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        검색결과 338

        302.
        2007.02 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        온수처리와 MAP에 의한 '후지' 사과의 저장 후 품질의 변화를 알아보기 위해 기존의 방법과 비교하여 18주 동안 중량감소율, 경도, 적정산도, 비타민 C 함량, 기호도 조사를 실시하였다. 그 결과 저장 18주후 중량 감소율은 대조구 22%, 포장구는 1% 이하의 중량 감소율을 보였으며, 온수처리에 의한 효과보다는 필름 포장으로 적은 중량 감소율이 나타났다. 경도는 초기값에 비해 대조구는 25 %, H-N구는 22%, C-MAP구는 10%, H-
        303.
        2007.01 KCI 등재 서비스 종료(열람 제한)
        The purpose of this work is to investigate the water quality change characteristics of treated water in water distribution systems of Water Treatment Plants (WTPs) of Jeju City. For this, the raw water, treated water and tap water that did not pass (named as not pass-tap water) and passed through the water storage tank (named as pass-tap water) were sampled and analyzed monthly from September 2001 to August 2002, for four (W, S, B and O) WTPs except for D WTP (where treated water is not supplied continuously) among WTPs of Jeju City. The concentrations of NO3- and Cl- of treated water in distribution systems changed little, but changed seasonally, which is considered to be based on the seasonal variation of the quality of raw water. The pH of treated water changed little in distribution systems for S WTP, but for the other WTPs, the pH of not pass-tap water was similar to that of treated water and the pH of pass-tap water was higher than that of treated water. The turbidity of treated water in distribution systems changed little except for W2 of W WTP and S4 and S5 of S WTP, where it was higher than that of each treated water. The residual chlorine concentrations between treated water and not pass-tap water changed little, but those between treated water and pass-tap water changed greatly, based on the its long residence time in water storage tank and so its reaction with organic matter, etc or its evaporation. The concentrations of TTHMs (total trihalomethanes) and CHCl3 that induce cancers in water distribution systems of these WTPs, were much lower than their water quality criteria and those in other cities. The concentrations of TTHMs of treated water and not pass-tap water were similar, but concentrations of pass-tap water were 1.5 to 2.0 times higher than those of treated water and not pass-tap water, due to the reaction of residual chlorine and organic matter, etc, with the result of long residence time in water storage tank.
        304.
        2006.12 KCI 등재 서비스 종료(열람 제한)
        This experiment was conducted on wild vegetables; Gondalbi (Cirsium setidens), Deoduck (Codonopsis lanceolata Trautv.), and Jandae (Adenophora triphylla var. Joponica Hara) seed to study whether priming with deep sea water results in enhancement of seed germination and identify the optimum concentration of the priming solution, and duration of priming. Seeds were primed with 5 various concentrations (5%, 10%, 15%, 20% and 30%) of deep sea water (DSW) in 12 hours, 24 hours, and 48 hours at 24℃. Since Jandae had seed dormancy, it was kept for four weeks in refrigerator at 2℃ after priming treatment. In Deoduck, 5 percentage DSW priming significantly improved the early germination percentage, radicle length, and plumule emergence percentage. Among the priming period of treatments, 24 hours priming showed better performance in this treatment whereas, in Jandae, 12 hours priming with 10 percentages DSW significantly improved the germination percentage and germination rate. This treatment had increased the final germination percentage by 54%, 15% and 40% compared with control, plain water and KNO3 priming respectively. But in Gondalbi, priming did not improve the germination of seed. However, among the priming treatments, 12 hours priming with 3% KNO3 and 20% DSW gave better performance. In both the wild vegetables; Deoduck and Jandae, priming in deep sea water had improved the germination percentage and germination rate as compare to plain water, KNO3, and without priming treatment. Hence the best seed priming treatment on Deoduck and Jandae are 24 hours with 5% DSW and 12 hours with 10% DSW respectively.
        305.
        2006.09 KCI 등재 서비스 종료(열람 제한)
        This research aims to investigate the behavior of organic matter that causes bacterial re-growth and the formation of disinfectant by-products such as THM in water treatment, and to optimize conditions for a more efficient and conventional water facility. THM removed 51 % and 12 % through coagulation/sedimentation and filtration using a selected conventional system. In this experiment, the removal ratio of DOC was highest at 68 % when the Gt value was 42,000 and lowest at 41 % when the Gt value was 30,000. 77-84 % of total DOC was removed during coagulation/sedimentation, and 15-23 % was removed during filtration. When Gt values were between 30,000 and 66,000, over 50 % of high molecular matter above 10 K during coagulation/sedimentation was removed. Turbidity removed 98 % when the Gt value was 66,000. As the Gt value increased, the turbidity removal ratio increased. Turbidity removed over 20 % during the filtration process.
