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Electrospun Fluorinated Polyimide/Polyvinylidene Fluoride Composite Membranes with High Thermal Stability for Lithium Ion Battery Separator

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Advanced Fiber Materials 2022年第1期4卷 108-118页

作者： Jianwei Li Xuanning Zhang Yuyan Lu Keliang Linghu Chen Wang zhonglei Ma Xinhai he School of Materials Science and Engineering Xi’an Polytechnic UniversityXi’an 710048China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemical and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China National Advanced Functional Fiber Innovation Center Suzhou 215000China

The separator with excellent mechanical and thermal properties are highly required for lithium ion batteries(LIBs).Therefore,it is crucial to develop novel nanofbrous membranes with enhanced mechanical strength and thermal stability.In this work,the fuorinated polyimide(FPI)was synthesized and blended with polyvinylidene fuoride(PVDF)to fabricate composite nanofbrous membranes(CNMs)via electrospinning method.Benefting from the introduction of aromatic FPI,the prepared PVDF/FPI nanofbrous membranes were endowed with enhanced mechanical strength and thermal stability.When the FPI content increased from 0 to 30 wt%,the tensile strength of composite nanofbrous membranes enhanced from 1.57 to 2.30 MPa.Moreover,there are almost no dimensional shrinkage for the CNM-30 containing 30 wt%FPI after heat treatment at 160℃ for 1 h.Furthermore,the prepared CNMs show improved electrochemical performances in comparison with neat PVDF and commercial Celgard membranes.The electrolyte uptake and ionic conductivity of the CNMs could reach to 522.4% and 1.14 ms·cm^(−1),respectively.The prepared CNMs could provide an innovative and promising approach for the development and design of high-performance separators.

关键词： Nanofbrous membrane PVDF Polyimide Lithium ion battery Separator

Observations and parametric study on the role of plasma density on extremely low-frequency chorus wave generation

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Science China(Technological Sciences) 2022年第11期65卷 2649-2657页

作者： he Qian LIU Si XIAO FuLiang GAO zhonglei LI Tong SHANG XiongJun ZHOU QingHua YANG Chang he YiHua School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China

Extremely low-frequency(ELF)chorus waves with frequencies below 0.1 fcecan cause the scattering losses of relativistic electrons.Previous studies have suggested that ELF chorus waves are excited by anisotropic electrons with energies up to a few hundred ke V.here,we report an interesting event observed using the Van Allen Probes on November 1,2012,where distinct ELF chorus waves occurred exactly corresponding to the enhancement of the plasma density.Using the correlated data of particles and plasma environments,the continuous calculation of growth rates along the satellite trajectory was conducted.The linear analysis results display a similar pattern to the observation results.To further identify the impact of the plasma density on the frequency control of ELF chorus waves,the growth rates were then calculated by only changing the value of the plasma density.The calculation results show that the growth rates move to lower frequencies with plasma density enhancement during the event.These findings indicate that the increased plasma density has a considerable impact on the wave frequency.The current study can enrich our understanding of the possible role of plasma density on the generation of ELF chorus waves.

关键词： radiation belts plasma density extremely low-frequency chorus waves numerical simulation

A machine-learning-based electron density (MLED) model in the inner magnetosphere

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Earth and Planetary Physics 2022年第4期6卷 350-358页

作者： QingHua Zhou YunXiang Chen FuLiang Xiao Sai Zhang Si Liu Chang Yang YiHua he zhonglei Gao School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering Changsha University of Science and TechnologyChangsha 410114China

Plasma density is an important factor in determining wave-particle interactions in the magnetosphere.We develop a machine-learning-based electron density(MLED)model in the inner magnetosphere using electron density data from Van Allen Probes between September 25,2012 and August 30,2019.This MLED model is a physics-based nonlinear network that employs fundamental physical principles to describe variations of electron density.It predicts the plasmapause location under different geomagnetic conditions,and models separately the electron densities of the plasmasphere and of the trough.We train the model using gradient descent and backpropagation algorithms,which are widely used to deal effectively with nonlinear relationships among physical quantities in space plasma environments.The model gives explicit expressions with few parameters and describes the associations of electron density with geomagnetic activity,solar cycle,and seasonal effects.Under various geomagnetic conditions,the electron densities calculated by this model agree well with empirical observations and provide a good description of plasmapause movement.This MLED model,which can be easily incorporated into previously developed radiation belt models,promises to be very helpful in modeling and improving forecasting of radiation belt electron dynamics.

