• Environmental Engineering Research
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• 제11권5호
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• pp.266-276
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• 2006

Commonly, the flocculant is dissolved in process or recycle water in industrial plant which has many ionic materials. Therefore, the polymer degradation in aqueous solution by chemical, mechanical or bacteriological may occur, sometimes rapidly. Even if the same flocculant is dissolved, the flocculation characteristics and the properties of dissolving polymer varied with the kind of dissolving water. In this study, we try to estimate the interaction between flocculants and ionic materials in dissolving water using self inversing emulsion polymer; polyacrylamide-co-trimethyl ammonium ethyl acrylate chloride flocculants which have varying molecular weights and structures at a several conditions. The polymeric flocculant is dissolved in artificial dissolving water with Potassium Chloride (PC), Calcium Chloride anhydrous (CC), Potassium Hydroxide (PH), Sodium Chloride (SC), Sodium Bromate (SB) and Iron (II) Sulfate Heptahydrate (IS) as ionic sources. Experimental results indicate that the cationic and anionic ions in dissolving water induce the hydrolysis, degradation of cationic functional group and uncoiling of polymeric flocculants, therefore, the flocculation efficiency decreased by undesired polymer. According that result, it is important to estimate not only its structures and physical properties but also the qualities of dissolving water to optimize the efficiency.

• 환경위생공학
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• 제20권1호
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• pp.76-83
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• 2005

The process of reusing the treated water generated during this process and that of recovery of molybdenum from the excessive water were studied. The results were as follows. Molybdenum recollection 1. Reusing processing water generated after dissolving process on FL/20 type, the following were the remaining Mo.'s weights after the 1st, 2nd, 3rd, 4th, 5th, & 6th dissolutions respectively. 1) The result of measuring the quantity of Mo. in processing water(the 1st solving water) generated after the 1st dissolving Mo. process was $369g/\ell$ 2) The result of measuring the quantity of Mo. in processing water(the 2nd solving water) generated after the 1st dissolving Mo. process reusing the 1st solving water was $627.3g/\ell$ 3) The result of measuring the quantity of Mo. in processing water(the 3rd solving water) generated after the dissolving Mo. process reusing the 2nd solving water was $808.11g/\ell$ 4) The result of measuring the quantity of Mo. in processing water(the 4th solving water) generated after the dissolving Mo. process reusing the 3rd solving water was $934.68g/\ell$ 5) The result of measuring the quantity of Mo. in processing water(the 5th solving water) generated after the dissolving Mo. process reusing the 4th solving water was $1023.27g/\ell$ 6) The result of measuring the quantity of Mo. in processing water(the 6th solving water) generated after the dissolving Mo. process reusing the 5th solving water was $1085.29g/\ell$ 2. The followings were the results of recollectings Mo. in processing water respectively generated after dissolving Mo. to produce complete goods df FL/20 type filament. 1) the percentage of recollecting Mo. in the 1st solving water was $93.0\%$ 2) the percentage of recollecting Mo. in the 2nd solving water was $94.5\%$ 3) the percentage of recollecting Mo. in the 3rd solving water was $95.5\%$ 4) the percentage of recollecting Mo. in the 4th solving water was $96.0\%$ 5) the percentage of recollecting Mo. in the 5th solving water was $96.2\%$ 6) the percentage of recollecting Mo. in the 6th solving water was $96.4\%$ 3. The followings were the results of analyzing, with ICP, holding quantities of Mo. in the 6 processing waters to produce FL/20 type filament after passing a 3 staged solid-liquid separator through, dehydrating and drying for more than 3 hours in a dryer to recollect solving Mo. in them 1) the Mo. holding percentage in the 1st solving water was $76.6\%$ 2) the Mo. holding percentage in the 2nd solving water was $76.6\%$ 3) the Mo. holding percentage in the 3rd solving water was $76.6\%$ 4) the Mo. holding percentage in the 4th solving water was $76.6\%$ 5) the Mo. holding percentage in the 5th solving water was $76.6\%$ 6) the Mo. holding percentage in the 6th solving water was $76.6\%$ It was noted that with the number of times the recollecting Mo. percentage become higher, and in spite of much recollecting, without any large effect on the goods the solving water could be reused as the processing water. Because the collected Mo. holding percentages were more than $76\%$, it is considered they are very good one than Chinese Mo. ores with $50\%$ degrees of purity, worthy of recollecting Mo.

