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Influence of MB-value of Manufactured Sand on the Shrinkage and Cracking of High Strength Concrete

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Journal of Wuhan University of Technology(materials Science) 2009年第2期24卷 321-325页

作者：王稷良 key laboratory of road structure and material ministry of communications (Beijing) Research Institute of Highway Ministry of Communication

The relation between methylene blue （MB） value of MS and its limestone dust content and clay content was investigated. The effects of MB value ranging from 0.35 to 2.5 on the workability of fresh concrete and crack propagation characteristics at the age of 24 hours, and effects on the mechanical properties, dry shrinkage of the harden concrete were tested. The experimental results show that the MB value is not related with the limestone dust content of MS, but in direct proportion to clay content. With the increase of MB value, the concrete workability decreases, and the flexural strength and 7 d compressive strength reduce markedly, whearas the 28 d compressive strength is not affected. When the MB-value is less than or equal to 1.35, the change of the MB-value has a little influence on early plastic cracking and dry shrinkage property of concrete, but when the MB-value is more than 1.35, the tendency of plastic cracking and dry shrinkage is remarkable.

关键词： manufactured sand methylene blue value high strength concrete anti-cracking shrinkage

Evaluation on High-temperature Adhesion Performance of Hot-applied Sealant for Asphalt Pavement

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Journal of Wuhan University of Technology(materials Science) 2014年第6期29卷 1237-1241页

作者：李峰 LI Tinggang SHI Xiaopei key laboratory of road structure & material Research Institute of Highway Ministry of Transport

In order to investigate the high-temperature performances of the asphalt pavement hot-applied sealant, as well as to reduce failures of the sealant pullout, the softening point test and the flow test（two existing methods for evaluating high-temperature performances） were conducted. It was found that both tests could not accurately reflect the adhesion performances of the sealant at high temperatures. For this purpose, the adhesion test for PSAT（pressure sensitive adhesive tape） has been taken as a reference to develop a device that is suitable for evaluating the adhesion performances, by modifying relevant test parameters according to the road conditions at high temperatures. Thirteen common sealants were tested in the modified adhesion test, softening point test and f low test. The experimental results show that no significant correlation（p〉0.05） exists between the adhesion value, softening point, adhesion value and flow value; while a significant correlation（p〈0.05） exists between the softening point and flow value. The modified adhesion test is efficient in distinguishing the hightemperature adhesion performances of different sealants, and can be used as a standard method for evaluating such performances.

关键词： hot-applied sealant pullout high-temperature performance adhesion performance modified adhesion test

Preparation and mechanical properties of Fe_3Al/Al_2O_3 nano-/micro-composite

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中国有色金属学会会刊：英文版 2003年第6期13卷 1376-1380页

作者：尹衍升龚红宇范润华王昕谭训彦 key laboratory for material Liquid structure and Heredity of Education ministry

Al2O3 matrix composites reinforced with Fe3Al nano-particles were fabricated by hot processing at 1 4501 600 ℃. The effect of Fe3Al content on the densification, mechanical properties and microstructure of the composites was investigated. The results show that some elongated Al2O3 grains are observed. Fe3Al particles are mainly situated at grain boundaries of the matrix while smaller particles are trapped within the alumina grains. The addition of Fe3Al nanoparticles improves the mechanical properties of alumina. The maximum strength and toughness of the Fe3Al/Al2O3 nanocomposites are 832 MPa and 7.96 MPa·m1/2, respectively.

关键词： Fe3Al/Al2O3 纳米复合材料铝合金制备机械性能

Low-temperature chlorination roasting technology for the simultaneous recovery of valuable metals from spent LiCoO_(2)cathode material

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International Journal of Minerals,Metallurgy and materials 2025年第1期32卷 80-91页

作者： Junjie Shi Changle Hou Jingjing Dong Dong Chen Jianzhong Li key laboratory for Ecological Metallurgy of Multimetallic Mineral(ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

With the continuous increase in the disposal volume of spent lithium-ion batteries(LIBs),properly recycling spent LIBs has become essential for the advancement of the circular *** study presents a systematic analysis of the chlorination roasting kinetics and proposes a new two-step chlorination roasting process that integrates thermodynamics for the recycling of LIB cathode *** activation energy for the chloride reaction was 88.41 kJ/mol according to thermogravimetric analysis–derivative thermogravimetry data obtained by using model-free,model-fitting,and Z(α)function(αis conversion rate).Results indicated that the reaction was dominated by the first-order(F1)model when the conversion rate was less than or equal to 0.5 and shifted to the second-order(F2)model when the conversion rate exceeded *** conditions were determined by thoroughly investigating the effects of roasting temperature,roasting time,and the mass ratio of NH_(4)Cl to LiCoO_(2).Under the optimal conditions,namely 400℃,20 min,and NH_(4)Cl/LiCoO_(2)mass ratio of 3:1,the leaching efficiency of Li and Co reached 99.43% and 99.05%,*** of the roasted products revealed that valuable metals in LiCoO_(2)transformed into CoCl_(2) and ***,the reaction mechanism was elucidated,providing insights for the establishment of a novel low-temperature chlorination roasting technology based on a crystal structure *** technology can guide the development of LIB recycling processes with low energy consumption,low secondary pollution,high recovery efficiency,and high added value.

关键词： spent lithium-ion battery thermodynamics chlorination roasting kinetics circular economy

Current situations,advantages/disadvantages and future developments of resilient deformation characterizations of unbound granular material:A state-of-the-art review

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第6期10卷 964-1000页

作者： Shaohui Li Peiwen Hao key laboratory of road structure and material School of HighwayChang'an UniversityXi'an 710064China key laboratory of road and Traffic Engineering of ministry of Education Tongji UniversityShanghai 201804China

A state-of-the-art review was delivered in the manuscript to analyze the current situations and the advantages/disadvantages of resilient deformation related issues to the unbound granular material(UGM),including testing methods,influencing factors and constitutive models,through which the bottlenecks in UGM resilient deformation characterizations were located and new theories and future research recommendations were *** with other testing methods,the hollow cylinder test and true triaxial test are the only two to determine the anisotropic moduli of the *** significant advantages are observed in more advanced test apparatus such as true triaxial test,further improvements should be made,such as more advanced process identification control algorithm,to more conveniently control the nine independent hydraulic system and accurately measure UGM anisotropic *** and conflicts in understanding the influencing factors to UGM resilient modulus were located,such as the stress history,the residual stress,the dry density,the gradation/fine content and the freeze-thaw cycle,based on which future research could be *** reviewing evolutions of the UGM constitutive models and comparing their representativeness and complexity comprehensively,major drawbacks were discovered and a new theory was proposed afterward to modify the UGM constitutive model,although further validations are still needed.

关键词： Unbound granular material Resilient characterization Testing method Influencing factor Constitutive model

Effect of Methylene Blue (MB)-value of Manufactured Sand on the Durability of Concretes

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Journal of Wuhan University of Technology(materials Science) 2012年第6期27卷 1160-1164页

作者：王稷良 NIU Kaimin TIAN Bo SUN liqun key laboratory of road structure and material ministry of communications(Beijing) Research Institute of Highway Ministry of CommunicationBeijing 100088China Guizhou Province Building materials Product Quality Supervision and Inspection Center Guiyang 550002China

The relation between the methylene blue （MB） value of MS and its limestone powder content and clay content was investigated. The effects of MB values ranging from 0.35 to 2.5 on the workability of fresh concrete, the mechanical properties, the resistance to freezing as well as the resistance to chlorine ion permeation of the hardened concrete were all investigated. The experimental results showed that the MB value had no correlation with the limestone powder content of MS, while it was directly related to the clay content. With an increase of MB value, concrete workability decreased, as did the flexural and 7-day compressive strengths, however, the 28-day compressive strength was not affected. Furthermore, influence of MB value on concretes of different strength levels was different. For low-strength concretes, an increase of MB value could improve its impermeability, but this was not the case for high-strength concretes. Instead, their resistance to chloride ion permeability decreased slightly. However, even a slight increase in MB value remarkably accelerated freeze-thaw damage of MS concrete. It was thus concluded that the critical MB value of 1.4 would not cause significant deterioration in the performance of MS concretes.

