• Journal of Environmental Science International
• /
• v.16 no.7
• /
• pp.805-811
• /
• 2007

The purpose of this study was to invesitigate relationship between rainfall water quality and precipitation characteristic during the accumulated rainfall and rainless period. As the results of the analysis, rainfall water quality was improved in the rainfall duration. Correlation coefficients between rainwater quality and accumulated rainfall were $0.88{\sim}0.99$ except $Cl^-$. and that between rainless period and initial rainfall water quality were $0.62{\sim}0.75$. During the Asian dust event, concentration of the turbidity, BOD and electric conductivity were high. Therefore, it shows that the rainfall water quality is effected by atmospheric conditions before the rainfall events.

• Journal of Environmental Health Sciences
• /
• v.35 no.1
• /
• pp.58-63
• /
• 2009

This study investigated improvement to sludge dewaterability and coagulation for sewage treatment plant sludge by using sodium hypochlorite solution (NaOCl), ferric sulfate [$Fe_2(SO_4)_3$] and zeolite. The specific resistance to filtration(SRF), chloride, pH and turbidity were used to evaluate the sludge dewatering behaviors. The results of study were as follows: By varying the amount of NaOCl added the optimum result in terms of enhancement for pretreatment occurred when 34 mg/l of NaOCl was injected. When the total solids concentration of the sludge was 10,000 mg/l, the optimum ferric sulfate dosage for the sludge dewaterability was 150 mg/l and the corresponding SRF was $1.7{\times}10^7sec^2/g$. It was observed that injecting zeolite into sludge was effective in improving the dewaterability of sludge.

• Proceedings of the SCSK Conference
• /
• 2003.09b
• /
• pp.379-391
• /
• 2003

Nanoemulsions have many specific characters compared with general emulsions in aspect of stability, rheological property, uniformity, high interfacial tension and so on. Therefore we study on nanoemulsions with changing various lecithins and oils using microfluidizer. As lecithins, we used saturated lecithin, unsaturated lecithin and hydrogenated phosphatidylcholine. Caprylic capric triglyceride, Squalane, Macadamia nut oil, Liquid paraffins, Dimethicone, and Cyclomethicone were used as oils. To identify nanoemulsions, we measured paticle size, zeta potential, turbidity and transmission electron microscope.

• KSBB Journal
• /
• v.15 no.1
• /
• pp.96-99
• /
• 2000

Liposome-amino acid conjugates were prepared using phopholipid (dipalmitoylphosphatidylcholine (DPPC) or distearoylph-osphatidylcholine(DSPC)) and hydrophobically modified amino acids (glutamic acid(glu), glutamine(gln) or asparagine(asn)). The size of liposomes was about 100 nm. According to the glucose-induced turbidity changes, liposomes composed of DPPC and glutamic acid have higher glucose binding affinity than liposomes of DPPC-glutamine or DPPC-asparagine. Also, the liposomes were more stable in terms of aggregation or fusion than the others (DPPC-glutamine, DPPC-asparagine and DSPC-amino acids). As a rdsult, stable liposomes with an affinity for glucose could be prepared with DPPC and glutamic acid.

• Journal of the Korean Applied Science and Technology
• /
• v.25 no.2
• /
• pp.205-210
• /
• 2008

The transformation of the liquid crystal complex made by binding of anionic surfactant, sodium dodecyl sulfate (SDS), into high charge density cationic polymer, the homopolymer of diallyldimethylammonium chloride (PDADMAC) was induced by adding of nonionic surfactants and investigated by means of microscopy and FE.SEM. Among nonionic surfactants in this experiments polyethylene glycol (3 mol) ether of lauryl alcohol (laureth-3) made variation in the complex. The laureth-3 transformed the complex into spherulite vesicle with the size of ca.$100{\mu}m$. This change increased the viscosity and the turbidity of the solution phase separated originally. Microscope showed that they are spherulite particles and polarized microscope suggested they are multi.lamellar liquid crystals. FE-SEM also proved that explicitly.

