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A novel method for modeling the phase change of iron ore particles in the cohesive zone of a blast furnace

Particuology 2024年第3期86卷 252-261页

作者： Dianyu E Yingming Wen Jiayun Dan Youyuan Jiang Guangchao Wei jiaxin cui Jiangxi Provincial Key Laboratory for Simulation and Modelling of Particulate Systems Jiangxi University of Science and TechnologyNanchang330013China International Institute for Innovation Jiangxi University of Science and TechnologyNanchang330013China Ironmaking Plant Xiangtan Iron and Steel Corporation of Hunan HualingXiangtan411101China Schoolof Transportation and Vehicle Enginering Shandong University of TechnologyZibo255000China

Cohesive zone plays a vital role in the stable operation of a blast furnace(BF),yet the complex phase change process of iron ore particles in this zone is still not well *** this study,a novel one-dimensional(1D)unsteady phase change model was developed to elucidate the heat transfer and melting mechanisms of iron ore *** model validation,the effects of several key operating parameters(e.g.,particle diameter,gas velocity,initial temperature)on the phase change behavior of iron ore particles were analyzed,and the joint effect of multiple parameters was *** results show that larger-sized iron ore particles possess lower specific surface areas,which in turn reduces their convective heat absorption ***,the distance from the solid-liquid phase interface to the particle surface increases,thereby slowing down the movement of the phase interface and pro-longing the melting duration of the *** the gas velocity and the initial temperature does not have a significant impact on reducing the duration of the complete melting *** the specified conditions,it is observed that increasing the gas velocity by 3-fold and 9-fold results in a reduction of the melting duration by 2.4%and 8.3%,*** the initial temperature of iron ore particles results in a decrease in the core-to-surface temperature difference,a slower heating rate,and a shorter duration to achieve *** the factors affecting the melting process,the particle diameter is found to be the most significant in terms of the liquid phase precipitation,mushy zone thickness,and core-to-surface temperature difference of iron ore particles.

关键词： Blast furnace Iron ore melting Cohesive zone Heat transfer Phase change

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Reciprocal Distance Laplacian Eigenvalue Distribution Based on Graph Parameters

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新疆大学学报（自然科学版中英文） 2024年第5期41卷 562-570页

作者： cui jiaxin MA Xiaoling School of Mathematics and System Sciences Xinjiang UniversityUrumqi Xinjiang 830017China

Let G be a connected graph of order n and m_(RD)^(L)_(G)I denote the number of reciprocal distance Laplacian eigenvaluesof G in an interval *** a given interval I,we mainly present several bounds on m_(RD)^(L)_(G)I in terms of various structuralparameters of the graph G,including vertex-connectivity,independence number and pendant vertices.

关键词： reciprocal distance Laplacian eigenvalue vertex-connectivity independence number pendant vertices

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CO_(2)+O_(2)地浸采铀采区含铀砂岩孔隙演化试验研究

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采矿与安全工程学报 2024年第1期41卷 179-189页

作者：贺桂成张沈平扶海鹰崔佳欣张辉南华大学资源环境与安全工程学院湖南衡阳421001

CO_(2)+O_(2)地浸采铀采区含铀砂岩孔隙结构演化影响了铀矿的高效浸出,已成为制约地浸采铀技术发展的瓶颈。为此,采用自制的CO_(2)+O_(2)地浸采铀试验装置,模拟了某砂岩型铀矿地浸采铀过程;并采用高压压汞仪、CT扫描仪和X射线衍射分析... 详细信息

CO_(2)+O_(2)地浸采铀采区含铀砂岩孔隙结构演化影响了铀矿的高效浸出,已成为制约地浸采铀技术发展的瓶颈。为此,采用自制的CO_(2)+O_(2)地浸采铀试验装置,模拟了某砂岩型铀矿地浸采铀过程;并采用高压压汞仪、CT扫描仪和X射线衍射分析仪等设备表征了含铀砂岩岩芯在试验前后的孔隙演化特征;同时,运用Avizo软件构建了三维数字岩芯及其渗流模型,分析了溶浸液渗流规律。研究结果表明:试验后含铀砂岩岩芯总孔隙度和连通孔隙度与试验前相比分别增加了5.03%和5.53%;且试验后数字岩芯的逐层面孔率分布范围更广、孔喉等效半径和喉道面积急剧增大;试验后岩芯孔隙数量随孔隙配位数增大而减小,但当孔隙配位数C≥4时,试验后孔隙数量与试验前相比成倍数增长,最高达到了试验前的21.63倍,此时岩芯中连通孔隙非常显著,渗透率增大;含铀砂岩岩芯中大孔喉相互连接形成的孔隙网络为溶浸液提供了主要的渗流通道,且溶浸液的渗流速度由岩芯中心沿径向方向呈现出由大变小的规律。研究结果可为后续CO_(2)+O_(2)地浸采铀中分析溶质迁移演化规律提供有意义的参考。

