Distribution of natural and anthropogenic radionuclides in northwest Mediterranean coastal sediments

Lee, Sang-Han,Povinec, Pavel P.,Chisholm, John R.M.,Levy, Isabelle,Miquel, Juan-Carlos,Oh, Jung-Suk Elsevier 2017 JOURNAL OF ENVIRONMENTAL RADIOACTIVITY Vol.172 No.-

<P><B>Abstract</B></P> <P>The distribution of radionuclides in NW Mediterranean coastal sediments, and the processes controlling their abundance were investigated in three cores taken near the island of Porquerolles and one offshore Monaco. The sediments collected near Porquerolles were strongly anoxic due to diagenetic processes involved in the decomposition of organic matter, whereas they transitioned from oxic to anoxic at a depth of 4 cm beneath the seawater interface at Monaco. Organic carbon (OC) was more abundant in sediments at Porquerolles (by about a factor of 3–5) than at Monaco and elsewhere in the coastal NW Mediterranean. Sediment cores collected NE of Porquerolles also possessed elevated uranium concentrations that correlated with high OC content and strong reducing conditions. The <SUP>239,240</SUP>Pu and <SUP>241</SUP>Am activities in surficial sediments ranged from 1 to 5.7 Bq kg<SUP>−1</SUP> and 0.3 to 1 Bq kg<SUP>−1</SUP>, respectively, while the <SUP>137</SUP>Cs activity ranged from 0.3 to 6.2 Bq kg<SUP>−1</SUP>. The mean activity ratios of <SUP>241</SUP>Am/<SUP>239,240</SUP>Pu and <SUP>238</SUP>Pu/<SUP>239,240</SUP>Pu in Porquerolles and Monaco sediments were similar to the global fallout ratios. Sediment inventories of global fallout <SUP>239,240</SUP>Pu (430–800 Bq m<SUP>−2</SUP>) and <SUP>241</SUP>Am (150–285 Bq m<SUP>−2</SUP>) were by about a factor of 5–10 higher at Porquerolles, whereas the inventory of <SUP>137</SUP>Cs (430–1000 Bq m<SUP>−2</SUP>) was substantially lower at the investigated stations than have been reported elsewhere at similar latitudes. Specific local conditions characterised by high OC sediment loads due to the growth and mortality of <I>Posidonia oceanica</I> have been responsible for deposition of large amounts of seagrass tissues at the NE corner of Porquerolles, which have had a profound effect on the distribution of radionuclides in the sediments.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Radionuclides in coastal sediments of NW Mediterranean were investigated. </LI> <LI> <SUP>241</SUP>Am/<SUP>239,240</SUP>Pu and <SUP>238</SUP>Pu/<SUP>239,240</SUP>Pu ratios consistent with global fallout ratios. </LI> <LI> <SUP>137</SUP>Cs mostly dissolved, but <SUP>239,240</SUP>Pu and <SUP>241</SUP>Am are particle reactive elements. </LI> <LI> Inventories of <SUP>239,240</SUP>Pu (430–800 Bq m<SUP>−2</SUP>) and <SUP>241</SUP>Am (150–285 Bq m<SUP>−2</SUP>) are high. </LI> <LI> Inventories of <SUP>137</SUP>Cs are significantly lower at all stations investigated. </LI> </UL> </P>

Characteristics of total gaseous mercury (TGM) concentrations in an industrial complex in South Korea: impacts from local sources

Seo, Yong-Seok,Jeong, Seung-Pyo,Holsen, Thomas M.,Han, Young-Ji,Choi, Eunhwa,Park, Eun Ha,Kim, Tae Young,Eum, Hee-Sang,Park, Dae Gun,Kim, Eunhye,Kim, Soontae,Kim, Jeong-Hun,Choi, Jaewon,Yi, Seung-Muk Copernicus GmbH 2016 Atmospheric Chemistry and Physics Vol.16 No.15

<P>Abstract. Total gaseous mercury (TGM) concentrations were measured every 5 min in Pohang, Gyeongsangbuk-do, Korea, during summer (17-23 August 2012), fall (9-17 October 2012), winter (22-29 January 2013), and spring (26 March-3 April 2013) to (1) characterize the hourly and seasonal variations of atmospheric TGM concentrations; (2) identify the relationships between TGM and co-pollutants; and (3) identify likely source directions and locations of TGM using the conditional probability function (CPF), conditional bivariate probability function (CBPF) and total potential source contribution function (TPSCF). The TGM concentration was statistically significantly highest in fall (6.7 ± 6.4 ng m−3), followed by spring (4.8 ± 4.0 ng m−3), winter (4.5 ± 3.2 ng m−3) and summer (3.8 ± 3.9 ng m−3). There was a weak but statistically significant negative correlation between the TGM concentration and ambient air temperature (r = −0.08, p<0.05). Although the daytime temperature (14.7 ± 10.0 °C) was statistically significantly higher than that in the nighttime (13.0 ± 9.8 °C) (p<0.05), the daytime TGM concentration (5.3 ± 4.7 ng m−3) was statistically significantly higher than that in the nighttime (4.7 ± 4.7 ng m−3) (p<0.01), possibly due to local emissions related to industrial activities and activation of local surface emission sources. The observed ΔTGM ∕ ΔCO was significantly lower than that of Asian long-range transport, but similar to that of local sources in Korea and in US industrial events, suggesting that local sources are more important than those of long-range transport. CPF, CBPF and TPSCF indicated that the main sources of TGM were iron and manufacturing facilities, the hazardous waste incinerators and the coastal areas. </P>

