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Abstract  

Monochromatic MeV-energy neutron source for secondary reaction was developed utilizing tritium embedded titanium (Ti-3H) thin film via 3H(p,n)3He reaction. We have measured the neutron energies and the energy spread by resonance reactions of 12C(n,tot) and 28Si(n,tot). The available energy was within the range from 0.6 to 2.6 MeV. Energy spread was 1.6% at energy of 2.077 MeV. The flux in the beam direction was determined to be 3.76·107 n/s/sr by irradiating 197Au by about 2 MeV neutrons. This source was shown to be useful for measurements of nuclear data by measuring the total cross sections of neutrons on Fe and comparing these data to the data of ENDF-6.

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Abstract  

Trace impurity elements in high purity copper metal (4 mine class) put on the market were analyzed by Instrumental Neutron Activation Analysis (INAA) and the results compared with those from Graphite Furnace Atomic Absorption Spectrophotometry (GFAAS) and Inductively Coupled Plasma Atomic Emission Spectrophotometry (ICP-AES). The sample irradiation was done at the irradiation facilities (thermal neutron flux, 5·1012 n·cm−2·s−1) of the TRIGA Mark-III research reactor in the Korea Atomic Energy Research Institute. Four unalloyed copper standards (NIST SRM # 393, 394, 395 and 398) were used to identify the accuracy and precision of the analytical procedure. The homogeneity of samples was assessed by means of the elements such as Ag, As, Co, Sb, Se and Zn. The analytical results of INAA, GFAAS and ICP-AES were in good agreement within expected uncertainties each other and showed the possibility of using them for the analytical quality control.

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Abstract  

A nanosecond proton bunching system has been constructed at Korea Institute of Geoscience and Mineral Resources (KIGAM). This pulsed ion beam will be converted into corresponding duration of neutron pulse, which can reduce the scattered neutron background during neutron spectroscopy. The pulsed beam is obtained by deflection and double bunching by RF field. RF fields are applied to deflection and bunching electrodes as 2 kV p-p, 4 MHz and 2 kV p-p, 8 MHz, respectively. A push-pull RF amplifier has been designed and constructed with a maximum output power of 300 W continuous wave (CW) between 2 and 30 MHz. The main parameters of bunching beam were as follows: 8 MHz repetition rate, 2 ns FWHM, approximately 20% of duty factor and the maximum energy spread of 2 keV within a pulse.

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Abstract  

Instrumental neutron activation analysis has been applied to semiconductor grade silicon to study the concentration levels of impurity elements, the contamination during the single crystal growing process, and the vertical and radial distributions of impurities, along with the decontamination effect in the analysis. Twenty elements of Au, Br, As, W, Cr, Co, Na, Eu, La, Se, Zn, U, Th, Hf, Fe, Sb, Ag, Ce, Tb and Ta have been analyzed in p- and n-type wafers, single crystals and a polycrystal by a single comparator method using two comparators of gold and cobalt. Considerable surface contamination has been found and could be removed by etching the surface with nitric and hydrofluoric acid before and after irradiation. The impurity concentration has been found to be generally increased in the process of single crystal growth. The vertical and radial distributions of impurities have revealed that some impurity elements were more concentrated in the top region of a single crystal rod than in the middle region, and that Br, Cr, La, Eu and Sb were enriched in the central region and As, U and Fe in the outer region.

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Abstract  

Interferences by uranium fission for95Zr,99Mo,103Ru,140La,141Ce and147Nd have been studied using a single comparator method with two monitors. The effect of the neutron energy spectrum on the interference factor was examined by using the effective activation cross section. All the activities of140La produced during neutron irradiation of uranium were included in the calculation of the factor for lanthanum. The calculated and experimental interference factors are in good agreement within 10% deviation. The results have been applied for the analysis of several rock samples containing uranium in a wide concentration range.

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Abstract  

Neutron capture cross sections on 63Cu and 186W were measured by fast neutron activation method at neutron energies from 1 to 2 MeV. Monoenergetic fast neutrons were produced by 3H(p,n)3He reaction. Neutron energy spread by target thickness, which was assumed to be the main factor of neutron energy spread, was estimated to be 1.5% at neutron energy of 2.077 MeV. Neutron capture cross sections on 63Cu and 186W were calculated by reference comparison method on those of 197Au(n,γ). Not only statistical errors of gamma-counts from samples but also systematic errors in the counting efficiency for HP Ge detector and the uncertainty of areal density of samples were considered in calculating neutron capture cross section. Estimated neutron capture cross sections on 63Cu and 186W were also compared with ENDF-6 data.

