• Journal of Life Science
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• v.12 no.1
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• pp.55-60
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• 2002

The differentiation of skeletal muscle precursor cells in culture is marked by the transcriptional activation of muscle-specific genes and the morphological differentiation of myoblast into multinucleate myotube. In this study, we examined the effect of TSA (Trichostatin A) on WF-kB DNA binding activity and muscle cell fusion in the process of myogenesis. Under TSA treatment, C2C12 myoblast could not fuse to myotube and its NF-kB DNA binding activity was also blocked. To investigate whether these phenomenons were affected by TSA in direct or not, differentiation media (DM) used to differentiate cells without TSA was concentrated and added to C2C12 myoblast with TSA simultaneously. C2C12 myoblast was fused to myotube and NF-kB DNA binding activity was recovered. These results suggest that TSA affects on the differentiation of myoblast, perhaps through several factors, by inhibiting myoblst fusion and blocking NF-kB DNA binding activity.

• Korean Journal of Microbiology
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• v.35 no.4
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• pp.283-288
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• 1999

The effect of dissolved oxygen(DO) concentration on the growth of Pseudomonas aeruginosa and it's mutant M-10 was studied the growth kinetics and the possibility of waste treatment for reducing the amount of excess sludge. Different DO concentrations on the growth of wild type Pseudomonas aeruginosa affected to cellular yields, decreasing with increasing DO concentrations. Under these conditions, the maximum 14 folds decrease of cellular yield was achieved at 90 ppm DO levels by screened, being able to reduce their cellular yields under low DO concentration. The optimum mutation conditions were obtained by the treatment of NTG mutagen at 30${\circ}C$ for 1 hr. The growth characteristics of the selected mutant M-10 showed the same as the wild type growth kinetics. However, cellular yields are significantly decreased to 55% compared with those of wild type under DO concentrations increased. We, therefore, expect the application of the mutants to waste treatment for reducing excess sludge.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.2
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• pp.203-212
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• 2019

Disposal nonconformity of radioactive wastes refers to radioactive wastes that need to be treated, solidified and packaged during operation or decommissioning of NPPs, and are typically exemplified by particulate radioactive wastes with dispersion characteristics. These wastes include the dried powders of concentrated wastes generated in the process of operating NPPs, slurry and sludge, various powdered wastes generated in the decommissioning process (crushed concrete, decontamination sludge, etc.), and fine radioactive soil, which is not easy to decontaminate. As these particulate wastes must be packaged so that they become non-dispersive, they are solidified with solidification agents such as cement and polymer. If they are treated using existing solidification methods, however, the volume of the final wastes will increase. This drawback may increase the disposal cost and reduce the acceptability of disposal sites. Accordingly, to solve these problems, this study investigates the pelletization of particulate radioactive wastes in order to reduce final waste volume.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.2
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• pp.113-118
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• 2014

So many nationwide drinking water treatment plants are under much difficulties by new reinforced discharged effluent standards. Generally, the sludge at thickener should be retended for a long time during usual days. Sometime, the soluble manganese and chloroform may be formed under the anaerobic condition in the sludge thickener when the sludge retention time is longer with low turbidity. This phenomenon results in difficulties to keep regulatory level of the discharged effluent. It was necessary to improve the operation conditions and process itself in order to meet water quality standard recently reinforced. For an effort to overcome the problems, a sludge aeration was successfully implemented into the thickening process. Sludge aeration prevent particle oxidated Manganese eluting soluble de-oxidated Manganese, excrete formated Chloroform from effluent to air, and improve sludge settling through homogenized sludge particle. We aerated sludge at the conventional water treatment plant, measured Manganese and Chloroform of clarified water at upper sludge, and solid-fluid interface height of sludge in mass cylinder. As a result, contaminant's concentrations of the final effluent was much decreased : 41% of manganese, approximately 62% of chloroform and 35% of sludge volume, compared with non-aeration sludge.

