• Mycobiology
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• v.31 no.4
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• pp.226-228
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• 2003

The multiple correlation coefficient between the values determined by dry weight and those determined by fluorometer was observed with r=0.96 and the standard error of calibration was 0.034. Using the best calibration data, in order to reconfirm the reliability of the fluorometer results in comparison with those obtained by dry weight on the cell concentration, fedbatch cultures were carried out. The results obtained by fluorometer measurements were in good agreement with those obtained by dry weight. The on-line monitoring of cell concentration by the fermentor system linked to a computer equipped with fluorometer was successfully carried out.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1-3
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• 2003

In this study, spectroradiometer data were coupled with fluorometer data to find out the best suited bands ratio to monitor the chlorophyll a concentration for inland water. Remote sensing reflectance measurements were used to evaluate the performance of several default ocean color chlorophyll algorithms for SeaWiFS data. This study shows that the chlorophyll a concentration from fluorometer and reflectance from spectroradiometer lies in exploiting the signal provided by the chlorophyll a red absorption peak near 670nm. Two-band ratio based on a ratio of reflectance 670 and 700nm provided a good correlation for a linear model, compare with blue-green two band ratio.

• Journal of Environmental Health Sciences
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• v.34 no.6
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• pp.423-432
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• 2008

In this study, we investigated the possibility of auto control and the proper operating factors in the BNR(Biological Nutrient Removal) process using an NADH(Reduced Nicotinamide Adenine Dinucleotide) fluorometer, which characterized the emitted fluorescence when activated by flashes of UV light at 460 nm. In terms of finding adequate operating parameters, results indicted that nitrification efficiency decreased in the controlled DO while denitrification efficiency decreased in the controlled pH. The above results indicated that controlled operating condition after combination with NADH, DO and pH was resonable. Result obtained from the correlation between NADH and pH showed that variation trend of influent loading was similar to those of NADH and pH, and also the variation cycle was repeated on a daily basis. Consequently, this result showed the increase of BOD loading caused the nitrification efficiency to decrease because air-flow, required for nitrification, was reduced, and so the NADH value was increased. From these results, it is possible to use NADH flourimetry to assess the variation of organic load and nitrification efficiency in the case of small change in influent pH such as in sewage and also to handle and operate the load variation in the auto control system using the NADH fluorometer.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.110-111
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• 2000

대기중 가스상 $H_2O_2$(Hydrogen Peroxide)는 액상 화학반응과 기상 라디칼반응사이에 연결고리의 역할을 할 뿐만 아니라, 대기중의 $SO_2$를 $H_2SO_4$로 산화시키는 산화제로서 구름, 안개, 이슬 및 빗물의 산화에 중요한 역할을 담당한다. 또한 가스상 $H_2O_2$는 연쇄종결자와 $HO_2$.(hydroperoxyl radical)농도의 지표로서 광화학 스모그에 있어 중요한 화학종이기도 하다. $H_2O_2$농도의 증가는 결국 대기의 산화율 및 속도를 증가시키고 대류권내의 액상중에서 $H_2SO_4$ 생성을 가속화시킨다는 것은 이미 잘 알려져 있는 사실이다. (중략)

• Journal of the Korean Chemical Society
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• v.56 no.5
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• pp.577-582
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• 2012

Quinine quantitative analysis, photo-bleaching, fluorescence quenching, and urine analysis have been performed by means of a UV-LED fluorometer, which can be easily built and used in a high-school laboratory. The quinine detection range is estimated to be 0.05-80 ppm, enough for many classroom luminescence experiments. The quinine content in commercial tonic water is determined from the calibration curve, and UV photo-bleaching of this anti-malarial drug is demonstrated with clear wavelength dependence. Halide quenching of quinine fluorescence is also observed and the increase in quenching efficiency in the order of $Cl^-$, $Br^-$, and $I^-$ is evident. Urine analyses for the student volunteers have been carried out and the results clearly reveal excretion of the ingested quinine. The student participants are exuberant throughout the course of this study and sense the practices resourceful.

• KSBB Journal
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• v.21 no.5
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• pp.341-346
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• 2006

This study was carried out to establish the optimum condition for cell disruption with a sonificator in the detection of the gram negative bacteria, E. coli for the purpose of developing automatic fluorometer. The efficiency of sonification on the E. coli disruption was greatly dependent on the diameter of sonificator probe tip. The larger sonificator probe diameter showed greater disruption effect. Sonificator probe of 13 mm diameter was the most efficient one for E. coli when sonificated for 20 seconds. The efficiency of the E. coli disruption differed greatly according to the depth of sonificator probe tip sank in the sample solution. The shorter the distance between probe tip end and the bottom of the container, the higher the disruption efficiency. The detection limit of E. coli was $5{\times}10^5CFU/m{\ell}$ when sample was sonificated for 20 seconds with a sonificator probe of 13 mm diameter.

