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Sufficient Conditions for Maximally Edge-Connected Hypergraphs

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Journal of the Operations Research Society of China 2021年第1期9卷 119-129页

作者： lin-Ken tong Er-Fang Shan Department of Mathematics Shanghai UniversityShanghai 200444China School of Management Shanghai UniversityShanghai 200444China

The edge-connectivity of a graph or a hypergraph is defined as the minimum number of edges whose removal renders the graph or hypergraph disconnected.A graph or hypergraph is called maximally edge-connected if the edge-connectivity equals its minimum *** this paper,we show that some classical sufficient conditions for graphs to be maximally edge-connected can be generalized to hypergraphs.

关键词： Hypergraph Edge-connectivity Maximally edge-connected

Biooxidation-thiosulfate leaching of refractory gold concentrate

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International Journal of Minerals,Metallurgy and Materials 2020年第8期27卷 1075-1082页

作者： He-fei Zhao Hong-ying Yang lin-lin tong Qin Zhang Ye Kong Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

A process of biooxidation followed by thiosulfate leaching of gold from refractory gold concentrate was *** studies on the concentrate showed that very fine gold grains(<10μm)were encapsulated in pyrite and arsenopyrite,while the proportion of monomer gold was only 21%.The gold-bearing sample was identified as a high-sulfur fine-sized wrapped-type refractory gold *** gold leaching efficiency obtained by direct cyanidation was only 59.86%.After biooxidation pretreatment,the sulfide minerals were almost completely decomposed,92 wt%of the mineral particles of the biooxidation residue were decreased to<38μm,and the proportion of monomer gold in the biooxidation residue was over 86%.Meanwhile,the gold content in the biooxidation residue was enriched to 55.60 g/t,and the S,Fe,and As contents were reduced to approximately 19.8 wt%,6.97 wt%,and 0.13 wt%,*** thiosulfate was used for gold extraction from the biooxidation residue of the refractory gold *** results showed that the optimal reagent conditions were 0.18 M thiosulfate,0.02 M copper(II),1.0 M ammonia,and 0.24 M *** these conditions,a maximum gold leaching efficiency of 85.05%was obtained.

关键词： thiosulfate leaching gold biooxidation refractory gold concentrate process mineralogy

Dynamic modeling and parameter identification of a gun saddle ring

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Defence Technology（防务技术） 2020年第2期16卷 325-333页

作者： tong lin lin-fang Qian Qiang Yin Shi-yu Chen Tai-su Liu School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China

In this study,a theoretical nonlinear dynamic model was established for a saddle ring based on a dynamic force analysis of the launching process and the structure according to contact-impact *** ADAMS software was used to build a parameterized dynamic model of the saddle ring.A parameter identification method for the ring was proposed based on the particle swarm optimization algorithm.A loading test was designed and performed several times at different elevation *** response histories of the saddle ring with different loads were then *** parameters of the saddle ring dynamic model were identified from statistics generated at a 500 elevation angle to verify the feasibility and accuracy of the proposed *** actual loading history of the ring at a 70°elevation angle was taken as the model *** response histories of the ring under these working conditions were obtained through a *** simulation results agreed with the actual ***,the effectiveness and applicability of the proposed dynamic model were verified,and it provides an effective method for modeling saddle rings.

关键词： Gun saddle ring Dynamic response Parameter identification Particle swarm optimization

Study on the mechanical activation of malachite and the leaching of complex copper ore in the Luanshya mining area, Zambia

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 292-300页

作者： Gai-rong Wang Hong-ying Yang Yuan-yuan Liu lin-lin tong Ali Auwalu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China CNMC Luanshya Copper Mines Plc(CLM) Independence AvenueLuanshya City 90456Zambia

