• Korean Journal of Environmental Agriculture
• /
• v.23 no.2
• /
• pp.92-98
• /
• 2004

The adsorption and desorption of Pb, Cd, Co, Zn, Cr, Co, Ni, and Mo on the waste Undaria sp. were studied. Except for Pb. the mono adsorption rate for all heavy metals were lower than that of the heavy metals mixed. However, the adsorption capacity of the heavy metals by 1g of biosorption, in mixed heavy metals increased According to FT-IR analysis of the biosorbent after heavy metal biosorption, the replacement of the functional group by the heavy metals ions could be confirmed and the inverted peaks became larger after heavy metals adsorption. The adsorption equilibrium of heavy metals was reached in about 1 hour. The equilibrium parameters were determined based on Langmuir and Freundlich isotherms. The affinity of metals on the biosorbent decreased in the following order: Pb>Cu>Cr>Cd>Co. The desorption rate decreased in the following sequence: NTA>$H_2SO_4$>HCl>EDTA. The desorption rate of heavy metals by NTA increased with increase in the concentration from 0.1 to 0.3% but the desorption rate became constant beyond 0.3%. Therefore, it represented that desorption rate of heavy metals was suitable under optimized condition ($30^{\circ}C$, pH 2 and 0.3% NTA solution) and was fast with 80% or more the uptake occurring within 10 min of contact time.

• Economic and Environmental Geology
• /
• v.19 no.2
• /
• pp.109-122
• /
• 1986

Mn-Pb-Zn-Ag deposits of the Janggun mine are hosted in the Cambro-Ordovician Janggun limestone mostly along the contacts of the Jurassic Chunyang granite. The deposits are represented by several ore pipes and steeply dipping lenticular bodies consisting of lower Pb-Zn-Ag sulfide ores and upper manganese carbonate and oxide ores. The former consists mainly of arsenic, antimony, silver, manganese, and tin-bearing sulfides, whereas the latter are characterized by hypogene rhodochrosite, and superficial manganese oxides including todorokite, nsutite, pyrolusite, cryptomelane, birnesite and janggunite. Origin of the upper manganese ore deposits has been a controversial subject among geologists for this mine: hydrothermal metasomatic vs. syngenetic sedimentary origin. Syngenetic advocators have proposed a new sedimentary rock, rhodochrostone, which is composed mainly of rhodochrosite in mineralogy. In the present study, carbon, oxygen and sulfur isotopic compositions were analayzed obtaining results as follows: Rhodochrosite minerals, (Mn, Ca, Mg, Fe) $CO_3$, from hydrothermal veins, massive sulfide ores and replacement ores in dolomitic limestone range in isotopic value from -4.2 to -6.3‰ in ${\delta}^{13}C$(PDB) and +7.6 to +12.9‰ in ${\delta}^{18}O$(SMOW) with a mean value of -5.3‰ in ${\delta}^{13}C$ and +10.7‰ in ${\delta}^{18}O$. The rhodochrosite bearing limestone and dolomitic limestone show average isotopic values of -1.5‰ in ${\delta}^{13}C$ and +17.5‰ in ${\delta}^{18}O$, which differ from those of the rhodochrosite mentioned above. This implies that the carbon and oxygen in ore fluids and host limestone were not derived from an identical source. ${\delta}^{34}S$ values of sulfide minerals exhibit a narrow range, +2.0 to +5.0‰ and isotopic temperature appeared to be about $288{\sim}343^{\circ}C$. Calculated initial isotopic values of rhodochrosite minerals, ${\delta}^{18}O_{H_2O}=+6.6$ to +10.6‰ and ${\delta}^{13}C_{CO_2}=-4.0$ to -5.1 ‰, strongly suggest that carbonate waters should be deep seated in origin. Isotopic data of manganese oxide ores derived from hypogene rhodochrosites suggest that the oxygen of the limestone host rock rather than those of meteoric waters contribute to form manganese oxide ores above the water table.

