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In this study, three Neopestalotiopsis taxa were identified, associated with leaves of Zingiber officinale, Elaeagnus pungens and Salacca zalacca.Based on morphology and multi–gene analyses of the internal transcribed spacer (ITS), beta-tubulin (TUB2) and translation elongation factor 1–alpha (TEF1), the five strains of Neopestalotiopsis represent two novel and one known species. They are introduced with descriptions, illustrations and notes herein.

Five ascomycetous strains were isolated from dead branches and leaves of Salix (Salicaceae) and Osmanthus fragrans (Oleaceae), respectively. BLAST searches with ITS sequences in GenBank suggested a high degree of similarity to Botryosphaeria dothidea. To accurately identify these strains, we further analysed their morphological characteristics of asci, ascospores, all conidiophore cells and conidia. Phylogenetic relationships, based on ITS, rpb2, tef1 and tub2 gene sequences, confirmed our strains represented two novel species, which are introduced here as B. salicicola and B. osmanthuse spp. nov. [ABSTRACT FROM AUTHOR]

Nidirana guangxiensis sp. nov., a new music frog species, is proposed, based on a series of specimens collected from Mt Daming, Guangxi, southern China. The new species is close to N. yeae, N. daunchina, N. yaoica, and N. chapaensis from southwestern and south-central China and northern Indochina, while the relationships among these species remain unresolved. Nidirana guangxiensis sp. nov. can be distinguished from all known congeners by the genetic divergences in the mitochondrial 16S and COI genes, the behavior of nest construction, the advertisement call containing 6-11 rapidly repeated regular notes, and a combination of morphological characteristics. Furthermore, the Nidirana populations recorded in Guangxi are clarified in this work, providing valuable new information on the knowledge of the genus Nidirana. [ABSTRACT FROM AUTHOR]

Background In the last few years, many microfungi--including plant-associated species--have been reported from various habitats and substrates in Italy. In this study of pleosporalean fungi, we researched terrestrial habitats in the Provinces of Arezzo (Tuscany region), Forlì-Cesena and Ravenna (Emilia-Romagna region) in Italy. New information Our research on Italian pleosporalean fungi resulted in the discovery of a new species, Italica heraclei (Phaeosphaeriaceae). In addition, we present a new host record for Pseudoophiobolus mathieui (Phaeosphaeriaceae) and the second Italian record of Phomatodes nebulosa (Didymellaceae). Species boundaries were defined, based on morphological study and multi-locus phylogenetic reconstructions using Maximum Likelihood and Bayesian Inference analyses. Our findings expand the knowledge on host and distribution ranges of pleosporalean fungi in Italy. [ABSTRACT FROM AUTHOR]

Two new toad species of the genus Leptobrachella are described from the Yunnan-Guizhou Plateau of China, based on the combination of molecular and morphological data. The description of Leptobrachella aspera Wang, Lyu, Qi & Wang, sp. nov. from Huanglianshan Nature Reserve represents the thirteenth Leptobrachella species known from Yunnan Province, and the description of Leptobrachella dorsospina Wang, Lyu, Qi & Wang, sp. nov. from Yushe Forest Park represents the sixth Leptobrachella species known from Guizhou Province. These new discoveries further emphasize the extremely high diversity of the Leptobrachella toads in these regions. [ABSTRACT FROM AUTHOR]

A definition of the Goniurosaurus yingdeensis group is presented in this study, on the basis of morphological and phylogenetic analyses based on a series of additional specimens. Moreover, a new species of this group, Goniurosaurus varius sp. nov., is proposed for northern Guangdong Province, China. The new species can be distinguished from the other two congeners of this group by the following unique characters: one or two internasals; enlarged supraorbital tubercles absent; paravertebral tubercles between limb insertions 27-29; dorsal tubercle rows at midbody 21-24; ten precloacal pores in males and absent in females; body bands with black spots; iris orange-red. [ABSTRACT FROM AUTHOR]

