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Carbonate metasomatism in the lithospheric mantle: Implications for cratonic destruction in North China

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Science China Earth Sciences 2018年第6期61卷 711-729页

作者： Keqing ZONG yongsheng liu State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of GeosciencesWuhan

The activity of melts and fluids may have played a key role in inducing the destruction of the eastern North China Craton in the early Cretaceous. Carbonate melts are important agents in mantle metasomatism and can significantly modify the physical and chemical properties of the subcontinental lithospheric mantle. Carbonate metasomatism can be identified by specific geochemical indices in clinopyroxene, such as high Ca/Al and low Ti/Eu ratios. This study presents the spatial and temporal variations of carbonate metasomatism in the lithospheric mantle beneath the eastern North China Craton. Three types of carbonate metasomatism are classified based on the geochemical compositions of clinopyroxene in mantle peridotites. Clinopyroxene formed by Type 1 carbonate metasomatism is characterized by very high Ca/Al ratios(15–70) and^(87)Sr/^(86)Sr ratios(0.706–0.713). Clinopyroxene derived from Type 2 carbonate metasomatism shows relatively high Ca/Al ratios(5–18) and^(87)Sr/^(86)Sr ratios(0.703–0.706). However, clinopyroxene resulting from Type 3 carbonate metasomatism has low Ca/Al ratios(5–9) and^(87)Sr/^(86)Sr ratios(0.702–0.704). Deep(garnet-bearing) and shallow(spinel-bearing) lithospheric mantle beneath the Sulu orogen and surrounding areas in the eastern North China Craton were affected by intense Type 1 carbonate metasomatism before the late Triassic. The deep subduction of the South China Block with its accompanying carbonate sediments was the trigger for Type 1 carbonate metasomatism, which reduced strength of the lithospheric mantle and provided a prerequisite for the destruction of the eastern North China Craton in the early Cretaceous. After the destruction of the eastern North China Craton, the ancient relict lithospheric mantle, represented by spinel harzburgite xenoliths hosted in the late Cretaceous to Cenozoic basalts,only recorded Type 2 carbonate metasomatism. This implies that the lithospheric mantle experienced the intense Type 1 carbonate metasomatism

关键词： Cratonic destruction North China Carbonate metasomatism Ca/Al in clinopyroxene Lithospheric mantle

Recent Progress of Layered Perovskite Solar Cells Incorporating Aromatic Spacers

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Nano-Micro Letters 2023年第10期15卷 163-181页

作者： Yuping Gao Xiyue Dong yongsheng liu The Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer Materials Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071People’s Republic of China Renewable Energy Conversion and Storage Center(RECAST) Nankai UniversityTianjin 300071People’s Republic of China

Layered two dimensional(2D) or quasi-2D perovskites are emerging photovoltaic materials due to their superior environment and structure stability in comparison with their 3D counterparts. The typical 2D perovskites can be obtained by cutting 3D perovskites along orientation by incorporation of bulky organic spacers, which play a key role in the performance of 2D perovskite solar cells(PSCs). Compared with aliphatic spacers, aromatic spacers with high dielectric constant have the potential to decrease the dielectric and quantum confinement effect of 2D perovskites, promote efficient charge transport and reduce the exciton binding energy, all of which are beneficial for the photovoltaic performance of 2D PSCs. In this review, we aim to provide useful guidelines for the design of aromatic spacers for 2D perovskites. We systematically reviewed the recent progress of aromatic spacers used in 2D PSCs. Finally, we propose the possible design strategies for aromatic spacers that may lead to more efficient and stable 2D PSCs.

关键词： Layered perovskite solar cells Aromatic spacers Quantum and dielectric confinement effects Charge transport Efficiency and stability

Surface in-situ reconstruction boosting the efficiency of inorganic perovskite solar cells

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Science China Chemistry 2023年第8期66卷 2153-2154页

作者： Xiyue Dong yongsheng liu Institute of Polymer Chemistry College of ChemistryNankai UniversityTianjin300071China

This article highlights recent advancements in inorganic perovskite solar cells(PSCs)published in Nature Energy by You et al.[1].They developed an innovative surface in-situ reconstruction(SISR)method for inorganic perovskites by directly spin-coating the fluoride salts in isopropanol(IPA)solution onto the inorganic perovskite film followed by thermal annealing.

关键词： inorganic perovskite boosting

Recent Progress of Inorganic Hole-Transport Materials for Perovskite Solar Cells

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Chinese Journal of Chemistry 2023年第23期41卷 3373-3387页

作者： Rui Wang Xiyue Dong yongsheng liu The Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer Materials Institute of Polymer ChemistryCollege of Chemistry and Renewable Energy Conversion and Storage Center (RECAST)Nankai UniversityTianjin300071 China

Perovskite solar cells (PSCs) have achieved significant progress in the past decade and a certified power conversion efficiency (PCE) of 26.0% has been *** widely used organic hole transport materials (HTMs) in PSCs are typically sensitive to the moisture environment and continuous light *** contrast,the inorganic HTMs benefiting from their outstanding merits,such as excellent environmental stability,are considered as alternatives and have attracted much attention in *** this review,we provide a comprehensive summary of the fundamental properties and recent progress of inorganic HTMs in n-i-p and p-i-n structured ***,we emphasize the importance of inorganic HTMs in the development of highly efficient and stable PSCs.

