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Structure and Luminescent Properties of Sm^(3+) Doped SrO-MgO-SiO_2 Glass Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2015年第2期30卷 282-287页

作者：章璐娴何峰 xie junlin LIU Jia School of Materials Science and Engineering Wuhan University of Technology State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology

A new type of samarium ion activated luminescent glass ceramics with main crystal phase of melilite was prepared. The effect of heat-treatment temperature on the structure of glass ceramics was investigated by X-ray diffraction analysis（XRD）, scanning electron microscope（SEM） and fluorescence spectrometer. In the Sm^3＋ doped SrO-MgO-SiO2 glass ceramic, its excitation spectra are in the wavelength range of 350-500 nm, and its excitation peaks are at 360 nm, 374 nm, 404 nm, 417 nm, and 475 nm with the host excitation peak of 404 nm, showing a strong orange-red luminescence when using 404 nm violet to excite it, and its emission peaks are at 564 nm, 600 nm and 648 nm with the host emission peak at 600 nm. The increase in the heat-treatment temperature has no infl uence on the position of the fl uorescent spectra. However, with the increase of heat-treatment temperature, the intensity of fl uorescence spectrum shows an increasing tendency. The increase in the concentration of Sm3＋ also improves the intensity of the fl uorescent spectra. In the experimental concentration range（0.05mol%-0.30mol%）, a special concentration quenching phenomenon happens.

关键词： glass ceramics rare earth luminescence

Effect of Aluminum Addition on Microstructure and Properties of SiO_2-B_2O_3-Al_2O_3-CaO Vitrified Bond

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Journal of Wuhan University of Technology(Materials Science) 2016年第6期31卷 1267-1271页

作者：何峰 ZHANG Wentao ZHOU Qi xie junlin LI Ying State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology Wuhan 430070 China School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 China

Influence of aluminum addition on the structures and properties of SiO_2-B_2O_3-Al_2O_3-CaO vitrified bond at low sintering temperature and high strength was discussed. FTIR and XRD analyses were used to characterize the structures of the basic vitrified bond with different contents of aluminum. The bending strength and the thermal expansion coefficients were also tested. Meanwhile, the microstructures of composite specimens at sintering temperature of 660 ℃ were observed by scanning electron microscope（SEM）. The experimental results showed that the properties of vitrified bond with 1wt% aluminum were improved significantly, where the bending strength, Rockwell hardness, and thermal expansion coefficient of the vitrified bond reached 132 MPa, 63 HRB, and 6.73×10^（-6） ℃^（-1）, respectively.

关键词： vitrified bond aluminum powders structure properties

Effect of Na_(2)O Content on the Structure and Properties of LAS Glass-ceramics Prepared by Spodumene

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Journal of Wuhan University of Technology(Materials Science) 2022年第5期37卷 794-800页

作者： ZHOU Zhiqiang HE Feng SHI Mingjuan xie junlin WAN Peng CAO Dahua School of Materials Science and Engineering Wuhan University of TechnologyWuhan430070China Foshan Shunde Midea Electro-thermal Appliances Manufacturing Co. LtdFoshan528000China

The Li_(2)O-Al_(2)O_(3)-SiO_(2) (LAS) glass-ceramics with low lithium content were prepared from spodumene mineral by melting ***,DSC,and FTIR were used to study the crystallization process and structure of the *** results showed that the addition of Na_(2)O promoted the precipitation of β-quartz solid solution and its transformation to β-spodumene solid *** performance tests and FESEM indicated that the larger grain size and inhomogeneous grain dispersion caused by the increase of Na_(2)O content led to lower mechanical *** addition,low expansion glass-ceramics were prepared by an appropriate heat treatment according to DSC result,and when Na_(2)O content was in the range of 1.22 wt% to 2.41 wt%,the average coefficient of thermal expansion (CTE) (30-300 ℃) increased from-5.810 ×10^(-7 )to 5.322×10^(-7)℃^(-1).

