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Preparation and Performance of Ternary Early Strength Agent and Quercetin composite cement Sealing Material

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Journal of Wuhan University of Technology(Materials Sc.ence) 2025年第1期40卷 130-140页

作者： LIU Jian c.en Meiting JI Xiaoli xu chao WANG chunmei Department of Safety Sc.ence and engineering Anhui University of Science and TechnologyHuainan 232001China Key Laboratory of Mine Safety and High Effic.ent Mining Jointly Built by Province and Education Ministry Anhui University of Science and TechnologyHuainan 232001China Department of chemical engineering and Explosives Anhui University of Science and TechnologyHuainan 232001China

A ternary early-strengthening agent consisting of calcium formate+triethanolamine+lithium sulfate was compounded with quercetin to shorten the setting time of cementitious materials while ensuring their early *** optimum ratio of the three early-strengthening agents was determined as 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate by response surface *** effects of the ternary early-strengthening agent composed of calcium formate+triethanolamine(TEA)+lithium sulfate on cementitious pore sealing materials under the synergistic effect of quercetin were studied by means of the performance tests of compressive strength,fluidity,and setting time,and the microstructural characterizations of X-ray powder diffractometer(XRD),thermogravimetry(TG-DSc)and scanning electron microscopy(SEM).The study shows that the synergistic effect of ternary early-strengthening agent and quercetin forms a multi-performance composite admixture for cementitious *** best performance was obtained with the compounding scheme of 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate ternary early-strengthening agent and 0.05%*** compressive strength of 1,3,7,and 28 d are 94.8%,39.8%,42%,and 28%higher than those of the blank group,*** initial time and final setting time are 41 and 57 minutes,*** to the microscopic analysis,the network and fibrous c-S-H gels generated by ternary early-strengthening agents are attached to the surface promoted by quercetin,which forms skeleton support while thic.ening and solidifying the cement slurry,which enhances the early compressive strength of the cement-based materials.

关键词： sealing material ternary early-strengthening agent quercetin synergetic effect response surface methodology

enantio-divergent c–H borylation with two different ligands from a single chiral source

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Sc.ence china chemistry 2025年第1期 226-232页

作者： Rongrong Du Senmiao xu State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences college of Material chemistry and chemical engineering Key Laboratory of Organosilicon Chemistry and Material TechnologyMinistry of Education Hangzhou Normal University University of chinese Academy of Sc.ences

Reported here is an iridium-catalyzed enantio-divergent c（sp3）–H borylation of α-gem-dimethyl groups of trifluoromethyl ketone-derived hydrazones to construct a series of acyclic all-carbon quaternary stereocenters with a high level of chiral induction. Two different chiral bidentate boryl ligands from a common chiral source not only can switch the enantioselectivity but also are complementary in terms of the substrate scope.

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copper-catalyzed c–H bond functionalization enabled by programmed alternating current

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Sc.ence china chemistry 2025年第1期 10-11页

作者： Zhoumei Tan Kun xu c.engchu Zeng Beijing Key Laboratory of environmental and Viral Oncology College of Chemistry and Life Science Beijing University of Technology

Synthetic electrochemistry has been selected as one of the Top Ten Emerging Technologies in chemistry in 2023 by International Union of Pure and Applied chemistry (IUPAc)[1]. It has emerged as a sustainable platform for organic synthesis and has exhibited a wide range of applications from academia to industry [2]. However, electrosynthesis has been predominantly performed by using direct current (Dc).

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Guinier-Preston Zone,Quasicrystal and Long-period Stacking Ordered Structure in Mg-based Alloys,A Review

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Acta Metallurgica Sinica(english Letters) 2013年第3期26卷 217-231页

作者： Yongbo xu Daokui xu Xiaohong SHAO en-hou HAN State Key Laboratory for corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang National Laboratory for Materials Sc.ence

Both the solid solution and precipitation are mainly strengthening mechanism for the magnesium-based alloys. A great number of alloying elements can be dissolved into the Mg matrix to form the solutes and ***, the type of precipitates varies with different alloying elements and heat treatments, which makes it quite difficult to understand the formation mechanism of the precipitates in Mg-based alloys in depth. Thus, it is very hard to give a systematical regularity in precipitation process for the Mg-based alloys. This review is mainly focused on the formation and microstructural evolution of the precipitates, as a hot topic for the past few years, including Guinier-Preston Zones, quasicrystals and long-period stacking ordered phases formed in a number of Mg-TM-RE alloy systems, where TM = Al, Zn, Zr and RE = Y,Gd, Hd, ce and La.

关键词： Guinier-Preston zone Quasicrystal Long-period stacking ordered structure Mg-based alloy

Effect of long-period stacking ordered phase on microstructure,mechanical property and corrosion resistance of Mg alloys: A review

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Progress in Natural Sc.ence:Materials International 2016年第2期26卷 117-128页

作者： Daokui xu en-hou Han Yongbo xu environmental corrosion center Institute of Metal Research Chinese Academy of Sciences Shenyang National Laboratory for Materials Sc.ence

Magnesium alloys containing long period stacking ordered(LPSO) phase have been received a great deal of attention in the last decade owing to their excellent comprehensive properties of mechanical strength and corrosion resistance. In this paper, some fundamental aspects of LPSO containing Mg alloys have been reviewed, including:(1) microstructural characterization, formation conditions and the associated phase transformation of LPSO phases in Mg alloys;(2) deformation mechanism of LPSO phases and their in fl uence on the deformation mechanism of the Mg matrix;(3) effect of LPSO structure on the mechanical performance such as tensile strength, creep resistance, fracture toughness and fatigue strength;(4) corrosion behavior of LPSO containing Mg alloys and their possible applications as the ***, some remaining unsolved issues of the LPSO containing Mg alloys and the future target about how to further improve their service properties have been also described.

