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Surface modification of up-conversion luminescence material Na[Y_(0.57)Yb_(0.39)Er_(0.04)]F_4 with hydrosulfide group

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Journal of University of Science and Technology Beijing 2008年第5期15卷 605-610页

作者： Lili Cui huili fan Junping Xiao Xiaowei Xu Dong Su Applied Science School University of Science and Technology Beijing Beijing 100083 China Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Civil ＆ Environment Engineering School University of Science and Technology Beijing Beijing 100083 China

A new method was reported for surface modification of an up-conversion luminescence material with hydrosulfide group. The factors that may influence the surface modification,such as reaction time,amount of catalyzer and modifier,and reaction solvent,were investigated. The optimal conditions were that the reaction time,the quantity of the basic catalyzer,the quantity of modifier and the volume of reaction solvent were 40 min,1.0,1.0,and 40 mL,respectively. The results indicated that hydrosulfide group content modified on the surface of up-conversion luminescence material reached to 0.1430 mmol/g,and this modified up-conversion luminescence material could be widely used in the study of structure of protein and the property of microenvironment.

关键词： upconversation surface modification luminescence material hydrosulfide react condition

Preparation of bunched CeO_(2) and study on microwave absorbing properties with MWCNTs binary composite

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Particuology 2023年第2期73卷 95-102页

作者： Yingjie Guo Xiangrui Song Sihang Ma Yinghe Qi Xiaotao Yuan huili fan School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing100083China

A novel bunched cerium oxide(CeO_(2))was prepared and its binary composite material with multi-walled carbon nanotubes presented an excellent microwave absorbing *** morphology,structure,and absorbing properties of the composite material were *** was found that the minimum reflection loss(RL)of the composite material at 15.79 GHz was−45.7 dB when the thickness was 5.5 *** was worth noting that when the composite material was in the thickness range of 5.0-7.5 mm and the frequency was 11.36-17.77 GHz,the electromagnetic wave RL was<−30 dB,which illustrated that the composite material had a good absorbing effect over a wide thickness *** results of the study contributed to the design and preparation of efficient microwave absorbing materials(MAM)with rare earth oxide composites and their applications,which demonstrated the importance of new composites with special structures in the field of MAM.

关键词： Bunched cerium oxide Microwave absorbing material Multi-walled carbon nanotubes

Decomposition reaction kinetics of Baotou RE concentrate with concentrated sulfuric acid at low temperature

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Rare Metals 2010年第2期29卷 121-125页

作者： WANG Xiuyan LIU Jiemin LI Mei fan huili YANG Qishan Department of Chemistry University of Science and Technology Beijing Beijing 100083 China School of Materials and Metallurgy Inner Mongolia University of Science and Technology Baotou 014110 China

Baotou RE concentrate was decomposed with concentrated sulfuric acid by controlling the roasting temperature below 500℃.Thermogravimetry-differential thermal analysis（TG-DTA） and chemical analytical methods were used to study the thermal decomposition process and the thermal decomposition *** Freeman-Carroll method was applied to analyze the TG-DTA *** activation energy, reaction order, and reaction frequency factor at different stages were *** Satava method was used to deduce the reaction mechanism and the relative reaction rate during the thermal decomposition process.

关键词： roasting rare earths concentrate TG-DTA reaction kinetics

Surface modification of an up-conversion luminescence material by overcoating with SiO_2 and its characterization

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Rare Metals 2007年第3期26卷 276-279页

作者： CUI Lili LIU Jiemin fan huili XU Xiaowei YANG Min XIAO Junping Department of Chemistry University of Science and Technology Beijing Beijing 100083 China Department of Inorganic Nonmetallic Materials University of Science and Technology Beijing Beijing 100083 China

The surface of an up-conversion luminescence material was modified by overcoating with SiOa, which was synthesized from a hydrolysis progress of telraethoxysilane （TEOS） in alkalescent condition. By analyzing the hydrolyzed mechanism of TEOS, it was found that there was not only physical adsorption but also chemical bonding between the up-conversion material and SiO2. At the same time, some adsorption bands at 1100, 475, 950, and 3500 cm^-1 were found by FI-IR, which were the characteristic bands of Si-OH and Si-O-Si. By analyzing the surface elements of the coated material by XPS, it was found that its surface only included Si, O, and C elements, and not F and Y. In the picture of XRD, there was no additional peak after surface modification, suggesting that the silica shell was amorphous. The small peak at 20 = 23° in the X-ray diffraction pattern of the coated material was caused by the amorphous SiO2 shell, and the TEM image also proved that the surface of the material was successfully modified by overcoating with SiO2. The amount of hydroxyls was then increased on the surface of the material, which made it easy to connect with other active groups.

关键词： surface modification SiO2 sol-gel up-conversation luminescence

Comparison study of two aldehyde group finishing agents in surface modification of up-conversion luminescence materials

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Rare Metals 2008年第2期27卷 127-130页

作者： CUI Lili fan huili XIAO Junping XU Xiaowei Department of Chemistry University of Science and Technology Beijing Beijing 100083 China Department of Inorganic Nonmetallic Materials University of Science and Technology Beijing Beijing 100083 China

Surface modification of up-conversion luminescence materials （Na[Y0.57Yb0.39Er0.04]F4 modified by amino groups） by grafting and modifying with aldehyde groups was studied by means of Fourier transform infrared spectroscopy （FTIR）, scanning electron microscopy （SEM）, thermogravimetric analysis （TGA）, and emission spectrum （EM）. The surface modification effect was compared using two different finishhag agents, p-phthalaldehyde and glutaraldehyde. It was found that the surface of up-conversion luminescence materials could be modified by aldehyde groups of the two finishing agents, the systematic dispersibility and the thermostability of the up-conversion luminescence material modified by p-phthalaldehyde were better than those of the material modified by glutaraldehyde, and the luminous intensity of the material modified by p-phthalaldehyde was increased. The AI （the ratio of the suspended segmental quality in the specimen to the total mass of the specimen） of the material modified by p-phthalaldehyde was higher than that of the material modified by glutaraldehyde. It is obviously seen that the embellishment effect of p-phthalaldehyde as a finishing agent was better than that of glutaraldehyde. In addition, the reasons why p-phthalaldehyde is a good finishing agent are also explained.

