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地震正演模型应用(Ⅱ):用地震正演叠前炮集记录模拟方法定量解释薄砂岩的各向异性(英文)

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石油勘探与开发 2005年第6期32卷 87-90页

作者： ben f mclean 戴金星姚蓬昌中国石油勘探开发研究院 finlay Geoscience

叠前地震正演模拟可以获得比叠后正演更多的有用信息,例如能够用于含有各向异性特征的精细速度建模的信息。塔里木盆地下石炭统存在砂泥岩互层,偶见石膏、砾岩和煤层。砂泥岩薄互层中的速度差异可能导致各向异性,但是利用常规的地震方... 详细信息

叠前地震正演模拟可以获得比叠后正演更多的有用信息,例如能够用于含有各向异性特征的精细速度建模的信息。塔里木盆地下石炭统存在砂泥岩互层,偶见石膏、砾岩和煤层。砂泥岩薄互层中的速度差异可能导致各向异性,但是利用常规的地震方法很难识别和定量描述各向异性。由叠前各向同性正演获得的炮集,证明砂泥岩中存在各向异性,通过迭代生成的理论合成炮集与实际原始炮集相对比,可以定量描述各向异性,结果证明在该区砂泥岩层存在5%的横向各向同性,其高速传播方向为水平面。

关键词：塔里木盆地砂泥岩段地震模拟各向异性横向各向同性

Multicomponent polymerization of elemental sulfur,difluoromethylene phosphobetaine and aryl silyl ethers toward aromatic poly(O,O′-monothiocarbonate)s

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Science China Chemistry 2025年

作者： Yongjiang Yu Rongrong Hu ben Zhong Tang State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates South China University of Technology School of Science and Engineering Shenzhen Institute of Aggregate Science and Technology The Chinese University of Hong Kong AIE Institute

Polythiocarbonates with similar structures to polycarbonates, have emerged as a group of promising sulfur-containing polymers with a range of practical applications, taking advantages of their excellent optical properties, good thermal stability and filmforming ability, and so on. However, the synthesis of polythiocarbonates generally suffered from mixed isomeric structures of repeating units, and hazardous sulfur-containing reagents. In this work, an efficient multicomponent reaction of elemental sulfur,difluoromethylene phosphobetaine（PDfA）, and aryl silyl ethers was designed with the assistance of organic base 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene（MTBD） to produce 12 kinds of O,O′-monothiocarbonate compounds in up to 93% yields,taking advantages of the unique chemical property of difluorocarbene, and the deprotection of silyl group by f-generated from PDfA. Most importantly, the MTBD-assisted multicomponent polymerization of bis（aryl silyl ether）s, elemental sulfur, and PDfA was developed, affording 12 kinds of poly（O,O′-monothiocarbonate）s with well-defined structures, high Mws of up to16900 g/mol and high yields（up to 99%）. These poly（O,O′-monothiocarbonate）s possessed good film-forming properties and thermal stability, high light refractive indices and transmittance. The facile synthesis of these polymonothiocarbonates might pave the way for the development of promising sulfur-containing polymer materials.

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Use of Solid State Carbothermic Reduction in Production of Transition Metals and Their Carbides

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Journal of Iron and Steel Research International 2000年第2期7卷 14-22页

作者： YANG Yin-dong SOMMERVILLE I D JOHNSTON R f mclean A University of Toronto LaTrobe University

The use of solid state carbothermic reduction as a precursor to the smelting of transition metal ores was examined . The advantages of the introduction of a prereduction stage include enabling the more efficient use of fines and the achievement of higher energy efficiencies. A solid state reduction using carbon as the reductant offers a simpler alternative for their treatment. Subsequent treatment of the reduced material could include intensive bath smelting to produce ferroalloys or, in some case, solid state separation of the transition metal carbide where this has commercial significance.

关键词： solid state carbothermic reduction transition metals carbide

Development of Mathematical Model of Slag flow field and Temperature field in ESR System

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Journal of Iron and Steel Research International 2000年第2期7卷 27-31页

作者： YANG Yin-dong SOMMERVILLE I D JOHNSTON R f mclean A University of Toronto LaTrobe University

The heat transfer phenomena and driving forces of slag bath flow in ESR process were analyzed, and the mathematical models in ESR system were reviewed and evaluated. The electromagnetic force is the main driving force for the flow formation in the ESR slag pool, and the temperature difference in the pool creates a convective flow in the system. The shape of the electrode tip has an effect on electromagnetic field distribution in slag pool, thus affects the flow pattern. finally an improved mathematical model of slag pool flow was proposed.

关键词： ESR electromagnetic force buoyancy force flow field temperature field mathematical model

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近地表地震散射波分离方法

石油勘探与开发 2014年第6期41卷 705-711页

作者：徐基祥 mclean B f 宋雪娟中国石油勘探开发研究院北京勘源科技有限公司

针对常规去噪处理无法压制近地表散射波的问题,通过分析近地表地震散射波特征,利用地震干涉测量理论,实现近地表地震散射波分离。山地地震资料信噪比普遍较低,有效波能量弱,近地表散射波能量强,地震数据处理中必须分离近地表散射波,提... 详细信息

针对常规去噪处理无法压制近地表散射波的问题,通过分析近地表地震散射波特征,利用地震干涉测量理论,实现近地表地震散射波分离。山地地震资料信噪比普遍较低,有效波能量弱,近地表散射波能量强,地震数据处理中必须分离近地表散射波,提高地震资料信噪比。相邻炮集上的近地表地震散射波同相轴相互平行,根据近地表散射波运动学规律,通过地震干涉测量,消除地震波传播过程中相同路径的影响,近地表散射波得到相干加强,进而从原始地震记录中将其分离。以中国西部山地地震资料为例,通过直达波场与全波场地震干涉测量,加强散射波能量,进行散射波分离,处理后的地震资料基本消除了近地表散射波,验证了近地表地震散射波分离方法的有效性和可行性。

