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Deterioration Reason and Improvement Measure of the Retarding Effect of Protein Retarder on Phosphorus Building Gypsum

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Journal of Wuhan University of Technology(materials Science) 2024年第4期39卷 962-967页

作者：刘志刚 TANG Zezheng 杨立荣 WANG Chunmei XIE Yuantao LIU Yisen college of materials Science and engineering North China University of Science and TechnologyTangshan 063210China

The retarding effect of protein retarder on phosphorus building gypsum(PBG)and desulfurization building gypsum(DBG)was investigated,and the results show that protein retarder for DBG can effectively prolong the setting time and displays a better retarding effect,but for PBG shows a poor retarding ***,the deterioration reason of the retarding effect of protein retarder on PBG was investigated by measuring the pH value and the retarder concentration of the liquid phase from vacuum filtration of PBG slurry at different hydration time,and the measure to improve the retarding effect of protein retarding on PBG was *** pH value of PBG slurry(<5.0)is lower than that of DBG slurry(7.8-8.5).After hydration for 5 min,the concentration of retarder in liquid phase of DBG slurry gradually decreases,but in liquid phase of PBG slurry continually increases,which results in the worse retarding effect of protein retarder on *** liquid phase pH value of PBG slurry can be adjusted higher by sodium silicate,which is beneficial to improvement in the retarding effect of the *** adding 1.0%of sodium silicate,the initial setting time of PBG was efficiently prolonged from 17 to 210 min,but little effect on the absolute dry flexural strength was observed.

关键词： protein retarder phosphorus building gypsum deterioration reason improvement measure

Thermodynamic equilibrium theory-guided design and synthesis of Mg-doped LiFe_(0.4)Mn_(0.6)PO_(4)/C cathode for lithium-ion batteries

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Journal of Energy Chemistry 2024年第4期91卷 619-627页

作者： Wei Lyu Wenlong Cai Tuan Wang Xiaobo Sun Enhao Xu Jinxuan Chen Kaipeng Wu Yun Zhang college of materials Science and engineering Sichuan UniversityChengdu 610064SichuanChina

Mn-rich LiFe_(1-x)Mn_(x)PO_(4)(x>0.5),which combines the high operation voltage of LiMnPO_(4)with excellent rate performa nce of LiFePO4,is hindered by its sluggish kinetic ***,thermodynamic equilibrium analysis of Mn^(2+)-Fe^(2+)-Mg^(2+)-C_(2)O_(4)^(2-)-H_(2)O system is used to guide the design and preparation of insitu Mg-doped(Fe_(0.4)Mn_(0.6))_(1-x)Mg_(x)C_(2)O_(4)intermediate,which is then employed as an innovative precursor to synthesize high-performance Mg-doped LiFe_(0.4)Mn_(0.6)PO_(4).It indicates that the metal ions with a high precipitation efficiency and the stoichiometric precursors with uniform element distribution can be achieved under the optimized thermodynamic ***,accelerated Li+diffusivity and reduced charge transfer resistance originating from Mg doping are verified by various kinetic *** from the contributions of inherited homogeneous element distribution,small particle size,uniform carbon layer coating,enhanced Li+migration ability and structural stability induced by Mg doping,the Li(Fe_(0.4)Mn_(0.6))_(0.97)Mg_(0.03)PO_(4)/C exhibits splendid electrochemical performance.

关键词： (Fe_(0.4)Mn_(0.6))_(1-x)MgxC_(2)0_(4) precursors Thermodynami cequilibrium Co-precipitation Mg doping Lithium-ion batteries

Oxidation behavior of FeV_(2)O_(4)and FeCr_(2)O_(4)particles in the air:Nonisothermal kinetic and reaction mechanism

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International Journal of Minerals,Metallurgy and materials 2024年第8期31卷 1839-1848页