A new species of colubrid snake, Lycodon cathaya sp. nov., is described based on two adult male specimens collected from Huaping Nature Reserve, Guangxi, southern China. In a phylogenetic analyses, the new species is shown to be a sister taxon to the clade composed of L. futsingensis and L. namdongensis with low statistical support, and can be distinguished from all known congeners by the significant genetic divergence in the mitochondrial cytochrome b gene fragment (p-distance = 7.9%), and morphologically by the following combination of characters: (1) dorsal scales in 17-17-15 rows, smooth throughout; (2) supralabials eight, third to fifth in contact with eye, infralabials nine; (3) ventral scales 199-200 (plus two preventral scales), subcaudals 78; (4) loreal single, elongated, in contact with eye or not, not in contact with internasals; (5) a single preocular not in contact with frontal, supraocular in contact with prefrontal, two postoculars; (6) maxillary teeth 10 (4+2+2+2); (7) two anterior temporals, three posterior temporals; (8) precloacal plate entire; (9) ground color from head to tail brownish black, with 31-35 dusty rose bands on body trunk, 13- 16 on tail; (10) bands in 1-2 vertebral scales broad in minimum width; (11) bands separate ground color into brownish black ellipse patches arranged in a row along the top of body and tail; (12) elliptical patches in 3-6 scales of the vertebral row in maximum width; (13) ventral surface of body with wide brownish black strip, margined with a pair of continuous narrow greyish white ventrolateral lines. With the description of the new species, 64 congeners are currently known in the genus Lycodon, with 16 species occurring in China. [ABSTRACT FROM AUTHOR]

Recent phylogenetic analysis encompassing multilocus nuclear-gene and matrilineal mtDNA genealogy has revealed a series of cryptic species of the subgenus Panophrys within genus Megophrys from southern and eastern China. This study demonstrates that the Panophrys specimens from the hilly areas among Guangdong, Guangxi and Hunan can be morphologically distinguished from all recognized congeners, thereby providing additional supports for the recognitions of four new species of Panophrys, namely Megophrys (Panophrys) mirabilis Lyu, Wang & Zhao, sp. nov. from northeastern Guangxi, Megophrys (Panophrys) shimentaina Lyu, Liu & Wang, sp. nov. from northern Guangdong, and Megophrys (Panophrys) xiangnanensis Lyu, Zeng & Wang, sp. nov. and Megophrys (Panophrys) yangmingensis Lyu, Zeng & Wang, sp. nov. from southern Hunan. The descriptions of these species take the number of Megophrys species to 101, 46 of which belong to the subgenus Panophrys. [ABSTRACT FROM AUTHOR]

Rana jiulingensis sp. nov., a new species from Hunan and Jiangxi, southeastern China, is described. The new species is assigned to the R. japonica group. The clade comprising R. jiulingensis sp. nov. and R. dabieshanensis from Anhui is the sister taxon of R. omeimontis from Sichuan. Rana jiulingensis sp. nov. can be distinguished by the significant divergences in the 16S and COI genes, and the combination of following morphological characters: body size medium, SVL 48.3-57.8 mm in adult males and 48.2-57.5 mm in adult females; dorsolateral fold straight; digits without circummarginal grooves; dorsal skin smooth; tibiotarsal articulation reaching forward beyond the tip of snout; heels overlapping; webbing formula of toes: I 1 - 2 II 1 - 2 III 1½ - 2 IV 3 - 1 V; absence of vocal sacs in males; and presence of creamy white nuptial pad with tiny hoar spines on the finger I and reddish tubercles on loreal and temporal regions in breeding males. Furthermore, based on our results and the previous literature, R. zhengi is synonymized with R. sangzhiensis, and a new species group, the Rana johnsi group, is proposed for the R. johnsi and R. sangzhiensis. Currently, the subgenus Rana contains 41 recognized species, and the phylogenetic placements of several species remain unresolved. [ABSTRACT FROM AUTHOR]

