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The influence of temperature on rare earth flotation with naphthyl hydroxamic acid

Journal of Rare earths 2018年第1期36卷 99-107页

作者： Mei Li Kai Gao Dongliang Zhang Haijun Duan Linlin Ma Lan Huang school of Materials science and engineering Beijing University of Chemical Technology Inner Mongolia Key Laboratory of Rare earth Hydrometallurgy and Light Rare earth Application Inner Mongolia University of Science and Technology school of Material and Metallurgy Inner Mongolia University of Science and Technology

The influence of temperature on the complex process of Bayan Obo rare earth （RE） ore flotation with a collector of naphthyl hydroxamic acid （LF8#） was investigated. Industrial test data shows that the grade and recovery of RE increase with the temperature. However, the proportion of bastnaesite in the bulk concentrate increases as the RE grade improves. Adsorption mechanism of LF8# on the surfaces of bastnaesite and monazite were confirmed via zeta potential, UV]Vis Spectrophotometer （UV]Vis）, Fourier transform infrared （FIR）, and X-ray photoelectron spectroscopy analyses （XPS）. Although the results indicate that the total amount of the LF8# adsorption on the surface of bastnaesite and monazite de- creases with increasing the temperature, the amount of stable adsorbed predominance of characteristic bonds （-C（~O）N-] from LF8# uptake on bastnaesite surfaces increases significantly at high tempera- tures. This conclusion indicates that the adsorption stability increases with increasing the temperature. For monazite, the amount of characteristic elements C and N in LF8# does not increase as the temper- ature increases on the mineral surface, but the proportion of characteristic bonds increases, which shows that the adsorption stability of LF8# on the surface of monazite also increases, but it is not as significant as bastnaesite, which may be one of the reasons that the floatability of bastnaesite is better than those of monazite. Pulp dispersion results show that the temperature improve the dispersions of both the gangue and RE minerals. This improved the flotation selectivity so that it favored RE minerals. The calculated bubble size distribution confirms that higher temperatures generate smaller bubbles, thereby increasing the bubble-particle collision probability and the recovery of RE minerals.

关键词： BastnaesiteMonaziteFlotationHydroxamic acidAdsorptionRare earths

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Congruent Feature Selection Method to Improve the Efficacy of Machine Learning-Based Classification in Medical Image Processing

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Computer Modeling in engineering & sciences 2025年第1期142卷 357-384页

作者： Mohd Anjum Naoufel Kraiem Hong Min Ashit Kumar Dutta Yousef Ibrahim Daradkeh Department of Computer engineering Aligarh Muslim UniversityAligarh202002India College of Computer science King Khalid UniversityAbha61413Saudi Arabia school of Computing Gachon UniversitySeongnam13120Republic of Korea Department of Computer science and Information Systems College of Applied SciencesAlMaarefa UniversityRiyadh13713Saudi Arabia Department of Computer engineering and Information College of Engineering in Wadi AlddawasirPrince Sattam bin Abdulaziz UniversityAl-Kharj16273Saudi Arabia

Machine learning(ML)is increasingly applied for medical image processing with appropriate learning *** applications include analyzing images of various organs,such as the brain,lung,eye,etc.,to identify specific flaws/diseases for *** primary concern of ML applications is the precise selection of flexible image features for pattern detection and region *** of the extracted image features are irrelevant and lead to an increase in computation ***,this article uses an analytical learning paradigm to design a Congruent Feature Selection Method to select the most relevant image *** process trains the learning paradigm using similarity and correlation-based features over different textural intensities and pixel *** similarity between the pixels over the various distribution patterns with high indexes is recommended for disease ***,the correlation based on intensity and distribution is analyzed to improve the feature selection ***,the more congruent pixels are sorted in the descending order of the selection,which identifies better regions than the ***,the learning paradigm is trained using intensity and region-based similarity to maximize the chances of ***,the probability of feature selection,regardless of the textures and medical image patterns,is *** process enhances the performance of ML applications for different medical image *** proposed method improves the accuracy,precision,and training rate by 13.19%,10.69%,and 11.06%,respectively,compared to other models for the selected *** mean error and selection time is also reduced by 12.56%and 13.56%,respectively,compared to the same models and dataset.

