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Preparation of Co/S co-doped carbon catalysts for excellent methylene blue degradation

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 169-181页

作者： Haixu Li Haobo He Tiannan Jiang Yunfei Du Zhichen Wu Liang Xu Xinjie Wang Xiaoguang Liu Wanhua Yu Wendong Xue School of Materials science and Engineering University of Science and Technology BeijingBeijing 100083China beijing Jinyu Tongda Refractory Technologies Co. Ltd.Beijing 100085China

S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB)*** effects of two different mixing routes were identified on the MB degradation ***,the catalyst obtained by the alcohol solvent evaporation(MOF-AEP)mixing route could degrade 95.60%MB(50 mg/L)within 4 min(degradation rate:K=0.78 min^(-1)),which was faster than that derived from the direct grinding method(MOF-DGP,80.97%,K=0.39 min^(-1)).X-ray photoelectron spectroscopy revealed that the Co-S content of MOF-AEP(43.39at%)was less than that of MOF-DGP(54.73at%),and the proportion of C-S-C in MOF-AEP(13.56at%)was higher than that of MOF-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of Co for PMS was -2.94 eV when sulfur was doped as C-S-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of Co-S bond(-2.86 eV).Thus,the C-S-C sites might provide more contributions to activate PMS compared with ***,the degradation parameters,including pH and MOF-AEP dosage,were ***,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading MB.

关键词： advanced oxidation process alcohol solvent evaporation hydrogen bond S and Co co-doped carbon catalysts wastewater remediation

Nanocrystalline BaTi2O5 dielectric ceramic prepared by full crystallization from containerless solidified glass

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Journal of Advanced Ceramics 2016年第1期5卷 92-页

作者： Jianqiang LI Guoqing BA Xiwei QI Xiaoyu LI Yingcui SONG Bo LI National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of Sciences Beijing 100190 China School of Resources and Materials Northeastern University at Qinhuangdao Qinhuangdao 066004 China National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of Sciences Beijing 100190 ChinaResearch Institute for Advanced Materials Graduate School at ShenzhenTsinghua University Shenzhen 518055 China Research Institute for Advanced Materials Graduate School at ShenzhenTsinghua University Shenzhen 518055 China

We show that fully dense nanocrystalline titanate ceramic could be obtained by full crystallization from glass which was prepared by a novel contactless solidification process. Through annealing above glass transition temperature T g for prescribed duration, BaTi2O5 ceramic with grain size of 20–130 nm was successfully fabricated. The dependence of the nanoceramic’s dielectric constant and dissipation on frequency was investigated. The results show clearly that the dielectric constant of BaTi2O5 nanoceramic depends on average grain size in nanometer scale, and an optimal range of the grain size is found which exhibits greater dielectric constant than conventional microcrystalline ceramics. The as-fabricated ceramic also possesses lower dielectric dissipation, which can be mainly attributed to the presence of nanometer-sized grains.

关键词： nanocrystalline ceramic glass BaTi2O5 containerless solidification dielectric properties

NOVEL HYPERBRANCHED POLY(PHENYLENE OXIDE)S WITH PHENOLIC TERMINAL GROUPS: EFFECTS OF REACTION TIME AND CORE MOLECULES ON THE MOLECULAR WEIGHT AND POLYDISPERSITY

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Chinese Journal of Polymer science 2006年第4期24卷 413-419页

作者：李效玉 The Key Laboratory for Nanomaterials Ministry of Education College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

A novel hyperbranched poly（phenylene oxide）（HPPO） with phenolic terminal groups was prepared from 4-bromo-4＇,4＂-dihydroxytriphenylmethane as AB2 monomer in dimethylsulfoxide （DMSO） via a modified Ullmann reaction. The molecular weight and polydispersity （PD） of the resulting polymers increased with increasing reaction time. In the presence of core molecules （bisphenol A and 1,3,5-trihydroxybenzene）, which have the similar molecular backbones to the reactive monomer, the molecular weight could be controlled by varying the core-to-monomer ratio. Incorporation of a very small amount of core molecules could lead to a higher molecular weight as compared with that without the addition of core molecules. However, when the core content reached certain extent, the molecular weight would decrease with the further increase in the core content. A new similar behavior of control over the PD was also obtained. The resulting polymers were characterized by ^1H-NMR, ^13C-NMR, FT-IR, and GPC.