Modified Davidson's fluid (mDF) is a good fixative for morphological and antigen preservation. However, recent studies have shown that 4% paraformaldehyde (PFA) can better preserve the actin structure in rodent testes. It remains controversial which of these fixatives is best for testicular tissue. This study investigated the effects of both mDF and 4% PFA on the morphology and antigen preservation of Xiang pig testes using hematoxylin-eosin (HE) staining and immunohistochemistry (IHC). The stronger testis penetration of mDF compared with that of 4% PFA was primarily manifested as testicular color change and decrease in tissue weight loss. Testes fixed with 4% PFA displayed a severe shrinkage of both the tubular and interstitial compartments and the seminiferous tubule area decreased by 12.02% compared with that in mDF-fixed tissues. In contrast, IHC results showed that 4% PFA fixation achieved better IHC-positive performance than mDF fixation for antigens specifically expressed in germ cells, Leydig cells and Sertoli cells. Due to this improved antigen preservation by 4% PFA fixation, the relative immunoreactions intensity significantly increased by 39.8%, 27.8%, and 76.4%, respectively, compared with that in mDF fixation. In summary, fixation of Xiang pig testes with mDF was suitable for HE staining, while fixation with 4% PFA was more suitable for IHC. [ABSTRACT FROM AUTHOR]

The genus-level recognition of monophyletic shortlegged toads (Brachytarsophrys) has been recently implicated in the taxonomic debate of Megophrys sensu lato. In the present study, Brachytarsophrys is reasonably regarded as a distinct genus based on significant morphological differentiations and recent molecular analyses. Furthermore, a comprehensive review of this genus is performed, with two species groups proposed based on morphological differences and phylogenetic relationships. Particularly, Brachytarsophrys platyparietus is removed as a synonym of Brachytarsophrys carinense and considered a valid species due to significant genetic divergence and distinct morphological differences. In addition, a new species, Brachytarsophrys orientalis sp. nov., is described based on a series of specimens collected from southeastern China. This work takes the member species of the genus Brachytarsophrys to seven, suggesting that the diversity of Brachytarsophrys is underestimated. In addition, the genus levels of other monophyletic groups within the subfamily Megophryinae are discussed. [ABSTRACT FROM AUTHOR]

Three cryptic species, which were previously reported as Nidirana adenopleura, are revealed on the basis of comprehensive approaches. Nidirana guangdongensis Lyu, Wan, and YY Wang, sp. nov. is distributed in Nanling Mountains and southern Luoxiao Mountains, Nidirana mangveni Lyu, Qi, and YY Wang, sp. nov. is known from northern Zhejiang, and Nidirana xiangica Lyu and YY Wang, sp. nov. occurs in Xiangjiang River Basin, while the true Nidirana adenopleura is designated from Taiwan Island, northern Fujian, southern Zhejiang, and central Jiangxi. These three new species can be distinguished from all congeners by significant divergences in the mitochondrial 16S and CO1 genes, differences in advertisement calls, and the combination of multiple characteristics. This work indicates that the current records of Nidirana adenopleura should be of a species complex composed of multiple species and have clarified the true identity of N. adenopleura. [ABSTRACT FROM AUTHOR]

A new species of Music frogs, Nidirana yaoica sp. nov. is described based on a series of adult male specimens collected from Mt Dayao, Guangxi, southern China, providing valuable new information on the phylogeny, bioacoustics, and biogeography of related species within the genus Nidirana. The new species forms the sister taxon to N. daunchina from western China and together the sister taxon to N. chapaensis from northern Vietnam. Nidirana yaoica sp. nov. can be distinguished from all known congeners by a significant genetic divergence in the mitochondrial 16S and CO1 genes, the advertisement call containing 1-3 rapidly repeated regular notes, and the combination of morphological characteristics including a medium-sized body with SVL 40.4-45.9 mm in adult males; lateroventral grooves on every digit, not meeting at the tip of disk; tibio-tarsal articulation reaching the nostril; the presence of a pair of subgular vocal sacs in males; and one single developed nuptial pad on dorsal surface of first finger in males. [ABSTRACT FROM AUTHOR]

