• Mycobiology
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• v.37 no.4
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• pp.313-316
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• 2009

To determine the optimal medium conditions for the detection of the cellulolytic activity in Ganoderma lucidum, we varied three media conditions: dye reagent, pH, and temperature. First, we evaluated the use of four dyes, Congo Red, Phenol Red, Remazol Brilliant Blue, and Trypan Blue. To observe the effect of pH on the chromogenic reaction, we also made and tested various media spanning acidic and alkaline pHs, ranging from 4.5 to 8.0. Furthermore, in order to research the effect of temperature on the clear zone and the fungus growing zone, we tested temperatures ranging from 15 to $35{^{\circ}C}$. On the whole, the best protocol called for Ganoderma lucidum transfer onto media containing Congo red with pH adjusted to 7.0, followed by incubation at $25{^{\circ}C}$ for 5 days. Our results will be useful to researchers who aim to study extracellular enzyme activity in Ganoderma lucidum.

• Journal of Korean Society on Water Environment
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• v.23 no.3
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• pp.371-376
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• 2007

The features of precipitating reaction of fluorine have been examined under several aquatic conditions by employing calcium ion as a precipitant. Based on MINTEQ program, fluorine was found to exist in the forms of $H_2F_2$ and HF in strong acidic environment and change into $F^-$ with increasing pH. In the experimental condition, the precipitating reaction of fluorine progressed rapidly within a few minutes after the reaction started and reached its equilibrium in 10 minutes. As the addition of precipitant was increased, removal of fluorine by the formation of precipitate was promoted and its was also enhanced by the rise of pH. The precipitating reaction of fluorine was impeded when its initial concentration was low and X-ray analysis showed that the crystalline structure of precipitate was mainly $CaF_2$ with partly NaF. Coexisting phosphate in solution influenced the fluorine removal by impeding the precipitate formation and similar effect was found when metallic ion such as $Zn^{2+}$ was present with fluorine.

• Asian Journal of Atmospheric Environment
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• v.4 no.2
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• pp.72-79
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• 2010

In this study, the ionic composition of volcanogenically derived particles and their temporal and spatial distributions have been investigated to evaluate the impact of the volcanic eruption on the local ecosystem and residents. To this end, an intensive field study was conducted to measure the size-segregated particulate matters at the east part of Sakurajima in Japan. Fractionated sampling of particles into > $PM_{10}$, $PM_{10-2.5}$, and $PM_{2.5}$ was made by a multi nozzle cascade impactor (MCI). The concentration of various ions present in the size-resolved particles was determined by Ion chromatography. The time dependent 3-dimensional Volcanic Ash Forecast Transport And Dispersion (VAFTAD) model developed by the NOAA Air Resources Laboratory (ARL) indicated that the sampling site of this work was affected by the volcanic aerosol particles plume. The temporal distributions of sulfate and $PM_{2.5}$ during the field campaign were significantly variable with important contributions to particle mass concentration. The chlorine loss, suspected to be caused by acidic components of volcanic gases, occurred predominantly in fine particles smaller than $10\;{\mu}m$.

• Journal of Korean Library and Information Science Society
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• v.30 no.1
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• pp.243-255
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• 1999

In modem day Korea, the amount of records containing data, statistic etc are increasing dramatically. However, our country neglects to deal with these archives which include fields such as culture. Thus government documents, even modem documents less than 50 years old, are fading. becoming damaged and acidic. The purpose of this study is to research factors for prolongment the life of archival records, especially papers. Firstly, we want to maintain the document's original quality, which is a PH between 7 to 8.5, permanently. Secondly, our objective is to permanently maintain the records in a scientific environment. Thirdly, to execute proper repair methods by conservators. Permanent quality refers to the maintenance of a PH between 7 and 8.5 in a scientific environment whereby regulations are in effect to control the environment. These factors include constant temperature and humidity, breakors of various lights, Stable storage facilities which are fire resistent. A CCV control system as well as the dusting and fumigation of records. Finally, to conservate damaged papers based on exact diagnosis.

• Journal of Soil and Groundwater Environment
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• v.19 no.1
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• pp.63-69
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• 2014

This paper presents the feasibility of using different iron oxides (microscale hematite (HT), microscale magnetite (MT), and nanoscale maghemite (NMH)) in enhancing nitrate reduction by zero-valent iron (Fe(0)) under two solution conditions (artificial acidic water and real groundwater). Addition of MT and NMH into Fe(0) system resulted in enhancement of nitrate reduction compared to Fe(0) along reaction, especially in groundwater condition, while HT had little effect on nitrate reduction in both solutions. Field emission scanning electron microscopy (FESEM) analysis showed association of MT and NMH with Fe(0) surface, presumably due to magnetic attraction. The rate enhancement effect of the minerals is presumed to arise from its role as an electron mediator that facilitated electron transport from Fe(0) to nitrate. The greater enhancement of MT and NMH in groundwater was attributed to surface charge neutralization by calcium and magnesium ions in groundwater, which in turn facilitated adsorption of nitrate on Fe(0) surface.