关键词： background electron density inner magnetosphere machine learning Van Allen Probes observation

Direct evidence for efficient scattering of suprathermal electrons by whistler mode waves in the Martian magnetosphere

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Earth and Planetary Physics 2023年第6期7卷 607-614页

作者： Tong Li Si Liu Chang Yang FuLiang Xiao HongMing Yang Sai Zhang zhonglei Gao Qian he QingHua Zhou QiWu Yang YiHua he School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Whistler mode waves are critical emissions in magnetized plasmas that usually influence the electron dynamics in a planetary magnetosphere.In this paper,we present a unique event in the Martian magnetosphere in which enhanced whistler mode waves(~10^(−11) V^(2)/m^(2)/Hz)with frequency of 0.1 f_(ce)-0.5 f_(ce) occurred,based on MAVEN data,exactly corresponding to a significant decrease of suprathermal electron fluxes.The diffusion coefficients are calculated by using the observed electric field wave spectra.The pitch angle diffusion coefficient can approach 10^(−2) s^(−1),which is much larger,by~100 times,than the momentum diffusion coefficient,indicating that pitch angle scattering dominates the whistler-electron resonance process.The current results can successfully explain the dropout of the suprathermal electrons in this event.This study provides direct evidence for whistler-driven electron losses in the Martian magnetosphere.

关键词： whistler mode waves diffusion coefficients electron scattering Martian magnetosphere

Crosstalk between IL-15Rα^(+)tumor-associated macrophages and breast cancer cells reduces CD8+T cell recruitment

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Cancer Communications 2022年第6期42卷 536-557页

作者： Wenlong Zhang Qing Zhang Nanfei Yang Qian Shi Huifang Su Tingsheng Lin Zhonglei He Wenxin Wang Hongqian Guo Pingping Shen State Key Laboratory of Pharmaceutical Biotechnology and Department of Urology Nanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolSchool of Life SciencesNanjing UniversityNanjingJiangsu 210023P.R.China Department of Urology Drum Tower HospitalMedical School of Nanjing UniversityInstitute of UrologyNanjing UniversityNanjingJiangsu 210008P.R.China Shenzhen Research Institute of Nanjing University Shenzhen 518000China Department of Cellular and Integrative Physiology The University of Texas Health Science Center at San AntonioSan AntonioTexas 78229-3904USA Charles Institute of Dermatology School of MedicineUniversity College DublinDublin Eircode D04 V1W8Ireland

Background:Interleukin-15(IL-15)is a promising immunotherapeutic agent owing to its powerful immune-activating effects.However,the clinical benefits of these treatments are limited.Crosstalk between tumor cells and immune cells plays an important role in immune escape and immunotherapy drug resistance.herein,this study aimed to obtain in-depth understanding of crosstalk in the tumor microenvironment for providing potential therapeutic strategies to prevent tumor progression.Methods:T-cell killing assays and co-culture models were developed to determine the role of crosstalk between macrophages and tumor cells in breast cancer resistant to IL-15.Western blotting,histological analysis,CRISPR-Cas9 knockout,multi-parameter flow cytometry,and tumor cell-macrophage co-injection mouse models were developed to examine the mechanism by which IL-15Rα^(+)tumor-associated macrophages(TAMs)regulate breast cancer cell resistance to IL-15.Results:We found thatmacrophages contributed to the resistance of tumor cells to IL-15,and tumor cells induced macrophages to express high levels of theαsubunit of the IL-15 receptor(IL-15Rα).Further investigation showed that IL-15Rα^(+)TAMs reduced the protein levels of chemokine CX3C chemokine ligand 1(CX3CL1)in tumor cells to inhibit the recruitment of CD8^(+)T cells by releasing the IL-15/IL-15Rαcomplex(IL-15Rc).Administration of an IL-15Rc blocking peptide markedly suppressed breast tumor growth and overcame the resistance of cancer cells to anti-programmed cell death protein 1(PD-1)antibody immunotherapy.Interestingly,Granulocyte-macrophage colony-stimulating factor(GMCSF)inducedγchain(γc)expression to promote tumor cell-macrophage crosstalk,which facilitated tumor resistance to IL-15.Additionally,we observed that the non-transcriptional regulatory function of hypoxia inducible factor-1alpha(HIF-1α)was essential for IL-15Rc to regulateCX3CL1 expression in tumor cells.Conclusions:The IL-15Rc-HIF-1α-CX3CL1 signaling pathway serves as a crosstalk between macrophages and tumor cells in the t