关键词：山地地震勘探近地表地震散射波散射波分离地震干涉测量

Normal Crossings Singularities for Symplectic Topology:Structures

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Acta Mathematica Sinica,English Series 2024年第1期40卷 107-160页

作者： Mohammad fARAJZADEH-TEHRANI Mark mclean Aleksey ZINGER The University of Iowa MacLean HallIowa CityIA 52241 Department of Mathematics Stony Brook UniversityStony BrookNY 11794

Our previous papers introduce topological notions of normal crossings symplectic divisor and variety,show that they are equivalent,in a suitable sense,to the corresponding geometric notions,and establish a topological smoothability criterion for normal crossings symplectic *** present paper constructs a blowup,a complex line bundle,and a logarithmic tangent bundle naturally associated with a normal crossings symplectic divisor and determines the Chern class of the last *** structures have applications in constructions and analysis of various moduli *** a corollary of the Chern class formula for the logarithmic tangent bundle,we refine Aluffi’s formula for the Chern class of the tangent bundle of the blowup at a complete intersection to account for the torsion and extend it to the blowup at the deepest stratum of an arbitrary normal crossings divisor.

关键词： Normal crossings divisor Chern class Logarithmic tangent bundle

Dephosphorization Thermodynamics of Crude Steel Using CaO-Based flux

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Journal of Iron and Steel Research International 2003年第3期10卷 10-15页

作者： YANG Yin-dong McKague A R mclean A Sommerville I D University of Toronto

The experiments were carried out at 1 175-1 450 ℃ to study the phosphorus distribution ratio between molten Ca O-based slags and carbon saturated hot metal. The phosphate capacity of the slags and the activity coefficient of PO2. 5were calculated from the phosphorus distribution ratio. The effect of addition of Ca f2 and / or Ca Cl2 on the thermodynamic properties of slags was discussed. The correlation of optical basicity with phosphate capacity of slags was studied,and the dephosphorization ability of Ca O-based fluxes with various additives was compared with the results from different studies.

关键词： phosphorus activity coefficient phosphate capacity optical basicity lime-based flux clean steel

Symbolic generation of the kinematics of multibody systems in EasyDyn: from MuPAD to Xcas/Giac

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Theoretical & Applied Mechanics Letters 2013年第1期3卷 89-94页

作者： Olivier Verlinden Lassaad ben fkih Georges Kouroussis Department of Theoretical Mechanics Dynamics and Vibrations University of Mons

In the EasyDyn multibody open source project, computer algebra has been used from the beginning to generate the expressions of velocities and accelerations of the bodies, by symbolic differentiation of their position. Originally, the MuPAD computer algebra system had been retained because it was freely available for non commercial purposes and showed very good technical ***, MuPAD is nowadays only available through commercial channels and needs to be replaced to keep EasyDyn publicly available. This paper presents why Xcas/Giac is finally selected,among other long-term promising projects like Axiom, Maxima, Sage or Yacas. Among the choice criteria, the accessibility, the portability, the ease of use, the automatic export to C language, and the similarity with the -MuPAD language are all considered. The performances of the MuPAD and Xcas/Giac implementations are also compared on some examples.C 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi：10.1063/2.13013012]

关键词： symbolic multibody systems kinematics computer algebra system open source

Unraveling the morphological patterns of a subantarctic eelpout:a geometric morphometric approach

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Integrative Zoology 2023年第2期18卷 372-384页

作者： fernanda S.ORREGO Mathias HÜNE Hugo A.benÍTEZ Mauricio f.LANDAETA Laboratorio de Ictiología e Interacciones Biofísicas(LABITI) Instituto de BiologíaFacultad de CienciasUniversidad de ValparaísoValparaísoChile Centro de Investigación para la Conservación de los Ecosistemas Australes(ICEA) Punta ArenasChile Laboratorio de Ecología y Morfometría Evolutiva Centro de Investigación de Estudios Avanzados del MauleUniversidad Católica del MauleTalcaChile Centro de Observación Marino para Estudios de Riesgos del Ambiente Costero(COSTA-R) Universidad de ValparaísoViña del MarChile Millennium Nucleus for Ecology and Conservation of Temperate Mesophotic Reef Ecosystems(NUTME) Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems(BASE) SantiagoChile

Phenotypic variation in organisms depends on the genotype and the environmental constraints of the habitat that they ***,for marine species inhabiting contrasting aquatic conditions,it is expected toﬁnd covari-ation between the shape and its spatial *** studied the morphology of the head and cephalic sensory canals of the eelpout Austrolycus depressiceps(4.5–22.5 cm TL)across its latitudinal distribution in South Paciﬁc(45°S–55°S).Geometric morphometric analyses show that the shape varied from individuals with larger snout and an extended suborbital canal to individuals with shorter snouts and frontally compressed suborbital *** was size variation across the sampled populations,but that size does not have a clear latitudinal *** 8%of the shape variation relates to this size variation(allometry),represented by a decrease in the relative size of the eye,and a depression of the posterior margin of the *** were spatial differences in the shape of the head,but these differences were probably caused by allometric ***,2 of the canals of the cephalic lateralis pores and the head shape showed modularity in its *** study shows that the morphology of marineﬁsh with a shallow distribution varies across distances of hundreds of kilometers(i.e.,phenotypic modulation).

关键词： Austrolycus depressiceps geometric morphometrics morphology phenotype spatial distribution