The waterborne perfluoroacylic polyurethane composite (WFPUC) series were prepared by the emulsion polymerization (WFPUC-E) and the physical blending (WFPUC-B). WFPUC-E was prepared by polymerizing perfluoroalkyl ethyl acrylate (FA) and waterborne polyurethane (WPU), and WFPUC-B was prepared by blending FA copolymer and WPU. The structures of the synthesized WFPUC were identified by using FT-IR-ATR. The surface and thermal properties of the synthesized WFPUC were investigated by measuring contact angle, surface energy, and TGA. The surface energy of WFPUC-E was lower than that of WFPUC-B. The thermal stability of the WFPUC-B showed better than that of the WFPUC-E.
For the purpose of development of an environmentally friendly aqueous cleanser, some experimental researches on emulsification of D-limonene were performed. OA series surfactants with different molecular weight were adapted as an emulsifier for preparation of O/W emulsion. Cleaning power of aqueous cleanser was measured by a dipping method adapting abietic acid(AA) as a solubilizate. Besides, drop size and drop size distribution, contact angle and storage stability of the aqueous cleansers were also measured and relationships among them were examined. Decrease in molecular weight of surfactant induced small drop size and contact angle, resulting in high cleaning power of aqueous cleanser. Aqueous cleanser consisted of 3wt.% OA300 and 30wt.% D-limonene showed the highest cleaning power, but displayed unfortunately with low storage stability. The storage stability of the aqueous cleanser with OA300 was significantly enhanced by addition of 0.5wt.% OA600 at the expanse of decrease in cleaning power.
The flora of vascular plants in Jangsanbong located at Busan Metropolitan City was investigated from April 2003 to April 2004. Vascular plants in the surveyed area were 254 taxa that belonged to 78 families, 175 genera, 218 species, 34 varieties, and 2 forma. Among them, 20 taxa of evergreen broad trees, 31 taxa of naturalized plants were identified, and especially Rubus trifidus was first recorded in Busan. In the upper part of a circular road dominant species was Pinus thunbergii. In the lower part of a circular road and the coastal area, dominant species were Platycarya strobilacea, Clerodendron trichotomum, Euscaphis japonica, Quercus aliena, Quercus dentata, Mallotus japonicus, which distribute mainly in the subtropical and temperate zone. In the surveyed area, the canopy consistsed of tall trees, Pinus thunbergii, and the understratum were trees such as Eurya japonica, Ficus erecta, Ligustrum japonicum, Prunus sargentii, and Celtis sinensis var. japonica.
Waterborne polyurethane dispersions (WPUD) were prepared by poly(ethylene glycol) adipate as the polyester type, α,ω-hydroxyalkyl terminated polydimethylsiloxane (PDMS-diol) as the polysiloxane type, hexamethylene diisocyanate, and isophorone diisocyanate, dimethylol propionic acid. The effects of PDMS-diol contents on the particle size, thermal and surface properties of WPUD were investigated. The structures of the synthesized WPUD were confirmed using by FT-IR. The surface, thermal and mechanical properties were investigated by measuring the contact angles, DSC, TGA and UTM. As PDMS-diol contents increased, the particle size, the contact angle, and the elongation was increased, while the tensile strength was decreased. Also the thermal stabilities of the synthesised WPUD were increased as PDMS-diol contents increased.
Effect of seawater temperature (temperature) on the production of anchovy, Engraulis japonica and laver, Porphyra tenera Kjellman, were investigated in the eastern part of South Sea of Korea (ESS). Bimonthly temperature data (Feb., Apr., Jun., Aug., Oct., Dec.) from 1980 to 2002 were collected from Korean Oceanographic Data Center (KODC) and monthly anchovy catch and laver production from 1980 to 2002 were used from published sources by the Ministry of Maritime Affairs & Fisheries, Korea. Effects of temperature on the two organisms were examined in four cases. In case of lower anchovy catch and higher laver production (1993), temperature during main spawning season of anchovy was about 0.2-0.6℃ lower than normal condition, and temperature during seed collecting season of laver in Namhaedo, Kojedo went down below 22.0℃. In case of higher anchovy catch and higher laver production (1995), optimum temperature for catch was formed in main fishing ground, temperature for seed collection was lower than 22.0℃. In case of lower anchovy catch and lower laver production (1996), temperature for spawning and catch was about 0.6-1.6℃ lower than normal condition, and temperature during seed collection in nursery was about 0.5-1.0℃ higher than optimum temperature for seed collection. In case of higher anchovy catch and lower laver production (1998), temperature during main fishing and spawning season was about 1.0-1.8℃ higher than normal condition, and temperature during laver seed collection in nursery was 1.5℃ higher than optimum temperature for seed collection.
