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        검색결과 16

        1.
        2016.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The following study aims to estimate the configuration ratio of the ion compounds that identifies the cause of fine dust and ways to reduce it. In this study, the physical and chemical properties of fine particles in a tunnel and the configuration form of ionic composition were interpreted to establish reasonable measurement for air quality management. Seasonal measurements were performed by collecting samples from the Mia sageori subway station. Chemical Mass Balance (CMB) model was used to estimate the configuration ratio of ions in this study. The results showed that the test performed outside showed about 56.4% of total ion, with (NH4)2SO4, NH4NO3, CaCO3 and NaCl showing concentrations of 2.138 μg/m3, 1.957 μg/m3, 1.697 μg/m3 and 1.600 μg/m3, respectively, while the results indoor had CaCO3, NH4NO3, (NH4)2SO4 and NaCl showing concentrations of 2.272 μg/m3, 2.204 μg/m3, 1.656 μg/m3 and 1.342 μg/m3, respectively, about 65.1% of total ion. During the usage of tunnel, it was found that CaCO3, NH4NO3, (NH4)2SO4 and MgCO3 showed concentrations of 3.464 μg/m3, 1.732 μg/m3, 1.698 μg/m3 and 0.582 μg/m3, respectively, total ion of 70.2% was presented.
        4,000원
        2.
        2003.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 양이온교환막 표면에 형성된 바이폴라 계면이 물분해 현상에 미치는 영향을 조사하였다. 실험결과, 전기투석 중 막표면에 형성된 고정화된 바이폴라 계면이 심각한 물분해를 유발함을 알 수 있었다. 특히, 고정화된 바이폴라 계면은 다가 양이온이 전해질로 이용되는 전기투석 시스템에서 양이온교환막 표면에 쉽게 형성됨을 알 수 있었다. 낮은 용해도적 상수를 갖는 다가 양이온들은 급격한 물분해를 유발하였는데 이는 이들이 막표면에서 쉽게 수산화물의 형태로 침적되며 따라서 수소-친화 그룹과 수산화-친화 그룹으로 구성된 바이폴라 계면이 막-용액 계면에 형성됨을 알 수 있었다. 따라서 물분해는 막 표면의 금속수산화물 층과 막의 고정전하 그룹간에 발생되는 강한 전기장에 의해 크게 활성화됨을 알수 있다. 또한 이와 유사하게 분자량이 큰 유기 상대이온들이 막표면에 누적되는 경우에도 고정화된 바이폴라 계면이 형성되어 한계전류밀도 이상에서 심각한 물분해를 유발하였다. 따라서 전기투석의 고전류 운전시 효율 향상을 위해서는 막표면에 유발되는 고정화된 바이폴라 계면의 형성을 억제하는 것이 매우 중요함을 알 수 있다.
        4,200원
        4.
        2000.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Thymus속의 common thyme과 thyme의 담액수경 재배시 배양액의 이온농도를 달리하여 두 종의 생육과 품질을 비교하였다. 배양액의 이온농도는 1.2, 2.4, 4.8 그리고 7.2mS.cm-1로 하였다. 두 종 모두 0.5(EC=1.2 mS.cm-1)배와 1배의 낮은 이온농도 처리에서 생육이 좋았다. Common thyme과 lemon thyme의 생육은 배양액내 이온농도가 높아질수록 건물율은 증가했으나 초장, 근장과 생체중은 감소하였다. 엽록소 함량은 lemon thyme에서 더 높았으나 비타민 C의 함량과 정유함량은 common thyme에서 더 높았다. 두 종간의 주요 정유 성분 차이를 보면, common thyme의 주성분은 thymo과 carvacrol이고, lemon thyme은 geranio과 α-citral로 각각 정유 성분의 50~70%를 차지하고 있다. 이들의 각 주성분의 함량은 생육이 좋았던 0.5배에서 가장 많았다. 결과적으로 수경재배시 common thyme과 lemon thyme 모두 허브 배양액 0.5배액으로 재배시 우수한 품질의 작물을 생산할 수 있었다.
        4,000원
        5.