关键词： luminescence materials up-conversion surface modification luminescence aldehyde groups

A bird nest-like manganese dioxide and its application as electrode in supercapacitors

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Journal of Energy Chemistry 2013年第6期22卷 928-934页

作者： Fen Ran huili fan Lingren Wang Lei Zhao Yongtao Tan Xuanxuan Zhang Lingbin Kong Long Kang State Key Laboratory of Gansu Advanced Non-Ferrous Metal Materials Lanzhou University of Technology Key Laboratory of Non-ferrous Metal Alloys and Processing of Ministry of Education Lanzhou University of Technology

A novel bird nest-like nanostructured MnO2(BNNS-MnO2) was prepared by a facile and cost-effective strategy. Their structures and morphologies were characterized by field emission scanning electron microscopy, transmission electron microscopy and powder X-ray diffraction. Capacitive behaviors were investigated by cyclic voltammetry and galvanostatic charge-discharge. The obtained nano-MnO2 possesses a well designed loose-assembled hierarchical nanoarchitecture with an appropriate crystallinity which gives rise to excellent performances as an electrode material for supercapacitors. A maximum specific capacitance of 917 F/g has been obtained at a current density of 5 mA/cm2 in 6 mol/L KOH aqueous solution, and a specific capacitance of 210 F/g has been maintained for 500 cycles. As the low cost of MnSO4 and KCr2O7 and the low reaction temperature, the present method avoids the requirements for complicated operations, time/energy-consuming and expensive reagents, and perhaps is ready for the industrialization of nano-MnO2 production.

关键词： energy storage nanostructured MnO2 supercapacitors electrochemical performance electrode material

“三融合,四突出”教学路径探索——物理化学C课程教学创新

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大学化学 2024年第1期39卷 73-79页

作者：杨威王辉陈飞武袁文霞范慧俐韦美菊北京科技大学化学与生物工程学院北京100083

针对传统课堂的教学“痛点”问题,团队教师以课程思政为主导,以现代信息技术为媒介,优化教学目标,重构教学内容,重塑教学过程,强化互动辩论,完善考评机制,持续改进,探索出“三融合,四突出”的教学创新路径。全面解决课程“痛点”问题,... 详细信息

针对传统课堂的教学“痛点”问题,团队教师以课程思政为主导,以现代信息技术为媒介,优化教学目标,重构教学内容,重塑教学过程,强化互动辩论,完善考评机制,持续改进,探索出“三融合,四突出”的教学创新路径。全面解决课程“痛点”问题,全力打造“两性一度”金课,促进学生创新能力和综合素质的提升。

关键词：物理化学教学改革人才培养

Effect of Preparation Condition on Low-density PS Particle Size and Distribution

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Journal of University of Science and Technology Beijing 2001年第4期8卷 274-276页

作者： huili fan, Jiemin Liu, Meijuan Wen, Weixue Tian Applied Science School. University of Science and Technology Beijing.Beijing 100083. China Applied Science School University of Science and Technology Beijing Beijing 100083 China

The preparation conditions were studied in order to obtain smaller, narrow size-distributed and low-density polystyrene (PS) micro-particles by suspension polymerization. The results show that some of preparation conditions, the shape and position of stirrers, and stirring rate etc., have important influence on the size and distribution of particles. The preparation conditions must be carefully designed and controlled in order to obtain high-quality PS beads. A bow-shaped stirrer is helpful to produce small-sized particles and narrow size distribution, and the upper edge of a stirrer should be set to the same level as the surface of mixture, and the stirring rate should be controlled in the range of 520-600 r/min.

关键词： low-density micro-particles suspension polymerization preparation conditions

A hierarchical porous carbon membrane from polyacrylonitrile/polyvinylpyrrolidone blending membranes: Preparation,characterization and electrochemical capacitive performance

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Journal of Energy Chemistry 2014年第6期23卷 684-693页

作者： huili fan Fen Ran Xuanxuan Zhang Haiming Song Wenxia Jing Kuiwen Shen Lingbin Kong Long Kang School of Materials Science and Engineering Lanzhou University of Technology State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of Technology

Novel hierarchical porous carbon membranes were fabricated through a simple carbonization procedure of well-defined blending polymer membrane precursors containing the source of carbon polyacrylonitrile （PAN） and an additive of polyvinylpyrrolidone （PVP）, which was prepared using phase inversion method. The as-fabricated materials were further used as the active electrode materials for supercapacitors. The effects of PVP concentration in the casting solution on structure feature and electrochemical capacitive performance of the as-prepared carbon membranes were also studied in detail. As the electrode material for supercapacitor, a high specific capacitance of 278.0 F/g could be attained at a current of 5 mA/cm2 and about 92.90% capacity retention could be maintained after 2000 charge/discharge cycles in 2 mol/L KOH solution with a PVP concentration of 0.3 wt% in the casting solution. The facile hierarchical pore structure preparation method and the good electrochemical capacitive performance make the prepared carbon membrane particularly promising for use in supercapacitor.

关键词： porous carbon supercapacitors phase separation electrode materials additive