• Environmental Engineering Research
• /
• v.19 no.1
• /
• pp.101-105
• /
• 2014

Three magnesium compounds, $MgO_2$, MgO, and $Mg(OH)_2$, which are supposed to supply oxygen continuously, were applied onto contaminated bay sediment and its ecology in order to activate the local microbial flora. Those compounds were found to reduce chemical oxygen demand (COD), total nitrogen (T-N), and total phosphorus (T-P). Magnesium oxide, in particular, reduced COD by 30% and T-N and T-P considerably. All compounds also suppressed the release of pollutants in the order $MgO_2$, MgO, and $Mg(OH)_2$. Analysis of microbial flora showed that the microbial group treated by $MgO_2$ and $Mg(OH)_2$ was predictably stable; meanwhile, that treated by MgO increased the number of species, but decreased the total number of microorganisms.

• Journal of Korean Society of Water and Wastewater
• /
• v.20 no.6
• /
• pp.849-855
• /
• 2006

Taste and odor (T&O) problems in drinking water supplies caused by eutrophication have become increasingly important because aesthetic qualities are the primary measures by which consumers estimate the quality of their drinking water. In order to overcome T&O problem, it is necessary to early detection method for T&O compounds before these compounds enter to water treatment plant. In this background, a early waming device for T&O compounds was developed and its performance tested under different operating condition. According to the experimental results on the adsorption efficiency of T&O compounds, when the raw water flowrate was 5 mL/min, the optimum stripping time and air flowrate were 5 hrs and 0.5 L/min, respectively. Comparison of activated carbon showed that foreign activated carbon was better than domestic activated carbon in terms of adsorption efficiency.

• Journal of Environmental Health Sciences
• /
• v.32 no.4 s.91
• /
• pp.262-267
• /
• 2006

DBPs and T&O(taste-and-odor) compounds in drinking water is one of main source to deteriorate water quality. So, these compounds can cause adverse health effects and result in many consumer complaints aesthetically. This experiments carried out to investigate the effect of boiling water on DBPs and T&O compounds in the tap water. THMs and TCM concentration were reduced by 91.3%, 88.9% after 5 min of boiling, respectively. It is certainly, resulted from volatilization of TCM. TCAA concentration decreased when the water was boiled, too. By contrast, the concentration of DCAA was increased with duration time from boiling-point. The reduction of TCAA from the boiled water can be attributed to chemical transformation like decarboxylation. T&O compounds such as geosmin and 2-MIB was effectively removed by boiling of water, resulting in the removal efficiency of 97.1%, 94.4% after 5 min of boiling, respectively.

• Journal of Korean Society of Water and Wastewater
• /
• v.20 no.5
• /
• pp.719-726
• /
• 2006

Adsorption isotherms and kinetics for taste and odor (T&O) compounds and natural organic matters (NOMs) were performed to evaluate the impacts of activated carbon particle size on coagulation and adsorption. Adsorption capacities for iodine, T&O compounds, and NOM of all the activated carbons under #325 mesh were more excellent than those of virgin activated carbons. Small activated carbon particles were more rapidly adsorbed low molecular weight T&O compounds in the water, while those were slowly adsorbed high molecular weight NOM. When the activated carbon and alum were added simultaneously, the adsorption capacity for organics was better than alum was added alone.

• Journal of Korean Society on Water Environment
• /
• v.24 no.5
• /
• pp.598-602
• /
• 2008

The Daecheong Reservoir is the largest multi-purpose reservoir in the Keum River basin. This water supply is subject to some of the most serious taste and odor (T&O) problems in the region. The intensity of T&O events increased due to eutrophication during the 1990s. In this study, the temporal occurrence of T&O in raw water from the main Daecheong Reservoir and its regulating reservoir was compared using both an instrumental method (CLSA+GC/MS) and threshold odor number (TON) test from April to December 2006. In addition, biofilms on the submerged macrophytes and rocks were analyzed for two typical T&O causing compounds, Geosmin and 2-MIB. The maximum concentration of Geosmin in the main reservoir was almost two times higher than that in the regulating reservoir. Interestingly, 2-MIB was only detected in water samples from the main reservoir. In the case of T&O causing compounds present in the biofilm on the submerged macrophytes and rocks, the regulating reservoir had lower concentrations compared to those of the main reservoir. It was found that both Geosmin and 2-MIB were detected from the biofilms much earlier than from the water samples. This result suggests that the occurrence of T&O compounds in the biofilms could be used as an early warning indicator of an imminent T&O outbreak in the water body.

