• 한국세라믹학회지
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• 제35권11호
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• pp.1227-1232
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• 1998

In order to prohibit the delay of early stage hydration activator Na2SO4 was added to Fly Ash blended ce-ment and its effects were investigated. Various measurements such as Compressive strength Heat of hy-dration Pore size distribution Hydration products Microstructure were evaluated and the results show that specimens of Fly Ash(50wt%) with 5% Na2SO4 dramatically improved the compressive strength because pozzolanic reaction of Fly Ash and the formation of ettringite make th microstructure denser than OPC and flyash cement paste.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2002년도 봄 학술발표대회 발표논문집
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• pp.70-74
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• 2002

해염농축계수는 해양기원인 $Cl^{-}$, $K^{+}$ 그리고 $Mg^{2+}$ 는 1.0 이상이고 10이하의 분포를 보였으나, $Ca^{2+}$ 와 ${SO_4}^{2-}$는 10 이상의 높은 값을 나타냈으며, ${So_4}^{2-}$는 상업지역, 공단지역, 주거지역 그리고 농업지역 순으로 조사되었다. 지역별 비해염 성분의 기여율은 $F^{-}$, $Ca^{2+}$ , ${So_4}^{2-}$, $K^{+}$, $Cl^{-}$ 그리고 $Mg^{2+}$ 의 순으로 나타났으며, 인위적 기원인 ${SO_4}^{2-}$은 상업지역(97.5%)이 가장 높은 해안지역 (71.5%)이 가장 낮게 나타났다. 해염입자의 기여율은 겨율 > 여름 > 가을 > 봄의 순으로서 겨울철 (47.4%)이 가장 높고, 봄철 (22.4%)이 가장 낮게 나타났다.

• 한국대기환경학회지
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• 제27권3호
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• pp.291-302
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• 2011

[ $PM_{10}$ ]measurements were made at two coastal sites, i.e., Taean and Gangneung, for summer to examine the characterization of water-soluble organic carbon (WSOC) and inorganic ionic species, and to investigate their difference between the sites. The fractions of three major inorganic water-soluble components ($NO_3^-$, $SO_4^{2-}$, and $NH_4^+$) at Taean and Gangneung sites were 30.6% (16.2~62.0%) and 25.6% (13.0~52.5%) of the $PM_{10}$, respectively. $SO_4^{2-}$ is the most dominant species of water-soluble ions at both sites, accounting for up to 20.5% (9.1~44.9%) and 16.3% (5.5~34.2%) of their respective PM10 mass concentrations. Using the paired T-test, $PM_{10}$ (p<0.01), $NO_3^-$ (p<0.05), $SO_4^{2-}$ (p<0.01), $NH_4^+$ (p<0.001), and WSOC (p<0.05) concentrations exhibited strong fluctuations on a daily basis between Taean and Gangneung sites. Relationship between the concentrations of $SO_x$ ($SO_4^{2-}+SO_2$) and CO indicates that the slopes of $SO_x$ /CO were 0.007 and 0.019 in the Taean and Gangneung sites, respectively. The smaller $SO_x$/CO slope in the Taean site could be related to the aged air with wet scavenging of $SO_x$ during transport. The correlation between the concentrations of CO and WSOC suggests that WSOC observed in the Gangneung ($R^2$=0.82) be transported from combustion-related sources, while the WSOC at the Taean site could be formed through atmospheric processing of primary volatile organic species during transport.

• 산업기술연구
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• 제39권1호
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• pp.15-19
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• 2019

This work focused on characterization of the starch degradation activity from extremophile strain Deinococcus geothermalis. Glucoamylase gene from D. geothermalis was cloned and overexpressed by pET-21a vector using E. coli BL21 (DE3). In order to characterize starch degrading activity of recombinant glucoamylase, enzyme was purified using HisPur Ni-NTA column. The recombinant glucoamylase from D. geothermalis exhibited the optimum temperature as $45^{\circ}C$ for starch degradation activity. And highly acido-stable starch degrading activity was shown at pH 2. For further optimization of starch degrading activity with metal ion, various metal ions ($AgCl_2$, $HgCl_2$, $MnSO_4{\cdot}4H_2O$, $CoCl_2{\cdot}6H_2O$, $MgSO_4$, $ZnSO_4{\cdot}7H_2O$, $K_2SO_4$, $FeCl_2{\cdot}4H_2O$, NaCl, or $CuSO_4$) were added for enzyme reaction. As results, it was found that $FeCl_2{\cdot}4H_2O$ or $MnSO_4{\cdot}4H_2O$ addition resulted in 17% and 9% improved starch degrading activity, respectively. The recombinant glucoamylase from D. geothermalis might be used for simultaneous saccharification and fermentation (SSF) process at high acidic conditions.

