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POA理论下电气技术专业课程思政教学改革与实践

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时代汽车 2024年第18期 23-25页

作者：张博文李瑞锋马海彦陈艳黄颖陕西机电职业技术学院陕西宝鸡721000

随着课程改革的不断推进,思政进课堂已经成为必然趋势,电气技术专业作为当下就业前景较好的工科专业,成为不少学生的选择。通过POA理论体系,系统化地将专业学习与思政课程的融合,以提高学生的综合能力及树立正确的价值观。

关键词： POA理论体系电气技术专业课程思政

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花粉辅助合成钴蓝中空微球及性能研究

黄山学院学报 2024年第3期26卷 43-47页

作者：吴甜甜李瑞锋毕海莲梁培冉陈海龙黄山学院化学化工学院安徽黄山245041

采用荷花花粉辅助共沉淀法制备球状氢氧化物/花粉前驱体,再经高温烧结制得中空微球钴蓝粉末样品。通过调节反应体系的pH值,探讨制备中空微球钴蓝结构的工艺条件。进一步对钴蓝样品进行表征,并提出中空微球钴蓝形成机理。结果表明:pH值... 详细信息

采用荷花花粉辅助共沉淀法制备球状氢氧化物/花粉前驱体,再经高温烧结制得中空微球钴蓝粉末样品。通过调节反应体系的pH值,探讨制备中空微球钴蓝结构的工艺条件。进一步对钴蓝样品进行表征,并提出中空微球钴蓝形成机理。结果表明:pH值对钴蓝的微观形貌及性能影响较大。当pH值为8.5时,制得形貌可控的中空微球钴蓝样品,微球层内存在二级多孔结构,样品的比表面积和比表面能增加,有助于提高光学性能。其呈色性能较优(L*=40.86,a*=-9.81,b*=-39.26),荷花花粉模板在蓝紫光区450—490 nm波段的反射率比未加花粉模板高出约13%,通过对无机钴蓝颜料性能研究将为化学材料的制备提供新方法。

关键词：钴蓝无机颜料荷花花粉反射率中空微球

Zirconium-containing UiO-66 as an efficient and reusable catalyst for transesterification of triglyceride with methanol

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Journal of Energy Chemistry 2016年第5期25卷 874-879页

作者： Fan Zhou Ningyue Lu Binbin Fan Huigang Wang ruifeng li College of Chemistry and Chemical Engineering Taiyuan University of Technology Key Laboratory of Coal Science and Technology MOE Taiyuan University of Technology

Zirconium-based MOFs of the UiO family have attracted considerable attention due to their high thermal,chemical and mechanical stability. With the aim of further exploring the applications of zirconium-based UiO-66 in acid-catalyzed reactions and elucidating the effects of the defects in UiO-66 materials on their catalytic performances, in this work, a series of zirconium-containing UiO-66 samples were synthesized by varying the synthesis temperatures and BDC/Zr(terephthalic acid/ZrCl) ratios in the synthesis *** synthesized UiO-66 samples were characterized by X-ray diffraction(XRD), Nadsorption-desorption,scanning electron microscopy(SEM), thermogravimetrical analysis(TGA), temperature-programmed desorption of NH(NH-TPD). Their catalytic performances were investigated in transesterification of tributyrin and soybean oil with methanol. The results showed that UiO-66 samples with different amounts of defects could be successfully prepared by varying the synthesis temperatures and/or the BDC/Zr ratios used in the synthesis system. The catalytic activities of the UiO-66 materials greatly depended on their linker defects and enhanced with the increase of the defect amount. The UiO-66 was an efficient catalyst for transesterification of tributyrin and soybean oil with methanol under mild reaction conditions and its catalytic activity was comparable to other solid acid catalysts reported in the literatures. The UiO-66 catalyst was relatively stable and could be reused.

关键词： Metal organic frameworks Solid acid Transesterification UiO-66 Catalyst

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卫星重力加速度计标校方法研究

遥感学报 2018年第S1期22卷 114-119页

作者：李瑞锋中国天绘卫星中心北京102102

重力卫星搭载的加速度计用于测量非保守力。加速度计的偏差和标度因数在空间随环境变化而缓慢变化,需要实施外部标定,以方便正确应用于数据处理。很多文献研究了动力学标定法、定轨标定方法、能量标定法等,在快速性、高精度性等方面有... 详细信息