        306.
        2006.04 KCI 등재 서비스 종료(열람 제한)
        선박에서 발생되는 밸러스트수를 전처리하기 위하여 수중에 포함되어 있는 입자상 오염물질과 수중생물체를 자동역세척 여과장치를 이용하여 처리한 결과를 나타내었다. 밸러스트수를 처리하기 위한 전처리의 장점은 입자상의 오염물질을 제거하여 후처리공정의 처리효과를 높이는데 있다. 여과필터의 회전속도가 20rpm에서는 여과압력이 40.5mmHg이고, 40rpm 에서는 36.6mmHg이며 60rpm 이상에서는 35mmHg로 나타나 연속적으로 여과할 수 있었다. 필터의 막힘현상으로 역세 회복압력과 역세간격은 시간의 경과에 따라 조금씩 감소하고 처리유량도 감소하는 것을 관찰할 수 있었다. 회분식 여과처리공정은 자동 역세척을 수행하는 공정에 비해서 처리효율의 저하가 일어났다. 여과 처리를 통하여 70μm이상의 식물성 플랑크톤과 동물성 플랑크톤을 포함하는 수중생물체를 제거할 수 있었다. 실험결과를 통하여 밸러스트수 처리에 적용 가능한 기술임을 알 수 있었다.
        307.
        2005.08 KCI 등재 서비스 종료(열람 제한)
        For the sustainable management of marine ecosystem in Masan Bay, we have to assess the carrying capacity and standard of target water quality. In this research, we assume that all pollutants loads are treated in Dukdong sewage treatment plant, then we simulate the physical-biological model for prediction water quality for the achievement of standard water quality. In 2001 year, for the achievement of COD 2.5 mg/L, we need to reduce COD 90 %, nitrogen 30 %, phosphate 90% than that of the present value. According to these results, the water quality of sewage treatment plant is required to treat COD 13.5 mg/L, nitrogen 33.3 mg/L, phosphate 6.0 mg/L. If the sewage treatment plant will be expanded much larger in 2011, it will need to be treated in COD 6.6 mg/L, nitrogen 2.5 mg/L, phosphate 5 mg/L for the achievement of water quality standard in COD 2.5 mg/L.
        308.
        2005.03 KCI 등재 서비스 종료(열람 제한)
        The performance of ozone contactor in ozone-BAC advanced water treatment process was evaluated by the degree of decomposition of organic matters. The degree was measured by the analyses of UV254 absorbance and the concentrations of DOC and BDOC for the sand filtered water and the ozone treated water, respectively. In addition, the ozone concentration in the contactor, required for the maximum BDOC concentration, was selected as the optimum concentration, and the appropriate residential time of ozone treated water in a reservoir was recommended based on the residual ozone concentration in the treated water. The following results were obtained from the pilot scale experiments. By ozonation UV254 absorbance was decreased, and BDOC concentration was increased. The change of DOC concentration by ozonation was negligible, but the excess input of ozone resulted in the removal of the small amount of BDOC by complete oxidation. The optimum ozone concentration was 0.58 mg O3/mg DOC. In order to remove residual ozone, 20 minutes of the residential time were enough after ozonation.
        309.
        2004.12 KCI 등재 서비스 종료(열람 제한)
        선박에서 발생되는 밸러스트수를 전처리하기 위하여 수중에 포함되어 있는 미생물을 복극전해처리시스템을 이용하여 살균처하였다. 전해처리시스템에 유입되는 시료는 정량펌프를 사용하여 상향류로 전극판 사이를 통과하도록 하였으며, 반응시간별로 유량을 조절하여 체류시간을 다르게 하였다. 양극판은 티타늄에 이산화이리듐을 전착한 Ti/Ir02 극판으로 하였으며, 음극판은 스테인리스 스틸판을 사용하였다. 전원공급은 최대 전압이 250V, 전류가 100Amper의 맥류가 전혀 없는 트랜지스트 평활회로를 사용한 D.C. Power Supply를 사용하여 전류밀도를 조절하여 운전하였다. 반응시간에 따라 전류밀도를 0.1~1.0A사이로 변화를 주어 실험한 결과 5초 이내에 E. coli, Bacteria, Bacillus sp.의 미생물이 사멸됨을 확인할 수 있었고, 전극간격은 75mm, 전류밀도 2.0A/dm2, 체류시간을 5초로 하였을 때 제거율이 90%이상이였다. 연구결과를 통하여 밸러스트수 처리에 적용 가능한 기술임을 알 수 있었다.
