• Tuberculosis and Respiratory Diseases
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• v.41 no.4
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• pp.328-338
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• 1994

Background: Effect of sulfur dioxide($SO_2$) exposure on airway is well known but little about the effect of $SO_2$ exposure on lung parenchyme. This study is to determine if short tenn exposure to $SO_2$ in concentration commonly found in industrialized environment cause potentially harmful effect on the lung parenchyme, and to evaluate the exposure time-response relationship between short tenn exposure to $SO_2$ and the inflammatory response in mouse lung. Method: 5ppm $SO_2$ gas was used and 48 mice were grouped into control(10), 30(9), 60(11), and 120 minute exposure(18) group. In each group, bronchoalveolar lavage(BAL) was done immediately after and at 1,2,3 days after exposure. Histological examination was performed in control and 120 minute exposure group. Results: 1) Cell response in bronchoalveolar lavage fluid. In 30 and 60 minute exposure group, compared to the control group, lymphocyte count has significantly increased(p<0.05) at 1 day after exposure but did not differ at 2 days after exposure. In 120 minute exposure group, also compared to the control group, there was significant increase in total cell, macrophage, and lymphocyte count at 1 day after exposure, (p<0.05) which lasted for 2 days but did not significantly differ at 3 days after exposure. 2) Histological findings in 120 minute exposure group. In the airway, mild epithelial cell damage and ciliary loss were noted but there was no evidence of inflammatory cell infiltration. Interstitial inflammatory infiltration was noted at 1 day after exposure, which lasted for 3 days after exposure and there was no evidence of edema or fibrosis in the interstitium Conclusions: These data indicate potentially noxious effect of $SO_2$ on the lung parenchyme as well as the airway at exposure level that are regarded as relatively safe, and the duration of injury depends on the exposure time.

• Tuberculosis and Respiratory Diseases
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• v.52 no.5
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• pp.529-538
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• 2002

Background : Many clinicians are reluctant to prescribe systemic corticosteroids to manage an asthmatic attack because of many complications such as osteoporosis, cushing's syndrome, diabetes, hypertension and bleeding tendency. The use of nebulized budesonide may be of value in some infants, old men, and in particular adult asthmatic patients who complain of severe dyspnea. A clinical validation and steroid-sparing effect of nebulized budesonide in asthmatic adults and COPD were evaluated, and the short-term effects of budesonide use on the HPA axis were assessed. Materials and Methods : Study A was prospectively done with 41 patients diagnosed with pure asthma and 30 patients diagnosed with COPD (including asthmatic component) in Soonchunhyang Hospital, Chunan from June. 2000 to Sep. 2001. They were treated with nebulized budesonide including systemic steroids (Group 1), a budesonide tubuhaler including a systemic steroid (Group 2), or only the systemic steroid(Group 3). The peak flow rate, arterial blood gas in room air, pulmonary function test, symptom scoring, steroid amount and hospital stay were analyzed. Study B was conducted with 19 patients to evaluate the short-term effects on the HPA axis of treatment with nebulized budesonide 1mg twice daily and a budesonide turbuhaler 5 puffs twice daily. The adrenal function was assessed prior to budesonide inhalation and after 7 days of budesonide inhalation. Results : In the pure asthmatic patients, the mean value of the symptoms (dyspnea, wheezing, cough, night asthma) or the arterial BGAs, total amounts of steroid or hospital stay and the difference in the results of the pulmonary function tests or peak expiratory flow rate were similar in the three groups. In COPD with an asthmatic component, there were no significant differences among the three groups. Although nebulized budesonide suppressed HPA function,(p=0.006) the HPA responses from the nebulized budesonide and turbuhaler budesonide were similar (p=0.288) Conclusion : This result suggests that systemic steroid should only be made available for acute asthmatic patients irrespective of the inhaled budesonides. Nebulized budesonide at the therapeutic dose has similar effects on the HPA axis compared to that of turbuhaler budesonide.

• Journal of Radiation Protection and Research
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• v.36 no.2
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• pp.71-78
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• 2011

Yeong-Gwang N.P.P Private Environment Supervisory Organization analyzed over 3,000 samples including 10 marine and 24 land samples from the year 2,000 to 2009. According to the results of the analysis, artificial nuclides that resulted from the effect of Yeong-Gwang Nuclear Power Plant operations were not detected in most samples. However, from the rain and seawater samples, which were taken from inside the plants such as the intake, the discharge and the observatory, $^3H$ was detected although it was below the regulation level. The $^3H$ concentration detected in the rain taken from the observatory, by the yearly average criterion, was 30.5~40.0 $Bq{\cdot}L^{-1}$, which is around 20 times the $^3H$ concentration detected in the surroundings of the power plants, but it is 0.1% of the regulation level of 40,000 $Bq{\cdot}L^{-1}$. Also, $^3H$ concentration detected in the seawater taken from the intake and the discharge, by the yearly average criterion, was 2.75~17.8$Bq{\cdot}L^{-1}$, which means the concentration detected in the discharge is about 140~280% higher than that detected in the intake except the year 2006. Based on these results, it was determined that, although lower than the regulation level, the $^3H$ in gas and liquid form detected in the rain and seawater sampled from the observatory and the discharge was released into the environment from the power plants. Therefore, regular monitoring and analysis is required on the level of $^3H$ in the observatory and the discharge.

• Progress in Medical Physics
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• v.9 no.4
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• pp.267-276
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• 1998

Any detector inserted into a phantom should have such a geometry that it caused as small as possible perturbation of the electron fluence. Plane parallel chambers meet this requirement better than other chambers of configurations. IAEA protocol recommends the use of plane parallel chambers for this reason. However, the cylindrical chambers are widely used for convenient. The purpose of this study is to evaluate the absorbed dose due to the differences of four different dosimetry protocols such as IAEA protocol using cylindrical chamber, TG 21 protocol using cylindrical chamber, Markus protocol using plane parallel chamber, and TG 39 report for the calibration of plane parallel chamber in electron beams. Depth-ionization measurements for the electron beams of nominal energy 6, 9, 12, 15, and 18 MeV from Siemens accelerator with a 10$\times$10 cm$^2$ field size were made using a radiation field analyser with 0.125 cc ion chamber. Dosimetric measurements by IAEA and TG 21 protocol were made with a farmer type ionization chamber in solid water for each electron energy, respectively. Dosimetric measurements by Markus protocol were made with a plane parallel ionization chamber in solid water for each electron energy, respectively. The cavity-gas calibration factor for the plane parallel chamber was obtained with the use of 18 MeV electron beam as guided by TG 39 report. Dosimetric measurements by TG 39 were performed with a plane parallel ionization chamber in solid water for each electron energy, respectively. For all the energies and protocols, measurements were made along the central axis of the distance of 100 cm (SSD = 100 cm) with 10$\times$10 cm$^2$ field size at the depth of d$_{max}$ for each electron beam, respectively. In the case of 18 MeV, the discrepancy of 0.9 % between IAEA and TG 21 was found and the two protocols were agreed within 0.7 % for other energies. In the case of 18 MeV and 6 MeV, the discrepancies of $\pm$ 0.8 % between Markus and TG 39 was found, respectively and the two protocols were agreed within 0.5 % for other energies. Since the discrepancy of 1.6 % between cylindrical and plane parallel chamber was found for 18 MeV, it is suggested to get the calibration factor using other method as guided. by TG 39.9.