• Journal of the Korean Society of Food Culture
• /
• v.34 no.1
• /
• pp.61-67
• /
• 2019

This study examined the quality characteristics of dumpling shells prepared with 0, 2, 4, 6, and 8% mulberry leaf powder. According to the amylograph data, the composite of mulberry leaf powder-wheat flour samples reduced the gelatinization temperatures, viscosities at $95^{\circ}C$, and maximum viscosity with increasing mulberry leaf powder content. The lightness (L) and redness (a) values decreased with increasing mulberry leaf powder content, whereas the yellowness (b) value increased. In addition, the weight, volume, and turbidity increased after cooking. In terms of the textural characteristics, addition of mulberry leaf powder increased the hardness, springiness, cohesiveness, chewiness, and adhesiveness. The DPPH free radical scavenging activity of the dumpling shells increased significantly (p<0.05) with increasing levels of mulberry leaf powder. The taste, chewiness and texture of the dumpling shells prepared with added 4% mulberry leaf powder were preferred. The sensory evaluation showed that the overall preference of the dumpling shell with the addition of 4% mulberry leaf powder was more effective than the control.

• Journal of the Korean Society for Precision Engineering
• /
• v.14 no.1
• /
• pp.101-107
• /
• 1997

Recently, as the raw water quality becomes to be polluted and the seasonal and local variation of water quality becomes to be severe, an exact control of coagulant dosing have been required in the water treat- ment plant. The amounts of coagulant is related to the raw water quality such as turbidity, alkalinity, water temperature, pH and edectrical conductivity. However the process of chemical reaction has not been clarified so far, so the dosing rate has been decided by jar-test, which is taken one or two hours. For the sake of this coagulant dosing control, fuzzy neural network to fuse fuzzy logic and neural network was proposed, and the scheme was applied to automatic determination of coagulant dosing rate. This controller can automatically identify the if-then rules and tune the membership functions by utilizing expert's cintrol data. It is shown that determination of coagulant dosing rate according to real time sensing of water quality is very effect.

• Journal of Korean Society of Water and Wastewater
• /
• v.28 no.4
• /
• pp.479-489
• /
• 2014

Membrane backwashing waste shows seasonally different characteristics and it has bad settleability differently from general backwashing waste in water treatment plant. When chemicals was injected to membrane backwashing waste, the settleability was better than chemicals was not injected. However, when settled lower sludge was not discharged, flowing sludge continuously was concentrated over a certain surface and floatation penomena occurred according to flowing velocity. When the lower sludge was discharged continuously in the thickener to prevent floatation penomena of turbidity materials, the depth of sludge surface was the least and the settleability increased.

• Journal of Environmental Science International
• /
• v.9 no.5
• /
• pp.369-374
• /
• 2000

The estuary of Nakdong river is very influenced by the freshwater contained nutrients and organic materials. The response results of these influences are eutrophication and red tide outbreak in this region. Concentration of chlorophyll a was 0.78~62.55$\mu\textrm{g}$/L in February 1.20~21.29$\mu\textrm{g}$/L in April 1.88~188.35$\mu\textrm{g}$/L in June and 0.78~11.21$\mu\textrm{g}$/L in August respectively. The decrease of chlorophyll a is considered that residence time is shorten by increase of freshwater discharge and unfavorable growth condition of phytoplankton is created by diffusion of low salinity and increase of turbidity. The phytoplankton maximum region located inner side of this estuary during winter season whereas it was moved to outer side when mean discharge of the Nakdong risver was increased, Therefore the variation of phytoplankton maximum region was affected by input discharge from the Nakdong river basin.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.38 no.4 s.117
• /
• pp.31-40
• /
• 2006

Presence of old newspapers printed with waterbased flexographic inks leads to a significant loss of brightness of the deinked pulp by flotation process. It has been shown that neutral or acidic flotation deinking has many advantages in recycling of flexo printed newsprints. A comparative experimental study was performed to evaluate the deinking efficiency of three alcohol type deinking agents in flotation deinking of flexo printed newspapers. Zeta potential of neutral deinked pulp was less negative than alkaline deinked pulp. Also neutral deinking was advantages in reducing turbidity, COD, and cationic de-mands of deinking process water.