重力卫星搭载的加速度计用于测量非保守力。加速度计的偏差和标度因数在空间随环境变化而缓慢变化,需要实施外部标定,以方便正确应用于数据处理。很多文献研究了动力学标定法、定轨标定方法、能量标定法等,在快速性、高精度性等方面有待提高。本文提出了加速度标定方法,建立数学模型,用于重力卫星的加速度计标定。结果表明,该方法是一种有效的标定方法,在目前的数据条件下,其标校达到10-8—10-9 m/s2水平,标校效果X方向参数最优,Z轴次之,Y轴最差。加速度标校法受到先验地球重力场模型的影响,需要采用迭代方法,逐步逼近真实的加速度计参数。如果提高GNSS轨高产品采样率,可提高总加速度计算精度,从而提高加速度计的定标精度。加速度标定方法是一种有效、快速、精度较高的标定方法,提供精确的标定参数,可以在重力卫星数据处理中使用。

关键词：重力卫星加速度计定标加速度标校法

基于供需视角的中医院非医专业人才需求与就业质量提升策略

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卫生职业教育 2024年第19期42卷 143-147页

作者：张凯旋程歆然王鸿蕴李瑞锋王若佳北京中医药大学管理学院北京102401

目的调查中医院非医专业人才供需现状及现存问题,提出具有针对性的就业质量提升策略。方法对中医药院校非医专业在校生和毕业生进行问卷调查,从人才供给角度探讨其就业认知和满意度,从岗位数量、岗位职能、岗位要求分析中医院对非医专... 详细信息

目的调查中医院非医专业人才供需现状及现存问题,提出具有针对性的就业质量提升策略。方法对中医药院校非医专业在校生和毕业生进行问卷调查,从人才供给角度探讨其就业认知和满意度,从岗位数量、岗位职能、岗位要求分析中医院对非医专业人才的需求。结果非医专业人才培养方案与岗位需求不匹配,中医药院校对社会需求调研不足,非医专业人才就业竞争激烈。从岗位需求情况看,中医院招聘渠道单一,对非医专业人才的需求总体较少,相关岗位更关注非医专业人才学历和工作经验。结论高校和中医院作为供需双方应凝聚合力,供方要从需求角度出发深入了解非医专业人才市场需求情况,及时完善专业人才培养计划;需方要提高对非医专业人才的重视程度,拓宽招聘渠道,建设多元招聘信息传递平台,优化中医院内部科室职能设置。

关键词：中医院非医专业人才需求就业质量

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两步晶化合成ZSM-22分子筛及其临氢异构反应性能

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化工学报 2024年第9期75卷 3176-3187页

作者：王树振王玉婷马梦茜张巍向江南鲁海莹王琰范彬彬郑家军代卫炯李瑞丰太原理工大学化学工程与技术学院山西太原030024

采用两步晶化法,通过调节加入铝源的时间合成了一系列ZSM-22分子筛,并对其酸性位点的分布进行调控。采用XRD、SEM、N2吸附/脱附、NH3-TPD、FTIR、Py-IR、ICP、TEM-EDS等表征方法对其物相、形貌、织构性质、酸性和元素进行表征分析。结... 详细信息

采用两步晶化法,通过调节加入铝源的时间合成了一系列ZSM-22分子筛,并对其酸性位点的分布进行调控。采用XRD、SEM、N2吸附/脱附、NH3-TPD、FTIR、Py-IR、ICP、TEM-EDS等表征方法对其物相、形貌、织构性质、酸性和元素进行表征分析。结果表明,第二步晶化时,加入铝源,在模板剂诱导作用下,促使第一步晶化后高硅ZSM-22表面未晶化的无定形硅酸盐原位合成了ZSM-22分子筛,使高硅ZSM-22表面生长一层低硅铝比ZSM-22分子筛,从而使分子筛的酸性位点发生改变。制备了Pt负载双功能催化剂,研究其正十二烷的临氢异构化反应性能。结果表明,两步晶化ZSM-22分子筛可以抑制微孔内的裂化反应,获得更高异构产物选择性,其中S6-C在330℃时,转化率为89.3%,选择性89.4%,产率79.8%。通过两步晶化方式合成的ZSM-22分子筛,活性位点更多地位于分子筛的外表面和孔口附近,进而改变其异构体产物的分布,降低支链位于碳链端位异构体的比例,更倾向于生成支链位于碳链中间位置的异构体,S12-C的2-甲基十一烷分布比例比常规ZSM-22降低10%左右。

关键词：分子筛催化剂两步晶化临氢异构化正十二烷

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Decomposition of monazite in Bayan Obo rare earth ore by roasting of Na2CO3 pellets

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Journal of Rare Earths 2024年第10期42卷 1969-1978页

