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Theoretical and experimental study on high-entropy flotation of micro-fine cassiterite

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International Journal of Mining Science and Technology 2025年第1期35卷 19-39页

作者： Shuming wen Yongchao Miao Yanyu Tang Zhengyong Song Qicheng feng State key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

Tin is a critical metal for various industries,making its recovery from low-grade cassiterite ores *** study aimed to optimize the flotation recovery of cassiterite using multi-component collector *** collectors were initially selected through micro-flotation tests,leading to the identification of optimal proportions for a four-component collector system(SHA-OHA-SPA-DBIA in a 4:3:2:1 ratio).Molecular dynamics simulations and surface tension tests were used to investigate the micellar behavior of these collectors in aqueous *** adsorption characteristics were quantified using microcalorimetry,enabling the determination of collection entropy and changes in Gibbs free *** four-component collector system showed the highest entropy change and the most favorable Gibbs free energy,leading to a cassiterite recovery of above 90%at a concentration of 8.0×10^(5)mol/*** analytical techniques were employed to systematically characterize the adsorption *** findings revealed a positive correlation between the adsorption products formed by the multicomponent collectors on the cassiterite surface and the entropy ***-scale testing of the high-entropy collector system produced a tin concentrate with an Sn grade of 6.17%and an Sn recovery of 82.43%,demonstrating its substantial potential for practical applications in cassiterite flotation.

关键词： High-entropy Flotation Cassiterite Adsorption Molecular dynamics QCM-D

A nuclide identification method ofγspectrum and model building based on the transformer

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Nuclear Science and Techniques 2025年第1期36卷 80-93页

作者： Fei Li Chu-Yang Luo Ying-Zi wen Sheng Lv feng Cheng Guo-Qiang Zeng Jian-feng Jiang Bing-Hai Li College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610000China Applied Nuclear Technology in Geosciences key Laboratory of Sichuan Province Chengdu 610000China Department of Physics Universitat Politècnica de CatalunyaBarcelona 08028Spain Airborne Survey and Remote Sensing Center of Nuclear Industry Shijiazhuang 050000China Hebei key Laboratory of Airborne Detection and Remote Sensing Technology Shijiazhuang 050000China

In current neural network algorithms for nuclide identification in high-background,poor-resolution detectors,traditional network paradigms including back-propagation networks,convolutional neural networks,recurrent neural networks,etc.,have been limited in research on γ spectrum analysis because of their inherent mathematical *** is difficult to make progress in terms of training data requirements and prediction *** contrast to traditional network paradigms,network models based on the transformer structure have the characteristics of parallel computing,position encoding,and deep stacking,which have enabled good performance in natural language processing tasks in recent ***,in this paper,a transformer-based neural network (TBNN) model is proposed to achieve nuclide identification for the first ***,the Geant4 program was used to generate the basic single-nuclide energy spectrum through Monte Carlo simulations.A multi-nuclide energy spectrum database was established for neural network training using random matrices of γ-ray energy,activity,and *** on the encoder–decoder structure,a network topology based on the transformer was built,transforming the 1024-channel energy spectrum data into a 32×32 energy spectrum sequence as the model *** experiments and adjustments of model parameters,including the learning rate of the TBNN model,number of attention heads,and number of network stacking layers,the overall recognition rate reached 98.7%.Additionally,this database was used for training AI models such as back-propagation networks,convolutional neural networks,residual networks,and long shortterm memory neural networks,with overall recognition rates of 92.8%,95.3%,96.3%,and 96.6%,*** indicates that the TBNN model exhibited better nuclide identification among these AI models,providing an important reference and theoretical basis for the practical application of transformers in the qualitative and quantitativ