Ion exchange resin was used to remove silica ion at ultralow concentration. The effects of temperature, type of ion exchange resin and single/mixed-resin systems on removal efficiency were estimated. As temperature increased, the slope of concentration profile became stiff, and the equilibrium concentration was higher. In the single resin system, the removal of silica was continued up to 400 min, but the silica concentration was recovered to initial concentration after 400 min due to the effect of dissolved CO2. In the mixed-resin system it took about 600 min to reach equilibrium. Because of faster cation exchange reaction than anion exchange reaction, the effect of CO2 could be removed. Based on the experimental results carried out in the mixed-resin system, the selectivity coefficients of silica ion for each ion exchange resin were calculated at some specific temperatures. The temperature dependency of the selectivity coefficient was expressed by the equation of Kraus-Raridon type.
Hydrochloride acid salts of new N2O2 tetradentate ligands containing amine and phenol N,N'-bis(2-hydroxybenzyl)-o-phenylenediamine(H-BHP), N,N'-bis(5-bromo-2-hydroxybenzyl)-o-phenylenediamine(Br-BHP), N,N'-bis (5-chloro-2-hydroxybenzyl)-o-phenylene-diamine(Cl-BHP), N,N'-bis(5-methyl-2-hydroxybenzyl)-o-phenylene-diamine (Me-BHP) and N,N'-bis(5-methoxy-2-hydroxybenzyl)-o-phenylenediamine(MeO-BHP) were synthesized. The ligands were characterized by elemental analysis, mass and NMR spectroscopy. The elemental analysis showed that the ligands were isolated as dihydrochloride salt. The potentiometry study revealed that the proton dissociation constants(logKnH) of ligands and stability constants (logKML) of transition and heavy metals complexes. The order of the stability constants of each metal ions for ligands was Br-BHP < Cl-BHP < H-BHP < MeO-BHP < Me-BHP.
The objective of this work is the air quality modeling according to the scenarios of emission on complex terrain. The prognostic meteorological fields and air quality field over complex areas of Seoul, Korea are generated by the PSU/NCAR mesoscale model (MM5) and the Third Generation Community Multi-scale Air Quality Modeling System (Models - 3/CMAQ), respectively. The emission source was driven from the Clean Air Policy Support System of the Korea National institute of Environmental Research (CAPSS), which is a 1 km x 1 km grid in South Korea during 2003.
In comparison of air quality fields, the simulated averaged PM10, NO2, and O3 concentration on complex terrain in control case were decreased as compared with base case. Particularly PM10 revealed most substantial localized differences by (18 ~ 24 μg/m3). The reduction rate of PM10, NO2, and O3 is respectively 18.88, 13.34 and 4.17%.
Red mud is a waste generated by the aluminium industry, and its disposal is a major problem for this industry. Red mud has a reddish-brown color and superfine particle characteristics. So, it can be a promising pigment admixture for concrete industry. An experimental study was conducted to investigate the potential use of red mud in color concrete. The micro structures of red mud and iron oxide pigment such as porosity, pore size distribution, diameter of particle were analyzed with the aid of SEM, X-ray diffraction(XRD), and the infrared absorbance. Tests on physical properties of color concrete, such as strength, slump, early shrinkage crack patterns, and color characteristics were carried out and the results were reported in this paper.
이 연구는 남해안 중부해역의 여름철 전 후 단계를 나누어서 6월부터 10월까지의 2004-2006년 장기간 해양환경 모니터링 및 식물플랑크톤 군집구조를 파악함과 아울러, Cochlodinium 적조발생에 관한 해석에 이용되고자 하는 것이다. 조사해역은 득량만, 고흥연안, 여자만, 가막만, 광양만, 여수연안, 남해연안으로 총 16개 정점이다. 수온은 19−29℃ 범위로 여름철 여자만에서 두 정점 모두 가장 높은 29℃C, 27℃
를 나타내었다. 그러나 8월을 제외한 6월, 7월, 9월, 10월에는 조사정점에 관계없이 큰 차이를 보여주지 않았다. 염분도는 7월과 8월에 여자만과 광양만에서 다른 조사해역에 비하여 약 5-6 정도 낮은 25-27를 나타내었다. 클로로필의 경우도 7월과 8월에 각 조사해역별 큰 차이를 보이고 있다. 특히 광양만은 최고 5배 정도 많은 15μgl−1 까지 보였다. 투명도는 수온, 염분도, 클로로필과 다르게 조사기간 동안 해역에 관계없이 거의 비슷한 수준인 2-5m 정도로 보여주고 있다. 용존무기질소도 조사해역 중 광양만의 경우 7월과 8월에 가장 높은 0.53mgl−1 까지 보여 10배 정도까지 차이를 보였으나, 용존무기인 상대적으로 큰 차이를 나타내지 못하고 있다. 용존무기질소와 클로로필의 관계를 보면 7월에는 임의 상관성을 보여 클로로필의 증가에 따른 용존무기질소가 급속히 소모됨을 알 수 있지만, 8월에는 거의 오히려 양의 상관성을 보여주고 있다. 식물플랑크톤의 평균 세포수는 7월과 8월에 500 cells ml−1 까지 나타내었고, 대부분 규조류의 비율이 60% 이상 출현되었으나, 8월에 와편모조류의 점유율이 20-30%까지 보였다. 우점종으로는 Skeletonema costatum이 2004년부터 2006년까지 전 해역에 걸쳐 가장 많이 출현되었다. 각 해역별에 출현하는 식물 플라크톤의 집괴분석에 따르면 상호 혼잡되어 분포 되는 것으로 나타났다. 이상의 결과를 보면 여름철에 가장 큰 해양환경 변화를 보였고, 식물플랑크톤 중 S. costatum은 남해연안의 대표적인 기초생산 종으로 간주된다. 특히 여름철 Cochlodinium 적조는 득량, 가막, 고흥, 여수, 남해해역에서 3년 동안 계속해서 발생된 반면, 여자만과 광양만은 전혀 나타나지 않았다. 뚜렷한 차이점은 용존무기질소 Cochlodinium 적조 형성을 위한 요구량은 수중에 풍부하게 존재하고 있기보다는, 미량이라도 충분히 적조를 유발시키고, 외해역에서도 발생될 수 있다는 뒷받침을 하고 있다.
