• Journal of Environmental Health Sciences
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• v.33 no.5
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• pp.428-433
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• 2007

To clarify the pioneer group in the development of biofilms in high chlorine residual water, a semi-pilot model system was operated and 16S rDNA V3 targeted PCR-DGGE was submitted. Biofilm formation occurred rapidly in the model of a drinking water distribution system. It reached $10^3\;CFU/cm^2$ or more on the surface of stainless steel, PVC, and galvanized iron in chlorinated (1.0 mg/l) water within a week. Within a week, uncultured Proteobacteria- and Bacillales group-like sequences were detected and Sphingomonas-like sequences were identified from all season and all pipe materials tested. Hence Sphingomonas species were regarded as the potential pioneer group in the development of biofilm in drinking water and this results would be useful for the prevention of biofilm formation and safety of drinking tap water.

• Journal of environmental and Sanitary engineering
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• v.9 no.2
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• pp.58-62
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• 1994

Until 1960 water pollution was caused by virus but now in according to industrial develop cent it has been continued environmental pollution by surfactant heavy metal, and hazardous chemical substance erst.. It is possible to Prevent contamination by virus owing to development of antibiotic but not to dissolve basely health effect by hazardous chemical substances because it takes very long time, about 5-40 years, average 20 years, in appearing a disease after exposure by then To maintain human life for 75 years, it need 55 ton of water. In the experiment of Public Health Institute, Tokyo, they reported that over 200 chemical substances can be detected in case of human being to drink tap water of Tokyo(1989) continuously. In our country, elevation of life style and development of industry result in increase of water use and overappreciation of pesticides in farm land a(sects drinking water quality. We estimated analytical item of drinking water hygienically by dividing into 5 groups such as physical effect item health hazardous inorganic item and health hazardous organic item ect. based on hygienic purpose.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.460-467
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• 2009

This research was conducted for the purpose of investigating the influence substrates addition such as germanium or Granite porphyry gravel have on the growth of foliage, on the inorganic compositions of leaves as well as on root activity, in order to discover effective means of introducing plants to the indoors. Syngonium podophyllum, Dracaena sanderiana, Epipremnum aureum and Hedera helix were used as study subjects to which soil (mixed top-soil: Sunshine Mix No. 2, USA), tap water, tap water with germanium (300g), tap water with Granite porphyry gravel (300g) were added respectively and formulated. Studies on growth variations according to substrates addition indicate that growth of Syngonium podophyllum was most sluggish under tap water only treatment. Plant growth was most active under geranium-gravel treatment. In the case of Dracaena sanderiana, treatment of substrates addition had no meaningful influence on plant growth. However, the growth of Epipremnum aureum and Hedera helix was also shown to be most active under geranium-gravel treatment. Geranium-gravel treatment was shown to be particularly beneficial for root length, number of roots and dry weight. Root activity was analyzed on ten day intervals and there was discernable difference in the root activity of all the plants according to the varying treatments. In the case of the Syngonium podophyllum, the root activity was sluggish in all three types of treatment on the 10th day but improved gradually. On the 30th to the 50th day of the experiment, the root activity was found to be best under the Granite porphyry gravel treatment. In the case of the Dracaena sanderiana, the root activity was most active under the geranium-gravel treatment from the 10th to the 40th day but deteriorated from the 50th day. However, there was no significant different in all three treatments from the 60th day onwards. Analysis of the inorganic components of the leaves indicates that, while Ca and Mg were higher in the geranium than in the Granite porphyry gravel, they do not directly influence the content of inorganic components in the leaves. The results indicate that Epipremnum aureum and Hedera helix grow better under hydro-culture than when grown in soil and growth under hydro-culture is shown to increase when germanium is added to tap water.