Mechanical activation(MA) of malachite was carried out by dry planetary grinding(DPG) and wet Isa grinding(WIG) methods. When the rotational speed was increased to 400 r/min in DPG, the specific surface area of malachite reached the maximum and the particle size reached the minimum of 0.7–100 μm. Agglomeration occurred between mineral particles when the rotational speed was increased to 580 r/min in ***, no agglomeration was observed among particles with sizes 0.4–3 μm in WIG. X-ray diffraction analysis showed that, at a 580 r/min rotational speed in DPG, the amorphization degree of malachite was 53.12%, whereas that in WIG was 71.40%, indicating that MA led to amorphization and distortion of crystal structures. In addition, in the Fourier transform infrared(FT-IR) spectra of activated malachite, the bands associated with –OH, CO_3^(2-)and metal lattice vibrations of Cu–O and Cu–OH were weakened, and a new H–O–H bending mode and peaks of gaseous CO_2 appeared, indicating that MA decreased the band energy, enhanced dihydroxylation, and increased the chemical reactivity of the ***, the leaching behavior of copper ore was greatly improved by MA.

关键词： malachite mechanical activation crystal structure copper ore Zambia

Synthesis and photophysical properties of linear and hy-perbranched conjugated polymer

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Chinese Science Bulletin 2001年第8期46卷 636-641页

作者： Qingguo He tong lin Fenglian Bai Chinese Acad Sci Inst Chem Ctr Mol Sci Lab Organ Solids Beijing 100080 Peoples R China

A novel light-emitting alternating copolymer, known as hyperbranched conjugated polymer (HPV), has been designed and synthesized by Wittig reaction, and so have its linear counterparts, including MPV and PPV. FTIR, 1H NMR, 13C NMR and GPC were combined to characterize these polymers. Their photophysical properties were investigated both in solution and in solid film. Interestingly, almost the same maxima of absorption and emission wavelengths were observed for the solution of HPV and MPV in CH2Cl2 respectively, located at the shorter wavelength region related to PPV. In addition, the absorption peak of HPV film blue shifted while its emission peak red shifted as MPV compared with the case of its CH2Cl2 solution. However, both the absorption and emission spectra of the PPV film showed red shift, which resulted from a special electronic structure.

关键词： hyperbranched conjugated polymer linear conjugated polymer photophysical properties electronic structure.

Strength-toughness improvement of 13Cr4NiMo martensitic stainless steel with thermal cyclic heat treatment

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Journal of Iron and Steel Research International 2023年第8期30卷 1499-1510页

作者： Jie Xiong Yao-lin tong Jie-long Peng Sheng-hua Zhang State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures MOE Key Laboratory of New Processing Technology for Nonferrous Metals and Materialsand School of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004GuangxiChina Key Laboratory of High Performance Structural Materials and Thermo-Surface Processing Education Department of Guangxi Zhuang Autonomous RegionGuangxi UniversityNanning 530004GuangxiChina

To improve the strength-toughness of 13Cr4NiMo martensitic stainless steel(13-4MSS),a thermal cyclic heat treatment(TCHT)combined with the advantage of tempering was *** microstructures were characterized by scanning electron microscopy,X-ray diffraction and electron backscattered diffraction,and the mechanical behaviors in terms of tensile properties and impact toughness were analyzed in correlation with microstructural *** was found that grains and the martensitic matrix were refined by TCHT through the cyclic quenching transformation and austenite recrystallization,which was conducive to more nucleation quantity of reversed austenite during ***-sphericalcap nucleation model was used to explain the effect of refined grains of TCHT on the nucleation of reversed *** refinement by TCHT improved the brittle fracture stress to reduce the ductile-brittle transition temperature and thus improved the cryogenic impact toughness of *** austenite distributed at the martensitic lath boundary enhances the crack arrest performance and increases the britle fracture *** is concluded that reasonable TCHT plus tempering process significantly improves the strength-toughness of 13-4MSS,reflecting the comprehensive effect of grain refinement and reversed austenite.

