• Journal of Korean Society for Atmospheric Environment
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• v.10 no.1
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• pp.64-72
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• 1994

Recently, the acid precipitation, composed primarily of dilute $H_2$S $O_4$, HN $O_3$and originating from the burning of fossil fules, has become one of the major environmental problems. This study was carried out to investigate the chemical features of precipitation at Sobaek-san Meteorological Observation Station(mean sea level; 1,340m, 36$^{\circ}$56’N, 128$^{\circ}$27' E)from May 1991 to December 1993. The major Point in this study divided the whole wind directions into two parts. And, the two parts are the north- westerly wind case and south-easterly wind case. The concentration of anions and cations in precipitation were measured by ion chromatography(Dionex 4000i). The volumn weighted mean pH and conductivity values of the whole precipitation period were 5.26, 14.3$mutextrm{s}$/cm, respectively. The order and frequency rate of the major anions concentration in the north- westerly and south easterly wind case were S $O_4$$^{2-}$(49.3%) ＞ N $O_3$$^{[-10]}$ (23.9%) ＞ C $l^{[-10]}$ (14.8%) ＞ $F^{[-10]}$ (12.0%) and S $O_4$$^{2-}$(61.1% ) ＞ N $O_3$$^{[-10]}$ (21.5%) ＞ C $l^{[-10]}$ (13.5%) ＞ F/sip -/(4.0%), respectively. The order and frequency rate of the major cations concentration in the north-westerly and south- easterly wind case were $Ca^{2+}$(49.3%) > N $H_4$$^{+}$(24.2%) >N $a^{+}$(22.4%) ＞M $g^{2+}$(14.9%) > $K^{+}$(3.8%) and N $H_4$$^{+}$(4:3.8%) $Ca^{2+}$(28.6%) ＞ N $a^{+}$(16.8%) > $K^{+}$(6.3%) > $Mg^{2+}$(4.5%), respectively. The larger anions and cations concentration values than others were S $O_4$$^{2-}$, N $O_3$$^{[-10]}$ and $Ca^{2+}$, N $H_4$$^{+}$, respectively. The correlation coefficient between pH value and ion concentrations for the north-westerly and south-easterly wind case was shown less than 0.5 except for Ca/.sup 2+/ in the statistical analysis SPSS. But the correlation coefficient for the all wind case between sulfate and cations was shown high correlation above 0.6.correlation above 0.6.

• Microbiology and Biotechnology Letters
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• v.44 no.2
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• pp.171-179
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• 2016

Recent succession of soil microorganisms and vegetation has occurred in the glacier foreland, because of glacier thawing. In this study, whole microbial communities, including bacteria, archaea, and eukaryotes, from the glacier foreland of Midtre Lovénbreen in Svalbard were analyzed by metagenome sequencing, using the Ion Torrent Personal Genome Machine (PGM) platform. Soil samples were collected from two research sites (ML4 and ML7), with different exposure times, from the ice. A total of 2,798,108 and 1,691,859 reads were utilized for microbial community analysis based on the metagenomic sequences of ML4 and ML7, respectively. The relative abundance of microbial communities at the domain level showed a high proportion of bacteria (about 86−87%), whereas archaeal and eukaryotic communities were poorly represented by less than 1%. The remaining 12% of the sequences were found to be unclassified. Predominant bacterial groups included Proteobacteria (40.3% from ML4 and 43.3% from ML7) and Actinobacteria (22.9% and 24.9%). Major groups of Archaea included Euryarchaeota (84.4% and 81.1%), followed by Crenarchaeota (10.6% and 13.1%). In the case of eukaryotes, both ML4 and ML7 samples showed Ascomycota (33.8% and 45.0%) as the major group. These findings suggest that metagenome analysis using the Ion Torrent PGM platform could be suitably applied to analyze whole microbial community structures, providing a basis for assessing the relative importance of predominant groups of bacterial, archaeal, and eukaryotic microbial communities in the Arctic glacier foreland of Midtre Lovénbreen, with high resolution.

• Journal of Applied Biological Chemistry
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• v.56 no.3
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• pp.141-146
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• 2013

Constituents of the essential oil (EO)s and hydrosol of rosemary (Rosmarinus officinalis L.) and lavender (Lavandula angustifolia Mill.) were analyzed by gas chromatography-mass spectrometry (GC-MS). The identified major constituents were ${\alpha}$-pinene (40.96%), camphor (34.44%), verbenone (45.31%), and camphor (67.04%) in rosemary EO, lavender EO, rosemary hydrosol, and lavender hydrosol, respectively. The antioxidant activity of EO and hydrosol extracted from rosemary and lavender were evaluated. Both EO showed di(phenyl)-(2,4,6-trinitrophenyl) iminoazanium (DPPH) and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) free radical scavenging activities as well as $Fe^{2+}$ ion chelating activity but no alkyl radical scavenging activity. Rosemary EO showed higher DPPH radical scavenging activity than lavender, whereas lavender EO showed higher $Fe^{2+}$ ion chelating activity. Both rosemary and lavender hydrosols showed alkyl radical scavenging activity, but only lavender hydrosol showed an activity on $Fe^{2+}$ chelating assay. Both rosemary and lavender hydrosols also protected the dermal fibroblast and the HaCaT keratinocytes against $H_2O_2$-induced cytotoxicity.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.4
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• pp.267-273
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• 2008

