• Title/Summary/Keyword: Major ion analysis

Search Result 211, Processing Time 0.029 seconds

Artificial and Biological Particles in the Springtime Atmosphere

  • Ma, Chang-Jin;Kim, Ki-Hyun
    • Asian Journal of Atmospheric Environment
    • /
    • v.7 no.4
    • /
    • pp.209-216
    • /
    • 2013
  • This study focused on a comprehensive and detailed interpretation for the springtime air quality influenced by both artificial (particulate matter (PM) and asbestos) and biological (pollen) sources in Fukuoka Prefecture, Japan. An intensive measurement of PM was conducted at four characteristic sites (i.e., a heavy traffic area, a residential area, an industrial area, and a desolate area) in the Fukuoka Prefecture during spring of 2007. Analysis of major ionic species in $PM_{2.5}$ was performed by an Ion Chromatography, and asbestos and pollen were identified by Scanning Electron Microscopy with an energy dispersive X-ray spectrometer (EDX). $PM_{2.5}$ concentration ($65.3{\mu}gm^{-3}$) measured in an industrial area (site C) was extraordinarily high compared to those monitored in other areas; it greatly exceeded the Japan's $PM_{2.5}$ criteria (a daily average of $35{\mu}gm^{-3}$). NOAA's HYSPLIT dispersion model suggests that this high level of $PM_{2.5}$ monitored at site C is unlikely to affect the Asian continent. The ambient concentrations of $PM_{2.5}$-related anions ($NH_4{^+}$, $NO_3{^-}$, and $SO_4{^{2-}}$) and their relative contributions to $PM_{2.5}$ were also investigated in four study areas. The concentrations of these major water-soluble ions exhibit not only strong spatial dependence but also different ratios to each other. Asbestos fiber (crocidolite and amosite) concentration values changed in the range of 2.5 to 14.4 f per liter of air. The number of pollen grains showed that Cedar ranked higher in concentration than other types of pollen, with the maximum concentration at site A.

Analytical Method for Triazine Herbicide Cyanazine Residues in Major Medicinal Crops (주요 약용작물에 대한 Cyanazine 제초제의 잔류 분석법)

  • Hwang, Young Sun;Lim, Jung Dae;Choung, Myoung Gun
    • Korean Journal of Medicinal Crop Science
    • /
    • v.24 no.3
    • /
    • pp.237-245
    • /
    • 2016
  • Background: Cyanazine is used as a pre-emergent herbicide once during the growing season to control weeds of many upland crops worldwide. This study aimed to establish a method to determined cyanazine residue levels in major medicinal crops by using high performance liquid chromatography-UV detection/mass spectometry (HPLC-UVD/MS). Methods and Results: Cyanazine residue was extracted with acetone from the raw products of four representative medicinal plants - Scutellaria baicalensis, Paeonia lactiflora, Platycodon grandiflorum and Angelica gigas. The extract was diluted with a large volume of saline water and directly partitioned into dichloromethane to remove polar co-extractives in the aqueous phase. It was then purifined using optimized Florisil column chromatography. HPLC analysis conducted using an octadecylsilyl column allowed the successful separation of cyanazine from co-extractives of the samples, and the amount was sensitively quantified by ultraviolet absorption at 225 nm with no interference. The accuracy and precision of the proposed method were validated by conducting recovery experiments on each medicinal crop sample fortified with cyanazine at two concentration levels per crop in triplicate. Conclusions: The mean recoveries ranged from 91.2% to 105.3% for the four representative medicinal crops. The coefficients of variation were less than 10%, irrespective of the sample types and fortification levels. The limit of quantification of cyanazine was 0.02 mg/kg as verified by the recovery experiment. A confirmatory method was performed by liquid chromatography/MS using selected-ion monitoring technique to clearly identify the suspected residue.

Modeling of Chloride Ingress in Reinforced Concrete Structures (철근 콘크리트 구조물의 염소이온 침투 모델)

  • Koo, Hyun-Bon;Kim, Eui-Tae;Lee, Kwang-Myong
    • Journal of the Korea Concrete Institute
    • /
    • v.15 no.1
    • /
    • pp.25-34
    • /
    • 2003
  • The degradation of reinforced concrete (RC) structures due to physical and chemical attacks has been a major issue in construction engineering. Deterioration of RC structures by chloride attack followed by reinforcement corrosion is one of the serious problems. An objective of this study is to develop a form of mathematical model of chloride ingress into concrete. In order to overcome some limits of the previous approaches, a chloride ingress model, consisting of chloride solution intrusion through the capillary pore and chloride ion diffusion through the pore water, was proposed. Moreover, the variability of chloride ion diffusivity due to the degree of hydration of cement, relative humidity in pore, exposure condition, and variation of chloride binding, was considered in the model. In order to verify the proposed model, the results predicted by the proposed model were compared with analysis results of Life-365, a computer program for predicting the service life of reinforced concrete structures exposed to chlorides. In conclusion, the proposed model would be promising to predict the chloride ion profile and to estimate the service life of RC structures.