关键词： Computer vision feature selection machine learning region detection texture analysis image classification medical images

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Organic carbon isotope and molecular fossil records of vegetation evolution in central Loess Plateau since 450 kyr

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science China earth sciences 2016年第6期59卷 1206-1215页

作者： ZHOU Bin WALI Guzalnur Francien PETERSE Michael I BIRD Key Laboratory of Surficial Geochemistry (Ministry of Education) School of Earth Sciences and Engineering Nanjing University Utrecht University Department of Earth Sciences College of science Technology and Engineering and Centre for Tropical Environmental and Sustainability Science James Cook University

Significant uncertainties remain regarding the temporal evolution of natural vegetation during the Quaternary, and drivers of past vegetation change, on the Chinese Loess Plateau （CLP）. This study presents analyses of total organic carbon isotopic composition （TOC） and n-alkane ratios （C31/C27） from the Lingtai loess-palaeosol sequence on the central CLP over the last 450 kyr. The results demonstrate that the vegetation in this region comprised a mix of C3 and C4 plants of herb and woody growth-form. C3 plants dominated for most of the last 450 kyr, but this did not lead to extensive forest. C3 woody plants were more abundant in MIS9 （S3 period） and MIS5 （S 1 period） during warm and humid climate conditions. Herbs increased in the region since 130 kyr, possibly as a result of increased aridity. On the orbital timescales, there was a reduction of C3 herbal plants in MIS 11 （$4） than in M1S 12 （L5）, and in Holocene than in the last glacial period. Our isotope and n-alkane proxy records are in agreement with Artemisia pollen changes in the region, which is/was the dominant species in this area and varying due to different heat and water conditions between glacial and interglacial periods. Though the climate in MIS1 （SO） was similar to that in MIS11 （S4）, a significant increase in woody plants during the Holocene suggests the impact of human activities and ecological effects of changes in fire activity.

关键词： Carbon isotopic composition Leaf wax lipids C3/C4 variations Late Quaternary vegetation change Glacial/interglacial cycles

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Erosions on the southern Tibetan Plateau:Evidence from in-situ cosmogenic nuclides^(10)Be and^(26)Al in fluvial sediments

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Journal of Geographical sciences 2022年第2期32卷 333-357页

作者： ZHANG Xiaolong XU Sheng CUI Lifeng ZHANG Maoliang ZHAO Zhiqi LIU Congqiang Institute of Surface-earth System science School of Earth System ScienceTianjin UniversityTianjin 300072China school of earth science and Resources Chang'An UniversityXi’an 710054China

Investigating topographic and climatic controls on erosion at variable spatial and temporal scales is essential to our understanding of the topographic evolution of the *** this work,we quantified millennial-scale erosion rates deduced from cosmogenic^(10)Be and^(26)Al concentrations in 15 fluvial sediments from the mainstream and major tributaries of the Yarlung Zangbo River draining the southern Tibetan Plateau(TP).The measured ratios of^(26)Al/^(10)Be range from 6.33±0.29 to 8.96±0.37,suggesting steady-state erosion *** resulted erosion rates vary from 20.60±1.79 to 154.00±13.60 m Myr-1,being spatially low in the upstream areas of the Gyaca knickpoint and high in the downstream *** examining the relationships between the erosion rate and topographic or climatic indices,we found that both topography and climate play significant roles in the erosion process for basins in the upstream areas of the Gyaca ***,topography dominantly controls the erosion processes in the downstream areas of the Gyaca knickpoint,whereas variations in precipitation have only a second-order *** marginal Himalayas and the Yarlung Zangbo River Basin(YZRB)yielded significantly higher erosion rates than the central plateau,which indicated that the landscape of the central plateau surface is remarkably stable and is being intensively consumed at its boundaries through river headward *** addition,our^(10)Be erosion rates are comparable to present-day hydrologic erosion rates in most cases,suggesting either weak human activities or long-term steady-state erosion in this area.

