• Journal of Environmental Health Sciences
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• v.31 no.2 s.83
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• pp.147-151
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• 2005

The disinfection effect of free residual chlorine and monochloramine on biofilm communities were investigated by CLPP (community level physiology profile) using Biolog GN plates. Low concentration of disinfectant, $0.5\;mg/\iota$ free chlorine and $1.0\;mg/\iota$ monochloramine, stimulated the growth of bacteria rather than disinfection. Bacterial concentrations were decreased at more than $1.0\;mg/\iota$ of disinfectants. CLPP was different with the type and concentration of disinfectant and sampling time. Common and different carbon sources were actively used with similar bacterial concentration in free chlorine and monochloramine. This represents the differences of bacterial communities with tap water contact times and disinfectant.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.5
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• pp.30-36
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• 2001

Caro's acid (persulphuric acid) has been proposed as a promising reagent used in pulping of lignocellu-losic materials. Bagass was subjected to caro's acid pulping under different pulping conditions of per acid concentration (2~8 percent), pulping temperatures (40~$60^{\circ}C$) and pulping time (120~240 min). The influence of different parameters of caro's acid pulping process on the chemical and strength properties of the produced pulps had been studied. Peracid concentration and pulping temperature are the most important variables of the pulping process. High degree of delignification and good deliberation were achieved at moderate pulping conditions in the studied range. Pulping experiments of bagasse by using caro's acid had been carried out for determination of the optimum comditions of the process. In inch case to effectively tackle the problem, a specific design of an experiment is selected depending on the goals to be achieved in the experimentation. The study could enable us to excepect the bagasse pulp properties (yield, Kappa number, DP) that be stated as function of the independent variables of caro's acid pulping process (per acid concentration, pulping temperature and pulping time).

• Bulletin of the Korean Chemical Society
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• v.19 no.9
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• pp.923-926
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• 1998

Spectral diffusion following direct triplet excitation from the ground state in glassy Methylbenzophenone as a function of transition energy has been studied. The concentrations of donor and acceptor have been determined for different transition energies. The geometrical distribution was determined by a computer simulation. The cluster size increases gradually with concentration and cluster percolation is observed at 0.31 mole fraction for a three dimensional system. The average distance between a donor and an acceptor also has been determined for different concentrations. The energy transfer efficiency changes abruptly at a critical concentration of 0.054, corresponding to a critical distance of 9.8 Å. The γvalue was evaluated to be 1.17.

• Journal of Environmental Science International
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• v.13 no.12
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• pp.1103-1108
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• 2004

This experiment was carried out to investigate the effects of cadmium on the growth of Arabidopsis thaliana when they were treated with different concentrations of cadmium. The growth of stem was stimulated in the concentrations up to fifty times higher than the official standard concentration of cadmium of pollutant exhaust notified by the Ministry of Environment, but it decreased in the concentration one hundred fifty times or more higher in proportion to the degree of concentration. The growth of root was similar to that of stem, except that the decrease was gradual in the concentration fifty times or more higher. The growth of leaf was almost the same as that of stem, that is, it was stimulated the increase of leaf surface area in the concentration fifty times higher, but decreased in the concentration one hundred fifty times or more higher in proportion to the degree of concentration. The fresh weights of the plants were increased in accord with the degree of growth of the stem and leaf. Concentration of cadmium accumulated in the plants was increased in proportion to the concentration of cadmium. These results show that the growth of plants was stimulated in the soil polluted by cadmium up to fifty times higher than the official standard concentration, but it was decreased in proportion to the degree of concentration in the plants grown in the presence of cadmium more than one hundred fifty times.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.466-469
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• 2005

Chinese cabbage (Brassica campestris L. Pekinensis) is Brassica vegetable that contains high amounts of glucosinolates. Glucosinolates and their breakdown products are thought to contribute to health promotion by preventing some cancers. Chinese cabbage is the most commonly consumed vegetable in Asian countries including Korea. In this study, qualitative and quantitative analyses of 3-butenyl glucosinolate (Gluconapin) from different cultivars and different parts of the cabbage were performed. Gluconapin of Chinese cabbage was extracted by hot ethanol ($80^{\circ}C$), isolated by an anion exchange column and identified by GC/MS and LC/MS. The levels of glucosinolates in Chinese cabbage varied according to the different parts, cultivars, and blanching time. In general, the concentrations of 3-butenyl isothiocyanate (ITC) were higher in the leaf than in the midribs parts. The cultivar 'Bulam no. 3' had a much greater content of 3-butenyl ITC than the cultivar 'Garak no. 1,' and the levels of butenyl ITC were highest after two weeks of storage. Blanching treatment decreased the concentration of 3-butenyl ITC. The ITC concentration varied extensively among different crops of the same species, and according to the different parts on the cabbage, the storage duration and the boiling time.