作者： Junyi Xiang Xi Lu Luwei Bai Hongru Rao Sheng Liu Qingyun Huang Shengqin Zhang Guishang Pei Xuewei Lü School of Metallurgy and materials engineering Chongqing University of Science and TechnologyChongqing 401331China Department of materials Science and engineering Seoul National UniversitySeoul 08826Rep.of Korea college of materials Science and engineering Chongqing UniversityChongqing 400044China

High-temperature oxidation behavior of ferrovanadium(FeV_(2)O_(4))and ferrochrome(FeCr_(2)O_(4))spinels is crucial for the application of spinel as an energy material,as well as for the clean usage of high-chromium vanadium ***,the nonisothermal oxidation behavior of FeV_(2)O_(4)and FeCr_(2)O_(4)prepared by high-temperature solid-state reaction was examined by thermogravimetry and X-ray diffraction(XRD)at heating rates of 5,10,and 15 K/*** apparent activation energy was determined by the Kissinger-Akahira-Sunose(KAS)method,whereas the mechanism function was elucidated by the Malek ***,in-situ XRD was conducted to deduce the phase transformation of the oxidation mechanism for FeV_(2)O_(4)and FeCr_(2)O_(4).The results reveal a gradual increase in the overall apparent activation energies for FeV_(2)O_(4)and FeCr_(2)O_(4)during *** stages of the oxidation process are observed based on the oxidation conversion rate of each *** oxidation mechanisms of FeV_(2)O_(4)and FeCr_(2)O_(4)are complex and have distinct *** particular,the chemical reaction controls the entire oxidation process for FeV_(2)O_(4),whereas that for FeCr_(2)O_(4)transitions from a three-dimensional diffusion model to a chemical reaction *** to the in-situ XRD results,numerous intermediate products are observed during the oxidation process of both compounds,eventually resulting in the final products FeVO_(4)and V2O_(5)for FeV_(2)O_(4)and Fe_(2)O_(3)and Cr_(2)O_(3)for FeCr_(2)O_(4),respectively.

关键词： FeV_(2)O_(4) FeCr_(2)O_(4) oxidation nonisothermal kinetics mechanism

Investigating the Absorption and Desorption Behavior of Methylene Chloride in the Poly(aryl ether ketone) Film with Different Crystallinities

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Chinese Journal of Polymer Science 2024年第2期42卷 239-246,I0009页

作者： Hong-Ru Yang Jin-Dong Zhang Dong-Ting Gao Gang Liu Chun-Hai Chen Jia-Nan Yao Center for Advanced Low-Dimension materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China

Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different *** to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing *** effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile *** tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced *** scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization *** results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.

关键词： Poly(aryl ether ketone) Diffusion behavior Infrared spectra Solvent-induced crystallization Mechanical properties

π-conjugated chromophore functionalized high-nuclearity titanium-oxo clusters containing structural unit of anatase for photocatalytic selective oxidation of sulfides

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Rare Metals 2024年第4期43卷 1736-1746页

作者： Ling-Rong Liao Dong-Chun Zheng Pin-Xi Ou Qi-Xin Zhao Wei-Min Xuan Qi Zheng State Key Laboratory for Modification of Chemical Fibers and Polymer materials&college of materials Science and engineering Donghua UniversityShanghai201620China State Key Laboratory for Modification of Chemical Fibers and Polymer materials and college of Chemistry and Chemical engineering Donghua UniversityShanghai 201620China

