• 한국화재소방학회논문지
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• 제28권6호
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• pp.108-113
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• 2014

유해물질처리를 효율적으로 개선하기 위해 슬라이딩아크방전(sliding arc plasma)과 corona dielectric barrier discharge(CDBD공정)의 복합공정을 이용하였다. 이장치는 OH 라디칼과 음이온을 생성하여 강력한 산화력으로 탈취 및 살균 효과를 가진다. 실험결과 SAP 반응기의 크기를 80 A를 50 A로 축소하여도 유해물질의 농도는 큰 변화가 없는 것으로 나타나 반응기의 규모를 최소화할 수 있을 것으로 판단된다. 그리고 CDBD 반응기에서 생성된 음이온과 오존은 유해물질과 반응한 후 음이온은 510,000 ppb에서 470 ppb, 오존은 98 ppb에서 22 ppb로 낮아짐을 확인하였다. 또한 플라즈마 발생장치의 안정성 및 내구성이 우수한 것으로 판단되었다. 따라서 본 연구를 통하여 향후 플라즈마복합공정을 이용하여 실내공기중에 존재하는 유해물질 제거를 효율적으로 할 수 있을 것으로 생각된다.

• 한국대기환경학회지
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• 제10권2호
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• pp.124-129
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• 1994

Aerosol size distribution was determined using Anderson sampler for the anions( sulfate nitrate and chloride ) and TSP. Ionic species concentration and size distribution have been investigated in the daytime and nightime individually. Size classified samples were extracted with distilled water and analyzed for C $l^{[-10]}$ , N $O_3$$^{[-10]}$ and S $O_4$$^{2-}$, by ion chromatography. The size distribution of these ions and TSP was analyzed to investigate the seasonal and diurnal variation of concentrations as follows: (1)Size distribution of TSP showed bi- modal type in the daytime, but indicated tri-mode distribution in the nightime without any seasonal variation. (2)Sulfate concentrations were higher in fine- mode both in the daytime and nightime but fraction of sulfate was higher in coarse-mode during the Yellow Sand Period. (3)Nitrate and Chloride ions are dominant in fine-mode in winter while dominant in coarse-mode in the summer.

• Journal of Forest and Environmental Science
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• 제15권1호
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• pp.89-97
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• 1999

산지계류에 서식하는 수서곤충의 종류와 서식조건에 대한 기초자료를 얻기 위해 강원대학교 산림과학대학 부속연습림내의 봉명천을 대상으로 수서곤충, 음이온 및 하상재료를 파악한 결과는 다음과 같다. 1. 각 지점별 수서곤충의 종다양도, 종풍부도 및 균등도는 사방댐의 상류역이 하류역보다 높게 나타났다. 2. 음이온은 A, B, C, D 및 E 지점 모두 유사하였지만 하류역인 F지점에서는 상류역에 비해 최소 1.5배에서 최대 89배 이상의 이온이 검출되었다. 3. 하상재료는 상류역이 하류역보다 입경이 크게 나타났으나, 사방댐 직하부는 사방댐에 의해 하류역보다 자갈의 구성도가 높게 나타났다. 4. 수서곤충의 수는 음이온 농도에 반비례하였고, 하상재료의 크기와는 정비례하였으며, 특히 호박돌의 분포도에 크게 영향을 받은 것으로 나타났다.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 추계 총회 및 학술발표회
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• pp.142-145
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• 2004

Anion-exchange porous hollow-fiber membranes with a thickness of about 1.2 mm and a pore size of about $0.30{\mu}m$ were used as a supporting matrix to immobilize cycloisomaltooligosaccharide glucanotransferase (CITase). CITase was immobilized to the membrane via anion-exchange adsorption and by subsequent enzymatic cross-linking with transglutaminase, the amount of which ranged from 3 to 110 mg per g of the membrane. The degree of enzyme multilayer binding was equivalent to 0.3 to 9.8. Dextran, as the substrate, was converted into seven- to nine-glucose-membered cycloisomaltooligosaccharides (CI-7, -8, and -9) at a maxi mum yield of $28\%$ in weight at a space velocity of 10 per hour during the permeation of $2.0(w/w)\%$ dextran solution across the CITase-immobilized porous hollow-fiber membrane.

• KSBB Journal
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• 제28권2호
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• pp.131-136
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• 2013

The hydrolysates prepared with various enzyme digestion of Capsosiphon fulvescens were used to measure the inhibitory effects against angiotensin I converting enzyme (ACE). The commercially available enzymes such as Celluclast, Viscozyme, Lysing enzyme, Flavourzyme, Alcalase and Pectinex were used to digest C. fulvescens and produce hydrolysates. The maximum ACE inhibitory activity was observed using Alcalase hydrolysis (72.9%). The optimal conditions of Alcalase extraction were pH 8.0 and extraction time for 12 hr. The hydrolysates were fractionated using preparative-LC and anion-exchange chromatography on DEAE-cellulose and the fraction B and B-2 were isolated. The ACE inhibitory activity of fraction B-2 by anion-exchange chromatography was 82.6%. The molecular weight of fraction B-2 estimated using size exclusion chromatography was about 1 kDa. The monosaccharide composition of the fraction B-2 was determined to be mannose (1.1%), glucuronic acid (1.3%), galactose (1.3%) and glucose (96.3%).