• Journal of Korean Society of Forest Science
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• v.82 no.3
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• pp.271-282
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• 1993

This study was conducted to investigate the absorbing and/or filtering capacity of woody landscape plants growing in urban and industrial regions of Seoul and Taejon. Korea. Total sulfur content and heavy metal content were analyzed in tree foliage of Pinus densiflora, Pinus koraiensis, Ginkgo biloba. Liriodendron tulipifera, Platanus occidentalis. The total sulfur content in the leaves of woody landscape plants in Seoul and Taejon were remarkably higher than those of the tree leaves in Kwangreung. The total sulfur content of deciduous trees had 2.6 times more than that of coniferous trees. the former had better absorbing capacity of $SO_2$ gas. Especially Ginkgo biloba and Platanus occidentalis were recommanded as absorption trees of $SO_2$ because sulfur content levels of them were the highest among all species and increased until tall coloration. While coniferous trees showed no changes in total sulfur content between four seasons. deciduous trees increased in sulfur during the growing season. Pb content of all species in polluted area were higher than those in unpolluted area. In polluted area, while coniferous trees had higher absorption and accumulation of Pb, deciduous trees had higher absorption of Zn. The content of Pb, Zn and Cu in needle of Pinus koraiensis were more than those of Pinus densiflora, In Pinus koraiensis and Pinus densiflora, heavy metal content in the 2nd year needle were higher than thous in the current year needle. In Pinus densiflora, Pinus koraiensis Liriodendron tulipifera and Platanus occidentalis there was a positive correlation between total sulfur and heavy metals [(Pb+Zn+Cu)/3] content.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.227-233
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• 1986

The compositions and seasonal variations of free sugars and non-volatile organic acids of brown algae, such as Ecklonia cava, Sargassum ringgoldianum and Myagropsis myagroides were investigated by gas chromatography. Four kinds of free sugars, such as xylose, glucose, galactose and floridoside were identified. The most abundant one was floridoside marking 118.7 mg/100 g, 90.9 mg/100 g and 70.0 mg/100 g in Ecklonia cava, Sargassum ringgoldianum and Myagropsis myagroides, respectively. There were not distinguishable seasonal variations in the contents of free sugars in all the samples. In the case of organic acids, nine kinds were identified in Ecklenia cava and major ones were succinic, citric, malic, fumaric, oxalic and lactic acid, of which succinic acid was the most abundant one marking $30.6\%$ of total organic acids. In Sargassum ringgoldianum and Myagropsis myagroides, eight kinds were identified, which major ones were succinic, citric and malic acid in both samples, and they marked $68.4\%$ and $61.1\%$ of total organic acids in Sargassum ringgoldianum and Myagropsis myagroides, respectively. There were not distinct changes in the content of total organic acids according to seasons in all the samples examined. The contents of total organic acics in Ecklonia cava was a little more than Sargassnm ringgoldianum and Myagropsis myagroides.

• Journal of the Korean Electrochemical Society
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• v.6 no.1
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• pp.59-64
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• 2003

We fabricated mixed ionic-electronic conducting membranes, $CH_4\;Using\;{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$, by solid state reaction method for solid oxide fuel cell. The membranes consisted of single perovskite phase and exhibited high relative density, $>95\%$. We coated $La_{0.6}Sr_{0.4}CoO_{3-\delta}$ layer using screen printing method in order to improve surface reactivity of the $La_{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$. As a result, the oxygen permeation flux of the coated $La_{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$ showed higher value, $0.5ml/min{\cdot}cm^2\;at\;950^{\circ}C$ than the uncoated one. Higher oxygen permeation was observed in the porously coated Lao $La_{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$membranes with larger grain sizes. Syngas, $CO+H_2$, was successfully obtained from methane gas, $CH_4$, using the $La_{0.6}Sr_{0.4}CoO_{3-\delta}$ coated $La_{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$, with over $40\%\;of\;CH_4$ conversion and syngas yield. $La_{0.7}Sr_{0.3}Ga_{0.6}Fe_{0.4}O_{3-\delta}$ membrane was stable even when it was exposed to the reducing environment, methane, for 600 hrs at $950^{\circ}C$.

