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Trace element compositions of pyrite and stibnite:implications for the genesis of antimony mineralization in the Yangla Cu skarn deposit,Northwestern Yunnan,china

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Acta Geochimica 2024年第3期43卷 535-554页

作者： ping Pan Xinfu Wang Bo Li guo tang Zuopeng Xiang Faculty of Land and Resource Engineering Kunming University of Science and TechnologyKunming 650093China Kunming Metallurgy College Kunming 650033China school of Earth Science Yunnan UniversityKunming 650500China Kunming Prospecting Design Institute of china Nonferrous Metals Industry Co. LtdKunming 650051China

The Yangla Cu skarn deposit is located in the central part of the Jinshajiang Suture Zone,southwest china,with a total reserve of 150 Mt Cu@1.03..The newly discovered antimony orebodies at the depth of Yangla are strictly controlled by the stratum,structure,and lithology,which are lenticular and vein-like within the marble fracture zone,which can provide a window into multistage miner-alization and ore genesis at *** can be divided into three types,Cu–Pb–Zn(skarn)pyrite,galena,and sphalerite,Cu(porphyry)chalcopyrite and pyrite,and Sb(hydrothermal)stibnite and *** mineral assem-blages were stibnite+pyrite+calcite+quartz±minor scheelite in antimony *** study presents quantitative measurements of the trace element compositions of pyrite and stibnite from the Yangla antimony *** of pyrite with electron probe microanalysis(EPMA)showed enrichment in Co,Ni,Sb,As,and Mo,and deficit in its S and Fe contents when compared to the stoichiometric con-centrations of S and Fe in *** Sb-related pyrite may belong to sedimentary-reworked genesis and may be modi-fied by hydrothermalfluids,thereby presenting a certain dif-ference(i.e.,crystal morphology,texture,and chemical com-position)compared to the skarn and porphyry Cu-related pyrite in the Yangla Cu skarn *** of stibnite with EPMA and inductively coupled plasma-mass spectrom-etry showed enrichment in As,Pb,Sn,Pb,Cu,and Zn,and presented much higher Sb contents and slightly lower S con-tents when compared to the stoichiometric concentrations of Sb and S in *** analysis of the stibnite trace elements showed correlations for the elemental pairs Cu–Pb,As–Sb,and Sn–Pb,and the coupled substitution equations Sb^(3.)↔Cu^(+)+Pb^(2+),Sb^(3.)↔As^(3.),and Sn^(2+)↔Pb^(2+)may be the major factors governed the incorporating Cu,Pb,As and Sn within the ***,this study preliminary shows that the antimony mineralization may belong to a car-bonate replacement h

关键词： Trace elements Pyrite Stibnite Substitution mechanisms Antimony mineralization Yangla Cu skarn deposit

Three types of promising functional building units for designing metal halide nonlinear optical crystals

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Chinese Journal of Structural Chemistry 2024年第6期43卷 8-11页

作者： Jiajing Wu Ru-Ling tang Sheng-ping guo school of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou225002PR China Yunnan Key Laboratory of Electromagnetic Materials and Devices National Center for International Research on Photoelectric and Energy MaterialsSchool of Material and EnergyYunnan UniversityKunming650000PR China

Nonlinear optical(NLO)crystal materials greatly extend the tunable range of laser by frequency conversion,which promotes the rapid development of laser technology and plays an important role in many civil and military *** excellent and famous NLO crystals from the ultraviolet(UV)to visible to near infrared(NIR)regions have been developed,such as borates(KBe_(2)BO_(3.F_(2),β-BaB_(2)O_(4.),phosphates(KH_(2)PO_(4.,KTiOPO_(4.),chalcogenides(AgGaS_(2),AgGaSe_(2))and so on[1,2].

关键词： optical tunable designing

INFINITE ELEMENT METHOD FOR THE EXTERIOR PROBLEMS OF THE HELMHOLTZ EQUATIONS

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Journal of Computational Mathematics 2000年第6期18卷 657-672页

作者： Lung-an Ying (school of mathematical sciences, Peking {3., {4. 100871, china) 北京大学北京 100871

There are two cases of the exterior problems of the Helmholtz equation. If λ ≥ 0 the bilinear form is coercive, and if λ < 0 it is the scattering problem. We give a new approach of the infinite element method, which enables us to solve these exterior problems as well as corner problems. A numerical example of the scattering problem is given. [ABSTRACT FROM AUTHOR]

关键词： Helmholtz equation exterior problem infinite element method

Twistor bundle theory and its application

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Science china Mathematics 2004年第4期47卷 605-616页

作者： PENG Chia-Kuei & tang ZizhouDepartment of Mathematics, graduate school of Chinese Academy of {3., {4. 10003., china Department of mathematical {3., Tsinghua university, {4. 100084. china 1. Department of Mathematics Graduate School of Chinese Academy of Sciences 100039 Beijing China 2. Department of mathematical sciences Tsinghua University 100084 Beijing China

Over an oriented even dimensional Riemannian manifold(M 2m ,ds2 ), in terms of the Levi-Civita connection form Ω and the canonical form Θ on the bundle of positive orthonormal frames, we give a detailed description of the twistor bundle Гm = SO(2m)/U(m)? J +(@#@ M,ds2 ) →M. The integrability on an almost complex structureJ compatible with the metric and the orientation, is shown to be equivalent to the fact that the corresponding cross section of the twistor bundle is holomorphic with respect toJ and the canonical almost complex structureJ 1 onJ +(M,ds2 ), by using moving frame theory. Moreover, for various metrics and a fixed orientation onM, a canonical bundle isomorphism is established. As a consequence, we generalize a celebrated theorem of LeBrun.

