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New Schizolepis Fossils from the Early Cretaceous in Inner Mongolia, China and its Phylogenetic Position

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Acta Geologica Sinica(English Edition) 2013年第5期87卷 1250-1263页

作者： XU Xiaohui LI Ruiyun DONG Chong wang qiujun JIN Peihong SUN Bainian School of Earth Sciences&Key Laboratory of Mineral Resources in Western China (Gansu Province) Lanzhou University

Three Schizolepis species collected from the Lower Cretaceous layer of the Huolinhe Basin, Inner Mongolia, China are described. These fossils are Schizolepis longipetiolus Xu XH et Sun BN sp. nov., which is a new species, Schizolepis cf. heilongjiangensis Zheng et Zhang, and Schizolepis neimengensis Deng. The new species is a well-preserved female cone, slender and cylindrical in shape. The seed-scale complexes have long petioles and are arranged on the cone axis loosely and helically. The seed scales are divided into two lobes from the base. Each lobe is semicircular or elongate ligulate in shape, widest at the middle or the lower middle part, with an obtuse or bluntly pointed apex. The inner margin is almost straight and the outer margin is strongly arched. On the surface of the lobe, there are longitudinal and somewhat radial striations from the base to the margin. The seed is borne on the adaxial surface at the base or middle of each lobe. Schizolepis was estabfished in 1847, and, although more than twenty species have been discovered and reported, its phylogenetic position is controversial because of the imperfection of fossils. Most authors have considered there to be a close evolutionary relationship between Schizolepis and extant Pinaceae. Here, we analyze characteristics and compare Schizolepis with Picea crassifolia Kom, which is morphologically most similar to Schizolepis. The results indicate that the genus probably has a distant evolutionary relationship with extant Pinaceae. A detailed statistical analysis of the global paleogeographic distribution of Schizolepis showed that all the fossils of this genus appeared in strata ranging from the Upper Triassic to the Lower Cretaceous in the North Hemisphere, being rare in the Upper Triassic and Lower Jurassic, but being very common from the Middle Jurassic to the Lower Cretaceous, and particularly abundant in the Lower Cretaceous. According to the statistical results, we speculate that the genus originated i

关键词： Schizolepis systematic evolution paleogeographic distribution Early Cretaceous cause of extinction Inner Mongolia

Anion competition for Li^(+)solvated coordination environments in poly(1,3 dioxolane)electrolyte to enable high-voltage lithium metal solid-state batteries

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Journal of Energy Chemistry 2024年第9期96卷 633-641页

作者： qiujun wang Yanqiang Ma Xiaomeng Jia Di Zhang Zhaojin Li Huilan Sun Qujiang Sun Bo wang Li-Zhen Fan Hebei Key Laboratory of Flexible Functional Materials School of Materials Science and EngineeringHebei University of Science and TechnologyShijiazhuang 050000HebeiChina Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China

Gel-based polymer electrolytes are limited by the polarity of the residual solvent,which restricts the coupling-breaking behaviour during Li^(+)conduction,resulting in the Li^(+)transport kinetics being greatly ***,we designed anion competitive gel polymer electrolyte(ACPE)by introducing lithium difluoro(oxalato)borate(LiDFOB)anion into the 1,3-dioxolane(DOL)in situ polymerisation *** enhances the ionic dipole interaction between Li^(+)and the solvent molecules and synergizes with Li^(+)across the solvation site of the polymer ethylene oxide(EO)unit,combination that greatly improves the Li^(+)transport *** a result,ACPE exhibits 1.12 mS cm^(−1)ionic conductivity and 0.75 Li^(+)transfer number at room ***,this intra-polymer solvation sheath allows preferential desolvation of DFOB−,which contributes to the formation of kinetically stable anion-derived interphase and effectively mitigates side *** results demonstrate that the assembled Li||NCM622 solid-state battery exhibits lifespan of over 300 cycles with average Coulombic efficiency of 98.8%and capacity retention of 80.3%.This study introduces a novel approach for ion migration and interface design,paving the way for high-safety and high-energy-density batteries.