• Korean Journal of Microbiology
• /
• v.51 no.4
• /
• pp.374-381
• /
• 2015

Occurrences of coastal dredged materials are ever increasing due to port construction, navigational course maintenance and dredging of polluted coastal sediments. Ocean dumping of the coastal dredged materials has become virtually prohibited as London Treaty will be enacted as of the year 2012. It will be necessary to treat and recycle the dredged materials that may carry organic pollutants and heavy metals in a reasonable and effective process: collection of the dredged materials, liquid and solid separation, and treatment of organic compounds and heavy metals. In this study we have developed a continuous bioreactor system that can treat a mixture of silt and particulate organic matter using a microbial consortium (BM-S-1). The steady-state operation conditions were: pH (7.4-7.5), temperature ($16^{\circ}C$), DO (7.5-7.9), and salt concentration (3.4-3.7%). The treatment efficiencies of SCOD, T-N and T-P of the mixture were 95-96%, 92-99%, and 79-97%. The system was also effective in removal of heavy metals such as Zn, Ni, and Cr. Levels of MLSS during three months operation period were 11,000-19,000 mg/L. Interestingly, there was little sludge generated during this period of operation. The augmented microbial consortium seemed to be quite active in the removal of the organic component (30%) present in the dredged material in association with indigenous bacteria. The dominant phyla in the treatment processes were Proteobacteria and Bacteroidetes while dominant genii were Marinobacterium, Flaviramulus, Formosa, Alteromonadaceae_uc, Flavobacteriaceae_uc. These results will contribute to a development of a successful bioremediation technology for various coastal and river sediments with a high content of organic matter, inorganic nutrients and heavy metals, leading to a successful reuse of the polluted dredged sediments.

• Economic and Environmental Geology
• /
• v.29 no.1
• /
• pp.65-75
• /
• 1996

Sulfate reduction and the precipitation of metal sulfides may have great potential to improve water quality of mine effluents in wetland treatment systems. Laboratory experiments using sulfate reducing bacteria (SRB) and limestone to treat effluents from the abandoned Dalsung tungsten-copper mine show that encouraging results, that have been attributed to sulfate reduction. Fe, Al, Cd, Cu and Zn are reduced to below detection limits with $99{\sim}100%$ metal removal rates, Mn is reduced by at least 90% to below 8.0 mg/l, and the pH is raised from 5.12 to 7.60 after 53 days of experiments. In the staged design, laboratory experiments are initiated to determine what would be reasonable substrate materials for remediation of the mine effluents. A substrate mixture containing 70% oak compost and 30% mushroom compost maintains $0.03{\sim}0.04mM$ of lactate, which provides good condition for the SRB granule. A downflow SRB wetland system is proposed as follows : 1) The lower part of the treatment system consists with a 25 cm thick layer of high quality (above 95% of $CaCO_3$) of limestone; 2) The geotextile (geonet) is recommended to be spread on the limestone bed to prevent clogging the limestones with the substrates; 3) The mixture of substrates with 70% oak and 30% spent mushroom composts, and SRB granules overlain on top of the geonet with 25 cm height. The sizes of the passive treatment systems are calculated according to metal loading and permeability criteria : 1) $220m^3$ ($15{\times}15{\times}1m$) for -1 level effluents; 2) $28m^3$ ($5.3{\times}5.3{\times}1m$) for -2 level; and 3) $2700m^3$ ($52{\times}52{\times}1m$) for the -3 level. The -3 level system needs to be broken down into 5 to 15 cells.

• Proceedings of the Korea Association of Crystal Growth Conference
• /
• 1996.06b
• /
• pp.219-222
• /
• 1996

수열법은 밀폐용기중에서 10$0^{\circ}C$이상의 가열, 가압된 수용액이 반응에 관여하는 것으로써, 수정, CaCO3, AlPO4, GaPO4 등과 같은 단결정의 육성 뿐만 아니라 균일분산계로부터 균일한 결정성의 미립자 합성에도 폭넓게 이용되고 있다. 세라믹분말의 합성에 있어서, 이 방법은 특히 형상, 입자크기의 제어가 용이할 뿐만 아니라 고상법, 졸-겔법, 공침법에서와 같은 열처리, 분쇄과정이 필요없기 때문에 고순도의 초미립자를 얻을 수 있는 장점이 있다. 근년 미국, 일본에서는 수열법을 이용한 유전, 압전체 등 세라믹분말의 일부가 공업적인 규모로 대량 생산되고 있다. 그러나 이에 대한 국내 기술은 아직 초기단계에 이르고 있는 실정이다. 따라서 본 연구실에서는 수열법에 의한 단결정 육성 (예; 자수정, CaCO3, AlPO4, GaPO4, KTP, Emerald 등), 박막제조 (예; GaP, PbTiO3, BaTiO3 등), 정제 (고령토, 장석, 도석 등), 원석처리 (진주, 인공 emerald, 비취 등) 그리고 각종 세라믹분말의 합성 등과 같은 다양한 기반기술의 축적과 동시에 공업화에 대응한 수열장치를 위하여 반응용기의 대형화, 엄밀한 밀폐방식, 실용적인 수열조건 등을 개발해 오고 있다. 본 발표에서는 현재까지의 연구개발 내용 중에서 결정성 미립자에 관련한 세라믹분말의 합성에 대한 일부의 결과들을 보고한다. 일반적으로 수열장치는 전기로, 반응용기, 온도 및 압력제어계 등을 기본으로 하고 있으며 시판용의 대부분이 교반기가 부착된 수직형 (vertical type)이다. 이와 같은 방식에 있어서는 엄밀한 밀폐가 곤란, 반응온도의 한계성 (25$0^{\circ}C$ 이하), 증진율의 한계성 (소량생산) 등과 같은 점이 있기 때문에 본 연구실에서는 개폐식 전기로내에 엄밀한 밀폐가 가능한 수평식(horizontal type)의 반응용기를 채택한 뒤 이를 회전 또는 시이소(seesaw)식으로 움직일 수 있도록 하여 연속공정화, 온도구배의 자율조절 그리고 보다 저온에서도 인위적인 이온의 확산을 효율적으로 유도할 수 있도록 하였다. 이와 같은 방식은 기존의 방식과 비교하여 반응용기 내에 응집현상과 미반응물이 존재하지 않으며 또한 단분산으로 결정성 미립자를 대량적으로 얻을 수 있는 장점이 있었다. 다음은 이상과 같이 본 연구실에서 자체 개발한 수열장치를 이용하여 PbTiO3, (Pb,La)TiO3Mn, BaTiO3, ZnSiO4:Mn, CaWO4 등과 같은 세라믹분말에 대한 합성 실험의 결과이다. 압전성, 초전성이 우수한 PbTiO3 및 (Pb,La)TiO3:Mn 분말의 수열합성은 PbO, TiO2, La2O3 등의 분말을 출발원료로 하여 합성도도 25$0^{\circ}C$부근의 알카리성 용액중에서 결정성 PbTiO3 및 (Pb,La)TiO3:Mn 미립자를 단상으로 얻었으며 입자의 형상 및 크기는 합성온도와 수열용매의 종류에 의존하였다. 유전체로서 폭넓게 응용되고 있는 BaTiO3 분말은 Ba(OH)2.8H2O, TiO2와 같은 최적의 출발원료를 선택함으로써 15$0^{\circ}C$ 부근의 저온영역에서도 용이하게 합성할 수 있었다. 특히 본 연구에서는 수용성인 Ba(OH)2.8H2O를 사용함으로써 host-guest적인 반응을 유도시키는데 있어 물의 가장 실용적이고 효과적인 수열용매임도 알았다. ZnSiO4:Mn, CaWO4, MgWO4와 같은 형광체 분말은 공업적으로 고상반응 또는 습식법에 의해 얻어지고 있으나 이들 방법에 있어서는 분쇄공정으로 인한 형광특성의 저하와 같은 문제점이 있다. 따라서 본 연구에서는 수열법을 이용하여 이들 화합물의 합성을 시도하였으며 그 결과 합성온도 30$0^{\circ}C$ 부근의 알칼리성 용액중에서 수열적으로 얻어짐을 알았다. 여기서의 합성분말을 이용하여 실제 조명램프로 제조한 결과 녹색, 청색 발광용 형광체로서 우수한 형광특성을 나타내었다. 천연에서 소량 산출되고 있는 고가의 (Li,Al)MnO2(OH)2:Co 분말은 도자기의 전사지용 청색안료로써 이용되고 있다. 본 연구실에서는 LiOH.H2O, Al(OH)3, MnO2 등의 분말을 출발원료로 하고 24$0^{\circ}C$ 온도 부근 그리고 물을 수열용매로 하여 천연산에 필적하는 (Li,Al)MnO2(OH)2:Co 분말을 인공적으로 합성하였다.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.46 no.6
• /
• pp.453-458
• /
• 2001

The Rural Development Administration (RDA) of Korea now operates a system called Rice Variety Selection Tests (RVST), which are now being implemented in eight Agricultural Research and Extension Services located in eight province RVST's objective is to provide accurate yield estimates and to select well-adapted varieties to each province. Systematic evaluation of entries included in RVST is a highly important task to select the best-adapted varieties to specific location and to observe the performance of entries across a wide range of test sites within a region. The rice yield data in RVST for ordinary transplanting in Kangwon province during 1997-2000 were analyzed. The experiments were carried out in three replications of a random complete block design with eleven entries across five locations. Additive Main effects and Multiplicative Interaction (AMMI) model was employed to examine the interaction between genotype and environment (G$\times$E) in the biplot form. It was found that genotype variability was as high as 66％, followed by G$\times$E interaction variability, 21％, and variability by environment, 13％. G$\times$E interaction was partitioned into two significant (P＜0.05) principal components. Pattern analysis was used for interpretation on G$\times$E interaction and adaptibility. Major determinants among the meteorological factors on G$\times$E matrix were canopy minimum temperature, minimum relative humidity, sunshine hours, precipitation and mean cloud amount. Odaebyeo, Obongbyeo and Jinbubyeo were relatively stable varieties in all the regions. Furthermore, the most adapted varieties in each region, in terms of productivity, were evaluated.

• Journal of Life Science
• /
• v.15 no.6 s.73
• /
• pp.987-993
• /
• 2005

A bacterium, producing a fibrinolytic enzyme, was screened from a decaying rice plant. The bacterium was identified as Bacillus subtilis by morphological, biochemical, and physiological properties and named Bacillus subtilis BK-17. The fibrinolytic enzyme (BK) was purified from supernatant of Bacillus subtilis BK-17 culture broth. The molecular weight was 31 kDa as determined by SDS-PAGE. The effect of temperature, pH, and plasminogen on the activity of the bacillokinase (BK) was analysed and the activity was compared with urokinase. The optimal temperature and pH were $50^{circ}C$ and pH 7, pH 8, respectively. The BK activity was inhibited to $45\%$, $35\%$, and $23\%$ with 1mM EDTA, $Zn^{2+}$, and $Ca^{2+}$, respectively. However, $Mg^{2+}$, $Mn^{2+}$, and $Co^{2+}$ ions did not have any significant effect on the enzyme activity The BK showed the artivity in the both plates, plasminogen-free fibrin plate and plasminogen-rich fibrin plate. The result indicates that the BK can directly act the fibrin. In comparison of fibrinolytic activity with urokinase on the fibrin plate, the BK shows about 20 folds higher activity than that of the urokinase.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.8
• /
• pp.1271-1283
• /
• 2007

