• Fashion & Textile Research Journal
• /
• v.6 no.3
• /
• pp.393-398
• /
• 2004

This research offers recycling method of NaOH from mercerizing process of cotton fabric. The measuring system of NaOH concentration was designed for the mercerizing process and tested for various conditions which can be occurred in factory. The accuracy of the system was varied as the testing condition was changed. As the concentration of sulfuric acid used for titrating NaOH decreased, the accuracy of measuring system increased. The concentration of NaOH for waste water collected from mercerizing process was measured by 5.2%. As the ratio of newly mixed NaOH increased, moisture regain. water absorbency and whiteness of the specimen increased. The bending rigidity(B) and shear rigidity(G) decreased, as the ratio of newly mixed NaOH increased.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.24 no.4
• /
• pp.80-91
• /
• 1982

To precict the suspended sediments which are 80% of total sediments in a flood disch- arge, an equation representing vertical distribution of sediment concentration was derived based upon the diffusion theory and the logalithmic velocity distribution function in the tubulent flow mechanism. The hypothesis that the uniform mass transfer is occurred at upper part along the center line of water depth, was established as a preconition to solve the problem. The theorecal and the observed values were compared. And the theoretical equation was modified to be fit the theoretical values the observed values. Observed results are as follow; 1) Equation 12) is the theoretical equation representing the vertical concentration distri- bution of suspended sedimenta 2) Rous&exonential type vertical concentration distribution equation shows signification errors near the water surface. But the equation 12) shows substation cocentration values near the water surface. 3) Equation 15) is the modified theoretical equation which is possible to predict the vertical concentration distribution of suspended sediments.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2005.10a
• /
• pp.389-394
• /
• 2005

In this study we carried out to evaluate the salinity concentration and volumetric water content of unsaturated soil column using frequency domain Reflectometry with vector network analyzer (FDR-V) measurement system. All of experiments were considered to the effect of temperature which ranges from l0$^{\circ}C$ to 50$^{\circ}C$ increasing the interval of l0$^{\circ}C$ controlled by the constant temperature container. From the results the responses of complex dielectric constant which consist of the real part and imaginary parts have the effect of volumetric water content and concentration of salinity at 1GHz. Use of derived equations (1) and (2) can be calculated the physical parameters such as volumetric water content and salinity concentration of unsaturated media by the responses of complex dielectric constant.

• Journal of environmental and Sanitary engineering
• /
• v.21 no.4 s.62
• /
• pp.29-38
• /
• 2006

This study included the development of analytical method for determining perchlorate in water sample. The analytical condition was referred in EPA 314.0 method which use ion chromatography and the concentrator column was replaced by the guard column. Concentrating 10mL raw or treated water sample on to AGl6 guard column made it possible to get the LOD(Limit of Detection) of $0.73\;{\mu}g/L$. The total run time was 11 minutes and during run time next sample could be concentrated on AGl6 guard column. Compared to the Concentration method which needed manual operation, the Direct Injection method could screen the many water samples. The LOD of the Direct Injection method was higher and the sensitivity was lower than that of the Concentration method. The RSDs(Relative Standard Deviations) were lower than 2.5 % for peak height and 0.7 % for retention time in pre-concentration methods. This method Showed good reproducibility and reliability and it was thought the deviations of recovery value could be reduced by considering column capacity and making water sample homogeneous. Matrix Elimination could be done using the pre-concentration method if perchlorate were in complex matrix of sample.

• Journal of Korean Society of Water and Wastewater
• /
• v.32 no.5
• /
• pp.411-419
• /
• 2018

The residual chlorine concentration is an essential factor to secure reliable water quality in the water distribution systems. The chlorine concentration decays along the pipeline system and the main processes of the reaction can be divided into the bulk decay and the wall decay mechanisms. Using EPANET 2.0, it is possible to predict the chlorine decay through bulk decay and wall decay based on the pipeline geometry and the hydraulic analysis of the water distribution system. In this study, we tried to verify the predictability of EPANET 2.0 using data collected from experimental practices. We performed chlorine concentration measurement according to various Reynolds numbers in a pilot-scale water distribution system. The chlorine concentration was predicted using both bulk decay model and wall decay model. As a result of the comparison between experimental data and simulated data, the performance of the limited $1^{st}$-order model was found to the best in the bulk decay model. The wall decay model simulated the initial decay well, but the overall chlorine decay cannot be properly predicted. Simulation also indicated that as the Reynolds number increased, the impact of the wall.

