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Journal of Magnesium and Alloys 2024年第2期12卷 815-824页

作者： Tangpeng Ma Jin Wang Kaiming Cheng Chengwei Zhan Jixue Zhou Jingyu Qin Guochen Zhao Xinfang Zhang Shandong Provincial Key laboratory of High Strength Lightweight Metallic materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Sciences)Jinan 250014China Key laboratory for Liquid-Solid Structural Evolution and Processing of materials Ministry of EducationShandong UniversityJinan 250061China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

In an effort to clarify the formation mechanism of LPSO structure in Mg-Y-Zn alloy,the chemical environment and structural ordering in liquid Mg-rich Mg-Y-Zn system are investigated with the aid of ab-initio molecular dynamics *** liquid Mg-rich Mg-Y alloys,the strong Mg-Y interaction is determined,which promotes the formation of fivefold symmetric local *** Mg-Zn alloys,the weak Mg-Zn interaction results in the fivefold symmetry weakening in the liquid *** to the coexistence of Y and Zn,the strong attractive interaction is introduced in liquid Mg-Y-Zn ternary alloy,and contributes to the clustering of Mg,Y,Zn launched from *** is more,the distribution of local structures becomes closer to that in pure Mg compared with that in binary Mg-Y and Mg-Zn *** results should relate to the origins of the Y/Zn segregation zone and close-packed stacking mode in LPSO structure,which provides a new insight into the formation mechanism of LPSO structure at atomic level.

关键词： Mg-Y-Zn Chemical environment Structural ordering ab-initio molecular dynamics

Construction of core@double-shell structured energetic composites with simultaneously enhanced thermal stability and safety performance

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Defence Technology（防务技术） 2024年第4期34卷 134-142页

作者： Peng Wang Wen Qian Ruolei Zhong Fangfang He Xin Li Jie Chen Li Meng Yinshuang Sun Guansong He Institute of Chemical materials China Academy of Engineering PhysicsMianyang 621900China State Key laboratory of environment-friendly Energy materials School of Materials and ChemistrySouthwest University of Science and TechnologyMianyang 621010China

The poor thermal stability and high sensitivity severely hinder the practical application of hexanitrohexaazaisowurtzitane(CL-20).Herein,a kind of novel core@double-shell CL-20 based energetic composites were fabricated to address the above *** coordination complexes which consist of natural polyphenol tannic acid(TA) and Fe~Ⅲ were chosen to construct the inner shell,while the graphene sheets were used to build the outer *** resulting CL-20/TA-Fe~Ⅲ/graphene composites exhibited simultaneously improved thermal stability and safety performance with only 1 wt% double-shell content,which should be ascribed to the intense physical encapsulation effect from inner shell combined with the desensitization effect of carbon nano-materials from outer *** phase transition(ε to γ) temperature increased from 173.70 ℃ of pure CL-20 to 191.87℃ of CL-20/TA-Fe~Ⅲ/graphene ***,the characteristic drop height(H_(50)) dramatically increased from 14.7 cm of pure CL-20 to112.8 cm of CL-20/TA-Fe~Ⅲ/graphene composites,indicating much superior safety performance after the construction of the double-shell *** general,this work has provided an effective and versatile strategy to conquer the thermal stability and safety issues of CL-20 and contributes to the future application of high energy density energetic materials.

关键词： CL-20 Double-shell structure Thermal stability Safety performance Tannic acid Graphene sheets

The risk factors and threshold level of subchronic inhalation exposure of reclaimed water

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Journal of environmental Sciences 2024年第3期137卷 639-650页

作者： Jiayang Kong Yun Lu Yunru Ren Menghao Chen Gang Liu Liangliang Shi State Key Joint laboratory of environment Simulation and Pollution Control State Environment Protection Key Laboratory of Microorganism Application and Risk ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China