关键词： Perovskite solar cells Inorganic nanomaterials Hole transport layers Crystals Molecular modification Photovoltaic properties

Synthesis and properties of copolymers based on 5,6-dinitrobenzothiadiazole with low band gap and broad absorption spectra

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Science China Chemistry 2011年第4期54卷 617-624页

作者： WANG Fei liu yongsheng WAN XiangJian ZHOU JiaoYan CHEN yongsheng Key Laboratory for Functional Polymer Materials and Centre for Nanoscale Science and Technology Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China

One polythiophene derivative PT3T and two low band gap copolymers,PBTT-T3T and PBTT,with different ratios of 5,6-dini-trobenzothiadiazole as the acceptor unit in the polymer backbone have been synthesized by Pd-catalyzed Stille-coupling *** stability,X-ray diffraction analyses,UV-vis absorption spectra,photoluminescence spectra and electrochemical properties of the copolymers were *** band gap estimated from UV-vis-NIR spectra of the copolymers films varied from 1.39 to 1.94 *** these copolymers,the films of PBTT-T3T and PBTT,which contain the 5,6-dinitrobenzothiadiazole unit,cover a broad wavelength range in the visible and near-infrared region from 400 to 1000 nm with the maximal peak absorption around 700 nm,which is exactly matched with the maximum in the photon flux of the sun.

关键词： copolymer broad absorption low band gap charge transfer

室温磁致冷材料Mn_(5)Ge_(2.7)Zn_(0.3)的相变、磁热效应和临界行为

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上海交通大学学报 2025年第1期59卷 131-138页

作者：许童杰刘振华金怀宇刘结蒋秀丽李哲刘永生上海电力大学数理学院上海200090 曲靖师范学院磁性材料及器件研究中心云南曲靖655011

通过电弧熔炼法成功制备了Mn_(5)Ge_(2.7)Zn_(0.3)合金,并对其相变、磁热效应和临界行为等进行研究.利用热磁曲线确定了样品的居里温度为297.2 K,等温磁化曲线发现样品没有热滞,通过M2-H/M曲线和Banerjee准则证实样品经历了二级相变,进... 详细信息

通过电弧熔炼法成功制备了Mn_(5)Ge_(2.7)Zn_(0.3)合金,并对其相变、磁热效应和临界行为等进行研究.利用热磁曲线确定了样品的居里温度为297.2 K,等温磁化曲线发现样品没有热滞,通过M2-H/M曲线和Banerjee准则证实样品经历了二级相变,进一步根据Maxwell方程计算样品的等温熵变,场-熵的幂律关系和归一化曲线也验证了二级相变.利用modified Arrott plot(MAP)法、Kouvel-Fisher(KF)法和等温磁化(CI)法求解临界指数,并用Widom标度定律和标度方程验证了临界指数的准确性.最后利用Arrott-Noaks方程对样品的临界行为进一步分析,归一化斜率和磁相互作用距离的分析证实了样品内部磁相互作用的复杂性.

关键词： Mn_(5)Ge_(3)基合金二级相变磁热效应临界行为相互作用

Fabrication and characterization of SiO_(2(f))/Si)_3N_4 composites

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Journal of University of Science and Technology Beijing 2007年第5期14卷 454-459页

作者： yongsheng liu Laifei Cheng Litong Zhang Yongdong Xu Yi liu National Key Laboratory of Thermostructure Composite Materials Northwestern Polytechnical University Xi＇an 710072 China

A silicon dioxide fiber-reinforced silicon nitride matrix （SiOJSi3N4） composite used for radomes was prepared by chemical vapor infiltration （CVI） process using the SiCl4-NH3-H2 system. The effects of the process conditions, including infiltration temperature, infiltration time, and gas flux were investigated. The energy dispersion spectra （EDS） result showed that the main elements of this composite contained Si, N, and O. The X-ray diffraction （XRD） results indicated that phases of the composite before and after treatment at 1350℃ were all amorphous. A little fiber pull-out was observed on the cross section of the composite by scan electron microscope （SEM）. As a result, the composite exhibited good thermal stability, but an appropriate interface was necessary between the fiber and the matrix.

关键词： SiO2/ Si3N4 composite fabrication characterization chemical vapor infiltration

Proportional Limit Stress and Residual Thermal Stress of 3D SiC/SiC Composite

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Journal of Materials Science & Technology 2014年第10期30卷 959-964页

作者： Shanhua liu Litong Zhang Xiaowei Yin yongsheng liu Laifei Cheng Science and Technology on Thermal Structural Composite Materials Laboratory School of Materials Science and EngineeringNorthwestern Polytechnical University

Proportional limit stress （PLS） and residual thermal stresses （RTS） of 3D SiC/SiC composite were investigated. PLS was obtained by four different methods from the monotonic stress-strain response curve to get a convincing value. RTS in the SiC matrix was quantified by solving the geometric intersection point of the regression lines of hysteresis loops from the periodical loading-unloading-reloading cycle test curve. Classical ACK model and analytical formulas were used to analytically calculate the PLS and RTS of 3D SiC/ SiC composite. Good agreement between the experimental results and the analytical calculation was observed. And relationship between the PLS and the RTS of 3D SiC/SiC was discussed.

关键词： Proportional limit stress Residual thermal stresses Mechanical properties Ceramic matrix composites

Recent progress of dopant-free organic hole-transporting materials in perovskite solar cells

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Journal of Semiconductors 2017年第1期38卷 28-37页

作者： Dongxue liu yongsheng liu Key Laboratory of Functional Polymer Materials Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China

Organic-inorganic hybrid perovskite solar cells have undergone especially intense research and transformation over the past seven years due to their enormous progress in conversion *** this perspective,we review the latest developments of conventional perovskite solar cells with a main focus on dopant-free organic hole transporting materials（HTMs）.Regarding the rapid progress of perovskite solar cells,stability of devices using dopant-free HTMs are also discussed to help readers understand the challenges and opportunities in high performance and stable perovskite solar cells.

关键词： hole transport materials perovskite photovoltaic charger transport stability