• Journal of the Korean Wood Science and Technology
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• v.48 no.5
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• pp.641-650
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• 2020

In this study, the chemical components and termiticidal activities of bamboo vinegar against subterranean termite were evaluated. Bamboo vinegar used in this study were produced from Mayan (Gigantochloa robusta Kurz.), Balcoa (Bambusa balcooa Roxb.), and Taiwan (Dendrocalamus latiflorus Munro). It was analyzed by gravimetric methods. Rubberwood (Hevea brasiliensis) was soaked for 24 h and tested against Coptotermes curvignathus Holmgren according to the Indonesian National Standard (SNI 7207-2014). The bamboo vinegar demonstrated antitermite activities against subterranean termite. Vinegar of 400℃ recorded higher total phenol and acid than that of 300℃. Results from this study suggest that the phenolic and acidic component of the bamboo vinegar contributed to 100% mortality rate of the termite, some wood weight loss, and a decrease in the termite feeding rate. These results strongly recommend that bamboo vinegar from D. latiflorus Munro is a potential environmentally friendly preservative.

• Journal of Microbiology and Biotechnology
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• v.33 no.2
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• pp.180-187
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• 2023

The skin is a dynamic ecosystem on which diverse microbes reside. The interkingdom interaction between microbial species in the skin microbiota is thought to influence the health and disease of the skin although the roles of the intra- and interkingdom interactions remain to be elucidated. In this context, the interactions between Malassezia and Staphylococcus, the most dominant microorganisms in the skin microbiota, have gained attention. This study investigated how the interaction between Malassezia and Staphylococcus affected the antifungal susceptibility of the fungus to the azole antifungal drug ketoconazole. The susceptibility was significantly decreased when Malassezia was co-cultured with Staphylococcus. We found that acidification of the environment by organic acids produced by Staphylococcus influenced the decrease of the ketoconazole susceptibility of M. restricta in the co-culturing condition. Furthermore, our data demonstrated that the significant increased ergosterol content and cell membrane and wall thickness of the M. restricta cells grown in the acidic environment may be the main cause of the altered azole susceptibility of the fungus. Overall, our study suggests that the interaction between Malassezia and Staphylococcus influences the antifungal susceptibility of the fungus and that pH has a critical role in the polymicrobial interaction in the skin environment.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.135-143
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• 2008

The ratio between 11S Sand 7S globulins was greater in large seed size varieties (LSSVs) of soybean than in small seed size varieties (SSSVs) or medium seed size varieties (MSSVs) but did not differ between MSSVs and SSSVs. The cysteine and methionine contents of 11S globulins were greater than those of total seed proteins and 7S globulins. The acidic monoamino monocarboxylic amino acids were the most abundant class of amino acid in soybean seed (27.2%) and soybean curd protein (29.3%). Isolated 7S and 11S fractions were analyzed by HPLC. Of the 12 peaks detected, 4 constituted 64.1% of the proteins of the SSSVs, 65.6% of the proteins of the MSSVs, and 70.5% of the proteins of the LSSVs. The 11S/7S globulin ratio was related to the yield and hardness of soybean curd. The MSSVs had the greatest yield of soybean curd, but the soybean curd hardness of the MSSVs was greater than that of the SSSVs. These results show that the 11S/7S ratio and color of soybean seeds can be used to predict the yield, hardness, and color of soybean curd.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.1
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• pp.71-76
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• 2008

CuFeOx/$Al_2O_3$ catalysts are developed for the use in sulfuric acid decomposition which is a subcycle in thermochemical iodine-sulfur cycle to split water into hydrogen and oxygen. Both Cu and Fe components are co-precipitated with Al component to enhance distribution of active components. Developed catalysts are improved in the capability of sulfuric acid decomposition and endurance under highly acidic environment compared to commercial catalysts such as Pt/$Al_2O_3$ and $2CuO{\cdot}Cr_2O_3$. Developed CuFeAlOx catalysts exhibited higher sulfuric acid decomposition ability than $2CuO{\cdot}Cr_2O_3$ and longer endurance trends than Pt/$Al_2O_3$ maintaining comparable performance, respectively.

• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1476-1484
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• 2023

Laboratory experiments and point monitoring of reservoir sediments have proven that stable sulfate reduction (SSR) can lower the concentrations of toxic metals and sulfate in acidic groundwater for a long time. Here, we hypothesize that SSR occurred during in situ leaching after uranium mining, which can impact the fate of acid groundwater in an entire region. To test this, we applied a sulfur isotope fractionation method to analyze the mechanism for natural attenuation of contaminated groundwater produced by acid in situ leaching of uranium (Xinjiang, China). The results showed that δ³⁴S increased over time after the cessation of uranium mining, and natural attenuation caused considerable, area-scale immobilization of sulfur corresponding to retention levels of 5.3%-48.3% while simultaneously decreasing the concentration of uranium. Isotopic evidence for SSR in the area, together with evidence for changes of pollutant concentrations, suggest that area-scale SSR is most likely also important at other acid mining sites for uranium, where retention of acid groundwater may be strengthened through natural attenuation. To recapitulate, the sulfur isotope fractionation method constitutes a relatively accurate tool for quantification of spatiotemporal trends for groundwater during migration and transformation resulting from acid in situ leaching of uranium in northern China.