• Analytical Science and Technology
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• v.31 no.2
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• pp.96-105
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• 2018

This study aimed to improve the method for detecting eight secondary aliphatic amines (SAAs), so as to measure their concentrations in fresh water and tap water samples. NaOH (8 mL, 10 M) and benzenesulfonyl chloride (2 mL) were added to a water sample (200 mL), and the mixture was stirred at $80^{\circ}C$ for 30 min. An additional NaOH solution (10 mL) was added and the stirring was continued for another 30 min. The pH of the cooled mixture was adjusted to 5.5-6.0 by adding HCl (35 %), and the SAAs were extracted using dichloromethane (50 mL). This extraction was repeated once. The extract was then washed with $NaHCO_3$ (15 mL, 0.05 M) and dried over $Na_2SO_4$ (4 g). The extract was finally concentrated to 0.1 mL, of which $1{\mu}L$ was analyzed for SAAs by GC-MS. The linearity of the spike calibration curves was high ($r^2=0.9969-0.9996$). The detection limits of the method ranged from 0.01 to $0.20{\mu}g/L$, and its repeatability and reproducibility (expressed as relative standard deviation) were both less than 10 % (6.6-9.4 %). Its accuracy (measured in percentage error) ranged between 2.4 % and 6.1 %. The established method was applied to the analysis of five surface water and 82 tap water samples. Dimethylamine was the only SAA detected in all the water samples, and its average concentration was $0.79{\mu}g/L$ (range: $0.20-2.54{\mu}g/L$). Therefore, this study improved the analytical method for SAAs in surface water and tap water, and the regional and seasonal concentration distributions were obtained.

• Korean Journal of Veterinary Research
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• v.30 no.1
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• pp.15-27
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• 1990

Effects of oral administration of electrolyte solutions were studied in experimentally dehydrated adult sheep. By the latin square method five ruminal fistulated sheep were examined and dehydrated by deprivation of feed and water for 72 hours. Tap water, physiological saline, 0.45% NaCl+120 mM/L glucose and 0.9% NaCl+1% propylene glycol solution were orally administrated after dehydration, respectively. Rehydration effect and modification of the rumen function were compared. 1. After 72 hours of deprivation of feed and water, sheep were hypertonic dehydrated and blood acid-base parameters were not significantly changed. And there was marked increase in ruminal pH and decrease in ruminal total volatile fatty acid(VFA) concentration. 2. After the fluids administration the changes in blood acid-base parameters were not significant in all groups. 3. Although glucose fermentation in the rumen was observed, 0.45% NaCl+120 mM/L glucose was more effective in rehydration than physiological saline and tap water. But it was difficult to know the rehydration effect of 0.9% NaCl+1% propylene glycol solution exactly because of excessive increase in plasma osmolality. 4. After refeeding, total concentration and proportions of ruminal volatile fatty acid(VFA) were not significantly different among groups and recovered to normal concentration but not in proportions after 2 days in all groups. 5. In vitro cultured ruminal protozoa were susceptible to the decrease of the pH and osmolality.

• Journal of Life Science
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• v.14 no.6 s.67
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• pp.891-894
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• 2004

The effect of pipe materials on biofilm communities were investigated by CLPP (community level physiology profile) using Biolog GN plates. Heterotrophic bacterial concentrations were $10^4\;-\;10^6\;CFU/cm^2$ and there was no differences between galvanized iron and carbon steel. Average optical density of Biolog plate was similar between two pipe materials. However, CLPP was different according to the type of pipe materials and exposed times to tap water, and CLPP was independent of bacterial concentration. This represents the differences of bacterial communities with pipes and water contact times.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.259.1-259.1
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• 2014

