• 한국물환경학회지
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• 제27권2호
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• pp.188-193
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• 2011

The effects of coagulants on the microorganisms when they are injected directly into the biological treatment facility for T-P removal have been easily observed from the results of past experiments. As such this study is set out to derive the effective plans for the coagulant dosage by analyzing the effects of the injected coagulant on the microbial activity during the chemical treatment for T-P removal. The research methods entailed the assessment of removal efficiency of T-P according to the coagulant dosage while changing the molar ration between Alum and influent phosphorus. At the same time Specific Oxygen Uptake Rate (SOUR) according to the coagulant dosage was measured. SOUR was used as a method for indirect assessment of the microbial activity according to the coagulant dosage. The results from the study showed that with the increase in the alum dosage, the removal efficiency T-P tended to increase. On the other hand, the increase in coagulant dosage resulted in the decrease in SOUR, which indicates the decrease in the microbial activity. Such reduction in the activity could be explained by the increase in the concentration of removal efficiency of $TBOD_5$. Based on experiment results from the study, it is determined that coagulant dosage affects the microbial activity. Moreover, the indirect assessment on the microbial activity using SOUR is considered possible.

• 환경위생공학
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• 제15권1호
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• pp.7-13
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• 2000

To develop the removal technique of algal bloom the efficiencies of algal flocculation/ autoflotation by the kinds of coagulant and oversaturated oxygen concentration were investigated. The summarized results are as follow. 1. In the algae flocculation test with alum[$Al_2(SO_4)_3{\cdot}18H_2O$], optimum pH was 5.5 and, with chitosan optimum pH was 7.0. 2. Chitosan which was natural polymer showed the 5~10 times higher algal biomass flocculation efficiency than alum in the condition of same algal concentration. 3. For the each coagulant, the higher ${\Delta}DO$(oversaturated dissolved oxygen concentration - saturated dissolved oxygen) was, the faster the rising velocity of the algal floc was. 4. In the condition of about 4mg/L ${\Delta}DO$, the rising velocity of chitosan is about 2 times higher than that of alum, and chitosan formed the stronger algal floc.

• 펄프종이기술
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• 제30권2호
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• pp.24-29
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• 1998

This study was carried out in order to elucidate the deterioration mechanism of paper according to various sizing chemicals. No additive paper and four kinds of papers containing rosin-alum, alum only, alkylketene dimer(AKD)-cation polymer and cation polymer only were treated by UV light to study changes of water-resistant, optical and mechanical properties from the view points of natural deterioration of paper. Since rosin chemicals have UV absorption at the relatively long wavelength region, rosins are degraded to form hydrophilic groups such as carboxylic acid from their double bonds by UV treatments. These phenomena caused the decreasing of sizing degree and wetting time in case of rosin-sized paper, while the UV treatments brought about the slight increase of wetting time in rosin-free papers such as no additive, alum and kymene only paper owing to the auto-sizing effect. Optical properties were primarily influenced by sizing chemicals. Rosin-sized paper showed lower brightness after UV and near UV treatment because of its UV instability.

• Bulletin of the Korean Chemical Society
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• 제30권8호
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• pp.1711-1714
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• 2009

We have described an efficient synthesis of quino[2,3-b][1,5]benzoxazepine α-aminophosphonate derivatives by the nucleophilic addition of triethyl phosphite to substituted quino[2,3-b][1,5]benzoxazepines promoted by easily available, inexpensive and mild catalyst KAl(S$O_4)_2{\cdot}12H_2$O(alum). The reactions proceed smoothly at room temperature under solvent-free reaction conditions and providing high yield of product in very short reaction time.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.825-828
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• 2009

Alum $(KAl(SO_4)_2{\cdot}12H_2O)$ is an inexpensive, efficient, non‐toxic and mild catalyst for the synthesis of bis(indolyl)methanes by the reaction of 1H-indole with various aldehydes/ketones under the influence of ultrasound irradiation in solvent‐free condition. The remarkable advantages of this method are the simple experimental procedures, shorter reaction times, high yields of product and green aspects by avoiding toxic catalysts and solvents.