关键词： Mg alloys Long-period stacking ordered structure Microstructural characterization Mechanical properties corrosion resistance

On water in nominally anhydrous minerals from mantle peridotites and magmatic rocks

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Sc.ence china Earth Sc.ences 2016年第6期59卷 1157-1172页

作者： HUI HeJiu xu YongJiang PAN Ming'en State Key Laboratory for Ore Deposit Research School of Earth Sciences and Engineering Nanjing University

Trace amount of water associated with the lattice defects of nominally anhydrous minerals （NAMs） can be measured using Fourier transform infrared spectroscopy （FTIR） and secondary ion mass spectrometry （SIMS）. Lots of data on water in NAMs from different lithologies, especially mantle peridotite xenoliths, have been published. The water distribution in olivine from peridotite xenoliths often displays a diffusion profile with high water concentration in the core and low at the rim, which indicates water loss via diffusion during the ascent of host magma. On the other hand, water is homogeneously distributed in pyroxene and its concentration is typically interpreted to represent a mantle value. The water concentration of magma in equilibrium with NAM can be estimated using specific partition coeffic.ent, from which the water content of parental magma and the mantle source can be inferred. The accuracy of this method, however, depends on the selection of appropriate partition coeffic.ent for the system. Using hydrogen isotope compositions and H2O/ce ratios of mantle NAMs, water source regions can be traced and water heterogeneity can be mapped in the upper mantle. Water plays an important role in the stability of cratonic mantle. The water contents and vertical distribution patterns can be significantly different among different cratonic manties, which may result from different geologic activities. However, the mantle-plume interaction may not necessarily result in significant change of water content in cratonic mantle. The estimation of the water content in the upper mantle is still largely based on geochemical models due to the limitations of data on water in mantle NAMs.

关键词： Nominally anhydrous minerals Fourier transform infrared spectroscopy craton stability Water in the upper mantle Magma ascent rate Water in magma

Effect of tannic acid on corrosion behavior of carbon steel in Nacl solution

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Journal of Materials Sc.ence & Technology 2019年第1期35卷 64-75页

作者： Wenhua xu en-Hou Han Zhenyu Wang Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences University of chinese Academy of Sc.ences

corrosion behavior of unrusted Q235 carbon steel was investigated in 3.5% Nacl solutions with 1–5 wt%tannic acid addition, using electrochemical methods including electrochemical impedance spectra(EIS),potentiodynamic polarization and scanning vibrating electrode technique(SVET) combined with surface analysis. Results show that the corrosion rate decreases with increasing tannic acid concentration. As compared with tannic acid-free solution, 1% tannic acid does not provide inhibition effect during the whole immersion, while inhibition effect is observed for 3% tannic acid after 8 h and for 5% tannic acid after 4 h. The inhibition effic.ency by weight loss measurements(áw) for 1%, 3%, and 5% tannic is around-17.2%, 40.3%, and 51.5%, respectively. corrosion of unrusted carbon steel in the presence of tannic acid is attributed to the joint effect of tannic acid adsorption and pH decrease. Formation of ferric-tannates is verified by X-ray photoelectron spectroscopy(XPS) and Raman spectra. The reaction mechanism between tannic acid and unrusted carbon steel is proposed.

关键词： Tannic acid Unrusted carbon steel Ferric-tannates EIS corrosion

Behavior of molten steel flow in continuous casting mold with different static magnetic field configurations

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Journal of Iron and Steel Research International 2018年第4期25卷 366-377页

作者： Zhuang Li en-gang Wang Yu xu Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education) Northeastern University Shenyang 110004 Liaoning China School of Materials Sc.ence and engineering Northeastern University Shenyang 110004 Liaoning China School of Metallurgy Northeastern University Sheuyang 110004 Liaoning China

A three-dimensional mathematical model was established to investigate the behavior of molten steel flow and steel/slag interface with different processes and electromagnetic parameters under two different static magnetic field configurations [ruler-type electromagnetic brake （EMBr ruler） and vertical electromagnetic brake （V-EMBr）] in a continuous casting mold. The results showed that the brake effect of EMBr ruler is significantly influenced by its configuration parameters, the distance between the pole and bottom of the submerged entry nozzle （Sen）, and the port angle of the Sen outlet; therefore, it is not helpful to depress the diffusion of jet flow along the thickness direction of mold. For a constant Sen depth and port angle, there is a reasonable pole position （P = 0 mm） where the pole simultaneously covers three key zones, i.e., the jet flow impact zone and the upward and downward backflow zones. For V-EMBr, the magnetic field can simultaneously cover the three key zones and depress the diffusion of jet flow along the casting and thickness directions of the mold. Both the meniscus height and the impact intensity of the jet flow can be obviously depressed by V-EMBr even if the Sen depth and port angle have changed in the continuous casting process.

关键词： Static magnetic field continuous casting Mold Electromagnetic brake ruler Vertical electromagneticbrake Molten steel flow

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 Zhic.en Wu Liang xu Xinjie Wang Xiaoguang Liu Wanhua Yu Wendong xue School of Materials Sc.ence 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