关键词： Hyperbranched Poly(phenylene oxide) Controlled reaction Core molecule.

INVERSE OPALINE STRUCTURE TITANIA PHOTONIC CRYSTALS BY FUNCTIONALLY MODIFIED COLLOIDAL CRYSTALS TEMPLATING

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Chinese Journal of Polymer science 2007年第2期25卷 217-220页

作者： Hong-yu Li Zhi-qiang Chen Hai-qiao Wang Bo Meng Xiao-yu Li Department of Chemistry Anyang Teachers College Anyang Henan 455000 China The Key Laboratory of Nanomaterials of Ministry of Education College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

Ordered macroporous titania photonic crystals （PCs） and photonic balls were fabricated by functional modified polymer colloidal crystals. The TiO2 PCs and balls formed through this method exhibit no cracks and lacun... 详细信息

关键词： Photonic crystals Photonic balls Ordered macroporous titania Polymer colloidal crystals.

Early-age strength property improvement and stability analysis of unclassified tailing paste backfill materials

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International Journal of Minerals,Metallurgy and Materials 2020年第9期27卷 1191-1202页

作者： Qian Zhou Juan-hong Liu Ai-xiang Wu Hong-jiang Wang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of High-Efficient Mining and Safety of Metal Ministry of EducationUniversity of Science and Technology BeijingBeijing 100083China

High-density tailings,small cementitious materials,and additives are used for backfill materials with poor early compressive strength(ECS),which may greatly affect the mining and backfill cycle,to prepare paste backfill materials(PBMs)with a high *** effects and mechanisms of different early strength agents on the property of PBM are *** action mechanism of additives on the properties of PBM is also analyzed through X-ray diffraction,scanning electron microscope,and energy dispersive *** show that the effects of single-component additives 1,3,and 6 are better than those of the other additives,and their optimal dosages are 3wt%,1wt%,and 3wt%,*** optimum multicomponent combinations are 1wt%of additive 1 and 1.5wt%of additive *** ECS of the paste with additive 10 increases to a greater extent than that of the other pastes because of the synergistic action of additive 1 with additive *** hydration product of Ca(OH)2 is consumed,and more C-S-H gels are generated with the addition of additives to *** particles,ettringite crystals,and gels intertwined with one another form a dense net-like structure that fills the *** structure can significantly improve the ECS of PBM.

关键词： paste backfill unclassified tailings binder powder early-age strength microstructure

Effect of vanadium content on hydrogen storage property in Ti-V-Cr alloys

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Rare Metals 2006年第Z1期25卷 374-377页

作者： SONG Xiping PEI Pei ZHANG Peilong CHEN Guoliang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The effect of vanadium content on the microstructure and hydrogen absorption/desorption properties in Ti-V-Cr alloys was studied. The results show that with the increase of vanadium content from 5at.%, 10at.% to 35at.%, the hydrogen absorption capacity increases gradually from 1.14wt.%, 1.57wt.% to 2.84wt.%, and the hydrogen desorption capacity also increase from 0.43, 0.64, to 1.59. This indicates that the alloy with 35at.% vanadium content has the most optimum hydrogen storage capacity among these alloys. The microstructure observation also indicates that the alloy with 35at.% vanadium turns to be the single-phase alloy of the BCC solid solution. Furthermore, with the increase of vanadium content the pressure plateau becomes more distinguishing and shifts to lower pressure level gradually. The kinetics of hydrogen absorption was also found to be dependent with the vanadium content in these discussed alloys.