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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, J. P. Halda, E. Farkas, D. K. Upreti, A. Thell, J.-J. Woo, S.-O. Oh, and J.-S. Hur

Nineteen new to science species of lichen forming fungi, i.e.: Agonimia ascendens S. Y. Kondr., L. Lőkös et J.-S. Hur, A. sunchonensis S. Y. Kondr. et J.-S. Hur, A. yongsangensis S. Y. Kondr. et J.-S. Hur, Biatora loekoesiana S. Y. Kondr. et J.-S. Hur, Caloplaca ivanpisutii S. Y. Kond., L. Lőkös et J.-S. Hur, Candelariella makarevichiae S. Y. Kondr., L. Lőkös et J.-S. Hur, Huriella pohangensis S. Y. Kondr., L. Lőkös et J.-S. Hur, H. salyangiana S. Y. Kondr. et J.-S. Hur, Hyperphyscia oxneri S. Y. Kondr. et J.-S. Hur, Nectriopsis gangwondoensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Porina ulleungdoensis S. Y. Kondr., L. Lőkös, J. Halda et J.-S. Hur, Psoroglaena gangwondoensis S. Y. Kondr., L. Lőkös, J.-J. Woo et J.-S. Hur, Pyrenopsis cavernicola S. Y. Kondr., L. Lőkös et J.-S. Hur, Rhizocarpon sunchonense S. Y. Kondr. et J.-S. Hur, Rufoplaca ulleungensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Sarcogyne ulleungdoensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Skyttea bumyoungsungii S. Y. Kondr. et J.-S. Hur, Thelopsis gangwondoensis S. Y. Kondr., L. Lőkös, J.-J. Woo et J.-S. Hur, Topelia loekoesiana S. Y. Kondr., J.-J. Woo et J.-S. Hur, all from South Korea, as well as Gallowayella awasthiana S. Y. Kondr. et D. K. Upreti from India and Franwilsia skottsbergii S. Y. Kondr., A. Thell, S.-O. Oh et J.-S. Hur from Chile are described, illustrated and compared with closely related taxa. A key to Agonimia species known from Eastern Asia is also included.

Lecanora helicopis is recorded for Korea for the first time, as well as a number of new to Jeju-do Island species (i.e.: Agonimia loekoesii, Biatora pseudosambuci, Buellia extremoorientalis, and Ivanpisutia oxneri) are recorded. Additional data on conidiomata and morphological characters of thallus and apothecia and illustrations as well as data on newly located isotype specimens recently described from Canary Islands, Spain Fominiella tenerifensis are provided.

Two new combinations, i.e.: Phaeophyscia saxatilis (for Physcia saxatilis Kashiw.), and Xanthoparmelia umezuana (for Karoowia umezuana Moon K. H. et Kashiw.) are also proposed.

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Acta Botanica Hungarica
Authors: S. Y. Kondratyuk, D. K. Upreti, G. K. Mishra, S. Nayaka, K. K. Ingle, O. O. Orlov, A. S. Kondratiuk, L. Lőkös, E. Farkas, J.-J. Woo, and J.-S. Hur

Eight species, new for science, i.e.: Lobothallia gangwondoana S. Y. Kondr., J.-J. Woo et J.-S. Hur and Phyllopsora dodongensis S. Y. Kondr. et J.-S. Hur from South Korea, Eastern Asia, Ioplaca rinodinoides S. Y. Kondr., K. K. Ingle, D. K. Upreti et S. Nayaka, Letrouitia assamana S. Y. Kondr., G. K. Mishra et D. K. Upreti, and Rusavskia indochinensis S. Y. Kondr., D. K. Upreti et S. Nayaka from India and China, South Asia, Caloplaca orloviana S. Y. Kondr. and Rusavskia drevlyanica S. Y. Kondr. et O. O. Orlov from Ukraine, Eastern Europe, as well as Xanthoria ibizaensis S. Y. Kondr. et A. S. Kondr. from Ibiza Island, Spain, Mediterranean Europe, are described, illustrated and compared with closely related taxa.