        2022.06 KCI 등재 서비스 종료(열람 제한)
        This study investigated characteristics of meteorological parameters and ionic components of PM2.5 during Asian dust events on November 28 and 30, 2018 at Busan, Korea. The seasonal occurrence frequencies of Asian dust during 1960∼2019 (60 years) were 81.7% in spring, 12.2% in winter, and 6.1% in autumn. Recently, autumn Asian dust occurrence in Busan has shown an increasing trend. The result of AWS (automatic weather station), surface weather chart, and backward trajectory analyses showed that the first Asian dust of Nov. 28, 2018, in Busan came with rapid speed through inner China and Bohai Bay from Mongolia. The second Asian dust of Nov. 30, 2018, in Busan seems to have resulted from advection and deposition of proximal residual materials. These results indicated that understanding the characteristics of meteorological parameters and ionic components of PM2.5 during Asian dust events could provide insights into establishing a control strategy for urban air quality.
        6.
        2021.06 KCI 등재 서비스 종료(열람 제한)
        This research investigated the characteristics of fine particle concentration and ionic elements of PM2.5 during sea breeze occurrences during summertime in Busan. The PM10 and PM2.5 concentrations of summertime sea breeze occurrence days in Busan were 46.5 ㎍/㎥ and 34.9 ㎍/㎥, respectively. The PM10 and PM2.5 concentrations of summertime non-sea breeze occurrence days in Busan were 25.3 ㎍/㎥ and 14.3 ㎍/㎥, respectively. The PM2.5/PM10 ratios of sea breeze occurrence days and non-sea breeze occurrence days were 0.74 and 0.55, respectively. The SO4 2-, NH4 +, and NO3 - concentrations in PM2.5 of sea breeze occurrence days were 9.20 ㎍/㎥, 4.26 ㎍/㎥, and 3.18 ㎍/㎥ respectively. The sulfur oxidation ratio (SOR) and nitrogen oxidation ratio (NOR) of sea breeze occurrence days were 0.33 and 0.05, respectively. These results indicated that understanding the fine particle concentration and ionic elements of PM2.5 during sea breeze summertime conditions can provide insights useful for establishing a control strategy of urban air quality.
        7.
        2017.06 KCI 등재 서비스 종료(열람 제한)
        This research investigates the characteristics of metallic and ionic elements in PM10 and PM2.5 on haze day and non-haze day in Busan. PM10 concentration on haze day and non-haze day were 85.75 and 33.52 ㎍/m³ , respectively, and PM2.5 on haze day and non-haze day were 68.24 and 23.86 ㎍/m³ , respectively. Contribution rate of total inorganic water-soluble ion to PM10 mass on haze day and non haze day were 58.2% and 61.5%, respectively, and contribution rate of total water-soluble ion to PM2.5 mass on haze day and non haze day were 58.7% and 64.7%, respectively. Also, contribution rate of secondary ion to PM10 mass on haze day and non haze day were 52.1% and 47.5%, respectively, and contribution rate of secondary ion to PM2.5 mass on haze day and non haze day were 54.4% and 53.6%, respectively. AC (anion equivalents)/CE (cation equivalents) ratio of PM10 mass on haze day and non haze day were 1.09 and 1.0, respectively, and AC/CE ratios of PM2.5 mass on haze day and non haze day were 1.12 and 1.04, respectively. Also, SOR (Sulfur Oxidation Ratio) of PM10 mass on haze day and non haze day were 0.32 and 0.17, respectively, and SOR of PM2.5 on haze day and non haze day were 0.30 and 0.15, respectively. Lastly, NOR (Nitrogen Oxidation Ratio) of PM10 on haze day and non haze day were 0.17 and 0.08, respectively, and NOR of PM2.5 on haze day and non haze day were 0.13 and 0.06, respectively.
        8.
        2016.06 KCI 등재 서비스 종료(열람 제한)
        In this study, mass concentrations and chemical compositions of PM2.5, including water-soluble ions and elements were determined at the 1,100 m-highland of Mt. Hallasan in Jeju Island across four seasons from August 2013 to August 2014. The average mass concentration of PM2.5 was 12.5±8.41 /m3 with 45.8% of the contribution from eight water-soluble ionic species. Three ionic species (SO4 2-, NH4 +, and NO3 -) comprised 96.2% of the total concentration of ions contained in PM2.5 and were the dominant ions, accounting for 43.5% of the PM2.5 mass at Mt. Hallasan. On the basis of the mass concentration level, seasonal variation, enrichment factor, and relationship among elements, we can presume that Mg, K, Ca, Mn, Fe, Co, Sr, Ba, Nd, and Dy originated mainly from crust or soil and that V, Cr, Ni, Cu, Zn, As, Cd, and Pb were significantly enriched in PM2.5 owing to the effects of the anthropogenic emissions. These results and the local distribution of emission sources and topographic characteristics near this sampling site suggest that the compositions of PM2.5 collected at the 1100 m-highland of Mt. Hallasan were largely influenced by inflow from outside of Jeju Island.
        9.
        2016.05 KCI 등재 서비스 종료(열람 제한)
        This study investigates the characteristics of metallic and ionic elements concentration, concentration according to transport path, and factor analysis in PM10 at Guducsan in Busan in the springtime of 2015. PM10 concentration in Guducsan and Gwaebeopdong were 59.5± 9.04 ㎍/㎥ and 87.5±20.2 ㎍/㎥, respectively. Contribution rate of water-soluble ions and secondary ion in PM10 concentration in Guducsan were 37.0% and 27.8% respectively. [NO3 -/SO4 2-] ratio and contribution rate of sea salt of PM10 in Guducsan and Gwaebeopdong were 0.91 and 1.12, 7.0% and 5.3%, respectively. The results of the backward trajectory analysis indicates that PM10 concentration, total inorganic water-soluble ions and total secondary ions were high when the air parcels moved from Sandong region in China than non-Sandong and northen China to Busan area. The results of the factor analysis at Guducsan indicates that factor 1 was anthropogenic source effects such as automobile emissions and industrial combustion processes, factor 2 was marine sources such as sea salts from sea, and factor 3 was soil component sources.
        10.
        2015.06 KCI 등재 서비스 종료(열람 제한)
        This study investigates weekday/weekend characteristics of PM10 concentration and chemical composition of water-soluble ions in Busan in the spring of 2013. Contribution rate of water-soluble ions to PM10 concentration in weekday/weekend were 41.5% and 38.5%, respectively. Contribution rate of SO4 2- to total ion mass in weekday/weekend were 30.4% and 33.8%, respectively. Contribution rate of total inorganic water-soluble ions in PM10 in weekday/weekend were 42.2% and 39.1% (mean 41.4%), respectively. [NO3 -/SO4 2-] ratio in weekday/weekend were 1.01 and 0.97(mean 0.99), respectively, which indicated that weekday ratio was higher. Contribution rate of sea salts and Cl-/Na+ ratio in PM10 in weekday/weekend were 8.1% and 7.6%, 0.37% and 0.41%, respectively. This research will help understand chemical composition of water-soluble ions during the weekday/weekend and will be able to measure the contribution level of artificial anthropogenic source on urban air.
        11.
        2011.01 KCI 등재 서비스 종료(열람 제한)
        The objectives of this study were to investigate the seasonal characteristics of metallic and ion elements of PM10(Particulate matter with aerodynamic diameter ≤10 ㎛) and the effects of vessels exhaust emission from ships harboring in Busan City. The PM10 samples were collected from January 2010 to October 2010 at Dongsam-dong(coastal area), in Busan City. The particulate matters were analyzed for major water soluble ionic components and metals. The ranges of the PM10 mass concentrations were from 29.8 ㎍/㎥ to 47.0 ㎍/㎥ in Dongsam-dong. The PM10 mass concentrations in Dongsam-dong are very similar to Gwangbok-dong during same sampling periods. These results were understood by the effects of the shipping source emitted from ships anchoraging and running. The concentrations of water-soluble ions and metals in the PM10 had a level of as high as the order of SO4 2- >NO3 - >Cl - and NH4 + >Na + >Ca 2+ >K + >Mg 2+ , respectively. The correlation coefficients(R 2 ) for SO4 2- /PM10 and NH4 + /PM10 of were 0.7446 and 0.7784, respectively, and it showed the high correlation with each other.
        12.
