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Microstructural evolution and mechanical properties of a new Al-Cu-Li-X alloy at different solution temperatures

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Rare Metals 2021年第3期40卷 635-642页

作者： Long Zhang Zi-Qiao Zheng Jin-Feng Li cheng-yu tan Yong-Lai Chen Xu-Hu Zhang School of Materials Science and Engineering Central South UniversityChangsha 410083China Aerospace Research Institute of Materials and Processing Technology Beijing 100076China

The micros tructural evolution and mechanical properties of a new Al-3.8 Cu-1.2 Li-0.4 Mg-0.4 Zn-0.4 Ag-0.3 Mn-X alloy treated at different solution temperatures were *** grain size was measured in optical micrograph(OM).The residual particles and the major precipitates were identified by electron probe microanalysis(EPMA),scanning electron microscopy(SEM) and transmission electron microscope(TEM),*** results show that the peak strength appears at 530℃/1 h+T6(165℃/20 h) and the values are 566.2 MPa(tensile strength) and 538.2 MPa(yield strength) with the elongation of 6.5 %.The strength of the alloy increases rapidly with the amount of the precipitates T1 and θ’ increasing when the solution temperature is530℃.The increase in density of precipitates is resulted from the residual particles Al2 Cu,and particles enriched with Cu,Mg,Zr and Ag dissolve into matrix gradually with the solution temperature ***,the number of precipitates decreases and part of the grain boundary weakens with a further increase in solution temperature from 540 to 550℃,leading to a decline of strength.

关键词： Solution treatment Precipitates Microstructure Al-Cu-Li alloys

Resistance of Cement-based Grouting Materials with Nano- SiO_(2) Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 114-119页

作者： LI Shuiping cheng Jian WEI Chao yuAN Bin yu chengxiao College of Architectural Science and Engineering Yangzhou UniversityYangzhou 225127China

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction(XRD)and scanning electron microscopy(SEM)of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO_(2) emulsion significantly decreased the compressive strength loss and calcium hydroxide(CH)crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO_(2) particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

关键词： grouting materials nano-SiO_(2)emulsion chloride ion penetration,weight loss strength loss

The preparation and anti-angiogenic activity of polysaccharides from Karenia mikimotoi

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The preparation and anti-angiogenic activity of polysacchari...

Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

中国化学会第十届全国天然有机化学学术会议

作者： cheng-yu tan Liang Kong Shi-Jiao Zha Xiao-Hui Chi Bin Liu Marine Environmental Engineering College Dalian Ocean University

Karenia mikimotoi is a kind of bloom microalgae which can often result in serious ocean harm in the *** studies focused on its toxin from *** and its *** article was on the preparation of the polysaccharides from *** and their anti-angiogenic *** preparation process was assessed by comparing different extraction such as soxhlet’s extraction,

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： Jie Bai Jian Hui Jia yu Wang Chun cheng Yang Qing Jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

在线社交对消费者需求的影响研究——基于网络视频产业的实证分析

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中国软科学 2017年第6期 39-48页

作者：龚诗阳李倩余承锬对外经济贸易大学国际商学院北京100029 北京外国语大学国际商学院北京100089

本文围绕"在线社交是否会影响消费者需求"这一核心问题,从两个国内知名的视频网站上收集了2015-2016年发布的110部视频节目的客观数据,通过建立计量模型开展了一项探索性的实证研究。研究结果表明,在线社交对消费者需求具有显著的正向... 详细信息

本文围绕"在线社交是否会影响消费者需求"这一核心问题,从两个国内知名的视频网站上收集了2015-2016年发布的110部视频节目的客观数据,通过建立计量模型开展了一项探索性的实证研究。研究结果表明,在线社交对消费者需求具有显著的正向影响作用。具体而言,在线社交数量每提升1%,消费者需求将增加约0.5%。此外,我们还发现,第三方评论网站的节目评分对在线社交的影响效果具有负向调节作用:对于评分较低的视频节目,在线社交对消费者需求的影响较大;而对于评分较高的节目,在线社交对消费者需求的影响效果则有所下降。最后,本文基于研究结论对相关企业和行业的发展提供了管理建议。

关键词：在线社交收视行为网络视频用户生成内容实证研究

Actively tunable electromagnetically induced transparency in hybrid Dirac-VO2 metamaterials

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Optoelectronics Letters 2025年第1期21卷 13-20页

作者： DI Ke XIE Meng XIA Huarong cheng Anyu LIU yu DU Jiajia Department of Optoelectronic Engineering Chongqing University of Post and Telecommunications Chongqing Key Laboratory of Autonomous Navigation and Microsystem Chongqing University of Posts and Telecommunications Department of Automation Chongqing University of Post and Telecommunications

In this paper, we present a metamaterial structure of Dirac and vanadium dioxide（VO2） and investigate its optical properties using the finite-difference time-domain（FDTD） technique. Using the phase transition feature of VO2, the design can realize active tuning of the plasmon induced transparency（PIT） effect at terahertz frequency, thereby converting from a single PIT to a double-PIT. When VO2is in the insulating state, the structure is symmetric to obtain a single-band PIT effect. When VO2is in the metallic state, the structure turns asymmetric to realize a dual-band PIT effect. This design provides a reference direction for the design of actively tunable metamaterials. Additionally, it is discovered that the transparent window's resonant frequency and the Fermi level in this structure have a somewhat linear relationship. In addition, the structure achieves superior refractive index sensitivity in the terahertz band, surpassing 1 THz/RIU. Consequently, the design exhibits encouraging potential for application in refractive index sensors and optical switches.

