• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.11-19
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• 2000

In order to predict the performance of biological wastewater treatment plant, the kinetic parameters and stoichiometric coefficient must be known. The theories and experimental procedures for determining the biological kinetic parameters were discussed in this study. Respirometric analysis in the batch reactor was carried out for the experimental assessment of kinetic parameters. A simple procedure to estimate kinetic parameters of heterotrophs and autotrophs under aerobic condition was presented. The difficulties in the interpretation of COD and VSS measurements encouraged the conversion of respirometric data to growth data. Maximum specific growth rate, yield coefficient, half saturation constant and decay rate of heterotrophic biomass were obtained from OUR(Oxygen Uptake Rate) data. Maximum specific growth rate of autotrophic biomass was obtained from the increase of nitrate concentration. The aim of this paper is to estimate the kinetic parameters of heterotrophic and autotrophic biomass by means of the respirometric analysis of activated sludge behavior in the batch reactors. These procedures may be used for the activated sludge modeling with complex kinetic parameters.

• Korean Chemical Engineering Research
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• v.60 no.1
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• pp.80-85
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• 2022

In wastewater treatment processes huge quantities of sludge are produced continuously each year. This work investigated the reuse of two types of sludge as biosorbents of a toxic dye. The potential of granular and filamentous fungus dried sludge for the elimination of eosin from aqueous solution was studied in batch system. The effect of initial concentration and temperature was examined. Maximum uptake was observed at 100 mg l^-1 and 30 ℃. The maximum removal rate was 92% for the granular sludge and 90% for the filamentous one. Equilibrium was attained after 30 min for the studied dye concentrations. The equilibrium uptake increased with the initial eosin concentration. The Freundlich and Langmuir adsorption models were also investigated. The reuse of disposed sludge as adsorbent could be a solution for the valorization of such dangerous waste to resolve two environmental problems at the same time.

• Korean Journal of Microbiology
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• v.26 no.2
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• pp.129-136
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• 1988

To investigate the influence of cosubstrate supplement and ammonium sulfate on lignin degradation by Pseudomonas diminuta KM-4-2, isolated in the laboratory, the strain was cultured on the lignin media which contained lignin as a source of carbon and the culture filtrate was analyzed by Sephadex G-75 column chromatography. It was found that polymerization was not appeared unlike wood-rot fungi. When the carbohydrates were added, the peak of lignin at 280nm by UV scanning spectra of the filtrate, was significantly increased. In order to determine the effect of ammonium sulfate on the ligninolytic activity, the isolated strain was incubated in the media containing 0.1%, 0.25% and 0.5% of nitrogen concentration in the Warburg flask and the rate of oxygen uptake was esitmated by Warbuge Respirometer. As a result, the activity was maximum at 0.1% of nitrogen concentration and thereafter decreased in parallel with nitrogen concentration.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.4
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• pp.196-205
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• 2011