Inhalation of reclaimed water is known to cause lung infammation,and free endotoxins have been shown to be a major risk factor for acute *** exposure has also been shown to induce infammatory responses with visible tissue ***,subchronic risk factors have yet to be identified,and a threshold for the protection of occupational populations during urban reuse is *** this study,potential risk factors in reclaimed water were examined by subchronic exposure with fractionated reclaimed water,and the health risk threshold was tested with a series of diluted reclaimed ***,following a 12-week exposure,macromolecules and microorganisms were found to be two major risk factors in reclaimed water that could cause pulmonary infammation,including increased proportion of polymorphonuclear leukocytes in bronchoalveolar fuid,formation of inducible bronchus-associated lymphoid tissue,and elevation of Immunoglobulin A ***,infammation persisted after a 4-week recovery *** calculated threshold of reclaimed water exposure for mice was 31.8 Endotoxin Unit(EU)/(kg·day)under when exposed to 50%additional relative humidity from reclaimed water at 25℃ for 2 hr/***,the subchronic threshold estimate for humans under the same exposure conditions was found to be 12.2 EU/(kg·day),corresponding to endotoxin levels of 61.7 EU/mL in reclaimed *** threshold level of endotoxin was lower than that in most non-potable reclaimed *** findings of this study suggest that occupational exposure of reclaimed water can serve as a potential risk to workers.

关键词： Reclaimed water Inhalation exposure Risk factor Threshold Infammation Endotoxin

Construction of a Cu@hollow TS-1 nanoreactor based on a hierarchical full-spectrum solar light utilization strategy for photothermal synergistic artificial photosynthesis

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Carbon Energy 2024年第2期6卷 25-36页

作者： Sixian Zhu Qiao Zhao Hongxia Guo Li Liu Xiao Wang Xiwei Qi Xianguang Meng Wenquan Cui Hebei Key laboratory for environment Photocatalytic and Electrocatalytic materials College of Chemical EngineeringNorth China University of Science and TechnologyTangshanChina School of materials Science and Engineering National Institute for Advanced MaterialsTKL of Metal and Molecule-Based Material ChemistryNankai UniversityTianjinChina Hebei Iron and Steel laboratory TangshanChina

The artificial photosynthesis technology has been recognized as a promising solution for CO_(2) *** catalysis has been proposed as a novel strategy to promote the efficiency of artificial photosynthesis by coupling both photochemistry and ***,strategies for maximizing the use of solar spectra with different frequencies in photothermal catalysis are urgently ***,a hierarchical full-spectrum solar light utilization strategy is *** on this strategy,a Cu@hollow titanium silicalite-1 zeolite(TS-1)nanoreactor with spatially separated photo/thermal catalytic sites is designed to realize high-efficiency photothermal catalytic artificial *** space-time yield of alcohol products over the optimal catalyst reached 64.4μmol g−1 h−1,with the selectivity of CH3CH2OH of 69.5%.This rationally designed hierarchical utilization strategy for solar light can be summarized as follows:(1)high-energy ultraviolet light is utilized to drive the initial and difficult CO_(2) activation step on the TS-1 shell;(2)visible light can induce the localized surface plasmon resonance effect on plasmonic Cu to generate hot electrons for H2O dissociation and subsequent reaction steps;and(3)low-energy near-infrared light is converted into heat by the simulated greenhouse effect by cavities to accelerate the carrier *** work provides some scientific and experimental bases for research on novel,highly efficient photothermal catalysts for artificial photosynthesis.

关键词： artificial photosynthesis full spectrum nanoreactors photothermal catalysis

Integrated multi-scale approach combining global homogenization and local refinement for multi-field analysis of high-temperature superconducting composite magnets

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 747-762页

作者： Hanxiao GUO Peifeng GAO Xingzhe WANG Key laboratory of Mechanics on Western Disaster and environment of Ministry of Education Key Laboratory of Special Function Materials and Structure Design of Ministry of EducationCollege of Civil Engineering and MechanicsLanzhou UniversityLanzhou 730000China