        310.
        2004.07 KCI 등재 서비스 종료(열람 제한)
        As the concentration of ammonium nitrogen could be reached 2~3 mg/L in the winter in the river. It was clear that the excessive concentration of chlorinated organics could be produced with the increase of chlorine addition to remove ammonium nitrogen. In the innovative ammonium nitrogen removal process, zeolite adsorption is very efficient as substitute for rapid sand filtration without other adverse quality change in the water. This study is conducted to evaluate the feasibility of ammonium nitrogen removal and regeneration by zeolite adsorption in drinking water treatment. Also, the reuse possibility of zeolite is evaluated to change the removal efficiency of ammonium nitrogen through several times of regeneration. The ammonium nitrogen was not removed in sand filter, but it was almost removed in zeolite filter during 7 days. The sand and zeolite filters have a similar result of turbidity removal. Therefore, zeolite filtration was confirmed the removal of turbidity and ammonium nitrogen as a media. When compared KCl with NaCl as a chemical for zeolite regeneration, it is demonstrated that KCl was more efficient than NaCl in the ability of zeolite regeneration. The adsorption rate of ammonium nitrogen was almost not decreased in the results of several times of regeneration. It is indicated that both zeolite and regeneration solution were possible to reuse without variation of regeneration rate through this study.
        311.
        2004.04 KCI 등재 서비스 종료(열람 제한)
        Waste water-soluble cutting oil was treated with W1 type #1 and W1 type #2. The properties of the original water-soluble cutting oil were pH=10.4, viscosity=1.4cP, CODcr=44,750 ppm, and TOC=10,569 ppm. However, the properties of the oil used for more than 3 months were changed to pH=7.82, viscosity=2.1cP, CODcr=151,000 ppm, and TOC=74,556 ppm. It might be attributed to the fact that molecular chains were cut due to thermal oxidation and impurities such as metal chips were incorporated in to the oil during the operation processes. To prevent the putrefaction of oil, the sterilization effect of ozone and UV on the microorganism in the oil was investigated. Ozone treatment showed that 99.99% of the microorganism was annihilated with 30 minutes contact time and 60 minutes were necessary for the same effect when UV was used. Ozone treatment could cut molecular chains of the oil due to strong sterilization power, which was evidenced by the increase of TOC from 25,132 ppm at instantaneous contact to 28,888 ppm at 30 minutes contact time. However, UV treatment didn't show severe changes in TOC values and thus, seemed to cause of severe cut of molecular chains. When the activated carbon was used to treat the waste water-soluble cutting oil, TOC decreased to 25,417 ppm with 0.1g carbon and to 15,946 ppm with 5.0g carbon. This results indicated that the waste oil of small molecular chains could be eliminated by adsorption. From the results, it could be concluded that these treatment techniques could be proposed to remove the waste oil of small molecular chains resulting in the degradation of the oil properties. In addition, these experimental results could be used for the correlation with future works such as investigation of the molecular distribution according to the sizes, lengths, and molecular weight of the chains.
        312.
        2004.01 KCI 등재 서비스 종료(열람 제한)
        The effect of ozone on the formation and the removal of disinfection byproducts(DBPs) of chlorination process was studied to elucidate the performance of water treatment process. The samples of raw water, prechlorination process, and preozonation process were analyzed quantitatively according to the Standard Methods for the Examination of drinking water. As a result, most of total trihalomethanes(THMs) which were formed in prechlorine treatment process was not removed in the preozonation process. Most of haloacetic acids(HAAs), haloacetonitriles(HANs), and chloral hydrate(CH) was removed in sedimentation and biological activated carbon(BAC) filtration processes. However, DBPs were increased more or less by postchlorine step. In particular, the formation of THMs and HAAs depends on ozone more than chlorine, but, the formation of HANs and CH depends on chlorine more than ozone. The seasonal variation of DBPs concentration for the year needs to be investigated to study the temperature effect because DBPs strongly depend on temperature among various efficient factors.
        313.
