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Chinese Journal of Polymer Science 2017年第12期35卷 1497-1507页

作者： yi-lan guo Run-zhi Zhang Kai Wu 陈枫傅强 College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University

In this article, hybrid fillers with different dimensions, namely, 2-dimensional（2-D） expanded graphite（EG） and 1-dimensional（1-D） multi-walled carbon nanotubes（CNTs）, were added to aromatic nylon MXD6 matrix via melt-blending, to enhance its thermal and electrical conductivity as well as electromagnetic interference shielding effectiveness（EMI SE）. For ternary composites of MXD6/EG/CNTs, the electrical conductivity reaches up nine orders of magnitude higher compared to that of the neat MXD6 sample, which turned the polymer-based composites from an insulator to a conductor, and the thermal conductivity has been enhanced by 477% compared with that of neat MXD6 sample. Meanwhile, the EMI SE of ternary composite reaches ~50 d B at the overall filler loading of only 18 wt%. This work can provide guidance for the preparation of polymer composites with excellent thermal and electrical conductivity via using hybrid filler.

关键词： Thermal and electrical conductivity Electromagnetic interference shielding Hybrid filler Synergistic effect

Towards High Molecular Weight Poly(bisphenol A carbonate) with Excellent Thermal Stability and Mechanical Properties by Solid-State Polymerization

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Chinese Journal of Polymer Science 2015年第8期33卷 1176-1185页

作者： Yu-ling He yi-lan guo Rui He Tian-xiang Jin 陈枫傅强 Nan Zhou Ji Shen College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University China Bluestar Chengrand Chemical Co. Ltd.

Poly（bisphenol A carbonate）（BPA-PC） was post-polymerized by solid-state polymerization （SSP） after supercritical CO2-induced crystallization in low molecular weight particles prepolymerized via melt transesterification reaction. The effects of the crystallization conditions on melting behavior and SSP of BPA-PC were investigated with differential scanning calorimetry （DSC）, Ubbelohde viscosity method and gel permeation chromatography （GPC）. The reaction kinetics of the SSP of crystallized prepolymers was studied as a function of reaction temperatures for various reaction periods. As a result, the viscosity average molecular weight of BPA-PC particles （2 mm） increased from 1.9 × 10^4 g/mol to 2.8 × 10^4 g/mol after SSP. More importantly, the significantly enhanced thermal stability and mechanical properties of solid-state polymerized BPA-PC, compared with those of melt transesterification polymerized BPA-PC with the same molecular weight, can be ascribed to the substantial avoidance of undergoing high temperature during polymerization. Our work provides a useful method to obtain practical product of BPA-PC with high quality and high molecular weight.

关键词： Poly(bisphenol A carbonate) Solid-state polymerization Supercritical C02-induced crystallization Highmolecular weight High quality.

Laser image refractive index sensor based on the combination of a coreless optical fiber and a digital camera

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Optoelectronics Letters 2025年第2期21卷 65-68页

作者： guo Jingzhong lan Feng CHEN Xiang LIU Haifeng Xi'an Institute of Space Radio Technology Key Laboratory of Optoelectronic Sensor and Sensing Network Technology College of Electronic Information and Optical Engineering Nankai University

As a laser passes through a scattering medium,the light interacts with the irregular reflections within the medium,resulting in light scattering and the formation of *** this paper,an image sensor based on the combination of a coreless optical fiber and a digital camera is proposed for liquid refractive index sensing *** coreless fiber is used as a sensing unit,and the change in the speckle pattern is measured using the digital correlation method to detect the magnitude of the liquid's refractive *** experimental results indicate that the laser image sensing technique is capable of effectively distinguishing liquid samples with refractive indices ranging from 1.332 8 to1.390 8,with a sensing sensitivity of-1.306 ***,the laser image sensing technique,with its advantages of high experimental reproducibility,simple system design,remote over-control,holds great research significance and potential application in laser communication and sensor integration.