• Applied Chemistry for Engineering
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• v.33 no.6
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• pp.581-587
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• 2022

The leather industry generates a large amount of hazardous leather waste of various types every year. Among them, shaving scrap is difficult to recycle because it contains chromium ions. Many studies in recent years have shown that shaving scraps can be processed into various types of valuable products, such as adsorbent, filler, and poultry feed. In this study, collagen peptides were extracted from shaving scraps and structurally modified to be developed as new materials with improved physicochemical properties. First, the chromium ions contained in the shaving scraps were removed using a sodium hydroxide solution, and purified through concentration and low-temperature crystallization. The purified collagen peptide was used to prepare the powder using a spray dryer. The extracted collagen peptides were structurally modified by introducing double bonds by reacting with methacrylic anhydride (MAA), and the product was confirmed by ¹H NMR spectroscopy. Next, a copolymer was prepared by redox polymerization of the modified collagen peptide (MCP) and 2-ethylhexyl acrylate (2-EHA). The structure of the copolymer was qualitatively confirmed by FT-IR. In conclusion, this study confirmed that collagen peptides can be extracted from shaving scrap and converted into new eco-friendly materials through certain treatments.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.11
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• pp.983-988
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• 2009

This study was performed to evaluate the toxicity and seek the control method of the wastewater in which nickel (Ni) was included into an industrial wastewater treatment plant. Nickel concentration of the wastewater, of which samples were taken every hour during 24hours, were various from 0.33 to 116.0 mg/L, with 24.0 mg/L of the average concentration. IC50 values against nitrosomonas and nitorbactor, a toxic level against bacteria which could inhibit 50% of nitrification bacteria in the wastewater, are 5.5 and 4.9 mg/L respectively. Nickel in this industrial wastewater can inhibit the 50% of nitrification bacteria even after diluting this wastewater 5 times. Also, this research, which reduced the nickel concentraion, forming nickel hydroxide compounds by increasing pH of the wastewater, shows that nickel concentraion can be obtained under 1.7 mg/L at pH 11 and 0.6 mg/L at pH 12. Consequently, the result of this study is that the nitrification efficiencies can be obtained from 83.8 to 99.4% with 97.6% of the average in the biological treatment after removing nickel in the wastewater by increasing the pH above 11~12, which is forming the nickel hydroxide compounds.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.146.2-147
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• 2003

콩 발효식품은 예로부터 단백질 식품원으로서 뿐만 아니라, 식생활에서 없어서는 안되는 매우 중요한 식품 중의 하나였다. 발효식품에 대한 연구가 부진하였던 과거에는 콩 발효식품은 하나의 식품군으로서의 중요성을 가질 뿐 큰 관심의 대상은 아니었다. 그러나 최근에는 많은 연구자들이 콩 발효시 생성되는 기능성 성분 및 생리활성 효과를 점차 밝혀냄으로서 주목을 받기 시작하였다. 따라서 본 실험에서도 콩 발효에 의한 생리활성 효과를 알아보기 위해 Ames법에 의한 항돌연변이원 효과를 실험하였다. 콩 발효는 국산콩을 이용하여 메주에서 분리한 Bacillus sp. 와 Aspergillus sp.를 복합 발효시켜 동결건조 후, 분쇄하여 실험에 사용하였다. 제조된 발효 콩 분말은 일반분석을 행하였으며, 70% 에탄올로 3회 추출하여 감압농축 후, hexane, chloroform ethyl acetate, butanol 및 aqueous로 분획하여 동결 건조시킨 후, S. typhimurium TA98 및 TA100 균주를 이용한 유전자 복귀 돌연변이 시험을 실시하였다. 그 결과, 70% 에탄을 추출물과 각각의 분획물 자체의 돌연변이원성은 없었다. 또한 항돌연변이원 실험에서는 발암물질로서 직접 돌연변이원인 4NQO와 MNNG, 간접 돌연변이원인 Trp-P-1을 이용하였다. 특히 이들 발암물질 중 MNNG(0.4 $\mu\textrm{g}$/plate)의 경우 TA100 균주에서 ehtyl acetate 분획물에서 다른 분획물보다 높은 86.6%의 억제 효과를 나타내었으며, 대부분의 분획물에서도 70%이상의 억제효과를 나타내었다. 또한 각 분획물에서 농도 의존적으로 억제효과 역시 높았으며, 분획물에 따라 서로 다른 억제효과를 나타내었다.아 저장할 때 대비 저온저장고에서는 111일 동안에 11.7%의 중량감모가 발생하였으나, 신기술투입 저온저장고에서는 5.6%의 중량감모만이 발생하여 약 50%의 중량감모를 줄일 수 있었으며, 배의 색깔이나 경도도 대비구 보다 우수하였다. 4. 배를 비닐로 포장하여 대비 저온저장고에 저장한 경우와 비닐로 포장하지 않고 신기술투입 저온저장고에 저장한 경우를 비교할 때 11월~다음해 1월 까지는 중량감모, 과피색깔 및 경도에 큰 차이가 없었으나, 2월부터는 비닐로 포장하여 대비 저온저장고에 저장한 배의 품질변화가 급격히 증가되어 중량감모, 과피색깔 및 경도가 신기술 투입시 보다 급속하게 나빠졌다.를 저장 25일 경과시까지 유지하였다. 수확 시 높은 품온을 갖고 있는 과일을 산지에서 예냉 처리를 한 후 저온 냉장차를 이용하여 유통한다면 관행 유통 구조보다 고품질의 포도를 유통시킬 수 있는 것으로 사료되며 앞으로는 완숙된 고 당도(12.0~15.0Bx)$^{\circ}$ 포도를 수확 한 즉시 예냉 처리하고 저온 유통한다면 보다 신선한 과일을 소비자에게 전달 할 수 있을 것이다.갈변물질이 생성되었다. 이와 같은 결과로 볼 때, BAAG의 처리는 BAAC의 경우보다 가격은 저렴하면서도 항균력은 우수한 천연 항균복합제재로써 농산물 식품원료에 적용하여 선도유지 기간을 연장할 수 있는 효과를 기대할 수 있었다. 과일 등의 포장제로서 이용할 가능성을 확인하였다.로 [-wh] 겹의문사는 복수 의미를 지닐 수 없 다. 그러면 단수 의미는 어떻게 생성되는가\ulcorner 본 논문에서는 표면적 형태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(minimal $X^{0}$