关键词： manufactured sand methylene blue value clay content resistance to freezing chlorine ionpermeability coefficient

Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 528-547页

作者： Jiaolong Liu Siyu Zhang Dan Qu Xuejiao Zhou Moxuan Yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi Zhou Kai Tao Mengyang Li Bing Wei Hongjing Wu Mengyang Li Bing Wei Hongjing Wu School of Physics Xidian UniversityXi’an 710071People’s Republic of China School of Advanced materials and Nanotechnology State Key Discipline Laboratory of Wide Band Gap Semiconductor TechnologyXidian UniversityXi’an 710071People’s Republic of China School of Microelectronics Xidian UniversityXi’an 710071People’s Republic of China School of Telecommunication Engineering Xidian UniversityXi’an 710071People’s Republic of China MOE key laboratory of material Physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China The ministry of Education key laboratory of Micro and Nano Systems forAerospace School of Mechanical EngineeringNorthwestern PolytechnicalUniversityXi’an 710072People’s Republic of China

Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic *** methods,however,constrain their delicate ***,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon *** unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial ***“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first ***,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric *** defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response.

关键词： Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption

Anti-rutting performance evaluation of modified asphalt binders: A review

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第3期8卷 339-355页

作者： Yan Li Peiwen Hao Chaozhi Zhao Jwnqiang Ling Tao Wu Dewen Li Jingwen Liu Bowei Sun key laboratory for road structure&material of ministry of Transport Chang'an UniversityXi'an 710064China Shaanxi Prouindal Commimication Constriiction Group Xi'an 710075China

Asphalt pavement inevitably suffers rutting distress induced by repeated loads under high temperatures, which can be effectively alleviated by the modification of asphalt *** paper summarized the asphalt modifiers for enhancing the performance of asphalt pavement at high temperatures in terms of the modifier type, additive amount and improving effect. Then, the anti-rutting performance evaluation methods of asphalt binder were introduced with details, including the ring and ball(R&B) test, the dynamic viscosity test, the zero/low shear viscosity(ZSV/LSV) test, the dynamic shear rheometer(DSR) test,the repeated creep and recovery(RCR) test, and the multiple stress creep and recovery(MSCR) test. Furthermore, the sensitivity of the evaluation method to asphalt modifier was analyzed using the normalization method. It was found that the indicators from the MSCR test could clearly reveal the influence of asphalt modifiers on high temperature performance of asphalt binder. But it still had some limitations affecting the accuracy of evaluation results, such as the number of creep-recovery cycles, the stress level and the recovery time. In addition, according to the rutting resistance improvement ratio(RRIR),the styrene-butadiene-styrene(SBS) modifier performed better in improving the rutting resistance of asphalt binder, compared with other modifiers when added within the usual dosage range.

关键词： road engineering Asphalt modifier Rutting resistance Performance evaluation Normalization method Sensitivity analysis

The effect of welding heat input on the weldpool behavior in MIG welding

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Science China(Technological Sciences) 2002年第3期45卷 291-299页

作者：孙俊生武传松 1. key laboratory of Liquid structure and Heredity of material of ministry of Education Shandong University 250061 Jinan China

For metal-inert gas welding (MIG), the welding heat input includes the arc heat flux on the surface of workpiece and the volumetric distribution of droplets’ heat content within the weldpool. Based on the general principle of arc physics and the physical nature of the action of droplets and weldpool, a distribution mode of current density on the deformed weldpool surface and the heat content of filler metal droplets inside the weldpool is established in this paper. Numerical analysis is used to study the distribution of current density in MIG welding, the distribution mode of the heat content of filler metal droplets, weldpool geometry, the fluid flow and temperature profiles. Experiments are performed to prove the reliability of the calculated mode.

关键词： arc heat flux, droplets' heat content, distribution mode, weldpool behavior