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The electromagnetic response of composition-regulated honeycomb structural materials used for broadband microwave absorption

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Journal of Materials Science & Technology 2021年第29期88卷 203-214页

作者： Huifang pang Yuping Duan Xuhao Dai Lingxi Huang xuan Yang Tuo Zhang Xiaoji Liu Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian116085China

The undesirable absorption bandwidth is the main limitation for the application of microwave absorbing *** that the design of structure and composition of absorbing coating allows it to obtain a satisfying absorption bandwidth and to avoid weight increasing,honeycomb and its sandwich structures coated by various absorbant have been developed and measured using an arch measurement system over2-18 *** further understand the absorption mechanisms of honeycomb structural materials,simulation based on finite element method and transmission line theory is performed to analyze the different responses to the applied microwave between honeycomb structural materials and uniform-medium slab *** proper composition design allows control over the microwave loss mechanisms,which optimize the coating to possess both of the dielectric and magnetic *** the honeycomb structural materials,the magnetic resonation is found for the first time,which is resulting from the periodic honeycomb walls on both sides of the dielectric cavity(consisting of the aramid paper interlayer and vacuum hexagonal prisms).In addition,the conversion of structure from solid to honeycomb brings about changes in impedance,propagating path,effective wavelength,effective attenuation area,microwave phases,and inductive coupling effect,etc.,which result in a better microwave absorbing *** honeycomb sandwich structure coated by CIP/CB/EP with the weight ratio of 4:0.03:1 shows the absorption bandwidth of~9.8 GHz for reflection loss(RL)lower than-10 dB which covers part of the S and C bands and almost the whole X and Ku bands.

关键词： Microwave absorption Structural materials Honeycomb Electromagnetic response

Bio-Inspired Microwave Modulator for High-Temperature Electromagnetic Protection,Infrared Stealth and Operating Temperature Monitoring

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Nano-Micro Letters 2022年第2期14卷 124-135页

作者： xuan Yang Yuping Duan Shuqing Li Huifang pang Lingxi Huang Yuanyuan Fu Tongmin Wang Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116085People’s Republic of China Science and Technology On Power Beam Processes Laboratory AVIC Manufacturing Technology InstituteBeijing 100024People’s Republic of China

High-temperature electromagnetic(EM) protection materials integrated of multiple EM protection mechanisms and functions are regarded as desirable candidates for solving EM interference over a wide temperature *** this work,a novel microwave modulator is fabricated by introducing carbonyl iron particles(CIP)/resin into channels of carbonized wood(C-wood).Innovatively,the spaced arrangement of two microwave absorbents not only achieves a synergistic enhancement of magnetic and dielectric losses,but also breaks the translational invariance of EM characteristics in the horizontal direction to obtain multiple phase discontinuities in the frequency range of 8.2-18.0 GHz achieving modulation of reflected wave radiation ***,CIP/C-wood microwave modulator demonstrates the maximum effective bandwidth of 5.2 GHz and the maximum EM protection efficiency over 97% with a thickness of only 1.5 mm in the temperature range 298-673 ***,CIP/C-wood microwave modulator shows stable and low thermal conductivities,as well as monotonic electrical conductivity-temperature characteristics,therefore it can also achieve thermal infrared stealth and working temperature monitoring in wide temperature *** work provides an inspiration for the design of high-temperature EM protection materials with multiple EM protection mechanisms and functions.

关键词： Microwave modulator Electromagnetic protection High temperatures Temperature monitoring Carbonized wood

窟野河流域次降雨事件下水沙变化特征及其输移过程

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水土保持研究 2025年第2期32卷 52-60页

作者：杨晨佘冬立黄萱河海大学农业科学与工程学院南京211100

[目的]深入分析黄土高原粗沙区流域次降雨事件尺度下水沙动态变化特征及其输移过程,为黄土高原粗沙区流域的水沙管理和调控提供重要科学依据。[方法]以黄土高原中游粗沙多沙区窟野河流域为对象,收集2006—2019年间的160场次降雨事件水... 详细信息

[目的]深入分析黄土高原粗沙区流域次降雨事件尺度下水沙动态变化特征及其输移过程,为黄土高原粗沙区流域的水沙管理和调控提供重要科学依据。[方法]以黄土高原中游粗沙多沙区窟野河流域为对象,收集2006—2019年间的160场次降雨事件水沙数据。通过运用方差分析、水沙关系曲线、滞后分析等方法,比较位于窟野河及其子流域次降雨事件下产流输沙特征,构建了各流域次降雨事件尺度下水沙关系曲线,分析了水沙滞后关系及滞后指数的空间差异,以揭示次降雨尺度下窟野河流域的水沙输移过程。[结果](1)4个流域径流相关参数无显著差异,但泥沙相关参数差异显著;(2)位于窟野河上游东部的新庙流域水沙相关性强,表征外界人为干扰的参数(a)最大,位于上游西部的王道恒塔流域泥沙浓度低,水沙相关性弱,表征河流本身输沙能力的参数(b)最大;(3)新庙、王道恒塔和温家川3个流域的主要滞后模式为逆时针型,泥沙来源于上游区域,且高含沙降雨事件的滞后系数(HI)平均值多为负;而神木流域的主要滞后模式为“8”字型,指示泥沙来源相对接近流域出口,且高含沙降雨事件的HI平均值多为正。[结论]窟野河嵌套流域次降雨事件尺度下水沙变化空间差异显著,泥沙输移过程复杂,不同子流域滞后模式揭示了泥沙来源和输移机制的空间异质性。

关键词：次降雨事件尺度输移过程水沙关系滞后分析

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艾渣不同极性部位的体外抗氧化活性

香料香精化妆品 2018年第5期 27-32,35页

作者：黄梅胡璇庞玉新闻庆于福来陈振夏中国热带农业科学院热带作物品种资源研究所/农业部华南作物基因资源与种质创制重点开放实验室海南儋州571737

为考察艾渣不同极性溶剂提取部位的体外抗氧化活性,用紫外分光光度法对以石油醚、氯仿、乙酸乙酯、正丁醇和水为溶剂的5个不同极性部位萃取物中总黄酮含量进行测定,并以抗坏血酸(VC)为阳性对照,采用DPPH、ABTS自由基清除法和Fe^(3+)还原... 详细信息

为考察艾渣不同极性溶剂提取部位的体外抗氧化活性,用紫外分光光度法对以石油醚、氯仿、乙酸乙酯、正丁醇和水为溶剂的5个不同极性部位萃取物中总黄酮含量进行测定,并以抗坏血酸(VC)为阳性对照,采用DPPH、ABTS自由基清除法和Fe^(3+)还原法(FRAP法)测定艾渣不同极性部位的体外抗氧化作用。结果表明,艾渣中黄酮类物质偏中等极性,多富集于乙酸乙酯及氯仿部位。艾渣提取物的不同极性部位均有不同程度的体外抗氧化效果。其中乙酸乙酯部位的DPPH及ABTS自由基清除率最强[IC_(50)值分别为(0.115±0.003) g/L和(0.093±0.003) g/L],正丁醇及氯仿部位的DPPH及ABTS自由基清除率次之。水层还原Fe^(3+)的能力最强,其次为正丁醇与乙酸乙酯部位。石油醚部位在三个抗氧化试验中均表现出较弱的抗氧化性。因此,初步推测抗氧化活性多集中于乙酸乙酯与正丁醇部位,可以将其作为抗氧化剂添加到化妆品中。

关键词：艾渣极性部位总黄酮含量抗氧化活性

Development and characterization of novel microsatellite markers for the Common Pheasant(Phasianus colchicus)using RAD-seq

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Chinese Birds 2017年第1期8卷 63-69页

作者： Biao Wang xuan Xie Simin Liu Xuejing Wang Hong pang Yang Liu State Key Laboratory of Biocontrol College of Ecology and Evolution/School of Life SciencesSun Yat-sen UniversityGuangzhou 510275China