关键词： Transparency

Relationship between longitudinal changes in lipid composition and ischemic stroke among hypertensive patients

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World Journal of Clinical Cases 2025年第4期13卷 18-27页

作者： cheng-cheng Wei yu-Qing Huang cheng-Hong yu Department of Cardiology Tongxiang First People's HospitalTongxiang 314500Zhejiang ProvinceChina Department of Cardiology Guangdong Cardiovascular InstituteGuangzhou 510080Guangdong ProvinceChina

BACKGROUND Dyslipidemia was strongly linked to stroke,however the relationship between dyslipidemia and its components and ischemic stroke remained *** To investigate the link between longitudinal changes in lipid profiles and dyslipidemia and ischemic stroke in a hypertensive *** Between 2013 and 2014,6094 hypertension individuals were included in this,and ischemic stroke cases were documented to the end of *** changes of lipid were stratified into four groups:(1)Normal was transformed into normal group;(2)Abnormal was transformed into normal group;(3)Normal was transformed into abnormal group;and(4)Abnormal was transformed into abnormal *** examine the link between longitudinal changes in dyslipidemia along with its components and the risk of ischemic stroke,we utilized multivariate Cox proportional hazards models with hazard ratio(HR)and 95%*** The average age of the participants was 62.32 years±13.00 years,with 329 women making up 54.0%of the *** the course of a mean follow-up of 4.8 years,143 ischemic strokes *** normal was transformed into normal group was used as a reference,after full adjustments,the HR for dyslipidemia and ischemic stroke among abnormal was transformed into normal group,normal was transformed into abnormal group and abnormal was transformed into abnormal Wei CC et *** changed and ischemic stroke WJCC https://*** 2 February 6,2025 Volume 13 Issue 4 group were 1.089(95%CI:0.598-1.982;P=0.779),2.369(95%CI:1.424-3.941;P<0.001)and 1.448(95%CI:1.002-2.298;P=0.047)(P for trend was 0.233),*** In individuals with hypertension,longitudinal shifts from normal to abnormal in dyslipidemia-particularly in total and low-density lipoprotein cholesterol-were significantly associated with the risk of ischemic stroke.

关键词： Longitudinal change Hypertension Dyslipidemia Lipid profile Ischemic stroke

Gradient‑Layered MXene/Hollow Lignin Nanospheres Architecture Design for Flexible and Stretchable Supercapacitors

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Nano-Micro Letters 2025年第2期17卷 447-462页

作者： Haonan Zhang cheng Hao Tongtong Fu Dian yu Jane Howe Kaiwen Chen Ning Yan Hao Ren Huamin Zhai Jiangsu Provincial Key Lab of Sustainable Pulp and Paper Technology and Biomass Materials NanJing Forestry UniversityNanjing 210037People’s Republic of China Department of Chemical Engineering and Applied Chemistry University of Toronto200 College StreetTorontoON M5S 3E5Canada Department of Materials Science and Engineering University of Toronto184 College StreetTorontoON M5S 3E4Canada College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037People’s Republic of China

With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has *** this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable *** depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene ***,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of *** these strategies effectively enhanced the capacitive performance of the *** addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the *** electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),***,their capacitances were well preserved after 1000 times of 600%stretch-release *** study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.

关键词： Hollow lignin nanospheres MXene Gradient-layered architecture Wrinkled electrodes Stretchable supercapacitors

Wideband high gain millimeter wave antenna based on wavy power divider for millimeter wave radar sensor

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The Journal of China Universities of Posts and Telecommunications 2025年

作者： Zhang Shuanggen yu Tao Wang yulan Zhou Ran cheng Zhihua School of Integrated Circuit Science and Engineering， Tianjin University of Technology

In this paper， a broadband high gain millimeter wave radar array antenna based on a wavy power divider is proposed. The radar antenna comprises a wavy power divider and a 10-element array antenna. By adjusting the wavy radius of the power divider， the surface current of the power divider is altered， resulting in better impedance matching with the antenna. This ultimately leads to a significant improvement in bandwidth performance. The 410 millimeter wave radar antenna loaded with wavy power divider exhibits an approximate enhancement of 3 GHz compared to traditional microstrip power divider antennas， and an average gain increase of 2.42 dB within the vehicle millimeter wave radar frequency band relative to the improved gradient power divider structure. The 410 millimeter wave radar antenna loaded with wavy power divider possesses the characteristics of high gain and broad bandwidth.

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