The three-dimensional eco-hydrodynamic model was applied to estimate the autochthonous COD caused by production of phytoplankton in Jinhae Bay. A residual current was simulated, using a hydrodynamic model, to have a sightly complicated pattern in the inner part of the bay, ranging from 0.001 to 5 cm/s. In the outer part of the bay, the simulated current flowed out to the south sea with a southward flow at a maximum of 25 cm/s. The results of the ecological model simulation of COD levels showed high concentrations, exceeding 4 mg/L, in the inner bay of Masan, an area of wastewater discharge, and lower levels, approaching less than 1 mg/L, closer to the outer part of the bay. The simulation results of Autochthonous COD by two methods using ecological modeling, showed high ratio over 70% of total COD. Therefore, it is more important to consider nutrients than organic matters in the region for control COD standard.
The eco-hydrologic effects of maintenance water supply on Oncheon stream are studied using hydrologic, hydraulic and ecologic models. SWMM (Storm Water Management Model) is used for long-term simulation of runoff quantity and water quality from Oncheon stream watershed. Using the output hydrologic variables from SWMM, HEC-RAS (River Analysis System) is then used to simulate the hydraulics of water flow through Oncheon stream channels. Such hydrologic, hydraulic and water quality output variables from SWMM and HEC-RAS are served as input data to execute PHABSIM (Physical Habitat Simulation) for the purpose of predicting the micro-habitat conditions in rivers as a function of stream flow and the relative suitability of those conditions to aquatic life. It is observed from the PHABSIM results that the weighted usable area for target fishes has the maximum value at 2 ㎥/s of instream flow. However, mid and down stream areas that have concrete river bed and covered region are unsuitable for fish habitat regardless of instream flow increment. The simulation results indicate that the simple maintenance water supply is limited in its effect to improve the ecological environment in Oncheon stream. Therefore, it is imperative to improve water quality and to recover habitat conditions simultaneously.
To investigate the effect of NOx and VOCs(volatile organic compounds) on the generation of high ozone episode, examined the hourly variations of ozone, NOx and VOCs concentrations, and calculated the ozone isopleth about maximum ozone concentrations using OZIPR which was presented by U. S. EPA at three sites in Busan. There was some difference by the sites, but decreasing VOCs concentration was effective for reduction of ozone at 22 July, the episode day of 2005. In the year 2006, the episode day was 8 August and the variations of NOx and VOCs concentration was little than variation of ozone. So it was estimated that the photochemical production of ozone was low than transportation of ozone. And the result of the OZIPR modeling was that decreasing VOCs concentration was effective for reduction of ozone.
This study assessed the characteristics of emission and cell toxicology of Methylethylketone(MEK) in ambient air of industrial area. MEK is produced by the oxidation of sec-butyl alcohol and used as the solvent for making ink, printing, coating of film, bonding material and drug extraction. The MEK concentrations in the ambient-air of industrial area in Gimhae City was detected in the range of 25.4~1,580 ㎍/㎥ with an average 297.4 ㎍/㎥. The concentration of MEK showed a descending tendency from April to August followed by its increased tendency since then. The effects of MEK on the human lung cancer A549 cells was examined by the generation of Reactive Oxygen Species(ROS) and cytotoxicity. The range of MEK concentration detected in the area induced ROS generation affecting the oxidation state with a little effects on the viability of the cells.
Passive sampler is a simple and cost-effective measuring equipment for ambient and indoor air pollution. We studied the performance of a short term (1 hour mean concentration) ozone passive sampler which was coated with a colorant (indigo carmine) to a filter substrate. Acetone and sulfamic acid added ozone passive sampler was investigated to measure short term mean ozone concentration. Ozone response and interference of criteria air pollutant(SO2, NO2, CO) on a short term ozone passive sampler was tested through experimental chamber. The results show sulfamic acid added passive ozone sampler have good response in ozone exposure. Interference of NO2 gas is larger than other two criteria gases.