@article{ChenLiZhangetal.2019, author = {Chen, Shun-Gang and Li, Ji and Zhang, Fan and Xiao, Bo and Hu, Jia-Ming and Cui, Yin-Qiu and Hofreiter, Michael and Hou, Xin-Dong and Sheng, Gui-Lian and Lai, Xu-Long and Yuan, Jun-Xia}, title = {Different maternal lineages revealed by ancient mitochondrial genome of Camelus bactrianus from China}, series = {Mitochondrial DNA Part A}, volume = {30}, journal = {Mitochondrial DNA Part A}, number = {7}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {2470-1394}, doi = {10.1080/24701394.2019.1659250}, pages = {786 -- 793}, year = {2019}, abstract = {Domestic Bactrian camel (Camelus bactrianus) used to be one of the most important livestock species in Chinese history, as well as the major transport carrier on the ancient Silk Road. However, archeological studies on Chinese C. bactrianus are still limited, and molecular biology research on this species is mainly focused on modern specimens. In this study, we retrieved the complete mitochondrial genome from a C. bactrianus specimen, which was excavated from northwestern China and dated at 1290-1180 cal. Phylogenetic analyses using 18 mitochondrial genomes indicated that the C. bactrianus clade was divided into two maternal lineages. The majority of samples originating from Iran to Japan and Mongolia belong to subclade A1, while our sample together with two Mongolian individuals formed the much smaller subclade A2. Furthermore, the divergence time of these two maternal lineages was estimated as 165 Kya (95\% credibility interval 117-222 Kya), this might indicate that several different evolutionary lineages were incorporated into the domestic gene pool during the initial domestication process. Bayesian skyline plot (BSP) analysis a slow increase in female effective population size of C. bactrianus from 5000 years ago, which to the beginning of domestication of C. bactrianus. The present study also revealed that there were extensive exchanges of genetic information among C. bactrianus populations in regions along the Silk Road.}, language = {en} } @misc{CaupinHoltenQiuetal.2018, author = {Caupin, Frederic and Holten, Vincent and Qiu, Chen and Guillerm, Emmanuel and Wilke, Max and Frenz, Martin and Teixeira, Jose and Soper, Alan K.}, title = {Comment on "Maxima in the thermodynamic response and correlation functions of deeply supercooled water"}, series = {Science}, volume = {360}, journal = {Science}, number = {6390}, publisher = {American Assoc. for the Advancement of Science}, address = {Washington}, issn = {0036-8075}, doi = {10.1126/science.aat1634}, pages = {2}, year = {2018}, abstract = {Kim et al. recently measured the structure factor of deeply supercooled water droplets (Reports, 22 December 2017, p. 1589). We raise several concerns about their data analysis and interpretation. In our opinion, the reported data do not lead to clear conclusions about the origins of water's anomalies.}, language = {en} } @article{ZhangGuoChen2020, author = {Zhang, Yan-qiu and Guo, Zeng-hui and Chen, Dai-zhao}, title = {Porosity distribution in cyclic dolomites of the Lower Qiulitag Group (Upper Cambrian) in northwestern Tarim Basin, China}, series = {China geology}, volume = {3}, journal = {China geology}, number = {3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2096-5192}, pages = {425 -- 444}, year = {2020}, abstract = {Increasing interests in hydrocarbon resources at depths have drawn greater attentions to the deeply-buried carbonate reservoirs in the Tarim Basin in China. In this study, the cyclic dolomite rocks of Upper Cambrian Lower Qiulitag Group from four outcrop sections in northwestern Tarim Basin were selected to investigate and evaluate the petrophysical properties in relation to depositional facies and cyclicity. The Lower Qiulitag Group includes ten lithofacies, which were deposited in intermediate to shallow subtidal, restricted shallow subtidal, intertidal, and supratidal environments on a carbonate ramp system. These lithofacies are vertically stacked into repeated shallowing-upward, meter-scale cycles which are further grouped into six third-order depositional sequences (Sq1 to Sq6). There are variable types of pore spaces in the Lower Qiulitag Group dolomite rocks, including interparticle, intraparticle, and fenestral pores of primary origin, inter crystal, and vuggy pores of late diagenetic modification. The porosity in the dolomites is generally facies-selective as that the microbially-originated thrombolites and stromatolites generally yield a relatively high porosity. In contrast, the high-energy ooidal grainstones generally have very low porosity. In this case, the microbialite-based peritidal cycles and peritidal cycle-dominated highstand (or regressive) successions have relatively high volumes of pore spaces, although highly fluctuating (or vertical inhomogeneous). Accordingly, the grainstone-based subtidal cycles and subtidal cycle-dominated transgressive successions generally yield extremely low porosity. This scenario indicates that porosity development and preservation in the thick dolomite successions are primarily controlled by depositional facies which were influenced by sea-level fluctuations of different orders and later diagenetic overprinting.