关键词： Li-metal batteries Poly(1,3-dioxolane) In situ polymerization Solid-state polymer electrolytes Anion competition

Bamboo Leaf and Pollen Fossils from the Late Miocene of Eastern Zhejiang,China and their Phytogeological Significance

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Acta Geologica Sinica(English Edition) 2014年第4期88卷 1066-1083页

作者： wang qiujun MA Fujun YANG Yi DONG Junling wang Haofei LI Ruiyun XU Xiaohui SUN Bainian School of Earth Sciences & Key Laboratory of Mineral Resources in Western China (Gansu Province) Lanzhou University

Fossil bamboo leaves and pollen from Upper Miocene deposits of the Shengxian Formation in Tiantai and Ninghai counties, eastern Zhejiang, China represent a rare record in Asia. The distinctive pseudopetiole and parallel venation of the leaf blades and the clearly thickened annulus of the pollen aperture place them in the subfamily Bambusoideae. Morphological analysis supports the determination of these fossil leaves as belonging to the genus Bambusium and two new species are described. Bambusium latipseudopetiolus Q.J. wang et B.N. Sun sp. nov. has a distinctly wide pseudopetiole of 0.23 cm in width and 0.40 cm in length, several vascular bundles on parallel veins, and 5-8 lateral veins on both sides of the midrib. Bambusium longipseudopetiolus Q.J. wang et B.N. Sun sp. nov. has a distinctly long pseudopetiole of 0.60 cm in length and 0.10 cm in width, several vascular bundles on the pseudopetiole, and 6 lateral veins on both sides of the midrib. Pollen grains from the same layer provide additional evidence of bamboos. They are characterized by 32.0-51.0 μm in diameter, a round pore 3.0-4.0 μm in diameter with a broad thickened annulus 2.5-3.5 μm around, and several conspicuous secondary folds on the exine surface. The morphological analysis leads to their assignment to Graminidites bambusoides Stuchlik. These fossils are important for the study of bamboo phytogeography in China. They demonstrate that there were bamboos growing in southeastern China during the Late Miocene and that bamboos in Zhejiang begin to diversify no later than the Late Miocene. In combination with bamboo fossils from other places, it seems that bamboos had a wide distribution across southern China during the Miocene, ranging from southwestern Yun＇nan to southeastern Zhejiang.

关键词： Paleobotany Palynology Phytogeography Bambusoideae Late Miocene Zhejiang province

Synergistically enabling the interface stability of lithium metal batteries with soft ionic gel and garnet-type Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)ceramic filler

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Journal of Materiomics 2023年第3期9卷 568-576页

作者： qiujun wang Weiqi Zhu Ya Su Di Zhang Zhaojin Li Huan wang Huilan Sun Bo wang Dan Zhou Li-Zhen Fan Hebei Key Laboratory of Flexible Functional Materials School of Materials Science and EngineeringHebei University of Science and TechnologyShijiazhuang050000China Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing100083China

Lithium metal batteries based on solid electrolytes are considered as promising candidates with high energy density and ***,the weak solid-solid contact between electrolyte and electrode can easily lead to interface instability and lithium ions discontinuous migration,which seriously reduces the electrochemical performance of the ***,we construct a soft gel interfacial layer to improve the stability of the solid-solid interface between electrolyte and electrode by means of polyester-based monomers and imidazole-based ionic *** on this,garnet-type Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)particles as inorganic ceramic filler were introduced in the layer to obtain composite electrolytes with high ionic conductivity(up to 1.1×10^(-3)S/cm at 25℃).As a result,the assembled lithium symmetric battery of Li|THCE-15%LLZTO|Li suggests excellent cycling stability with 700 h at 0.1 mA/cm^(2)at 50℃,and the lithium metal batteries of LFP|THCE-15%LLZTO|Li delivers high initial discharge capacity of 128.2 mA·h/g with capacity retain of 75.48%after 150 cycles at 2 *** work paves a new route to build safe and stable lithium metal batteries with synergistic introduction of composite electrolytes between electrolyte and electrode using soft gel interfacial layer and inorganic filler.

关键词： Lithium metal batteries Ionic liquid In-situ polymerization Soft interfacial layer Composite electrolyte

Exploring the role of solvents in structural regulation during ultrasonic synthesis of Co/Ni-layered double hydroxide for oxygen evolution reaction

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Materials Reports(Energy) 2024年第4期4卷 48-56,I0002页

作者： Zhaojin Li Qian Ma Zezhao Li Di Zhang Qujiang Sun qiujun wang Huilan Sun Bo wang Key Laboratory of Flexible Functional Materials School of Materials Science and EngineeringHebei University of Science and TechnologyHebei050018PR China

Cobalt-based layered double hydroxides(LDHs)are highly sought after by researchers due to their low-cost,high efficiency and stability for oxygen evolution reaction(OER)in water *** OER performance of these LDHs is closely related to their morphology and electronic ***,there is a lack of theory on how to control reaction conditions to regulate the *** this paper,the growth mechanism of LDH prepared in different solvents is thoroughly ***,the Co/Ni-LDHs exhibiting a 3D hierarchical flower-like structure were synthesized with normal alcohol as a solvent,meanwhile,the thickness of the LDHs can be controlled by the molecular weight of the normal *** adjusting the suitable Co/Ni ratio and solvent,the Co/Ni0.050-LDH-Me was synthesized and exhibited excellent OER *** 10 mA cm^(-2),the overpotential of Co/Ni0.050-LDH-Me is 307 mV,and the Tafel slope is 76.5 mV dec^(-1).