• 한국의류학회지
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• 제39권2호
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• pp.287-293
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• 2015

This research verifies stainability, super bacteria antibacterial features and antibiotic resistance of Ulmus davidiana var. japonica Nakai (UD) extract in dye cotton cloth. UD was extracted with hot water, the test cloth dyed, and then processed by mordanting treatment using $FeSO_4$ $7H_2O$, $CuSO_4$ $5H_2O$ and $Al_2(SO_4)_3$. The surface color and color fastness of the three kinds (original cloth, the cloth without mordancy and mordant cloth) were measured and the influence of dying of cotton cloth and the mordant method on the genesistasis of Methicillin-resistant Staphylococcus aureus (MRSA), antibiotic resistant bacteria. 1. The surface color of the cotton cloth for dyeing (without and with mordancy) displayed a reddish and yellowish color. Stainability was greatest when the mordant of $FeSO_4$ $7H_2O$ was used. 2. When a mordant was not used for dyeing, the color fastness to washing, perspiration and friction of the contaminated cloth was satisfactory at 4 to 5 grade in general. 3. As for the antibiotic effect to super bacteria, the growth of germ was meaningfully suppressed both on the cloth without and with mordancy compared to the comparison cloth; in addition, the dyeing method with the biggest antibacterial impact was found to be the mordancy with the mordant of $CuSO_4$ $5H_2O$ after dyeing. The results of the experiments that involved dyeing with UD extract showed that cotton cloth processed through mordancy with the mordant of $CuSO_4$ $5H_2O$ had the biggest antibiosis to super bacteria and that processed with the mordant of $FeSO_4$ $7H_2O$ had the greatest stainability.

• 한국환경보건학회지
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• 제24권3호
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• pp.114-123
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• 1998

Particulate matters(less than 10 $\mu$m, PM10) at Kanghwa and Yangyang, which are located in the western and the eastern coastal regions in Korea, were measured in using low volume air sampler from December 1995 to November 1996, and their characteristics were investigated from the view point of background level.(and in order to characterize the particulate matters.) The particulate matters were analyzed for major water soluble ionic components(SO$_{4}^{2-}$, NO$_{3}^{-}$, Cl$^{-}$, Na$^{+}$, NH$_{4}^{+}$, K$^{+}$, Mg$^{2+}$ and Ca$^{2+}$) by ion chromatography. Mass concentrations of particulate matters were $48.77 \pm 22.45 \mug/m^{3}$ at Kanghwa and $54.04 \pm 32.98 \mug/m^{3}$ at Yangyang and SO$_{4}^{2-}$, NO$_{3}^{-}$ and NH$_{4}^{+}$ contributed largely to water soluble ionic components. nss(non sea salt)-SO$_{4}^{2-}$, contributed more than 95 percentage to SO$_{4}^{2-}$ and nss-K$^{+}$ and nss-Ca$^{2+}$ also contributed high percentages to K$^{+}$ and Ca$^{2+}$. It was supposed that most SO$_{4}^{2-}$, was originated from anthropogenic sources, and K$^{+}$ and Ca$^{+}$ were mainty originated from soil. The results of factor analysis suggested possibility of interpreting the correlation between air pollutants and regional characteristics.

• 한국대기환경학회지
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• 제15권2호
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• pp.113-120
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• 1999

Winter and summer samples were collected from January 3 to February 7, 1997 and July 26 to September 11, 1997, respectively, in Seoul. This study was to characterize the concentrations of the annular denuder system (ADS) were $HNO_3$, $HNO_2$, $SO_2$ and $NH_3$ in the gas phase, and $PM_{2.5}$ ($d_p$〈2.5$mu extrm{m}$), $SO_4^{2-}$, NO3-, and $NH_4^+$ in the particulate phase. All chemical species monitored from this study showed statistical seasonal variations except for $SO_4^{2-}$ . Nitric acid (HNO3) and ammonia ($NH_3$) exhibited substantially higher concentrations during the summer, while nitrous acid ($HNO_2$) and sulfur dioxide ($SO_2$) concentrations were higher during the winter. $PM_{2.5}$, $NO_3^-$, and $NH_4^+$ were higher leves in the winter. High correlations were found among $PM_{2.5}$, $NO_3^-$ $SO_4^{2-}$ and $NH_4^+$ during two seasons.

