检索结果-内蒙古大学图书馆

Fabrication and characterization of mullite fiber-based porous ceramics with mixed fiber lengths for high-temperature gas filtration

引用

Ceramics International 2025年第17期51卷 23214-23223页

作者： Zheng, Dazhi Zhu, Ruijian Hu, Yuwen Liang, Shiou Sun, Huiying Wang, Zengmei State Key Laboratory of Engineering Materials for Major Infrastructure Jiangsu Key Lab. of Construction Materials School of Materials Science and Engineering Southeast University Nanjing211189 China School of Materials Science and Engineering Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing Institute of Technology Nanjing211167 China

The emissions and particulate pollutants (PM) from industrialization and other human activities have become a significant threat to human health. Researchers have experimented with various fiber-bonded filters, but there are still relatively few products with good high-temperature resistance. In this paper, a fiber-bonded porous ceramic with high porosity was prepared by vacuum filtration combined with freeze-drying using two homemade mullite fibers with different length-to-diameter ratios as raw materials and mullite sol as binder. When the content of fine fibers is 40 %, the product has a better overall performance, its density is 0.63g/cm3, porosity is 74 %, strength is 0.77 MPa, thermal conductivity is 0.153 W m−1 K−1. When the airflow rate of 2 L/min, the pressure drop is 80 Pa, the filtration efficiency of about 99 %, the QF is 0.08 pa−1, The mullite fiber-bonded porous ceramics prepared through a simple process exhibit excellent filtration performance, offering a wide range of potential applications. © 2025

关键词： Thermal conductivity of gases

来源：评论

学校读者我要写书评

暂无评论

Dielectric–magnetic manipulation of reduced graphene oxide permittivity for enhanced electromagnetic wave absorption

引用

Journal of advanced Ceramics 2024年第12期13卷 1974-1984页

作者： Kaili Zhang Zhen Wang Yuefeng Yan Guansheng Ma Renchao Che Dechang Jia Xiaoxiao Huang Yu Zhou State Key Laboratory of Precision Welding&Joining of Materials and Structures Harbin Institute of TechnologyHarbin 150001China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China MIIT Key Laboratory of Advanced Structural-Functional Integration Materials&Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438China

Graphene is a promising electromagnetic wave absorption(EMWA)material because of its structural designability,controllab.e electromagnetic properties,and excellent ***,the impedance mismatch caused by high conductivity and dielectric properties has seriously hindered the application of graphene in the EMWA *** this work,based on the dielectric dispersion behavior of ideal broadband absorption as a guide,a Fe microsheet/reduced graphene oxide(Fe/RGO)composite was prepared by simple hydrothermal and thermal reduction *** permittivity of RGO is optimized by adjusting the content of anisotropic Fe microsheets,and a balance between attenuation ability and impedance matching is *** calculations and off-axis electron holography results reveal that the abundant polar sites and heterogeneous interfaces of Fe and RGO enhance the dipole and interface *** threedimensional(3D)conductive network structure contributes to multiple reflections of incident electromagnetic waves and conduction *** natural and exchange resonances and eddy current loss caused by anisotropic Fe microsheets further increase magnetic *** on the dielectric-magnetic loss mechanism and good impedance matching,Fe/RGO achieves a minimum reflection loss(RL_(min))of−67.95 dB at 8.48 GHz and a maximum effective absorption bandwidth(EAB_(max))of 6.91 GHz(11.09–18 GHz)with a low filling content of 10 wt%.In addition,Fe/RGO has excellent radar stealth performance,with a radar cross section(RCS)of−31.21 dBm^(2) at 0°.Therefore,the proposed strategy and theoretical analysis provide a reference for the microstructure design,composition,and mechanism analysis of EMWA materials.