关键词： low thermal expansion Na_(2)O content LAS glass-ceramics spodumene

Calibration of Binding Energy Positions with C1s for XPS Results

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Journal of Wuhan University of Technology(Materials Science) 2020年第4期35卷 711-718页

作者： FANG De HE Feng xie junlin XUE Lihui State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Center for Materials Research and Analysis Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

The adventitious carbon located at 284.8 eV was used to calibrate samples without the carbon *** the carbon is as a major part of the inorganic material,the adventitious carbon should be identified and used as the *** is no adventitious carbon on the surfaces of the polymer materials,so using C1s of the carbon in the polymer itself to calibrate the charging effect is ***,compared with gold and argon,a more practical and convenient method based on C1s is proposed to get the right positions for binding energy peaks.

关键词： XPS calibration charging effect binding energy C1s

Denitrification performance and sulfur resistance mechanism of Sm-Mn catalyst for low temperature NH_(3)-SCR

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Frontiers of Chemical Science and Engineering 2023年第5期17卷 617-633页

作者： junlin xie Yanli Ye Qinglei Li Tianhong Kang Sensheng Hou Qiqi Jin Feng He De Fang State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Center for Materials Research and Analysis Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

MnO_(x)and Sm–Mn catalysts were prepared with the coprecipitation method,and they showed excellent activities and sulfur resistances for the selective catalytic reduction of NO_(x)by NH_(3)between 50 and 300℃in the presence of excess oxygen.0.10Sm–Mn catalyst indicated better catalytic activity and sulfur ***,the Sm doping led to multi-aspect impacts on the phases,morphology structures,gas adsorption,reactions process,and specific surface ***,it significantly enhances the NO conversion,N_(2)selectivity,and sulfur *** on various experimental characterization results,the reaction mechanism of catalysts and the effect of SO_(2)on the reaction process about the catalysts were extensively *** 0.10Sm–Mn catalyst,manganese sulfate and sulfur ammonium cannot be generated broadly under the influence of SO_(2)and the amount of surface adsorbed *** Bronsted acid sites strengthen significantly due to the addition of SO_(2),enhancing the sulfur resistance of the 0.10Sm–Mn catalyst.

关键词： MnO_(x) Sm–Mn catalyst NH_(3)-SCR sulfur resistance

Influence of Nucleating Agent on the Formation of C_4A_3S

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Journal of Wuhan University of Technology(Materials Science) 2012年第1期27卷 177-180页

作者： GUO Huiling xie junlin ZHANG Shu XU Qi Key Laboratory for Silicate Materials Science and Engineering of Ministry of Education Wuhan University of TechnologyWuhan 430070China

The reference test methods are carried out parallelly, by means of chemical analysis, X-ray diffraction, differential scanning calorimetry-thermogravimetry, scanning electron microscopy and polarized optical microscope to study the formation of C4A3S in the presence and absence of nucleating agent. The results show that nucleating agent with high calcium and low heat consumption as tricalcium silicate （C3S） promotes the formation of C4A3S and increases desulfurization degree obviously. During calcining raw meals doped with C3S, the grain sizes of C4A3S are larger compared with that without C3S. And at the same calcining level, the mass loss and the heat consumption belonged to CaCO3 decomposition is reduced.

关键词： desulfurization C4A3S, nucleating agent C3S

Performance enhancement mechanism of Mn-based catalysts prepared under N_2 for NO_x removal:Evidence of the poor crystallization and oxidation of MnO_x

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Chinese Journal of Catalysis 2017年第5期38卷 845-852页

作者： Kai Qi junlin xie De Fang Fengxiang Li Feng He State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology Wuhan 430070 Hubei China Center for Materials Research and Test Wuhan University of Technology Wuhan 430070 Hubei China School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 Hubei China