Progression of primary open angle glaucoma in asymmetrically myopic eyes

Song, M. K.,Sung, K. R.,Han, S.,Lee, J. E.,Yoon, J. Y.,Park, J. M.,Lee, J. Y. Springer Science + Business Media 2016 Graefe's archive for clinical and experimental oph Vol.254 No.7

<P>To compare progression of primary open angle glaucoma (POAG) in asymmetrically myopic eyes within the same subject and evaluate whether the degree of myopia is related to glaucoma progression. POAG patients with asymmetric myopia (axial length [AXL] a parts per thousand yen24 mm in both eyes, and the AXL difference between the right and left eyes to be a parts per thousand yen0.5 mm) were included. Glaucoma progression was determined either by optic disc/retinal nerve fiber layer (RNFL) photographs or by serial visual field (VF) data. The progression rates of VF mean deviation (dB/year) and spectral domain optical coherence tomography measured RNFL thickness (mu m/year) were compared between the more myopic eye (MME) and the less myopic eye (LME) within the same subject. A total of 55 patients (mean follow up period; 4.5 +/- 1.0 years) were included. The mean AXL demonstrated a significant difference between MME and LME (26.3 +/- 1.7 vs. 25.6 +/- 1.7 mm; p = 0.036). The mean baseline VF MD (-3.8 +/- 5.4 vs. -2.6 +/- 4.7 dB; p = 0.21) and average RNFL thickness (77.5 +/- 10.6 vs. 79.9 +/- 12.3 mu m; p = 0.36) did not differ between the MME and LME. Among the 55 patients, optic disc/RNFL photographic progression was noted in the MME in 15 patients, in the LME in 19 patients, and in both eyes in seven patients. VF progression was noted in the MME in seven patients, in the LME in seven patients, and in both eyes in four patients. The VF MD progression rates were -0.25 +/- 0.34 dB/year in MME and -0.26 +/- 0.34 dB/year in LME cases (p = 0.91). The mean progression rate of the average RNFL thickness also did not differ between the MME and LME (-0.59 +/- 0.67 vs. -0.66 +/- 0.72 mu m/year, p = 0.68). The degree of myopia was not associated with glaucoma progression when assessing the same patient using either the VF or optic disc/RNFL criteria in asymmetrically myopic patients.</P>

유착성 중이염 : 8증례에 대한 고찰

소진명,한장면,박성준 대한이비인후과학회 1970 대한이비인후과학회지 두경부외과학 Vol.13 No.4

폴리스티렌 표면상의 닉켈 화학도금에 관한 연구

조종수,한상목,최상흘 대한금속재료학회(대한금속학회) 1971 대한금속·재료학회지 Vol.9 No.3

폴리스티렌의 닉켈화학도금에서 전처리 및 도금시 용액조성과 조작상의 차가 있으나 활성화 처리를 하기 위한 염화파라디움 용액의 PH는 4.0∼4.5의 범위가 효과적이며 실온에서 약 1분간의 처리로 충분하였다. 도금액인 염화닉켈 용액에서 염화닉켈과 차아인산소다 및 초산소다의 조성비는 3 : 1 : 1이면 효과적이고 PH는 4부근, 온도는 90℃ 이상이면 좋겠다. At the pretreatment of base surface and chemical plating of nickel on the surface of polystyrene there are various differency by solution composition and processing. However, the best range of PH in palladium chloride solution for sensitizing was 4.0∼4.5, and the treatment was completed with one minute at the room temperature. The effective composition ratio of solution was 3:1:1 of nickel chloride, sodium hypophosphite and sodium acetate respectively, its PH was 4, and adequate temperature was over 90℃.

