• Journal of Korean Society of Environmental Engineers
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• v.32 no.11
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• pp.1024-1029
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• 2010

Use of polymeric soil amendments is an emerging way to reduce soil erosion, and improve crop productivity and soil quality. Objective of this study was to evaluate the effects of anionic polyacrylamide (PAM) and synthetic biopolymer on soil erosion, crop growth and soil quality. The aqueous solutions of PAM and biopolymer at 40 kg/ha were applied to loamy soil plots (3 m width by 18 m long) having a 20% slope during radish (Raphanus sativus) cultivation. Results showed that PAM and biopolymer treatments increased aggregate stability up to 11% compared to the untreated control. Treatments of PAM and biopolymer also increased leaf length of radish but there was no significant difference in crop yield. Soil loss was decreased by up to 41% using the polymeric soil amendments; however, no difference in runoff was found, compared to the untreated control. Soil loss was logarithmically increased against an increase in rainfall intensity ($R^2=0.85$). Our findings suggest that proper use of polymeric soil amendments would be beneficial to maintain soil quality and reduce soil erosion in sloping uplands.

• Applied Chemistry for Engineering
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• v.21 no.1
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• pp.34-39
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• 2010

Methacryloxypropyltrimethoxysilane (MPTMS) was used for the surface modification of silica nanoparticles in the toluene dispersion system for 8 h (MPSN). Then, methacryloxypropyl-modified silica nanoparticles were successfully prepared by solutioun polymerization in the ethanol solution at $60^{\circ}C$ for 14 h with adding AIBN initiator. The modification of ultra-fine particles (SiOx-PAA nanospheres) was investigated via EA, XPS, FTIR, TGA, SEM and TEM. The mean diameter of the bare silica nanoparticles, MPSN and SiOx-PAA monodisperse nanoparticles was about 25, 30 and 35 nm, respectively.

• Polymer(Korea)
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• v.39 no.3
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• pp.403-411
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• 2015

A series of hydrophobically associating fluorinated amphiphilic polyacrylamide copolymers with remarkably high heat resistance and salt tolerance were synthesized by free radical micellar copolymerization, using acrylamide (AM) and sodium 2-acrylamido-tetradecane sulfonate ($AMC_{14}S$) as amphiphilic monomers, and 2-(perfluorooctyl) ethyl acrylate (PFHEA) as hydrophobic monomer. The structure of the terpolymer was characterized by FTIR, $^1H$ NMR and $^{19}F$ NMR. The solution properties of the terpolymers were investigated in details, and the results showed that the terpolymer solution had strong intermolecular hydrophobic association as the concentration exceeded the critical association concentration 1.5 g/L. The terpolymer solution possessed high surface activity, viscoelasticity, excellent heat resistance, salt tolerance and shearing resistance. The viscosity retention rate of copolymer solution was as high as 59.9% under the condition of fresh wastewater, $85^{\circ}C$ and a 60-days aging test.

• The Korean Journal of Mycology
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• v.8 no.3
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• pp.159-166
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• 1980

Aspergillus niger van Tieghem was cultured by the method of submerged and synchronized culture for the study of differentiation. Acid-phenol soluble cell proteins of the fungus were extracted from four stages during development. Those acid-phenol soluble proteins were separated by polyacrylamide gel electrophoresis to determine the protein patterns. A new protein band was observed from the pre-sporulation body, color density of the stained protein bands in four tubes differed according to the differentiation stages. The number of protein bands in 10% gels varied from 18 to 16, 17, and 19 according to the course of spore germination stage, conidiophore stage, phialide maturation stage and sporulation stage.

• Journal of Oral Medicine and Pain
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• v.22 no.2
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• pp.253-260
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• 1997

한국인 집단에서 개인식별의 기초자료로 활용하고자 한국인 201명을 대상으로 STR 유전좌위 중 하나인 LPL 유전좌위의 유전자 빈도 및 유전자형 분포를 구하였다. 혈액으로부터 추출한 핵 DNA를 중합효소연쇄반응으로 증폭시키고 폴리아크릴아마이드 겔 상에서 전기영동하여 은염색한 후 관찰하여 다음의 결과를 얻었다. 1. 한국인 집단 201명의 LPL 유전자에서 5개의 대립유전자, 7개의 유전자형을 검출하였으며, 이형접합도는 50.7%로 나타났고 대립 유전자다양성 (allelic diversity value)은 0.454, 개 인식 별력 (PD)은 0.674를 보였다. 2. 대립 유전자 및 유전자빈도는 9, 10, 11, 12, 13 대립 유전자에서 각각 0.020, 0.714, 0.100, 0.164, 0.002로 나타났으며, 대립유전자 7, 8, 14는 관찰되지 않았다. 이상의 결과를 볼 때 한국인 집단에서 STR LPL유전좌위의 유전자빈도는 친자감정 등 개인식별에 유용하게 사용할 수 있으나 감정실무에 응용시 다수의 STR유전좌위 및 VNTR유전좌위의 분석을 병행하여야 할 것으로 사료된다.