关键词： electromagnetic wave absorption(EMWA) Fe microsheets reduced graphene oxide(RGO) dielectric-magnetic loss impedance matching

来源：评论

学校读者我要写书评

暂无评论

Insights into the dual effects of Ti on the grain refinement and mechanical properties of hypoeutectic Al-Si alloys

引用

Journal of materials Science & Technology 2024年第22期189卷 44-59页

作者： Ziyuan Zhao Daoxiu Li Xirui Yan Yan Chen Zhe Jia Dongqing Zhang Mengxia Han Xu Wang Guiliang Liu Xiangfa Liu Sida Liu Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China Laboratory for Multiscale Mechanics and Medical Science SV LABSchool of AerospaceXi’an Jiaotong UniversityXi’an 710049China School of Materials Science and Engineering Jiangsu Key Laboratory for Advanced Metallic MaterialsSoutheast UniversityNanjing 211189China

Hypoeutectic Al-Si alloys are becoming increasingly popular in automotive and aerospace engineering fields due to their excellent overall performance,and grain refinement is regarded as an important way to improve casting and mechanical ***(Ti)is a basic element for grain refinement;thus,a certain amount of Ti is often included in Al-Si *** the present work,the changes in the grain re-finement,mechanical,and casting properties of Al-Si alloys with different Ti concentration levels under various grain refinement conditions were systematically *** specific roles of Ti in the het-erogeneous nucleation ofα-Al grains were summarized,and the formation mechanism of Ti-rich zones in Al-Si alloys was *** Ti concentration could not efficiently reduce the grain size of Al-Si alloys and eventually resulted in inferior mechanical and casting qualities;hence,the recommended Ti concentration level for the aluminum alloy grades of A356 and A357 is≤0.1 wt%.Furthermore,an opti-mized technique for the grain refinement of hypoeutectic Al-Si alloys was presented.A small amount of an Al-TCB master alloy was introduced to achieve the best grain refinement and mechanical properties in a trace Ti *** addition of 0.5 wt%of the Al-TCB master alloy at the Ti concentration level of 0.06 wt%increased the ultimate tensile strength,elongation,and quality index of the Al-7Si-0.45Mg alloy to 328.8±5.0 MPa,14.4%±0.6%,and 970.7±33.1 MPa,respectively.

关键词： Al-Si alloy Titanium Microstructure Grain refinement Mechanical properties

来源：评论

学校读者我要写书评

暂无评论

Tracking Regulatory Mechanism of Trace Fe on Graphene Electromagnetic Wave Absorption

引用

Nano-Micro Letters 2024年第4期16卷 79-96页

作者： Kaili Zhang Yuhao Liu Yanan Liu Yuefeng Yan Guansheng Ma Bo Zhong Renchao Che Xiaoxiao Huang School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China MIIT Key Laboratory of Advanced Structural‑Functional Integration Materials&Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Materials Science and Engineering Harbin Institute of Technology at WeihaiWeihai 264209People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438People’s Republic of China

Polarization and conductance losses are the fundamental dielectric attenuation mechanisms for graphene-based absorbers, but it is not fully understood in revealing the loss mechanism of affect graphene itself. For the first time, the reduced graphene oxide(RGO) based absorbers are developed with regulatory absorption properties and the absorption mechanism of RGO is mainly originated from the carrier injection behavior of trace metal Fe nanosheets on graphene. Accordingly, the minimum reflection loss(RLmin) of Fe/RGO-2composite reaches-53.38 dB(2.45 mm), and the effective absorption bandwidth achieves 7.52 GHz(2.62 mm) with lower filling loading of 2 wt%. Using off-axis electron hologram testing combined with simulation calculation and carrier transport property experiments, we demonstrate here the carrier injection behavior from Fe to graphene at the interface and the induced charge accumulation and rearrangement, resulting in the increased interfacial and dipole polarization and the conductance loss. This work has confirmed that regulating the dielectric property of graphene itself by adding trace metals can not only ensure good impedance matching, but also fully exploit the dielectric loss ability of graphene at low filler content,which opens up an efficient way for designing lightweight absorbers and may be extended to other types materials.

关键词： Reduced graphene oxide Fe nanosheets Dielectric loss Electromagnetic wave absorption

来源：评论

学校读者我要写书评

暂无评论

Vat photopolymerization of silica-based ceramic cores using high solid loading slurry with performance optimization

引用

China Foundry 2025年

作者： Yong-kang Yang Bo-ran Wang Zi-qi Jia Shu-xin Niu Xin Li Ya-jie Guo Xi-qing Xu School of Materials Science and Engineering Chang'an University School of Materials Science and Engineering Key Lab of Advanced Ceramics and Machining Technology of Ministry of Education Tianjin University Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

