• Analytical Science and Technology
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• v.19 no.4
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• pp.290-300
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• 2006

Disinfection by-products(DBPs), such as volatile trihalomethanes and the nonvolatile organochlorine acids, created by chlorination have been extensively studied. However MX which contributes 20-50% of the mutagenic activity in drinking water began to people's attention since 1990. Its chemical name is 3-chloro-4-dichloromethyl-5-hydroxy-2(5H)-furanone. According to WHO guidelines its concentration should be controlled, but its value has not been set up. Due to analytical difficulties in measuring this compound at such a low concentrations and lack of information on toxicity to human. Because concentration (ng/L) of MX in drinking water is low traditional testing methods are ineffective. Therefore this study compared LLE and SPE and have chosen SPE to improve preconcentration. MX has been identified in chlorinated drinking water samples in several countries but not in korea Therefore this study analyzed concentration of MX in different water sources and in spring water. This study examined the causes of changing MX content. Chlorine dosage, seasons, water temperature and distance from the source was all discoverd to be relavant. MX was analyzed in various treatment to find optimum disinfection methods. The outcome was that the concentration of MX was minimized when using biological activated carbon-O3 and granular activated carbon.

• Analytical Science and Technology
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• v.29 no.1
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• pp.29-34
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• 2016

This study explores the means by which MX can be effectively extracted from chlorinated water 3-Chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), a potent mutagen commonly found in chlorinated drinking water at concentrations of up to a few hundred ng/L, was quantitatively determined using sample enrichment followed by liquid-liquid extraction (LLE), derivatization to methylated form, and analysis with GC-MS. A 4-L water sample was enriched to a concentration of 0.4 L using a vacuum rotary evaporator at 30 ℃. MX in the water was extracted using ethyl acetate (100 mL × 2) as a solvent and MX in the extract was methylated with 10 % H₂SO₄ in methanol. MX was recovered at a rate of 73.8 %, which was higher than that (38.1 %) for the resin adsorption method. The limit of quantification and repeatability (as relative standard deviation) were estimated to be 10 ng/L and 2.2 %, respectively. This result suggested that LLE can be used for the determination of MX in chlorinated water as an alternative to more time-consuming resin adsorption method.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.6
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• pp.707-716
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• 2020

Spectroradiometers have recently been drawing great attention in earth observing communities for its capability for obtaining target's quantitative properties. In particular, light-weighted multispectral cameras are gaining popularity in many field domains, as being utilized on UAV's. Despite the importance of the radiometric accuracy, studies are scarce on the performance of the inexpensive multispectral camera sensors that have various applications in agricultural, vegetation, and water quality analysis. This study conducted assessment of radiometric accuracy for MicaSense RedEdge-MX multispectral camera, by comparing the radiometric data with an independent hyperspectral sensor having NIST-traceable calibration quality. The comaprison showed that radiance from RedEdge-MX is lower than that of TriOS RAMSES by 5 to 16% depending on the bands, and the irradiance from RedEdge-MX is also lower than RAMSES by 1~20%. The correction coefficients for RedEdge-MX alculated through the 1-st and the 3-rd order regression analysis were presented as a result of the study.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.715-718
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• 2004

Substantially improved methods for the preparation of europium-doped yttrium oxide red phosphor with the inclusion of alkali metal halides having a general formula $(Y_{1-x}Eu_x)_2O_3$:MX where 0.025${\leq}$x${\leq}$0.2 and MX is alkali halide in the mole ratio 0.025 to 0.6, more preferably between 0.05 to 0.2 mole, are reported. Another series of the red phosphor materials with general formula $(Y_{1-x-y}Gd_xEu_y)_2O_3$:MX where 0.05${\leq}$x${\leq}$0.40 and 0.025${\leq}$y${\leq}$0.20 and MX is alkali halide in the mole ratio 0.025 to 0.5, more preferably between 0.1 to 0.2 mole, has also been presented. The inclusion of alkali halide greatly increase the luminance of the materials. The materials are very soft with fine particle size less than 100nm. The phosphorescent materials have good luminance in VUV region.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2023.11a
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• pp.149-151
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• 2023

MX-S2X(선박중심직접통신)은 선박을 중심으로 한 D2D 통신을 통해 육상·선박·시설의 유기적 연결을 제공함으로써, 해양 분야의 4차 산업혁명에서 해상 통신 기술 인프라로서의 핵심 역할이 가능할 것으로 기대 된다. '초고속해상무선통신망 무설설비 다각화 및 통신연계 기술개발 '의 1단계 3차년도에서는 2차년도에 제작한 MX-S2X 1차 시제품에 대한 기능을 보완하고 ISM 대역의 소출력 요구사항을 만족하기 위한 DSSS을 적용하여 2차 시제품을 구현/제작하고 실제 해상환경에서 성능을 검증한다. 본 논문에서는 MX-S2X 2차 시제품에 대한 1, 2차 실해역 시험결과 및 향후 계획에 대해 공유한다.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.5
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• pp.515-517
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• 1996