关键词： Digital cameras

Multiple Tin Compounds Modified Carbon Fibers to Construct Heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 507-527页

作者： Zhiqiang guo Di lan Zirui Jia Zhenguo Gao Xuetao Shi Mukun He Hua guo Guanglei Wu Pengfei yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China

Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly ***-component interface engineering is considered an effective means to achieve high-efficiency EMW ***,interface modulation engineering has not been fully discussed and has great potential in the field of EMW *** this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal *** utilizing the different properties of different substances,rich heterogeneous interfaces are *** effectively promotes charge transfer and enhances interfacial polarization and conduction *** prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy *** minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 ***,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel ***,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

关键词： Electrostatic spinning Component regulation Heterogeneous interfaces Electromagnetic wave absorption Corrosion protection

The detection, extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 86-96页

作者： Qianyun Yun Wen-Biao Han yi-Yang guo He Wang Minghui Du Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physics and Astronomy Shanghai Jiao Tong University School of Astronomy and Space Science University of Chinese Academy of Sciences Taiji Laboratory for Gravitational Wave Universe (Beijing/Hangzhou) University of Chinese Academy of Sciences lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Province Key Laboratory of Quantum Theory and Applications of MoE Lanzhou University Institute of Theoretical Physics & Research Center of Gravitation Lanzhou University International Centre for Theoretical Physics Asia-Pacific (ICTP-AP) University of Chinese Academy of Sciences (UCAS) Center for Gravitational Wave Experiment National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EMRIs). This task is particularly challenging because EMRI signals are complex, lengthy, and faint. In this work, we introduce a2-layer convolutional neural network(CNN) approach to detect EMRI signals for space-borne detectors, achieving a true positive rate(TPR) of 96.9% at a 1% false positive rate(FPR) for signal-to-noise ratio(SNR) from 50 to 100. Especially, the key intrinsic parameters of EMRIs such as the mass, spin of the supermassive black hole(SMBH) and the initial eccentricity of the orbit can also be inferred directly by employing a neural network. The mass and spin of the SMBH can be determined at 99% and 92% respectively. This will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform model. This study underscores the potential of deep learning methods in EMRI data analysis, enabling the rapid detection of EMRI signals and efficient parameter estimation.

关键词： gravitational wave EMRIs deep-learing

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基于直觉模糊集的企业动态能力测量

系统工程 2016年第12期34卷 135-145页

作者：戴亦兰张卫国华南理工大学工商管理学院广东广州510641 北京师范大学珠海分校国际商学部广东珠海519087

在梳理文献的基础上,首先通过专家调查法筛选出了关于企业动态能力测量的关键指标。然后,利用直觉模糊集的相关理论,将语言短语形式的指标权重、数值和语言短语形式的评价信息转化为直觉模糊数的形式,通过计算方案的综合评价值、群体综... 详细信息

在梳理文献的基础上,首先通过专家调查法筛选出了关于企业动态能力测量的关键指标。然后,利用直觉模糊集的相关理论,将语言短语形式的指标权重、数值和语言短语形式的评价信息转化为直觉模糊数的形式,通过计算方案的综合评价值、群体综合评价值及最终的优势度,获得动态能力评分的排序。文章通过电子商务企业的实例验证了直觉模糊集在动态能力测量的可行性和有效性。

关键词：动态能力直觉模糊集直觉模糊数犹豫度

不同生态系统水分利用效率指标在黄土高原半干旱草地应用的适宜性评价

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植物生态学报 2017年第5期41卷 497-505页

作者：刘晓戚超闫艺兰袁国富中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室北京100101 中国科学院大学资源与环境学院北京100049

对近些年提出的两种生态系统水分利用效率指标——内在水分利用效率(IWUE)和固有水分利用效率(u WUE)与经典的水分利用效率(WUE)指标在黄土高原典型半干旱草地生态系统的应用情况进行了比较,主要分析了不同指标在小时、日和年尺度上的... 详细信息