• 한국식품영양과학회지
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• 제28권3호
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• pp.559-565
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• 1999

This study investigated the effects of tangsuyuk batter ingredients on sensory. The optimal condition was evaluated by using RSM(response surface methodology). Five ingredients(wheat flour, corn starch, sodium bicarbonate, alum, water) were used as independent variables, coding 36 experimental trials. The resulting sensory scores(flavor, fracture, color, overall acceptability) were used as dependent variables. Each dependent variable showed significant differences(p<0.05). When the amount of sodium bicarbonate was increased, the sensory scores for flavor and fracture also increased. Sensory scores for color also increased when the amount of sodium bicarbonate was increased and the amount of alum decreased. Overall acceptability scored higher when the amount of sodium bicarbonate was increased. This is therefore indicates that sodium bicarbonate is likely a very important ingredient in the batter. The effects of each ingredient on sensory were thus investigated. The optimum ratios of wheat flour, corn starch, sodium bicarbonate, alum and water were predicted to be 27.55%, 19.34%, 0.27%, 0.19% and 52.65% respectively.

• 한국가금학회지
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• 제31권4호
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• pp.221-228
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• 2004

본 연구에서는 두 화학제재($FeSO_4$와 Alum)를 처리한 영향이 깔짚 위에서 육계를 42일간 사육한 후 깔짚내 질소와 수용성 인 함량에 어떤 차이가 있는지 대조구와 비교시험을 하였다. 2가지 실험은 처리구에서 깔짚 kg당 화학제재를 $FeSO_4$ $7H_2O$ 200 g이나 $Al_2(SO_4)_3$ $\cdot$ $14H_2O$ 200 g을 top dressing 한 후 그 각각을 대조구와 비교하였다. 사양시험에서는 총 64수(4처리$\times$4반복$\times$4수)의 육계를 배치하였다. 두 화학제재 처리구($FeSO_4$와 Alum)는 두 대조구와 비교할 때 pH는 통계적 유의성이 없었지만, 수용성 인 함량은 고도의 유의성이 인정되었다(P<0.01). 두 화학제재 처리구($FeSO_4$와 Alum)의 SRP 함량은 대조구 각각보다 $79\%$와 $60\%$의 감소를 보였다 $FeSO_4$ 처리구와 대조구간에는 EC, TC, $NH_4$-N, $NO_3$-N 및 IN 함량은 유의성이 없었지만, 수분, TN, ON, AN, PAN C:N 및 C:ON은 통계적 유의성이 인정되었다(P<0.01). Alum 처리구와 대조구의 결과는 EC, $NO_3$,-N, ON 및 C:ON을 제외한 수분, TC, TN, $NH_4$-N, IN, AN, PAN 및 C:N은 통계적 유의성이 인정되었다(P<0.05와0.01). 본 연구 결과를 다시 종합하면 깔짚에 두 화학제재를 각각 처리할 경우 깔짚내의 질소 함량은 높았으며 SRP함량을 감소시켰다.

• 상하수도학회지
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• 제31권1호
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• pp.103-114
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• 2017

A membrane bioreactor by sequentially alternating the inflow and by applying a two-stage coagulation control based on pre-coagulation was evaluated in terms of phosphorus removal efficiency and cost-savings. The MBR consisted of two identical alternative reaction tanks, followed by aerobic, anoxic and membrane tanks, where the wastewater and the internal return sludge alternatively flowed into each alternative reaction tank at every 2 hours. In the batch-operated alternative reaction tank, the initial concentration of nitrate rapidly decreased from 2.3 to 0.4 mg/L for only 20 minutes after stopping the inflow, followed by substantial release of phosphorus up to 4 mg/L under anaerobic condition. Jar test showed that the minimum alum doses to reduce the initial $PO_4$-P below 0.2 mg/L were 2 and 9 mol-Al/mol-P in the wastewater and the activated sludge from the membrane tank, respectively. It implies that a pre-coagulation in influent is more cost-efficient for phosphorus removal than the coagulation in the bioreactor. On the result of NUR test, there were little difference in terms of denitrification rate and contents of readily biodegradable COD between raw wastewater and pre-coagulated wastewater. When adding alum into the aerobic tank, alum doses above 26 mg/L as $Al_2O_3$ caused inhibitory effects on ammonia oxidation. Using the two-stage coagulation control based on pre-coagulation, the P concentration in the MBR effluent was kept below 0.2 mg/L with the alum of 2.7 mg/L as $Al_2O_3$, which was much lower than 5.1~7.4 mg/L as $Al_2O_3$ required for typical wastewater treatment plants. During the long-term operation of MBR, there was no change of the TMP increase rate before and after alum addition.