• Membrane and Water Treatment
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• 제8권4호
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• pp.369-380
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• 2017

Performance evaluation of four commercially available tubular membranes (AFC 80, AFC 30, PU 608, ES 404) was accomplished in self-assembled membrane testing unit. Effects of varying transmembrane pressure, feed concentration and anion type were investigated. Aqueous solutions of salts such as calcium chloride, calcium sulfate, tin chloride and tin sulfate were prepared for this study. It was noted that the investigated parameters e.g., pressure and concentration had significant effects on membrane's performance. Nevertheless, anion type effectively played its role in the rejection of salts since salt having SO4-2 anions had a better rejection than the salts containing Cl-1. It is observed that rejection was dominated by Donnon exclusion for strongly charged nanofiltration membranes whereas for weakly charged ultrafiltration membranes, size exclusion was the key mechanism to reject the ions.

• 한국대기환경학회지
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• 제2권3호
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• pp.27-33
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• 1986

Atmospheric particulate matter (A. P. M.) was collected and size-fractionated by an Andersen high-volume air sampler over 15 month period from Jan. 1985 to Feb. 1986 in Seoul. The concentration of chloride, nitrate and sulfate were extracted in an ultrasonic bath and were analyzed by ion chromatography. The annual arithmetical mean of A. P. M. was 128.54 $\mug/m^3$. The concentration of anions were 2.88 $\mug/m^3$ for chloride, 3.86$\mug/m^3$ for nitrate, and 25.44$\mug/m^3$ for sulfate. The content of A. P. M. was lowest in the particle size range 1.1 $\sim 3.3\mum$ and increased as the particle size increased or decreased. And the anions exhibited a seasonal variation in the isize distribution. The contents of anions were higher in winter than summer. Ther ratio of fine particles to the total particles defined by F/T for chloride, nitrate and sulfate. The F\ulcornerT of these anion generally decrease with increasing air temperature. This tendency was prevalent in the chloride and nitrate.

• Journal of Korean Society for Atmospheric Environment
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• 제22권E1호
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• pp.27-34
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• 2006

Although the importance of size-resolved raindrops study has been known, it has not been popularized up to the present. In the present study, an attempt was made to generalize the size-resolved raindrops study by a combination of the frozen raindrop collection method and a commercially available high-performance capillary electrophoresis (HPCE). Samplings were carried out at Kyoto, Japan in October 2002. The inorganic ions (chloride, nitrate, sulphate, calcium, ammonium, sodium, magnesium, potassium) in size classified raindrop samples were successfully analyzed by HPCE with good repeatability. To assure the accuracy and precision of HPCE data, t-test was conducted with paired analytical data, which were experimentally constructed by analyzing standard solutions with HPCE and IC, respectively. T-test showed that there is no notable difference between the concentrations determined by the two analytical methods. Every ionic concentration in both cation and anion was found to be strong raindrop size dependence. Though there was slight increase of sodium and sulphate concentrations between 0.85 mm and 1.15 mm raindrop radius, it showed a strong decrease for every ionic component with increasing droplet radius. The combination of the frozen raindrop collection method and a commercially available HPCE can meet the need of size-resolved raindrops study.

• 대한화학회지
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• 제29권3호
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• pp.233-238
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• 1985

비다공성 및 다공성 폴리스티렌 디비닐벤젠 공중합체를 합성하고, 이것을 클로로메틸화 한후, 메틸아민으로 아미노화하여 약염기성 음이온교환수지인, 50∼100mesh의 비다공성, N-APSTDVB와 다공성, P-APSTDVB를 만들었다. 합성한 이들 음이온교환수지를 적외선 흡수스펙트럼으로 확인하였다. 이들 음이온교환수지의 최대 이온교환용량은 4.86meq/g이었다. 다공성 폴리스티렌 디비닐벤젠 공중합체, P-APSTDVB의 세공용적은, 디비닐벤젠의 볼륨퍼센트를 30%로 하였을 때, X$_{diluent}$의 증가에 따라서 증가하였다. 또한 X$_{diluent}$의 양을 0.5로 일정하게 하였을때, P-APSTDVB공중합체의 세공용적은, 디비닐벤젠의 볼륨퍼센트가 증가함에 따라 증가하였다. 디비닐벤젠의 퍼센트를 8%로 일정하게 하고, X$_{heptane}$을 0.5로 하였을 때, 합성한 공중합체와 음이온교환수지의 세공용적은, P-PSTDVB >P-APSTDVB >N-PSTDVB순으로 감소하였다. 여러 농도하에서의, 여러종류의 알코올 수용액중에서의 N-APSTDVB음이온교환수지에 대한 붕산의 분포계수가, 또한 논의되었다.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1517-1522
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• 2012

Anion effects on structures of $Cd^{II}$ complexes containing 2,2'-bipyridine (2,2'-bpy) ligands have been studied, and compared with $Zn^{II}$-(2,2'-bpy) complexes. For each anion, different structures have been obtained in both $Zn^{II}$-(2,2'-bpy) and $Cd^{II}$-(2,2'-bpy). Polymeric structures of $Cd^{II}$-2,2'-bpy complexes can be produced by hydrogen bonding interactions as shown in $Zn^{II}$-2,2'-bpy complexes. In addition, the bigger size of a $Cd^{II}$ ion gives higher coordination numbers forming variety of structures, and it makes that chlorides can act as bridging ligands to form a one-dimensional structure. The compound $\mathbf{5}$ catalyzed efficiently the transesterification of a variety of esters with methanol, while the rest of the compounds have displayed very slow conversions. In addition, the emission bands of complexes $\mathbf{1}$, $\mathbf{2}$, $\mathbf{4}$, and $\mathbf{6}$ are blue-shifted compared to the corresponding ligand 2,2'-bpy, whereas $\mathbf{3}$ and $\mathbf{5}$ showed the similar emission observed for the ligand.