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Magnetic separation of pentlandite from serpentine by selective magnetic coating

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International Journal of Minerals,Metallurgy and Materials 2019年第1期26卷 1-10页

作者： Ji-wei Lu zhi-tao yuan Xiao-fei Guo Zhong-yun Tong Li-xia Li School of Resources and Civil Engineering Northeastern University Shaanxi Key Laboratory for the Comprehensive Utilization of Tailings Resources Shangluo University School of Mining Engineering University of Science and Technology Liaoning

In this study, pentlandite was selectively separated from serpentine using magnetic coating technology by adjusting and optimizing pH, stirring speeds, magnetic field intensities, and dosages of sodium hexametaphosphate(SHMP) and sodium oleate(SO). A magnetic concentrate with Ni grade of 20.8% and Ni recovery of 80.5% was attained under the optimized operating conditions. Considering the above, the adsorption behaviors of SHMP and SO and the surface properties of minerals after the magnetic coating were studied by Fourier transform infrared(FTIR) spectroscopy, X-ray diffraction(XRD), and scanning electron microscopy(SEM). The results show that magnetite was preferentially coated on the pentlandite surfaces and sparingly coated on the serpentine surfaces in the presence of SHMP and SO. Furthermore, calculations by Derjaguin-Landau-Verwey-Overbeek(DLVO) theory indicate that the preferential adsorption of magnetite on the pentlandite surfaces is due to the presence of a hydrophobic interaction between the magnetite and pentlandite, which is much stronger than the interaction between magnetite and serpentine.

关键词： dispersant coagulant magnetic coating magnetic separation hydrophobic interaction

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试论黄鳝嘴文化与大汶口文化的互动

东南文化 2021年第5期 100-111页

作者：陶志远吉林大学考古学院吉林长春130012

黄鳝嘴文化是在考古材料不断丰富的情况下为考古界所确认的新的考古学文化,主要分布于大别山东南麓、长江北岸之间的平原地带。该文化距今约6200—5700年,可分为三个发展阶段:早期以塞墩遗址该文化墓葬早期遗存为代表;中期以黄鳝嘴遗址... 详细信息

黄鳝嘴文化是在考古材料不断丰富的情况下为考古界所确认的新的考古学文化,主要分布于大别山东南麓、长江北岸之间的平原地带。该文化距今约6200—5700年,可分为三个发展阶段:早期以塞墩遗址该文化墓葬早期遗存为代表;中期以黄鳝嘴遗址墓葬遗存为代表;晚期以塞墩遗址该文化墓葬晚期遗存为代表。黄鳝嘴文化与大汶口文化在黄鳝嘴文化早期已然发生过直接或间接联系,可相互之间的影响却较小,但这微弱的互动却是大汶口文化向该地区不断施加影响力的滥觞。

关键词：黄鳝嘴文化分期大汶口文化互动联系

Recent Neutronics Analysis for a China ITER HCSB NT-TBM

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2006年第1期 166-167页

作者： ZHANG Guoshu FENG Kaiming LI Zengqiang CHEN zhi yuan tao

1 Description of structure, materials and MCNP model Except that height, sub-module numbers of present HCSB TBM increases by 2 times, there are hardly other changes in structure and geometry. Fig.l shows general schematic for 3-D structure of previous 3 X 3 and updated 3 X 6 HCSB TBM structure. Present 3X6 HCSB TBM box is mounted on 1/2 ITER testing port. It is 48.4 cm in width, 66 cm in height, 63 cm in depth, 2 cm of gaps on side faces between frame wall and TBM box. A frame wall thickness around TBM module is 20 cm.

关键词：中子物理学他气冷式固体模式核物理核技术

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岩溶地区隧道浅埋段下穿既有构筑物处理技术

铁道工程学报 2018年第2期35卷 51-55,78页

作者：刘志韬郑杰元中铁二院工程集团有限责任公司成都610031

研究目的:随着高速铁路发展,路网密度增加,铁路选线不可避免会下穿高速公路、地方道路或厂房、民房等不可拆除的地表构筑物。当岩溶发育地区铁路采用隧道形式下穿通过既有构筑物时,可能会揭穿隧道范围内的溶腔或岩溶管道,造成充填物流... 详细信息

研究目的:随着高速铁路发展,路网密度增加,铁路选线不可避免会下穿高速公路、地方道路或厂房、民房等不可拆除的地表构筑物。当岩溶发育地区铁路采用隧道形式下穿通过既有构筑物时,可能会揭穿隧道范围内的溶腔或岩溶管道,造成充填物流失或松动,给地表构筑物带来潜在性危害,进而可能影响生产、生活安全。本文结合成贵铁路大方隧道建设情况,就岩溶地区隧道浅埋段下穿既有构筑物隧道施工方法进行研究,提出能够用于未来类似工程的相关理论依据,以有效降低施工过程中对既有构筑物结构安全的影响,确保既有构筑物的使用功能及结构安全。研究结论:(1)应采取措施避免隧道影响范围的溶腔或岩溶管道内充填物流失或松动;(2)需考虑隧道开挖振动及洞内变形对地表构筑物的影响,采用合理的施工开挖方法;(3)加强与构筑物产权单位的协调沟通,确定构筑物防护要求,采取措施确保隧道施工安全和构筑物安全;(4)本研究结论对岩溶地区类似工程条件下隧道设计和施工具有一定的借鉴意义。