Vat photopolymerization(VPP) 3D printing is an optimized technology for complex-shaped ceramic cores, in which the solid loading of ceramic slurries greatly influences the microstructure and property of the final ceramic parts. However, the high solid loading of slurries is highly limited by the high viscosity. In this study,silica-based ceramic core slurries with solid loading up to 68vol.% were achieved by the composition design to optimize the performance, considering the curing, rheological, and double bond conversion rate. The slurries demonstrate superior curing and rheological performance with mass ratio of monomers being 3:2 and mass fraction of BYK111 being 4wt.%. Afterwards, the impact of solid loading on the morphology and mechanical properties was investigated. As the solid loading increases, the microstructure becomes gradually dense, leading to an improved flexural strength of 19.5 MPa. Additionally, the sintering shrinkage becomes more uniform,satisfying the casting requirements effectively. This work serves as a guide for the preparation of ceramic slurries with a high solid loading.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Study on the Counter Gravity Adjusted Pressure of Large and Complex Thin-Wall Ni-Based Superalloy Components 75

Study on the Counter Gravity Adjusted Pressure of Large and ...

引用

75th World Foundry Congress, WFC 2024

作者： Sun, Baode Dong, Anping Du, Dafan Xiong, Lianghua He, Lin Sui, Dashan Shanghai Key Lab of Advanced High-Temperature Materials and Precision Forming State Key Lab. of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai200240 China

Counter-gravity casting (CGC) is a widely adopted material processing technique in metals due to its notable benefits, including enhanced filling behavior, reduced defect occurrence, and elevated mechanical properties. It plays a pivotal role in fabricating intricate, high-quality components. Casting experiments and multiscale numerical simulations were conducted to examine the microstructure characteristics of K4169 nickel-based superalloy casting with varying cross-sections during the investment casting process. First, microstructure analysis was conducted on the casting using scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). Moreover, the Cellular Automaton Finite Element method was employed to study the pressure on the dendrite growth and filling behavior in the thin-wall structure. The experimental results revealed that the samples fabricated by counter gravity adjusted pressure investment casting perform finer microstructure and superior mechanical properties. Recently, the CGC was applied to producing large, thin-wall Ni-based superalloy components. Compared to traditional gravity casting, the filling speed, holding pressure, and solidification rate during CGC can be controlled. With a high filling pressure, the defects in the solidification microstructure decreased, and the strength and ductility improved. The large-size CGC facility for large and complex thin-wall Ni-based superalloy components was designed and fabricated in our group;moreover, some representative productions with high quality were successfully made by the large-size CGC facility. © 2024 75th World Foundry Congress, WFC 2024. All rights reserved.

关键词： Investment casting

来源：评论

学校读者我要写书评

暂无评论

Study on the Effect of Static Magnetic Field on the Nickel-Based Superalloy Fabricated by Additive Manufacturing 75

Study on the Effect of Static Magnetic Field on the Nickel-B...

引用

75th World Foundry Congress, WFC 2024

作者： Du, Dafan Dong, Anping Sun, Baode Shanghai Key Lab of Advanced High-Temperature Materials and Precision Forming State Key Lab. of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai200240 China

The influence of a static magnetic field on microstructure evolution during laser direct energy deposition was studied. Our results reveal that dendrite spacing increases with increasing magnetic field flux density (MFFD). Moreover, electron backscatter diffraction results reveal that the epitaxial growth was preferred with increasing MFFD. We discuss these findings in terms of the influence of a magnetic field on melt convection and propose that an applied magnetic field effectively limits Marangoni convection. © 2024 75th World Foundry Congress, WFC 2024. All rights reserved.

关键词： Surface discharges

来源：评论

学校读者我要写书评

暂无评论

Recent progress on photoactive nonprecious transition-metal complexes

引用

Science China Chemistry 2025年第1期68卷 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of TechnologyHefei 230009China State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic MaterialsWuhan UniversityWuhan 430072China School of Chemistry and Chemical Engineering Anhui UniversityHefei 230601China Key Laboratory of Photochemical Conversion and Optoelectronic Materials&CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Photoactive complexes of nonprecious transition metals,mainly including those in the first-row and partially the second-row of the Periodic table of elements,have received increasing attention in view of their low cost and long-term *** are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices,artificial photosynthesis,photocatalysis,biodiagnostics,and therapeutics,*** review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes,including photoactive Zr,V,Cr,Mo,and W complexes,Mn complexes and hybrids,Fe,Co,Ni,and Cu complexes,and Zn and Cd complexes and hybrids.A particular focus is given on the molecular design,modulation of photophysical and photochemical properties,and applications of the representative and lately-developed nonprecious metal *** addition,a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

