RESUMO
In the process of studying the diversity of Xylariales in China, three species owning characteristics of Graphostromataceae were observed in China. Morphology of the described species with illustrations and their phylogeny based on regions of internal transcribed spacers (ITS), the second-largest subunit of the RNA polymerase II (RPB2), ß-tubulin (TUB2) and α-actin (ACT) are provided. Two new species and one new record from China are identified. Morphologically, Biscogniauxia glaucae sp. nov. differs from B. atropunctata var. maritima, B. citriformis var. macrospora, B. fuscella and B. mediterranea by its stromata with raised margins, clear outlines, punctate ostioles openings and ascospores which are equilateral with broadly rounded ends, a straight spore-length germ slit on the more concave side, lacking appendages and sheathes. Graphostroma guizhouensis is identified as a new species based on the multi-gene phylogenetic tree. Camillea broomeana with scanning electron microscope description of ascospores is illustrated as a new record from China. Cryptostroma is proposed in Graphostromataceae based on molecular data. Vivantia is accepted in Graphostromataceae based on its morphological characteristics and Nodulisporiurn anamorphs which are similar to those of Biscogniauxia.
Assuntos
Xylariales , China , DNA Fúngico/genética , DNA Ribossômico , Filogenia , Análise de Sequência de DNA , Xylariales/genéticaRESUMO
The detection of α particles is of great significance in military and civil nuclear facility management. At present, the contact method is mainly used to detect α particles, but its shortcomings limit the broad application of this method. In recent years, preliminary research on noncontact α-particle detection methods has been carried out. In this paper, the theory of noncontact α-particles detection methods is introduced and studied. We also review the direct detection and imaging methods of α particles based on the different wavelengths of fluorescence photons, and analyze the application and development of this method, providing an important reference for researchers to carry out related work.
Assuntos
Partículas alfaRESUMO
[This corrects the article DOI: 10.3897/mycokeys.100.109423.].
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An effective standoff alpha radiation measurement of surface contamination method is of great importance in radioactive waste disposal and decommissioning of nuclear facilities, nuclear accident emergency response and nuclear security. Here, we build an optical system for the implementation of standoff alpha radiation measurement based on radioluminescence. We present the results of the detection efficiency calibrating of standoff alpha radioactive sources using simulation and experiment. At the same time, a numerical integration-based surface contamination measurement method is designed, computed, and validated through experiments and simulations. Finally, the minimum detectable surface activity of the method is given for different measurement conditions.
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Pleosporales comprise a diverse group of fungi with a global distribution and significant ecological importance. A survey on Pleosporales (in Didymosphaeriaceae, Roussoellaceae and Nigrogranaceae) in Guizhou Province, China, was conducted. Specimens were identified, based on morphological characteristics and phylogenetic analyses using a dataset composed of ITS, LSU, SSU, tef1 and rpb2 loci. Maximum Likelihood (ML) and Bayesian analyses were performed. As a result, three new species (Neokalmusiakarka, Nigrogranaschinifolium and N.trachycarpus) have been discovered, along with two new records for China (Roussoellaneopustulans and R.doimaesalongensis) and a known species (Roussoellapseudohysterioides). Morphologically similar species and phylogenetically close taxa are compared and discussed. This study provides detailed information and descriptions of all newly-identified taxa.
RESUMO
During an investigation of Diatrypaceae from southern China, 10 xylariales-like taxa have been collected. Morphological and multi-gene analyses confirmed that these taxa reside in Diatrypaceae and represent eight novel taxa and two new records belonging to six genera (viz., Allocryptovalsa, Diatrype, Diatrypella, Paraeutypella, Peroneutypa, and Vasilyeva gen. nov.). Vasilyeva gen. nov. was proposed to accommodate Vasilyeva cinnamomi sp. nov. Among the other collections, seven new species were introduced (viz., Diatrype camelliae-japonicae sp. nov., Diatrype rubi sp. nov., Diatrypella guiyangensis sp. nov., Diatrypella fatsiae-japonicae sp. nov., Paraeutypella subguizhouensis sp. nov., Peroneutypa hainanensis sp. nov., and Peroneutypa qianensis sp. nov.), while two were reported as new records from China (Allocryptovalsa rabenhorstii and Diatrype enteroxantha). For Diatrypaceae, the traditional taxonomic approach based on morphology may not be applicable.
RESUMO
The chemical corrosion aging of plutonium is a very important topic. It is easy to be corroded and produces oxidation products of various valence states because of its 5f electron orbit between local and non-local. On the one hand, the phase diagram of plutonium and oxygen is complex, so there is still not enough research on typical structural phases. On the other hand, most of the studies on plutonium oxide focus on PuO2 and Pu2O3 with stoichiometric ratio, while the understanding of non-stoichiometric ratio, especially for Pu2O3-x, is not deep enough. Based on this, using the DFT + U theoretical scheme of density functional theory, we have systematically studied the structural stability, lattice parameters, electronic structure, mechanical and optical properties of six typical high temperature phases of ß-Pu2O3, α-Pu2O3,γ-Pu2O3, PuO, α-PuO2,γ-PuO2. Further, the mechanical properties and optical behavior of Pu2O3-x under different oxygen vacancy concentrations are analyzed and discussed in detail. The result shows that the elasticity modulus of single crystal in mechanical properties is directly related to the oxygen/plutonium ratio and crystal system. As the number of oxygen vacancies increases, the mechanical constants continue to increase. In terms of optical properties, PuO has the best optical properties, and the light absorption rate decreases with the increase of oxygen vacancy concentration.
RESUMO
In this study, fungal specimens of the family Diatrypaceae were collected from karst areas in Guizhou, Hainan and Yunnan Provinces, China. Morpho-molecular analyses confirmed that these new collections comprise a new genus Pseudodiatrype, three new species (Diatrypelancangensis, Diatrypellapseudooregonensis and Eutypacerasi), a new combination (Diatrypellaoregonensis), two new records (Allodiatrypethailandica and Diatrypellavulgaris) from China and two other known species (Neoeutypellabaoshanensis and Paraeutypellacitricola). The new taxa are introduced, based on multi-gene phylogenetic analyses (ITS, ß-tubulin), as well as morphological analyses. The new genus Pseudodiatrype is characterised by its wart-like stromata with 5-20 ascomata immersed in one stroma and the endostroma composed of thin black outer and inner layers of large white cells with thin, powdery, yellowish cells. These characteristics separate this genus from two similar genera Allodiatrype and Diatrype. Based on morphological as well as phylogenetic analyses, Diatrypelancangensis is introduced as a new species of Diatrype. The stromata of Diatrypelancangensis are similar to those of D.subundulata and D.undulate, but the ascospores are larger. Based on phylogenetic analyses, Diatrypeoregonensis is transferred to the genus Diatrypella as Diatrypellaoregonensis while Diatrypellapseudooregonensis is introduced as a new species of Diatrypella with 8 spores in an ascus. In addition, multi-gene phylogenetic analyses show that Eutypacerasi is closely related to E.lata, but the ascomata and asci of Eutypacerasi are smaller. The polyphyletic nature of some genera of Diatrypaceae has led to confusion in the classification of the family, thus we discuss whether the number of ascospores per asci can still be used as a basis for classification.