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International Journal of Mining Science and Technology 2023年第6期33卷 783-791页

作者： Haoyong Yu Yangge Zhu liang lu Xiaoxing Hu Songqing Li State Key Laboratory of Mineral Processing Science and Technology BGRIMM Technology GroupBeijing 102628China

This study aims to investigate the effect of a cationic-anionic mixed collector(dodecyltrimethyl ammonium bromide/sodium oleate(DTAB/NaOL)on the selective separation of apatite,dolomite,and potassium ***,several experimental methods,including flotation experiments,zeta-potential detection,microcalorimetry detection,XPS analysis and FTIR measurements,were *** flotation tests showed that dolomite and potassium feldspar can be successfully removed from apatite simultaneously when the molar ratio of DTAB to NaOL was 2:1 with pH ***-potential and microcalorimetry detection suggested that NaOL and DTAB were adsorbed on the surface of dolomite and potassium feldspar respectively,and part of NaOL and DTAB formed co-adsorption on the surface of potassium feldspar to enhance the floatability of potassium *** XPS and FTIR spectra analysis demonstrated that the cationic collector,DTAB,was first adsorbed on the surface of potassium feldspar through electrostatic attraction in the DTAB/NaOL mixture ***,the anionic NaOL collector and cationic DTAB collector form an electron neutralisation complex,thereby resulting in co-adsorption on the surface of potassium *** was chemically reacted and adsorbed on dolomite surface,but almost no collector was adsorbed on apatite ***,the adsorption models of different collectors on mineral surface were obtained.

关键词： Flotation Mixed collectors Apatite Potassium feldspar Dolomite

Substituent Effects on Direct Arylation Polycondensation and Optical Properties of Alternating Fluorene-Thiophene Copolymers

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Chinese Journal of Polymer Science 2015年第5期33卷 783-791页

作者： Min-min Sun 王文 lu-ying liang Shu-hui Yan Ming-lu Zhou 凌启淡 Fujian Key Laboratory of Polymer Materials College of Materials Science and EngineeringFujian Normal University

Four thiophene derivatives were prepared by replacing the 3,4 positions of thiophene by―OCH3, ―CH3―COOCH3 and ―CN, respectively. The polycondensations via direct arylation took place between the four thiophene derivatives and 2,7-dibromo-9,9-dioctylfluorene under six various catalytic conditions to investigate the substituent effects. The substituent can affect the electron cloud density of the active C―H bond, which can be monitored by the NMR chemical shift. The experimental results show that the reactivity decreases with increasing the chemical shift of active C―H bonds in the four thiophene derivatives, and thus can promote the direct arylation polycondensation. This phenomenon is explained by the electrophilic aromatic substitution（SEAr） mechanism. UV-Visible absorption and photoluminescence were studied to investigate the substituent effect on optical properties of the four copolymers. The results show that these alternating fluorene-thiophene copolymers with different substituents are good fluorescent materials and promising in PLED applications.

关键词： Direct arylation polycondensation Alternating copolymers Substituent effects Chemical shift

Changes in fossil-fuel carbon emissions in response to interannual and interdecadal temperature variability

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Chinese Science Bulletin 2011年第3期56卷 319-324页

作者： QIAN WeiHong lu Bo liang HaoYuan Monsoon and Environment Research Group School of Physics Peking University Beijing 100871 China

Relationships on interannual and interdecadal timescales among global mean air temperature,CO2 concentrations and fossil-fuel carbon emissions in four major developed countries (the United States,the United Kingdom,France,and Germany) were *** an interannual timescale,the United States fossil-fuel carbon emissions tend to increase during cold winters and decrease during warm winters,which is opposite to the situation in *** an interdecadal timescale,cold (warm) periods both in the United States and globally agree with high (low) periods of fossil-fuel carbon emissions,with the temperature variability leading by 5–7 *** leading correlation on the interdecadal timescale and the asymmetry in seasonal correlation on the interannual timescale indicate that temperature variability is a possible cause of changes in fossil-fuel carbon emissions.

