| 1 | A Taxonomic Re-Assessment of the Novispathodus waageni Group and Its Role in Defining the Base of the Olenekian (Lower Triassic)显示文摘Lower Triassic conodont biostratigraphy has been well studied around the world in the past decades, but the Induan-Olenekian boundary(IOB) remains undecided. The Novispathodus waageni group has been taxonomically re-assessed based on abundant new materials from the Jianshi and Chaohu sections, South China. New study shows that Nv. waageni typically possesses:(1) an approximately equi-dimentional P1 blade element,(2) an accurate upper profile with denticle height descending in both directions,(3) a denticulated posterior edge(lower denticles posterior of the highest denticle), and(4) a round basal cavity outline. Of the three proposed subspecies of the waageni species, both Nv. waageni waageni(Sweet, 1970) and Nv. w. eowaageni(Zhao and Orchard, 2005) are valid, and the former differs clearly from Nv. w. eowaageni in having(1) a slightly higher length/height ratio(holotype=1.30 : 1.23),(2) a thicker blade, sometimes with medial thickening,(3) fewer(broader) denticles per unit length,(4) generally recurved denticles, not straight and upright,(5) highest denticles closer to posterior,(6) common differentiation of a posterior cusp, and(7) more sinuous basal profile, with increased posterior upturning. A third subspecies illustrated as Nv. waageni n. subsp. A sensu Goudemand, 2014 is not conspecific with older individuals of Nv. w. eowaageni, and also cannot be assigned to the Nv. waageni group. Abundant new materials demonstrate a clear ontogenic process for Nv. w. eowaageni, indicating that Nv. w. eowaageni occurring in the Induan-Olenekian boundary(IOB) succession is rather stable. Small, earlier individuals(i.e., those from Bed 225 in Jianshi) are referred to as Nv. w. eowaageni Morphotype A, and are thought to have likely evolved from Ns. dieneri Morphotype 3, and to be the precursor of mature elements of Nv. w. eowaageni. The first appearance datum of Nv. w. eowaageni therefore is an ideal mark defining the IOB. | Zhengyi Lyu Michael J Orchard Zhong-Qiang Chen Laishi Zhao Lei Zhang Xiumei Zhang | 2018 | Journal of Earth Science2018，29，4： | 2 |
| 2 | Nacre-liked material with tough and post-tunable mechanical properties显示文摘Biomaterials,often imparted time-dependent mechanical properties,which are promising in fields rang-ing from sensors to robotics.Here,a facile method was proposed to fabricate post-tunable mechanical properties composites based on hydrogels and ceramic nanofiller.The wide tunable range of Young’s modulus(27.3 kPa to 3.5 GPa)and ultimate stress(173 kPa to 102 MPa)can be achieved by combining solvent absorption and evaporation process with platelets reinforcement effect.Additionally,a large fracture toughness(∼32,000 J m^(-2))is obtained as a result of the nacre-liked“brick and mortar”structure introduced by shear force during fabrication.The superior flexibility and designability of this material were demonstrated via actuators,portable structure,and metamaterials.Above all,this study provides a new thought to fabricate tough materials with post-tunable mechanical properties. | Zhengyi Mao Mengke Huo Fucong Lyu Yongsen Zhou Yu Bu Lei Wan Lulu Pan Jie Pan Hui Liu Jian Lu | 2022 | Journal of Materials Science & Technology2022，，19： | 0 |
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