• Natural Product Sciences
• /
• v.15 no.4
• /
• pp.192-197
• /
• 2009

Chemical investigation of the aerial parts of Artemisia iwayomogi has afforded five glycoside compounds. Their chemical structures were characterized by spectroscopic methods to be turpinionoside A (1), (Z)-3-hexenyl O-${\alpha}$-arabinopyranosyl-(1${\rightarrow}$6)-O-${\beta}$-D-glucopyranoside (2), (Z)-5'-hydroxyjasmone 5'-O-${\beta}$-Dglucopyranoside (3), (-)-syringaresinol-4-O-${\beta}$-D-glucopyranoside (4), and methyl 3,5-di-O-caffeoyl quinate (5). All of them were isolated for the first time from Artemisia species. The effect of compounds 1 - 5 on the function of osteoblastic MC3T3-E1 cells was examined by checking the cell viability, alkaline phosphatase (ALP) activity, collagen synthesis, and mineralization. Turpinionoside A (1) significantly increased the function of osteoblastic MC3T3-E1 cells. Cell viability, ALP activity, collagen synthesis, and mineralization were increased up to 117.2% (2 ${\mu}M$), 110.7% (0.4 ${\mu}M$), 156.0% (0.4 ${\mu}M$), and 143.0 % (2 ${\mu}M$), respectively.

• Current Applied Physics
• /
• v.18 no.11
• /
• pp.1280-1288
• /
• 2018

In this work, we pointed out that Sr substitution for Ca leads to modify the magnetic and magnetocaloric properties of $Pr_{0.7}Ca_{0.3-x}Sr_xMnO_3$ compounds. Analyzing temperature dependence of magnetization, M(T), proves that the Curie temperature ($T_C$) increased with increasing Sr content (x); $T_C$ value is found to be 130-260 K for x = 0.0-0.3, respectively. Using the phenomenological model and M(T,H) data measured at several applied magnetic field, the magnetocaloric effect of $Pr_{0.7}Ca_{0.3-x}Sr_xMnO_3$ compounds has been investigated through their temperature and magnetic field dependences of magnetic entropy change ${\Delta}S_m$(T,H) and the change of the specific heat change ${\Delta}C_P$(T,H). Under an applied magnetic field change of 10 kOe, the maximum value of $-{\Delta}S_m$ is found to be about $3J/kg{\cdot}K$, and the maximum and minimum values of ${\Delta}C_P$(T) calculated to be about ${\pm}60J/kg{\cdot}K$ for x = 0.3 sample. Additionally, the critical behaviors of $Pr_{0.7}Ca_{0.3-x}Sr_xMnO_3$ compounds around their $T_C$ have been also analyzed. Results suggested a coexistence of the ferromagnetic short- and long-range interactions in samples. Moreover, Sr-doping favors establishing the short-range interactions.

• Proceedings of the PSK Conference
• /
• 2002.10a
• /
• pp.368.2-368.2
• /
• 2002

Fruits of Hovenia dulcis T. (Rhamnaceae) was called ′jiguja ′ in oriental medicine which has been used for diuresis, remove of hangover and leaves has been used for detoxified the alcohol. From the MeOH Extraction. five compounds were isolated by column chromatography and elucidated as quercetin quercetin-3-O-rhamnose. quercetin-3-O-gal(6"1") rha, quercetin-3-O-glc(6"${\rightarrow}$1")glc, and kaemferol through specroscopic methods. (omitted)

• Biomedical Science Letters
• /
• v.17 no.1
• /
• pp.39-45
• /
• 2011

In the present study, we investigated whether volatile organic compounds induce inflammatory response in human T lymphocytes by evaluating the alteration of inflammatory cytokines. Volatile organic compounds such as formaldehyde, o-xylene, benzene, and hydroquinone have no cytotoxic effects on Jurkat T cells at a high concentration of 50 ${\mu}M$ for 48 h. IL-2, IL-4, IL-13, TNF-${\alpha}$ and IFN-${\gamma}$ were increased after the treatment with volatile organic compounds, although alteration of cytokines is different among volatile organic compounds. LPS as a positive control increased the secretion of IL-2, IL-4, IL-13, TNF-${\alpha}$ and IFN-${\gamma}$. MCP-1 and CCL17 (thymus and activation-regulated chemokine, TARC) were weakly increased after the treatment with volatile organic compounds but the amount of the increased cytokine was below 20 pg/ml. These results suggest that the measurement of cytokine in Jurkat T cells may be used as a useful method for evaluating the toxicity of volatile organic compounds in immune response.

• Journal of the Korean Magnetics Society
• /
• v.21 no.2
• /
• pp.56-60
• /
• 2011

Optical properties of $T_{0.2}Fe_{2.8}O_4$ (T = V, Cr, Mn) thin films derived from ferrimagnetic $Fe_3O_4$ were investigated by spectroscopic ellipsometry in the 1~8 eV photon-energy range. The difference in optical-absorption spectrum between the ternary compounds and $Fe_3O_4$ was analyzed based on preferable sites in spinel structure and iconicity of the doped V, Cr, and Mn ions. The observed absorption spectra from $Fe_3O_4$ and the ternary compounds can be interpreted as mainly due to charge-transfer transitions of Fe d electrons characterized by absorption structures with wide energy width. Also, the observed absorption structures with narrow energy width can be interpreted as due to crystal-field transitions between different d electron configurations of tetrahedral $Fe^{3+}(d^5)$ ion. The transitions were described in terms of spin-polarized electronic states of $Fe_3O_4$.