关键词： in-situ^(10)Be and^(26)Al ^(26)Al/^(10)Be ratio basin-scale erosion topographic and climatic control Yarlung Zangbo River southern Tibet

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Upper mantle convection driving by density anomaly and a test model

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Acta Seismologica Sinica(English Edition) 2005年第1期18卷 27-33,124页

作者：傅容珊王景赟常筱华黄建华戴志阳查显杰 school of earth and Space science University of Science and Technology of China

A mathematic-physical convection model in upper mantle is established in this paper. This model is in a three dimensional frame. Assume that the density anomalies, which are mapped from the seismic tomography data, are responding to the temperature perturbation in the connective system. This model takes the density anomalies as the driving force for the mantle convection. We solve the basic equations with different boundary conditions in a domination of wave number by using the FFT arithmetic. In order to test the validity of our theory and method two simple models (higher-lower density body and break off slab) are employed to calculate their flow patters in this paper. Results show that our method can be directly used to investigate the upper mantle convection patterns and its related problems of lithospheric dynamics.

关键词： mantle convection dynamics seismic tomography

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An automatic unified modeling method of geological object and engineering object based on tri-prism(TP)

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Journal of Central South University 2015年第4期22卷 1419-1426页

作者：张荣春李浩吴铭飞王亚芹 school of earth sciences and engineering Hohai University Department of Water Conservancy Zhejiang Tongji Vocational College of Science and Technology

For the interaction relation between geological object and engineering object in some fields related to water conservancy and hydropower, a unified modeling idea was proposed. On the basis of summarizing both advantages and disadvantages of existing modeling methods, an automatic unified modeling method of both engineering and geological objects based on tri-prism(TP) model was presented. Through the lossless correction algorithm of deviated drill holes contained in this method, the real deviated drill holes could be corrected into the equivalent virtual vertical ones. And the correction accuracy fully meets the requirements of unified modeling. With the virtual vertical drilling data, TIN construction of both cover layer and other stratums would be built in order to obtain the 3D geological model. Then, the engineering design data would be introduced into the 3D geological model for achieving unified modeling. For this process, the volume subdividing and restructuring principles were introduced to deal with the spatial relationships between engineering object and geological object. In order to improve the efficiency of unified modeling, the reconstruction of TIN based on constraint information was also applied in this method. At last, the feasibility and validation of the unified modeling method as well as its relevant key algorithms were verified by specific experiments and analysis of results.

关键词： tri-prism(TP) model unified modeling deviated drill holes correction volume subdividing constraint information

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Volatilization of zinc and lead in direct recycling of stainless steel making dust

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中国有色金属学会会刊：英文版 2004年第2期14卷 392-396页

作者：彭及彭兵余笛唐谟堂 J.Lobel J.A.Kozinski school of Metallurgical science and engineering school of Information science and engineering Department of Metallurgical engineering

The volatilization of zinc and lead from the stainless steel making dust pellets in the direct recycling procedure was conducted by using a thermo-gravimetric analyzer and a Tamman furnace in the nitrogen atmosphere respectively. The results show that the temperature has a significant effect on the volatilization rates of zinc and lead, and the carbon content in the pellets has no effect on the volatilization process. The volatilization of zinc is controlled by the chemical reaction between zinc oxide and carbon monoxide, while the volatilization of lead is controlled by the evaporation from liquid phase to the atmosphere. The volatilization of zinc and lead mainly happen at about 1 000 ℃ according to non-isothermal experiment.