关键词： breast cancer CD8^(+)T-cell crosstalk IL-15Rα immunotherapy tumor microenvironment tumor-associated macrophages

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明代万历“庄浪兵变”与鲁氏家族

高原文化研究 2023年第3期1卷 46-58页

作者：张中磊青海师范大学历史学院青海西宁810008

明代庄浪卫鲁氏家族长期受到朝廷倚重,其权势不断扩张,后逐渐成为部分明朝官员眼中的“庄浪隐忧”,大有“尾大不掉之势”。鲁东时期,鲁氏权势开始衰微,鲁东长期卧病,对土军缺乏有效管束,加之庄浪卫土、汉军士与庄浪兵备道之间关于马匹... 详细信息

明代庄浪卫鲁氏家族长期受到朝廷倚重,其权势不断扩张,后逐渐成为部分明朝官员眼中的“庄浪隐忧”,大有“尾大不掉之势”。鲁东时期,鲁氏权势开始衰微,鲁东长期卧病,对土军缺乏有效管束,加之庄浪卫土、汉军士与庄浪兵备道之间关于马匹料草的“本折之争”,致使庄浪卫发生“乙亥鼓噪”,成为石茂华等人试图削弱鲁氏的良好契机。“乙亥鼓噪”后石茂华等人提出增设防守土官、建社学、立乡约保甲等措施,意在强调明王朝在庄浪卫的“在场感”,树立“国家权威”。这些整饬措施虽然对鲁氏家族产生一定消极影响,但并未使鲁氏家族一蹶不振。在郑洛经略青海期间,鲁氏仍发挥了重要的作用,参与到招抚番族尤其是海上诸番的重要军事行动中,家族权势也一度得到重振。不过由于鲁光祖、鲁光国骄横跋扈,加之往年兵变影响,鲁氏屡次遭梁云龙、宋一韩等对其有防备之心的官员弹劾。最终在万历三十九年(1611年)鲁氏遭受沉重打击,不论是管民之权抑或管军之权均大大受挫,其权势一度跌至谷底。

关键词：明代庄浪卫兵变鲁氏家族

艾司氯胺酮对大鼠颅脑创伤后应激障碍行为的影响

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国际外科学杂志 2022年第4期49卷 256-261页

作者：张斌何平丽孙中磊焦阳济宁医学院附属医院神经外科济宁272001 济宁医学院附属医院神经外科ICU 济宁272001 枣庄矿业集团中心医院神经外科枣庄277400 南京同仁医院神经外科南京211102

目的探讨艾司氯胺酮对颅脑创伤后应激障碍(PTSD)行为的影响。方法选取36只成年雄性SD大鼠按随机数字表法分为3组,采用皮质撞击致伤法构建小鼠颅脑创伤模型,假手术组(Sham组,n=12)仅打开骨窗不行颅脑创伤打击,颅脑创伤组(TBI组,n=12)和... 详细信息

目的探讨艾司氯胺酮对颅脑创伤后应激障碍(PTSD)行为的影响。方法选取36只成年雄性SD大鼠按随机数字表法分为3组,采用皮质撞击致伤法构建小鼠颅脑创伤模型,假手术组(Sham组,n=12)仅打开骨窗不行颅脑创伤打击,颅脑创伤组(TBI组,n=12)和艾司氯胺酮处理组(TBI+ES组,n=12)行皮质打击;创伤后TBI+ES组即刻腹腔注射艾司氯胺酮(10 mg/kg,1次/2 h,共3次),TBI组和Sham组腹腔注射等容积0.9%氯化钠溶液。收集创伤后第(1、3、7、15)天进行糖水偏爱实验、第16天开始旷场实验、第17天开始高架十字迷宫实验结果,分析颅脑创伤后PTSD样行为改变,并于颅脑创伤后第18~23天开始采用Morris水迷宫实验评估各组大鼠学习记忆能力。实验结束后大鼠安乐死取脑组织,Western-blot分析脑源性神经营养因子(BDNF)和突触后致密蛋白95(PSD95)、突触素表达水平。正态分布的计量资料以均数±标准差(±s)表示,多组间比较用单因素方差分析(One-Way ANOVA),两两比较采用SNK-q检验,重复测量资料采用LSD法。结果 TBI组大鼠糖水偏爱率、移动格数、直立次数、开臂停留时间、开臂进入次数、逃避潜伏期和穿越平台位置次数[分别为(75.8±4.9)%、(30.9±4.1)格、(12.4±2.6)次、(40.3±8.5) s、(6.8±2.3)次、(30.0±4.6) s、(7.0±2.5)次]、低于Sham组[分别为(85.3±4.4)%、(40.5±5.4)格、(17.3±2.7)次、(95.8±12.4) s、(15.3±3.1)次、(18.3±7.8) s、(15.7±2.6)次],差异具有统计学意义(P<0.05);TBI+ES组糖水偏爱率、移动格数、直立次数、开臂停留时间、开臂进入次数、逃避潜伏期和穿越平台位置次数[分别为(82.9±5.5)%、(35.5±5.5)格、(15.1±2.4)次、(68.4±9.7) s、(12.1±3.2)次、(22.3±8.8) s、(12.5±4.1)次]高于TBI组,差异具有统计学意义(P<0.05)。TBI+ES组BDNF、PSD95和突触素表达水平[分别为(0.43±0.08)、(0.22±0.02)、(0.31±0.04)]高于TBI组[分别为(0.19±0.02)、(0.20±0.02)、(0.24±0.01)],差异具有统计学意义(P<0.05),且均低于Sham组[分别为(0.89±0.11)、(0.45±0.12)、(0.57±0.15)],差异具有统计学意义(P<0.05)。结论艾司氯胺酮显著减少颅脑创伤大鼠PTSD样行为,发挥神经保护作用,可能作为PTSD治疗的潜在药物。

关键词：大鼠颅脑损伤应激障碍,创伤后艾司氯胺酮行为学评分

日侧外磁层ULF波调制EMIC波的MMS观测

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空间科学学报 2022年第2期42卷 206-215页

作者：廖泽冬刘斯高中磊何茜李彤商雄军长沙理工大学物理与电子科学学院长沙410114 湖南省普通高校重点实验室近地空间电磁环境监测与建模实验室长沙410114

磁层多尺度卫星(MMS-1)在日侧06:30 MLT(磁地方时,Magnetic Local Time)外磁层大于2Re(L为7.5~10.1)的范围内观测到多达21个波包的准周期性电磁离子回旋波(EMIC)事件。超低频(ULF)波和能量质子温度各向异性准周期性增强也被同步观测到... 详细信息

磁层多尺度卫星(MMS-1)在日侧06:30 MLT(磁地方时,Magnetic Local Time)外磁层大于2Re(L为7.5~10.1)的范围内观测到多达21个波包的准周期性电磁离子回旋波(EMIC)事件。超低频(ULF)波和能量质子温度各向异性准周期性增强也被同步观测到。频率分析显示,ULF波的周期、质子各向异性周期和EMIC波包的周期非常接近。MMS-4卫星在约1 h后经过附近空间区域,研究发现随着ULF波的幅度减弱,EMIC波包的准周期性也逐渐减弱。研究结果为ULF波在日侧外磁层调制质子各向异性从而产生周期性EMIC波包提供了完整的观测证据链。同时,观测结果进一步证明,这种ULF波调制的EMIC波包能够在大于2Re的空间尺度内发生,且能够持续存在于几个小时以上的时间尺度。

关键词：周期性EMIC 波 ULF 波温度各向异性 MMS 任务

计算机视觉技术在玉米品种识别中的应用(英文)

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农业科学与技术：英文版 2013年第5期14卷 783-786,796页

作者：孙钟雷李宇何伟长江师范学院生命科学与技术学院重庆408100 涪陵同心利玉米专业合作社重庆408100

玉米品种的识别对玉米的育种、加工、贸易等具有重要的意义。计算机视觉技术已广泛应用于玉米品种识别中,从玉米图像获取、玉米图像处理、特征参数提取、模式识别算法、编程软件等几方面技术进行了综述,并对计算机视觉技术在玉米品种识... 详细信息

玉米品种的识别对玉米的育种、加工、贸易等具有重要的意义。计算机视觉技术已广泛应用于玉米品种识别中,从玉米图像获取、玉米图像处理、特征参数提取、模式识别算法、编程软件等几方面技术进行了综述,并对计算机视觉技术在玉米品种识别中存在的问题及发展的趋势进行了分析和展望。

关键词：玉米品种识别计算机视觉图像处理特征提取模式识别