The relative efficiencies of deposition into egg yolk of apo-carotenoic acid ester(APO-E, CAROPHYLL Yellow) and saponified marigold xanthophylls (MX), in the presence of canthaxanthin (CN), were determined using a wheat-based diet. APO-E was deposited with an efficiency of 50 percent and MX with an efficiency between 13 and 20 percent. The dose response relationship for MX was curvilinear with a decreased efficiency at higher concentrations. Canthaxanthin was deposited with and efficiency of 38 percent, irrespective of the source of yellow xanthophylls, up to a dietary concentration of 5.5 mg/kg. At a dietary MX concentration of 8.3 mg/kg the efficiency of deposition of CN declined to 24 percent. The results confirm that the replacement ratio of MX : APO-E is between 3 : 1 and 4 : 1 depending on the dietary inclusion of marigold pigment.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2002.10a
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• pp.153-153
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• 2002

수돗물의 염소소독 과정에서 부식질의 초기 분해생성물인 MX(Mutagen X)는 수돗물의 전체 돌연변이유발성의 최고 60%까지 차지하는 것으로 알려져 있다. 그러나 존재하는 농도는 수 ng/L로 정량분석을 위해서는 resin을 사용하여 10 ~ 20L의 물을 농축하여야 한다. 이 연구에서 MX의 농축에 사용된 resin은 XAD-4와 XAD-7HP의 1:1 mixture이었으며, 사용 전에 Soxhlet extractor를 사용하여 ethyl acetate와 methanol로 각각 12시간씩 세척하였다. 15L의 물 시료는 37%의 염산으로 pH 2에 맞춘 후 직경 2cm의 유리관에 15cm의 높이로 채워진 resin을 40mL/min의 유속으로 통과시켰다. 유리관에 잔류하는 물은 질소가스로 대부분 불어 제거한 후 ethyl acetate 200mL를 가해 1mL/min의 유속으로 흘려주어 MX를 용출시킨 후 회전증발기로 5mL의 부피까지 농축시키고 10% H$_2$SO$_4$ in MeOH 0.1mL를 가하여 6$0^{\circ}C$에서 methyl ester화하였다. 과포화된 $Na_2$SO$_4$ 수용액 0.3ml를 가한 후 MTBE 0.3mL로 추출하고 GC/ECD로 분석하였다. MX의 회수율은 60% 이상이었으며 일부수돗물 시료에 대해 분석하였다.

• Analytical Science and Technology
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• v.15 no.3
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• pp.221-228
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• 2002

AMX is one of extremely high mutagenic compound produced from the reaction of the chlorine and the organic compound during the disinfection of tap water. In this paper, the chemical derivatization of MX with 2% sulfuric acid-methanol, iso-propanol, sec-butanol and n-butanol derivatives for the GC/MS analysis were tested or compared. Limit of detection for the EI and NCI mode were 25 pg and 1.25 pg, respectively. The good linear calibration curve was obtained the range of 25~2500 pg by EI and NCI

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.2
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• pp.35-48
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• 1991

Installation periods of implants in Mx. and Mn., is related to pattern of bone formation. The purpose of this study was to observe histologic response in osseointegration at root formed implant-tissue interface at Mx. and Mn., the other is comparison of osseointegration level between Mx. and Mn. at 8 weeks. In this study, unilateral upper & lower molars were extracted in dog. After allowing to heal for 4 months, two kinds of osseointegrated implants Swedevents, Corevents-were inserted in dog. The specimens were treated by conventional method. The interface zones between bone and implant were investiigated using X-rays, light microscope. The following results were obtained from this study. 1. Around titanium implants that were installed in Ma and Mn., Radio lucencies don't exist 2. There are not inflammation and mobility of titanium implants that were installed in Mx. and Mn. Most of implant surface are covered by bony tissued partly by bone-marrow tissues. 3. Titanium implants installed in Mx, in contrast to same implants in Mn., shows more coverage by bone marrow tissue and lack of apposition lamellar bone, which lead to the assumption that bone formation in Mn. is faster than in Mx.

• Nuclear Engineering and Technology
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• v.55 no.10
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• pp.3831-3843
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• 2023

The adsorption behaviour of Se(-II) onto granite and MX-80 bentonite in Ca-Na-Cl solutions has been studied utilizing adsorption experiments and surface complexation modelling. Adsorption kinetic experiments allude to steady-state adsorption periods after 7 days for granite and 14 days for MX-80 bentonite. Batch adsorption experiments were carried out to determine the influence that the physicochemical solution properties would have on Se(-II) adsorption behaviour. Adsorption of Se(-II) onto granite and MX-80 bentonite follows the trend of anionic adsorption, with a decrease in R_d values as the solution pH increased. There is also an ionic strength influence on the adsorption of Se(-II) onto granite with a decrease in the R_d value as the ionic strength increased. This effect is not found when observing Se(-II) adsorption onto MX-80 bentonite. Final experiments with a representative groundwater, determined that the adsorption of Se(-II) onto granite and MX-80 bentonite returned R_d values of (1.80 ± 0.10) m³·kg^-1 and (0.47 ± 0.38) m³·kg^-1, respectively. In support of the experiments, a surface complexation modelling approach has been employed to simulate the adsorption of Se(-II) onto granite and MX-80 bentonite, where it was determined that two different surface complexes, ≡S_Se^- and ≡SOH₂⁺_H₂ were capable of simulating Se(-II) adsorption behaviour.