Second-generation high-temperature superconducting(HTS)conductors,specifically rare earth-barium-copper-oxide(REBCO)coated conductor(CC)tapes,are promising candidates for high-energy and high-field superconducting *** respect to epoxy-impregnated REBCO composite magnets that comprise multilayer components,the thermomechanical characteristics of each component differ considerably under extremely low temperatures and strong electromagnetic *** numerical models include homogenized orthotropic models,which simplify overall field calculation but miss detailed multi-physics aspects,and full refinement(FR)ones that are thorough but computationally ***,we propose an extended multi-scale approach for analyzing the multi-field characteristics of an epoxy-impregnated composite magnet assembled by HTS pancake *** approach combines a global homogenization(GH)scheme based on the homogenized electromagnetic T-A model,a method for solving Maxwell's equations for superconducting materials based on the current vector potential T and the magnetic field vector potential A,and a homogenized orthotropic thermoelastic model to assess the electromagnetic and thermoelastic properties at the macroscopic *** then identify“dangerous regions”at the macroscopic scale and obtain finer details using a local refinement(LR)scheme to capture the responses of each component material in the HTS composite tapes at the mesoscopic *** results of the present GH-LR multi-scale approach agree well with those of the FR scheme and the experimental data in the literature,indicating that the present approach is accurate and *** proposed GH-LR multi-scale approach can serve as a valuable tool for evaluating the risk of failure in large-scale HTS composite magnets.

关键词： epoxy-impregnated high-temperature superconducting(HTS)magnet multi-scale method global homogenization(GH) local refinement(LR) multi-field analysis

Effect of V on high-temperature mechanical properties of Al-5Cu-1.5Ni alloy

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Journal of Iron and Steel Research International 2024年第7期31卷 1792-1810页

作者： Jun-ge Cui Yong-bin Chen Xiang-zhou Fu Hai-long Yang Han-zhang Wang An-min Li Li-wen Pan School of Resources Environment and MaterialsGuangxi UniversityNanning 530004GuangxiChina State Key laboratory of Featured Metal materials and Life-Cycle Safety for Composite Structures Nanning 530004GuangxiChina Guangxi Higher Education Key laboratory of Advanced materials Nanning 530004GuangxiChina

The effects of V on microstructure,room temperature,and high-temperature(350℃)mechanical properties of Al-5Cu-1.5Ni alloy were *** results show that Al-5Cu-1.5Ni-xV alloys mainly compriseα-Al,Al_(2)Cu,Al_(3)(Ni,Cu)_(2),Al_(3)Ni,Al7Cu4Ni,and Al_(10)V *** addition of V can signally refineα-Al dendritic structure,which improves the mechanical properties of the as-cast alloys at room and high *** T6 heat treatment(540℃/12 h/WC+170℃/8 h/AC),α-Al,network skeleton structure Al_(3)(Ni,Cu)_(2),and Al_(10)V phases all show coarsening,while the fine nano-θ'-Al_(2)Cu precipitated from the matrix and dispersed *** introduction of V promotes the quantity of precipitatedθ'-Al_(2)Cu *** ultimate tensile strength of the heat-treated alloys at room and high temperatures is greatly improved compared to that of the as-cast *** highest high-temperature ultimate tensile strength of the alloys with V is 111.8 MPa,21.5%higher than that of the base *** analysis shows that the improvement of high-temperature mechanical properties after heat treatment is mainly due to the introduction of V,increasing the precipitated quantity of nano-θ'-Al_(2)Cu particles and improving its thermal *** dispersion strengthening effect ofθ'-Al_(2)Cu particles exceeds the weakening effect of other adverse microstructures on the mechanical properties.

关键词： Al-Cu-Ni-V alloy θ'-Al_(2)Cu phase Heat treatment Microstructure Mechanical property

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

Dielectric nanocomposites with superb high-temperature capacitive performance based on high intrinsic dielectric constant polymer

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Nano Research 2024年第9期17卷 8504-8512页

作者： Ding Ai Yuan Chang Haoliang Liu Chenglong Wu Yao Zhou Yuting Han Hao Yu Bing Xiao Yonghong Cheng Guanglei Wu Zirui Jia State Key laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi’an Jiaotong UniversityXi’an 710049China Institute of materials for Energy and environment State Key Laboratory of Bio-Fibers and Eco-TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China

