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Summary  

It is impossible to detect 14C and 3H by direct methods such as γ-spectroscopy because they are pure b-emitters and thus they are classified as hard to measure nuclides (HTM). In this paper the analysis results of 14C and 3H in the low level radioactive wastes (LLWs), including spent ion exchange resin, evaporated bottom and sludge are presented. The LLWs were generated by three nuclear power plants (NPPs), in Korea all with pressurized water type reactors (PWRs). A simultaneous separation procedure for 14C and 3H in LLWs was established by wet oxidation-acid stripping. A liquid scintillation analyzer was used for the measurement of 14C and 3H. It was found that the recovery of 14C and 3H was 82-99 and 78-103%, respectively, by wet oxidation-acid stripping with diluted standard solutions. At the lowest injection of 14C and 3H, i.e., at 1.44 Bq for 14C and 1.22 Bq for 3H, the minimum detectable activity (MDA) of 14C and 3H was calculated as 0.88 and 0.78 Bq/g, respectively, for the minimum allowable sample weight, using wet oxidation and 16 wt% H2SO4 acid. By the wet oxidation-16 wt% H2SO4 stripping method no interfering nuclides were detected in the trapping solution of 14CO2 and the distillate of 3H. The activity concentration range of 14C in the analyzed samples, i.e., spent ion exchange resin, evaporated bottom and sludge, was 0.17-110,000, 8.4-1380 and 0.1-10,006 Bq/g, respectively, and that of 3H in the same was from no detectable to 769, 134-14,383 and 0.7-4820 Bq/g, respectively.

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Summary  

The International Monitoring System is part of the global verification system of the Comprehensive Nuclear-Test-Ban Treaty and comprises an atmospheric radioactivity monitoring network of 80 particulate stations, 40 of which are to be equipped with noble-gas-detection capability. The network is supported by 16 radionuclide laboratories. The equipment has to be tailored to different environments and its reliability is proving to be an operational challenge.

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Abstract  

A radiochemical neutron activation analysis has been applied to 2N–4N grade titanium metal and its oxide. Twenty two impurities were separated in a group from scandium by a radiochemical separation method using cation exchange resin with HBr and HCl. The contents of the elements were calculated by a single comparator method using two monitors. The analytical results agree well within 10% deviation with those obtained by instrumental method. Eighteen elements, Na, Fe, Co, As, Se, Sr, Mo, Sb, La, Eu, Tb, Yb, Lu, Hf, Ta, W, Th and U, are determined in titanium oxides and 17 elements, Na, Cr, Fe, Co, Se, As, Zr, Mo, Sb, Cs, Ce, Tb, Yb, Hf, Ta, W and Th, in titanium metals.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: K. Kim, J. Bae, B. Park, D. Ahn, S. Paek, S. Kwon, J. Shim, S. Kim, H. Lee, E. Kim, and I. Hwang

Abstract  

A pyrochemical processing has become one of the potential technologies for a future nuclear fuel cycle. An integrated multi-physics simulation and electrotransport model of a molten-salt electrolytic process are proposed and discussed with respect to the recovery of pure uranium when using thermochemical data. This study has been performed to provide information for diffusion boundary layers between the molten salt (KCl-LiCl) and electrode. The diffusion-controlled electrochemical model demonstrate a prediction of the electrotransport behaviors of LWR spent fuel as a function of the time up to the corresponding electrotransport satisfying a given applied current based on a galvanostatic electrolysis.

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Acta Botanica Hungarica
Authors: S. Y. Kondratyuk, L. Lőkös, J. P. Halda, M. Haji Moniri, E. Farkas, J. S. Park, B. G. Lee, S.-O. Oh, and J.-S. Hur