Recently non-thermal plasma has been frequently applied to various research fields. The liquid plasma have received much attention lately because of interests in surgical and nanomaterial synthesis applications. Especially, intensive researches have been carried out for non-thermal plasma in liquid by using various electrode configurations and power supplies. We have developed a bioplasma source which could be used in a liquid, in which outer insulator has been covered onto the outer electrode. Also we have also put an insulator between the inner and outer electrode. Based on the surface discharge mode, the nonthermal bioplasma has been generated inside a liquid by using an alternating current voltage generator with peak voltage of 12 kV under driving frequency of 22 KHz. Here the discharge voltage and current have been measured for electrical characteristics. Especially, We have measured discharge and optical characteristics under various liquids of deionized (DI) water, tap water, and saline by using monochromator. We have also observed nitric oxide (NO), hydrogen peroxide (H2O2), and hydroxyl (OH) radical species by optical emission spectroscopy during the operation of bioplasma discharge inside various kinds of DI water, tap water, and saline. Here the temperature has been kept to be $40^{\circ}C$ or less when discharge in liquid has been operated in this experiment. Also we have measured plasma temperature by high speed camera image and density by using either H-alpha or H-beta Stark broadening method.

• Structural Monitoring and Maintenance
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• v.11 no.3
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• pp.247-262
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• 2024

Domestic sewage can greatly affect the macro-micro physical-mechanical properties of building foundation soils. In order to investigate the effect of domestic sewage on physical and mechanical properties of soils, the physicochemical properties of three groups of different concentrations of domestic sewage contaminated soil were tested through indoor experiments. Combined with scanning electron microscopy, X-ray diffraction experiments, and grey relational analysis, the degree of influence of different concentrations of domestic sewage on the physicochemical properties of soil was compared and analyzed from multiple perspectives such as microstructure and mineral composition, revealing the influencing mechanism of soil pollution by domestic sewage. The results showed that under the immersion of contaminated water, the color of the soaking water turned black first and then yellow, and brownish yellow secretions appeared on the surface of the soil samples. The moisture content, specific gravity, density, and pore ratio index of the soil samples immersed in 50% and 100% domestic sewage decreased with the increase of sewage concentration, while the liquid limit of the soil samples changed in the opposite direction. The immersion time had little effect on the slope of the compression curve of the soil samples soaked in tap water. For the soil samples immersed in domestic sewage, the slope of the compression curve and the compression coefficient increased with the increase of domestic sewage concentration and immersion time, while the compression modulus showed the opposite trend. In the soil samples immersed in tap water, there were a large number of small particles and cementitious substances, and the structure was relatively dense. With the increase of domestic sewage concentration, the microstructure of the soil changed significantly, with the appearance of sigle particle structure, loose and disorderly arrangement of particles, increased and enlarged pores, gradual reduction of small particle substances and cementitious substances, and the soil structure transformed from compact to loose. The research findings can provide theoretical reference for contaminated geotechnical engineering.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.3
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• pp.333-339
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• 2010

Particle removal is an important step taken at water treatment plants (WTPs) for the safety of tap water due to its proportionality to the pathogen inactivation. Government promulgated a treatment technique for the optimization of filtration including continuous turbidity monitoring using on-line turbidimeters. Based on the turbidity measurements of 460 filters at 31 WTPs operated by K-water, the evaluation of filtration performance and the investigation of major causes related to particle breakthrough were explored. 98.1 % of the filters had an effluent turbidity measurement which was less than 0.1 NTU, but turbidity breakthrough of more than 0.3 NTU was noticed occasionally which is in violation of AWWA 5-Star guidelines. It was shown that the optimization of coagulation, filter-to-waste, the observance of optimal filtration velocity and backwashing process based on filtrate turbidity were crucial for the improvement of filtrate.

• Journal of Korean Academy of Nursing
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• v.41 no.2
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• pp.269-275
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• 2011

Purpose: This study was done to identify effects of carbonated water intake on constipation in elders who have experienced a cerebrovascular accident (CVA) and are bed-ridden. Methods: Forty elderly patients with CVA were randomly assigned to one of two groups in a double-blind study. Patients in the experimental group drank carbonated water and those in the control group drank tap water for two weeks. Six patients dropped out during the study period. Data were analyzed by repeated measured ANCOVA and the covariance was the dose of laxatives used for the two weeks. Results: Frequency of defecation increased significantly and symptoms of constipation decreased significantly for patients in the experimental group. Conclusion: The study results suggest that the intake of carbonated water is an effective method for the intervention of constipation in elderly patients with CVA.