关键词： Nuclide identification Neural network Transformer

Edge supercurrent in Josephson junctions based on topological materials

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 1-12页

作者： Junjie Qi Chui-Zhen Chen Juntao Song Jie Liu ke He Qing-feng Sun X.C.Xie Beijing Academy of Quantum Information Sciences Beijing 100193China School of Physical Science and Technology Soochow UniversitySuzhou 215006China Institute for Advanced Study Soochow UniversitySuzhou 215006China College of Physics and Hebei Advanced Thin Films Laboratory Hebei Normal UniversityShijiazhuang 050024China School of Physics Xi’an Jiaotong UniversityMinistry of Education Key Laboratory for Non-Equilibrium Synthesis and Modulation of Condensed MatterXi’an 710049China State key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Frontier Science Center for Quantum Information Beijing 100084China Hefei National Laboratory Hefei 230088China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan UniversityShanghai 200433China

The interplay between novel topological states and superconductivity has garnered substantial interest due to its potential for topological quantum *** Josephson effect serves as a useful probe for edge superconductivity in these hybrid topological *** Josephson junctions based on topological materials,supercurrents exhibit unique quantum interference patterns,including the conventional Fraunhofer oscillations,theΦ_(0)-periodic oscillation,and the 2Φ_(0)-periodic oscillation in response to the external magnetic field(Φ_(0)=h/2e is the flux quantum,h the Planck constant,and e the electron charge).These interference patterns stem from varied Andreev reflection mechanisms and the associated current density *** review seeks to comprehensively examine the theoretical and experimental advancements in understanding the quantum interference patterns of edge supercurrents in Josephson junctions based on quantum spin Hall,quantum Hall,and quantum anomalous Hall systems.

关键词： quantum Hall effect quantum spin Hall effect quantum anomalous Hall effect Josephson junction edge supercurrent Andreev reflection

Accumulation characteristics and fate modeling of phthalic acid esters in surface water from the Three Gorges Reservoir area,China

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Journal of Environmental Sciences 2025年第3期149卷 46-56页

作者： Shuai Sun Bing Zhang Junjie Hu wen Gu ZhenWang Deling Fan feng Ge Lili Shi LeiWang Nanjing Institute of Environmental Science Ministry of Ecology and Environment of the People’s Republic of ChinaNanjing 210042China key Laboratory of Pesticide Environmental Assessment and Pollution Control Ministry of Ecology and Environment of the People’s Republic of ChinaNanjing 210042China Solid Waste and Chemicals Management Center Ministry of Ecology and Environment of the People’s Republic of ChinaBeijing 100029China

Phthalic acid esters(PAEs)are a group of compounds widespread in the *** investigate the occurrence and accumulation characteristics of PAEs,surface water samples were collected from the Three Gorges Reservoir area,*** total concentrations of∑_(11)analyzed PAEs(11PAEs)in the collected water samples ranging from 197.7 to 1,409.3 ng/L(mean±IQR:583.1±308.4 ng/L).While DEHP was the most frequently detected PAE,DnBP and DnNP were the most predominant PAEs in the analyzed water samples with a mean contribution of 63.3%of the∑_(11)*** concentrations of the∑_(11)PAEs in the water samples from the upper reaches of the Yangtze River were significantly higher than those from themiddle *** better understand the transport and fate of the PAEs,seven detected PAEs were modeled by Quantitative Water Air Sediment Interaction(QWASI).The simulated and measured values were close for most PAEs,and differences are within one order of magnitude even for the worst *** all simulated PAEs,water and particle inflow were main sources in the reservoir,whereas water outflow and degradation in water were important removal *** contribution ratios of different sources/losses varied fromPAEs,depending on their *** calculated risk quotients of DnNP in the Three Gorges Reservoir area whether based onmonitoring or simulating results were all far exceeded the safety threshold value,implying the occurrence of this PAE compound may cause potential adverse effects for the aquatic ecology of the Three Gorges Reservoir area.

关键词： Phthalic esters Surface water Transport and fate Three Gorges Reservoir area Risk assessment

Flotation separation of chalcopyrite from pyrite using mineral fulvic acid as selective depressant under weakly alkaline conditions

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中国有色金属学报 2025年第1期35卷 313-325页

作者： Zhi-hao SHEN Shu-ming wen Jia-mei HAO Qi-cheng feng State key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a *** experiments showed that MFA produced a stronger inhibition effect on pyrite than on *** separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately *** copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,*** adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the *** force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.