• Polymer(Korea)
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• v.38 no.6
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• pp.760-766
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• 2014

Bead type super-absorbent resins to be used for release-control were prepared by modification of the inverse suspension polymerization, and their physical properties were characterized. Acrylic acid and acrylamide were used as monomers, and N,N-methylenebisacrylamide was used as crosslinker, controlling the viscosity of monomer solution by adding hydroxyethylcellulose (HEC). SEM studies of the synthesized beads verified that the bead surfaces had many pores with their diameters of several tens nm. The bead sizes were in the range of $500{\sim}3000{\mu}m$, depending on the viscosity of the monomer solution. Both absorbent amount and absorbent rate of the beads were inversely proportional to the bead size, and the maximum water absorbent amount of 1 g beads was determined to be ca. 170~200 g for 5 hrs. The absorbent rate was also dependent on pH change of the aqueous solution, exhibiting the maximum rate in pH ranging from 5 to 11. The absorbent rate decreased as the concentration of salt (NaCl and $MgCl_2$) or ethanol and ethylene glycol increased. Release time of the water absorbed into the bead resins was 700 hrs, confirming the usefulness of the resin for the good release-control materials.

• Journal of Oral Medicine and Pain
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• v.25 no.1
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• pp.29-39
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• 2000

Lysyl Oxidase from fetal bovine aorta was purified to homogenity using extraction, Sephacryl S200HR chromatography, Hydropore AX ion-exchange high performance liquid column chromatography, Cibacron blue affinity chromatography, and Sephacryl S-300 HR chromatography in the presence of protease inhibitor. The purified enzyme was active toward lathyritic collagen as well as elastin and was sensitive to aminonitriles such as BAPN. Upon Sephacryl S-300 HR chromatography, the enzyme was eluted as a peak with a $K_{av}$ value of 0.45 (65% of $V_t$ ) and it eluted from high performance liquid ion-exchange column (Hydropore |AX) at single position (ionic strength, I = 0.1~0.15). Once purified, it showed one band upon SDS-PAGE. It migrated to a band the mobility of which corresponded to a Mr of 33,500 upon reduction while it migrated to a 24,500 Mr position under the non-reducing condition. In constrast to other reports, it is concluded that fetal bovine aorta contains only one type of lysy oxidase.

• Applied Chemistry for Engineering
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• v.29 no.2
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• pp.155-161
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• 2018

For the efficient recovering of collapsed sloped soil, using a soil binder that can support the soil strongly and help the growth of plants is very important. The soil binder should also have functions of recovering the soil ecologically as well as be environmental friendly materials. In this research, optimum values of the water content and permeability and direct shear strength were searched by adding the water absorbent and coagulant into the soil binder. The polyacrylamide (PAM) with various anionic strength, super absorbent polymer (SAP) and cellulose ether (CE) were used as a soil binder, water absorbent and coagulant, respectively. Effects of the soil binder on the characteristics of soil were observed by changing the mixing ratio of PAM, SAP and CE. Experimental results showed that the soil binder increased the direct shear strength tens of times and the water content around two times, whereas decreased the water permeability. Also, the addition of CE to increase the coagulation of SAP increased more of the direct shear strength and water content.

• Applied Biological Chemistry
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• v.41 no.7
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• pp.522-526
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• 1998

Ferritin from germinated soybean seeds was purified by ammonium sulfate precipitation (0.55 saturation), ion-exchange chromatography on DEAE-cellulose, gel filtration chromatography on Sephacryl S-300, and HPLC with Bio-Scale Q2 column. SDS-PAGE analysis showed that the purified ferritin is composed of subunit with an apparent M, 21,000. The molecular mass of the native soybean ferritin estimated by gel filtration on Sephacryl S-300 and non-denaturing polyacrylamide gel electrophoresis appeared to be $510{\sim}560\;kDa$. Soybean ferritin contained 833 mol Fe/mol protein, which is 31-fold more iron than pumpkin ferritin and stained positive for iron on non-denaturing gel. Soybean ferritin cross-reacted with anti-soybean rabbit ferritin antiserum.

• Korean Journal of Microbiology
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• v.33 no.4
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• pp.237-241
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• 1997

Lipase (EC 3.1.1.3) in the culture filtrate of Streptomyces coelicolor A3(2) was active on ${\alpha}$-naphthyl-butyrate as well as on various triacylglycerols with different lengths of acyl chains. The extracellular lipase was purified 15-fold by ammonium sulfate fractionation, Sephadex G-100, DEAE-Cellulose and Phenyl-Sepharose CL4B column chromatography with overall yield of 16%. It showed an molecular weight of 34.7 kDa by SDS-polyacrylamide gel electrophoresis. The enzyme activity with tributyrin as substrate was optimal at pH 8.0~9.0 and at $37^{\circ}C$. The enzyme activity decreased when the chain length of acyl group of triacyglycerol increased. A-factor, a hormone-like regulator of Streptomyces differentiation inhibited the lipase activity, which might corelate with the low enzyme activity in early exponential growth phase.