• Journal of Microbiology and Biotechnology
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• 제25권11호
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• pp.1773-1781
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• 2015

Environmental security is one of the major concerns for the safety of living organisms from a number of harmful pollutants in the atmosphere. Different initiatives, legislative actions, as well as scientific and social concerns have been discussed and adopted to control and regulate the threats of environmental pollution, but it still remains a worldwide challenge. Therefore, there is a need for developing certain sensitive, rapid, and selective techniques that can detect and screen the pollutants for effective bioremediation processes. In this perspective, isolated enzymes or biological systems producing enzymes, as whole cells or in immobilized state, can be used as a source for detection, quantification, and degradation or transformation of pollutants to non-polluting compounds to restore the ecological balance. Biosensors are ideal for the detection and measurement of environmental pollution in a reliable, specific, and sensitive way. In this review, the current status of different types of microbial biosensors and mechanisms of detection of various environmental toxicants are discussed.

• 대한전기학회논문지:시스템및제어부문D
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• 제54권3호
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• pp.166-173
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• 2005

Preserving image features, edges and details in the process of impulsive noise filtering is an important problem. To avoid image blurring, only corrupted pixels must be filtered. In this paper, we propose an effective impulse noise detection method using Self-Organizing Neural Network(SONN) which applies median filter selectively for removing random-valued impulse noises while preserving image features, edges and details. Using a $3\times3$ window, we obtain useful local features with which impulse noise patterns are classified. SONN is trained with sample image patterns and each pixel pattern is classified by its local information in the image. The results of the experiments with various images which are the noise range of $5-15\%$ show that our method performs better than other methods which use multiple threshold values for impulse noise detection.

• 대한화학회지
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• 제67권6호
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• pp.415-419
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• 2023

In this study, we report the one-pot synthesis of reduced graphene oxide (rGO) containing platinum nanoparticles with catalytic activity to break down hydrogen peroxide as a peroxidase-mimicking catalyst. A single reducing agent was used to reduce graphene oxide and a platinum precursor at a moderately low temperature of 70℃. The rGO was homogeneously decorated with platinum nanoparticles. The catalytic activity of Pt-rGO was investigated for the oxidation of 3,3',5,5'- tetramethylbenzidine (TMB), a peroxidase substrate, in the presence of hydrogen peroxide. The Pt-rGO coupled with glucose oxidase was also able to detect glucose at millimolar concentrations (up to 1 mM). Our results show that the Pt-rGO composite is a promising catalyst for the detection of hydrogen peroxide. This method was also applied for the detection of glucose.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.403-404
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• 2009

• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1871-1874
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• 2013

• 대한화학회지
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• 제26권6호
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• pp.427-429
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• 1982

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 춘계총회,특별강연,심포지움,연구발표회
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• pp.74.2-74.2
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• 2000

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 추계총회,초청강연,특별강연,연구발표회
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• pp.155.2-155
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• 2000

• 한국식품저장유통학회지
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• 제16권6호
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• pp.965-970
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• 2009

유통중인 계란의병원성균 오염상태를 시판되는 multiplex polymerase chain reaction (mPCR) kit로 검사한 결과, 총 90개의 검사시료 가운데 한 가지 이상의 미생물이 검출된 계란시료는 30개로, 검사시료의 미생물 오염도는 약 33.3% 수준이었다. 미생물별 검출 빈도는 B. cereus가 17개 시료(18.9%)에서 검출되어 가장 높은 빈도를 보였으며 Y. enterocolitica는 16개(17.8%), L. monocytogenes 15개(16.7%), St. aureus 12개(13.3%), E. coli O157:H7 4개(4.4%)의 검출빈도를 보였다. 한편, 선택배지를 이용한 viable cell count 방법에서는 27개의 시료에서 미생물이 검출되어 검사시료의 미생물 오염도는 약 30.0% 수준이였으며, 미생물별 검출 빈도는 B. cereus가 17개 시료(18.9%)에서 14개(15.6%) 시료로, Y. enterocolitica는 16개(17.8%)에서 12개(13.3%)로, L. monocytogenes는 15개(16.7%)에서 13개(14.4%)로, St. aureus는 12개(13.3%)에서 10개(11.1%)로 감소하였으며, E. coli O157:H7은 두 가지 검출방법간의 차이가 나타나지 않았다. 검출 대상 미생물 9종 가운데 Campylobacter jejuni, Vibrio parahaemolyticus, Salmonella spp., 및 Shigella spp.는 두 방법 모두에서 검출되지 않았다. 이상의 결과에서 살펴본 바와 같이 PCR을 이용한 병원성 미생물의 검출 방법은 viable cell count 방법보다 감도가 높음을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제27권9호
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• pp.1315-1322
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• 2006

The following study describes the gas chromatography-mass spectrometry (GC-MS) based screening and confirmation analysis of urinary androgenic steroids. Four commercially available solid-phase extraction (SPE) cartridges, Serdolit PAD-1, Sep-pak $C_{18}$, amino-propyl, and Oasis HLB, and three different extractive organic solvents, diethyl ether, methyl tert-butyl ether (MTBE), and n-pentane, were tested for sample preparation. Overall, Oasis HLB combined with MTBE extraction provided the highest recoveries in 39 of 46 total androgenic steroids examined and it showed a good extraction yield (>82.1%) for polar steroids, such as metabolites of fluoxymesterone, oxandrolone, and stanozolol, which gave a poor recovery in both n-pentane (9.2-64.3%) and diethyl ether (22.2-73.6%) extractions. All SPE sorbents tested showed potential, because they were efficient in extraction for most or selective steroids. When applied to positive urine samples based on the results obtained, the present method allowed selective and sensitive analysis for detection of urinary androgenic steroids. The experiments showed that the high-resolution MS method is clearly more efficient than the low-resolution MS technique for the detection of many urinary steroids. However, comprehensive sample clean-up procedures also might be needed especially in confirmation analysis to increase detectability.