关键词：年际时间尺度碳排放量化石燃料年代际温度变率反应全球平均气温

Dynamically Computing Approximate Frequency Counts in Sliding Window over Data Stream

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 283-288页

作者： NIE Guo-liang lu Zheng-ding School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074Hubei China

This paper presents two one-pass algorithms for dynamically computing frequency counts in sliding window over a data stream-computing frequency counts exceeding user-specified threshold ε. The first algorithm constructs subwindows and deletes expired sub-windows periodically in sliding window, and each sub-window maintains a summary data structure. The first algorithm outputs at most 1/ε ＋ 1 elements for frequency queries over the most recent N elements. The second algorithm adapts multiple levels method to deal with data stream. Once the sketch of the most recent N elements has been constructed, the second algorithm can provides the answers to the frequency queries over the most recent n （ n≤N） elements. The second algorithm outputs at most 1/ε ＋ 2 elements. The analytical and experimental results show that our algorithms are accurate and effective.

关键词： data stream sliding window approximation algorithms frequency counts

Design of switched linear systems in the presence of actuator saturation and L-infinity disturbances

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控制理论与应用（英文版） 2010年第3期8卷 333-343页

作者： liang lu Zongli LIN Haijun FANG Department of Automation Shanghai/iao Tong University Shanghai 200030 China Department of Electrical and Computer Engineering University of Virginia P.O. Box 400743 Charlottesville VA 22904-4743 USA MKS Instrument 100 Highpower Road Rochester NY 14623 USA

This paper considers the problem of disturbance tolerance/rejection of a switched system resulting from a family of linear systems subject to actuator saturation and E-infinity disturbances. For a given set of linear feedback gains, a given switching scheme and a given bound on the E-infinity norm of the disturbances, conditions are established, in terms of linear or bilinear matrix inequalities, under which a set of a certain form is invariant for a given switched linear system in the presence of actuator saturation and E-infinity disturbances, and the closed-loop system possesses a certain level of disturbance rejection capability. With these conditions, the design of feedback gains and switching scheme can be formulated and solved as constrained optimization problems. Disturbance tolerance is measured by the largest bound on the disturbances for which the trajectories starting from a given set remain bounded. Disturbance rejection is measured either by the E-infinity norm of the system output or by the system＇s ability to steer its state into and/or keep it within a small neighborhood of the origin. In the event that all systems in the family are identical, the switched system reduces to a single system under a switching feedback law. Simulation results show that such a single system under a switching feedback law could have stronger disturbance tolerance/rejection capability than a single linear feedback law can.

关键词： Actuator saturation Disturbance rejection Disturbance tolerance L-infinity performance Set invariance Switched systems

Approximate Analytical Solutions to the Generalized P(o)schl-Teller Potential in D Dimensions

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Chinese Physics Letters 2012年第2期29卷 21-24页

作者： Hassanabadi Hassan Yazarloo Bentol Hoda lu liang-liang Department of Physics Shahrood University of TechnologyP.O.Box ***-316 ShahroodIran Department of Physics College of Physics and Electronic EngineeringGuangzhou UniversityGuangzhou 510006

The Schr(o)dinger equation for the generalized P(o)schl-Teller potential with the centrifugal term is investigated *** Nikiforov-Uvarov method is used in the calculations and the eigenfunctions as well as the energy eigenvalues obtained after a proper Pekeris-type *** useful expectation values and the oscillator strength are reported.

