Browsing by Author "Luo, Y"

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    Enigmatic human remains from the Pleistocene-Holocene transition of southwest China and the complex evolutionary history of east Asians
    (Australian Geosciences Council, 2012-08-05) Curnoe, D; Ji, X; Herries, AIR; Bai, K; Taçon, PSC; Bao, Z; Fink, D; Zhu, Y; Hellstrom, JC; Luo, Y; Cassis, G; Su, B; Wroe, S; Hong, S; Parr, WCH; Huang, S; Rogers, N
    The Upper Pleistocene hominin fossil record of East Asia is poorly known due to a scarcity of well-described, reliably classified and accurately dated fossils. In 2008, we started a joint project involving six Chinese and five Australian institutions to examine the later Pleistocene human record from southwest China. The region has been identified from genetic research as a hotspot of human diversity, and has yielded a number of human remains thought to derive from Pleistocene deposits. We prepared, reconstructed, described and dated a new partial skeleton from a consolidated sediment block collected in 1979 from the site of Longlin Cave (Guangxi Province). We also undertook new excavations at Maludong (Yunnan Province) to clarify the stratigraphy and dating of a large sample of mostly undescribed human remains from the site. Both samples probably derive from the same population, exhibiting an unusual mixture of modern human traits, characters probably plesiomorphic for later Homo, and some unusual features. We dated charcoal with AMS radiocarbon dating and speleothem with the Uranium-series technique and the results show both samples to be from the Pleistocene-Holocene transition: ∼14.3–11.5 ka. At nearby sites, some modern humans had already begun the economic transition to agriculture by this time. We suggest the Longlin-Maludong humans represent either a late-surviving archaic population or a previously unknown modern human group who colonised East Asia probably without leaving descendants. The archaeological record of Maludong indicates these humans were engaging in complex behaviours, including ochring bones and shells and manufacturing containers from human skulls.
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    Further geological and palaeoanthropological investigations at the Maludong hominin site, Yunnan Province, Southwest China
    (Springer Nature, 2013-08-28) Ji, X; Curnoe, D; Bao, Z; Herries, AIR; Fink, D; Zhu, Y; Hellstrom, JC; Luo, Y; Tacon, PSC
    Three-dimensional mapping and section work undertaken by us in 2008 have identified 11 stratigraphic units at Maludong site. AMS radiocarbon dating of charcoal established an accurate and internally consistent age profile for the sequence of 17.8±0.2 ka to 13.2±0.1 ka. Archaeomagnetic analysis showed changes in externally derived pedogenically enhanced material consistent with a warming in climate between the cold period of Henrich Event 1 and the Bølling-Allerød interstadial. Human remains recovered during the 1989 excavation were derived from a deposit dating to this interstadial, or between 14.3±0.3 ka and 13.5±0.1 ka. Anthropogenic features, including burnt rocks, baked sediment and thick charcoal and ash layers, were identified and examined through archaeomagnetic analysis. Two monkey fossils are described here, one of them being reassigned from Macaca robustus to M. aff. M. assamensis. They confirm the young age of the site and also show signs of anthropogenic alteration in the form of burning. Additional human cranial remains are reported for the first time and new data are provided for some specimens described previously. A range of new features is identified that strengthen the affinities of the Maludong remains to archaic humans. The presence of this globally unique mosaic of archaic and modern features raises important questions about human evolutionary history in East Asia during the Late Upper Pleistocene. © The Authors - Open Access
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    Gamma radiation effects on the performance of FIR-based fiber-optic temperature sensors
    (Institute of Electrical and Electronics Engineers, 2019-11-02) Fan, D; Xiao, G; Chu, Y; Ma, Z; Wei, S; Zhang, B; Tian, Y; Fu, X; Obbard, EG; Davies, JB; Luo, Y; Peng, GD
    The gamma radiation effect on the performance of fluorescence intensity ratio-based fiber-optic temperature sensors is studied. The results indicate such temperature sensors are promising for integration in gamma radiation environment.
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    Synergistic Pt doping and phase conversion engineering in two-dimensional MoS2 for efficient hydrogen evolution
    (Elsevier, 2021-06) Li, Y; Gu, QF; Johannessen, B; Zheng, Z; Li, C; Luo, Y; Zhang, ZY; Zhang, Q; Fan, H; Luo, WB; Liu, B; Dou, SX; Liu, HK
    Molybdenum disulphide (MoS2) is proven to be a promising catalyst for hydrogen evolution reaction (HER), but the HER performance of reported MoS2-based catalysts is still limited by its poor conductivity and low density of active sites. Herein, a Pt-doped MoS2 (Pt@MoS2) catalyst is synthesized by a potential-cycling method, which introduces the Pt dopant into the MoS2 lattice and achieves partial 2H to 1T phase conversion of MoS2 simultaneously. Benefitting from the optimized geometric and electronic structure of MoS2, the Pt@MoS2 exhibits a low overpotential of 88.43 mV at 10 mA cm−2, which is decreased by two-thirds as compared to that of the pristine MoS2. A comprehensive study reveals the position and the contribution of Pt atom in electronic structure modulation of MoS2. Theoretical calculations further reveal that the S atom adjacent to the Pt in MoS2 acts as the most active site for HER, and possesses a small hydrogen adsorption free energy (∆GH*) of ~ 0.04 eV, similar to the benchmark Pt catalyst. This study opens up a new avenue for designing MoS2 and other transition metal dichalcogenide-based electrocatalysts with enhanced HER performance, as well as providing in-depth understanding on the HER mechanism in external metal-activated MoS2 catalyst. © 2021 Elsevier Ltd.