Background: The Common Pheasant(Phasianus colchicus) Linnaeus, 1758 is the most widespread pheasant in the world and widely introduced as a game bird. Increasing needs for conservation genetics and management of both wild and captive populations require permanent genetic resources, such as polymorphic microsatellites in order to genotype individuals and ***: In this study, 7598 novel polymorphic microsatellites for the Common Pheasant were isolated using a RAD-seq approach at an Illumina high-throughput sequencing platform. A panel of ten novel microsatellites and three existing ones from the chicken genome were multiplexed and genotyped on a set of 90 individuals of Common Pheasants(representing nine subspecies and ten individuals each) and 10 individuals of the Green Pheasant(P. versicolor).Results: These 13 microsatellites exhibited moderate to high levels of polymorphism, with the number of alleles per locus ranging from 2 to 8 and expected heterozygosities from 0.049 to 0.905. The first analysis of the genetic structure of subspecies/populations using a Bayesian clustering approach, implemented in STRUCTURE, showed two genetic clusters, corresponding to both the Green and the Common Pheasant, with further evidence of subpopulation structuring within the Common ***: These markers are useful genetic tools for sustainable uses and evolutionary studies in these two Phasianus pheasants and probably other closely related game birds.

关键词： Population structure Game bird Restocking RAD-seq Hybridization

1株变异伪狂犬病病毒的分离鉴定及gE和TK基因序列分析

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中国兽医学报 2020年第4期40卷 695-701页

作者：万曾培庞旋飞王征帆伍建敏李中圣王贵平白挨泉佛山科学技术学院广东佛山528231 广东海大畜牧兽医研究院广东广州511400

为了探索伪狂犬病病毒(PRV)流行株的基因变异及遗传演变规律,本试验对福建福州疑似发生猪伪狂犬病的猪场病料,首先选用PCR技术、小鼠接种试验、细胞接种试验及间接免疫荧光鉴定等方法分离鉴定病原,再对病原进行毒价测定、TK和gE基因克... 详细信息

为了探索伪狂犬病病毒(PRV)流行株的基因变异及遗传演变规律,本试验对福建福州疑似发生猪伪狂犬病的猪场病料,首先选用PCR技术、小鼠接种试验、细胞接种试验及间接免疫荧光鉴定等方法分离鉴定病原,再对病原进行毒价测定、TK和gE基因克隆及序列比对分析。结果显示,病原为PRV野毒,命名为PRV-FJFZ株;PRV-FJFZ株TCID50为10-7.2/0.1 mL,LD50为10-3.56/0.1 mL,对比分析PRV-FJFZ与国外PRV参考毒株的TK和gE基因序列同源性发现,核苷酸的同源性分别为99.5%~100.0%和99.8%~99.9%。TK和gE基因遗传进化树表明,PRV-FJFZ株与当前国内流行的变异PRV毒株在同一分支上,PRV-FJFZ株与国外PRV参考毒株在不同的分支上。本研究结果可为我国PRV的防控净化工作和疫苗株的筛选提供理论依据。

关键词：猪伪狂犬病病毒分离鉴定序列分析 gE基因 TK基因遗传变异

The dynamic compressive properties of magnetorheological plastomers: enhanced magnetic-induced stresses by non-magnetic particles

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Journal of Materials Science & Technology 2022年第7期102卷 195-203页

作者： Haoming pang Zhenbang Xu Longjiang Shen Jun Li Junshuo Zhang Zhiyuan Li Shouhu xuan Xinglong Gong CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsCAS Center for Excellence in Complex System MechanicsUniversity of Science and Technology of China(USTC)Hefei 230027China Anhui Weiwei Rubber Parts Group Co.Ltd Tongcheng 231400China CAS Key Laboratory of On-orbit Manufacturing and Integration for Space Optics System Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Hunan Bogie Engineering Research Center Zhuzhou 412000China