화학도금으로 얻은 유리-닉켈 계면에 관한 연구

조종수,한상목,최상흘 대한금속재료학회(대한금속학회) 1971 대한금속·재료학회지 Vol.9 No.2

비금속 소지인 소다 유리면에 닉켈을 무전해 도금하여 유리와 닉켈간의 계면을 조사하였다. 도금된 시편의 계면은 반사현미경과 전자현미경으로 관찰하였으며, 열처리 된 시편은 X-선 회절로 구조상의 변화 여부를 조사하였다. 소지면과 금속 도금층 간의 접착 기구는 현미경 관찰에 의하면, 주로 기계적인 현상으로 볼 수 있으며 도브테일(dove-tail)과 같은 결합에 의하여 접착은 강화되고 그 밖에도 중간 층에 의한 가능성도 무시할 수 없는 것 같다. Sodium glass was used as non-metallic base for electroless nickel deposits for the study of interfacial phenomena between glass and nickel. After nickel deposition, the interface of specimen was observed by reflection microscope and electron microscope. The structural change of heat treated specimen was studied by X-ray diffraction method. The adhesion mechanism of metallic layer and base surface might be mainly mechanical phenomena according to the observation from electron micrographs. Strong adhesion was produced by the formation of numerous joints as dove-tails. Furthermore, possible intermediate phase could be presumably proposed as an important role of the adhesion between the two phases.

The Effects of Cavity Size and Denticity of Thia-14-Crown-4 Ether Derivatives: Synthesis, DFT Studies, and its Application for the Separation of Pd and Pt from Spent Auto-catalyst Leachate

( Rey Eliseo C. Torrejos ),( Grace M. Nisola ),( Sang Hoon Min ),( Jeong Woo Han ),( Khino J. Parohinog ),( Seongpoong Lee ),( Wook-jin Chung ) 한국폐기물자원순환학회(구 한국폐기물학회) 2019 ISSE 초록집 Vol.2019 No.-

Dihydroxy-dithia-, -trithia-, and -tetrathia-14-crown-4 ether derivatives (2g-2m) were effectively synthesized by bis-epoxide ring-opening cyclization reaction with 1,2-benzenedithiol using a mild base triethylamine and LiCl as template in water. Experimental liquid-liquid extraction (LLE) and density functional theory (DFT) calculations reveal that the cavity size and denticity of the synthesized thiacrown ethers (CEs) affected their selectivity towards palladium (Pd) and platinum (Pt). Among the CE derivatives, bidentate dihydroxy-dibenzo-dioxadithia-14-crown ether (2i) with a calculated cavity size of 1.58-1.65 Ǻ was most selective towards Pd (1.56 Ǻ) whereas tetradentate dihydroxy-benzo-dimethyl-tetrathia-14-crown-4 ether (2m) with a cavity size of 1.31-1.60 Ǻ towards Pt (1.48 Ǻ), due to the CE cavity size-match relationship. The metals, Mⁿ⁺ (Pd or Pt) are situated perfectly inside the CE cavity with an S4 CE-Mⁿ⁺complex coordination geometry and the lowest DFT calculated binding energies (ΔE_CE-M ⁿ⁺).The dihydroxy thiacrown ethers can be further modified by alkylation for LLE application or polymerized via epoxy functionalization for solid-liquid extraction application of Pd or Pt from highly acidic auto-catalyst leachate. LLE performance of 2i in toluene-water system showed 99.99% Pd extraction efficiency with selectivity up to 10⁵ in comparison to other competing metals from highly acidic auto-catalyst leachate. Epoxy-polymerization of epoxide functionalized CEs with diamine as curing agent to afford highly selective adsorbents for Pd or Pt separation were also investigated and showed excellent Pd and Pt separation performance. This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No. 2017R1D1A1B03028102).

Ku band용 초전도 마이크로스트립 안테나의 제작 및 특성 해석

정동철,이중근,김민기,박성진,황종선,한병성 전북대학교 공업기술연구소 1998 工學硏究 Vol.30 No.-

In this paper, a comparative study between superconducting microstrip antennas and gold antennas is reported in terms of the return loss, the characteristic impedance, efficiency and other various characteristics. HTS thin films used in this work were fabricated on YBa_2Cu_3O_7-x(YBCO)/MgO substrate. Superconducting microstrip antennas used in this work is that the feed line was directly inset a microstrip transmission line into 50 Ω region of the radiating patch. Measurements from HTS antennas and gold antennas showed that usable antennas could be made by using this architecture.