• Analytical Science and Technology
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• v.6 no.3
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• pp.283-288
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• 1993

The solvent extraction and clean up processes for the gas chromatographic determination of muarimol pesticide residues in apples were investigated and examined the changes of residual concentration with the passage of time. The extracted pesticide with methanol were partitioned with dichloromethane after adding sodium chloride solution. The separated solutions were concentrated and transfered to the alumina column for clean up, and eluated with 1-chlorobutane : methanol solution. As a results their recovering for 0.200 and 1.00ppm muarimol spiked on apples have shown 79~95%. Residual amounts of nuarimol in apple was 0.0830ppm when the fungicide was treated eight times until 3 days before its harvest. It seems to be safely used when nuarimol is treated six times until 7 days before harvest of apple.

• Journal of Environmental Impact Assessment
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• v.21 no.5
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• pp.707-713
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• 2012

There are a lot of parameters affecting microbial acclimation/cultivation characteristics such as dynamic conditions, F/M ratio and substrate affinity. From the process control point of view, the effect of high salinity on the removal efficiencies of BOD and SS have been documented by few researchers. In this research, lab-scale CAS(Conventional Activated Sludge) process and modified $A_2O$(Anaerobic/Anoxic/Oxic) process were operated and monitored to evaluate the characteristics of microbial acclimation and cultivation under high salinity wastewater during the period of three weeks. As a result of acute microbial activity test(6hr) at various $Cl^-$ concentration, the appropriate $Cl^-$ concentration for microbial growth and acclimation ranged under 3,100 mg/l. As a result of acclimation/cultivation test, the trend of COD removal efficiency reduced gradually as time elapsed. It is considered that $NH_4$-N removal phenomenon of the conventional pollutants removal mechanisms gave little effect to the microbial acclimation/cultivation under high salinity wastewater.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.5
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• pp.407-412
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• 2014

A new apparatus for seawater desalination, based on the principle of gas hydrates, is suggested. The equipment continuously produces and pelletizes gas hydrates by a squeezing operation in a dual cylinder unit, which is able to extract pure hydrate pellets from the seawater-containing reactor. Desalination efficiency for each dissolved ion from seawater samples was tested by inductively coupled plasma atomic emission spectroscopy (ICP-AES) and ion chromatography (IC) analysis. This study demonstrates that the suggested method and the stated apparatus may solve the difficulty of separating hydrate crystals from concentrated brine solutions, and therefore may be applied to improve the efficiency of existing desalination processes.