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Structural architecture of Neoproterozoic rifting depression groups in the Tarim Basin and their formation dynamics

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Science China Earth Sciences 2019年第3期62卷 529-549页

作者： Bizhu HE Cunli JIAO Taizhu HUANG Xingui ZHOU Zhihui CAI Zicheng CAO Zhongzheng JIANG Junwen CUI Zhuoyin YU Weiwei CHEN Ruohan LIU Xiaorui YUN Guangming HAO Institute of Geology Chinese Academy of Geological Sciences Exploration and Production Research Institute of SINOPEC Institute of Northwestern Petroleum Subsidiary of SINOPEC Oil and Gas Investigation Centre of China Geological Survey

The Tarim Basin is the largest, oil-bearing, superimposed basin in the northwest of China. The evolution and tectonic properties of the initial Tarim Basin have been hotly disputed and remain enigmatic. The Neoproterozoic basin is covered by a vast desert and a huge-thickness of sedimentary strata, has experienced multiple tectonic movements, had a low signal to noise ratios(SNRs) of deep seismic reflection data, all of which have posed critical obstacles to research. We analysed four field outcrops, 18 wells distributed throughout the basin, 27 reprocessed seismic reflection profiles with higher SNRs across the basin and many ancillary local 2D and 3D profiles and aeromagnetic data. We found about 20 normal fault-controlled rifting depressions of the Cryogenian and Ediacaran scattered throughout the basin, which developed on the Precambrian metamorphic and crystalline basement. The structural framework is clearly different from that of the overlying Phanerozoic. The rifting depressions consist of mainly half grabens, symmetrical troughs and horst-grabens. From the northeast to southwest of the basin,they are divided into three rifting depression groups with the WNW, ENE, and NW-trends that are mainly controlled by normal faults. The maximum thicknesses of the strata are up to 4100 m. From the Cryogenian to Ediacaran, most of the main inherited faults to active and eventually ceased at the end of the Ediacaran or Early Cambrian, while subsidence centres appeared and migrated eastward along the faults. They revealed that the different parts of the Tarim continental block were in NNE-SSWoriented and NNW-SSE-oriented extensional paleo-stress fields(relative to the present) during the Neoproterozoic, and were accompanied by clockwise shearing. According to the analysis of the activities of syn-sedimentary faults, filling sediments,magmatic events, and coordination with aeromagnetic anomalies, the tectonic properties of the fault depressions are different and are primari

关键词： Rifting depression groups Normal faults Extensional and clockwise shearing Cryogenian and Ediacaran Continental rift and intra-continental fault-controlled basin Tarim Basin

Transmission Eigenvalues and the Riemann Zeta Function in Scattering Theory for Automorphic Forms on Fuchsian groups of Type Ⅰ

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Acta Mathematica Sinica,English Series 2019年第6期35卷 987-1010页

作者： Fioralba CAKONI Sagun CHANILLO Department of Mathematics Rutgers University

We introduce the concept of transmission eigenvalues in scattering theory for automorphic forms on fundamental domains generated by discrete groups acting on the hyperbolic upper half complex plane. In particular, we consider Fuchsian groups of Type Ⅰ. Transmission eigenvalues are related to those eigen-parameters for which one can send an incident wave that produces no scattering. The notion of transmission eigenvalues, or non-scattering energies, is well studied in the Euclidean geometry, where in some cases these eigenvalues appear as zeros of the scattering matrix. As opposed to scattering poles,in hyperbolic geometry such a connection between zeros of the scattering matrix and non-scattering energies is not studied, and the goal of this paper is to do just this for particular arithmetic *** such groups, using existing deep results from analytic number theory, we reveal that the zeros of the scattering matrix, consequently non-scattering energies, are directly expressed in terms of the zeros of the Riemann zeta function. Weyl's asymptotic laws are provided for the eigenvalues in those cases along with estimates on their location in the complex plane.

关键词： Transmission eigenvalues Fuchsian groups Riemann zeta function scattering theory

Strong Embeddability for groups Acting on Metric Spaces

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Chinese Annals of Mathematics,Series B 2019年第2期40卷 199-212页

作者： Jun XIA Xianjin WANG College of Mathematics and Statistics Chongqing University

The strong embeddability is a notion of metric geometry, which is an intermediate property lying between coarse embeddability and property A. In this paper, the permanence properties of strong embeddability for groups acting on metric spaces are studied. The authors show that a finitely generated group acting on a finitely asymptotic dimension metric space by isometries whose K-stabilizers are strongly embeddable is strongly embeddable. Moreover, they prove that the fundamental group of a graph of groups with strongly embeddable vertex groups is also strongly embeddable.