• KSBB Journal
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• v.21 no.5
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• pp.347-352
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• 2006

This study was carried out to establish the optimum condition for cell disruption with a sonificator in the detection of the gram positive bacteria, Bacillus globigii and Streptococcus epidermidis for the purpose of developing automatic fluorometer. The efficiency of sonificator on the Bacillus globigii and Streptococcus epidermidis disruption differed greatly according to the diameter of sonificator probe tip. The larger sonificator probe diameter showed greater disruption. Bacillus globigii was more disruptive than Streptococcus epidermidis. Sonificator probe of the 13 mm diameter was the most efficient one when sample was sonificated for 20 seconds. The detection limits of Bacillus globigii and Streptococcus epidermidis were $10^5CFU/m{\ell}\;and\;5{\times}10^5CFU/m{\ell}$ respectively when samples were sonificated for 20 seconds with a sonificator probe of 13 mm diameter.

• Journal of Environmental Science International
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• v.25 no.3
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• pp.439-446
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• 2016

Domestic sewerage treatment plant is operated by activated sludge method and its modified method by using microorganism. In most cases, a method of using microorganism is directly controlled by the operator based on individual judgment through factors of DO, pH and ORP. In addition, under aerobic condition in bioreactor, energy consumption including excessive air injection is learned to be somewhat plenty. In order to solve this problem, in most of the process, improvement of internal recycling and activated environmental factor of microorganism were researched extensively. However, as factors are changed depending on various conditions, it is not sufficient as an indicator of judgment. As such, a research on operation of bioreactor that measures metabolic change in short time by directly measuring activated condition of microorganism using NADH fluorometer is required in reality.It is considered that the method like this could supplement problem of energy consumption being occurred in the existing treatment method and operational optimization of bioreactor would be enabled by controlling optimal air volume. Therefore, in this study, in order to obtain optimal operational indicator of bioreactor, proper air volume control test was performed and through batch test and site evaluation, possibility of NADH sensor being utilized as operational control indicator of bioreactor is intended to be analyzed. In order to compare with measured value, DO, ORP that are operational control indicator of existing bioreactor were used. As MLSS concentration was increased through batch test, NADH value was increased and site evaluation also showed similar tendency to batch test. Resultantly, it could be confirmed that changing level of NADH fluorometer was a sensor that could measure bioreactor condition effectively and optimized scale of bioreactor is considered to be utilized.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.3
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• pp.219-223
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• 1987

A slightly modified method of Rashid and Potts(1980) to determine riboflavin in milk in which lead acetate was used as a precipitant was employed in tile present study to test applicability to determine that of fish as well. The lead acetate method was found to be sensitive, simple, inexpensive and rapid compared to the modified A.O.A.C. method by Cordon et al. (1979). But higher riboflavin values were obtained in this study than those reported so far. The riboflavin contents of 9 white fleshed fishes were in the range of $0.29\~0.48mg$ per 100g fresh sample. Linear regression equation Y=125.70X+0.71 (R=0.9993) was obtained for the calculation of riboflavin content in the white fleshed fish. Y is the concentration of riboflavin in the final solution to be chocked its OD at fluorometer and X is the dial reading of fluorometer. The stability of riboflavin as the freshness changes during icing storage$(at\;0^{\circ}C)$ was studied with file fish. During the initial stage of storage, the riboflavin content was found to by increased by $14\%$, but the difference was not statistically significant (p>0.05). K-value and VBN-value were increased along with storage time, but Proximate composition was not changed significantly during entire storage of 18 days.

• ALGAE
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• v.25 no.2
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• pp.89-97
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• 2010

To test the feasibility of using chlorophyll ${\alpha}$ fluorescence to assess the establishment success of seagrass transplants, photosynthetic characteristics of eelgrass Zostera marina transplants were measured using a Diving-pulsed amplitude modulation fluorometer in Jindong Bay on the southern coast of Korea. Maximum quantum yield ($F_v/F_m$), photosynthetic efficiency ($\alpha$), saturating irradiance ($E_k$) and maximum electron transport rate ($ETR_{max}$) of transplants and reference plants in a nearby transplant site were measured using the fluorometer for 5 months. Additionally, shoot morphology, individual shoot weight and productivity of transplants and reference plants were also monitored. Shoot height, leaf weight and productivity of transplants were significantly reduced during the first two or three months after transplantation compared to those of reference plants, and then increased to the levels of reference plants Characteristics of chlorophyll a fluorescence, including $F_v/F_m$, $\alpha$, $E_k$ and $ETR_{max}$ of transplants were also significantly reduced in the initial period, but recovered slightly sooner than shoot morphology or leaf productivity. These results indicated that after transplantation, Z. marina transplant photosynthesis recovered faster than shoot morphology, biomass or productivity. Thus, chlorophyll a fluorescence can be used as an indicator for early assessment of the status of eelgrass transplants without destructive sampling.