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In this work, the effects of in-plane shear stress on the thermal conductivities of two important kinds of graphene configurations (rectangular graphene and annular graphene) are investigated using molecular dynamics simulations. The various strain angles are set as θ = 0°, 3°, 5°, 10°, and 15° for rectangular graphene and θ = 0°, 3°, 5°, and 8° for annular graphene. A spectral energy density approach is applied to carry out phononic analyses of the two configurations under in-plane shear stress for the first time. It is found that for rectangular graphene, the thermal conductivity shows a significant decreasing trend from 239.6 to 79.1 W m−1 K−1 with the θ increasing from 0° to 15°. Besides, the application of shear stress can significantly widen the energy bands of branches, which indicates shorter phonon lifetimes. Further phononic analysis shows that most of the phonon scattering caused by in-plane shear stress emanates from the in-plane mode, which is an updated conclusion in this field. On the other hand, the thermal conductivity of annular graphene also shows a decreasing evolution with the increasing strain angles, but phonon transport in rectangular graphene is more susceptible to shear stress than in annular graphene due to a stronger phonon-boundary scattering in the latter configuration. In this work, the monotonically decreasing trends of the thermal conductivities of both graphene configurations with the increasing strain angle are different from the V-shape trend reported in the literature. Based on phononic analyses, it can be concluded that an abnormal increase of the thermal conductivities at a low shear stress can be attributed to the application of the AIREBO potential model in the literature. [ABSTRACT FROM AUTHOR]

Sclerotinia stem rot is a broad-spectrum threat to rapeseed production, and Brassica juncea contains abundant genetic resources for resistance against Sclerotinia sclerotiorum. Therefore, it is of great significance to carry out screening, localization, and exploration of resistance loci for sclerotinia stem rot in Brassica juncea germplasm resources for the breeding of Sclerotinia-resistant rapeseed. In this study, the S. sclerotiorum resistance of Brassica juncea germplasm resources collected from various regions in Yunnan Province was evaluated under three different growth environments, and a whole-genome association analysis of S. sclerotiorum resistance loci was conducted based on the resequencing data of 91 Brassica juncea germplasm materials. According to the results of leaf identification under in vitro conditions in the three growth environments, one highly resistant germplasm material J7667 and one relatively resistant germplasm material J047 were selected. The resequencing data of the 91 materials were aligned to the reference genome of Brassica juncea for variation detection analysis, resulting in the detection of 11 337 871 SNPs and 40 170 Indels distributed on the 18 chromosomes of Brassica juncea. After data filtering, 403 211 high-quality SNPs were obtained. The phenotypic data of in vitro leaves, in vitro stems, and stem resistance to S. sclerotiorum of the 91 materials under the three growth environments were subjected to whole-genome association analysis using two analysis software, Emmax and Tassel. In the in vitro leaves, both analysis methods identified a total of 62 significantly associated SNP loci with resistance in the three different growth environments, including 23 and 39 significantly associated SNP loci in the Luoping winter sowing and Xiaoshao winter sowing environments, respectively, while no resistance loci were detected in the Xiaoshao summer sowing environment. In the stem of Luoping winter sowing, both methods detected 3 significantly associated SNP loci with resistance, while no significant SNP was detected in the stem of Xiaoshao summer sowing. In the Tassel method, closely located resistance SNP loci were detected on chromosomes A2, A8, and B2 in Luoping winter sowing and Xiaoshao winter sowing, while in the Emmax method, closely located resistance SNP loci were detected on chromosomes B5 and B8 in Luop-ing winter sowing and Xiaoshao winter sowing. In addition, this study mapped the previously identified S. sclerotio-rum resistance QTL loci and the resistance loci identified in this study to the reference genome of Brassica juncea. It was found that the resistance QTL intervals identified in this study (XLRA2-2, XLRA1-4) overlapped with the reported resistance QTL loci Sll2 and qsr10-1, respectively. [ABSTRACT FROM AUTHOR]

Germanium extraction from a high acid leach solution of zinc replacing slag by a new extractant, HBL101, was tested based on the current research status on extracting germanium from zinc smelting slag in hydrometallurgy. Investigations were performed on the effects of feed acidity, extractant concentration, extraction time, extraction phase ratio and temperature on the extraction, the effects of NaOH concentration, stripping time, stripping phase ratio and temperature on the stripping of germanium, and the conditions of extractant transformation. The results show that with 30% HBL101 in 70% sulphonated kerosene (volume fraction) as an extract-ant, the extraction rate of germanium from the solution with 113.2 g·L-1 H2SO4 reaches 98.57% in five-stage counter current extrac-tion with a volume ratio of oil phase to aqueous phase, O/A ratio, of 1:4 at 25℃ for 20 min. Germanium in the loaded organic can be selectively stripped using a 150 g·L-1 NaOH solution and the stripping rate reaches 98.1% in five-stage counter current stripping with an O/A ratio of 4:1 at 25℃ for 25 min. After germanium stripping, copper in the loaded organic can be stripped using a 200 g·L-1 H2SO4 solution and the stripping rate of copper reaches 99.75% in five-stage counter current stripping with an O/A ratio of 2:1 at 25℃ for 20 min. The extractant returns to extraction circularly.