55 research outputs found
SEM analysis of ion implanted SiC
SiC is a material used in two future energy production technologies, firstly as a photovoltaic layer to harness
the UV spectrum in high efficient power solar cells, and secondly as a diffusion barrier material for
radioactive fission products in the fuel elements of the next generation of nuclear power plants. For both
applications, there is an interest in the implantation of reactive and non-reactive ions into SiC and their
effects on the properties of the SiC. In this study 360 keV Ag+, I+ and Xe+ ions were separately implanted
into 6H–SiC and in polycrystalline SiC at various substrate temperatures. The implanted samples were
also annealed in vacuum at temperatures ranging from 900 C to 1600 C for various times. In recent
years, there had been significant advances in scanning electron microscopy (SEM) with the introduction
of an in-lens detector combined with field emission electron guns. This allows defects in solids, such as
radiation damage created by the implanted ions, to be detected with SEM. Cross-sectional SEM images of
6H–SiC wafers implanted with 360 keV Ag+ ions at room temperature and at 600 C and then vacuum
annealed at different temperatures revealed the implanted layers and their thicknesses. A similar result
is shown of 360 keV I+ ions implanted at 600 C into 6H–SiC and annealed at 1600 C. The 6H–SiC is not
amorphized but remained crystalline when implanting at 600 C. There are differences in the microstructure
of 6H–SiC implanted with silver at the two temperatures as well as with reactive iodine ions. Voids
(bubbles) are created in the implanted layers into which the precipitation of silver and iodine can occur
after annealing of the samples. The crystallinity of the substrate via implantation temperature caused differences
in the distribution and size of the voids. Implantation of xenon ions in polycrystalline SiC at
350 C does not amorphize the substrate as is the case with room temperature heavy ion bombardment.
Subsequent annealing of the implanted polycrystalline samples leads to increased thermal etching effects
such as grain boundary grooving. Damage due to channelling (or non-channelling) in the different crystallites
resulted also in differences in thermal etching in the crystallites.http://www.elsevier.com/locate/nimbhb201
NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics
Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset
Fungal Planet description sheets : 320–370
Novel species of fungi described in the present study include the following from Malaysia: Castanediella
eucalypti from Eucalyptus pellita, Codinaea acacia from Acacia mangium, Emarcea eucalyptigena from Eucalyptus
brassiana, Myrtapenidiella eucalyptorum from Eucalyptus pellita, Pilidiella eucalyptigena from Eucalyptus brassiana
and Strelitziana malaysiana from Acacia mangium. Furthermore, Stachybotrys sansevieriicola is described from
Sansevieria ehrenbergii (Tanzania), Phacidium grevilleae from Grevillea robusta (Uganda), Graphium jumulu from
Adansonia gregorii and Ophiostoma eucalyptigena from Eucalyptus marginata (Australia), Pleurophoma ossicola from
bone and Plectosphaerella populi from Populus nigra (Germany), Colletotrichum neosansevieriae from Sansevieria
trifasciata, Elsinoë othonnae from Othonna quinquedentata and Zeloasperisporium cliviae (Zeloasperisporiaceae
fam. nov.) from Clivia sp. (South Africa), Neodevriesia pakbiae, Phaeophleospora hymenocallidis and Phaeophleospora
hymenocallidicola on leaves of a fern (Thailand), Melanconium elaeidicola from Elaeis guineensis (Indonesia),
Hormonema viticola from Vitis vinifera (Canary Islands), Chlorophyllum pseudoglobossum from a grassland (India),
Triadelphia disseminata from an immunocompromised patient (Saudi Arabia), Colletotrichum abscissum from Citrus
(Brazil), Polyschema sclerotigenum and Phialemonium limoniforme from human patients (USA), Cadophora vitícola
from Vitis vinifera (Spain), Entoloma flavovelutinum and Bolbitius aurantiorugosus from soil (Vietnam), Rhizopogon
granuloflavus from soil (Cape Verde Islands), Tulasnella eremophila from Euphorbia officinarum subsp. echinus
(Morocco), Verrucostoma martinicensis from Danaea elliptica (French West Indies), Metschnikowia colchici from
Colchicum autumnale (Bulgaria), Thelebolus microcarpus from soil (Argentina) and Ceratocystis adelpha from
Theobroma cacao (Ecuador). Myrmecridium iridis (Myrmecridiales ord. nov., Myrmecridiaceae fam. nov.) is also
described from Iris sp. (The Netherlands). Novel genera include (Ascomycetes): Budhanggurabania from Cynodon
dactylon (Australia), Soloacrosporiella, Xenocamarosporium, Neostrelitziana and Castanediella from Acacia mangium
and Sabahriopsis from Eucalyptus brassiana (Malaysia), Readerielliopsis from basidiomata of Fuscoporia wahlbergii
(French Guyana), Neoplatysporoides from Aloe ferox (Tanzania), Wojnowiciella, Chrysofolia and Neoeriomycopsis
from Eucalyptus (Colombia), Neophaeomoniella from Eucalyptus globulus (USA), Pseudophaeomoniella from Olea
europaea (Italy), Paraphaeomoniella from Encephalartos altensteinii, Aequabiliella, Celerioriella and Minutiella from
Prunus (South Africa). Tephrocybella (Basidiomycetes) represents a novel genus from wood (Italy). Morphological
and culture characteristics along with ITS DNA barcodes are provided for all taxa.Alina V. Alexandrova was supported by the Russian Science
Foundation (project N 14-50-00029). Ekaterina F. Malysheva, Olga V.
Morozova,
Alexander E. Kovalenko and Eugene S. Popov acknowledge
financial support from the Russian Foundation for Basic Research (project
13-04-00838a and 15-04-04645a). Margarita Dueñas, María P. Martín and
M. Teresa Telleria acknowledge financial support from the Plan Nacional I+D+I
projects No. CGL2009-07231 and CGL2012-3559. Cony Decock gratefully acknowledges the financial support received from
the FNRS / FRFC (convention FRFC 2.4544.10), the CNRS-French Guiana
and the Nouragues staff, which enabled fieldwork in French Guiana, and the
Belgian State – Belgian Federal Science Policy through the BCCMTM research
programme.http://www.ingentaconnect.com/content/nhn/pimjam201
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