Data on about 27 new for South Korea species of lichen-forming and lichenicolous fungi, including one new for science genus Verseghya and 11 new for science species, i.e.: Agominia loekoesii, Lecanora pseudosambuci, Nectriopsis verseghyklarae, Polysporina golubkovae, Protoparmeliopsis zerovii, Psoroglaena chirisanensis, Pyrenopsis chejudoensis, Ropalospora chirisanensis, Thelopsis chirisanensis, Trapelia coreana, and Verseghya klarae, as well as 27 taxa newly recorded for the country (Biatora aff. subduplex, Buellia cf. uberior, Caloplaca kedrovopadensis, Catillaria chalybaea, Coenogonium isidiatum, Dibaeis yurii, Halecania australis, H. lobulata, Intralichen christiansenii, Ivanpisutia oxneri, Lecania cf. olivacella, Lecanora lojkahugoi, L. sulphurea, Lecidella mandshurica, Lichenoconium erodens, Micarea lithinella, M. aff. stipitata, Muellerella pygmaea var. pygmaea, Oxneria alfredii, Pertusaria aff. flavocorallina, Phaeosporobolus alpinum, Polycoccum innatum, Porina fluminea, Rinodina xanthophaea, Ropalospora chloantha, Stigmidium cladoniicola, and S. epiramalina) are provided.

Additional localities for the recently reported or described 39 species from South Korea, and for 1 species (Oxnerella safavidiorum) from Iran and China (for the first time for China) are provided.

The following taxa newly recorded for South Korea, i.e. Ivanpisutia oxneri, Lecanora lojkahugoi, Lecidella mandshurica, Rinodina xanthophaea, Ropalospora chloantha, as well as the newly described Buellia chujadoensis and Verseghya klarae found to be rather common in this country.

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Thermodynamic transition properties of highly ordered smectic phases

Series of main-chain liquid crystalline polyethers

Journal of Thermal Analysis and Calorimetry
Authors: Y Yoon, R. -M. Ho, F. Li, B. Moon, D. Kim, J. -Y. Park, F. W. Harris, S. Z. D. Cheng, V. Percec, and P. Chu

A series of polyethers have been synthesized from 1-(4-hydroxy-4′-biphenyl)-2-(4-hydroxyphenyl)propane and α, Ω-dibromoalkanes having different numbers of methylene units [TPPs]. Both odd- and even-numbered TPPs [TPP(n=odd)s and TPP(n=even)s) exhibit multiple transitions during cooling and heating and they show little supercooling dependence, indicating close-to-equilibrium nature of these transitions. Combining the structural characterization obtainedvia wide angle X-ray diffraction powder and fiber patterns at different temperatures and the morphological observations from microscopy techniques, not only the nematic liquid crystalline phase but also highly ordered smecticF, smectic crystalG andH phases have been identified. The phase diagrams for both TPP(n=odd)s and TPP(n=even)s have been constructed [1–3]. Thermodynamic properties (enthalpy and entropy changes) during these transitions are studied based on differential scanning calorimetry experiments. The contributions of the mesogenic groups and methylene units to each ordering process can be separated and they indicate the characteristics of these processes thereby providing estimations of the transition types.

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Acta Botanica Hungarica
Authors: S. Y. Kondratyuk, L. Lőkös, J. P. Halda, D. K. Upreti, G. K. Mishra, M. Haji Moniri, E. Farkas, J. S. Park, B. G. Lee, D. Liu, J.-J. Woo, R. G. U. Jayalal, S.-O. Oh, and J.-S. Hur