• 펄프종이기술
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• 제36권4호
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• pp.41-48
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• 2004

To make a basepaper for multipurposed seed paper, old news print (ONP) and mixed office waste paper (MOW), modified and unmodified with a commercial cellulase, were investigated. Each handsheet was applied with different chemicals such as insecticides, germicides and herbicides. The interactions behaviors of chemicals used with base papers were evaluated by means of the contents of chemicals impregnation and dissolving behaviors in water and soil. The ONP and MOW treated with the cellulase had higher impregnation and dissolving capacities in both water and soil than untreated ONP and MOW. However, the modified ONP showed lower impregnation and dissolving capacities compared to the modified MOW. The content of impregnation of chemicals would be affected with the degree of microfibrils produced by the modification treatment. Otherwise, dissolving capacities of chemicals depend on the affinity of the residual lignin in the paper.

• 폴리머
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• 제37권3호
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• pp.393-398
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• 2013

본 실험에선 미녹시딜을 함유한 수용성 고분자 젤로부터 solvent casting 방법으로 250과 $750{\mu}m$ 두 가지 길이의 미녹시딜이 함유된 용융형 고분자 마이크로 니들(micro-needle)을 제작하였다. 제작된 미녹시딜을 함유한 용융형 고분자 마이크로 니들은 기계적 강도가 입증된 고분자 니들과 동일한 형태 및 기계적 강도를 나타냈으며, 성공적으로 피부를 투과함을 확인하였다. 제조된 고분자 마이크로 니들의 경우 피부 적용 후 최소 30분 이상은 부착되어야 전체 니들의 50% (v/v) 이상이 피부 내로 용융되었으며, 니들 적용부위에서 서서히 약물의 방출 및 확산을 확인할 수 있었다. 또한 C57BL/6 동물 모델을 통해 미녹시딜이 함유된 250, $750{\mu}m$ 길이의 고분자 마이크로 니들이 무처리군 혹은 미녹시딜 처리군에 비해 발모에 긍정적인 영향을 나타냄을 확인할 수 있었다.

• 콘크리트학회논문집
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• 제11권3호
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• pp.153-160
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• 1999

Water soluble hydroxyalkyl methycellulose ethers are used in a variety of applications incluing building industry as a supplementary agent used for incresing adhesives, water retention capacity, workability and viscosity modify. Water retention capacity(WRC) is the capability to contain water in the ploymer chain under condition of being mixed with cement. In general, the WRC is affected by the viscosity, the adding amount, the particle size, the rate of dissolving and the amount of substituted chemical in cellulose ethers. In the other words, WRC is increased as higher the viscosity, more adding amount, finer the particle size and longer the dissolving time of cellulose ethers. This thesis investigated each factor that effect the WRC, particularly the relation between degree of substitution(DS), molar of substitution(MS) and WRC. It is observed that WRC is not nearly affected by DS of cellulose ethers, but is changes proportionally as MS increases in the narrow range(0.10~2.25)

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제3권1호
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• pp.23-31
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• 1999

An advanced mobile technology is described for saturating water with oxygen. The MTR(Mass Transfer Reactor) is 2~10 times more effective in dissolving oxygen in water compared to most other systems used in aquaculture, because it can generate extremely small(0.005~0.05mm) bubbles. New fish farming facilities could make use of this technology to build deeper ponds for raising multiple species with optimized conditions for DO(dissolved oxygen), food, light, etc. The proposed technology offers higher DO levels with minimal operating costs. It is easy to use and maintain, with a high reproducibility. Accordingly, the MTR can be industrially applied in the treatment of fish waste and reduction of water consumption during fish farming.

• 대한치과보철학회지
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• 제9권1호
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• pp.41-45
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• 1969

A major disadvantage of Dental cements is their solubility. So it is very important to measure the exact amount of solubility to select clinically suitable materials. The most common laboratory test for solubility is the measurement of disintegration in distilled water, as outlined in A.D.A. Specifications 8 and 9, In addition to the possible factors influencing the solubility, the experiments were all conducted in compliance with A.D.A. Specifications. The solubility of 2 Zinc Phosphate cements and 1 Silicate cement in time of dissolution, concentration of solute in dissolving medium, and type of dissolving medium were investigated. The following results were obtained. 1. Generally the materials were more soluble in organic acids than in distilled water. 2. The dissolution cements tends be minimized by tests utilizing prolonged storage in the same media. 3. In Acetic acid solution, Zinc Phosphate cements were more soluble than Silicate cement, and in Citric acid solution both were markedly more soluble. 4. Solubility was increased by continually presenting fresh liquid, unsaturated with solute, to the cement-water interface.