关键词： CO_(2)+O_(2)地浸采铀含铀砂岩孔隙演化数字岩芯渗透率

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全球204个国家地区1990至2019年尘肺病发病率和患病率的趋势分析

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中华劳动卫生职业病杂志 2024年第2期42卷 123-128页

作者：唐侍豪崔佳欣陈育全麦秋苑张晋蔚王致广州市第十二人民医院广州市职业病防治院广州市第十二人民医院职业环境与健康重点实验室广州510620 中山大学公共卫生学院广州510080

目的分析全球尘肺病发病率和患病率的变化趋势,为卫生政策制定提供科学依据。方法于2022年6月,通过全球健康数据交换(GHDx)查询工具(http://***/gbd-results-tool)下载并整理尘肺病发病率和患病率数据。应用年估计变化百分比(EAPC)和年... 详细信息

目的分析全球尘肺病发病率和患病率的变化趋势,为卫生政策制定提供科学依据。方法于2022年6月,通过全球健康数据交换(GHDx)查询工具(http://***/gbd-results-tool)下载并整理尘肺病发病率和患病率数据。应用年估计变化百分比(EAPC)和年龄标化率(ASR)估算1990至2019年尘肺病的趋势变化。基于ASR应用线性回归模型估算EAPC。结果在1990至2019年间,全球尘肺病发病率和患病率的ASR均呈下降趋势,EAPC分别为-0.85%(95%CI:-1.11%~-0.60%)和-0.78%(95%CI:-1.08%~-0.49%)。1990至2019年,不同社会人口指数(SDI)地区尘肺病发病率和患病率均呈下降趋势,高SDI地区尘肺病发病率和患病率下降速度均最快,EAPC分别为-1.46%(95%CI:-1.76%~ -1.15%)和-1.99%(95%CI:-2.44%~-1.53%)。110个国家/地区的尘肺病年龄标化发病率(ASIR)呈上升趋势,伊朗和格鲁吉亚的ASIR呈上升趋势最明显,EAPC分别为5.32%(95%CI:4.43%~6.22%)和4.39%(95%CI:3.81%~4.97%)。125个国家/地区的尘肺病患病率ASR呈上升趋势,伊朗患病率上升速度最快(EAPC=6.40%,95%CI:5.33%~7.49%)。结论 1990至2019年间,全球尘肺病发病趋势有所下降,但一些中低收入国家地区尘肺病负担沉重,需要更有效的策略来预防和减轻尘肺病所带来的负担。

关键词：尘肺病全球疾病负担年估计变化百分比年龄标化率

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STPP-nZVI修复铀污染地下水的性能及机理研究

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铀矿冶 2024年第3期43卷 74-85页

作者：贺桂成崔佳欣张辉张沈平南华大学资源环境与安全工程学院湖南衡阳421001

铀是一种重要的战略资源,同时也是一种具有化学毒性和放射性毒性的重金属元素。目前,对铀矿山地下水中铀的高效修复仍是环境保护和生态安全面临的巨大挑战。采用三聚磷酸钠对纳米零价铁改性,成功制备了三聚磷酸钠改性纳米零价铁(STPP-nZ... 详细信息

铀是一种重要的战略资源,同时也是一种具有化学毒性和放射性毒性的重金属元素。目前,对铀矿山地下水中铀的高效修复仍是环境保护和生态安全面临的巨大挑战。采用三聚磷酸钠对纳米零价铁改性,成功制备了三聚磷酸钠改性纳米零价铁(STPP-nZVI),研究了溶液pH、STPP-nZVI用量、温度、时间、U(Ⅵ)浓度和干扰离子对STPP-nZVI修复地下水中U(Ⅵ)的影响,并采用FTIR、SEM-Mapping和XPS探讨了STPP-nZVI修复铀污染地下水的机理。结果表明,STPP-nZVI适合处理弱酸性和碱性铀污染地下水,在pH=5.0时,STPP-nZVI对U(Ⅵ)的最大吸附量达102.72 mg/g,对U(Ⅵ)的吸附为自发的吸热过程,STPP-nZVI对铀的去除主要归功于吸附和还原作用。STPP-nZVI材料对于处理弱酸性和碱性铀污染地下水具有一定的应用前景。