关键词： Strength-Toughness 13Cr4NiMo martensitic stainless steel Thermal cyclic heat treatment Grain refinement Reversed austenite

Progress in nanostructured photoanodes for dye-sensitized solar cells

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Frontiers of Materials Science 2016年第3期10卷 225-237页

作者： Xueyang LIU Jian FANG Yong LIU tong lin Institute for Frontier Materials Deakin University Geelong VIC 3216 Australia Institute of Advanced Materials for Nano-Bio Applications Wenzhou Medical University Wenzhou 325027 China

Solar cells represent a principal energy technology to convert light into electricity. Commercial solar cells are at present predominately produced by single- or multi-crystalline silicon wafers. The main drawback to silicon-based solar cells, however, is high material and manufacturing costs. Dye-sensitized solar cells （DSSCs） have attracted much attention during recent years because of the low production cost and other advantages. The photoanode （working electrode） plays a key role in determining the performance of DSSCs. In particular, nanostructured photoanodes with a large surface area, high electron transfer efficiency, and low electron recombination facilitate to prepare DSSCs with high energy conversion efficiency. In this review article, we summarize recent progress in the development of novel photoanodes for DSSCs. Effect of semiconductor material （e.g. TiO2, ZnO, SnO2, N2O5, and nano carbon）, preparation, morphology and structure （e.g. nanoparticles, nanorods, nanofibers, nanotubes, fiber/ particle composites, and hierarchical structure） on photovoltaic performance of DSSCs is described. The possibility of replacing silicon-based solar cells with DSSCs is discussed.

关键词： dye-sensitized solar cell (DSSC) nanostructure photoanode

砂磨固相法快速制备Ca掺杂的BaTiO_(3)陶瓷及其结构和电性能研究

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湖北大学学报（自然科学版） 2025年第1期47卷 153-162页

作者：林彤郭全胜潘瑞琨湖北大学材料科学与工程学院湖北武汉430062

Ca^(2+)可掺杂在BaTiO_(3)(BT)陶瓷的A及B位。本文中系统研究B位掺杂Ca元素对BaTiO_(3)陶瓷的相结构与微观形貌、介电性能、可靠性和铁电性能的影响。采用砂磨-固相反应-造粒-压片方法制备BaTi_(1-x)Ca_(x)O_(3)-x(BTC-x,其中x=0,0.01,0... 详细信息

Ca^(2+)可掺杂在BaTiO_(3)(BT)陶瓷的A及B位。本文中系统研究B位掺杂Ca元素对BaTiO_(3)陶瓷的相结构与微观形貌、介电性能、可靠性和铁电性能的影响。采用砂磨-固相反应-造粒-压片方法制备BaTi_(1-x)Ca_(x)O_(3)-x(BTC-x,其中x=0,0.01,0.02,0.03,0.04)陶瓷样品。随着Ca掺杂量的增加,陶瓷样品的晶粒尺寸先增大后减小,样品居里温度T_(c)持续降低,其中BTC-1样品具有较高和较宽的介电峰及极小的损耗。利用高温阻抗谱对样品进行了可靠性分析,可知BTC-2的电学失效的风险最分散。由P-E电滞回线可知:在掺杂样品中,BTC-2的P_(max)值最大,归因于其内部可供极化的空间电荷浓度高。综上所述,当Ca元素在BT的B位掺杂量较低时,BTC材料具有良好的介电性能及可靠性,能应用于片式多层陶瓷电容器(Multi-layer Ceramic Capacitors,MLCC)行业。

关键词：固相烧结 B位掺杂 BaTiO_(3)陶瓷介电性能

QSAR Studies on PCDD/Fs by Kernel PLS

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Chemical Research in Chinese Universities 2008年第5期24卷 541-545页

作者： TANG Kai-lin LI tong-hua CHEN Kai Department of Chemistry Tongji University Shanghai 200092 P. R. China

QSPR models of PCDD/Fs were generated by means of kernel partial least squares. The molecular distance-edge vector method was used as descriptors to get model I for predicting PCDD/Fs retention behavior. The chlorinated positions were also used and model II was obtained. In studied cases, the predictive ability of the KPLS model is comparable or superior to those of PLS and ANN. The results indicate that KPLS can be used as an alternative powerful modeling tool for QSPR studies.

关键词： QSPR modeling Kernel partial least squares PCDD/Fs