Two new species of the genus Leptobrachella Smith, 1925, L. bijie J. Wang, Y.L. Li, Y. Li, H.H. Chen & Y.Y. Wang, sp. nov. and L. purpuraventra J. Wang, Y.L. Li, Y. Li, H.H. Chen & Y.Y. Wang, sp. nov., were described from northwestern Guizhou Province, China based on a combination of acoustic, molecular, and morphological data. The new discoveries bring the total number of this genus to 73, with 16 congeners recorded in China, and represent the second and third species of the genus reported from Guizhou Province. [ABSTRACT FROM AUTHOR]

The morphology, ecology, and phylogenetic relationships of specimens of the family Boletaceae from subtropical and tropical China were investigated. Four species, Butyriboletus huangnianlaii, Lanmaoa macrocarpa, Neoboletus multipunctatus, and Sutorius subrufus, are new to science. Chalciporus radiatus and Caloboletus xiangtoushanensis are redescribed. Caloboletus guanyui is proposed to replace Boletus quercinus Hongo, an illegitimate later homonym. The recently described Tylopilus callainus is synonymized with the Japanese Boletus virescens, and the new combination T. virescens (Har. Takah. & Taneyama) N.K. Zeng et al. is proposed. Moreover, Neoboletus is treated as an independent genus based on evidence from morphology and molecular phylogenetic data in the present study, and many previously described taxa of Sutorius are recombined into Neoboletus: N. ferrugineus (G. Wu et al.) N.K. Zeng et al., N. flavidus (G. Wu & Zhu L. Yang) N.K. Zeng et al., N. hainanensis (T.H. Li & M. Zang) N.K. Zeng et al., N. obscureumbrinus (Hongo) N.K. Zeng et al., N. rubriporus (G. Wu & Zhu L. Yang) N.K. Zeng et al., N. sanguineoides (G. Wu & Zhu L. Yang) N.K. Zeng et al., N. sanguineus (G. Wu & Zhu L. Yang) N.K. Zeng et al., and N. tomentulosus (M. Zang et al.) N.K. Zeng et al. [ABSTRACT FROM AUTHOR]

Two cryptic species, which were previously reported as Amolops ricketti, are revealed on the basis of significant morphological and genetic divergences. Amolops sinensis sp. n. from central Guangdong, northeastern Guangxi and southwestern Hunan can be distinguished by the longitudinal glandular folds on the skin of the shoulders and other character combinations. Amolops yatseni sp. n. from the coastal hills of west Guangdong can be distinguished by the dense tiny round translucent, or white, spines on the dorsal skin of the body, dorsal and dorsolateral skin of the limbs, and other character combinations. The phylogenetic interrelationships of the A. ricketti group have been inferred as (A. wuyiensis + A. ricketti) + (A. yunkaiensis + (A. albispinus + (A. sinensis sp. n. + A. yatseni sp. n.))). This work indicates that the current records of A. ricketti might be a species complex composed of multiple species, and further work is needed to figure out this puzzle. [ABSTRACT FROM AUTHOR]

The taxonomy of Babina sensu lato was controversial in the past decades. In this study, the phylogeny of genus Babina sensu lato was re-constructed based on genetic analysis, morphological comparison and advertisement call analysis. We found that Babina sensu stricto and previous subgenus Nidirana should be two distinct genera in the family Ranidae. N. caldwelli is confirmed to be a synonym of N. adenopleura because of the small genetic divergence and the lack of distinct morphological differences. A new species, Nidirana nankunensis sp. nov. is described based on a series of specimens collected fromMt. Nankun, Guangdong Province, China, which can be distinguished from other known congeners by having a behavior of nest construction, distinctive advertisement calls, significant divergence in the mitochondrial genes, and a combination of morphological characters. Currently, the genus Babina contains two species and the genus Nidirana contains eight species. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to evaluate the morphological changes and quantitatively assess the roughness of dentin after the ablation with a Ytterbium-Doped Potassium Yttrium Tungstate (YB: KYW) thin-disk femtosecond pulsed laser of different fluences, scanning speeds and scanning distances. Method: Twelve extracted human premolars were sectioned into crowns and roots along the cementum-enamel junction, and then the crowns were cut longitudinally into sheets about 1.5 mm thick with a cutting machine. The dentin samples were fixed on a stage at focus plane. The laser beam was irradiated onto the samples through a galvanometric scanning system, so rectangular movement could be achieved. After ablation, the samples were examined with a scanning electron microscope and laser three-dimensional profile measurement microscope for morphology and roughness study.With increasing laser fluence, dentin samples exhibited more melting and resolidification of dentin as well as debris-like structure and occluded parts of dentinal tubules. Results: When at the scanning speed of 2400mm/s and scanning distance of 24μm, the surface roughness of dentin ablated with femtosecond pulsed laser decreased significantly and varied between values of dentin surface roughness grinded with two kinds of diamond burs with different grits. When at the scanning speed of 1200mm/s and scanning distance of 12μm, the surface roughness decreased slightly, and the surface roughness of dentin ablated with femtosecond pulsed laser was almost equal to that grinded with a low grit diamond bur. Conclusion: This study showed that increased laser influence may lead to more collateral damage and lower dentin surface roughness, while scanning speed and scanning distance were also negatively correlated with surface roughness. Adequate parameters should be chosen to achieve therapeutic benefits, and different parameters can result in diverse ablation results. [ABSTRACT FROM AUTHOR]