Among multitudinous metal‐oxide catalysts for the selective catalytic reduction of NOx with NH3(NH3‐SCR),Mn‐based catalysts have become very popular and developed rapidly in recent years because of its superior low‐temperature denitrification activity,mainly originating from multi‐valence of *** studies suggest that the catalytic activity of multi‐component oxides is superior to that of single‐component catalysts owing to the synergistic effect among the metallic elements in such materials,of which more attentions have been given to Ce as an additive owing to its powerful oxygen storage capacity,redox ability and its ready *** the core of SCR technology,the research points in catalyst development at the present stage of all researchers in countries mainly centralize on the optimization of active components,carriers,calcination temperature,calcination time and temperature‐raising procedure,giving little thought to the effects of the calcination *** the present work,Ce‐modified Mn‐based catalysts were prepared by a simple impregnation *** effects of the calcination atmosphere(N2,air or O2)on the performance of the resulting materials during NH3‐SCR and its causes of the differences were subsequently investigated and characterized using various analytical *** obtained from X‐ray diffraction,thermogravimetry and temperature‐programmed reduction with hydrogen show that calcination under N2reduces both the degree of oxidation and crystallization of the *** electron microscopy also demonstrates that the use of N2inhibits the growth of grains and increases the dispersion of the *** addition,the results of temperature‐programmed desorption with ammonia indicate that catalysts calcined under N2exhibit a greater quantity of acid ***,X‐ray photoelectron spectrometry and activity results demonstrate that MnOx in the lower valence states is more favorable for NH3‐SCR *** conclusion,catalysts calcined

关键词： Mn‐based catalyst Selective catalytic reduction Calcination atmosphere Mn species Oxidation degree Crystallization degree

IR and Raman Spectra Properties of Bi2O3-ZnO-B2O3-BaO Quaternary Glass System

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American Journal of Analytical Chemistry 2014年第16期5卷 1142-1150页

作者： Feng He Zijun He junlin xie Yuhui Li State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology Wuhan China Department of Materials Engineering Monash University Melbourne Australia

Among new low-melting-point glasses, bismuth ate glass is deemed to have the most potential as an environmentally friendly replacement for polluting Pb-containing glasses. Current studies of boro-bismuthate glasses focus on the structural influence of the additional oxide in the context of low-melting-point electronic sealing applications. In this study, the structure of quaternary Bi2O3- ZnO-B2O3-BaO glasses was investigated spectroscopic ally, with Fourier-transform-infrared (FT-IR) and Raman spectra recorded for glasses with different main oxide contents. Signals in the FT-IR are mainly observed around 500 cm﹣1, 720 cm﹣1, 840 cm﹣1, 980 - 1080 cm﹣1, and 1200 - 1500 cm﹣1, while the Raman scattering peaks are located at 130 cm﹣1, 390 cm﹣1, 575 cm﹣1, 920 cm﹣1, and 1250 cm﹣1. The glasses are mainly structured around [BO3] units and the numbers of [BiO6] and [BiO3] units increase with the Bi2O3 content increasing. Concurrently, the FT-IR absorption peaks associated with [BO4] units shift to lower wave numbers, indicating a loosening of the glass structure. However, as the B2O3 content is increased, the numbers of [BO3] and [BO4] units increase, while those of [BiO3] and [BiO6] units decrease, highlighting a densification of the glass structure. ZnO acts as a network modifier in these glasses.

关键词： IR and Raman Spectra Bi2O3-ZnO-B2O3-BaO Quaternary Glass System Structure

Effect of the Cool System on Internal Stress of CaO-Al_2O_3-SiO_2 Glass-ceramic System

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Journal of Wuhan University of Technology(Materials Science) 2007年第4期22卷 760-763页

作者：何峰 Key Laboratory of Silicate Materials Science and Engineering of Ministry of Education(Wuhan University of Technology)

The samples were attained through altering the cooling system of producing glass-ceramics. The X-ray diffraction was used to test the stress value of different samples. The relation of the cooling system and internal stress were also investigated. The experimental results show that the stress of glass-ceramic had a close relation with starting cool temperature. Above 800 ~C, glass-ceramic could be accelerated cooling and did not bring stress. Temperature between 500 ℃ and 800℃ was an important temperature range of the formation of stress in glass-ceramic, in which the glass-ceramic stress would change obviously. Cool system was the key on how to control and eliminate internal stress in order to reduce the destroy of materials crated by internal stress. In addition, glass particles size increase, glass-ceramic stress increase in consequent.

关键词： CaO-Al203-SiO2 system glass-ceramic internal stress cooling system