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Understanding Mass Dependence of Glass Formation in Ring Polymers

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Chinese Journal of Polymer Science 2023年第9期41卷 1447-1461,I0008页

作者： Xiang-Yu Song zhen-yue yang Qi-Lu Yuan Shang-Wei Li Zi-Qiang Tang yue-Tong Dong Shi-Chun Jiang Wen-Sheng Xu State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China School of Materials Science and Engineering Tianjin UniversityTianjin300072China

Having highly tunable molecular topology is one of the most important characteristics of polymers that provides these materials with a wide range of interesting and unique *** particular,ring polymers exhibit a number of properties that are markedly distinct from their linear ***,we compare and contrast the glass formation of unknotted,nonconcatenated ring and linear polymer melts having variable molecular mass based on molecular dynamics simulations of a coarse-grained *** revealing an unusual property in the structure of small rings,we discuss the mass dependence of the structural relaxation time determined from the self-intermediate scattering function over a wide range of temperatures in both ring and linear *** a general trend,we find that the characteristic temperatures(e.g.,the glass transition temperature)and fragility of glass formation increase with increasing molecular mass in linear polymers,but the mass dependences of these properties are rather weak in the family of ring polymer models considered,in broad accord with experimental ***,we show that the glass formation of ring polymers can quantitatively be described by the string model,a model that is broadly consistent with the entropy theory of glass formation and that takes the mass of string-like clusters as a molecular realization of the abstract cooperatively rearranging *** opens the possibility of applying the configurational entropy-based theories to describe the glass formation of ring polymers,once the ring topology is taken into account.

关键词： Ring polymers Glass formation String model Molecular dynamics simulation

Impacts of near-M_(s)austempering treatment on microstructure evolution and bainitic transformation kinetics of a medium Mn steel

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Journal of Iron and Steel Research International 2025年第1期32卷 249-259页

作者： Yong-gang yang Xin-yue Liu Rui-zhi Li Yu-lai Chen Hong-xiang Wu Guo-min Sun zhen-li Mi National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing 100083China Technology Center Ningbo Iron&Steel Co.Ltd.Ningbo 315800ZhejiangChina

The microstructure evolution and bainitic transformation of an Fe-0.19C-4.03Mn-1.48Si steel subjected to near-M_(s)austempering treatment were systematically investigated by combining dilatometer,X-ray diffraction,and electron *** additional austempering treatments with isothermal temperatures above M_(s)were used as *** show that the incubation period for the bainitic transformation occurs when the medium Mn steel is treated with the austempering temperature above M_(s).However,when subjected to near-M_(s)isothermal treatment,the medium Mn steel does not show an incubation period and has the fastest bainitic transformation ***,the largest volume fraction of bainite with a value of 74.7%is obtained on the condition of near-M_(s)austempering treatment after cooling to room *** and microstructure evolution analysis indicates that the elimination of the incubation period and the fastest rate of bainitic transformation are related to the preformed *** advent of preformed martensite allows the specimen to generate more bainite in a limited *** bainitic ferrite nucleation at austenite grain boundaries and through autocatalysis at ferrite/austenite interfaces,a model is established to understand the kinetics of bainite formation and it can describe the nucleation rate of bainitic transformation well when compared to the experimental results.

关键词： Medium manganese steel Bainitic transformation Microstructure Near-M_(s)austempering Transformation modeling

SkullcapflavoneⅡsuppresses TGF-β-induced corneal epithelial mesenchymal transition in vitro

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 209-215页

作者： Meng-Xi Li zhen Zhang yue Zhang Fan-Ru Zhao Yu-Fan Li Yu-Fei Dang yang-yang yue Li Li Department of Ophthalmology The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Xi’an People’s Hospital(Xi’an Fourth Hospital) Shaanxi Eye HospitalAffiliated Xi’an Fourth HospitalNorthwestern Polytechnical UniversityXi’an 710000Shaanxi ProvinceChina Department of Vascular Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina

AIM:To investigate the effect of skullcapflavone II(SCF-II)on the epithelial-mesenchymal transition(EMT)induced by transforming growth factor beta(TGF-β)in human corneal epithelial cells(HCECs),as well as to identify the signaling pathways that may be ***:HCECs were cultured in *** a SCFII(5,10μmol/L)dose,cell viability was analysed with a cell counting kit-8(CCK-8)assay,and cell migration was monitored with wound healing and Transwell migration *** were 4 groups:SCF-II,TGF-β,SCF-II+TGF-βand *** blotting and immunofluorescence were performed to show the expression of EMT markers and the translocation of nuclear factor kappa-B(NF-κB)into the nucleus in the 4 ***:Treatment with SCF-II decreased HCEC viability in a dose-dependent manner.A concentration below 10μmol/L did not present obvious cell toxicity,and survival rates were more than 70%at *** with SCF-II(5 and 10μmol/L)significantly impeded migration in wound healing and Transwell migration assays(P<0.05),and EMT markers and NF-κB translocation into the nucleus were *** both TGF-βand SCF-II treatment,the migration of TGF-β-treated HCECs were suppressed by SCF-II(P<0.05).The expression levels of the mesenchymal markers N-cadherin(P<0.05),α-smooth muscle actin(α-SMA;P<0.05)and NF-κB(P<0.05)in both TGF-β-and SCF-II-treated HCECs were lower than those in the HCECs treated with TGF-βalone and higher than those in HCECs treated with SCF-II *** showed that the entry of NF-κB into the nucleus in both TGF-β-and SCF-IItreated HCECs was less than that in the TGF-β-treated ***:SCF-II inhibit TGF-β-induced EMT in HCECs by potentially regulating the NF-κB signalling ***,SCF-II represents a candidate putative therapeutic agent in corneal fibrotic diseases.

关键词： skullcapflavone II epithelial-mesenchymal transition transforming growth factor nuclear factor kappa-B human corneal epithelial cells

Adsorption removal of mercury from flue gas by metal selenide:A review

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Journal of Environmental Sciences 2025年第2期148卷 420-436页

作者： yang zheng Guoliang Li Yi Xing Wenqing Xu Tao yue School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China CAS Key Laboratory of Green Process and Engineering Institute of Process EngineeringInnovation Academy for Green ManufactureChinese Academy of SciencesBeijing 100190China

Mercury(Hg)pollution has been a global concern in recent decades,posing a significant threat to entire ecosystems and human health due to its cumulative toxicity,persistence,and transport in the *** intense interaction between mercury and selenium has opened up a new field for studying mercury removal from industrial flue gas *** the advantages of good Hg0 capture performance and lowsecondary pollution of the mineral selenium compounds,the most noteworthy is the relatively low regeneration temperature,allowing adsorbent regeneration with low energy consumption,thus reducing the utilization cost and enabling recovery of mercury *** paper reviews the recent progress of mineral selenium compounds in flue gas mercury removal,introduces in detail the different types ofmineral selenium compounds studied in the field ofmercury removal,reviews the adsorption performance of various mineral selenium compounds adsorbents on mercury and the influence of flue gas components,such as reaction temperature,air velocity,and other factors,and summarizes the adsorption mechanism of different fugitive forms of selenium *** on the current research progress,future studies should focus on the economic performance and the performance of different carriers and sizes of adsorbents for the removal of Hg0 and the correlation between the gas-particle flow characteristics and gas phase mass transfer with the performance of Hg0 removal in practical industrial *** addition,it remains a challenge to distinguish the oxidation and adsorption of Hg0 quantitatively.

关键词： Non-conventional pollutants Adsorbents Metal selenides Flue gas Mercury removal

Desymmetrized pillar[8]arenes:High-yield synthesis,functionalization,and host-guest chemistry

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Chinese Chemical Letters 2025年第1期36卷 288-292页

作者： Jie yang Xin-yue Lou Dihua Dai Jingwei Shi Ying-Wei yang College of Chemistry Jilin UniversityChangchun 130012China School of Life Sciences Jilin UniversityChangchun 130012China Department of Laboratory Medicine Center China-Japan Union Hospital of Jilin UniversityChangchun 130033China