Lomaantha phragmitis sp. nov. is described and illustrated from a specimen collected on dead culms of Phragmites communis in southern China. The fungus differs from other described Lomaantha species in its conidiophores, conidiogenous cells and conidial appendages. Conidial morphology and presence or absence of percurrent proliferation of conidiogenous cells are the main characters distinguishing species within this genus. We provided a key and synoptic table of morphological characters of all three Lomaantha species. [ABSTRACT FROM AUTHOR]

Modern grylloblattids are one of the least diverse of the modern insect orders. The thorax changes in morphology might be associated with the changes of the function of the forelegs, wing loss, changes in behavior and adaptation to habitat. As temperature is the main barrier for migration of modern grylloblattids, the range of each species is extremely limited. The potential distribution areas of grylloblattids remain unclear. A second new species of ice crawlers (Insecta: Grylloblattodea), Grylloblattella cheni Bai, Wang et Yang sp. nov., is described from China. The distribution map and key to species of Grylloblattella are given. A comparison of the thorax of extant and extinct Grylloblattodea is presented, with an emphasis on the pronotum using geometric morphometric analysis, which may reflect thorax adaptation and the evolution of Grylloblattodea. Potential global distribution of grylloblattids is inferred. Highly diversified pronota of extinct Grylloblattodea may reflect diverse habitats and niches. The relatively homogeneous pronota of modern grylloblattids might be explained by two hypotheses: synapomorphy or convergent evolution. Most fossils of Grylloblattodea contain an obviously longer meso- and metathorax than prothorax. The length of the meso- and metathorax of modern grylloblattids is normally shorter than the prothorax. This may be associated with the wing loss, which is accompanied by muscle reduction and changes to the thoracic skeleton system. Threats to grylloblattids and several conservation comments are also provided. [ABSTRACT FROM AUTHOR]

A new species of the genus Goniurosaurus (Squamata: Eublepharidae) is described from Yingde, Guangdong Province, China: Goniurosaurus yingdeensis sp. n. It can be discriminated from other known congeners by having 10-13 precloacal pores; dorsal ground color of head, body, and limbs in adults dark brown; posteriorly rounded nuchal loop situated low on the nape of the neck; five body bands between the nuchal loop and the caudal constriction; tail length and snout-vent length almost equal in individuals with original tail; the base of claws being sheathed by four scales; and short conchoidal lateral scales at claw base. First-hand data on the natural history of G. yingdeensis, and an expanded key to the genus Goniurosaurus, are provided. Being found outside the known geographical distribution of the genus Goniurosaurus, this is the first record in Guangdong Province in southern China. [ABSTRACT FROM AUTHOR]

