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Journal of Advanced Ceramics 2024年第3期13卷 263-271页

作者： xuanyu Chen Ziqi Ma Bin li Yejing Dai School of Materials Sun Yat-sen UniversityShenzhen 518107China

In this study,(Cr_(1/3)/Ta_(2/3))non-equivalent co-doped Bi_(4)Ti_(3)O_(12)(BIT)ceramics were prepared to solve the problem that high piezoelectric performance,high Curie temperature,and high-temperature resistivity could not be achieved simultaneously in BIT-based ceramics.A series of Bi_(4)Ti_(3-x)(Cr_(1/3)Ta_(2/3))_(x)O_(12)(x=0-0.04)ceramics were synthesized by the solid-state reaction method.The phase structure,microstructure,piezoelectric performance,and conductive mechanism of the samples were systematically investigated.The B-site non-equivalent co-doping strategy combining high-valence Ta^(5+)and low-valence Cr^(3+)significantly enhances electrical properties due to a decrease in oxygen vacancy concentration.Bi_(4)Ti_(2.97)(Cr_(1/3)Ta_(2/3))_(0.03)O_(12)ceramics exhibit a high piezoelectric coefficient(d_(33)=26 pC·N^(-1))and a high Curie temperature(TC=687℃).Moreover,the significantly increased resistivity(ρ=2.8×10^(6)Ω·cm at 500℃)and good piezoelectric stability up to 600℃are also obtained for this composition.All the results demonstrate that Cr/Ta co-doped BIT-based ceramics have great potential to be applied in high-temperature piezoelectric applications.

关键词： high temperature piezoelectricity co-doped Bi_(4)Ti_(3)O_(12)(BIT)

Proton‑Prompted ligand Exchange to Achieve High‑Efficiency CsPbI_(3) Quantum Dot light‑Emitting Diodes

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Nano-Micro Letters 2024年第6期16卷 53-62页

作者： Yanming li Ming Deng xuanyu Zhang Lei Qian Chaoyu Xiang Laboratory of Advanced Nano‑Optoelectronic Materials and Devices Qianwan Institute of CNITECHNingbo 315300People’s Republic of China Division of Functional Materials and Nanodevices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Faculty of Electrical Engineering and Computer Science Ningbo UniversityNingbo 315211ZhejiangPeople’s Republic of China University of Nottingham Ningbo China Ningbo 315100People’s Republic of China

CsPbI_(3)perovskite quantum dots(QDs)are ideal materials for the next generation of red light-emitting diodes.However,the low phase stability of CsPbI_(3)QDs and long-chain insulating capping ligands hinder the improvement of device performance.Traditional in-situ ligand replacement and ligand exchange after synthesis were often difficult to control.Here,we proposed a new ligand exchange strategy using a proton-prompted insitu exchange of short 5-aminopentanoic acid ligands with long-chain oleic acid and oleylamine ligands to obtain stable small-size CsPbI_(3)QDs.This exchange strategy maintained the size and morphology of CsPbI_(3)QDs and improved the optical properties and the conductivity of CsPbI_(3)QDs films.As a result,high-efficiency red QD-based light-emitting diodes with an emission wavelength of 645 nm demonstrated a record maximum external quantum efficiency of 24.45%and an operational half-life of 10.79 h.

关键词： CsPbI_(3) perovskite quantum dots light-emitting diodes ligand exchange Proton-prompted in-situ exchange

Mn-based cathode materials for rechargeable batteries

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Science China Chemistry 2024年第1期67卷 87-105页

作者： Xu Zhang Shiqi liu Boya Wang Guoqing Wang Haozhe Du xuanyu Wang Haidong Zhang Shu Zhao lin Wang Haijun Yu Institute of Advanced Battery Materials and Devices Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Key Laboratory of Advanced Functional Materials Ministry of EducationBeijing University of TechnologyBeijing 100124China Create Energy&Benefit Future Co.Ltd. Beijing 100176China