Fominiella tenerifensis S. Y. Kondr., Kärnefelt, A. Thell et Feuerer is for the first time recorded from Mediterranean Europe, Huriella loekoesiana S. Y. Kondr. et Upreti is provided from Russia for the first time, and H. pohangensis S. Y. Kondr., L. Lőkös et J.-S. Hur for the first time from China, Phoma candelariellae Z. Kocakaya et Halıcı is new to Ukraine, and Staurothele frustulenta Vain. is recorded from the Forest Zone of Ukraine for the first time.

Twelve new combinations, i.e.: Bryostigma apotheciorum (for Sphaeria apotheciorum A. Massal.), Bryostigma biatoricola (for Arthonia biatoricola Ihlen et Owe-Larss.), Bryostigma dokdoense (for Arthonia dokdoensis S. Y. Kondr., L. Lőkös, B. G. Lee, J.-J. Woo et J.-S. Hur), Bryostigma epiphyscium (for Arthonia epiphyscia Nyl.), Bryostigma lobariellae (for Arthonia lobariellae Etayo), Bryostigma lapidicola (for Lecidea lapidicola Taylor), Bryostigma molendoi (for Tichothecium molendoi Heufl. ex Arnold), Bryostigma neglectulum (for Arthonia neglectula Nyl.), Bryostigma parietinarium (for Arthonia parietinaria Hafellner et Fleischhacker), Bryostigma peltigerinum (for Arthonia vagans var. peltigerina Almq.), Bryostigma phaeophysciae (for Arthonia phaeophysciae Grube et Matzer), Bryostigma stereocaulinum (for Arthonia nephromiaria var. stereocaulina Ohlert), are proposed based on results of combined phylogenetic analysis based on mtSSU and RPB2 gene sequences.

Thirty-one new combinations for members of the genus Polyozosia (i.e.: Polyozosia actophila (for Lecanora actophila Wedd.), Polyozosia agardhiana (for Lecanora agardhiana Ach.), Polyozosia altunica (for Myriolecis altunica R. Mamut et A. Abbas), Polyozosia antiqua (for Lecanora antiqua J. R. Laundon), Polyozosia bandolensis (for Lecanora bandolensis B. de Lesd.), Polyozosia behringii (for Lecanora behringii Nyl.), Polyozosia caesioalutacea (for Lecanora caesioalutacea H. Magn.), Polyozosia carlottiana (for Lecanora carlottiana C. J. Lewis et Śliwa), Polyozosia congesta (for Lecanora congesta Clauzade et Vězda), Polyozosia eurycarpa (for Lecanora eurycarpa Poelt, Leuckert et Cl. Roux), Polyozosia expectans (Lecanora expectans Darb.), Polyozosia flowersiana (Lecanora flowersiana H. Magn.), Polyozosia fugiens (for Lecanora fugiens Nyl.), Polyozosia invadens (for Lecanora invadens H. Magn.), Polyozosia juniperina (for Lecanora juniperina Śliwa), Polyozosia latzelii (for Lecanora latzelii Zahlbr.), Polyozosia liguriensis (for Lecanora liguriensis B. de Lesd.), Polyozosia massei (for Myriolecis massei M. Bertrand et J.-Y. Monnat), Polyozosia mons-nivis (for Lecanora mons-nivis Darb.), Polyozosia oyensis (for Lecanora oyensis M.-P. Bertrand et Cl. Roux), Polyozosia percrenata (for Lecanora percrenata H. Magn.), Polyozosia persimilis (for Lecanora hagenii subsp. persimilis Th. Fr.), Polyozosia poeltiana (for Lecanora poeltiana Clauzade et Cl. Roux), Polyozosia prominens (for Lecanora prominens Clauzade et Vězda), Polyozosia prophetae-eliae (for Lecanora prophetae-eliae Sipman), Polyozosia salina (for Lecanora salina H. Magn.), Polyozosia schofieldii (for Lecanora schofieldii Brodo), Polyozosia sverdrupiana (for Lecanora sverdrupiana Øvstedal), Polyozosia torrida (for Lecanora torrida Vain.), Polyozosia wetmorei (for Lecanora wetmorei Śliwa), Polyozosia zosterae (for Lecanora subfusca? zosterae Ach.)) are proposed.

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