The preparation,functionalization,and investigations in host-guest properties of high-level pillararene macrocycles have long been a big challenge because of the lack of efficient synthetic ***,a novel type of pillararene derivative,namely desymmetrized pillar[8]arene(DP[8]A),has been successfully synthesized via a facile two-step strategy with high *** with its pillar[8]arene counterpart,DP[8]A is composed of four alkoxy-substituted benzene units and four bare benzene *** crystal analysis has been performed in order to unveil the molecular conformation and packing mode of DP[8]A,which indicated that DP[8]A possesses a unique chair-like structure and much smaller steric *** functional theory(DFT)calculations and electrostatic potential map suggested the inhomogeneous electronic distribution in the DP[8]A ***-soluble carboxylate-modified DP[8]A,that is,CDP[8]A,was also prepared to investigate the host-guest properties in aqueous solution with methyl viologen(MV),where the binding constant and morphologies of the formed host-guest complexes have been *** all,this new version of eight-membered pillararene derivative might potentially serve as a powerful macrocycle candidate for further applications in supramolecular chemistry.

关键词： Host-guest interaction Macrocycle chemistry Pillararenes Supramolecular chemistry Synthetic macrocycles

Polarization variable terahertz metasurface along the propagation path

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Fundamental Research 2025年第1期5卷 124-131页

作者： Li, Jitao Liu, Jingyu yue, zhen Li, Jie zheng, Chenglong yang, Fan Li, Hui Zhang, Yating Zhang, Yan Yao, Jianquan Key Laboratory of Opto-Electronics Information Technology (Tianjin University) Ministry of Education School of Precision Instruments and Opto-Electronics Engineering Tianjin University Tianjin 300072 China Beijing Key Laboratory for Metamaterials and Devices Key Laboratory of Terahertz Optoelectronics Ministry of Education and Beijing Advanced Innovation Center for Imaging Technology Department of Physics Capital Normal University Beijing 100048 China

Conventional metasurfaces for terahertz polarization are limited to performing lateral (in the x-y plane) polarization control of the output wave. In such cases, the polarization state remains unchanged in each output plane along the propagation path. Herein, we propose a terahertz polarization metasurface that operates longitudinally (i.e., along the z-axis direction of propagation), which modifies the polarization state of each output plane throughout the propagation path. Our designed metasurface can control the phase delays of the left-handed and right-handed circularly polarized (LCP and RCP) components of the incident terahertz wave. This enables the LCP beam and RCP beam to converge to the z-axis through distinct paths, creating a Bessel beam. The proposed design achieved a linearly polarized terahertz wave including both LCP and RCP components with a precise phase difference Δφ at each point within a certain range along the z-axis. The Δφ varies as the propagation distance, resulting in a rotated linearly polarized output wave along the propagation path, while the rotation angle ranges from 0 to π. Based on the variable property of longitudinal polarization, we propose an application concept of dielectric refractive index sensing, in which an additional medium is placed in the terahertz propagation path and the unknown refractive index is determined by detecting the rotation angle of the output polarization state. Theoretically, the device might find potential applications in variable media excitation, terahertz communication, and terahertz radar ranging. © 2023

关键词： Longitudinal polarization Metasurface Polarization manipulation Propagation path Refractive index sensing Terahertz

Metallogenic model of sandstone-hosted copper deposits:a case study from the Paleogene in Jiashi area,northwestern China

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Journal of Palaeogeography 2025年第01期14卷 105-125页

作者： Long-Qing Shi Xing-yue Qu Carlos Zavala yang Li College of Earth Science and Engineering Shandong University of Science and Technology Geology Department Universidad Nacional del Sur Geología de Cuencas Sedimentarias (GCS) Argentina Institute of Energy Peking University Ordos Research Institute of Energy Peking University Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and Technology

Sandstone-hosted copper deposits,a type of Sediment-Hosted Stratiform Copper (SSC) deposits,are widely distributed *** economically viable deposits of SSC are relatively scarce,they account for approximately 30%of the world's total discovered copper ***,there is still a lack of comprehensive and in-depth research into the depositional and metallogenic models of these *** Jiashi area of the Tarim Basin in northwestern China,known for its economically significant Paleogene SSC deposit,lacks in-depth studies on metallogenic *** address this,field profile observations were conducted to analyze the sedimentary evolution,sequence stratigraphy,and tectonism of the Paleogene strata in the Jiashi *** with elemental geochemical analysis of samples,the provenance of sediment,and the source of metallogenic materials,a robust metallogenic model was *** results reveal the influence of provenance for the origin of Paleogene copper-rich *** evolution played a crucial role in controlling the distribution of copper and sulfur elements,as well as the spatial arrangement of metallogenic ***,nappe movement potentially generated faults,allowing upward movement of basin fluids,which played a crucial role in the formation of copper deposits within sandstone-hosted ***,this study offers a comprehensive analysis of the metallogenic processes involved in sandstone-hosted copper deposits,thereby contributing significant insights to the broader research on SSC deposits worldwide.

关键词： Tarim Basin Paleogene Sandstone-hosted copper deposits Metallogenic material source Metallogenic model

Resilient satellite-based PNT system design and key technologies

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Science China Earth Sciences 2025年第3期68卷 669-682页

作者： Yuanxi yang zheng YAO yue MAO Tianhe XU Dixing WANG Key Laboratory of Smart Earth Xi'an Research Institute of Surveying and Mapping Department of Electronic Engineering Tsinghua University School of Space Science and Technology Shandong University

Satellite-based positioning navigation and timing(PNT) system is the most fundamental and convenient application system in PNT fields now and in the future, thus the satellite-based PNT service system should be more and more robust, reliable and easy to be applied. Aiming at the weak service performance of the existing BeiDou constellation in the Antarctic and Arctic regions and the possible discontinuous problems in the autonomous orbit determination using BeiDou terminals on board of low earth orbit(LEO) satellites, we propose a scheme to optimize the BeiDou constellation configuration. A relatively optimized deep space PNT service constellation is designed in order to overcome the weak service capability of the BeiDou navigation constellation in deep space. We find that more satellites in the same orbital plane have better positioning geometry than increasing the number of constellation orbital planes. Furthermore, the idea of resilient satellite-based PNT service mode combining deep, high, medium, and low earth orbit navigation constellations is proposed, in order to improve the service capability of multi navigation constellations. To strengthen the satellite PNT service ability, the resilient strategies of on-board phased array antenna, on-board atomic clocks and satellite signal generator are proposed, in which the adaptively possible adjustment of signal power, signal frequency, signal modulation waveform and information format are discussed. Some examples to demonstrate the resilient satellite-based PNT application modes are given.

关键词： BeiDou navigation constellation Resilient navigation constellation Resilient PNT service Resilient signal modulation Adaptive signal power

Targeting capabilities of engineered extracellular vesicles for the treatment of neurological diseases

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Neural Regeneration Research 2025年第11期20卷 3076-3094页

作者： Xinyu yang Xiangyu Gao Xiaofan Jiang Kangyi yue Peng Luo Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina

Recent advances in research on extracellular vesicles have significantly enhanced their potential as therapeutic agents for neurological *** to their therapeutic properties and ability to cross the blood–brain barrier,extracellular vesicles are recognized as promising drug delivery vehicles for various neurological conditions,including ischemic stroke,traumatic brain injury,neurodegenerative diseases,glioma,and ***,the clinical application of natural extracellular vesicles is hindered by their limited targeting ability and short clearance from the *** address these limitations,multiple engineering strategies have been developed to enhance the targeting capabilities of extracellular vesicles,thereby enabling the delivery of therapeutic contents to specific tissues or ***,this review aims to highlight the latest advancements in natural and targeting-engineered extracellular vesicles,exploring their applications in treating traumatic brain injury,ischemic stroke,Parkinson's disease,Alzheimer's disease,amyotrophic lateral sclerosis,glioma,and ***,we summarized recent clinical trials involving extracellular vesicles and discussed the challenges and future prospects of using targeting-engineered extracellular vesicles for drug delivery in treating neurological *** review offers new insights for developing highly targeted therapies in this field.

关键词： Alzheimer's disease amyotrophic lateral sclerosis engineered extracellular vesicles glioma ischemic stroke neurological diseases Parkinson's disease psychosis targeted drug delivery traumatic brain injury