N-doping has significant influence in manipulating the properties of TiO_(2),and this has stimulated the development of N-donor-functionalized titanium-oxo clusters(TOCs)as molecular models to study the structure-property ***,the structural type and photoresponsive application are still limited for such TOCs,especially regarding the high-nuclearity TOCs that contain structure unit of TiO_(2)for ***,we showed the synthesis of a series of high-nuclearity TOCs 1-3 compounds usingπ-conjugated 1,10-phenanthroline(phen)as chromophore and N-donor functional *** 1 features cocrystal structure composed of one[Ti_(26)]~(2+)and half[Ti_(22)]~(2+),which renders it as the first cocrystallized TOC containing two positively charged species and phen-functionalized TOC showing the highest nuclearity up to 37 Ti *** adjusting the synthetic conditions,the individual{Ti_(22)}and{Ti_(26)}clusters can also be isolated as Compounds 2 and 3,*** core structure of{Ti_(22)}is mainly constructed from four lacunary{Ti_(4)}derived from pentagonal{Ti(Ti)_5}unit,while{Ti_(26)}is built from four complete{Ti(Ti)_5}***,a{Ti_8O_(14)}structure unit of anatase TiO_(2)can be identified in{Ti_(26)}.Based on the unique structural features and proper photophysical and photochemical properties of Compounds 1-3,they are applied for photocatalytic *** to the presence of anatase structure unit in{Ti_(26)}and the synergistic effect from{Ti_(22)}and{Ti_(26)},the catalytic performance presents in the order of Compound 1>Compound 3>Compound *** work provides excellent models to understand the structureproperty relationship from the perspective of cocrystallization and Ti-O binding model and will further promote the application of TOCs as functional catalysts for organic transformation.

关键词： Titanium-oxo cluster Molecular model of anatase TiO_(2) High nuclearity π-conjugated chromophore Photocatalytic sulfoxidation

Tailoring microenvironment for efficient CO_(2)electroreduction through nanoconfinement strategy

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Nano Research 2024年第9期17卷 7880-7899页

作者： Lulu Chen Minhan Li Jia-Nan Zhang Key Laboratory of Advanced Energy Catalytic and Functional materials Preparation Country College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China

The electrocatalytic conversion of CO_(2)to produce fuels and chemicals holds great promise,not only to provide an alternative to fossil feedstocks,but also to use renewable electricity to convert and recycle the greenhouse gas CO_(2)to mitigate climate ***,the selectivity and reaction rates for the conversion of CO_(2)into desirable carbon-based products,especially multicarbon products with high added value,are still insufficient for commercial applications,which is attributed to insufficiently favourable microenvironmental conditions in the vicinity of the *** construction of catalysts/electrodes with confined structures can effectively improve the reaction microenvironment in the vicinity of the electrodes and thus effectively direct the reaction towards the desired *** this review,we firstly introduce the effects of the microenvironment at the electrode-electrolyte interface including local pH,local intermediate concentration,and local cation concentration on CO_(2)reduction reaction(CO_(2)RR)as well as the mechanism of action,and then shed light on the microenvironmental modulation within the confined space,and finally and most importantly,introduce the design strategy of CO_(2)RR catalyst/electrode based on the confinement effect.

关键词： CO_(2)reduction reaction microenvironment confinement effect catalyst design

Unique electromagnetic wave absorber for three-dimensional framework engineering with copious heterostructures

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Journal of materials Science & Technology 2024年第3期170卷 129-139页

作者： Liyuan Yu Qianqian Zhu Zhiqiang Guo Yuhang Cheng Zirui Jia Guanglei Wu Institute of materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China college of Chemistry and Chemical engineering Qingdao UniversityQingdao 266071China

In order to obtain high-performance electromagnetic wave absorbers,the adjustment of structure and components is *** on the above requirements,this system forms a three-dimensional frame structure consisting of MXene and transition metal oxides(TMOs)through efficient electrostatic *** three-dimensional network structure has rich heterojunction structures,which can cause a large amount of interface polarization and conduction losses in incident electromagnetic *** structures cause multiple reflections and scattering of electromagnetic waves,which is also an important reason for further increasing electromagnetic wave *** the doping ratio is 1:1,the system has the best impedance matching,the maximum effective absorption bandwidth(EAB max)can reach 5.12 GHz at 1.7 mm,and the minimum reflection loss(RL_(min))is-50.30 dB at 1.8 *** provides a reference for the subsequent formation of 2D-MXene materials into 3D materials.