关键词： Oxygen evolution reaction Electrocatalysts Layered double hydroxide Transition metal

A two-step strategy for constructing stable gel polymer electrolyte interfaces for long-life cycle lithium metal batteries

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Journal of Materiomics 2022年第5期8卷 1048-1057页

作者： qiujun wang Pin Zhang Weiqi Zhu Di Zhang Zhaojin Li Huan wang Huilan Sun Bo wang Li-Zhen Fan Hebei Key Laboratory of Flexible Functional Materials School of Materials Science and EngineeringHebei University of Science and TechnologyShijiazhuang050018China Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing100083China

Due to the high reactivity between the lithium metal and traditional organic liquid electrolyte,the reaction of lithium metal electrode is usually uneven and there are also unexpected side ***,construction of a stable solid electrolyte interface(SEI)is highly essential to improve the performance of lithium metal ***,a sandwich-like gel polymer electrolyte(GPE)is accurately prepared by in-situ polymerization of Polyacrylonitrile(PAN)nanofiber membrane with trihydroxymethylpropyl trimethylacrylate(TMPTMA)and 1,6-hexanediol diacrylate(HDDA).The resulting GPE with a tightly cross-linked gel skeleton exhibits high ionic conductivity and electrochemical window of 5.6 V versus Li/Li^(+).In particular,the pretreatment of Li metal anode can improve the interfacial wettability,and the synergy of the chemically pretreated Li metal anode surface and the GPE can electrochemically in situ generate SEI with compositionally stable and fluorine-rich inorganic *** to these unique advantages,the interfacial compatibility between the GPE and lithium metal is greatly ***,the formed SEI can inhibit the formation of lithium dendrites,and decomposition of GPE would be *** assembled Li-FEC|GPE|LiFePO_(4) full cell shows a high initial discharge capacity of 157.1 mA h g^(-1),and maintains a capacity retention of 92.3%after 100 cycles at 0.2C.

关键词： Gel polymer electrolyte Pre-lithiation Lithium-metal batteries In-situ polymerization

Cuticular anatomy of Comia(Pteridospermae) from the Upper Permian of Yumen in Gansu Province, Northwestern China, and palaeoatmospheric CO_2 reconstruction

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科学通报 2013年第S1期58卷 185-192页

作者： DONG Chong XU XiaoHui wang qiujun MA FuJun YANG Yi DAO KeQun SUN BaiNian SUN KeQin School of Earth Sciences and Key Laboratory of Mineral Resources in Western China Lanzhou University School of Earth Sciences and Resources China University of Geosciences

Comia macrofossils have been widely known from rocks of the Late Permian age in the Angaran and Cathaysian Palaeobiogeographic regions. However, the epidermal structure of the genus has not been reported. The new material with wellpreserved cuticles obtained from the Late Permian Sunan Formation in the west of Gansu Province, Northwestern China allows a new species to be attributed to this genus, namely Comia dashankouensis Dong C et Sun BN sp. nov. The cuticular features of the genus are described, including the general structures of lower and upper cuticles, stomata, and papillae. The stomatal density(SD) and stomatal index(SI) of fossil cuticles are routinely used today as a proxy in the reconstruction of palaeoatmospheric CO2 levels for the Cenezoic, Mesozoic, and Paleozoic eras. In particular, the cuticles of cycads, ginkgoes, conifers, and pteridosperms have frequently been used for this purpose. Within this study, the CO2 concentration of the early Late Permian was reconstructed by performing stomatal frequency analysis of these Comia fossils, suggesting a maximum palaeoatmospheric CO2 concentration of 1929.5 ppmv, consistent with the estimates obtained using GEOCARB III, and a minimum of 1157.8 ppmv, consistent with the estimates obtained using GEOCARB II.

关键词： Late Permian Comia cuticle stomatal parameter palaeoatmospheric CO2