T (treated with green tea extract) did not. Products K and F contained five types of biogenic amine: agmatine sulfate (2,596 and 2,067 mg/kg, respectively), putrescine dihydrochloride (8.5 and 8.0 mg/kg, respectively), cadaverine (3.7 and 3.9 mg/kg, respectively), histamine (17.0 and 12.4 mg/kg, respectively), and spermidine (8.7 and 8.0 mg/kg, respectively). Product T contained six amine types: tyramine (12.5 mg/kg), agmatine sulfate (2,723 mg/kg), putrescine dihydrochloride (29.4 mg/kg), cadaverine (321.6 mg/kg), histamine (45.3 mg/kg), and spermidine (13.6 mg/kg). The total amino acid content of product K (22.16/100g) was 5.8% lower than that of product F. The major amino acids of products K and F were aspartic acid, glutamic acid, leucine, and lysine. No difference was found in the fatty acid composition of products K and F. The major fatty acids in products K and F were 18:1n-9, 20:5n-3, and 22:6n-3. Based on the recommended daily dietary allowances for Koreans, the significant minerals in products K and F were calcium, phosphorus, and magnesium.