关键词： MXene Three-dimensional frame Heterojunction structure Conduction loss Electromagnetic wave absorption

Self-assembly tungsten selenide hybrid ternary MOF derived magnetic alloys via multi-polarization to boost microwave absorption

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Nano Research 2024年第3期17卷 1625-1635页

作者： Tianbao Zhao Tingting Zheng Di Lan Yan Zhang Zhengshuo Sun Chao Wang Zirui Jia Guanglei Wu Institute of materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China School of materials Science and engineering Hubei University of Automotive TechnologyShiyan 442002China college of Chemistry and Chemical engineering Qingdao UniversityQingdao 266071China

Confronted with severe electromagnetic wave pollution,the development of high-performance electromagnetic wave shielding or absorbing materials is an effective way to deal with ***,double transition metal alloys and transition metal dichalcogenides have attracted extensive attention in electromagnetic wave absorption,but few reports have studied the effects of these two materials on electromagnetic wave absorption at the same *** this work,cobalt-based alloy with magnetic loss mechanism was selected for composition *** ternary metal-organic framework was prepared by the one-step method,and then CoCu/C was prepared by high temperature ***,in the hydrothermal process,ultra-thin tungsten selenide nanosheets were coated on the surface of magnetic component,and the final polyhedral WSe_(2)/CoCu/C composites with multiple heterogeneous interfaces were *** synergistic effect of dielectric and magnetic components optimizes impedance matching and allows more electromagnetic waves to enter the ***,through the conduction loss of high conductivity graphitized carbon,interfacial polarization,and dipole polarization of heterogeneous interfaces between the components,the magnetic loss provided by CoCu alloy can work together to maximize the attenuation ability of electromagnetic ***,the minimum reflection loss(RLmin)value of the composite reaches-53.43 dB when the matched thickness is 2.1 mm,while the maximum effective absorption bandwidth(EABmax)reaches 6.0 GHz at a thin thickness of 1.8 *** work provides some support and reference for the design of novel electromagnetic wave absorbing materials via the dielectric/magnetic loss synergistic mechanism.

关键词： metal-organic framework dielectric/magnetic loss transition metal dichalcogenide electromagnetic wave absorption

Surface reconstruction of heterostructures in alkaline medium towards enhanced electrocatalytic hydrogen evolution

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Rare Metals 2024年第6期43卷 2636-2647页

作者： Ming-Yang Yang Ji Yuan Xue-Lian Fu Jing-Jing Chen Jing Hu Zhou-Guang Lu Chen Liu Guangdong Research Center for Interfacial engineering of Functional materials Shenzhen Key Laboratory of Polymer Science and TechnologyShenzhen Key Laboratory of Energy Electrocatalytic MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Interfacial Science and engineering of materials Department of Materials Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China

Constructing heterostructures has proved to be a successful strategy to fabricate electrocatalysts with high efficiency for water ***,the structure evolution in alkaline hydrogen evolution reaction lacks investigation and the specific active center remains ***,we take the well-designed Ni_(3)S_(2)@VO_(2) heterostructures as a model to investigate the electrocatalytic activity and the surface reconstruction process of heterostructure catalysts in alkaline *** Ni_(3)S_(2)@VO_(2) heterostructures,with Ni_(3)S_(2) nanorods as the core and VO_(2) nanoflakes as the shell,coupled with the high conductive Ni_(3)S_(2),the hydrophilic VO_(2) and modulated electronic structures at the interfaces,exhibited prominent activity and superior stability at various current ***,the ex-situ characterizations confirmed that the surface reconstruction from Ni_(3)S_(2)@VO_(2) into Ni_(3)S_(2)@amorphous-Ni(OH)_(2) in alkaline media could optimize the water dissociation barrier and exposed large active area,thereby contributing to improved electrocatalytic *** study not only introduces novel high-performance electrocatalysts for hydrogen evolution reaction(HER),but also provides a new avenue for re-examining hetero-structural catalysts in alkaline solutions.

关键词： Heterostructures Ni_(3)S_(2)@VO_(2) Surface reconstruction Water dissociation Alkaline hydrogen evolution