• Journal of Nutrition and Health
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• v.29 no.5
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• pp.472-479
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• 1996

To investigate the effect of dietary lipids and stress on brain catecholamine and serotonin concentration, sixty three weanling male Sprague-Dawley rats(mean body weight$\pm$SD : 171$\pm$3g) were fed a diet containing fish oil, soybean oil or beef tallow and than, each was exposed to three different types of stress, isolated, grouped or cold, respectively. Cold stress seemed to be most severe and living together in a large cage with some playing equipments is more stressful than living alone in a classical small cage evidenced by plasma corticosterone level. Average food intake and body weight gain were not significantly different among exprimental groups. In adrenal catecholamines, norepinephrine was significantly affected by diet and stress and dopamine was by stress. Norepinephrine concentration of the fish oil group was lowest among diet groups. Adrenal epinephrine, however, was not. It was also shown than the cold stress significantly increased the brain norepinephrine concentration. The cold stress significantly induced higher content of brain serotonin than the grouped stress. However, the concentratin of 5-hydroxyindoleacetic acid(5-HIAA), the metabolite of serotonin, was not significantly different among groups. Therefore, this results suggest that stress affects sympathetic neuronal activity, and fish oil might lighten the burden of stress.

• Korea-Australia Rheology Journal
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• v.14 no.1
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• pp.1-9
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• 2002

Steady and dynamic shear properties of two hydrophobically modified alkali soluble emulsions (HASE), NPJI and NPJ2, were experimentally investigated. At the same polymer concentration, NPJ1 is appreciably more viscous and elastic than NPJ2. The high hydrophobicity of NPJ1 allows hydrophobic associations and more junction sites to be created, leading to the formation of a network structure. Under shear deformation, NPJ1 exhibits shear-thinning behaviour as compared with Newtonian characteristics of NPJ2. NPJ1 and NPJ2 exhibit a very high and a low level of elasticity respectively over the frequency range tested. For NPJ1, a crossover frequency appears, which is shifted to lower frequencies and hence, longer relaxation times, as concentration increases. Three different surfactants anionic SDS, cationic CTAB, and non-ionic TX-100 were employed to examine the effects of surfactants on the rheology of HASE. Due to the different ionic behaviour of the surfactant, each type of surfactant imposed different electrostatic interactions on the two HASE polymers. In general, at low surfactant concentration, a gradual increase in viscosity is observed until a maximum is reached, beyond which a continuous reduction of viscosity ensues. Viscosity development is a combined result of HASE-surfactant interactions, accompanied by constant rearrangement of the hydrophobic associative junctions, and electrostatic interactions.

• Journal of environmental and Sanitary engineering
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• v.11 no.2
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• pp.27-31
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• 1996

2,4,6-Trinitrotoluene(TNT) was reduced into intermediate products by mixed culture incubated in anaerobic condition. To test the effects of extracellular material to electron transfer between sulfide and TNT, filtered medium of mixed culture was loaded in the test tubes with TNT and sulfide. The transformation rate was measured under four different conditions. The rate under microbial activity was the fastest among under different conditions. With sulfide or filtrate alone and TNT, the reactions were measured as the slowest reactions or no reactions occured, respectively. The reaction rate coefficient were calculated by linear regression and the first order kinetic was fitted best. Also, the plot of rate coefficients (K$_{f}$) showed linear relationships when at time zero TNT and sulfide concentration were 20 mg/1 and 6.0 mM, respectively. By extrapolation, reaction rate coefficient of 100% filtrate could be calculated as 0.0054/minute. However, reaction rate was affected by different concentration of sulfide, so it is a dependent of sulfide concentration. The results of this test showed TNT reduction rate can be limited more by microbial reaction than by mediation of filtrate or sulfide and filtrate alone.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.481-486
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• 2017

The content of $N^{\varepsilon}$-(carboxymethyl)lysine (CML), an advanced glycation endproduct, in stir-fried anchovy prepared under different cooking conditions was determined, along with their sensory properties. The aim of the study was to optimize cooking conditions of stir-fried anchovy for minimal CML production by using different sugars, sugar concentrations, pH levels, and cooking times. The results showed that CML content increased with increasing sugar concentration. Cooking time did not affect CML content but lowering the pH with lemon juice decreased it significantly. The CML content of samples with a high sugar concentration, and without lemon juice was $4.67{\mu}g/mL$, and that of samples with both a low sugar concentration and lemon juice was $2.49{\mu}g/mL$, indicating a 47% reduction in the CML content of sir-fried anchovy. We conclude that stir-fried anchovy cooked with less sugar and the addition of lemon juice can reduce CML content while maintaining sensory characteristics.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.173-173
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• 2017

Phalaenopsis orchid is one of the most important flowers in flower industry. We conducted an experiment to find out the response of different concentration of chlorocholine chloride (CCC) for the in vitro regeneration of protocorm like bodies (PLBs) of Phalaenopsis 'Fmk02010'. We used five different concentrations of CCC and these were 0 (control), 0.01, 0.1, 1 and $10mgL^{-1}$ in modified MS medium and cultured for 42 days. We added two major salts ammonium nitrate ($412.5mgL^{-1}$) and potassium nitrate ($950.0mgL^{-1}$) to the MS medium for the modification. Maximum numbers of PLBs were found from media with $0.01mgL^{-1}$ of CCC (15.667) and maximum fresh weight (0.211 g) as well. The 100% PLB formation rate was also found from $0.01mgL^{-1}$ of CCC. We found 58.83% variation in number of PLBs ($R^2=0.5883$) and 47.44% variation in fresh weight ($R^2=0.4744$) to the different CCC concentrations. Our study suggested that increase in the CCC concentration negatively affect the PLBs organogenesis of Phalaenopsis. We can suggest that the addition of very low concentration of CCC in plant culture medium can increase the number, formation rate and fresh weight of PLBs of Phalaenopsis.