关键词：纳米零价铁三聚磷酸钠铀地下水地下水修复

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基于Stacking的套损预测方法研究

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计算机与数字工程 2024年第6期52卷 1685-1690页

作者：赵建民张珺博崔佳鑫东北石油大学计算机与信息技术学院大庆163318

根据油气生产过程中的套管损坏影响因素众多、数据复杂等特点,通过数据预处理、随机森林重要性分析等技术对现场数据进行分析与整合,采用特征工程的方法处理缺失值并选取特征参数。针对传统机器学习模型对套损预测不佳的问题,提出采用双... 详细信息

根据油气生产过程中的套管损坏影响因素众多、数据复杂等特点,通过数据预处理、随机森林重要性分析等技术对现场数据进行分析与整合,采用特征工程的方法处理缺失值并选取特征参数。针对传统机器学习模型对套损预测不佳的问题,提出采用双层Stacking模式集成学习预测模型;该模型采用随机森林、支持向量机、梯度提升决策树和K近邻算法为基模型,逻辑回归为元模型,以此构建泛化能力更强的套损预测模型。结果表明,该模型较于单一的机器学习模型准确率与F1值均有提升,该模型最终的准确率达到89.21%。

关键词：集成学习套管损耗套损预测 Stacking模型融合

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A Piezoelectrically Driven Microrobot Using a Novel Monolithic Spatial Parallel Mechanism as Its Hip Joint

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Journal of Bionic Engineering 2024年第2期21卷 803-820页

作者： Guangping Wu Ziyang Wang jiaxin Zhao Feng cui Xinghan Cai National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai Jiao Tong UniversityShanghai200240China Department of Micro-Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai200240China

Inspired by the fast,agile movements of insects,we present a 1.9 g,4.5 cm in length,piezoelectrically driven,quadrupedal *** microrobot uses a novel spatial parallel mechanism as its hip joint,which consists of two spatially orthogonal slider-crank *** mechanism maps two inputs of two independent actuators to the decoupled swing and lift outputs of a leg,and each leg can produce the closed trajectories in the sagittal plane necessary for robot ***,the kinematics of the transmission are analyzed,and the parameters of the flexure hinges are designed based on geometrical constraints and yield *** hip joints,legs and exoskeletons are integrated into a five-layer standard laminate for monolithic fabrication which is composed of two layers of carbon fiber,two layers of acrylic adhesive and a polyimide *** measured output force(15.97 mN)of each leg is enough to carry half of the robot’s weight,which is necessary for the robot to move *** has been proven that the robot can successfully perform forward and turning *** to the microrobot fabricated with discrete components,the monolithically fabricated microrobot is more capable of maintaining the original direction of locomotion when driven by a forward signal and has a greater speed,whose maximum speed is 25.05 cm/s.

关键词： Insect-like Crawling microrobot Piezoelectric drive Parallel mechanism Monolithic fabrication

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Particle shape effect on hydrodynamics and heat transfer in spouted bed:A CFD-DEM study

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Particuology 2022年第10期20卷 10-21页

作者： Dianyu E Peng Zhou Suya Guo Jia Zeng jiaxin cui Youyuan Jiang Yuanxiang Lu Zeyi Jiang Zhengquan Li Shibo Kuang Jiangxi Provincial Key Laboratory for Simulation and Modelling of Particulate Systems Jiangxi University of Science and TechnologyGanzhou 341000China Ironmaking Plant Xiangtan Iron and Steel Corporation of Hunan HualingXiangtan 411101China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China ARC Research Hub for Computational Particle Technology Department of Chemical EngineeringMonash UniversityClaytonVIC 3800Australia

Spouted bed has drawn much attention due to its good heat and mass transfer efficiency in many chemical *** the flow patterns and heat and mass transfer inside a spouted bed can help optimize the spouting ***,in this study,the effects of particle shape on the hydrodynamics and heat transfer in a spouted bed are *** is done by using a validated computational fluid dynamics-discrete element method(CFD-DEM)model,considering volume-equivalent spheres and oblate and prolate *** results are analysed in detail in terms of the flow pattern,microstruc-ture,and heat transfer *** numerical results show that the prolate spheroids(Ar=2.4)form the largest bubble from the beginning of the spouting process and rise the highest because the fluid drag forces can overcome the interlocking and particle-particle frictional *** with spherical particles,ellipsoidal spheroids have better mobility because of the stronger rotational kinetic energy resulting from the rough surfaces and nonuniform *** addition,the oblate spheroid system exhibits better heat transfer performance benefiting from the larger surface area,while prolate spheroids have poor heat transfer efficiency because of their orientation *** findings can serve as a reference for optimizing the design and operation of complex spouted beds.