        2003.09 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        풋고추의 저장성 향상을 위한 저장전 열처리 조건을 구명하기 위하여 풋고추를 50, 55, 60, 의 온수에 각각 10초 침지하여 열처리를 하였다 에서 10초 열처리한 경우는 열처리 직후 과육표면에 가열장해 현상이 나타났다. 온수에서 침지한 풋고추를 1의 저장고에서 4주 동안 저장하면서 관능적 품질, 화학적 품질과 미생물학적 품질을 측정하였다. 표면 색도 중 L 값은 저장 중 조금씩 감소하는 경향을 보였으며, a 값과 b 값은 저장 3주까지는 거의
        314.
        2003.06 KCI 등재 서비스 종료(열람 제한)
        Soybeans [Glycine max (L.) Merr.] are frequently exposed to unfavorable environments during growing seasons and water is the most important factor limiting for the production system. The purpose of this study was to determine the leaf water potential changes by irrigation, and to evaluate the relationships of leaf water potential, growth and yield in soybeans. Three soybean cultivars, Hwangkeumkong, Shinpaldalkong 2, and Pungsannamulkong, were planted in growth chamber and field with irrigated treatments. Leaf water potential of three soybean cultivars was positively correlated with leaf water content during vegetative and reproductive growth stages in growth chamber and field experiments. Leaf water potentials measured for three soybean cultivars under growth chamber were higher than those of under field conditions. Higher leaf water potential with irrigated plots under field was observed compared to conventional plots during reproductive growth stages. Leaf water potentials of three soybean cultivars were continually decreased during reproductive growth stages under field and there was no significant difference among them. Number of leaves, leaf water content, pod dry weight, number of seeds and seed dry weight with irrigated plots were higher than those of conventional plots. The results of this study suggested that leaf water potential could be used as an important growth indicator during the growing season of soybean plants.
        315.
        2003.03 KCI 등재 서비스 종료(열람 제한)
        This study was conducted to evaluate the feasibility of ammonia removal by zeolite adsorption in drinking water treatment. In generally, drinking water treatment process is conducted coagulation/flocculation, sedimentation, sand filtration and disinfection. We tested feasibility with two method, one is powdered zeolite dosing to coagulation tank and the other is to substitute granular zeolite for sand of sand filter. In powdered zeolite test, raw water is used tap water with putting of 2mg/l of NH4+-N. Filtration of granular zeolite was conducted with 80cm of effective column high and 120m/d of flow rate. At above 100mg/l of zeolite dosage, ammonia concentration was decreased below 0.5mg/l of NH4+-N in powdered zeolite test. But, turbidity was increased to 30NTU by powdered zeolite dosage. That turbidity was scarcely decreased in generally coagulant using condition in drinking water treatment. In granular zeolite test, ammonia was not detected in treated water until 8 days. This result suggest that using of granular zeolite in sand filter could be removal ammonia in winter. But we need regeneration at zeolite filtration for ammonia removal. So, it is to make clear that zeolite regeneration ability was compared KCl with NaCl. The result reveal that KCl was more excellent than NaCl. Optimum regeneration concentration of KCl was revealed 100 mM. Regeneration efficient was not increased at pH range 10~12.5
        316.
        2003.03 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        제주산 하우스 감귤의 유통전 처리에 따른 선도변화를 분석한 결과, 유통 중 가용성고형물은 온도조건이나 처리방법에 따라 큰 차이가 없이 거의 일정하게 유지되었다. 산 함량 및 경도는 유통초기에 비해 전체적으로 감소되었으나 저온유통처리구가 상온유통처리구에 비해 높게 유지되었고 상온과 저온유통 조건에서 모두 전해산화수 및 왁스코팅 처리가 대조구보다 높게 유지되었다. 과실 내부의 초기 발생량은 1% 내외였지만 상온유통조건에서는 기간이 경과됨에 따라 증가
        317.
        2002.12 KCI 등재 서비스 종료(열람 제한)
        This study was carried out to evaluate the pollutant removal efficiencies of the advanced drinking water treatment using ozonation process. For raw water, Nakdong River was used. By conducting batch test of ozonation, the following results were obtained. When ozone dosage of 5 mg/ℓ was used, ozone transfer and utilization efficiencies of the ozonation were 94 to 92%, respectively. Removal efficiencies of single VOC compound or mixed VOC compounds in the raw water were 80% to 90% by the ozonation with 2 mg/ℓ dosage and 10 minutes contact time. Removal efficiencies of ABS by the ozonation with 1 mg/ℓ, 3 mg/ℓ dosage and 20 minutes contact time were 83% to 96% , respectively. Almost 67% of chlorophyll-a at the concentration of 38.4㎍/ℓ was removed by ozonation at ozone dosage of 1 ㎎/ℓ for 20 min. Considering the efficiency of ozone utilization and water treatment, the most effective ozonation could be obtained with high ozone dosage and short contact time.