• The Journal of Engineering Geology
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• v.21 no.2
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• pp.163-178
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• 2011

A test borehole was drilled in the Cheongwon area to investigate the relationship between geochemical environment and the natural occurrence of radioactive materials (uranium and Rn-222) in borehole groundwater. The borehole encountered mainly biotite schist and biotite granite, with minor porphyritic granite and basic dykes. Six groundwater samples were collected at different depths in the borehole using the double-packed system. The groundwater pH ranges from 5.66 to 8.34, and the chemical type of the groundwater is Ca-$HCO_3$. The contents of uranium and Rn-222 in the groundwater are 0.03-683 ppb and 1,290-7,600 pCi/L, respectively. The contents of uranium and thorium in the rocks within the borehole are 0.51-23.4 ppm and 0.89-62.6 ppm, respectively. Microscope observations of the rock core and analyses by electron probe microanalyzer (EPMA) show that most of the radioactive elements occur in the biotite schist, within accessory minerals such as monazite and limenite in biotite, and in feldspar and quartz. The high uranium content of groundwater at depths of -50 to -70 m is due to groundwater chemistry (weakly alkaline pH, an oxidizing environment, and high concentrations of bicarbonate). The origin of Rn-222 could be determined by analyzing noble gas isotopes (e.g., $^3He/^4He$ and $^4He/^{20}Ne$).

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.452-458
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• 2010

This study aimed at improving the packaging technology of Yukwa to improve the quality and extend the shelflife using secondary packaging. After packaging the Yukwa using an OPP film, P2, P3, and P4 packaging materials were applied secondarily. Various films including (1) P1: OPP (oriented polypropylene), (2) P2: P1+OPP/LLDPE (linear low density polyethylene), (3) P3: P1+PET (polyethylene terephthalate)/NY (nylon)/CPP (cast polypropylene) and (4) P4: P1+PET/AL (aluminum)/NY/CPP (P4) were used for packaging Yukwa. The experiment was conducted at $25^{\circ}C$ for 12 weeks. P1 showed the highest acid value score (1.26 mg KOH/g), and P3 had the highest peroxide value score (32.91 meq/kg) among all packaging groups. Nevertheless, these values did not exceed the guideline values of 2.0 g KOH/g and 40 meq/kg specified in the Korean food code. The overall color difference showed a tendency for decreasing Hunter 'L' values and increasing 'a' and 'b' values; however, no noticeable difference in the outer appearance was observed in any of the packaging treatments except in the P1 for greater than 10 weeks of storage. Some texture defects were observed in the Yukwa when the moisture contents dropped below 5%. The P4 packaging treatment had the lowest moisture permeability and showed the least rheological deterioration change, followed by P3 and P2. In conclusion, the use of a secondary packaging with less gas and moisture permeability was more effective for maintaining the quality and extending the shelf-life of Yukwa than other types of packaging material.

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.383-389
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• 2010

The aim of this study was to determine the methylmercury (MeHg) levels in abyssal fish species. The MeHg in the fishes was extracted with hydrochloric acid and toluene and then purified using an L-cysteine solution. The extract was analyzed with a gas chromatography-electron capture detector (GC-${\mu}ECD$) with a thermon Hg-capillary column. The detection limit and the recovery of the method were 0.002 and 84.2-98.5% (mean, 93.4%), respectively. The MeHg content in 492 abyssal fishes ranged from 0.037 to 2.009 mg/kg. The levels of MeHg [range, mg/kg (mean)] were significantly dependent on fish species and presented as the following; 0.157-2.009 (0.546) in Scalloped hammerhead shark, 0.211-0.878 (0.501) in Blue shark, 0.121-0.993 (0.482) in Spiny dogfish, 0.243-0.658 (0.397) in Salmon shark, 0.074-1.958 (0.353) in Blacktip shark, 0.038-0.807 (0.302) in Southern hake, 0.099-0.511 (0.300) in Scorpion fish, and 0.037-0.133 (0.067) in Ling. The monitoring results showed that the estimated weekly intake of MeHg from sharks, Southern hake, and Ling were lower than the provisional tolerable weekly intake recommended by the Joint FAO/WHO expert committee on food additives.