To investigate the contribution of macroalgae to biogeochemical nutrients and carbon cycles, we measured the uptake rates of nutrients and $CO_2$ and characteristics of fluorescence of Saccharina japonica (Laminaria japonica Areschoug) using an incubation method in an acrylic chamber. From January to May 2011, S.japonica was sampled at Ilkwang, one of well-known macroalgae culture sites around Korea and ranged 46~288 cm long and 4.8~22.0 cm wide of whole thallus. The production rate of dissolved oxygen by S. japonica (n=25) was about $6.9{\pm}5.8{\mu}mol\;g^{-1}$ fresh weight(FW) $h^{-1}$. The uptake rate of total dissolved inorganic carbon ($TCO_2$), calculated by total alkalinity and pH, was $8.9{\pm}7.9{\mu}mol\;g^{-1}\;FW\;h^{-1}$. Mean nutrients uptake were $175.6{\pm}161.1\;nmol\;N\;g^{-1}\;FW\;h^{-1}$ and $12.7{\pm}10.1\;nmol\;P\;g^{-1}\;FW\;h^{-1}$. There were logarithmic relationships between thallus length and uptake rates of nutrients and $CO_2$, which suggested that younger specimens (<100-150 cm) were much more efficient at nutrients and $CO_2$ uptake than old specimens > 150 cm. There was a positive linear correlation ($r^2$=9.4) existed between the dissolved oxygen production rate and the $TCO_2$ uptake rate, suggesting that these two factors may serve as good indicators of S. japonica photosynthesis. There was also positive linear relationship between maximal quantum yield ($F_v/F_m$) and production/uptake rates of dissolved oxygen, $TCO_2$ and phosphate, suggested that $F_v/F_m$ could be used as a good indicator of photosynthetic ability and $TCO_2$ consumption of macroalgae. Maximum relative electron transport rate ($rETR_{max}$) of S. japonica increased as thallus grew and was high in distal part of thallus which may be resulted from the increase of photosynthetic cell density per area. The annual $TCO_2$ uptake by S. japonica in Gijang area was estimated about $1.0\sim1.7{\times}10^3C$ ton, which was about 0.02-0.03% of carbon dioxide emission in Busan City. Thus, more research should be focused on macroalgae-based biogeochemical cycles to evaluate the roles and contributions of macroalgae to the global carbon cycle.

• The Research Journal of the Costume Culture
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• v.24 no.6
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• pp.777-787
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• 2016

This study was carried out in order to provide useful data for planning fabrics of summer eco-friendly fashion products. The fabrics used in this study were four cellulose fibers: cotton, cotton/mulberry blended, flax, and flax/lyocell blended. Dyeing with natural indigo was carried out under three different reducing conditions (i.e., general, eclectic, and eco-friendly) that have different reducing agent and pH levels, and hydrosulfite and glucose were used as a reducing agent. The dye uptake (K/S value) of fabrics dyed with natural indigo by a reducing condition was the highest at 660nm. Regardless of the fabrics, dye uptake was the highest under the general reducing condition and the lowest under the eco-friendly reducing condition. Under different reducing conditions, the dye uptake of natural indigo fabrics with the maximum absorption wavelength indicated a difference. The colorfastness of cellulose fabrics that were dyed with natural indigo had a rate of 4 to 5 except for rubbing fastness, which indicated good colorfastness. Additionally, natural indigo-dyed cotton and flax fabrics had good antibiosis. When the color characteristics of fabrics dyed with natural indigo were measured, all of the three reducing conditions created purple blue (PB) colors, and the color characteristics of dyed fabrics by reducing condition and fabric showed significant differences.

• Journal of Plant Biology
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• v.25 no.4
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• pp.153-160
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• 1982

The kinetics of $^{14}C$ fixation have been investigated in Anabaena flos-aquae growing on ${NH}_4+$,$NO_3-$ and $NO_2-N$ in batch cultures. Growth rate was highest with ${NH}_4+$, followed by $NO_2-$ and finally $NO_2$. The compensation intensity($I_0$) and the half-saturation irradiance($K_1$) with $K_1$ were higher than with other N sources, but the maximum C fixation rate($P_{max}$) was lower. The ($P_{max}$)/$K_1$ ratio, which is analogous to quantum efficiency at low irradiance ranges, was also lower with $N_2$. All these parameters except $K_1$ decrease with culture age, or decreasing growth rate. Since $^{14}C$ uptake measures net photosynthesis, the higher values of $I_0$ and $K_1$, and the low values of $P_{max}$/$K_1$ ratio with $N_2$ appear to be related to the high energy demand of $N_2$fixation. They may also be related to the lox maximum growth rate with $NO_2-N$.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.3
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• pp.223-229
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• 2006