원발성 간암에서 PIVKA-II 및 Lens Culinaris Agglutinin-A 반응성 Alpha-fetoprotein(AFP-L3)의 임상적 유용성

배시현,박두호,양진모,박영민,차상복,최종영,성광용,조세현,정규원,선희식,김부성,최상욱,변병훈,한남익 대한간학회 2000 Clinical and Molecular Hepatology(대한간학회지) Vol.6 No.2

Background/Aims: Des-γ-carboxy prothrombin(DCP), a protein induced by vitamin K absence or antagonist-II(PIVKA-II), and Lens culinaris agglutinin-A reactive AFP-L3 have been reported to be useful markers for the diagnosis of hepatocellular carcinoma (HCC). In the present study, both the PIVKA-II and AFP-L3 were analyzed and compared with a conventional AFP to determine its usefulness, specificity and sensitivity in the diagnosis of HCC. Methods: Sera were collected from 108 patients consisting of 17 patients with chronic hepatitis, 22 patients with liver cirrhosis and 69 patients with HCC. The AFP-L3 was determined by an lectin affinity electrophoresis coupled with an antibody-affinity blotting. Level of DCP was measured by an enzyme immunoassay with an anti-DCP monoclonal antibody. Results: The sensitivity and specificity of PIVKA-II and AFP L3 were 49.3% and 89.5%, and 32.5% and 85.7%, respectively. No significant correlation was found between the PIVKA-II or AFP L3 and serum AFP. No correlation was found etween the PIVKA-II or AFP L3 and the characteristics of HCC. Conclusion: The determination of plasma DCP and AFP L3 levels combined with AFP levels may be useful especially for the differential diagnosis between HCC and chronic liver diseases without HCC.(Korean J HepatoBackground/Aims: Des-γ-carboxy prothrombin(DCP), a protein induced by vitamin K absence or antagonist-II(PIVKA-II), and Lens culinaris agglutinin-A reactive AFP-L3 have been reported to be useful markers for the diagnosis of hepatocellular carcinoma (HCC). In the present study, both the PIVKA-II and AFP-L3 were analyzed and compared with a conventional AFP to determine its usefulness, specificity and sensitivity in the diagnosis of HCC. Methods: Sera were collected from 108 patients consisting of 17 patients with chronic hepatitis, 22 patients with liver cirrhosis and 69 patients with HCC. The AFP-L3 was determined by an lectin affinity electrophoresis coupled with an antibody-affinity blotting. Level of DCP was measured by an enzyme immunoassay with an anti-DCP monoclonal antibody. Results: The sensitivity and specificity of PIVKA-II and AFP-L3 were 49.3% and 89.5%, and 32.5% and 85.7%, respectively. No significant correlation was found between the PIVKA-II or AFP-L3 and serum AFP. No correlation was found etween the PIVKA-II or AFP L3 and the characteristics of HCC. Conclusion: The determination of plasma DCP and AFP-L3 levels combined with AFP levels may be useful especially for the differential diagnosis between HCC and chronic liver diseases without HCC.(Korean J Hepatol 2000;6:205-214)l 2000;6:205-214)

Synthesis and characterization of novel astragalin galactosides using β-galactosidase from <i>Bacillus circulans</i>

Han, Songhee,Hanh Nguyen, Thi Thanh,Hur, Jaewon,Kim, Nahyun M.,Kim, Seong-Bo,Hwang, Kyeong-Hwan,Moon, Young-Hwan,Kang, Choongil,Chung, Byoungsang,Kim, Young-Min,Kim, Tae Sung,Park, Jun-Seong,Kim, Doma Elsevier 2017 Enzyme and microbial technology Vol.103 No.-

<P>Astragalin (kaempferol-3-O-beta-D-glucopyranoside, Ast) is a kind of flavonoid known to have anti-oxidant, anti-HIV, anti-allergic, and anti-inflammatory effects. It has low solubility in water. In this study, novel astragalin galactosides (Ast-Gals) were synthesized using beta-galactosidase from Bacillus circulans and reaction conditions were optimized to increase the conversion yield of astragallin. Purified Ast-Gal1 (11.6% of Ast used, w/w) and Ast-Gal2 (6.7% of Ast used, w/w) were obtained by medium pressure chromatography (MPLC) with silica C-18 column and open column packed with Sephadex LH-20. The structures of Ast-Gal1 and Ast-Gal2 were identified by nuclear magnetic resonance (NMR) to be kaempferol-3-O-beta-D-glucopyranosyl-(1 -> 6)-beta-D-galactopyranoside and kaempferol-3-O-beta-D-glucopyranosyl-(1 -> 6)-beta-D-galactopyranosyl-(1 -> 4)-beta-D-galactopyranoside, respectively. The water solubility of Ast, Ast-Gal1, and Ast-Gal2 were 28.2 +/- 1.2 mg/L, 38,300 +/- 3.5 mg/L, and 38,800 +/- 2.8 mg/L, respectively. The SC50 value (the concentration required to scavenge 50% of the ABTS.+) of Ast, Ast-Gal1, and Ast-Gal2 were 5.1 +/- 1.6 mu M, 6.5 +/- 0.4 mu M, and 4.9 +/- 1.1 mu M, respectively. The IC50 values (the half maximal inhibitory concentration) of Ast, Ast-Gal1, and Ast-Gal2 against angiotensin converting enzyme (ACE) were 171.0 +/- 1.2 mu M, 186.0 mu M, and 139.0 +/- 0.2 mu M, respectively.</P>