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超高韧性磷酸镁水泥基复合材料压缩力学性能研究

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材料导报 2024年第17期38卷 13-24页

作者：冯虎闵智爽郭奥飞朱必洋陈兵黄昊郑州大学土木工程学院郑州450001 同济大学材料科学与工程学院上海201804 上海交通大学船舶海洋与建筑工程学院上海200240 中国水利水电科学研究院北京100038

磷酸镁水泥(Magnesium phosphate cement,MPC)是一种具有凝结时间短、早期强度高、粘结性能好等诸多优点的新型无机胶凝材料,但材料本身具有脆性性质,应变能力低。工程水泥基复合材料(Engineered cementitious composites,ECC)是通过在... 详细信息

磷酸镁水泥(Magnesium phosphate cement,MPC)是一种具有凝结时间短、早期强度高、粘结性能好等诸多优点的新型无机胶凝材料,但材料本身具有脆性性质,应变能力低。工程水泥基复合材料(Engineered cementitious composites,ECC)是通过在水泥基复合材料中添加高性能纤维制备而成。通过纤维增韧技术,可以制备出同时具备MPC和ECC优良特性的超高韧性磷酸镁水泥基复合材料(Ultra-high toughness magnesium phosphate cement-based composites,UHTMC)。本工作通过拉伸试验证实了UHTMC具有优异的拉伸力学性能、应变硬化和多缝开裂特征。通过试件的轴心抗压强度、极限压应变、受压弹性模量和泊松比分析了粉煤灰(Fly ash,FA)替代量(0%、15%、30%和45%)和养护龄期(14 d和28 d)对UHTMC压缩力学性能的影响规律。结果表明,UHTMC试件表现出良好的压缩韧性,随着粉煤灰替代量的增加和养护龄期的延长,试件的轴心抗压强度和受压弹性模量升高,但极限压应变降低,泊松比变化较小。通过对UHTMC的轴心受压应力-应变全曲线进行分析,提出和建立了轴心受压本构关系模型。最后,从微观层面上分析了粉煤灰替代量和养护龄期影响UHTMC宏观压缩力学性能的机理。

关键词：磷酸镁水泥粉煤灰超高韧性压缩性能本构关系

Optimizing the sulfur-resistance and activity of perovskite oxygen carrier for chemical looping dry reforming of methane

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Journal of Energy Chemistry 2024年第9期96卷 259-271页

作者： Yuelun Li Dong Tian Lei jiang Huicong Zuo LiNan Huang Mingyi chen Jianchun Zuo Hua Wang Kongzhai Li Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction Ministry of EducationKunming University of Science and TechnologyKunming 650093YunnanChina Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093YunnanChina

Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)***,we propose to modulate both the activity and resistance to sulfur poisoning by dual substitution of Mo and Ni ions with the Fe-sites of LaFeO_(3)*** is found that partial substitution of Ni for Fe substantially improves the activity of LaFeO_(3)perovskite,while Ni particles prefer to grow and react with H_(2)S during the long-term successive redox process,resulting in the deactivation of oxygen *** the presence of Mo in LaNi_(0.05)Fe_(0.95)O_(3−σ)perovskite,H_(2)S preferentially reacts with Mo to generate MoS_(2),and then the CO_(2)oxidation can regenerate Mo via removing *** addition,Mo can inhibit the accumulation and growth of Ni,which helps to improve the redox stability of oxygen *** LaNi_(0.05)Mo_(0.07)Fe_(0.88)O_(3−σ)oxygen carrier exhibits stable and excellent performance,with the CH_(4)conversion higher than 90%during the 50 redox cycles in the presence of 50 ppm H_(2)S at 800℃.This work highlights a synergistic effect in the perovskite oxides induced by dual substitution of different cations for the development of high-performance oxygen carriers with excellent sulfur tolerance.

关键词： Perovskite oxygen carriers Chemical looping reforming Sulfur-resistance Dual substitution Syngas

Cross-linked Electrospun Gel Polymer Electrolytes for Lithium-Ion Batteries

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Chinese Journal of Polymer Science 2024年第8期42卷 1021-1028页

作者： Xue Gong Qin Xiao Qing-Yin Li Wen-Cui Liang Feng chen Long-Yu Li Shi-Jie Ren College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

Lithium-ion batteries(LIBs)benefit from an effective electrolyte system design in both terms of their safety and energy storage ***,a series of precursor membranes with high porosity were produced using electrospinning technology by mixing PVDF and triblock copolymer(PS-PEO-PS),resulting in a porous structure with good interconnections,which facilitates the absorbency of a large amount of electrolyte and further increases the ionic conductivity of gel polymer electrolytes(GPEs).It has been demonstrated that post-cross-linking of the precursor membranes increa ses the rigidity of the nanofibers,which allows the polymer film to be dimensionally sta ble up to 260℃while maintaining superior electrochemical *** obtained cross-linked GPEs(CGPEs)showed high ionic conductivity up to 4.53×10^(-3)S·cm^(-1).With the CGPE-25,the assembled Li/LiFeP04 half cells exhibited good rate capability and maintained a capacity of 99.4%and a coulombic efficiency of99.3%at 0.1 *** results suggest that the combination of electrospinning technique and post-cross-linking is an effective method to construct polymer electrolytes with high thermal stability and steadily decent electrochemical performance,particularly useful for Lithium-ion battery applications that require high-temperature usage.

关键词： Electrospinning Cross-linked Gel polymer electrolytes Lithium-ion batteries

Highly efficient catalyst for 1,1,2-trichloroethane dehydrochlorination via BN_(3) frustrated Lewis acid-base pairs

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Nano Research 2024年第6期17卷 4773-4781页

作者： Yuxue Yue Fangmin Zuo Bolin Wang Xiaoling Xian Jun Tang Haifeng Zhang Zilong Zhang Qingping Ke Wei chen School of Chemical Engineering Northeast Electric Power UniversityJilin 132012China Industrial Catalysis Institute of Zhejiang University of Technology Hangzhou 310014China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China College of Chemistry and Chemical Engineering Anhui University of TechnologyMaanshan 243002China

In this study,a novel non-metallic carbon-based catalyst co-doped with boron and nitrogen(B,N)was successfully *** precisely controlling the carbonization temperature of a binary mixed ionic liquid,we selectively modified the doping site structure,ultimately constructing a B,N co-doped frustrated Lewis acid-base pair *** catalyst exhibited remarkable catalytic activity,selectivity,and stability in the dehydrochlorination reaction of 1,1,2-trichloroethane(TCE).Detailed characterization and theoretical calculations revealed that the primary active center of this catalyst was the BN_(3)*** to conventional graphitic N structures,the BN_(3)structure had a higher p-band center,ensuring superior adsorption and activation capabilities for TCE during the *** the BN_(3)site,three negatively charged nitrogen atoms acted as Lewis bases,while positively charged boron atoms acted as Lewis *** synergistic interaction facilitated the specific dissociation of chlorine and hydrogen atoms from TCE,significantly enhancing the 1,1-dichloroethene *** this research,we not only explored the active site structure and catalytic mechanism of B,N co-doped catalysts in depth but also provided an efficient,selective,and stable catalyst for the dehydrochlorination of TCE,contributing significantly to the development of non-metallic catalysts.

关键词： B N co-doped sites dehydrochlorination frustrated Lewis acid-base pairs catalytic mechanism

Nickel-iron in the second coordination shell boost single-atomicsite iridium catalysts for high-performance urea electrooxidation

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Nano Research 2024年第5期17卷 3919-3926页

作者： Xiaoyu chen Jiawei Wan Jing Chai Liang Zhang Fang Zhang Qinghua Zhang Lin Gu Lirong Zheng Ranbo Yu Department of Physical Chemistry School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory of Biochemical Engineering Key Laboratory of Biopharmaceutical Preparation and DeliveryChinese Academy of SciencesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Center for Combustion Energy School of Vehicle and MobilityState Key Laboratory of Intelligent Green Vehicle and MobilityTsinghua UniversityBeijing 100084China Analysis and Testing Center Beijing Institute of TechnologyBeijing 100081China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Single-atom catalysts(SACs)with high catalytic activity as well as great stability are demonstrating great promotion in electrocatalytic energy conversion,which is also a big challenge to ***,we proposed a facile synthetic strategy to construct nickel-iron bimetallic hydroxide nanoribbon stabilized single-atom iridium catalysts(Ir-NiFe-OH),where the nickel-iron hydroxide nanoribbon not only can serve as good electronic conductor,but also can well stabilize and fully expose single-atom *** as catalyst for urea oxidation reaction(UOR),it exhibited excellent UOR performance that it only needed a low operated potential of 1.38 V to achieve the current density of 100 mA·cm^(-2).In-situ Fourier transform infrared spectroscopy,X-ray absorption spectrum,and density functional theory calculations proved that Ir species are active centers and the existence of both Ni and Fe in the local structure of Ir atom can optimize the d-band center of Ir species,promoting the adsorption of intermediates and desorption of products for *** hydrogen evolution reaction(HER)/UOR electrocatalytic cell demanded voltages of 1.46 and 1.50 V to achieve 50 and 100 mA·cm^(-2),respectively,which demonstrated a higher activity and better stability than those of conventional *** work opens a new avenue to develop catalysts for UORs with boosted activity and stability.

关键词： single-atom iridium coordinate structure nanoribbon urea electrooxidation

Deactivation induced by metal sulfate over MnCeOx catalyst in NH_(3)-SCR reaction at low temperature

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Journal of Rare Earths 2024年第6期42卷 1056-1065,I0002页

作者： Qiao Xie Dongqi An Linsen Zhou Tingzhen Li Zhenghua Hu Menghan chen Menglan Ma Lei Zhang Jingfang Sun Lin Dong School of Environmental and Chemical Engineering Chongqing Three Gorges UniversityChongqing404000China Key Laboratory of Water Environment Evolution and Pollution Control in the Three Gorges Reservoir Chongqing Three Gorges UniversityChongqing.404000China Jiangsu Key Laboratory of Vehicle Emissions Control Center of Modern AnalysisSchool of EnvironmentNanjing UniversityNanjing210093China Institute of Materials China Academy of Engineering PhysicsMianyang621908China

Sulfate adsorption is one of the factors that cause the poisoning of catalyst in the low-temperature NH_(3) selective catalytic reduction reaction(NH_(3)-SCR).In this paper,by controlling the co-adsorption time of SO_(2) and O_(2) at 150℃,a range of sulfated MnCeOx catalysts with different contents of metal sulfate species were prepared to reveal the influence of metal sulfate species content on the catalytic performances and reaction mechanisms at low *** catalytic activity below 250℃rapidly decreases with increasing metal sulfate species *** results of characterizations shed light on the reduction of specific surface area,Mn^(4+)and Ce^(3+)content,and redox ability of MnCeOx owing to the formation of metal sulfate *** experiments reveal that metal sulfate species preferentially absorb on MnOx domains rather than on CeO_(2) domains,and the adsorbed metal sulfate species can suppress the Eley-Rideal and the Langmuir-Hinshelwood reaction mechanisms over the sulfated *** the above results are detrimental to the activity of sulfated MnCeOx in the low-temperature NH3-SCR reaction.

关键词： NH_(3)selective catalytic reduction MnCeOx catalyst Sulfation Low-temperature activity SO_(2)poisoning Rare earths

Synergetic pathways of water-energy-carbon in ecologically vulnerable regions aiming for carbon neutrality:a case study of Shaanxi,China

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Frontiers of Environmental Science & Engineering 2024年第9期18卷 1-15页

作者： Yingying Liu Hanbing Li Sha chen Lantian Zhang Sumei Li He Lv Ji Gao Shufen Cui Kejun Jiang Department of Environmental Science Key Laboratory of Beijing on Regional Air Pollution ControlBeijing University of TechnologyBeijing 100124China China Metallurgical Industry Planning and Research Institute Beijing 100711China Environmental Defense Fund Beijing 100007China Department of Financial Management Lishui UniversityLishui 323000China Energy Research Institute Beijing 100038China