关键词： approximation Teller expectation

Solvent-free esterification of poly(vinyl alcohol) and maleic anhydride through mechanochemical reaction

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Chinese Chemical Letters 2007年第11期18卷 1353-1356页

作者： Bo Zhao Can Hui lu Mei liang State Key Laboratory of Polymer Materials Engineering Polymer Research Institute Sichuan University Chengdu 610065 China

A solid-state mechanochemical processing, that is, pan-milling, was used to conduct the esterification of poly（vinyl alcohol）（PVA） with maleic anhydride （MA） through stress-induced reaction. FTIR spectrum study indicated the presence of ester linkages and olefinic double bonds in maleic anhydride cross-linked PVA. Thermal properties of the cross-linked product were characterized by DSC. The results showed its glass transition temperature was 20 ℃ higher than the original linear PVA and the thermal stability was also improved.

关键词： Mechanochemical synthesis Estedfication Poly(vinyl alcohol) Maleic anhydride

On Edge Connectivity and Parity Factor

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Acta Mathematica Sinica,English Series 2015年第5期31卷 772-776页

作者： Hong liang lu Wei WANG Yuqing LIN School of Mathematics and Statistic Xi'an Jiaotong University School of Electrical Engineering and Computer Science The University of Newcastle

By Petersen＇s Theorem, a bridgeless cubic graph has a 2-factor. Fleischner （Discrete Math., 101, 33-37 （1992）） has extended this result to bridgeless graphs of minimum degree at least three by showing that every such graph has an even factor without isolated vertices. Let me〉 0 be even and mo〉 0 be odd. In this paper, we prove that every me-edge-connected graph with minimum degree at least me ＋ 1 contains an even factor with minimum degree at least me and every （mo ＋ 1）- edge-connected graph contains an odd factor with minimum degree at least too, which further extends Fleischner＇s result. Moreover, we show that our results are best possible.

关键词： Edge connectivity parity factor

Exploring fluorescent covalent organic frameworks for selective sensing of Fe^3＋

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Science China Chemistry 2018年第11期61卷 1470-1474页

作者： lu-liang Wang Cheng-Xiong Yang Xiu-Ping Yan College of Chemistry Research Center for Analytical Sciences Tianjin Key Laboratory of Molecular Recognition and Biosensing State Key Laboratory of Medicinal Chemical Biology Nankai University Tianjin 300071 China Institute of Analytical Food Safety School of Food Science and Technology Jiangnan University Wuxi 214122 China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300071 China

Covalent organic frameworks （COFs） have been widely applied in gas capture and separation, but the fluorescent property of COFs with large n-conjugated system tends to be underexplored. Here we report the fluorescent properties of several COFs including TaTa, DhaTab, TRITER- 1 and TzDa and the effect of metal ions of Na＋, Mg2＋, K＋, Ca2＋, Cu2＋, Zn2＋, Pb2＋, Ag＋, Cd2＋ and Fe3＋ on the fluorescence of these COFs. The results show that only Fe3＋ significantly quenched the fluorescence of the studied COFs. The possibility of the four COFs for selective sensing of Fe3＋ was demonstrated. The possible mechanism of the effect of Fe3＋ on the fluorescence of the COFs was based on the absorption competition quenching.

关键词： fluorescence covalent organic frameworks iron ion fluorescent probe

Novel two-dimensional transition metal chalcogenides created by epitaxial growth

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Science China(Physics,Mechanics & Astronomy) 2021年第10期64卷 23-37页

作者： Hong-liang lu Yu-Yang Zhang Xiao Lin Hong-Jun Gao Institute of Physics and University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

Two-dimensional(2D) materials have been a very important field in condensed matter physics, materials science, chemistry, and electronics. In a variety of 2D materials, transition metal chalcogenides are of particular interest due to their unique structures and rich properties. In this review, we introduce a series of 2D transition metal chalcogenides prepared by epitaxial growth. We show that not only 2D transition metal dichalcogenides can be grown, but also the transition metal chalcogenides that do not have bulk counterparts, and even patterned transition metal chalcogenides can be fabricated. We discuss the formation mechanisms of the novel structures, their interesting properties, and potential applications of these 2D transition metal chalcogenides. Finally, we give a summary and some perspectives on future studies.

关键词： 2D materials transition metal chalcogenides epitaxial growth