The Study on the Ion Water Characteristics of Raw Water in the Domestic Natural Mineral Water (국내 유통 중인 먹는샘물 원수의 이온류 수질 특성에 관한 연구)

  • Lee, Leenae;Ahn, Kyunghee;Min, Byungdae;Yang, Mihee;Choi, Incheol;Chung, Hyenmi;Park, Juhyun
    • Journal of Korean Society on Water Environment
    • /
    • v.32 no.5
    • /
    • pp.442-449
    • /
    • 2016
  • The goal of this study is to provide basic data to establish a foundation for the provision of safe drinkable water. The raw water of natural mineral water was analyzed to determine the quantities of anions (F-, Cl-, NO3-N-, and SO42- ) and cations (Ca2+, K+, Mg2+, and Na+) during the former and latter half of 2016. Analysis of the current quality of the raw water of natural mineral water among domestic manufacturers showed average anions contents of 0.46mg/L of fluorine, 8mg/L of chlorine ion, 1.5mg/L of nitrate nitrogen, and 12mg/L of sulfate ion. While the fluorine content was greater than the water quality criterion of 2.0mg/L at four points, the fluorine level was overall stable. The average cations contents included 21.3mg/L of calcium, 1.0mg/L of potassium, 3.4mg/L of magnesium, and 9.6mg/L of sodium. The chemical characteristics were compared among the major ions, and the results are presented in a piper diagram. The content ratio of cations was in the order of Ca2+> Na+>Mg2+>K+, whereas that of anions was in the order of SO42->Cl->NO3-N->F-. While the cations were slightly scattered, the anions were generally concentrated except for at a few points. The Ca-Na-HCO3 type was dominant overall in water sources from diorite, gneiss, and granite, while the Na-Mg-Ca-HCO3-Cl type was dominant in basalt sources. Mineral water manufacturers source their water under various conditions, including in-hole casing, excavation depth, and contact state of bedrock; even within the same rocky area, some differences in the water quality type can occur. When the depth of the water source was taken into account, the mean anions contents of F-, Cl-, NO3-N-, and SO42- were similar, with no significant differences according to depth. Of the cations, K+ and Na+ showed no significant differences across all the tubular wells, whereas Ca2+ and Mg2+ decreased in content with depth.

A Study on the Stabilization of the Papain Enzyme in the Moderately Concentrated Anionic Surfactant System (음이온 계면활성제에서 파파인 효소의 안정도에 관한 연구)

  • Kim, Ji-Yeong;Kim, Jin-Woo;Kim, Yong-Jin;Lee, Jae-Wook;Lee, Hae-Kwang;Kang, Hak-Hee
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.33 no.2
    • /
    • pp.93-97
    • /
    • 2007
  • Even in the moderately concentrated anionic surfactant system, some special encapsulation method can shield the papain enzyme from proteolytic attacks. The stabilization of enzyme has been a major issue for successful therapies. In this study, we first stabilized an enzyme, papain in the microcapsules by using polyols, polyethyleneglycol (PEG), poly-propyleneglycol (PPG), and PEG-PPG-PEG block copolymer. In the analysis of EDS and CLSM, it was demonstrated that polyols are effectively located in the interface of papain and polymer. Polyols located in the interface had an ability to buffer the external triggers by hydrophobic partitioning, preventing consequently the catalytic activity of papain in the micro-capsules. Second. we introduced multi-layer capsulation methods containing ion complex. Such a moderately concentrated anionic surfactant system as wash-off cleansers, surfactants and waters can cause instability of entrapped enzymes. Surfactants and water in our final products swell the surface of enzyme capsules and penetrate into the core so easily that we can not achieve the effect of enzyme, papain. In this case, the ion complex multi-layer capsule composed of sodium lauroyl sarcosinate and polyquaternium-6 could effectively prevent water from penetration into the core enzyme, followed by in vivo test, and evaluate the stratum corneum (SC) turn-over speed.

Purification and Biological Activities of Bombesin Like Immunoreactivity from Skin of the Frog, Bombina orientalis in Korea (한국산 무당개구리 피부에 존재하는 Bombesin 유사면역 반응물질의 순수정제 및 생물학적 활성)

  • Kwon, Hyeok-Yil;Kim, Yil;Park, Hyoung-Jin
    • The Korean Journal of Physiology
    • /
    • v.24 no.2
    • /
    • pp.363-375
    • /
    • 1990
  • The present investigation was performed to purify bombesin-like immunoreactivity (BBS-LI) from the skin of frogs, B. orientalis inhabiting Korea. For extraction of BBS-LI, the fresh skin of 360 g from frogs was immersed in 1,800 ml of 100% methanol and then kept at $4^{\circ}C$ for 5 days. BBS-LI was partially purified by liquid chromatography using an alkaline alumina column followed by a Sephadex G-10 column. BBS-LI was further purified by using sequential HPLC of reversed phase C18 preparation, gel permeation, SP-ion exchange and reversed phase C18 analysis. BBS-LI in fractions of each step was monitored by radioimmunoassay for which bombesin antiserum with a titer of 1 : 188,800 was raised in a guinea pig. Eventually, two different BBS-LI were successfully purified and each BBS-LI showed the following character. 1) BBS-LI was well separated into two peaks in SP-ion exchange HPLC. One (BBS-LI-K1) bound to the column while the other (BBS-LI-K2) did not. 2) BBS-LI-K1, 73.8% of total BBS-LI, was not differentiated from synthetic bombesin in reversed phase C18 analytical and gel permeation HPLC. 3) BBS-LI-K2, 26.2% of total BBS-LI, eluted later than synthetic bombesin in reversed phase C18 analytical HPLC, but it eluted with a retention time identical to that of synthetic bombesin in gel permeation HPLC. 4) The two forms of BBS-LI and synthetic bombesin identically stimulated gastrin release and pancreatic exocrine secretion including volume, protein output and amylase output in anesthetized rats. It is concluded from the above results that the skin of B. orientalis contains two different forms of BBS-LI which are very identical to bombesin immunologically and biologically. In comparison with synthetic bombesin containing 14 amino acid residues, the major form shows quite similar pattern in all HPLC used in the present study, but the minor form exhibits quite different pattern in SP-ion exchange and reversed phase C18 analytical HPLG.

  • PDF

Comparison of the Number Concentration and the Chemical Composition of the Atmospheric PM2.5 in Jeju Area

  • Kang, Chang-Hee;Hu, Chul-Goo
    • Journal of Environmental Science International
    • /
    • v.23 no.5
    • /
    • pp.743-753
    • /
    • 2014
  • The number concentrations and the water soluble ionic concentrations of $PM_{2.5}$ have measured at Gosan site in Jeju, Korea, from March 2010 to December 2010, to clarify their characteristics. $PM_{2.5}$ number concentrations vary from 22.57 to $975.65particles/cm^3$ with an average value of $240.41particles/cm^3$, which have been recorded evidently high in spring season as compared with those in other season. And the concentrations in small size ranges are greatly higher than those in large size ranges, so the number concentration in the size range $0.25{\sim}0.45{\mu}m$ has more than 94% of the total number concentration of $PM_{2.5}$. The major ionic components in $PM_{2.5}$ are $SO{_4}^{2-}$, $NH_4{^+}$ and $NO_3{^-}$, which are mainly originated from anthropogenic sources, on the other hand, the concentrations of $Cl^-$, $K^+$, $Ca^{2+}$ and $Mg^{2+}$ are recorded relatively lower levels. The concentrations of the major ionic components are very high in spring season, but the concentration levels of the other components are recorded significantly high in winter season. On the other hand, in summer season, the lowest concentration levels are observed for overall components as well as the sum of them. The concentration ratios of nss-$SO{_4}^{2-}/SO{_4}^{2-}$ and nss-$Ca^{2+}/Ca^{2+}$ are 98.1% and 88.9%. And the concentration ratio of $SO{_4}^{2-}/NO_3{^-}$(3.64) is greatly higher than the value in urban area due to no large $NO_x$ emission sources in the measurement. In addition, the correlation and the factor analysis for the number and the ionic concentrations of $PM_{2.5}$ are performed to identify their sources. From the Pearson correlation analysis and the factor analysis, it can be suggested that the smaller parts(< $0.5{\mu}m$) of $PM_{2.5}$ is contributed by anthropogenic sources, but the sources of the remaining larger parts of $PM_{2.5}$ are not able to be specified sources in this study.

