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Functionally graded structure of a nitride-strengthened Mg_(2)Si-based hybrid composite
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作者 Jeongho Yang Woongbeom Heogh +15 位作者 Hogi Ju Sukhyun Kang Tae-Sik Jang Hyun-Do Jung Mohammad Jahazi Seung Chul Han Seong Je Park Hyoung Seop Kim Susmita Bose Amit Bandyopadhyay Martin Byung-Guk Jun Young Won Kim Dae-kyeom Kim Rigoberto CAdvincula Clodualdo Aranas Jr Sang Hoon Kim 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1239-1256,共18页
The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in orde... The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in order to provide ultimate wear resistance based on the laser-irradiation-induced inclusion of N_(2) gas during laser powder bed fusion.This is substantialized based on both the thermal diffusion-and chemical reactionbased metallurgy of the Mg_(2)Si–SiC/nitride hybrid composite.This study also proposes a functional platform for systematically modulating a functionally graded structure and modeling build-direction-dependent architectonics during additive manufacturing.This strategy enables the development of a compositional gradient from the center to the edge of each melt pool of the Mg_(2)Si–SiC/nitride hybrid composite.Consequently,the coefficient of friction of the hybrid composite exhibits a 309.3%decrease to–1.67 compared to–0.54 for the conventional nonreinforced Mg_(2)Si structure,while the tensile strength exhibits a 171.3%increase to 831.5 MPa compared to 485.3 MPa for the conventional structure.This outstanding mechanical behavior is due to the(1)the complementary and synergistic reinforcement effects of the SiC and nitride compounds,each of which possesses an intrinsically high hardness,and(2)the strong adhesion of these compounds to the Mg_(2)Si matrix despite their small sizes and low concentrations. 展开更多
关键词 Laser powder bed fusion Mg_(2)Si-SiC/nitride hybrid composite Both the thermal diffusion-and chemical reaction-based metallurgy functionally graded structure compositional gradient Wear resistance.
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Tree structure and diversity shape the biomass of primary temperate mountain forests 被引量:2
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作者 Dheeraj Ralhan Ruffy Rodrigo +14 位作者 Heather Keith Annemiek Irene Stegehuis Jakob Pavlin Yumei Jiang Milos Rydval Juliana Nogueira Alexandre Fruleux Marek Svitok Martin Mikolas Daniel Kozak Martin Dusatko Pavel Janda Oleh Chaskovsky Catalin-Constantin Roibu Miroslav Svoboda 《Forest Ecosystems》 SCIE CSCD 2024年第4期568-579,共12页
Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of ... Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of live and dead biomass.Yet,little is known about the interactions between biomass stocks,tree genus diversity and structure across a temperate montane primary forest.Here,we investigated the relationship between tree structure(variability in basal area and tree size),genus-level diversity(abundance,tree diversity)and biomass stocks in temperate primary mountain forests across Central and Eastern Europe.We used inventory data from726 permanent sample plots from mixed beech and spruce across the Carpathian Mountains.We used nonlinear regression to analyse the spatial variability in forest biomass,structure,and genus-level diversity and how they interact with plot-level tree age,disturbances,temperature and altitude.We found that the combined effects of genus and structural indices were important for addressing the variability in biomass across different spatial scales.Local processes in disturbance regimes and uneven tree age support forest hete rogeneity and the accumulation of live and dead biomass through the natural regeneration,growth and decay of the forest ecosystem.Structural complexities in basal area index,supporte d by genus-level abundance,positively influence total biomass stocks,which was modulated by tree age and disturbances.Spruce forests showed higher tree density and basal area than mixed beech forests,though mixed beech still contributes significantly to biomass across landscapes.Forest heterogeneity was strongly influenced by complexities in forest composition(tree genus diversity,structure).We addressed the importance of primary forests as stable carbon stores,achieved through structure and diversity.Safeguarding such ecosystems is critical for ensuring the stability of the primary forest,carbon store and biodiversity into the future. 展开更多
关键词 Biodiversity indicators Biomass carbon stock Ecosystem functioning Forest composition Primary forest structure Tree size distribution
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Effects of an attached functionally graded layer on the electromechanical behaviors of piezoelectric semiconductor fibers 被引量:1
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作者 Kai FANG Nian LI +3 位作者 Peng LI Zhenghua QIAN V.KOLESOV I.KUZNETSOVA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2022年第9期1367-1380,共14页
In this paper,we propose a specific two-layer model consisting of a functionally graded(FG)layer and a piezoelectric semiconductor(PS)layer.Based on the macroscopic theory of PS materials,the effects brought about by ... In this paper,we propose a specific two-layer model consisting of a functionally graded(FG)layer and a piezoelectric semiconductor(PS)layer.Based on the macroscopic theory of PS materials,the effects brought about by the attached FG layer on the piezotronic behaviors of homogeneous n-type PS fibers and PN junctions are investigated.The semi-analytical solutions of the electromechanical fields are obtained by expanding the displacement and carrier concentration variation into power series.Results show that the antisymmetry of the potential and electron concentration distributions in homogeneous n-type PS fibers is destroyed due to the material inhomogeneity of the attached FG layer.In addition,by creating jump discontinuities in the material properties of the FG layer,potential barriers/wells can be produced in the middle of the fiber.Similarly,the potential barrier configuration near the interface of a homogeneous PS PN junction can also be manipulated in this way,which offers a new choice for the design of PN junction based devices. 展开更多
关键词 piezoelectric semiconductor(PS) functionally graded(FG)material composite structure PN junction
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Seeing the macro in the micro:a diffusion model-based approach for style transfer in cellular images
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作者 Jiayi CAI Yong HE +2 位作者 Feng LIU Byung-Ho KANG Xuping FENG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第6期609-612,共4页
The internal structures of cells as the basic units of life are a major wonder of the microscopic world.Cellular images provide an intriguing window to help explore and understand the composition and function of these... The internal structures of cells as the basic units of life are a major wonder of the microscopic world.Cellular images provide an intriguing window to help explore and understand the composition and function of these structures.Scientific imagery combined with artistic expression can further expand the potential of imaging in educational dissemination and interdisciplinary applications. 展开更多
关键词 interdisciplinary applications artistic expression diffusion model explore understand composition function cellular images educational dissemination style transfer internal structures
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湘江下游河库复合生境鱼类群落结构及功能多样性研究
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作者 高易阳 杨政飞 +4 位作者 余建波 向建国 谭禹 黄艳飞 李德亮 《水生态学杂志》 北大核心 2026年第1期140-150,共11页
分析湘江河库复合生境的鱼类群落结构和功能多样性,评估梯级电站对鱼类多样性的影响程度和机制,为湘江鱼类多样性保护与恢复提供科学依据。2017、2022—2024年对湘江下游河库复合生境的株洲(流水)、湘潭(过渡区)和长沙江段(库区)进行鱼... 分析湘江河库复合生境的鱼类群落结构和功能多样性,评估梯级电站对鱼类多样性的影响程度和机制,为湘江鱼类多样性保护与恢复提供科学依据。2017、2022—2024年对湘江下游河库复合生境的株洲(流水)、湘潭(过渡区)和长沙江段(库区)进行鱼类资源调查,比较3个江段的鱼类种类组成和多样性,分析确定3个江段渔获物组成的差异及关键种类。结果显示,夏季和冬季共采集到土著鱼类6 088尾,共4目13科80种,优势种类为鲴类、鳊、鲂、鲌类、鲢、鳙和鮈类;株洲、湘潭、长沙3个江段分别有鱼类67、53和47种,株洲和长沙江段种类相似性系数最低,长沙种类多样性指数最低;3个江段鱼类都以定居性、产粘性卵、广适型鱼类为主,从株洲至长沙江段定居性鱼类、产粘性和沉性卵鱼类、广适型和湖沼型鱼类的比例增加,亲流水型鱼类种数在株洲江段最高;食性以动物食性和肉食性种类最多。株洲江段与另2个江段鱼类群落结构具有显著性差异(P<0.05),聚类分析表明有3个组群,株洲江段的关键种为黄尾鲴、大眼华鳊、细鳞鲴、银鮈、大鳍半鲿、蛇鮈,湘潭江段的为鲂、拟尖头鲌、鳊、大鳍半鲿、细鳞鲴,在长沙和湘潭江段2022年冬季为拟尖头鲌、银鮈、鲂、蛇鮈、细鳞鲴、短颌鲚和鳊,这些种类都是广适型短距离洄游鱼类或产粘性卵的鱼类;从株洲到长沙鱼类功能丰富度下降,功能分散指数增加,功能均匀度和分异指数相似。 展开更多
关键词 梯级电站 复合生境 鱼类群落结构 功能多样性 生态类型 湘江下游
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鸡蛋壳膜酶解物/壳聚糖复合薄膜的制备及性能表征
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作者 李欣怡 吴夏泠 +2 位作者 刘群 翁武银 张玉苍 《食品工业科技》 北大核心 2026年第2期297-307,共11页
基于鸡蛋壳膜制备抗菌抗氧化功能的薄膜,既能作为食品保鲜材料减少经济损失,也可提高鸡蛋壳废弃物的综合利用价值。本研究利用生物酶水解鸡蛋壳膜,研究水解条件对酶解液溶菌酶活力和DPPH·清除率的影响,将蛋壳膜酶解液冷冻干燥获得... 基于鸡蛋壳膜制备抗菌抗氧化功能的薄膜,既能作为食品保鲜材料减少经济损失,也可提高鸡蛋壳废弃物的综合利用价值。本研究利用生物酶水解鸡蛋壳膜,研究水解条件对酶解液溶菌酶活力和DPPH·清除率的影响,将蛋壳膜酶解液冷冻干燥获得的冻干物(Enzymolysis of egg shell membrane,E-ESM)与壳聚糖复合制备活性包装薄膜,研究E-ESM对壳聚糖薄膜结构和性能的影响,并将该薄膜应用于草莓保鲜试验。结果表明:9 U/mg碱性蛋白酶在50℃下酶解4 h后,蛋壳膜酶解液有2.26 U/mL的溶菌酶活力和38.23%的DPPH·清除率;E-ESM和壳聚糖以3:5(v:v)的比例制备的薄膜表现出良好的机械性能(拉伸强度11.32 MPa,断裂伸长率11.75%)、紫外光阻隔能力(紫外光透过率42%)、水蒸气透过率((8.89±0.6)×10^(-11) g·m/(m^(2)·s·Pa))、氧气透过率((2.12±0.6)×10^(-5) g·mm/(m^(2)·s))、对金黄色葡萄球菌和大肠杆菌的抑制率分别是83.33%和80.85%、生物相容性中细胞存活率均在90%以上。在24℃贮藏8 d后,实验组的失重率(29.06%)较对照组降低15.43%、丙二醛含量(911.78µmol/L)较对照组降低6.96%、V_(C)含量(57.27 mg/100 g)较对照组保留74.82%,pH(3.77)和糖度(11.03°Brix),结果表明复合薄膜能够有效延长草莓货架期4~6 d,具有作为活性食品包装薄膜的潜力。 展开更多
关键词 蛋壳膜 酶解 溶菌酶 复合薄膜 结构性能 草莓保鲜
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Development and applications of functional gene microarrays in the analysis of the functional diversity,composition,and structure of microbial communities 被引量:10
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作者 Zhili HE Joy DVAN NOSTRAND +1 位作者 Ye DENG Jizhong ZHOU 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2011年第1期1-20,共20页
Functional gene arrays(FGAs)are a special type of microarrays containing probes for key genes involved in microbial functional processes,such as biogeochemical cycling of carbon,nitrogen,sulfur,phosphorus,and metals,b... Functional gene arrays(FGAs)are a special type of microarrays containing probes for key genes involved in microbial functional processes,such as biogeochemical cycling of carbon,nitrogen,sulfur,phosphorus,and metals,biodegradation of environmental contaminants,energy processing,and stress responses.GeoChips are considered as the most comprehensive FGAs.Experimentally established probe design criteria and a computational pipeline integrating sequence retrieval,probe design and verification,array construction,data analysis,and automatic update are used to develop the GeoChip technology.GeoChip has been systematically evaluated and demonstrated to be a powerful tool for rapid,specific,sensitive,and quantitative analysis of microbial communities in a high-throughput manner.Several generations of GeoChip have been developed and applied to investigate the functional diversity,composition,structure,function,and dynamics of a variety of microbial communities from different habitats,such as water,soil,marine,bioreactor,human microbiome,and extreme ecosystems.GeoChip is able to address fundamental questions related to global change,bioenergy,bioremediation,agricultural operation,land use,human health,environmental restoration,and ecological theories and to link the microbial community structure to environmental factors and ecosystem functioning. 展开更多
关键词 functional gene arrays(FGAs) GeoChip microbial communities functional diversity/composition/structure environmental factor ecosystem functioning
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Plant functional trait diversity and structural diversity co-underpin ecosystem multifunctionality in subtropical forests 被引量:6
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作者 Shuai Ouyang Mengmeng Gou +8 位作者 Pifeng Lei Yue Liu Liang Chen Xiangwen Deng Zhonghui Zhao Yelin Zeng Yanting Hu Changhui Peng Wenhua Xiang 《Forest Ecosystems》 SCIE CSCD 2023年第2期153-161,共9页
Tree species diversity is assumed to be an important component in managing forest ecosystems because of effects on multiple functions or ecosystem multifunctionality.However,the importance of tree diversity in determi... Tree species diversity is assumed to be an important component in managing forest ecosystems because of effects on multiple functions or ecosystem multifunctionality.However,the importance of tree diversity in determining multifunctionality in structurally complex subtropical forests relative to other regulators(e.g.,soil microbial diversity,stand structure,and environmental conditions)remains uncertain.In this study,effects of aboveground(species richness and functional and structural diversity)and belowground(bacterial and fungal diversity)biodiversity,functional composition(community-weighted means of species traits),stand structure(diameter at breast height and stand density),and soil factors(pH and bulk density)on multifunctionality(including biomass production,carbon stock,and nutrient cycling)were examined along a tree diversity gradient in subtropical forests.The community-weighted mean of tree maximum height was the best predictor of ecosystem multifunctionality.Functional diversity explained a higher proportion of the variation in multifunctionality than that of species richness and fungal diversity.Stand structure-played an important role in modulating the effects of tree diversity on multifunctionality.The work highlights that species composition and maximizing forest structural complexity are effective strategies to increase forest multifunctionality while also conserving biodiversity in the management of multifunctional forests under global environmental changes. 展开更多
关键词 Abiotic and biotic factors BIODIVERSITY functional composition functional traits Soil microbial diversity Stand structure
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A partition of unity level set method with moving knot CS-RBFs for optimizing variable stiffness composites 被引量:2
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作者 Gen LI Ye TIAN +2 位作者 Kang YANG Tielin SHI Qi XIA 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第4期565-572,共8页
A partition of unity level set method with moving knot Compactly Supported Radial Basis Functions(CS-RBFs)is proposed for optimizing variable stiffness composite structures.The iso-contours of a level set function are... A partition of unity level set method with moving knot Compactly Supported Radial Basis Functions(CS-RBFs)is proposed for optimizing variable stiffness composite structures.The iso-contours of a level set function are utilized to represent the curved fiber paths,and the tan-gent vector of the iso-contour defines the orientation of fiber.The level set function of the full design domain is constructed according to the Partition of Unity(POU)method by a set of local level set functions defined on an array of overlapping subdomains,and they are constructed by using the CS-RBFs.The positions of knots are iteratively changed during the optimization to improve the performance of composite structures.Several examples of compliance minimization are presented. 展开更多
关键词 Composite structures Moving knots Partition of unity Radial basis functions Structural optimization
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PREPARATION OF POLYSTYRENE/SiO_2 COMPOSITE NANOPARTICLES BEARING SULFONIC GROUPS ON THE SURFACE VIA EMULSION COPOLYMERIZATION USING A POLYMERIZABLE EMULSIFIER
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作者 于建 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第5期629-637,共9页
Functionalized PS/SiO_2 composite nanoparticles bearing sulfonic groups on the surface were successfully synthesized via emulsion copolymerization using a polymerizable emulsifierαolefin solfonate(AOS).As demonstrate... Functionalized PS/SiO_2 composite nanoparticles bearing sulfonic groups on the surface were successfully synthesized via emulsion copolymerization using a polymerizable emulsifierαolefin solfonate(AOS).As demonstrated by transmission electron microscopy and atomic force microscopy,well-defined core-shell PS/SiO_2 composite nanoparticles with a diameter of 50 nm were obtained.Sulfonic groups introduced onto the surface of the composite nanoparticles were quantified by FTIR,and can be controlled to some exten... 展开更多
关键词 PS/SiO_2 composite nanoparticles Polymerizable emulsifier Core-shell structure Sulfonic functionalization.
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Strain concentration factor of heterogeneous materials and analytical influence functions based on Eshelby tensor
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作者 Shanqiao Huang Zifeng Yuan 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第4期306-313,共8页
In this manuscript,Eshelby tensor is employed to assess the strain concentration that arises in the matrix phase at the interface,offering precise values and locations of maximum strain under specific loading conditio... In this manuscript,Eshelby tensor is employed to assess the strain concentration that arises in the matrix phase at the interface,offering precise values and locations of maximum strain under specific loading conditions for both spherical and cylindrical inclusions.When compared to numerical simulation results,the analytical predictions grounded in the Eshelby tensor exhibit satisfactory accuracy.Then an analytical calculation method based on Eshelby tensor for the elastic strain influence functions of reduced-order homogenization(ROH)method is developed and adopted on particle-reinforced and fibrous composites,presenting its feasibility and advantage on off-line stage calculation of ROH method.The error analyses between analytical and numerical results are conducted.The numerical results also exhibit the necessity of finer interface partitioning to obtain the response on micro-scale with higher resolution. 展开更多
关键词 Eshelby tensor Strain concentration Composite structures Reduced-order-homogenization Influence functions
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Influence of Nanocrystalline Structure on Wear and Corrosion Behavior of Al-SiC<sub>P</sub>Composite
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作者 Jagannati Venumurali Gaddam Bhanodaya Reddy 《Journal of Minerals and Materials Characterization and Engineering》 2020年第2期47-58,共12页
Functionally graded (FG) Al-SiCP composites fabricated via centrifugal casting are widely used in automobile components particularly a brake rotor disc be-cause of its high SiC fraction at the outer periphery. However... Functionally graded (FG) Al-SiCP composites fabricated via centrifugal casting are widely used in automobile components particularly a brake rotor disc be-cause of its high SiC fraction at the outer periphery. However, when operated in corrosive environment like road deicing salts the disc is highly sensitive to the corrosion due to high SiC fraction. But, the nanocrystalline (NC) structured surfaces synthesized by severe plastic deformation (SPD) method have excel-lent wear and corrosion resistance at the surface. Therefore, shot peening (SP) as a SPD method conducted on one side of the stir casted FG Al composite having 10 wt% SiCP constant reinforcement in order to create NC structured surface. The SP treatment continued for 70 s and 140 s durations. Thereafter, the surface characteristics of the composite before and after SP were estimated by XRD and then the composites were tested by wear and corrosion tests. The results revealed that the SP for 140 s duration favors the induction of hardened layer, higher grain refinement (NC structure) and dislocation density which promotes the occurrence of high surface hardness, thus significantly improving its wear properties. However, higher dislocation density resulted from longer duration shown deterioration to the corrosion resistance. Whereas, the attained degree of NC structure is more pronounced over dislocation density resulted after 70 s SP duration, thereby composite showed excellent corrosion re-sistance. Thus, the composite with 70 s duration possessed excellent corrosion and relatively good wear properties too. 展开更多
关键词 functionally Graded Al-SiCP COMPOSITE Shot PEENING NC structure WEAR Corrosion
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Function-Integrative Textile Reinforced Concrete Shells
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作者 Sandra Gelbrich Henrik L. Funke Lothar Kroll 《Open Journal of Composite Materials》 2018年第4期161-174,共14页
This paper presents the development and technological implementation of textile reinforced concrete (TRC) shells with integrated functions, such as illumination and light control. In that regard the establishment of m... This paper presents the development and technological implementation of textile reinforced concrete (TRC) shells with integrated functions, such as illumination and light control. In that regard the establishment of material, structural and technological foundations along the entire value chain are of central importance: From the light-weight design idea to the demonstrator and reference object, to the technological implementation for the transfer of the research results into practice. The development of the material included the requirement-oriented composition of a high-strength fine grained concrete with an integrated textile reinforcement, such as carbon knitted fabrics. Innovations in formwork solutions provide new possibilities for concrete constructions. So, a bionic optimized shape of the pavilion was developed, realized by four connected TRC-lightweight-shells. The thin-walled TRC-shells were manufactured with a formwork made of glass-fibre reinforced polymer (GFRP). An advantage of the GFRP-formwork is the freedom of design concerning the formwork shape. Moreover, an excellent concrete quality can be achieved, while the production of the precast concrete components is simple and efficient simultaneously. After the production the new TRC-shells were installed and assembled on the campus of TU-Chemnitz. A special feature of the research pavilions are the LED light strips integrated in the shell elements, providing homogeneous illumination. 展开更多
关键词 TEXTILE REINFORCED CONCRETE Carbon REINFORCED CONCRETE TEXTILE REINFORCED Composites function-Integrated Lightweight structures Glass-Fibre REINFORCED Polymer FORMWORK Thin-Walled SHELLS
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高频变压器多层共振复合吸声结构优化与设计
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作者 陈彬 沈辰轩 +3 位作者 张涛 刘洋 靳艳娇 万妮娜 《高电压技术》 北大核心 2025年第11期5648-5660,I0030,共14页
大容量高频变压器通常处于高频方波电压激励下,大量的电压谐波分量会造成高频变压器铁芯振动过程中含有大量的高阶振动分量,进而引起高次谐波处声压级显著增大,造成严重的噪声污染。为此,该文首先设计了一种新型多层共振复合吸声结构,... 大容量高频变压器通常处于高频方波电压激励下,大量的电压谐波分量会造成高频变压器铁芯振动过程中含有大量的高阶振动分量,进而引起高次谐波处声压级显著增大,造成严重的噪声污染。为此,该文首先设计了一种新型多层共振复合吸声结构,基于传递矩阵法对比分析了6种不同吸声结构的吸声性能;然后建立了高频变压器电磁-结构-声三维仿真模型,分析了高频变压器加与未加复合吸声装置下声场分布特性;在此基础上,采用中心组合试验设计与有限元仿真相结合的方法,获得吸声装置在不同结构参数下的声场仿真结果,通过构建径向基神经网络模型来预测声压级,并利用全局灵敏度分析技术研究吸声装置结构参数对声压级水平的影响程度;最后,基于融合正余弦和柯西变异的麻雀搜索优化算法,获得了吸声装置最优设计参数并通过仿真验证。结果表明:优化后的吸声结构噪声抑制效果显著,相比未优化前声压级水平降低10.176 dB,验证了多层共振复合吸声结构对高频变压器具有较好的抑噪效果。 展开更多
关键词 电磁-结构-声场分析 多层共振复合吸声结构 高频变压器 径向基神经网络 全局灵敏度分析
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以学生为中心的超大型高校规划布局模式探索——以河南师范大学科技创新港校区为例 被引量:1
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作者 劳燕青 林诗意 汪扬 《建筑与文化》 2025年第7期23-25,共3页
随着我国高等教育从精英型向大众型转变,超大型大学校园的规划面临诸多挑战。文章以“以学生为中心”的规划理念为出发点,通过对国内典型超大型校园规划案例的分析,揭示了当前超大型校园在功能分区以及校园交通方面存在的问题。进而,以... 随着我国高等教育从精英型向大众型转变,超大型大学校园的规划面临诸多挑战。文章以“以学生为中心”的规划理念为出发点,通过对国内典型超大型校园规划案例的分析,揭示了当前超大型校园在功能分区以及校园交通方面存在的问题。进而,以河南师范大学科技创新港校区为例,提出了一种以学生为中心的超大型校园规划设计模式。该模式通过引入环状功能结构、复合型功能模式及步行化校园设计策略,构建一个生态、便捷、学术氛围浓厚的校园环境。 展开更多
关键词 以学生为中心 超大型校园 校园规划 复合型功能 环状结构
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不同类型黄腐酸的性质表征 被引量:1
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作者 武国寒 文新月 +4 位作者 王亚玲 梅秀文 陈克岩 牛秋红 王秀斌 《中国土壤与肥料》 北大核心 2025年第3期223-232,共10页
探究矿物源黄腐酸(MFA)、生化源黄腐酸(BFA)和秸秆源黄腐酸(SFA)的结构差异,为黄腐酸在农业生产中的应用提供合理依据。采用元素分析仪(EA)、紫外-可见光谱(UV-Vis)、傅里叶红外光谱(FTIR)、核磁共振碳谱(^(13)C-NMR)、三维荧光光谱(3D-... 探究矿物源黄腐酸(MFA)、生化源黄腐酸(BFA)和秸秆源黄腐酸(SFA)的结构差异,为黄腐酸在农业生产中的应用提供合理依据。采用元素分析仪(EA)、紫外-可见光谱(UV-Vis)、傅里叶红外光谱(FTIR)、核磁共振碳谱(^(13)C-NMR)、三维荧光光谱(3D-EEMs)和气相色谱-质谱联用(GC/MS)等技术,研究不同类型黄腐酸的元素组成、官能团种类、化学结构特征及化合物组成。元素组成显示,SFA中O、S、N、H元素含量均高于MFA和BFA,且具有较高的H/C、O/C、N/C和(N+O)/C。采用UV-Vis和FTIR发现,与MFA相比,BFA和SFA的芳香性较弱,芳香环上的含氧官能团较多,分子量较小,聚合度程度低。采用^(13)C-NMR表明,3类黄腐酸的碳结构均以烷氧基碳和芳香碳占比为主,但SFA的疏水性指数、芳香缩合程度低于MFA和BFA。采用3D-EEMs显示,3类黄腐酸在组成物质上均以羰基、羧基和酚类结构的含氧类物质为主,其中SFA和BFA的羧基、羰基和酚类结构占比较大,而MFA的芳香性结构则较多。采用GC/MS发现,MFA、BFA和SFA分别由84、93和101种化合物组成,且均以含氧化合物为主,其占比分别为89.89%、92.80%和86.28%,而含氮化合物则是SFA高于MFA和BFA。总之,不同类型黄腐酸的元素含量、含氧官能团、化学结构特征及化合物组成存在较大差异,其中SFA具有更多的含氮、含氧官能团及化合物组成,分子量较小、芳香性较弱,活性更强,是MFA和BFA的良好替代产品。 展开更多
关键词 黄腐酸 元素组成 官能团 化学结构 化合物组成
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多元纤维复合吸波材料设计及电磁性能研究进展 被引量:1
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作者 朱国松 陈伊 +5 位作者 胡悦 张钦钊 黄佳 周伟 罗衡 李杨 《航空材料学报》 北大核心 2025年第4期1-13,共13页
随着信息安全、目标隐身与电磁防护等需求的升级,亟需研发高效吸波材料。本文简述吸波材料工作原理,并梳理涂覆型与结构型吸波材料研究进展,最终聚焦纤维混杂吸波复合材料的发展:纤维排列、组分调控及界面设计可协同提升电磁性能与力学... 随着信息安全、目标隐身与电磁防护等需求的升级,亟需研发高效吸波材料。本文简述吸波材料工作原理,并梳理涂覆型与结构型吸波材料研究进展,最终聚焦纤维混杂吸波复合材料的发展:纤维排列、组分调控及界面设计可协同提升电磁性能与力学性能。通过多元纤维协同设计与多尺度结构优化,纤维混杂吸波复合材料能够实现阻抗匹配与损耗机制的耦合优化,兼具宽频吸收与力学承载特性,推动吸波材料向结构与功能一体化方向发展。最后,总结通过多元纤维混杂体系拓展吸波频带的技术突破并对未来围绕纤维混杂机制深化、多尺度结构设计、环境适应性提升、多功能集成、纤维取向与入射角协同调控、高温陶瓷基吸波材料等方向开发兼具宽频吸收、轻质高强特性的新一代军民两用吸波材料进行展望。 展开更多
关键词 涂覆型与结构型吸波材料 纤维混杂复合材料 电磁损耗 结构与功能一体化
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葵花籽蛋白的组成、提取、功能特性及其应用的研究进展
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作者 史方丹 周际松 +7 位作者 吴萍 邵家起 邓乾春 肖军霞 金伟平 邓紫玙 向霞 彭登峰 《中国粮油学报》 北大核心 2025年第7期223-234,共12页
向日葵是我国的特色油料作物之一,我国葵花籽年产量约174万t,位居世界第四。葵花籽中含有丰富的蛋白质(质量分数19.0%~27.1%)和脂肪(质量分数32.0%~51.6%),且其脂肪酸组成以油酸、亚油酸等不饱和脂肪酸为主。制油是葵花籽的主要加工用... 向日葵是我国的特色油料作物之一,我国葵花籽年产量约174万t,位居世界第四。葵花籽中含有丰富的蛋白质(质量分数19.0%~27.1%)和脂肪(质量分数32.0%~51.6%),且其脂肪酸组成以油酸、亚油酸等不饱和脂肪酸为主。制油是葵花籽的主要加工用途之一,压榨后得到的饼粕中含有大量的蛋白质,质量分数约30%~50%,且葵花籽蛋白的必需氨基酸含量丰富,比例相对均衡,其在人体内的真实回肠消化率为85.6%,是一种优质植物蛋白,但目前葵花籽饼粕主要用做饲料和肥料,其所含蛋白质的高值化利用潜力远未被挖掘。为了提升葵花籽蛋白的有效利用率,本文首先总结了葵花籽蛋白的组成、结构和营养价值,然后归纳了葵花籽蛋白的提取方法及功能特性,并总结了修饰改性对其功能特性的影响,最后,概述了葵花籽蛋白在食品中的应用潜力。 展开更多
关键词 葵花籽蛋白 组成 营养价值 结构 制备 功能特性
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界面工程策略赋能纤维增强树脂基复合材料研究进展
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作者 陈茗 史芷丞 +1 位作者 陈凤翔 徐卫林 《高分子学报》 北大核心 2025年第12期2246-2261,共16页
纤维增强树脂基复合材料因其轻质高强、耐腐蚀性强、热稳定性与绝缘性高、可设计性与加工灵活等优势,已成为航空航天、国防军工、汽车和轨道交通、能源、基础设施等领域的关键材料.本综述首先从纤维的结构特点、性能优势和应用领域出发... 纤维增强树脂基复合材料因其轻质高强、耐腐蚀性强、热稳定性与绝缘性高、可设计性与加工灵活等优势,已成为航空航天、国防军工、汽车和轨道交通、能源、基础设施等领域的关键材料.本综述首先从纤维的结构特点、性能优势和应用领域出发,系统总结了代表性高性能无机纤维和有机纤维的优势,通过分析其差异,凝练出共性问题,即高表面化学惰性所导致的与树脂界面相容性差.针对上述难题,本文探讨了界面调控机制及相应解决策略,综述了先进的界面处理技术及其国内外研究进展,并从新型树脂材料的开发、发展低成本和智能化制造技术、结构-功能一体化设计与应用、发展循环回收再利用新技术、人工智能与复合材料的深度耦合等几个方面展望了纤维增强树脂基复合材料未来的发展趋势,以期为推动该材料体系的进一步发展提供新思路. 展开更多
关键词 高性能纤维 界面调控策略 纤维增强树脂基复合材料 结构功能一体化
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复合材料结构电池在民用飞机中的应用
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作者 李星 楼旸 +3 位作者 董嘉琪 徐吉峰 吴海宏 石伟峰 《北京航空航天大学学报》 北大核心 2025年第12期4093-4105,共13页
复合材料结构电池能够使传统复合材料结构在满足承载功能的同时,具备电存储性能,是实现民用飞机结构功能一体化的途径之一。复合材料结构电池的研究现状及性能指标表明,其结构刚度效率和结构强度效率约为60%,储能效率约为50%。复合材料... 复合材料结构电池能够使传统复合材料结构在满足承载功能的同时,具备电存储性能,是实现民用飞机结构功能一体化的途径之一。复合材料结构电池的研究现状及性能指标表明,其结构刚度效率和结构强度效率约为60%,储能效率约为50%。复合材料结构电池可优先用于向飞机厨房系统和客舱娱乐系统供电,待技术进一步提升后可用于向客舱环控系统、机翼电防除冰等系统供电;复合材料结构电池布置首选客舱地板、厨房和盥洗室结构件,其次可选择翼身整流罩、机翼/尾翼后缘舱等结构。对于复合材料结构电池应用于民用飞机结构的有利条件和不利因素进行了综合对比分析,典型应用场景下复合材料结构电池可实现结构减重和燃油节约的效益,同时也会带来制造成本、检查维护成本、地面充电/基础设施建设成本的增加。复合材料结构电池应用于民用飞机也对客舱防火技术和电池热管理技术带来了新的挑战。 展开更多
关键词 复合材料 结构电池 储能结构 民机应用 结构功能一体化
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