        318.
        2002.12 KCI 등재 서비스 종료(열람 제한)
        본 연구는 염수 농도, 처리기간 및 처리시기가 벼의 생육 및 수량에 미치는 영향을 검토하고자 한 것이다. 처리시기는 분얼기, 감수분열초기, 출수기였으며, 염수처리 농도는 고농도(3.0%), 중농도(1.5%) 및 저농도(0.5%)로 하여, 고농도와 중농도는 4일간, 저농도는 30일간 처리하였다. 공시품종은 장안벼로 하여 시험을 수행한 결과를 요약하던 다음과 같다. 1. 잎 피해율은 처리시기에 관계없이 고농도 단기처리에서 가장 심하였으며, 1999년에는 분얼기, 출수기, 감수분열초기 순으로 및 피해율이 높았으나, 2000년도에는 출수기, 감수분열초기 , 분얼기 순이었다. 2. 출수기는 분얼기 염수처리에서 1-5일 지연되었다. 간장 및 수장의 단축은 감수분열초기에 염수를 처리하였을 때 가장 심하였다. 3. 감수분열초기 염수처리에서 수량감소가 가장 켰고, 다음이 출수기, 분얼기 순이었으며, 이삭수를 제외한 수량 및 수량 구성요소에서 무처리>중농도 단기처리>저농도 장기처리>고농도 단기처리 순으로 낮게 나타났다 수량구성요소중 등숙률과 천립중이 염수처리에 의한 감소가 가장 현저하였다. 4. 감수분열초기 염수처리에서 다른 생육시기에 비해 많은 지발이삭의 발생으로 이삭수가 많았으며, 지발이삭에 의한 수량 보상력은 2.1-12.0%이었다. 5. 립중, 등숙속도 및 등숙기간에 대하여 분얼기 처리에서는 처리농도 및 처리기간별로 차이가 크지 않았으며, 감수분열초기 처리에서는 저농도 장기처리 및 고농도 단기처리에서, 출수기 처리에서는 고농도 단기처리에서 크게 감소하였다.
        319.
        2002.04 KCI 등재 서비스 종료(열람 제한)
        This study was to analyze the right or wrong of gray-water treatment by applying BPBE electrode cell to the effluence water in the terminal disposal plant of sewage. The results were as follows : The best result was obtained with applied voltage 40V and detention time 6 minutes for the BPBE electrode cell which has the graphite-plate in main electro-de, packing coconut activated carbon. The elimination rate of COD of Al-plate was higher than that of graphite-plate in main electrode. The result of electrolysis for 3 hour in parallel circuit showed the using possibility of gray-water according to each elimination rate : COD 59%, T-N 69 %, T-P 69%. The BPBE electrode cell with the Al-plate in main electrode made the best effect for the elimination of algae in lake water and algae were not occurred in electrolytic water
        320.
        2001.12 KCI 등재 서비스 종료(열람 제한)
        This study was carried out to evaluate the pollutant removal efficiencies of the advanced drinking water treatment using ozonation. For raw water, Nakdong River was used. By conducting batch ozonation test, the following results were obtained. When ozone dosage of 5㎎/ℓ was used, preozonation of raw water reduced turbidity, KMnO4 consumption, DOC(dissolved organic carbon), UV254 absorbance, THMFP(trihalomethane formation potential) as much as 3.9 NTU, 5.5㎎/ℓ, 1.15㎎/ℓ, 0.112 and 0.065㎎/ℓ, respectively. In case of postozonation of sand filtered water, water quality was also improved with decrease in turbidity, KMnO4 consumption, DOC, UV254 absorbance and THMFP at the amount of 0.08NTU, 2.6㎎/ℓ, 0.88㎎/ℓ, 0.042 and 0.018㎎/ℓ, respectively. On the other hand, contents of dissolved oxygen increased at the level of 1.3㎎/ℓ after preozonation process' and 1.0㎎/ℓ after postozonation process. The effect of ozone dosage was higher than that of its contact time for the removal of the pollutants.
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