关键词： Strong embeddability groups action Graph of groups Relative hyperbolic groups

Effect of Graphene Surface Functional groups on the Mechanical Property of PMMA Microcellular Composite Foams

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Journal of Wuhan University of Technology(Materials Science) 2019年第3期34卷 717-722页

作者： LI Meijuan SHEN Qiang School of Chemistry Chemical Engineering and Life SciencesWuhan University of TechnologyWuhan430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

The functional groups on graphene sheets surface affect their dispersion and interfacial adhesion in polymer matrix. We compared the mechanical property of polymethymethacrylate（PMMA） microcellular foams reinforced with graphene oxide（GO） and reduced graphene oxide（RGO） to investigate this influence of functional groups. RGO sheets were fabricated by solvent thermal reduction in DMF medium. UV-Vis, FT-IR and XPS analyses indicate the difference of oxygen-containing groups on GO and RGO sheets surface. The observation of SEM illustrates that the addition of a smaller number of GO or RGO sheets causes a fine cellular structure of PMMA foams with a higher cell density(about 1011 cells/cm3) and smaller cell sizes（about 1-2 μm） owing to their remarkable heterogeneous nucleation effect. Compared to GO reinforced foams, the RGO/PMMA foams own lower cell density and bigger cell size in their microstructure, and their compressive strength is lower even when the reinforcement contents are the same and the foam bulk density is higher. These results indicate that the oxygen-containing groups on GO sheets’ surface are beneficial to adhere CO2 to realize a larger nucleation rate, and their strong interaction with PMMA matrix improves the mechanical property of PMMA foams.

关键词： graphene surface functional groups PMMA microcellular composite foams mechanical property

Attaching CF_(3) groups to organic molecules using trifluoroacetates via ion-shielding photoelectrocatalysis

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Science China Chemistry 2024年第11期67卷 3495-3497页

作者： Paula Visiedo-Jiménez Francisco Juliá-Hernández Departamento de Química Inorgánica Facultad de QuímicaUniversidad de MurciaCampus de EspinardoMurcia 30100Spain

Fluorinated molecules play a protagonist role in pharmaceuticals, agrochemicals, and materials. The incorporation of fluoroalkyl groups into organic compounds provides them with unique chemical properties that are key... 详细信息

关键词： materials groups compounds

Littlewood–Paley Operators on Spaces with Variable Exponent on Homogeneous groups

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Acta Mathematica Sinica,English Series 2020年第5期36卷 535-558页

作者： Dong Li LIU Ji Man ZHAO Key Laboratory of Mathematics and Complex Systems Ministry of Education Institution of Mathematics and Mathematical Education School of Mathematical SciencesBeijing Normal UniversityBeijing 100875P.R.China

In this paper,on homogeneous groups,we study the Littlewood–Paley operators in variable exponent ***,we prove that the weighted Littlewood–Paley operators are controlled by the weighted Hardy–Littlewood maximal function,and obtain the vector-valued inequalities of the Littlewood–Paley operators,including the Lusin function,Littlewood–Paley g function and gλ* ***,we prove the boundedness of multilinear Littlewood–Paley gψ,λ* function.

关键词： Littlewood–Paley operators variable Lebesgue spaces homogeneous groups

Evolution of Galaxy Types and HI Gas in Hickson Compact groups

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Research in Astronomy and Astrophysics 2022年第10期22卷 189-201页

作者： Yao Liu Ming Zhu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST NAOCChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Compact groups have high galaxy densities and low velocity dispersions,and their group members have experienced numerous and frequent interactions during their *** provide a unique environment to study the evolution of *** examined the galaxies types and H I contents in groups to make a study on the galaxy evolution in compact *** used the group crossing time as an age indicator for galaxy *** sample is derived from the Hickson Compact Group *** obtained group morphology data from the Hyper-Leda database and the IR classification based on Wide-Field Infrared Survey Explorer fluxes from Zucker et *** cross-matching the latest released ALFALFA 100%H I source catalog with supplement by data found in literature,we obtained 40 galaxy groups with H I data *** confirmed that the weak correlation between H I mass fraction and group crossing time found by Ai&Zhu in SDSS groups also exists in compact *** also found that the group spiral galaxy fraction is correlated with the group crossing time,but the actively star-forming galaxy fraction is not correlated with the group crossing *** results seem to fit with the hypothesis that the sequential acquisition of neighbors from surrounding larger-scale structures has affected the morphology transition and star formation efficiency in compact groups.

关键词： galaxies evolution-galaxies groups general-galaxies ISM

Semilinear automorphisms of classical groups and quivers

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Science China Mathematics 2019年第11期62卷 2355-2370页

作者： Jinwei Yang Zhiwei Yun Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAB T6G 2G1Canada Department of Mathematics Massachusetts Institute of TechnologyCambridgeMA 02139USA

For a classical group G over a field F together with a finite-order automorphism θ that acts compatibly on F, we describe the fixed point subgroup of θ on G and the eigenspaces of θ on the Lie algebra g in terms of cyclic quivers with involution. More precise classification is given when g is a loop Lie algebra, i.e.,when F = C((t)).

关键词： semilinear automorphisms classical groups quiver

The Subgroups of Finite Metacyclic groups

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Chinese Annals of Mathematics,Series B 2020年第2期41卷 241-266页

作者： Xu YANG School of Mathematical Sciences Fudan UniversityShanghai 200433China

In this paper, the author characterizes the subgroups of a finite metacyclic group K by building a one to one correspondence between certain 3-tuples(k, l, β) ∈ N3 and all the subgroups of K. The results are applied to compute some subgroups of K as well as to study the structure and the number of p-subgroups of K, where p is a fixed prime number. In addition, the author gets a factorization of K, and then studies the metacyclic p-groups, gives a different classification, and describes the characteristic subgroups of a given metacyclic p-group when p ≥ 3. A "reciprocity" relation on enumeration of subgroups of a metacyclic group is also given.

关键词： Metacyclic groups Subgroups Metacyclic p-groups Characteristic subgroups