关键词：岩溶地区隧道浅埋防护措施处理技术安全

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北阴阳营文化的相关问题

东南文化 2024年第5期 81-93页

作者：段天璟陶志远吉林大学考古学院

分析北阴阳营文化的内涵，可知北阴阳营第一、三、四期遗存均不属北阴阳营文化，北阴阳营文化应以北阴阳营二期遗存为代表，包括釜形鼎、罐形鼎、盆形鼎、侧装把手盉、豆、罐、碗、匜、钵、盆、壶等。北阴阳营文化可分为三期。盉的有无... 详细信息

分析北阴阳营文化的内涵，可知北阴阳营第一、三、四期遗存均不属北阴阳营文化，北阴阳营文化应以北阴阳营二期遗存为代表，包括釜形鼎、罐形鼎、盆形鼎、侧装把手盉、豆、罐、碗、匜、钵、盆、壶等。北阴阳营文化可分为三期。盉的有无是区分北阴阳营文化和黄鳝嘴文化的重要标志。北阴阳营文化一直受到黄鳝嘴文化影响。至北阴阳营文化晚期时，北阴阳营文化向黄鳝嘴文化输出了文化因素，与其展开了互动。

关键词：北阴阳营文化文化内涵分期黄鳝嘴文化

Preliminary Design of ITER TBM with Helium-Cooled and Solid Breeder Concept

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2005年第1期 87-89页

作者： FENG Kaiming ZHANG Guoshu WANG Xiaoyu CHEN zhi yuan tao ZHAO Zhou LI Zengqiang GAO Chunming HU Gang

ITER will play a very important role in first integrated blanket testing in fusion environment. Some DEMO blanket relevant technologies, such as tritium self-sufficiency, extraction of high-grade heat, design criteria... 详细信息

关键词： ITER TBM Tritium breeder

A novel stepwise thresholding for fuzzy image segmentation

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Chinese Journal of Biomedical Engineering(English Edition) 2001年第1期10卷 1-12页

作者： HE Xiao-hai, LUO Dai-sheng, WU Xiao-qiang, JIANG Li, TENG Qi-zhi, tao De-yuan Institute of Electronics and Information, Sichuan University, Chengdu 61064, China Institute of Electronics and Information Sichuan University Chengdu 61064 China

A novel stepwise thresholding method for fuzzy image segmentation is proposed. Unlike the published iterative or recursive thresholding mehtods, this method segments regions into sub-regions iteratively by increasing threshold value in a stepwise manner, based on a preset intensity homogeneity criteria. The method is particularly suited to segmentation of the laser scanning confocal microscopy (LSCM) images, computerised tomography (CT) images, magnetic resonance (MR) images, fingerprint images, etc. The method has been tested on some typical fuzzy image data sets. In this paper, the novel stepwise thresholding is first addressed. Next a new method of region labelling for region extraction is introduced. Then the design of intensity homogeneity segmentation criteria is presented. Some examples of the experiment results of fuzzy image segmentation by the method are given at the end.

关键词： fuzzy image, image processing, image segmentation, iterative thresholding, region labelling, intensity homogeneity

Enhancement of pentlandite surface magnetism and implications for its separation from serpentine via magnetic separation

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Transactions of Nonferrous Metals Society of China 2017年第1期27卷 204-210页

作者：袁致涛卢冀伟刘炯天李丽匣王双玉东北大学资源与土木工程学院沈阳110819 郑州大学化工与能源学院郑州450001

The magnetism of pentlandite surface was enhanced through the selective precipitation of micro-fine magnetite fractions on pentlandite surfaces. This was achieved through adjustment of slurry pH and addition of surfactants. The results showed that at pH 8.8 with the addition of 100 g/t sodium hexametaphosphate, 4.5 L/t oleic acid, and 4.5 L/t kerosene, significant amount of fine magnetite particles adhered to the pentlandite surface, while trace amount of coating was found on serpentine surfaces. Thus, the magnetism of pentlandite was enhanced and pentlandite was well separated from serpentine by magnetic separation under the magnetic field intensity of 200 kA/m. Scanning electron microscopy （SEM） and zeta potential measurement were performed to characterize changes of mineral surface properties. Calculations of the extended Derjaguin-Landau-Verwey-Ocerbeek （EDLVO） theory indicated that, in the presence of surfactants the total interaction energy between magnetite and pentlandite became stronger than that between magnetite and serpentine. This enabled the selective adhesion of magnetite particles to pentlandite surfaces, thereby enhancing its magnetism.

关键词： pentlandite serpentine micro-fine magnetite magnetic separation selective magnetic coating

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加压塔再沸器失效分析与整改方案

压力容器 2008年第1期25卷 56-58页

作者：任军平张克锋陶志远山东华鲁恒升化工股份有限公司山东德州253024

从设计和操作原因对加压塔再沸器管束断裂失效进行分析,并提出改造方案,对换热器的设计使用有一定的借鉴作用。

关键词：管束无支承跨距泄漏