关键词： almost complex structure, integrability, twistor bundle.

Emerging memristors and applications in reservoir computing

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Frontiers of physics 2024年第1期19卷 219-239页

作者： Hao Chen Xin-Gui tang Zhihao Shen Wen-Tao guo Qi-Jun Sun Zhenhua tang Yan-{3. Jiang school of Physics and Optoelectronic Engineering Guangdong University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou 510006China

Recently, with the emergence of ChatGPT, the field of artificial intelligence has garnered widespread attention from various sectors of society. Reservoir Computing (RC) is a neuromorphic computing algorithm used to analyze time-series data. Unlike traditional artificial neural networks that require the weight values of all nodes in the trained network, RC only needs to train the readout layer. This makes the training process faster and more efficient, and it has been used in various applications, including speech recognition, image classification, and control systems. Its flexibility and efficiency make it a popular choice for processing large amounts of complex data. A recent research trend is to develop physical RC, which utilizes the nonlinear dynamic and short-term memory properties of physical systems (photonic modules, spintronic devices, memristors, etc.) to construct a fixed random neural network structure for processing input data to reduce computing time and energy. In this paper, we introduced the recent development of memristors and demonstrated the remarkable data processing capability of RC systems based on memristors. Not only do they possess excellent data processing ability comparable to digital RC systems, but they also have lower energy consumption and greater robustness. Finally, we discussed the development prospects and challenges faced by memristors-based RC systems.

关键词： reservoir computing memristor resistive switching artificial synapse neuromorphic computing

ON THE CENTRAL RELAXING SCHEME Ⅱ: SYSTEMS OF HYPERBOLIC CONSERVATION LAWS

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Journal of Computational Mathematics 2001年第6期19卷 571-582页

作者： Hua-zhong tang (school of mathematical {3., Peking {4., beijing 100871, china) (LSEC,ICMSEC Academy of Mathematics and Systems {3., Chinese Academy of {3., beijing 100080, china) school of mathematical sciences Peking University Beijing 100871 China

This paper continues to study the central relaxing schemes for system of hyperbolic conservation laws, based on the local relaxation approximation. Two classes of relaxing systems with stiff source term are introduced to approximate system of conservation laws in curvilinear coordinates. Based on them, the semi-implicit relaxing schemes are con- structed as in [6, 12] without using any linear or nonlinear Riemann solvers. Numerical experiments for one-dimensional and two-dimensional problems are presented to demon- strate the performance and resolution of the current schemes.

关键词： Hyperbolic conservation laws The relaxing system The central relaxing schemes The Euler equations.

Infinitely many radial solutions to elliptic prob-lems with critical Sobolev and Hardy terms

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Science china Mathematics 2008年第9期51卷 1609-1618页

作者： tang ZhongWei school of mathematical {3., {4. Normal university, {4. 100875, china 1. school of mathematical sciences Beijing Normal University Beijing 100875 China

Let Ω ? ? N be a ball centered at the origin with radius R > 0 and N ? 7, 2* = $ \frac{{2N}} {{N - 2}} $ . We obtain the existence of infinitely many radial solutions for the Dirichlet problem ?Δu = $ \frac{\mu } {{|x|^2 }}u + |u|^{2^* - 2} u + \lambda u $ in Ω, u = 0 on ?Ω for suitable positive numbers μ and λ. Such solutions are characterized by the number of their nodes.

关键词： nodal solutions compactness critical Sobolev and Hardy terms 3.J60 3.B3.

Uniqueness and local stability for the inverse scattering problem of determining the cavity

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Science china Mathematics 2005年第8期48卷 1113-1123页

作者： FENG Lixin & MA Fuming LMAM, school of mathematical sciences, Peking {3., {4. 100871, china school of mathematical sciences, Heilongjiang {3., Harbin 150080, china school of mathematical sciences, Jilin {3., Changchun 13.012, china 1. LMAM School of Mathematical Sciences Peking University 100871 Beijing China 2. school of mathematical sciences Heilongjiang University 150080 Harbin China 3. school of mathematical sciences Jilin University 130012 Changchun China

Considering a time-harmonic electromagnetic plane wave incident on an arbitrarily shaped open cavity embedded in infinite ground plane, the physical process is modelled by Maxwell's equations. We investigate the inverse problem of determining the shape of the open cavity from the information of the measured scattered field. Results on the uniqueness and the local stability of the inverse problem in the 2-dimensional TM (transverse magnetic) polarization are proved in this paper.

关键词： uniqueness, stability, Maxwell's equations, inverse scattering problem.

Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2, 3. ZHANG Jin4.1. Institute of Geodesy and Geophysics, Chinese Academy of sciences, Wuhan 4.0}077, china 2. Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, Chinese Academy of sciences, Wuhan 4.0}077, china 3. graduate school of Chinese Academy of sciences, beijing 10004., china 4. Department of Surveying and Mapping, Taiyuan {14. of Technology, Taiyuan 03.024. china Taiyuan Univ Technol Dept Surveying & Mapping Taiyuan 030024 Peoples R China Chinese Acad Sci Inst Geodesy & Geophys Key Lab Dynam Geodesy Wuhan 430077 Peoples R China Chinese Acad Sci Grad Sch Beijing 100049 Peoples R China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine