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Nano Materials Science 2022年第2期4卷 133-138页

作者： Liping Zhou Peng Xu Faxiang Qin Institute for Composites Science Innovation(InCSI) School of Materials Science and EngineeringZhejiang University38 Zheda RoadHangzhou310027PR China

Next-generation packaging materials are expected to have higher thermal conductivity,because the heat accumulated in high-performance electronic equipment should be removed to increase the service life of the equipment.At the same time,the dielectric loss of the material needs to be reduced to lessen signal delay and attenuation,especially for the applications under high frequency.In this work,we introduce nano-silicon carbide(SiC)and carbon nanotubes(CNTs)into the polystyrene(PS)and poly(methyl methacrylate)(PMMA)blends system.The design of two-way migration at the interface of CNTs and SiC nanoparticles is realized through the masterbatch method and processing technology control.As a result,the thermal conductivity is successfully increased up to 75%.Meanwhile,compared to the CNTs single-phase migration system,it effectively reduces the dielectric loss of the nanocomposite and optimizes the electrical insulation.This work has significant practical application value in the design of electronic device substrates and packaging materials,and provides an innovative methodology for the mesostructure design of multiphase nanocomposites.

关键词： Immiscible blends Nanocomposite Microwave dielectric properties Thermal conductivity

Boosting Interfacial Polarization Through Heterointerface Engineering in MXene/Graphene Intercalated-Based Microspheres for Electromagnetic Wave Absorption

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Nano-Micro Letters 2023年第9期15卷 436-460页

作者： Ge Wang Changfeng Li Diana Estevez Peng Xu Mengyue Peng Huijie Wei Faxiang Qin Institute for Composites Science Innovation(InCSI) School of Materials Science and EngineeringZhejiang University38 Zheda RoadHangzhou 310027People’s Republic of China Ningbo Institute of Technology Zhejiang University1 Qianhu South RdNingbo 315100People’s Republic of China Foshan(Southern China)Institute for New Materials FoshanPeople’s Republic of China

Multi-layer 2D material assemblies provide a great number of interfaces beneficial for electromagnetic wave absorption.However,avoiding agglomeration and achieving layer-by-layer ordered intercalation remain chal-lenging.Here,3D reduced graphene oxide(rGO)/MXene/TiO_(2)/Fe_(2)C lightweight porous microspheres with periodical intercalated structures and pronounced inter-facial effects were constructed by spray-freeze-drying and microwave irradiation based on the Maxwell–Wagner effect.Such approach reinforced interfacial effects via defects introduction,porous skeleton,multi-layer assembly and multi-compo-nent system,leading to synergistic loss mechanisms.The abundant 2D/2D/0D/0D intercalated heterojunctions in the microspheres provide a high density of polari-zation charges while generating abundant polarization sites,resulting in boosted interfacial polarization,which is verified by CST Microwave Studio simulations.By precisely tuning the 2D nanosheets intercalation in the heterostructures,both the polarization loss and impedance matching improve significantly.At a low filler loading of 5 wt%,the polarization loss rate exceeds 70%,and a minimum reflection loss(RLmin)of-67.4 dB can be achieved.Moreover,radar cross-section simulations further confirm the attenuation ability of the optimized porous microspheres.These results not only provide novel insights into understanding and enhancing interfacial effects,but also constitute an attractive platform for implementing heterointerface engineering based on customized 2D hierarchical architectures.

关键词： MXene Hierarchical microspheres Interfacial polarization Spray-freeze-drying Microwave absorption

Extra-wide bandwidth via complementary exchange resonance and dielectric polarization of sandwiched FeNi@SnO_(2)nanosheets for electromagnetic wave absorption

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Journal of Materials Science & Technology 2021年第31期90卷 1-8页

作者： Huipeng Lv Chen Wu Faxiang Qin Huaxin Peng Mi Yan School of Materials Science and Engineering State Key Laboratory of Silicon MaterialsZhejiang UniversityHangzhou310027China

Advanced electromagnetic(EM)wave absorbers with wide bandwidth is crucial to avoid EM interference and radiation,while achieving compensatio nal attenuation at different frequencies is challe nging.Herein,two-dimensional(2 D)sandwiched FeNi@SnO_(2)have been designed,for which SnO_(2)nanosheets provide numerous heterogeneous nucleation sites for the growth of dispersive FeNi nanoparticles with reduced size.The SnO_(2)exhibits dipole polarization at 21.45 GHz with a width of~4.00 GHz,while the FeNi nanoparticles induce excha nge resonance at 18.13 GHz(~6.00 GHz width)and interfacial polarization at15.97 GHz(~6.00 GHz width).Such complementary attenuation mechanisms give rise to an impressive ultra-wide effective absorption bandwidth of 11.70 GHz with strong absorption of-49.1 dB at a small thickness of 1.75 mm.Not only superior EM wave absorption is achieved in this work,it also provides a versatile strategy to integrate different loss mechanisms in the design of EM wave absorbers with extra-wide bandwidth.

关键词： Sandwiched FeNi@SnO_(2)nanosheets Dielectric polarization Exchange resonance Complementary attenuation Electromagnetic wave absorption

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素化复合材料概念及设计

复合材料学报 2020年第2期37卷 237-241页

作者：李钰涵秦发祥浙江大学材料科学与工程学院

材料"素化"为降低金属材料的合金化程度及资源回收利用的难度提供了一个简洁且具有应用前景的设计方法。本文将素化的概念引入复合材料中,提出在不改变材料体系基本组成、不增加功能相体积分数的前提下,以复合材料的多级结构设计(如界... 详细信息

材料"素化"为降低金属材料的合金化程度及资源回收利用的难度提供了一个简洁且具有应用前景的设计方法。本文将素化的概念引入复合材料中,提出在不改变材料体系基本组成、不增加功能相体积分数的前提下,以复合材料的多级结构设计(如界面工程、缺陷工程等)为核心,充分利用多级结构的调控能力,实现材料性能的提高及综合性能的优化。以典型复合材料体系为基础,分析将素化的概念应用于复合材料体系的可行性、优势及预期结果,并根据前期研究说明多级结构的设计方法及应用基础。以碳纳米管(CNT)/硅橡胶(SE)复合材料的界面实践为例,展示了素化设计在可重构微波吸收复合材料中的应用。

关键词：素化复合材料多级结构界面优化

The hydrothermal changes of permafrost active layer and their impact on summer rainfall-runoff processes in an alpine meadow watershed,northwest China

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Research in Cold and Arid Regions 2022年第6期14卷 361-369页

作者： Jia qin YongJian Ding TianDing Han YaPing Chang faxiang Shi YanHui You State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Eco-hydrology Inland River Basin Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China

The freezing-thawing variation of permafrost active layer increases the complexity of rainfall-runoff processes in alpine river basins,Northwest China.And alpine meadow is the prominent ecosystem in these basins.This study selected a small alpine meadow watershed in the upper reaches of the Shule River Basin,China.We investigated alpine rainfall-runoff processes,as well as impacts of summer thaw depth of active layer,soil temperature and moisture variation on streamflow based on in-situ observations from July 2015 to December 2020.Some hydrologic parameters or indices were calculated using statistical methods,and impacts of permafrost change on river runoff were assessed using the variable infiltration capacity model(VIC).In the alpine meadow,surface soil(0–10 cm depth)of the active layer starts to freeze in mid-October each year,and begins to thaw in early April.Also,the deeper soil(70–80 cm depth)of the active layer starts to freeze in late October,and begins to thaw in late June.Moisture content in shallow soils fluctuates regularly,whereas deeper soils are more stable,and their response to rainstorms is negligible.During active layer thawing,the moisture content increases with soil depth.In the alpine meadow,vertical infiltration only occurred in soils up to 40 cm deep,and lateral flow occurred in0–20 and 60–80 cm deep soils at current rainfall intensity.Summer runoff ratios were 0.06–0.31,and runoff floods show lags of 9.5–23.0 h following the rainfall event in the study area.The freeze–thaw process also significantly impacts runoff regression coefficients,which were 0.0088–0.0654 per hour.Recession coefficient decrease negatively correlates with active layer thawing depth in summer and autumn.Alpine river basin permafrost can effectively increase peak discharge and reduce low flow.These findings are highly significant for rainfall–runoff conversion research in alpine areas of inland rivers.

关键词： Rainfall-runoff process Alpine meadow Permafrost active layer Northwest China

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基于功能纤维的超复合材料设计理念（英文）

中国材料进展 2019年第4期38卷 319-340页

作者：秦发祥 Diana Estevez 彭华新浙江大学材料科学与工程学院功能复合材料与结构研究所

超材料由于在微波器件、完美镜片和电磁隐身等多方面的应用潜力,引起了很多关注。典型的传统超材料可以金属线和开口环以周期性结构构建而成。然而,这种设计的尺寸太小,并且不适用于基于超材料的大规模应用。在这篇综述中,我们将展示一... 详细信息

超材料由于在微波器件、完美镜片和电磁隐身等多方面的应用潜力,引起了很多关注。典型的传统超材料可以金属线和开口环以周期性结构构建而成。然而,这种设计的尺寸太小,并且不适用于基于超材料的大规模应用。在这篇综述中,我们将展示一种特殊类型的超材料,我们称为超复合材料:即具有超材料特性的纤维增强的复合材料。其中重点讲述了磁性微丝阵列使役的超复合材料及其在复合材料构件的结构健康监测、雷达天线罩中的频率选择性响应等一系列工程场景中的典型应用示例。在这种超复合材料中,负磁导率是由铁磁共振引起的,负介电常数是由等离子体响应实现的,等离子体响应由添加相的尺寸和拓扑结构等几何参数决定。该种材料在简化设计、实现面内各向同性性能以及应力、磁场和电流驱动的性能可调性方面具有优势。此外,可以通过调控纤维填料在组成、长度、直径的本征特征、进行后处理、或者与其他材料进行混杂等方式进行优化设计,以实现最佳的调谐能力,从而实现预期的应用。除了聚焦超复合材料设计理念之外,还详尽阐述了自动化制造过程和制备出来的材料的结构性能,以期获得真正实用的多功能复合材料。

关键词：超材料超复合材料负介电常数负磁导率透射窗口磁性纤维阵列磁性纤维复合材料

Air–water CO2 flux in an algae bloom year for Lake Hongfeng,Southwest China:implications for the carbon cycle of global inland waters

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Acta Geochimica 2017年第4期36卷 658-666页

作者： faxiang Tao State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of Sciences99Lincheng West RoadGuanshanhu DistrictGuiyang 550081GuizhouChina

The carbon cycle of global inland waters is quantitatively comparable to other components in the global carbon budget. Among inland waters, a significant part is man-made lakes formed by damming rivers. Manmade lakes are undergoing a rapid increase in number and size. Human impacts and frequent algae blooms lead to it necessary to make a better constraint on their carbon cycles. Here, we make a primary estimation on the air–water CO_2 transfer flux through an algae bloom year for a subtropical man-made lake—Hongfeng Lake, Southwest China. To do this a new type of glass bottles was designed for content and isotopic analysis of DIC and other environmental parameters. At the early stage of algae bloom,CO_2 was transferred from the atmosphere to the lake with a net flux of 1.770 g·C·m^(-2). Later, the partial pressure(pCO_2) of the aqueous CO_2 increased rapidly and the lake outgassed to the atmosphere with a net flux of 95.727 g·C·m^(-2). In the remaining days, the lake again took up CO_2 from the atmosphere with a net flux of 14.804 g·C·m^(-2). As a whole, Lake Hongfeng released 4527 t C to the atmosphere, accounting for one-third of the atmosphere/soil CO_2 sequestered by chemical weathering in the whole drainage. With an empirical mode decomposition method, we found air temperature plays a major role in controlling water temperature, aqueous pCO_2 and hence CO_2 flux. This work indicates a necessity to make detailed and comprehensive carbon budgets in man-made lakes.