• 대한환경공학회지
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• 제27권6호
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• pp.581-589
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• 2005

최근, 하 폐수 처리에 있어서 처리수의 보다 나은 수질과 엄격한 기준의 만족을 위해 기존의 공정외에 덧붙여 막분리 공정이 이용되고 있다. 그러나, 수처리 과정에서 막분리 공정의 사용은 막의 막힘 현상과 용존 유기오염물 제거의 어려움 등의 문제점이 있다. 본 연구에서는 막분리 공정에 응집제 alum과 PAC을 이용한 응집공정을 첨가하여 막 투과유속과 처리효율을 증가시켰다. 그리고 응집제 주입효과와 최적운전조건은 투과유속, 누적부피, 막의 총저항, 입자크기, 용존성 유기오염물, 용존성 알루미늄, 처리수의 수질을 분석하여 연구하였다. alum 응집에 비교해 PAC 응집은 큰 입자를 형성하여 여과 매체의 막힘현상을 줄이고 높은 투과유속과 누적 부피량을 보였다. 또한 PAC 응집에서 낮은 용존 유기오염물과 용존성 알루미늄은 투과유속 감소율을 낮추었다. $0.2\;{\mu}m$ 막 사용시 케이크여과의 모습을 보였으며, $0.45\;{\mu}m$ 막 사용시 순환운전으로 인한 플럭 깨짐 현상으로 공극보다 작은 플럭의 투과가 발생하여 투과유속이 계속 감소하고 막의 총저항이 증가하는 모습을 보였다. PAC과 alum 모두 약 $300{\pm}50\;mg/L$가 최적 응집주입량이었으며, PAC 응집과 $0.2\;{\mu}m$ 막 사용시 처리 효율이 가장 높고, $0.45\;{\mu}m$ 막 사용시 투과수량이 가장 많았다. 처리 효율은 탁도 99.8%, SS 99.9%, $BOD_5$ 94.4%, $COD_{Cr}$ 95.4%, T-N 54.3%, T-P 99.8%이었다.

• 대한환경공학회지
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• 제34권11호
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• pp.729-734
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• 2012

용존유기질소(DON)는 염소와 반응하여 인체에 유해한 질소계 소독부산물과 소독능을 저하시키는 유기성 클로라민을 생성할 수 있다. 이러한 물질의 생성을 줄이기 위해서는 소독공정 전에 DON의 제거가 필요하다. 본 연구는 DON을 함유하는 지표수와 재이용수를 이용하여 응집실험을 하고 알루미늄염(alum)과 고분자응집제(polyDADMAC)에 의한 DON의 제거특성을 조사하였다. 또한 DON, 용존유기탄소(DOC), 254 nm 자외선 흡광물질($UVA_{254}$)의 제거율 및 제거 기작을 비교하였다. 지표수와 재이용수 모두 alum 응집제의 주입농도를 증가시킴에 따라 DON, DOC, $UVA_{254}$ 제거율이 점진적으로 증가하였는데, 원수특성과 상관없이 소수성 유기물을 나타내는 척도인 $UVA_{254}$의 제거율이 가장 높았다. 지표수와 재이용수 모두 alum 응집제만 주입한 경우보다 고분자응집제를 같이 주입한 경우 DON의 제거율이 높게 나타났다. 고분자응집제의 전하중화가 작용하는 적정농도범위가 좁아 고분자응집제만 주입하기 보다는 무기응집제와 같이 주입하는 하는 것이 바람직하다. 상대적으로 생성된 후 오랜 시간이 지나지 않은 재이용수의 DON 제거율이 지표수의 DON 제거율보다 높았고, 지표수와 재이용수 모두 10,000 Da 이상 분자량의 DON 제거율이 높게 나타났다.