• 자원리싸이클링
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• 제10권1호
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• pp.25-31
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• 2001

폴리염화비닐(PVC) 64.5%, 프탈산디옥틸(DOP) 32.2%, 칼슘-아연 스테아린산 안정제 및 계면활성제 등으로 되어진 PVC 필름을 $H_2O$, $Ca(OH)_2$ 그리고 $H_2$$SO_4$용액중에서 반응온도 $200-250 ^{\circ}C$, 반응시간 0-12시간으로 수열처리하였을 경우 PVC의 탈염화수소 및 생성되는 탄소질에 관해서 조사했다. $ H_2$ $SO_4$의 경우에는 탈염화수소가 빨라 25$0^{\circ}C$, 3시간 이상에서는 탈염화수소율이 거의 100%에 도달했다. 또한 이들의 수열처리에서는 다공질의 탄소질이 생성되었고 온도가 높을수록, 그리고 반응시간이 길수록 이들의 세공경은 작아졌다. $Ca(OH)_2$의 경우에는 $225^{\circ}C$, 12시간에서는 약 5-10 $mu extrm{m}$정도의 세공이 생성되었다. 그리고 $H_2$$_SO4$의 경우에는 5M의 $_H2$$SO _4$로 12시간 처리하였을 경우 약1 $\mu\textrm{m}$정도가 되었다

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.109-116
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• 2018

$Eu_2(SO_4)_3$ was synthesized by chemical precipitation method and the crystal structure was determined by Rietveld analysis. The compound crystallizes in monoclinic space group C2/c. In the air environment, $Eu_2(SO_4)_3$ is stable up to $670^{\circ}C$. The sample of $Eu_2(SO_4)_3$ was examined by Raman, Fourier-transform infrared absorption and luminescence spectroscopy methods. The low site symmetry of $SO_4$ tetrahedra results in the appearance of the IR inactive ${\nu}_1$ mode around $1000cm^{-1}$ and ${\nu}_2$ modes below $500cm^{-1}$. The band intensities redistribution in the luminescent spectra of $Eu^{3+}$ ions is analyzed in terms of the peculiarities of its local environment.

• Journal of Animal Science and Technology
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• 제51권2호
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• pp.171-176
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• 2009

우사주변 경작지 토양으로부터 세포내 파이테이즈 (phytase) 생산능력이 우수한 Fluorescent Pseudomonas sp. BUN1 세균성 균주를 분리, 동정하였다. 그 균주로부터 유래한 BUN1 파이테이즈 (phytase) 효소를 각각 양이온, 음이온 크로마토그래피 기법을 이용하여 부분정제하여 효소적 특성을 규명한 결과, 각각 $40^{\circ}C$와 pH 5.5에서 최적의 효소활성을 나타내었다. BUN1 파이테이즈 (phytase)는 효소의 기질특이성 측면에서 다른 유기인산화합물에 비해 특히 피틴태인 (phytate)의 분해이용성이 매우 우수한 반면, 구리 ($Cu^{2+}$), 카드뮴 ($Cd^{2+}$), 아연 ($Zn^{2+}$)과 같은 금속 2 가이온에 대하여 그 효소활성이 강하게 억제되었다. 또한 BUN1 균주의 효소생산 배지 (PSM) [0.5% sodium phytate, 0.5% $(NH_4)_2SO_4$, 0.5% KCl, 0.01% $MgSO_4{\cdot}7H_2O$, 0.01% $CaCl_2{\cdot}2H_2O$, 0.01% NaCl, 0.001% $FeSO_4{\cdot}7H_2O$, 0.001% $MnSO_4{\cdot}4H_2O$; pH 6.5]에 탄소원으로서 옥수수전분 (corn starch)의 첨가는 조사된 다른 탄소 배지원에 비하여 현저하게 파이테이즈 (phytase) 생산을 촉진시켰다.