        2004.12 KCI 등재 서비스 종료(열람 제한)
        Atmospheric particulate matters were collected by 8-stage non viable cascade impactor from October 2002 to August at Jeju City. Eight water-soluble ionic components (Na+, NH4+, K+, Ca2+, Mg2+, Cl-, NO3- and SO42-) were analyzed by Ion Chromatography. The concentration of particulate matters and eight water-soluble ionic components were determined to investigate their size distributions. Particulate matters exhibited a tri-modal distribution with peak value around 0.9, 4.0㎛ and 9.5㎛. In summer, the last peak value was lower than other season values likely due to particulate matter scavenged by rain water. Four ionic components (Na+, Ca2+, Mg2+ and Cl-) exhibited a bi-modal distribution in the coarse mode whereas three ionic components (NH4+, K+ and SO42-) in the fine mode, with maximum peak value around 0.9㎛. NO3- was found in both the coarse and the fine mode. The enrichment factor (E.F.) of each ionic components was calculated. Based upon E.F., it is considered that Na+, Cl-, and K+ in coarse paricle mode were delivered form oceanic source, but other components might have other source origins.
        14.
        2003.12 KCI 등재 서비스 종료(열람 제한)
        This study was compared each ingredient's local/seasonal change characteristics by analyzing anions and cations, watersoluble ionic components, from the precipitation of Dangjin and Anmyeon-do areas. The samples were collected for 8 months from both spots between the period of April 1, 2002 to November 31, 2002. The precipitation samples were collected continuously through the entire duration of precipitation by using the wet-only automatic samplers. When rain continues to fall over 24 hours or occasionally, we considered those collected from 9 o'clock in the morning for 24 hours as the day's samples. As a method to verify for the reliability of the analyzed data is concerned, we use the ion balance method and the electricity conductance method, was used widely as a way of watching the atmosphere by the WMO (World Meteorological Organization)/GAW (Global Atmosphere Watch). Also, Dangjin and Anmyun-do area confirmed that contains artificial pollutants by analysis of ion concentration data.
        15.
        2003.03 KCI 등재 서비스 종료(열람 제한)
        An agricultural land application of swine slurry is one of the best management practices in Jeju island whose ground water must be protected. So as to study the effect of appling swine slurry on ground water or aquifer, incubation-leaching technique was used by assuming the incubating period of 1, 2, 4, 8, 16, or 32 days, and application rate of 3200.0㎎T-N/ℓ, 820.0㎎T-P/ℓ, and 1887.0㎎K+/ℓin swine slurry. The leachates were collected from the soil columns(PVC 30cmL×5.5cmD) packed 15cm in depth with Gangjeong soil series by washing with 100mL distilled water. The leached components were measured by using Ion chromatography for Cl-, NO3-N, F-, Br-, Na+, K+, Ca2+, and Mg2+, atomic absorption spectrophotometry for Fe and Mn, and UV-Vis spectrophotometry for T-N and T-P. Application of swine slurry in naked soil could influence on the ground water or aquifer by increasing nitrate-nitrogen in leachate with time, or leaching the cations present in soils in accompany with anions because of H+ produced in nitrification. Therefore, careful consideration should be taken about what amount, when, where, and how for protecting ground water system.
        16.
        1998.12 KCI 등재 서비스 종료(열람 제한)
        The adsorption of Cs-137 and Sr-90 onto kaolinite in prescence of major groundwater cations (Ca2+, K+, Na+) with different concentrations was simulated by using triple-layer surface complexation model (TL-SCM). The site density (8.73 sites/nm2) of kaolinite used for TL-SCM was calculated from it's CEC and specific surface area. TL-SCM modeling results indicate that concentrations dependence on 137Cs and 90Sr adsorption onto kaolinite as a function of pH is best modeled as an outer-sphere surface reaction. This suggests that Cs+ and Sr2+ are adsorbed at the β-layer in kaolinite-water interface where the electrolytes, Nacl, KCl and CaCl2, bind. However, TL-SCM results on Sr adsorption show a discrepancy between batch data and fitting data in alkaline condition. This may be due to precipitation of SrCO3 and complexation such as SrOH+. Intrinsic reaction constants of ions obtained from model fit are as follows: Kintcs=10-2.10, KintSr=10-2.30, KintK=10-2.80, KintCa=10-3.10 and KintNa=10-3.32. The results are in the agreement with competition order among groundwater ions (K+〉Ca2+〉Na+) and sorption reference of nuclides (Cs-137〉Sr-90) at kaolinite-water interface showed in batch test.