关键词： Spouted bed Gas-solid flow Particle shape CFD-DEM Heat transfer

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共混改性聚乳酸基薄膜的制备及其包膜肥的缓释性能研究

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生物化工 2024年第2期10卷 83-88页

作者：王聪莹王丽敏石宏岩崔佳欣周赫然赤峰学院资源环境与建筑工程学院内蒙古赤峰024000 赤峰学院化学与生命科学学院内蒙古赤峰024000

以二氯甲烷(DCM)或无水乙醇(EtOH)为溶剂,以聚乳酸(PLA)为原料,通过与聚乙二醇(PEG)、聚丁二酸丁二醇酯(PBS)共混改性制备生物可降解聚合物膜。同时将生物质灰渣与尿素混掺制备球状肥芯,通过高压喷雾包覆10%聚合物膜制备包膜肥颗粒。通... 详细信息

以二氯甲烷(DCM)或无水乙醇(EtOH)为溶剂,以聚乳酸(PLA)为原料,通过与聚乙二醇(PEG)、聚丁二酸丁二醇酯(PBS)共混改性制备生物可降解聚合物膜。同时将生物质灰渣与尿素混掺制备球状肥芯,通过高压喷雾包覆10%聚合物膜制备包膜肥颗粒。通过氮素渗透率测试和静水中肥料颗粒氮素渗透实验确定聚合物膜及包膜肥的尿素释放能力。结果表明,以DCM为溶剂,将PLA和PBS共混制备得到的聚合物膜表面结构致密、力学性能与疏水性相对于PLA膜明显提高;以其制备的包膜肥对氮素溶液的渗透系数小,在第1天和第28天的氮素释放率分别为0.27%和40.05%,缓释周期较长。

关键词：包膜肥缓释肥生物可降解膜

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Effects of Bacillus subtilis and Saccharomyces cerevisiae inoculation on soil bacterial community and rice yield under combined irrigation with reclaimed and fresh water

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International Journal of Agricultural and Biological Engineering 2022年第3期15卷 33-46页

作者： Hongfei Lu Xuebin Qi Ping Li Dongmei Qiao Shafeeq-ur-Rahman Fangfang Bai jiaxin cui Farmland Irrigation Research Institute Chinese Academy of Agricultural SciencesXinxiang 453003HenanChina Water Environment Factor Risk Assessment Laboratory of Agricultural Products Quality and Safety Ministry of Agriculture and Rural AffairsXinxiang 453002HenanChina Agricultural Water Soil Environmental Field Research Station of Xinxiang Chinese Academy of Agricultural SciencesXinxiang 453002HenanChina Jiangsu Vocational College of Agriculture and Forestry Jurong 212499JiangsuChina

In order to save fresh water and reduce soil salt accumulation,reclaimed water-fresh water combined irrigation,i.e,irrigation with reclaimed water for 50 d and then with fresh water till harvest,was used in rice *** subtilis and Saccharomyces cerevisiae were inoculated into the soil at the end of reclaimed water *** inoculation weight per pot of these microorganisms was as follows:0 g and 0 g(J0),5 g and 0 g(J1),3.75 g and 1.25 g(J2),2.5 g and 2.5 g(J3),1.25 g and 3.75 g(J4),and 0 g and 5 g(J5),*** using reclaimed water in the whole stage was used as the control(CK).The plant height,tiller,physical and chemical properties of the soil,and soil bacterial diversity were *** was found that the plant height of rice was increased significantly by J1-J5 *** dry weight of rice root,stem,and panicle and the 1000-grain weight increased significantly,while the leaf dry weight *** inoculation significantly increased the nutrient absorption capacity of the crops.J1,J2,and J4 treatments significantly increased the amount of nitrate-nitrogen,ammonium nitrogen,available phosphorus,and available potassium,while J3,J4,and J5 treatments increased the soil organic matter,and microbial inoculation significantly decreased the EC of soil.J4 treatment induced the largest reduction in EC,and microorganisms treatments increased soil *** function prediction based on the KEGG(Kyoto Encyclopedia of Genes and Genomes)pathway indicated that soil metabolic function was not significantly disturbed by the *** matter and pH are the two main factors affecting the structure of the bacterial community in soil.3.75 g of *** and 1.25 g of *** per pot is the best inoculation ratio.

关键词： Bacillus subtilis Saccharomyces cerevisiae rice reclaimed water soil

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