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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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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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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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不同类型黄腐酸的性质表征
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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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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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聚芳撑树脂基结构/功能一体化复合材料制备与性能研究
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作者 赵陆翔 房强 +2 位作者 白彦江 戴鑫 张鹏飞 《固体火箭技术》 北大核心 2025年第4期616-623,共8页
针对固体发动机结构功能一体化发展趋势和需求,以主链为全芳基的新型聚芳撑树脂为基体、以T700碳纤维为增强体,研制了一种兼具结构承载能力和烧蚀防护功能的高性能复合材料。采用旋转流变仪和差示扫描量热仪分析了聚芳撑树脂的流变特性... 针对固体发动机结构功能一体化发展趋势和需求,以主链为全芳基的新型聚芳撑树脂为基体、以T700碳纤维为增强体,研制了一种兼具结构承载能力和烧蚀防护功能的高性能复合材料。采用旋转流变仪和差示扫描量热仪分析了聚芳撑树脂的流变特性和固化行为;利用NOL环测试方法表征了新型聚芳撑树脂与碳纤维的界面性能;制备了聚芳撑树脂基结构/功能一体化复合材料∅200 mm标准试验容器,并完成了水压爆破测试。结果表明,聚芳撑树脂基结构/功能一体化复合材料的氧乙炔线烧蚀率≤0.10 mm/s;容器爆破压强为32.0 MPa,这与T700/环氧复合材料体系基本相当。 展开更多
关键词 聚芳撑树脂 结构/功能一体化 固体发动机 复合材料
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基于干法分离工艺提取豌豆蛋白及其功能性质 被引量:1
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作者 贺雅琳 邓阳 +1 位作者 刘延峰 刘潇 《食品科学》 北大核心 2025年第10期216-221,共6页
以环境友好为导向,保留豌豆蛋白天然结构为目标,基于研磨和气流分级进行豌豆蛋白干法分离,得到富含蛋白质豌豆细组分(蛋白组分)和富含淀粉豌豆粗组分(淀粉组分)。结果表明,在气流分级机转速10 000 r/min下分离制备的蛋白组分的蛋白质量... 以环境友好为导向,保留豌豆蛋白天然结构为目标,基于研磨和气流分级进行豌豆蛋白干法分离,得到富含蛋白质豌豆细组分(蛋白组分)和富含淀粉豌豆粗组分(淀粉组分)。结果表明,在气流分级机转速10 000 r/min下分离制备的蛋白组分的蛋白质量分数达54.16%;与豌豆粉和淀粉组分相比,蛋白组分凝胶储能模量(G’)明显更高;与湿法分离商品化豌豆蛋白相比,干法分离豌豆蛋白中的清蛋白(26 kDa)未流失,蛋白天然结构完整保留。此外,在pH 3~7范围内,蛋白溶解度均显著高于商品化蛋白,pH 7时干法分离豌豆蛋白的溶解度达86%。本研究结果可为绿色、高效制备低变性高品质豌豆蛋白提供参考和理论支撑。 展开更多
关键词 干法分离 豌豆蛋白 绿色提取 结构组成 功能特性
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紫苏籽蛋白开发利用研究进展
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作者 武峥明 黄亚文 +5 位作者 邓乾春 唐小倩 陈尚文 彭登峰 陈亚淑 邓紫玙 《中国油料作物学报》 北大核心 2025年第6期1361-1372,共12页
紫苏籽是我国特色油料作物,制油后的饼粕中蛋白含量可达45%。紫苏籽蛋白氨基酸组成丰富、比例适合人体吸收,真实消化率达到94.2%,显示出做为优质天然蛋白的巨大潜力。然而紫苏籽蛋白资源往往被忽视,仅用于低价值的动物饲料、肥料或直接... 紫苏籽是我国特色油料作物,制油后的饼粕中蛋白含量可达45%。紫苏籽蛋白氨基酸组成丰富、比例适合人体吸收,真实消化率达到94.2%,显示出做为优质天然蛋白的巨大潜力。然而紫苏籽蛋白资源往往被忽视,仅用于低价值的动物饲料、肥料或直接被丢弃,未能充分发挥其潜在价值。为提高紫苏籽蛋白的利用效率,本文对紫苏籽蛋白的组成和结构及营养价值进行了概述,系统总结了紫苏籽蛋白的提取方法和功能特性,以及修饰改性对其功能特性的优化。此外,本文还探讨了紫苏籽蛋白在食品中的多种应用,旨在为紫苏籽蛋白的深入开发研究提供参考。 展开更多
关键词 紫苏籽蛋白 组成 结构 营养价值 提取 功能特性 修饰改性
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