The purpose of this study is to investigate the distributive property of organic pollutants in effluents of argo/industrial wastewater treatment plants in Jeonnam using simultaneous analysis method of 310 chemicals. The numerous organic pollutants were detected in four sampling sites and the major chemicals were pesticides, CH type chemicals such as polycyclic compounds, CHO type chemicals such as phthalates, and CHO(N) type chemical such as aromatic amines. Moreover, 17 kinds of endocrine disrupters which include diethylptbalate were detected in each sampling sites. TU (Toxic unit) indicated cytotoxicity of samples using XTT assay, it appeared highly at A point(27.2) and D point(24.4). Also, the results from the correlation between total concentration of pollutants and TU did not correspond to the results of chemical and biological analysis.

• Journal of the Korean Chemical Society
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• v.26 no.4
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• pp.229-234
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• 1982

Using solution technique, sulfur in the sulfide ore was indirectly determined by X-ray fluorescence spectrometry. The sample was dissolved with the mixed solution of B$r_2$ and HN$O_3$, and Si$O_2$, a major constituent, was repelled from the solution by HF treatment several times, B$a^{2+}$ solution was added to the solution to precipitate the S$O^4_{2-}$ ion as BaS$O_4$. Measuring the fluorescent X-ray intensity of excess Ba2+ ion in the filtrate, the content of sulfur in the original ore was back-calculated. Comparing the results by this method with the gravimetric method, the mean difference was ${\pm}1.7%$ in the range of 20 to 40% of sulfur content and the method was tolerably reproducible.

• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.334-338
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• 1998

Kale(Brassica oleracea var. acephala) is one of Cruciferous vegetables that is closely related to the wild ancestral form of cabbabe. The ethanol extract of kale which contains the active compoundsss under Salmonella assay system was fractionated with chloroform to collect the nonpolar solvent soluble compounds, and then further fractionation was carried out by silica gel column chromatography. Among kale extracts separated by silical gel column chromatography, the fractions of 4, 5 and 6 exhibited strong antimutagenic activities. The major active compounds from the fraction were identified as chlorophyll derivatives by the analysis with HPLC-fritp-MS. The molecular weights of each chlorophyll derivatives in the sample were acquired from the peaks of positive ion atomosphere pressure chemical ionization (APCI) mas spectrometry.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2748-2752
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• 2012

Cr(III) and Co(III) complexes with acetylacetonate were anchored onto a mesoporous MCM-41 through Schiff condensation. The materials were characterized by XRD, FT-IR, BET, CHN and ICP techniques. Elemental analysis of samples revealed that one C=N bond was formed through Schiff condensation on MCM-41 surface. The catalysts were tested for the alcohol oxidations using t-butyl hydroperoxide (TBHP) and $H_2O_2$ as oxidant. The catalytic experiments were carried out at both room temperature and reflux condition. Various solvents such as dichloromethane, acetonitrile and water were examined in the oxidation of alcohols. Among the different solvents, catalytic activity is found more in acetonitrile. Further, the catalysts were recycled three times in the oxidation of alcohols and no major change in the conversion and selectivity is observed, which shows that the immobilized metal-acetylacetonate complexes are stable under the present reaction conditions.

• Journal of Environmental Science International
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• v.7 no.4
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• pp.461-466
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• 1998

One hundred and thirty two ground water samples from the Usan area were divided into urban and non-urban groupings and were assessed between 1993 and 1996. The results of statistical analysis were as follows: There were significant differences between the two groupings in the average value of the following water quality parameters: total hardness, nitrate , pH, iron, ammonia and chloride ion in the order of Z-score . Because total hardness, nitrate, and pH were also significant in ANOVA test, these three parameters can be regarded as the most sensitive parameters of artirial pollutants. By the comprehensive com- parison of Ulsan water Quality to that of Kangwon-do, all of the major parameters(pH, KMnO4 consumption, sulfate, chloride and hardness except nitrated were confirmed as being significantly Increased levels.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.372-375
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• 2006

SOFC is a high temperature fuelcell with many advantages, but it also have several demerits. One of the Issues is cathode poisoning of Cr coming from stainless steel interconnects. Diffusion process of Cr evaporated from the surface of interconnect steel was calculated by using CFD technique to understand factors for Cr deposition. It has been cleared that factors concerned in Cr deposition and how they affect Cr deposition. Major variables for Cr deposit ion are diffusion coefficient, air velocity and temperature If diffusion coefficient decreases, Cr concentration increases in the air but decreases on the cathode surface. Increasing in air velocity, Cr concentration decreases in the air and on the cathode surface. Increase in temperature leads to rising Cr concentration on the cathode surface because of diffusion coefficient increment.

• Analytical Science and Technology
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• v.18 no.1
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• pp.35-42
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• 2005

This study reports the effect of $Mg^{2+}$ ions on the behavior of the anionic surfactant in electrophoresis. Intractions of $Mg^{2+}$ ions with carboxylates and sulfonates resulted large changes in their apparent mobilities. A comprehensive analysis of the electroosmotic and electrophoretic mobilities reveals that major cause for the variation of the apparent mobilities of anions arises from the electroosmotic mobilities.