• Textile Coloration and Finishing
• /
• v.25 no.3
• /
• pp.181-193
• /
• 2013

The purpose of this study is to investigate dyeing properties and functionality of cotton and silk fabrics dyed with hot-water extract from Juniperus chinensis heartwood. Water-soluble dye of Juniperus chinensis heartwood extracted with distilled water was expressed YR color series. Dye uptake of cotton continued to increase according to the increase of the dye concentration. Its variation trends were shown to be similar to the isothermal absorption curve of the Freundlich. Dye uptake of silk was better than cotton, increased depending on increasing concentration of the dye, dyeing time and temperature. Its variation trends were shown to be similar to the isothermal absorption curve of the Langmuir. As the pH increased, the dye uptake of fabrics reduced and showed increased on red tinge. Colors of the dyed fabrics were various, depending on dye concentration and the mordant type and mordant concentration. Washing fastness, light fastness and perspiration fastness were not good. However, rubbing and dry cleaning fastness showed relatively good grade. Dyed fabrics of ultraviolet-cut ability and deodorant ability were improved. And dyed fabrics showed antimicrobial abilities of 99.9% against Staphylococcus aureus.

• Journal of Korean Society of Water and Wastewater
• /
• v.12 no.3
• /
• pp.41-47
• /
• 1998

Doam Lake is located around the pasture area and Yongpyung Resort. Because of the waste load of domestic animals, nutrient concentration of the stream is high. In this study, waste load of Doam Lake watershed is calculated, and QUAL2E model is applied to the upper part of the Songcheon to calculate the input boundary concentration of Doam Lake. And WASP5 model is applied for the water quality modeling of Doam lake. The results indicate that advanced treatment of domestic animal wastes is necessary for the lake water quality management.

• Journal of Korean Society for Atmospheric Environment
• /
• v.20 no.6
• /
• pp.803-810
• /
• 2004

Water contents in fine particles at Seoul and Gosan are estimated by using a gas/particle equilibrium model, SCAPE (Simulating Composition of Atmospheric Particles at Equilibrium). Also, sensitivity of particulate inorganic ionic concentrations on the total ionic species is estimated. Water content at Gosan is more sensitive to ambient relative humidity (RH) than Seoul. At both sites water content is most sensitive to sulfate concentration among sulfate, nitrate, and ammonium. Solid salts levels and compositions are also studied.

• Journal of Korean Society on Water Environment
• /
• v.28 no.5
• /
• pp.754-761
• /
• 2012

Several drinking water treatment plants (DWTPs) produce the bottled tap waters (BTWs) as pilot production and provide them for noncommercial use. In 2008, acetaldehyde and chloral hydrate were detected in some BTWs and the public worry over the safety of the water. In this study, the BTWs produced from 7 DWTPs were tested for 13 chemicals including disinfection byproducts (DBPs). The level of four trihalomethanes (THMs) were increased up to 15 days. The average concentration of them was 0.0075 mg/L at the time of bottling and it was increased to 0.0214 mg/L after 15 days. The average acetaldehyde concentration was 0.0406 mg/L at the time of bottling but it was went up to 0.2251 mg/L after 11 days and then decreased. Although the initial concentrations of DBPs were below the drinking water standard, we also traced them at different storage conditions. Temperature affected the formations of THMs and acetaldehyde concentrations significantly. While the average concentration of THMs ranged from 0.0113 to 0.0182 mg/L at $25^{\circ}C$, it was increased to 0.0132 ~ 0.0256 mg/L at $50^{\circ}C$. In case of acetaldehyde, concentration ranged from 0.0901 to 0.2251 mg/L at $25^{\circ}C$, it was increased to 0.3394 ~ 1.0591 mg/L at $50^{\circ}C$. Throughout the tests with 7 BTWs samples, none of the chemicals was exceeded the drinking water standard of Korea. Therefore, it is recommended to avoid the exposure of BTWs to sunlight or high temperature during distribution and storage.

• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.1
• /
• pp.15-20
• /
• 2009

The concentration of residual chlorine should be kept at over 0.1 mg/L in the circular water tank used in a water purification system. Generally, the concentration of residual chlorine depends on the structure and the volume of water tank, and also the water flow rate. To secure the diffusion time is important to the concentration of residual chlorine. For that reason, the baffles are installed in the circular water tank. In the present study, the variations of water and chlorine concentration were obtained with time using the numerical analysis. And also, the streamlines were shown according to the number of baffles. As a results, the vortex flow appeared between baffles, and the diffusion time of chlorine increased with the more number of baffles.