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Morella rubra, red bayberry, is an economically important fruit tree in south China. Here, we assembled the first high-quality genome for both a female and a male individual of red bayberry. The genome size was 313-Mb, and 90% sequences were assembled into eight pseudo chromosome molecules, with 32 493 predicted genes. By whole-genome comparison between the female and male and association analysis with sequences of bulked and individual DNA samples from female and male, a 59-Kb region determining female was identified and located on distal end of pseudochromosome 8, which contains abundant transposable element and seven putative genes, four of them are related to sex floral development. This 59-Kb female-specific region was likely to be derived from duplication and rearrangement of paralogous genes and retained non-recombinant in the female-specific region. Sex-specific molecular markers developed from candidate genes co-segregated with sex in a genetically diverse female and male germplasm. We propose sex determination follow the ZW model of female heterogamety. The genome sequence of red bayberry provides a valuable resource for plant sex chromosome evolution and also provides important insights for molecular biology, genetics and modern breeding in Myricaceae family.

Chemical looping combustion (CLC) with syngas, a synthesized gas mixture of CO, H 2 , CO 2 , H 2 O(g), N 2 , and H 2 S, was investigated using thermodynamic simulation, with focus on carbon deposition and sulfur evolution in CLC. Five metal oxides, such as NiO, CuO, Fe 2 O 3 , Mn 3 O 4 , and CoO, were selected as oxygen carriers for CLC application. Different influencing factors on the formation of carbon deposits were investigated, including pressure, fuel reactor (FR) temperature, oxygen excess number Φ (denoting the availability of lattice oxygen in the oxygen carrier to the fuel), and fuel gas composition. Higher temperature and larger oxygen excess number Φ inhibited the formation of carbon deposits while the pressurized condition caused the opposite. The increase of H 2 O(g) and CO 2 fraction in syngas reduced carbon deposition while, in contrast, a larger H 2 S occurrence in syngas led to more carbon deposits to be formed. A sensitivity analysis to the different factors revealed that carbon deposition was mainly determined by the FR temperature and the oxygen carriers provided while other factors played a minor role. In addition, the predominant C-bearing species and their distributions at different temperatures were thermodynamically investigated. At low FR temperature and oxygen-deficient condition (i.e., oxygen excess number Φ < 1), the predominant carbon species as solid deposits were mainly elemental carbon or carbonates for NiO, CuO, Fe 2 O 3 , and CoO while MnC 2 and MnCO 3 were the main species for Mn 3 O 4 . In terms of the evolution of sulfur in CLC with syngas containing a basic composition of CO, N 2 , H 2 , and H 2 S, the low pressure, high temperature, and adequate lattice oxygen would make more sulfur species form in the gas phase. After that, CO 2 and H 2 O(g) were introduced into the syngas, and they were found to possibly serve as additional oxidizers to convert H 2 S into SO 2 . The oxidation function of CO 2 was slightly stronger than that of steam. Again, the evolution and distribution of various sulfur species was studied. For four metal oxides (NiO, Fe 2 O 3 , Mn 3 O 4 , and CoO), the most possible solid sulfur compounds were Ni 3 S 2 , Fe 0.84 S, MnSO 4 , and Co 0.89 S, respectively. But for CuO, at Φ < 1, Cu 2 S was the main solid sulfur compound while at Φ > 1 CuSO 4 and Cu 2 SO 4 dominated.

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