In this research, a series of hollow glass powder(HGP) reinforced magnetorheological plastomers(MRPs)were prepared to improve the impact resistance of the materials, and the dynamic compressive properties of MRPs under high strain rate were investigated by using a split Hopkinson pressure bar(SHPB)system equipped with a customized magnetic device. Experimental results showed the HGPs greatly enhanced the yield stresses of the MRPs. Especially, for MRPs with 9 vol.% carbonyl iron powders(CIPs), the magnetic-induced yield stress increased from 7.3 MPa to 17.1 MPa(134% increased) by adding 18 vol.%HGPs. The particle structures in MRPs were further simulated and the corresponding intergranular stress was calculated to study the enhancement effect of HGPs. The simulated results showed that more compact structures were formed with the excluded volume caused by secondary HGPs, so the yield stresses of the MRPs increased under a magnetic field. However, when the mass ratio of HGP to CIP was larger than 0.67, HGPs would hinder the formation of chain-like structures and reduce the magneto-mechanical properties. As a result, the replacing of CIPs by HGPs was proven to be an excellent strategy to improve the dynamic properties of MRPs.

关键词： Particle-reinforced composites Stress/strain curves Microstructures Impact behavior Mechanical properties

Development of chromatographic fingerprint for quality analysis of diploid and tetraploid Lonicera japonica

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Journal of Traditional Chinese Medicine 2020年第1期40卷 73-82页

作者： Hu xuan Wang Dan pang Yuxin Wu Zhisheng Huan Hengfu Chen Zhijian Li Weidong Institute of Tropical Crop Genetic Resources Chinese Academy of Tropical Agriculture SciencesDanzhou 571737China School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing 100102China

OBJECTIVE:To develop the chromatographic fingerprint of Lonicera japonica(***)and evaluate the effects of polyploidy on the quality of ***:High-performance liquid chromatography(HPLC)methods used to establish the chromatographic fingerprint were *** quality of 11 batches of diploid *** and 13 batches of tetraploid *** collected from different regions across China were *** contents of five active compounds,consisting of chlorogenic acid,rutin,galuteolin,isochlorogenic acid A and quercetin,were further detected in ***:The chromatographic fingerprint established by the optimized HPLC method was verified for qualitative analysis of *** analysis showed that the contents of chlorogenic acid,isochlorogenic acid A,and quercetin in tetraploid plants were higher than those in diploid plants,whereas rutin and galuteolin contents in tetraploid plants were lower than those in diploid ***:The developed HPLC method is suitable for qualitative analysis of *** was indicated to influence the chemical properties of *** *** shows potential for utilization as a medicinal plant with different active components.

关键词： Lonicera Polyploidy Chromatography,high pressure liquid Dermatoglyphics Phytochemicals Qualitative research

Tryptophan metabolism and piglet diarrhea: Where we stand and the challenges ahead

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Animal Nutrition 2024年第2期17卷 123-133页

作者： xuan Zhao Jiaman pang Wanghong Zhang Xie Peng Zhenguo Yang Guangdong Bai Yaoyao Xia College of Animal Science and Technology Southwest University Yunnan Vocational College of Agriculture

The intestinal architecture of piglets is vulnerable to disruption during weaning transition and leads to diarrhea, frequently accompanied by inflammation and metabolic disturbances(including amino acid metabolism). Tryptophan(Trp) plays an essential role in orchestrating intestinal immune tolerance through its metabolism via the kynurenine, 5-hydroxytryptamine, or indole pathways, which could be dictated by the gut microbiota either directly or indirectly. Emerging evidence suggests a strong association between piglet diarrhea and Trp metabolism. Here we aim to summarize the intricate balance of microbiota-host crosstalk by analyzing alterations in both the host and microbial pathways of Trp and discuss how Trp metabolism may affect piglet diarrhea. Overall, this review could provide valuable insights to explore effective strategies for managing piglet diarrhea and the related challenges.

关键词： Tryptophan metabolism Piglet Diarrhea Intestinal microbiota Inflammatory response