Two new species of Stemphylium (anamor-phic Pleospora) are described on the basis of morphological characters and molecular phylogenet-ic analyses. Stemphylium phaseolina and S. variabilis were isolated respectively from diseased leaves of Phaseolus vulgaris L. in Hebei Province, China, and from diseased leaves of Alliµim sativum L. in Angres, France. The two species exhibit characteristic Stemphylium morphology but are distinct from similar species based on the morphology and development of conidia. The internal transcribed spacer (ITS) nuclear rDNA region and glyceraldehyde-3-phosphate dehydrogenase (gpd) genes were sequenced. The results of maximum parsimony (MP) and maximum likelihood (ML) phylogenetic analyses of the combined DNA sequences of these two gene regions supported S. phaseolina and S. variabilis as two distinct phylogenetic species. The taxonomic descriptions of the new species and their comparison with related species are presented, together with the phylogenetic analysis based on combined DNA sequences of ITS and gpd gene regions. [ABSTRACT FROM AUTHOR]

Newly translated tubulin molecules undergo a series of complex interactions with nascent chain-binding chaperones, including pre-foldin (PFD) and chaperonin-containing TCP-1 (Ca). By screening for oryzalin hypersensitivity. we identified several mutants of Arabidopsis that have lesions in PFD subunits. The pfd6-1 mutant exhibits a range of microtubule defects, including hypersensitivity to oryzalin, defects in cell division, cortical array organization, and microtubule dynamicity. Consistent with phenotypic analysis, pro-teomic analysis indicates several isoforms of tubulins were reduced in pfd6-1. These results support the concept that the function of microtubules is critically dependent on the absolute amount of tubulins. [ABSTRACT FROM AUTHOR]

Hg(II) Retention capacities of nine bryophyte species, collected from Jinfo Mountains (JFM) in Chongqing, China, had been investigated with special reference to the effect of morphology and elevation of moss growth. Results indicated that adsorption capacities of bryophytes for Hg(II) became stronger with the increase of multi-branches and leafy-shoots, as well as the elevation of moss growth, which was observed both in adsorption isotherm and adsorption kinetics experiments. Contrarily, the desorption kinetics showed a decrease tendency with the increase of multi-branches and leafy-shoots and the elevation of moss growth. The results demonstrated that bryophytes with higher multi-branches and leafy-shoots and higher growth elevation had a stronger adsorption capacity and a weaker desorption tendency, and therefore had a stronger retention capacity to Hg(II). The results disclosed the different relative sensitivity and retention capacity of mosses to pollution resulting from heavy metals, due to the differences in growth elevation and morphology. These should be considered when bryophytes were chosen as a tool for biomonitoring materials to environmental pollution, especially caused by Hg(II). [ABSTRACT FROM AUTHOR]

Liquid crystalline epoxy resin (LC epoxy resin) - p-phenylene di{4-[2-(2,3-epoxypropyl)ethoxy]benzoate} (PEPEB) was synthesized. The mixture of PEPEB with bisphenol-A epoxy resin (BPAER) was cured with a curing agent 4,4-diamino-diphenylmethane (DDM). The curing process and thermal behavior of this system were investigated by differential scanning calorimeter (DSC) and torsional braid analysis (TBA). The morphological structure was measured by polarizing optical microscope (POM) and scanning electron microscope (SEM). The results show that the initial curing temperature Ticu (gel point) of this system is 68.1°C, curing peak temperature Tpcu is 102.5°C, and the disposal temperature Tfcu is 177.6°C. LC structure was fixed in the cured epoxy resin system. The curing kinetics was investigated by dynamic DSC. Results showed that the curing reaction activation energy of BEPEB/BPAER/DDM system is 22.413 kJ/mol. The impact strength is increased 2.3 times, and temperature of mechanical loss peak is increased to 23°C than the common bisphenol-A epoxy resin, when the weight ratio of BEPEB with BPAER is 6 100. [ABSTRACT FROM AUTHOR]