A fibrinolytic protease (PoFE) was purified from the cultured mycelia of the edible oyster mushroom Pleurotus ostreatus, using a combination of various chromatographies. The purification protocol resulted in an 876-fold purification of the enzyme, with a final yield of 6.5%. The apparent molecular mass of the purified enzyme was estimated to be 32 kDa by SDS-PAGE, fibrin-zymography, and size exclusion using FPLC. The optimal reaction pH value and temperature were pH 6.5 and $35^{\circ}C$, respectively. PoFE effectively hydrolyzed fibrinogen, preferentially digesting the $A{\alpha}$-chain and the $B{\beta}$-chain over the ${\gamma}$-chain. Enzyme activity was enhanced by the addition of $Ca^{2+},\;Zn^{2+},\;and\;Mg^{2+}$ ions. Furthermore, PoFE activity was potently inhibited by EDTA, and it was found to exhibit a higher specificity for the chromogenic substrate S-2586 for chymotrypsin, indicating that the enzyme is a chymotrypsin-like metalloprotease. The first 19 amino acid residues of the N-terminal sequence were ALRKGGAAALNIYSVGFTS, which is extremely similar to the metalloprotease purified from the fruiting body of P. ostreatus. In addition, we cloned the PoFE protein, encoding gene, and its nucleotide sequence was determined. The cDNA of cloned PoFE is 867 nucleotides long and consists of an open reading frame encoding 288 amino acid residues. Its cDNA showed a high degree of homology with PoMEP from P. ostreatus fruiting body. The mycelia of P. ostreatus may thus represent a potential source of new therapeutic agents to treat thrombosis.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.26 no.5
• /
• pp.409-415
• /
• 1993

For the use of sea mustard in snack food as the supplement of minerals and nutrients, three types of product like sweet jelly, jam and candy were prepared adding fresh sea mustard homogenates, dried sea mustard powder and sea mustard extract, respectively. That were prepared by four different ways, cold water extract, hot water extract, $1\%$ NaOH extract and $95\%$ ethanol extract. The extract contains plenty of particulary iodine and calcium in hot water extract and other nutrients. Judging by sensory evaluation, color, flavor and taste of jam, sweet jelly and candy added with sea mustard, products were satisfactory to attractive snack food for children and these could be useful as the source of minerals and nutrients.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.36 no.4
• /
• pp.412-421
• /
• 2012

The yerba mate that grows in the subtropical forests of South America is an evergreen tree within the Aquifoliaceae family. The yerba mate (Ilex paraguariensis) tea is habitually used as a drink in Argentina, Paraguay, Uruguay, and Southern Brazil. A wild mate tree needs about 25 years to fully grow to 15 a height of meters; however, they only grow to a height of 3-5 meters when cultivated. The leaves are 7-11 cm long and 3-5cm wide with a serrated margin. Yerba mate tea-based beverages are made from the leaves and stems of the mate tree. It is known that they contain a rich content of antioxidants and polyphenol, vitamins, amino acids, minerals and colorants. Dyeing properties of a mate plant in the silk, wool, linen and cotton fabrics were investigated. Constituents of colorant of mate tea are chlorophyll and carotinoid; in addition, it has more minerals such as (Fe, Ca, Mn, Mg, Na, K, Zn, and Cu) than green tea. Mate tea colorants showed good affinity to silk and wool fabrics. It was found that the optimum condition for dyeing was 30 minutes for dyeing time, 7 for pH of dyebath, and at a dyeing temperature of $80^{\circ}C$. The maximum absorbance wavelength (${\lambda}_{max}$) of silk and wool fabrics dyed with mate tea were at 420-440nm; however, that of linen and cotton fabrics were at 400nm. K/S values of fabrics dyed under optimum conditions were 1.979 for silk fabrics, 1.541 for wool fabrics, 0.551 for linens and 0.465 for cotton fabrics. Munsell hue values of dyed fabrics measured 3.1Y-6.4GY for silk, 1.4Y-8.3Y for wool, 5.5Y-3.7GY for linen, and 5.3Y-1.3GY for cotton. All dyed fabrics showed hues in-between greenish yellow and greenyellow. Colorfastness to rubbing, perspiration and dry-cleaning of dyed fabrics with mate tea were very good; however, the grades of colorfastness to washing of dyed linen and cotton fabrics were poor, and colorfastness to light were poor.