关键词：不锈钢炼钢冶炼烟尘电弧炉 AOD炉 VOD炉

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An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China school of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

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Exotic origin of the Chinese continental shelf: new insights into the tectonic evolution of the western Pacific and eastern China since the Mesozoic

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science Bulletin 2015年第18期60卷 1598-1616页

作者： Yaoling Niu Yi Liu Qiqi Xue Fengli Shao Shuo Chen Meng Duan Pengyuan Guo Hongmei Gong Yan Hu Zhenxing Hu Juanjuan Kong Jiyong Li Jinju Liu Pu Sun Wenli Sun Lei Ye Yuanyuan Xiao Yu Zhang Institute of Oceanology Chinese Academy of Sciences Department of earth sciences Durham University school of earth science and Resources China University of Geosciences Institute of Deep Sea science and engineering Chinese Academy of Sciences school of earth sciences Lanzhou University

The effect of paleo-Pacific subduction on the geological evolution of the western Pacific and continental China is likely complex. Nevertheless, our analysis of the distribution of Mesozoic granitoids in the eastern continental China in space and time has led us to an interesting conclusion： The basement of the continental shelf beneath East and South China Seas may actually be of exotic origin geologically unrelated to the continental lithosphere of eastern China. By accepting the notion that the Jurassic- Cretaceous granitoids in the region are genetically associated with western Pacific subduction and the concept that subduction may cease to continue only if the trench is being jammed, then the termination of the granitoid magmatism throughout the vast region at -88±2 Ma manifests the likelihood of ＂sudden＂, or shortly beforehand （- 100 Ma）, trench jam of the Mesozoic western Pacific subduction. Trench jam happens if the incoming ＂plate＂ or portion of the plate contains a sizeable mass that is too buoyant to subduct. The best candidate for such a buoyant and unsubductable mass is either an oceanic plateau or a micro-continent. We hypothesize that the basement of the Chinese continental shelf represents such an exotic, buoyant and unsubductable mass, rather than seaward extension of the continental lithosphere of eastern China. The locus of the jammed trench （i.e., the suture） is predictably located on the shelf in the vicinity of, and parallel to, the arc-curved coastal line of the southeast continental China. It is not straightforward to locate the locus in the northern section of the East China Sea shelf because of the more recent （〈20 Ma） tectonic re-organization associated with the opening of the Sea of Japan. We predict that the trench jam at - 100 Ma led to the re-orientation of the Pacific plate motion in the course of NNW direction as inferred from the age-progressive Emperor Seamount Chain of Hawaiian hotspot origin （its oldest unsubdued Meiji and Detroi

关键词： Mesozoic granitoids in eastern ChinaExotic origin of Chinese continental shelf Trenchjam Transform plate boundary Basal hydrationweakening Lithosphere thinning Cratondestruction Mantle hydrous melting Crustalmelting Plate tectonics South China Sea

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A Framework for Disaster Vulnerability in a Small Island in the Southwest Pacific: A Case Study of Emae Island, Vanuatu

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International Journal of Disaster Risk science 2017年第4期8卷 358-373页

作者： Guy Jackson Karen McNamara Bradd Witt school of earth and Environmental science The University of Queensland

The societal costs of disasters around the world are continuing to increase and Pacific Island countries are considered some of the most vulnerable. This is primarily due to a combination of high hazard exposure coupled with a range of social, economic, physical, and political vulnerabilities. This article contributes to the growing body of work that aims to understand the causal factors of disaster vulnerability, but with a specific focus on small island developing states. The article first develops a framework for understanding disaster vulnerability, drawing on extensive literature and the well-established Methods for the Improvement of Vulnerability in Europe(MOVE)framework, and second, applies this adapted framework using empirically-derived data from fieldwork on Emae Island, Vanuatu to provide a working understanding of the causal elements of disaster vulnerability. Drawn from a significant body of scholarship at the time, the MOVE framework was primarily developed as a heuristic tool in which disaster vulnerability is considered to be a function of exposure, susceptibility(socially, economically, physically, culturally, environmentally, institutionally), and a lack of resilience. We posit that this adapted framework for small islands should also include historical susceptibility,and we prefer livelihood resilience(as capabilities, social capital, knowledge, participation, and human rights) over lack of resilience. We maintain that understanding disaster vulnerability holistically, which is inclusive of both strengths and drawbacks, is crucial to ensure that limited resources can target the causal factors that produce vulnerability and help safeguard and improve livelihoods in both the short and long term.

关键词： Disaster risk reduction Disaster vulnerability Livelihood resilience Small islands Vanuatu

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