A newly emerged duck parvovirus, which causes beak atrophy and dwarfism syndrome (BADS) in Cherry Valley ducks, has appeared in Northern China since March 2015. To explore the genetic diversity among waterfowl parvovirus isolates, the complete genome of an identified isolate designated SDLC01 was sequenced and analyzed in the present study. Genomic sequence analysis showed that SDLC01 shared 90.8%–94.6% of nucleotide identity with goose parvovirus (GPV) isolates and 78.6%–81.6% of nucleotide identity with classical Muscovy duck parvovirus (MDPV) isolates. Phylogenetic analysis of 443 nucleotides (nt) of the fragment A showed that SDLC01 was highly similar to a mule duck isolate (strain D146/02) and close to European GPV isolates but separate from Asian GPV isolates. Analysis of the left inverted terminal repeat regions revealed that SDLC01 had two major segments deleted between positions 160–176 and 306–322 nt compared with field GPV and MDPV isolates. Phylogenetic analysis of Rep and VP1 encoded by two major open reading frames of parvoviruses revealed that SDLC01 was distinct from all GPV and MDPV isolates. The viral pathogenicity and genome characterization of SDLC01 suggest that the novel GPV (N-GPV) is the causative agent of BADS and belongs to a distinct GPV-related subgroup. Furthermore, N-GPV sequences were detected in diseased ducks by polymerase chain reaction and viral proliferation was demonstrated in duck embryos and duck embryo fibroblast cells.

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IntroductionThe selective hydrogenation of a,b-unsaturated carbonyl compounds is of theoretical and practical significance. [1][2][3] For instance, the hydrogenation of cinnamaldehyde (CAL) can produce cinnamal alcohol (COL), hydrocinnamaldehyde (HALD), and/or hydrocinnamal alcohol (HALC; Scheme 1), but the selective production of COL is difficult because the hydrogenation of the C=C bond is thermodynamically favored over that of the C=O moiety. [1,4] Moreover, acetals and other unidentified high-molecular-weight compounds can also be produced in large quantities in these reactions. [4,5] Although much research has already been focused on this issue, the selective hydrogenation of a,b-unsaturated aldehydes remains a challenge.The selective hydrogenation of a,b-unsaturated aldehydes toward the unsaturated alcohol can be achieved with homogeneous catalysts such as metal hydrides, aluminium isopropoxide, and others. [6,7] However, it is desirable to develop an equal-ly selective heterogeneous catalyst as these are easier to handle and separate from the products. To this end, a large number of studies on supported catalysts based on Pt, Rh, Au, Ru, and Pd active phases have been reported. [8][9][10][11][12] Cordier et al. reported that the selectivity for COL production from CAL hydrogenation follows the sequence Os > Ir > Pt > Ru > Rh > Pd, [13,14] a trend that was correlated with the width of the dband of the metal (Pd < Pt < Ir, Os). Many other studies have targeted supported Pt catalysts because of their high activity and moderate selectivity.In addition to the different metals that can be used to control selectivity in CAL hydrogenation processes, the supports may play an important role to define the selectivity. Indeed, differences in activity and selectivity may be obtained by varying the nature of the interaction between the support and nanoparticles (NPs). For instance, the selectivity toward COL production may be enhanced by using reducible oxides such as CeO 2 , [15] MnO 2 , [16] SnO 2 , [17] TiO 2 , [18] and ZnO [19] because of the electron transfer that takes place between these supports and Catalysts made of Pt nanoparticles dispersed on graphene (X wt %Pt/G, X = 2.0, 3.5, and 5.0) were prepared and characterized by XRD, Raman spectroscopy, BET surface area measurements, TEM, and X-ray photoelectron spectroscopy (XPS), and a 3.5 wt % Pt supported on Vulcan Carbon catalyst (3.5 wt %Pt/ VC) was included as a reference. Although the mean Pt nanoparticle size is approximately 4.4 nm for all X wt %Pt/G and 3.5 wt %Pt/VC catalysts, cinnamal alcohol was produced with high selectivity only with the graphene-supported catalysts:92 % conversion and 88 % selectivity toward cinnamal alcohol were obtained with 3.5 wt %Pt/G. This catalyst also showed good stability in recycling tests. The good selectivity observed with the graphene-based catalysts is attributed to the higher fraction of reduced surface Pt 0 atoms seen on the surface of the Pt nanoparticles (determined by XPS). This interpretation is consistent with D...

In this study, nano-structure ceria with three different morphologies (nanorod, nanoparticle and flake) have been prepared by hydrothermal and solvothermal methods. The ceria samples were deeply characterized by XRD, SEM, TEM, H2-TPR, XPS and in-situ DRIFTS, and tested for soot combustion in absence/presence NO atmospheres under loose and tight contact conditions. The prepared ceria samples exhibit excellent catalytic activities, especially, the CeO2 with nanorod (Ce-R) shows the best catalytic activity, for which the peak temperature of soot combustion (Tm) is about 500 and 368 °C in loose and tight contact conditions, respectively. The catalytic activity for Ce-R is higher than that of the reported CeO2 catalysts and reaches a level that of precious metals. The characterization results reveal that the maximal amounts of adsorbed oxygen species on the surface of the nanostructure Ce-R catalyst should be the crucial role to decide the catalytic soot performance. High BET surface area may also be a positive effect on soot oxidation activity under loose contact conditions.

The Ni0.4Mn0.6Ti10 catalyst exhibits excellent SO2 resistance, high NO conversion and N2 selectivity in the range of 190–360 °C even in the presence of 100 ppm SO2 and 15% H2O under a GHSV of 40 000 h−1 due to the interaction among Mn, Ni and Ti oxides.

Amorphous Ce0.3TiOx exhibits a high activity and sulfur resistance for NH3-SCR of NO due to the strong interactions between Ce and Ti.

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