• 한국환경과학회지
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• 제24권7호
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• pp.947-954
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• 2015

Dielectric barrier discharge plasma is a new technique in water pollutant degradation, which that is characterized by the production of chemically active species such as hydroxyl radicals, ozone, hydrogen peroxide, etc. If dissolving of plasma gas generated in the plasma reaction has increased, it is possible to increase the contaminant removal capacity. In this study, the improvement on the dissolving performance of plasma gas was evaluated by the indirect method measuring the overall oxygen transfer coefficient. Experiments were conducted to examine the effects of nozzle type, distance from water surface, air supply rate and liquid circulation rate. The experimental results showed that the $K_{La}$ value of the 3-prong nozzle is 2.67 times higher than the diffuser. The order of $K_{La}$ value with nozzle type ranked in the following order: 3-prong nozzle (inner diameter, less 1 mm) > circular nozzle (inner diameter, 1.5 mm) > ellipse nozzle (short diameter 1 mm, long diameter 2.5 mm) > circular nozzle (inner diameter, 3 mm). Optimal liquid circulation rate was appeared to be 1.7 L/min, the value of $K_{La}$ was 0.510 1/min. The value of $K_{La}$ with increasing air supply rate was revealed in the form of an exponential such as $K_{La}=0.3581e^{0.2919^*air\;flow\;rate}$.

• 한국자기학회지
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• 제18권5호
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• pp.174-179
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• 2008

자장감응도가 약 0.8 %/Oe인 거대자기저항-스핀밸브(GMR-SV) 소자를 이용하여 두께 200 nm의 Mg-박막과 두께 $50\;{\mu}m$의 Mg- 포일이 물속에서 녹는 Mg 용해도 측정 센서 시스템을 제작하였다. Mg-박막과 Mg-포일이 각각 용해할 때, 증가하는 저항으로 인한 전류 감소가 솔레노이드 내부의 자기장의 변화를 일으켜 GMR-SV 센서로 감지되었다. Mg이 음용수와 반응하여 발생하는 방울수와 산화환원전위(ORP)의 시간 변화율을 측정하여 일반 수돗물과 증류수의 것과 비교하였다. 미네랄 Mg함량이 다른 3가지 물에서 Mg 용해속도가 큰 차이를 보였다. 또한 Mg-박막 일 경우, 출력신호의 자기저항 값이 최소 $43.6\;{\Omega}$로 떨어졌으며 자기저항의 급격한 변화가 5분 이내에 나타났고, 그 변화율은 ${\Delta}R/{\Delta}t=0.18\;{\Omega}/min$ 이었다. Mg-포일 일 경우, 20분 이내에 $0.3\;{\Omega}/min$이었다. 음용수에 담긴 Mg-박막이나 Mg-포일의 용해시간과 용해속도를 측정하여 알칼리 환원수로 변환을 감지하는 미네랄 Mg 용해센서 개발이 가능할 것으로 사료된다.

• 생물환경조절학회지
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• 제21권3호
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• pp.163-169
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• 2012

관비재배 및 수경재배시 비료를 녹일 때 소요되는 시간과 노동력을 절감하고, 작업의 안전성 확보와 자동화를 가능하게 할 수 있는 장치의 개발을 위해 본 실험을 실시하였다. 실험은 세 종류로 수행되었다. 먼저, 효과적인 비료용해 방법을 구명하기 위해 수중펌프를 양액 통 속에 두고 양액 통의 입구에 삼베포를 깐 거름망을 설치하여 물을 스프레이하여 비료를 녹이는 방법(Spray), 수중프로펠러를 이용하는 방법(Propeller), 수중펌프를 양액 통 속에 넣어 물의 흐름을 만들어 주는 방법(Submerged), 에어컴프레서를 이용하여 양액 통 속에 공기흐름을 만들어 비료를 용해하는 방법(Airflow) 등 4개의 처리를 두고 실험하였다. Spray 처리에서 가장 시간이 짧게 소요되는 것으로 조사되었으나 농가가 실제로 적용하는데 어려움이 있어서, Spray 처리 다음으로 비료를 녹이는 시간이 짧고, 노동력을 절감할 수 있으며 양액제조 과정을 자동화 하는 것이 용이할 것으로 사료되는 Airflow 처리를 선택하였다. 두 번째 실험에서는 Airflow 처리에서 사용한 재질과 분지관수를 개선한 6지관 및 8지관 장치를 제작하여 비교 실험했는데, 6지관 장치가 비료용해시간이 짧고, 양액탱크의 입구 크기에 관계없이 사용이 가능하며, 제작이 용이하여 가장 효과적인 장치로 판단되었다. 세 번째 실험에서는 개발된 6지관 장치를 이용하여 비료를 용해하는데 소요되는 시간을 조사하여 경제성을 분석하였는데, 농가에서 수중펌프를 이용하여 비료를 용해하는 방법보다 시간은 1/8배 절약할 수 있으며 경제성이 큰 것으로 나타났다. 아울러 $KNO_3$, $Ca(NO_3)_2{\cdot}4H_2O$, Fe-EDTA 등의 용해특성을 조사했다.