Advancements in power electronics necessitate dielectric polymer films capable of operating at high temperatures and possessing high energy *** significant strides have been achieved by integrating inorganic fillers into high-temperature polymer matrices,the inherently low dielectric constants of these matrices have tempered the magnitude of *** this work,we report an innovative nanocomposite based on sulfonylated polyimide(SPI),distinguished by the incorporation of sulfonyl groups within the SPI backbone and the inclusion of wide bandgap hafnium dioxide(HfO_(2))*** nanocomposite has demonstrated notable enhancements in thermal stability,dielectric properties,and capacitive performance at elevated *** simulations at both molecular and mesoscopic levels have elucidated the mechanisms behind these improvements,which could be attributed to confined segmental motion,an optimized electronic band structure,and a diminished incidence of dielectric breakdown ascribed to the presence of sulfonyl ***,the SPI-HfO_(2)nanocomposite demonstrates a high charge-discharge efficiency of 95.7%at an elevated temperature of 150℃and an applied electric field of 200 MV/***,it achieves a maximum discharged energy density of 2.71 J/cm^(3),signalling its substantial potential for energy storage applications under extreme conditions.

关键词： dielectric polymer nanocomposites high-temperature high dielectric constant sulfonyl groups energy storage performance

Polarization engineering in porous organic polymers for charge separation efficiency and its applications in photocatalytic aerobic oxidations

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Science China Chemistry 2024年第3期67卷 1000-1007页

作者： Kun Wu Pei-Wen Cheng Xin-Yi Liu Ji Zheng Xiao-Wei Zhu Mo Xie Puxin Weng Weigang Lu Dan Li College of Chemistry and materials Science Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsJinan UniversityGuangzhou 510632China Guangdong Rare Earth Photofunctional materials Engineering Technology Research Center School of Chemistry and EnvironmentJiaying UniversityMeizhou 514015China

Photocatalytic aerobic oxidation reactions are largely governed by the efficiency of charge separation and subsequent reactive oxygen species(ROS) generation. Herein, we report a polarization engineering strategy to promote the charge separation and ROS generation efficiency by substituting the benzene unit with furan/thiophene in porous organic polymers(POPs). Benefiting from the extent of local polarization, the thiophene-containing POP(JNU-218) exhibits the best photocatalytic performance in aerobic oxidation reactions, with a yield much higher than those for the furan-containing POP(JNU-217) and the benzenecontaining POP(JNU-216). Experimental studies and theoretical calculations reveal that the increase of local polarization can indeed reduce the exciton binding energy, and therefore facilitate the separation of electron-hole pairs. This work demonstrates a viable strategy to tune charge separation and ROS generation efficiency by modulating the dipole moments of the building blocks in porous polymeric organic semiconductors.

关键词： porous organic polymer local polarization photocatalytic aerobic oxidation charge separation reactive oxygen species exciton binding energy

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Identification of the optimal doping position of hetero-atoms in chalcogen-doped Fe-N-C catalysts for oxygen reduction reaction

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Particuology 2024年第6期89卷 99-108页

作者： Weihao Liu Huanhuan He Qingtao Liu Xin Wan Jianglan Shui School of materials Science and Engineering Beihang UniversityBeijing100191China School of Space and environment Beihang UniversityBeijing102206China Tianmushan laboratory Hangzhou310023China

The excellent oxygen reduction reaction(ORR)activity of Fe–N–C catalysts in acidic media makes them potential for low-cost proton exchange membrane fuel *** recent years,it has been shown that heteroatoms(B,O,S,P,Cl,F,etc.)can be used as electron-withdrawing groups to modulate the planar structure and electron distribution of the Fe–Nx active sites to achieve simultaneous improvement of catalytic activity and ***,the optimal location of the heteroatoms remains ***,taking chalcogen heteroatoms(S and Se)as an example,we control the doping positions and investigate their effect on the ORR performance of the Fe–N–C *** first coordination shell of the iron single atom is identified as the optimal doping *** optimized catalysts Fe–N_(3)Se_(1)/NC and Fe–N_(3)Se_(1)/NC demonstrate improved activity and stability in both half cells and fuel *** work provides insights into the enhancement mechanism of heteroatom doping in single-atom catalysts.

关键词： Oxygen reduction reaction Fe-N-C catalysts Hetero-atom doping Doping position Enhancement mechanism