关键词： mineral fulvic acid chalcopyrite pyrite flotation separation

胆甾醇修饰羟基喹啉锌的聚集诱导荧光蓝移(英文)

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物理化学学报 2010年第7期26卷 1929-1933页

作者：冯文科孔胜肖立新王树峰龚旗煌北京大学物理系、人工微结构与介观物理国家重点实验室北京100871

用稳态光谱以及皮秒瞬态荧光光谱研究了新型有机电致发光分子胆甾醇修饰羟基喹啉锌(Zn(ChQ)2)的聚集诱导荧光蓝移性质.在Zn(ChQ)2的极性溶剂溶液中,分子激发后会发生从胆甾醇基团向喹啉环的光致电子转移,转移后形成了"扭转的分子内电荷... 详细信息

用稳态光谱以及皮秒瞬态荧光光谱研究了新型有机电致发光分子胆甾醇修饰羟基喹啉锌(Zn(ChQ)2)的聚集诱导荧光蓝移性质.在Zn(ChQ)2的极性溶剂溶液中,分子激发后会发生从胆甾醇基团向喹啉环的光致电子转移,转移后形成了"扭转的分子内电荷转移态"作为新的荧光发射态.而在薄膜态中,分子由于聚集产生空间位阻,不能形成新的荧光发射态,相对于极性溶剂中,产生聚集荧光增强效应,荧光发射峰会蓝移,发射强度会增强.在薄膜态中,全波长上的超快荧光衰减说明存在分子间光致能量转移过程.

关键词：分子内电子转移羟基喹啉锌胆甾醇聚集诱导荧光蓝移

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO_(2) photoreduction

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Science China Chemistry 2025年第1期68卷 201-208页

作者： Hui-feng Wang wen-Jie Shi Yu-Xin Yang Bao-Xia Dong Tong-Bu Lu Di-Chang Zhong School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

Dinuclear metal synergistic catalysis(DMSC)has been proved powerful in boosting CO_(2)reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework(MOF),obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center(M-In),three MOFs with dinuclear homometallic catalytic centers(MM-In),and three MOFs with dinuclear heterometallic catalytic centers(MM’-In,M/M’=Co(II),Ni(II),Zn(II)).It was found that all these MOFs can serve as catalysts for photochemical CO_(2)reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g^(-1)h^(-1),which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO_(2)reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO_(2)reduction.

关键词： metal-organic frameworks dinuclear metal centers synergistic catalysis CO_(2)reduction photocatalysis

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试论中介运动与结果的关系

陕西省行政学院陕西省经济管理干部学院学报 2002年第2期16卷 32-33页

作者：温锋科陕西省行政学院陕西西安710068

分析中介运动与结果的关系,对加深因果关系这一哲学范畴的理解有实质意义。“中介运动消失在结果中”是这一范畴的重要内容;正确把握这一命题,对于克服工作中的盲目性,增强预见性和科学性具有重大意义。

关键词：因果关系中介中介运动结果辨证关系

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公务员管理与公共服务中的几个问题探析

陕西省行政学院陕西省经济管理干部学院学报 2006年第2期20卷 39-42页

作者：温锋科陕西省行政学院西安710068

明确“两个定位,”即价值理念定位和目标要求定位,有针对性地解决公务员管理中的一系列现实问题,对于当前加强公务员管理和提高公共服务水平具有重要作用。塑造公务员公共精神是价值理念定位;提高公务员素质与公共管理效能是目标要求定... 详细信息

明确“两个定位,”即价值理念定位和目标要求定位,有针对性地解决公务员管理中的一系列现实问题,对于当前加强公务员管理和提高公共服务水平具有重要作用。塑造公务员公共精神是价值理念定位;提高公务员素质与公共管理效能是目标要求定位。当前,加强公务员管理和提高公共管理效能,既要重制度、措施、机制上的创新,更要重视理念、精神的塑造、内功的锤炼。

关键词：公务员公共精神管理效能公共服务