来源：评论

学校读者我要写书评

暂无评论

Regulation of histidine metabolism by Lactobacillus Reuteri mediates the pathogenesis and treatment of ischemic stroke

引用

Acta Pharmaceutica Sinica B 2025年第1期15卷 239-255页

作者： Kangrui Hu Zhihao Zhou Haofeng Li Jijun Xiao Yun Shen Ke Ding Tingting Zhang Guangji Wang Haiping Hao Yan Liang Key Lab of Drug Metabolism&Pharmacokinetics State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China Ministry of Education Key Laboratory of Protein Science Beijing Advanced Innovation Center for Structural BiologyBeijing Frontier Research Center for Biological StructureTsinghua-Peking Center for Life SciencesSchool of Life SciencesTsinghua UniversityBeijing 100084China School of Materials Science and Engineering Hebei University of Science and TechnologyShijiazhuang 050023China

Increasing evidence has underscored the significance of post-stroke alterations along gutebrain axis,while its role in pathogenesis and treatment of ischemic stroke(IS)remains largely *** study aimed to elucidate the therapeutic effects and action targets of Panax notoginseng saponins(PNS)on IS and explore a novel pathogenesis and treatment strategy of IS via profiling the microbial community and metabolic characteristics along gutebrain *** findings revealed for the first time that the therapeutic effect of PNS on IS was ***/reperfusion(I/R)modeling significantly downregulated Lactobacilli in rats,and PNS markedly recovered Lactobacilli,particularly Lactobacillus reuteri(***).Metabolomics showed a significant reduction in serum histidine(HIS)in clinical obsolete IS patients and rehabilitation period I/R ***,the *** colonization in I/R rats exhibited significant neuroprotective activity and greatly increased HIS in serum,gut microbiota,and ***,exogenous HIS demonstrated indirect neuroprotective effects through metabolizing to ***,vagus nerve severance in I/R rats was performed to investigate HIS’s neuroprotective *** results innovatively revealed that PNS could promote HIS synthesis in gut by enhancing *** proportion,thereby increasing intracerebral HIS through peripheral ***,our data provided novel insights into HIS metabolism mediated by *** in the pathogenesis and treatment of IS.

关键词： Ischemic stroke Inflammation Gut-brain axis Panaxnotoginseng saponins Lactobacillus reuteri Metabolomics Histidine Histamine

来源：评论

学校读者我要写书评

暂无评论

High Temperature Oxidation Behaviours of NiCoCrAlY alloys with High Al Content 9

High Temperature Oxidation Behaviours of NiCoCrAlY alloys wi...

引用

2024 9th International Conference on Mechanical Structures and Smart materials, ICMSSM 2024

作者： Zhang, Jin Ji, Renyi Nie, Zhihua Ning, Xianjin Mu, Rende Tan, Chengwen School of Materials Science and Engineering Beijing Institute of Technology Beijing100081 China Aviat. Key Lab. of Science and Technology on Advanced Corrosion and Protection for Aviation Material AECC Beijing Institute of Aeronautical Materials Beijing100095 China

MCrAlY coatings are of paramount importance in the protection of hot-end components from thermal oxidation and corrosion. The Al content is a crucial factor in enhancing the oxidation resistance properties of the coatings. This paper studies the oxidation behaviors of Ni-27.5Co-17Cr-xAl-0.5Y (x = 12 and 16 wt.%) alloys with high Al content. Following an oxidation process at 1100 °C over a period of 100 h, both alloys exhibit the oxide scales primarily consist of Al2O3 with minor amount of Co(Ni)Al2O4 spinels. The increased Al content results in a higher proportion of β phase, thereby promoting the development of an oxide scale in response to thermal exposure. This study provides insights into the fabrication of high Al content MCrAlY coatings with potential applications in next-generation thermal barrier coatings. © Published under licence by IOP Publishing Ltd.

关键词： Thermal barrier coatings

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：