Data on 54 new for China, India, Korea and Russia species of lichen-forming and lichenicolous fungi, including 22 new for science taxa of lichen-forming and lichenicolous fungi, i.e.: Acarospora ulleungdoensis, Amandinea trassii, Aspicilia geumodoensis, Biatora ivanpisutii, Caloplaca patwolseleyae, Catillaria ulleungdoensis, Coenogonium agonimieoides, Gyalidea austrocoreana, G. ropalosporoides, Opegrapha briancoppinsii, O. ulleungdoensis, Phyllopsora loekoesii, Psoroglaena coreana, Psorotichia gyelnikii, Rinodina oxneriana, Scoliciosporum jasonhurii, Staurothele oxneri, Stigmidium coarctatae, Thelocarpon ulleungdoense, Thelopsis loekoesii, Toninia poeltiana, Unguiculariopsis helmutii, and and 7 new species to China (Caloplaca ussuriensis, Megaspora rimisorediata, Rinodina xanthophaea, Rusavskia dasanensis, Xanthoria splendens, Zeroviella coreana, Z. esfahanensis), and 1 new species to India (Zeroviella esfahanensis), and 24 new species to Korea (Agonimia blumii, Arthonia rinodinicola, Buelliella minimula, Dactylospora australis, Endococcus propinguus, Halecania santessonii, Laeviomyces aff. fallaciosus, Lecanora albescens, L. layana, Lecidella scabra, Micarea farinosa, Minutoexcipula aff. mariana, Opegrapha anomaea, O. aff. xerica, Phoma aff. lecanorina, Polycoccum rubellianae, Porina nucula, Pyrenidium actinellum, Rhexophiale rhexoblephara, Rimularia badioatra, Rinodina confragosa, R. milvina, R. occulta, Tremella phaeophysciae), as well as 1 new species to Russia (Verseghya klarae) are provided. Furthermore new for science species of lichenicolous fungus Polycoccum clauderouxii from China is described. Four new combinations, i.e.: Biatora pseudosambuci (Basionym: Lecanora pseudosambuci S. Y. Kondr., L. Lőkös et J.-S. Hur), Buellia pseudosubnexa (Basionym: Hafellia pseudosubnexa S. Y. Kondr., L. Lőkös et J.-S. Hur), Buellia extremoorientalis (Basionym: Hafellia extremorientalis S. Y. Kondr., L. Lőkös et J.-S. Hur), and Sagedia nunatakkorum (Basionym: Lecanora nunatakkorum Poelt) are proposed. Data on conidiomata and conidia for lichenicolous fungus Opegrapha anomea Nyl are for the first time provided.

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Acta Botanica Hungarica
Authors: S. Y. Kondratyuk, L. Lőkös, J. P. Halda, C. Roux, D. K. Upreti, F. Schumm, G. K. Mishra, S. Nayaka, E. Farkas, J. S. Park, B. G. Lee, D. Liu, J.-J. Woo, and J.-S. Hur

Eighteen new to science species, i.e.: 13 taxa from South Korea (Astroplaca loekoesiana S. Y. Kondr., E. Farkas, J.-J. Woo et J.-S. Hur, Buellia ulleungdoensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Candelariella hakulinenii S. Y. Kondr., L. Lőkös et J.-S. Hur, Flavoplaca laszloana S. Y. Kondr. et J.-S. Hur, Lichenostigma epiporpidiae S. Y. Kondr., L. Lőkös et J.-S. Hur, Mikhtomia geumohdoensis S. Y. Kondr., Liu D. et J.-S. Hur, Orientophila dodongensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Physcia orientostellaris S. Y. Kondr., L. Lőkös et J.-S. Hur, Placynthiella hurii S. Y. Kondr. et L. Lőkös, Protoparmeliopsis kopachevskae S. Y. Kondr., L. Lőkös et J.-S. Hur, Psoroglaena sunchonensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Rufoplaca kaernefeltiana S. Y. Kondr., L. Lőkös et J.-S. Hur, Vezdaea poeltiana S. Y. Kondr., L. Lőkös, J. Halda et J.-S. Hur), two species from India (Rusavskia indica S. Y. Kondr. et D. K. Upreti, and R. upretii S. Y. Kondr., G. K. Mishra et S. Nayaka), and two species from Atlantic Europe, i.e.: Spain and Portugal (Xanthoria schummii S. Y. Kondr. and X. lapalmaensis F. Schumm et S. Y. Kondr.), as well as a lichenicolous fungus Leptosphaeria Oxneriae Cl. Roux et S. Y. Kondr. from Asia (Russia and India) are described, illustrated and compared with closely related taxa. Forty species of lichen forming and lichenicolous fungi (i.e.: Acarospora cf. rufescens, Agonimia allobata, A. aff. blumii, Anema decipiens, Anisomeridium aff. albisedum, Bacidia laurocerasi, Cercidospora aff. epipolytropa, C. aff. lobothallia, Dictyocatenulata alba, Fuscopannaria dissecta, Lecanora ussuriensis, Lecidella aff. carpatica, Lemmopsis arnoldiana, Leptosphaeria crozalsii, Lichenostigma cf. bolacinae, L. aff. rupicolae, Lichinella stipatula, L. cribellifera, L. iodopulchra, L. aff. myriospora, Melaspilea proximella, Micarea alabastrites, Opegrapha aff. thelotrematis, Orientophila leucerythrella, Pectenia plumbea, Placynthium tantaleum, Porpidia flavicunda, Psorula rufonigra, Pyrenocarpon aff. thelostomum, Pyrenodesmia duplicata, Pyrenopsis aff. haematina, Ramboldia haematites, Rhizoplaca subdiscrepans, Rimularia gibbosa, Rinodina oxydata, Staurothele frustulenta, Stigmidium cf. clauzadei, Strigula australiensis, Thelenella luridella, Vezdaea leprosa) are for the first time recorded for Korea. Additional locality records for South Korea (74 species) and China (3 species) are also given.