对近些年提出的两种生态系统水分利用效率指标——内在水分利用效率(IWUE)和固有水分利用效率(u WUE)与经典的水分利用效率(WUE)指标在黄土高原典型半干旱草地生态系统的应用情况进行了比较,主要分析了不同指标在小时、日和年尺度上的一致性和稳定性,并提出优化水分利用效率(o WUE)指标,比较了不同定义的水分利用效率指标在模拟总初级生产力(GPP)逐日动态过程上的表现。结果显示:IWUE和u WUE适合在日和小时尺度分析植被的碳水耦合特征,WUE适合分析年尺度的碳水耦合特征;o WUE指标在描述碳水耦合特征方面与u WUE相比并没有本质性改善,但在用于模拟GPP动态过程时模拟效果改善明显;采用o WUE和u WUE指标能改善植被生长盛期的GPP动态过程模拟,但在生长季早期和晚期的模拟效果比WUE差。IWUE指标不适合模拟GPP动态过程。

关键词：水分利用效率内在水分利用效率固有水分利用效率优化水分利用效率总初级生产力模拟

Exosomes:the next-generation therapeutic platform for ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1221-1235页

作者： Wenjing yin Hongyin Ma Yang Qu Jiaxin Ren yingying Sun Zhen-Ni guo yi Yang Stroke Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina Neuroscience Research Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional ***,there is an urgent need to develop new methods for the treatment of this *** are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological *** have low immunogenicity,good stability,high delivery efficiency,and the ability to cross the blood–brain *** physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic *** rapid development of nanotechnology has advanced the application of engineered exosomes,which can effectively improve targeting ability,enhance therapeutic efficacy,and minimize the dosages *** in technology have also driven clinical translational research on *** this review,we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke,including their antiinflammation,anti-apoptosis,autophagy-regulation,angiogenesis,neurogenesis,and glial scar formation reduction ***,it is worth noting that,despite their significant therapeutic potential,there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified *** optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic ***,our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

关键词： blood–brain barrier electroacupuncture engineering exercise exosomes ischemic stroke mesenchymal stem cells microglia neuroprotection stents

Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

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Neural Regeneration Research 2025年第9期20卷 2598-2610页

作者： yi Wang Yuning Li Yakun Gu Wei Ma Yuying Guan Mengyuan guo Qianqian Shao Xunming Ji Jia Liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment

Regulating crystallization and retarding oxidation in Sn-Pb perovskite via 1D cation engineering for high performance all-perovskite tandem solar cells

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Journal of Energy Chemistry 2025年第1期100卷 646-652页

作者： Ranran Liu Xin Zheng Zaiwei Wang Miaomiao Zeng Chunxiang lan Shaomin Yang Shangzhi Li Awen Wang Min Li Jing guo Xuefei Weng Yaoguang Rong Xiong Li Michael Gr?tzel Center for Mesoscopic Solar Cells Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Institute of Technology for Carbon Neutrality Shenzhen Institute of Advanced Technology Chinese Academy of Sciences School of Physics and Optoelectronic Engineering Hainan University Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO) Chinese Academy of Sciences School of Chemistry Chemical Engineering and Life Sciences State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

All-perovskite tandem solar cells have the potential to surpass the theoretical efficiency limit of single junction solar cells by reducing thermalization ***,the challenges encompass the oxidation of Sn2+to Sn4+and uncontrolled crystallization kinetics in Sn-Pb perovskites,leading to nonradiative recombination and compositional heterogeneity to decrease photovoltaic efficiency and operational ***,we introduced an ionic liquid additive,1-ethyl-3-methylimidazolium iodide （EMIMI） into Sn-Pb perovskite precursor to form low-dimensional Sn-rich/pure-Sn perovskites at grain boundaries,which mitigates oxidation of Sn2+to Sn4+and regulates the film-forming dynamics of Sn/Pb-based perovskite *** optimized single-junction Sn-Pb perovskite devices incorporating EMIMI achieved a high efficiency of 22.87%.Furthermore,combined with wide-bandgap perovskite sub-cells in tandem device,we demonstrate 2-terminal all-perovskite tandem solar cells with a power conversion efficiency of 28.34%,achieving improved operational stability.

关键词： All-perovskite tandem solar cells Sn-Pb perovskite 1D Regulated crystallization Antioxidation