Synergetic energy-water-carbon pathways are key issues to be tackled under carbon-neutral target and high-quality development worldwide,especially in ecologically vulnerable regions(EVRs).In this study,to explore the synergistic pathways in an EVR,a water-energy-carbon assessment(WECA)model was built,and the synergistic effects of water-energy-carbon were comprehensively and quantitatively analyzed under various scenarios of regional *** Province was chosen as the representative EVR,and Lower challenge(LEC)and Greater challenge(GER)scenarios of zerocarbon transition were set considering the technological maturity and regional energy *** results showed that there were limited effects under the zero-carbon transition of the entire region on reducing water withdrawals and improving the water *** the LEC scenario,the energy demand and CO2 emissions of Shaanxi in 2060 will decrease by 70.9%and 99.4%,respectively,whereas the water withdrawal and freshwater aquatic ecotoxicity potential(FAETP)will only decrease by 8.9%and 1.6%,*** could be attributed to the stronger demand for electricity in the energy demand sector caused by industrial transition *** GER scenario showed significant growth in water withdrawals(16.0%)and FAETP(36.0%)because of additional biomass *** promote the synergetic development of regional transition,EVRs should urgently promote zero-carbon technologies(especially solar and wind power technologies)between 2020 and 2060 and dry cooling technology for power generation before *** particular,a cautious attitude toward the biomass energy with carbon capture and storage technology in EVRs is strongly recommended.

关键词： Carbon neutrality Water withdrawals Water environment quality Ecologically vulnerable region Typical regional transition

A general and facile calcination method to synthesize single-site catalysts for highly efficient electrochemical CO_(2) reduction

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Nano Research 2024年第5期17卷 3895-3901页

作者： Rui Sui bingyan Wang Yongsheng Wang Jiajing Pei Wei Zhu Wenxing chen Chunhui Li Ailing Sun Zhongbin Zhuang Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084China College of Chemistry and Green Catalysis Center Zhengzhou UniversityZhengzhou 450001China State Key Lab of Organic-Inorganic Composites and Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

The electrochemical CO_(2) reduction reaction(CO_(2)RR)has received widespread attention as a promising method for producing sustainable chemicals and mitigating the global ***,we demonstrate a general and facile synthetic route for the metal-nitrogen-carbon(M-N-C)type catalyst by simply calcinating metal acetate and urea with commercial carbon black,which have potential application in CO_(2)*** synthesized Ni-NC-600 catalyst has the structure of single Ni atom coordinated with one N atom and three C atoms(Ni-N_(1)C_(3)),which is suggested by X-ray absorption *** Ni-NC-600 catalyst exhibits high CO_(2)RR catalytic performance and a high CO Faraday efficiency above 98%in a wide potential range from-0.7 to-1.3 V(*** hydrogen electrode(RHE)),superior to most of the reported Ni-N-C *** work has developed a facile strategy to synthesize high performance CO_(2)RR catalyst.

关键词： nickel single atom catalyst CO_(2)reduction reaction CO production electrocatalyst

Chiral phonon activated spin Seebeck effect in chiral materials

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 149-155页

作者： Xiao Li Jinxin Zhong Jinluo cheng Hao chen Huiqian Wang Jun Liu Dali Sun Lifa Zhang Jun Zhou Phonon Engineering Research Center of Jiangsu Province Center for Quantum Transport and Thermal Energy ScienceSchool of Physics and TechnologyNanjing Normal UniversityNanjing 210023China Center for Phononics and Thermal Energy Science China-EU Joint Lab for NanophononicsSchool of Physics Science and EngineeringTongji UniversityShanghai 200092China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of ScienceChangchun 130033China Department of Mechanical and Aerospace Engineering North Carolina State UniversityRaleigh NC 27606USA Department of Physics North Carolina State UniversityRaleigh NC 27695USA Organic and Carbon Electronics Laboratories(ORaCEL) North Carolina State UniversityRaleigh NC 27606USA

Efficient generation of spin polarization is very important for spintronics and quantum computation. In chiral materials without magnetic order nor spin-orbit coupling, we find a new spin selectivity effect—chiral phonon activated spin Seebeck(CPASS)effect. Starting with the nonequilibrium distribution of chiral phonons under a temperature gradient, the CPASS coefficients are computed based on the Boltzmann transport theory. With both the phonon-drag and band transport contributions, the spin accumulations generated by the CPASS effect exhibit quadratic dependence on the temperature gradient. The strength of the CPASS effect and the relative magnitude of both contributions are tunable by the chemical potential modulation. The CPASS effect, which gives a promising explanation on the traditional chiral-induced spin selectivity effect, provides opportunities for the exploration of advanced spintronic devices based on chiral materials even in the absence of any magnetic order and spin-orbit coupling.

关键词： spin Seebeck effect chiral phonon phonon-drag contribution efficient spin generation