Four new combinations, i.e.: Orientophila chejuensis (for Caloplaca chejuensis S. Y. Kondr. et Hur), Orientophila diffluens (for Lecanora diffluens Hue), Orientophila leucerythrella (for Lecanora leucerythrella Nyl.), and Pyrenodesmia duplicata (for Lecanora duplicata Vain.) are also proposed.

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Acta Botanica Hungarica
Authors: S. Y. Kondratyuk, L. Lőkös, D. K. Upreti, S. Nayaka, G. K. Mishra, S. Ravera, M.-H. Jeong, S.-H. Jang, J. S. Park, and J.-S. Hur

Seventeen robust monophyletic branches newly discovered in the phylogenetic tree of the Teloschistaceae after separate nrITS, nrLSU and mtSSU, as well as combined phylogenetic analysis are proposed to consider as the following separate genera: Dijigiella S. Y. Kondr. et L. Lőkös gen. nov. for the D. kaernefeltiana group, Elixjohnia S. Y. Kondr. et J.-S. Hur gen. nov. for the Sirenophila jackelixii group, Fominiella S. Y. Kondr., D. Upreti et J.-S. Hur gen. nov. for the F. tenerifensis group; Gintarasiella S. Y. Kondr. et J.-S. Hur gen. nov. for Caloplaca aggregata, Hanstrassia S. Y. Kondr. gen. nov. for the Elenkiniana lenae group, Harusavskia S. Y. Kondr. gen. nov. for H. elenkinianoides sp. n., Huriella S. Y. Kondr. et D. Upreti gen. nov. for H. loekoesiana sp. n., Ikaeria S. Y. Kondr., D. Upreti et J.-S. Hur gen. nov. for Caloplaca aurantiellina, Klauderuiella S. Y. Kondr. et J.-S. Hur gen. nov. for the Variospora thallincola group, Laundonia S. Y. Kondr., L. Lőkös et J.-S. Hur gen. nov. for the Gyalolechia flavovirescens group, Lazarenkoiopsis S. Y. Kondr., L. Lőkös et J.-S. Hur gen. nov. for Caloplaca ussuriensis, Nevilleiella S. Y. Kondr. et J.-S. Hur gen. nov. for the Caloplaca marchantii group, Opeltia S. Y. Kondr. et L. Lőkös gen. nov. for the Caloplaca neobaltistanica group, Oxneriopsis S. Y. Kondr., D. Upreti et J.-S. Hur gen. nov. for the Caloplaca oxneri group, Teuvoahtiana S. Y. Kondr. et J.-S. Hur gen. nov. for the Caloplaca rugulosa group, Tomnashia S. Y. Kondr. et J.-S. Hur gen. nov. for the Polycauliona rosei group, and Xanthaptychia S. Y. Kondr. et S. Ravera gen. nov. for the Seirophora orientalis group.

Hitherto missing molecular data on three gene sequences of the type species of the genera Seirophora and Sirenophila are completed within this study.

Six new to science species (Dijigiella kaernefeltiana S. Y. Kondr. sp. n., D. subaggregata S. Y. Kondr. et Kärnefelt sp. n., Fominiella tenerifensis S. Y. Kondr., Kärnefelt, A. Thell et T. Feuerer sp. n., Hanstrassia jaeseounhurii S. Y. Kondr., Ch.-H. Park et L. Lőkös sp. n., Harusavskia elenkinianoides S. Y. Kondr., X. Y. Wang, S.-O. Oh et J.-S. Hur sp. n., Huriella loekoesiana S. Y. Kondr. et D. Upreti sp. n.) are described, compared with closely related taxa.

A total of 34 new combinations for genera mentioned above are proposed.

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