In this study, we have conducted kinetics and modelling studies of Centella asiatica cell growth and substrate uptake, in an attempt to evaluate cell growth for a better understanding and control of the process. In our bioreactor cultivation experiment, we observed a growth rate of 0.18/day, a value only 20% higher than was seen in the shake flask cultivation trial. However, the observed maximum cell dry weight in the shake flask, 10.5g/L, was 14% higher than was achieved in the bioreactor. Ninety seven percentage confidence was achieved via the fitting of three unstructured growth models; the Monod, Logistic, and Gompertz equations, to the cell growth data. The Monod equation adequately described cell growth in both cultures. The specific growth rate, however, was not effectively predicted with the Logistic and Gompertz equations, which resulted in deviations of up to 73 and 393%, respectively. These deviations in the Logistic and Gompertz models may be attributable to the fact that these models were developed for substrate-independent growth and fungi growth, respectively.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.485-492
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• 1996

myo-Inositol, a growth factor for Saccharomyces cerevisiae (S. cerevisiae), has been known to be incorporated into phosphatidylinositol (PI), which is a kind of phospholipid in the cell membrane, by a membrane-associated PI-synthesizing enzyme. The deficiency of myo-inositol in S. cerevisiae adversely affected the membrane structure and function. On the basis of biochemical functions of myo-inositol, the effect of deficiency of myo-inositol on the aerobic glucose metabolism was investigated by measuring specific oxygen uptake rate (Q$_{O2}$) used as an indicator representing the respiratory capacity of S. cerevisiae in batch and continuous cultures. The respiratory capacity of aerobic glucose metabolism in S. cerevisiae was also monitored after glucose pulse-addition in a continuous culture (D=0.2, 1/hr), in which glucose was utilized through respiratory metabolism. The deficiency of myo-inositol was found to lead to both the decrease of the maximum specific oxygen uptake rate (Q$_{O2max}$) observed from the batch as well as in the continuous culture experiment and the decrease of the respiratory capacity of aerobic glucose metabolism of S. cerevisiae determined from the glucose pulse-addition experiment, in which the glucose flux into respiratory and fermen- tative metabolism was quantitatively analyzed.

• Journal of Korean Society on Water Environment
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• v.22 no.3
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• pp.566-571
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• 2006

A sequencing batch biofilm reactor (SBBR) operated with a cycle of anaerobic - aerobic - anoxic - aerobic has been evaluated for the nutrient removal characteristics. The sponge-like moving media was filled to about 10% of reactor volume. The sewage was the major substrate while external synthetic carbon substrate was added to the anoxic stage to enhance the nitrogen removal. The operational results indicated that maximum T-N and T-P removal efficiencies were 97% and 94%, respectively were achieved, while COD removal of 92%. The observations of significant nitrogen removal in the first aerobic stage indicated that nitrogen removal behaviour in this SBBR was different to conventional SBR. Although the reasons for aerobic nitrogen removal has speculated to either simultaneous nitrification and denitrification or anoxic denitrification inside of the media, further researches are required to confirm the observation. The specific oxygen uptake rate (SOUR) test with biofilm and suspended growth sludge indicated that biofilm in SBBR played a major role to remove substrates.

• Journal of Korean Society on Water Environment
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• v.18 no.3
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• pp.291-301
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• 2002

In this study, nutrients treatment by sequencing batch reactors(SBR) was performed. Nitrogen and phosphorus removal efficiencies were evaluated by changing SRT and mixing/aeration ratio. Not only nitrogen but also phosphorus removal patterns were investigated through track studies on 1 cycle. As SRT was fixed and mixing/aeration ratio was changed, maximum nitrogen removal efficiency was 87.6% at mixing/aeration ratio 0.67. Phosphorus removal efficiencies were more than 85.5% except no mixing condition. As mixing/aeration ratio was fixed and SRT was changed, nitrogen removal efficiencies were 70.5~79.8%, which represented slight changes, while phosphorus removal efficiencies were 49.0~97.3%, which represented sharply decreasing tendency at less than 20 day. Both phosphorus release rate k and maximum phosphorus release rate $P_{max}/M$ were are decreased as SRT was decreased, but they were not affected by mixing/aeration ratio. It was found that there is a linear relationship between ortho-phosphate uptake and maximum ortho-phosphate release.