作者： ruifeng Ma Jianfei li Xiaowei Zhang Peijie Jia Zhaogang liu Jinxiu Wu Fushan Feng Wenbin Xin College of Materials and Metallurgy Inner Mongolia University of Science and Technology Key Laboratory of Green Extraction and Efficient Utilization of light Rare Earth Resources Ministry of Education Key Laboratory of Rare Earth Wet Metallurgy and light Rare Earth Applications of Inner Mongolia Autonomous Region

To resolve the issue of rotary kiln agglomeration during the sodium carbonate roasting of dolomite rare earth ore,this study introduces an oxidation-sodization pellet roasting method for decomposing mixed rare earth *** focus of this paper lies in understanding the bonding and roasting mechanism of sodium polyacrylate as a binder to dolomite ore and examining the process index of Na2CO3pellets roasting-acid leaching using X-ray diffraction（XRD）,scanning ele ctron microscopy with energy dispersive spectroscopy（SEM-EDS）,and zeta potential analysis,The results indicate that sodium polyacrylate facilitates the bonding of sodium carbonate to monazite via adsorption of positive and negative charges,and upon roasting at 750℃ for 1.5 h to obtain rare earth *** conditions of a hydrochloric acid（HCl） concentration of 9 mol/L,a reaction for 60 min,a solid-to-liquid ratio（g:mL） of 1:5,and reaction temperature of 90℃,the leaching rates of rare earth elements and thorium（Th） reached maxima of 85.14% and 95.53%,*** process results in a yield of 47.61% for fluorine（F） and89.25% for phosphorus（P）.This research forms a foundation for the sodium carbonate roasting decomposition of mixed rare earth concentrates.

关键词： Bayan Obo Decomposition Extraction Pellets Rare earths

Neural Network Based Multi-level Fuzzy Evaluation Model for Mechanical Kinematic Scheme

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武汉理工大学学报 2006年第S1期28卷 301-306页

作者： BO ruifeng,li Ruiqin (Department of Mechanical Engineering,North University of China,Taiyuan 030051,China) Department of Mechanical Engineering North University of ChinaTaiyuan 030051China

To implement a quantificational evaluation for mechanical kinematic scheme more effectively,a multi-level and multi-objective evaluation model is presented using neural network and fuzzy theory. Firstly,the structure of evaluation model is constructed according to evaluation indicator system. Then evaluation samples are generated and provided to train this model. Thus it can reflect the relation between attributive value and evaluation result,as well as the weight of evaluation indicator. Once evaluation indicators of each candidate are fuzzily quantified and fed into the trained network model,the corresponding evaluation result is outputted and the best alternative can be selected. Under this model,expert knowledge can be effectively acquired and expressed,and the quantificational evaluation can be implemented for kinematic scheme with multi-level evaluation indicator system. Several key problems on this model are discussed and an illustration has demonstrated that this model is feasible and can be regarded as a new idea for solving kinematic scheme evaluation.

关键词： neural network mechanical kinematic scheme multi-level evaluation model fuzzy

Progress in the preparation and physical properties of two-dimensional Cr-based chalcogenide materials and heterojunctions

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Frontiers of physics 2024年第2期19卷 105-130页

作者： Xiulian Fan ruifeng Xin li li Bo Zhang Cheng li Xilong Zhou Huanzhi Chen Hongyan Zhang Fangping OuYang Yu Zhou School of Physics and Electronics Hunan Key Laboratory of Nanophotonics and DevicesCentral South UniversityChangsha 410083China Jincheng Research Institute of Opto-mechatronics Industry Jincheng 048000China Shanxi Key Laboratory of Advanced Semiconductor Optoelectronic Devices and Integrated Systems Jincheng 048000China School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Two-dimensional transition metal dichalcogenides(TMDs)exhibit promising application prospects in the domains of electronic devices,optoelectronic devices and spintronic devices due to their distinctive energy band structures and spin−orbit coupling ***-based chalcogenides with narrow or even zero bandgap,covering from semiconductors to metallic materials,have considerable potential for wide-band photodetection and two-dimensional ***,the preparation of 2D CrX_(n)(X=S,Se,Te)nanosheets primarily relies on chemical vapor deposition(CVD)and molecule beam epitaxy(MBE),which enable the production of high-quality large-area *** review article focuses on recent progress of 2D Cr-based chalcogenides,including unique crystal structure of the CrX_(n)system,phase-controlled synthesis,and heterojunction ***,a detailed introduction of room-temperature ferromagnetism and electrical/optoelectronic properties of 2D CrXn is ***,this paper summarizes the challenges associated with utilizing 2D Cr-based chalcogenides in preparation strategies,optoelectronics devices,and spintronic devices while providing further insights.

关键词： physical properties two-dimensional materials Cr-based chalcogenide controlled synthesis heterojunction eletronic and optoelectronic devices