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The unique continuous extrusion-based severe plastic deformation approaches were proposed recently to process high-performance magnesium (Mg) alloys, while the in-depth deformation mechanisms under such complicated thermomechanical conditions were not well understood. In the present work, the fundamental deformation behaviors of AZ61 Mg alloy from 25 to 400 °C were firstly examined under uniaxial compression deformation. Then the deformation mechanisms and microstructural characteristics of AZ61 Mg alloy during continuous expansion extrusion forming (CEEF) were systematically investigated by microstructural observations, finite element and cellular automata simulations. The results showed that the continuous evolutions of temperature, larger strain level and complex stress state with strain rate range of 0 ∼ 5.98 s−1 during CEEF brought the distinctive dynamic recrystallization behaviors and texture development in AZ61 Mg alloy, which were different to that of uniaxial compression deformation. In details, a remarkable grain refinement was achieved via CEEF processing due to the simultaneous actions of continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX). Gradually enhanced CDRX were observed from center to edge region, which had significant effects on the texture distribution and texture strength. The c-axis of most grains rotated under distinctive shear strain following parabolic metal flow, resulting in stable fiber texture. In addition, the evolution of the internal texture of the alloy led to an obvious increase in the Schmid factor for the activation of basal 〈c + a〉 slip system.

Achalinus sheni Ma, Xu, Qi, Wang, Tang, Huang & Jiang, 2023 was originally described based on only male specimens from Lianyuan City and Nanyue District, Hunan, China. So far, no information on the females of this species is available. After molecular systematics and morphological characters of recently collected specimens from Xinshao County, Hunan, several specimens (3 males and 1 female) were identified as this species. Therefore, we provided supplementary descriptions of the female characteristics of this species in this study. Meanwhile, we extended the description of this species.

A new species of xenodermid snake, Achalinus nanshanensis H. Li, L.-Q. Zhu, Z.-Q. Zhang & X.-Y. Mo, sp. nov., is described based on three specimens collected from Nanshan National Park and Tongdao County of southwest Hunan Province. This new species is genetically distinct amongst its congeners with the mitochondrial COI uncorrected p-distance ranging from 4.4% (in A. yangdatongi) to 17.7% (in A. meiguensis). In addition, this new species can be distinguished from its congeners by a combination of the following morphological characters: (1) dorsal scales with 23 or 25 rows throughout and strongly keeled; (2) tail relatively longer so that TaL/ToL = 0.215–0.248; (3) length of suture between internasals significantly longer than that between prefrontals, LSBI/LSBP = 1.66–1.84; (4) single loreal scale present; (5) SPL 6 in number, with the fourth and fifth contacting eye; (6) IFL 6 in number, with the first three touching the first pair of chin shields; (7) TMP is 2-2-4/2-2(3)-4, with the anterior pair elongated and in contact with the eye; (8) ventrals 2 + 147–158; (9) subcaudals 64–77, unpaired; (10) dorsal body brownish black, with a bright yellow neck collar extending to the head and abdomen in the occipital region. The recognition of the new species increases the number of described Achalinus species to 28, of which 21 are found in China.

Abstract Background Rice husk is the most silicon-rich renewable biomass and can be used as a raw material for producing silicon-based materials. With the increasing interest in utilizing rice husk as a renewable resource, the development of a robust silica extraction method is required. In this study, a one-pot alkali hydrothermal and ball-milling continuous silica extraction method was developed at the pilot scale. Results Three residence times (50, 100, and 150 min) were selected to compare the performance of the continuous extraction process depending on the residence time. The silica production was 4.09, 2.67, and 2.22 kg day−1 while the silica extraction yield was 52.8, 69.1, and 86.0% at resident times of 50, 100, and 150 min, respectively. The energy consumption for producing 1 kg of silica from rice husk was 51.6, 47.7, and 47.4 MJ kg−1 at resident times of 50, 100, and 150 min, respectively. The one-pot continuous silica extraction process was performed for 150 h to verify the stability of the process. During long-term operation, the process exhibited a constant solid content and stable silica extraction yield. The silicate solution obtained by the one-pot continuous process was successfully used to synthesize size-controlled spherical silica particles, which had a purity of 99.1 wt% and amorphous structure. Conclusions Overall, this study presents a novel continuous silica extraction method for the efficient recovery of silica from rice husk-based biorefineries. Graphical abstract