}, language = {en} } @misc{QiuKruegerWilkeetal.2016, author = {Qiu, Chen and Kr{\"u}ger, Yves and Wilke, Max and Marti, Dominik and Rička, Jaro and Frenz, Martin}, title = {Exploration of the phase diagram of liquid water in the low-temperature metastable region using synthetic fluid inclusions}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-394993}, pages = {15}, year = {2016}, abstract = {We present new experimental data of the low-temperature metastable region of liquid water derived from high-density synthetic fluid inclusions (996-916 kg m-3) in quartz. Microthermometric measurements include: (i) prograde (upon heating) and retrograde (upon cooling) liquid-vapour homogenisation. We used single ultrashort laser pulses to stimulate vapour bubble nucleation in initially monophase liquid inclusions. Water densities were calculated based on prograde homogenisation temperatures using the IAPWS-95 formulation. We found retrograde liquid-vapour homogenisation temperatures in excellent agreement with IAPWS-95. (ii) Retrograde ice nucleation. Raman spectroscopy was used to determine the nucleation of ice in the absence of the vapour bubble. Our ice nucleation data in the doubly metastable region are inconsistent with the low-temperature trend of the spinodal predicted by IAPWS-95, as liquid water with a density of 921 kg m-3 remains in a homogeneous state during cooling down to a temperature of -30.5 °C, where it is transformed into ice whose density corresponds to zero pressure. (iii) Ice melting. Ice melting temperatures of up to 6.8 °C were measured in the absence of the vapour bubble, i.e. in the negative pressure region. (iv) Spontaneous retrograde and, for the first time, prograde vapour bubble nucleation. Prograde bubble nucleation occurred upon heating at temperatures above ice melting. The occurrence of prograde and retrograde vapour bubble nucleation in the same inclusions indicates a maximum of the bubble nucleation curve in the ϱ-T plane at around 40 °C. The new experimental data represent valuable benchmarks to evaluate and further improve theoretical models describing the p-V-T properties of metastable water in the low-temperature region.}, language = {en} } @article{HoltenQiuGuillermetal.2017, author = {Holten, Vincent and Qiu, Chen and Guillerm, Emmanuel and Wilke, Max and Ricka, Jaroslav and Frenz, Martin and Caupin, Frederic}, title = {Compressibility Anomalies in Stretched Water and Their Interplay with Density Anomalies}, series = {The journal of physical chemistry letters}, volume = {8}, journal = {The journal of physical chemistry letters}, publisher = {American Chemical Society}, address = {Washington}, issn = {1948-7185}, doi = {10.1021/acs.jpclett.7b02563}, pages = {5519 -- 5522}, year = {2017}, abstract = {Water keeps puzzling scientists because of its numerous properties which behave oppositely to those of usual liquids: for instance, water expands upon cooling, and liquid water is denser than ice. To explain this anomalous behavior, several theories have been proposed, with different predictions for the properties of supercooled water (liquid at conditions where ice is stable). However, discriminating between those theories with experiments has remained elusive because of spontaneous ice nucleation. Here we measure the sound velocity in liquid water stretched to negative pressure and derive an experimental equation of state, which reveals compressibility anomalies. We show by rigorous thermodynamic relations how these anomalies are intricately linked with the density anomaly. Some features we observe are necessary conditions for the validity of two theories of water.}, language = {en} } @article{LiChenQiuetal.2019, author = {Li, Changsheng and Chen, Gangjin and Qiu, Xunlin and Gao, Meng and Gerhard, Reimund}, title = {Modified polytetrafluoroethylene}, series = {Applied physics express : APEX}, volume = {13}, journal = {Applied physics express : APEX}, number = {1}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {1882-0778}, doi = {10.7567/1882-0786/ab5b23}, pages = {5}, year = {2019}, abstract = {Three poly(tetrafluoroethylene-hexafluoropropylene-vinylidenefluoride) (TFE-HFP-VDF or THV) terpolymers (Dyneon (R)) with different monomer ratios are investigated to demonstrate the concept of "modified" PTFE for space-charge electrets. HFP and VDF monomers distort the highly ordered PTFE molecules, which effectively enhances processability and adversely affects space-charge storage. Particularly, VDF component renders the material polar and probably also more conductive, partially undermining the space-charge-storage capabilities of PTFE. Nevertheless, the terpolymer THV815 with a TFE/HFP/VDF wt\% ratio of 76.1/10.9/13 combines easy processability and relatively good space-charge stability. Our results shed light on novel concepts for space-charge electret materials with enhanced processing properties and reasonable charge-storage capabilities.}, language = {en} }