Service Life Prediction of R.C. Structures Considering Chloride Binding (염화물 고정화를 고려한 철근 콘크리트 구조물의 내구수명 예측)

  • Lee, Chang-Soo;Park, Jong-Hyok;Kim, Young-Ook
    • Journal of the Korean Society of Hazard Mitigation
    • /
    • v.10 no.1
    • /
    • pp.15-22
    • /
    • 2010
  • Chloride-induced corrosion of steel bars in concrete exposed to marine environments has become one of the major causes of deterioration in many important facilities made of reinforced concrete. A study on chloride penetration in concrete has developed through long period exposure test along seawater, assesment of chloride ion diffusion by electrochemical techniques and so on. However, reasonable and exclusive chloride penetration model considering concrete material properties with mixture, degree of hydration, binding capacity has not been established. Therefore, in this paper, chloride penetration analysis of non-steady state is accomplished with material properties of concrete. Comparing with the results of analysis and chloride ponding test, we could accept the effect of binding capacity on chloride penetration in concrete and these results could be applied to a service life prediction of R.C. structures submerged in seawater. Therefore, there are 20~40% differences of service life to SHRP prediction.

Elemental Composition and Source Identification of PM2.5 in Jeju City (제주시 미세먼지(PM2.5)에 함유된 원소의 조성특성 및 오염원)

  • Lee, Ki-Ho;Hu, Chul-Goo
    • Journal of Environmental Science International
    • /
    • v.27 no.7
    • /
    • pp.543-554
    • /
    • 2018
  • From November 2013 to December 2016, ambient fine particulate matter ($PM_{2.5}$) was sampled in the downtown area of Jeju City, South Korea, which has seen rapid urbanization. The atmospheric concentrations of elements were measured in the $PM_{2.5}$ samples. This study focused on Cd, Cr, Cu, Mn, Ni, Pb, As, Sb, Sn, V, and Zn. The concentrations of Al, Na, K, Fe, Ca, Mg, Sr, and La were also obtained for reference. The objectives of this study were to examine the contributions of these elements to $PM_{2.5}$ concentrations in downtown Jeju City, and to investigate the inter-element relationships and the elemental sources by using enrichment factors and principal components analysis (PCA). A composition analysis showed that the 19 elements constituted 6.65 % of the $PM_{2.5}$ mass, and Na, K, Al, Fe, Ca, Mg, and Zn constituted 98 % of the total ion mass. Seasonal trend analysis for the sampling period indicated that the concentrations of the elements increased from November to April. However, no substantial seasonal variations were found in the concentrations of the elements. The composition ratios of some elements (Cu/Zn, Cu/Cd, Cu/Pb, V/Ni, and V/La) were found to be out of range when compared to the literature from other urban areas. The ratios between the elements and the PCA results showed that local contaminant sources in Jeju City rarely influence the composition of $PM_{2.5}$. This suggests that the major sources of $PM_{2.5}$ in Jeju City may include long-range transport of fine particulate matter produced in other areas.

Ecotoxicity Test of Wastewater by a Battery of Bioassay and Toxicity Identification Evaluation (다양한 시험생물종을 이용한 산업폐수 생태독성 평가 및 원인물질 탐색)

  • Ryu, Tae-Kwon;Cho, Jae-Gu;Kim, Kyung-Tae;Yang, Chang-Yong;Joung, Ki-Eun;Yoon, Jun-Heon;Choi, Kyung-Hee
    • Environmental Analysis Health and Toxicology
    • /
    • v.25 no.3
    • /
    • pp.207-214
    • /
    • 2010
  • Toxicity identification and quantification are important factors to evaluate the effect of industrial effluent on the aquatic environment. In order to measure the potential and real toxicity of mixed chemicals in the effluents, the biological method (i.e., WET test) should be used as well as chemical analysis method. In this study, we conducted WET test for various kinds of industrial effluents using aquatic organisms such as water flea (Daphnia magna), algae (Pseudokirchneriella subcapitata), fish (Oryzias latipes, Danio rerio), and microorganism (Vibrio fisheri). In addition, we carried out chemical analysis and TIE (Toxicity Identification Evaluation) for effluents in order to identify the substances causing toxicity. Among the 30 kinds of wastewater, S13 showed the highest eco-toxicity and $Ca^{2+}$ and $Cl^-$ ion were suspected as major compounds causing toxicity for aquatic organisms. In order to confirm these suspected compounds, various confirmation procedures need to be carried out.