关键词： hydrogen storage alloy vanadium kinetics

Influences of interphase on dynamic effective properties of composites reinforced by dispersed spherical particles

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Journal of University of science and Technology beijing 2006年第3期13卷 256-262页

作者： Peijun Wei Lili Gu Applied sciences School University of Sciences and Technology Beijing Beijing 100083 China Tangshan Iron ＆ Steel Group Co. Ltd Tangshan 063016 China

The influences of interphase on dynamic effective properties of composites reinforced by randomly dispersed spherical particles were studied. A thin homogeneous elastic interphase with different shear and bulk moduli, located between the reinforced particle and the host matrix, was introduced to model the interfacial bonding state. The effects of such an interphase on the coherent plane waves were studied numerically. Numerical simulations were carried out for SiC-Al composites with four typical cases of interphase. It was found that the property of interphase has significant influences on the effective propagation constants of coherent waves and the dynamic effective elastic moduli of the composites. The influences on the coherent longitudinal wave and the coherent shear waves were different and dependent upon the frequency range. Moreover, several imperfect interface models, i.e., the spring model, mass model, and spring-mass model, were studied numerically and compared with the interphase model, It was found that the spring model is a more suitable model than the mass model for the light and weak interphase whereas the mass model is a more suitable model than the spring model for the heavy and strong interphase.

关键词： composites effective property coherent wave interface model interphase multiple scattering

Microstructural characteristics and aging response of Zn-containing Al-Mg-Si-Cu alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 659-664页

作者： Yuan-hua Cai Cong Wang Ji-shan Zhang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

Al-Mg-Si-Cu alloys with and without Zn addition were fabricated by conventional ingot metallurgy method. The microstructures and properties were investigated using optical microscopy （OM）, field emission scanning electron microscopy （FE-SEM）, transmission electron microscopy （TEM）, tensile test, hardness test, and electrical conductivity measurement. It is found that the as-cast A1-Mg-Si-Cu-Zn alloy is composed of coarse dendritic grains, long needle-like ~/5-A1FeSi white intermetallics, and Chinese script-like a-A1FeSi compounds. During high temperature homogenization treatment, only harmful needle-like ^-A1FeSi phase undergoes fragmentation and spheroidizing at its tips, and the destruc- tive needle-like 5-phase does not show any morphological and size changes. Phase transitions from ^-A1FeSi to ^-A1FeSi and from 6-A1FeSi to [3-A1FeSi are also not found. Zn addition improves the aging hardening response during the former aging stage and postpones the peak-aged hardness to a long aging time. In T4 condition, Zn addition does not obviously increase the yield strength and decrease the elongation, but it markedly improves paint-bake hardening response during paint-bake cycle. The addition of 0.5wt% Zn can lead to an increment of 99 MPa in yield strength compared with the value of 69 MPa for the alloy without Zn after paint-bake cycle.

关键词： aluminum alloys zinc hardening mechanical properties microstructure

Effects of Sb and heat treatment on the microstructure of Al-15.5wt%Mg_2Si alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 653-658页

作者： Yu-hua Zhao Xiu-bin Wang Xing-hao Du Chao Wang School of Materials science and Engineering Shenyang Aerospace University

The modification effects of alloying element Sb and heat treatment on Al-15.5wt%Mg2Si alloy were investigated by Olympus microscopy （OM）, scanning electron microscopy and energy disperse spectroscopy （SEM-EDS）, and X-ray diffraction （XRD）. It is found that Sb plays a significant role in shaping primary Mg2Si phase and eutectic Mg2Si phase in Al-15.5wt%MgzSi alloy. The Sb addition of about 1.0wt% makes the resultant alloy show the finest primary Mg2Si phase and the eutectic Mg2Si phase with well distribution. But further increasing the Sb content decreases the amount of primary Mg2Si phase, and some segregated phases appear at regions between the grains. In addition, heat treatment can modify the microstructural feature of Sb-modified Al-15.5wt%Mg2Si alloy in terms of obviously shortening the nodulizing time of primary Mg2Si phase and eutectic Mg2Si phase.

关键词： aluminum alloys intermetallics heat treatment antimony microstructure modification