As a long-term project aimed at developing super polyolefin blends, in this paper we summarize our work on the mechanical reinforcement and phase morphology of polyolefin blends achieved by dynamic packing injection molding (DPIM). The main feature of this technology is that the specimen is forced to move repeatedly in the model by two pistons that move reversibly with the same frequency during cooling, which result sin preferential orientation of the dispersed phase as well as the matrix. The typical morphology of samples obtained via DPIM is a shear-induced morphology with a core in the center, an oriented zone surrounding the core and a skin layer in the cross-section areas. Shear-induced phase dissolution at a higher shear rate but phase separation at low shear rates is evident from AFM examination of LLDPE/PP (50/50) blends. The super polyolefin blends having high modulus (1.9-2.2 Gpa), high tensile strength (100-120 Mpa) and high impact strength (6 times as that of pure HDPE) have been prepared by controlling the phase separation, molecular orientation and crystal morphology. [ABSTRACT FROM AUTHOR]

Highlights: [•] Surface terminations of orthorhombic Mo2C catalysts have been computed. [•] (110)-Mo and (100)-Mo terminations are stable at low carbon chemical potential. [•] (111)-Mo/C and (110)-Mo/C terminations are stable at high carbon chemical potential. [•] CO activation on Mo terminations is dissociation controlled zero-order kinetic. [•] CO activation on Mo/C terminations is adsorption controlled first-order kinetic. [ABSTRACT FROM AUTHOR]

Abstract The surface energies and the morphologies of three iron oxides (α-Fe 2 O 3 , Fe 3 O 4 , and FeO) are systematically investigated by Density Functional Theory (DFT) employing PBE and PBE+U methods. The surface energies are computed under various O chemical potential which is directly related to atmosphere condition. Compared with available experimental observations, PBE provides reasonable prediction on surface stability of all three oxides while the results of PBE+U are not well consistent with experiments for Fe 2 O 3. Based on the Wulff construction and calculated surface energies, the micro-crystal morphologies of three iron oxides are predicted at various oxygen chemical potential. Subsequently, on basis of the data of surface energies, the effect of surface free energies on phase equilibrium of iron oxides nanoparticles are investigated. These results suggest that particle sizes of nanometer have a significant influence on the thermodynamic equilibrium shifting due to their large surfaces energies contributions. This principle can guide people control the phase transition of iron oxides by adjusting surface energies contributions by changing the sizes of particles. Graphical abstract Unlabelled Image Highlights • PBE provides more reasonable prediction on surface stability of three iron oxides (α-Fe 2 O 3 , Fe 3 O 4 , and FeO) than PBE+U. • O-terminations are generally more stable than the Fe-terminations over a wide range of Δμ O for three iron oxides. • The Wulff morphology of iron oxides is a function of O chemical potential. • Particle sizes of nanometer have a significant influence on the thermodynamic equilibrium shifting. [ABSTRACT FROM AUTHOR]

• The boron chemical potential were calculated as a function of temperature, pressure and gas composition. • The bulk and surface stabilities of six iron borides are determined by the boron chemical potential. • The evolution of surface structure and morphology under dynamic conditions were predicted. • CO adsorption is weakened by surface doping of boron atom due to its electronegativity. Surface feature and its variation along with complex atmosphere are of fundamental significance to understanding the functionality of applied materials especially in heterogeneous catalysis and corrosion prevention. Here we performed a unified theoretical study on the surface structure and morphology of iron borides and their evolution under dynamic gaseous conditions by combination of density functional theory, ab initio atomic thermodynamics and Wulff construction. In particular, thermodynamic stability of iron borides and corresponding surfaces varied from the boron chemical potential (Δ μ B ) of certain atmosphere, which increases with decreasing pressure and increasing temperature and concentration of boron source. The stability of boron-rich surfaces has been improved with increasing Δ μ B , while all the Fe-rich facets of iron borides are favorable at low Δ μ B condition. Accordingly, the crystallite morphology of iron borides undergoes significant evolution upon dynamic condition. Finally, the surface properties of iron borides are carefully tested by CO adsorption which indicated the activation ability of CO is closely connected with boron triggered surface charge transfer between Fe and CO. This work was expected not only to help understand the surface structure and morphology of iron borides under realistic condition, but also provides fundamental insights into rational design of corrosion resistant and catalytic materials. [ABSTRACT FROM AUTHOR]