关键词： CO2 flux Algae bloom Carbon cycle Inland waters Lake Hongfeng

激光等离子烧结Ni-Mn-Ga/Cu磁热复合材料的大热导率和强力学性能

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Science China Materials 2023年第9期66卷 3670-3680页

作者：张一弛高岩 Victorino Franco 尹航博策彭华新秦发祥 Institute for Composites Science Innovation(InCSI) School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Condensed Matter Physics ICMS-CSICUniversity of SevilleP.O.Box 106541080 SevillaSpain School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

基于磁热效应的磁制冷技术可以更好满足能源高效消耗和转化的要求.以工程化视角来看,制备磁热复合材料是结合理想磁热性能、高热导率和良好力学性能的有效方式.在本文中,采用激光等离子烧结技术(SPS)制备了Ni-Mn-Ga/Cu磁热复合材料,并... 详细信息

基于磁热效应的磁制冷技术可以更好满足能源高效消耗和转化的要求.以工程化视角来看,制备磁热复合材料是结合理想磁热性能、高热导率和良好力学性能的有效方式.在本文中,采用激光等离子烧结技术(SPS)制备了Ni-Mn-Ga/Cu磁热复合材料,并将其与利用传统方式制备的材料进行了对比.本文详细研究了Ni-Mn-Ga/Cu的磁学性质,发现其磁热效应优于热压烧结及微米/纳米化的对应材料体系.同时,该磁热复合材料具有11.2 W m^(-1)K^(-1)的优良热导率.本文使用Hasselman–Johnson模型并对其进行优化,探究了热导率与复合材料微观组织的关系.与电弧炉熔炼样品相比,不同SPS烧结温度制备的磁热复合材料的力学水平得到提高,其最小断裂应力和断裂应变分别为340 MPa和4%.此外,利用基于拓展线性Drucker–Prager模型的有限元模拟方法,阐明了Ni-Mn-Ga/Cu磁热复合材料的失效机制.以上实验和模拟结果丰富了磁热材料领域的相关知识,并促进了磁制冷技术面向实际应用的进一步发展.

关键词：电弧炉熔炼断裂应变失效机制 Johnson模型磁制冷技术断裂应力磁热效应等离子烧结

基于横桥向孔道偏差的预制T梁侧弯变形量分析研究

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公路工程 2019年第5期44卷 31-35,98页

作者：秦发祥邬晓光丁杰黄叙钦长安大学公路学院陕西西安710018 中国人民武装警察部队第二机动总队福建福州350000

针对预制T梁在施工阶段发生梁体侧弯变形的问题,通过走访调研,理论公式推导计算和依托关中地区某制梁场建立的104组数值模型,对比分析不同孔道偏位量下梁体的侧弯变形量和变化趋势,得出50m及50m以下预制T梁,其梁体侧弯变形量与孔道偏位... 详细信息

针对预制T梁在施工阶段发生梁体侧弯变形的问题,通过走访调研,理论公式推导计算和依托关中地区某制梁场建立的104组数值模型,对比分析不同孔道偏位量下梁体的侧弯变形量和变化趋势,得出50m及50m以下预制T梁,其梁体侧弯变形量与孔道偏位量之间呈线性相关关系,中梁孔道偏差允许值为10mm,边梁孔道偏差允许值为8mm,侧弯变形量仅和孔道偏位量有关,与钢束在梁高方向位置无关的结论。通过该研究为进一步规范装配式T梁桥预制施工奠定基础,为推进规范填补关于孔道偏位横桥向允许偏差提供参考。

关键词：桥梁工程 T梁侧弯变形量横桥向孔道偏差

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高觉敷的文化自信思想及其时代价值

心理学探新 2023年第2期43卷 112-116页

作者：郑发祥江西师范大学心理学院南昌330022

高觉敷文化自信思想根源于其早年的国学教育以及后来对革命文化与社会主义先进文化的不断学习,萌芽于西方心理学著作翻译中的中西文化碰撞,确立于中国心理学史的系统性研究和建设中国特色心理学体系的构想。高觉敷文化自信思想的本质内... 详细信息

高觉敷文化自信思想根源于其早年的国学教育以及后来对革命文化与社会主义先进文化的不断学习,萌芽于西方心理学著作翻译中的中西文化碰撞,确立于中国心理学史的系统性研究和建设中国特色心理学体系的构想。高觉敷文化自信思想的本质内涵在于:与社会主义先进文化的共性与特性的有机结合,与革命文化的理想与实践的完美融合,与传统文化的批判与继承的辩证统一。高觉敷文化自信思想具有重要的历史意义和时代价值。

关键词：高觉敷文化自信思想时代价值