The rapid expansion of renewable energies asks for great progress of energy-storage technologies for sustainable energy supplies,which raises the compelling demand of high-performance rechargeable batteries.To satisfy the huge demand from the coming energy-storage market,the resource and cost-effectiveness of rechargeable batteries become more and more important.Manganese(Mn)as a key transition element with advantages including high abundance,low cost,and low toxicity derives various kinds(spinels,layered oxides,polyanions,Prussian blue analogs,etc.)of high-performance Mn-based electrode materials,especially cathodes,for rechargeable batteries ranging from li-ion batteries,Na-ion batteries,aqueous batteries,to multivalent metal-ion batteries.It is anticipated that Mn-based materials with Mn as the major transition-metal element will constitute a flourishing family of Mn-based rechargeable batteries(Mn RBs)for large-scale and differentiated energy-storage applications.On the other hand,several critical issues including Jahn-Teller effect,Mn dissolution,and O release greatly hinder the pace of Mn RBs,which require extensive material optimizations and battery/system improvements.This review aims to provide an investigation about Mn-based materials and batteries for the coming energy-storage demands,with compelling issues and challenges that must be overcome.

关键词： manganese cathode materials Mn-based rechargeable batteries energy storage

全民所有自然资源资产损害民事救济的实现路径

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南京工业大学学报（社会科学版） 2024年第1期23卷 69-81,114页

作者：李挚萍秦萱钰中山大学法学院广东广州510275

国家作为全民所有自然资源资产所有权人的损害赔偿请求权在司法实践中长期处于休眠状态,传统的财产侵权损害赔偿与生态环境损害赔偿均难以实现对全民所有自然资源资产所有权损害的全面救济。全民所有自然资源资产所有权相较于民法上的... 详细信息

国家作为全民所有自然资源资产所有权人的损害赔偿请求权在司法实践中长期处于休眠状态,传统的财产侵权损害赔偿与生态环境损害赔偿均难以实现对全民所有自然资源资产所有权损害的全面救济。全民所有自然资源资产所有权相较于民法上的传统所有权而言具有诸多特殊性,应将全民所有自然资源资产损害的救济定位为一种特殊的私权救济,在特殊所有权视阈下对损害赔偿进行适度的公益性扩张。以全民所有权作为全民所有自然资源资产损害救济的权利基础,探索全民所有自然资源资产所有权损害救济之上附带生态环境公共利益救济的可能性,规范全民所有自然资源资产损害赔偿的救济类型,明确索赔主体,厘清损害赔偿范围,完善公益性的救济程序并妥善处理好其与关联诉讼的关系。

关键词：全民所有自然资源资产特殊私权附带生态价值生态损害赔偿环境公共利益

Enhancing gene editing efficiency for cells by CRISPR/Cas9 system-loaded multilayered nanoparticles assembled via microfluidics

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Chinese Journal of Chemical Engineering 2021年第10期34卷 216-220页

作者： xuanyu li Qiang Feng Ziwei Han Xingyu Jiang Shenzhen Bay Laboratory Department of Biomedical EngineeringSouthern University of Science and TechnologyShenzhen 518055China

Most non-viral carriers for in vitro delivery of nucleic acids suffer from low efficiency of introducing m RNA and other nucleic acids,especially large m RNA.Cas9 protein is the nuclease part of the powerful gene-editing tool,CRISPR/Cas9 system,Cas9 m RNA is particularly large,thus presents a big challenge for delivery.We assembled a multilayered biodegradable nanocarrier to load Cas9 m RNA inside to protect Cas9 m RNA from degradation.We used a microfluidic chip to synthesize a small,positively charged,and degradable core to attract negatively charged Cas9 m RNA.The microfluidic assembly allows the core to be small enough to incorporate into a cationic liposome.The multilayered nanocarriers elevated the delivery efficiency of Cas9 m RNA by over 2 folds and increased the expression by over 5 folds compared to commercially used non-viral carriers.In addition,the multilayered nanocarriers do not require reduced serum medium for transfection.When using the standard complete medium for transfection,the multilayered nanocarriers could increase the expression of Cas9 m RNA by over 15 folds compared to commercially used non-viral carriers.The co-delivery of Cas9 m RNA and sg RNA via LRC elevated the gene-editing efficiency by 3 folds compared to that via commercially used non-viral carriers.Based on the higher transfection efficiency of Cas9 m RNA/sg RNA than commercially used non-viral carriers,these multilayered nanocarriers may have a good prospect as efficient commercial delivery carriers for Cas9 m RNA/sg RNA and other nucleic acids.

关键词： Nanotechnology Biomedical engineering Microfluidics CRISPR/Cas9 system Poly(lactic-co-glycolic acid)

多尺度混杂纤维增强珊瑚混凝土的单轴压缩性能

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硅酸盐学报 2024年第5期52卷 1543-1553页

作者：刘兵李元举王洋明阳张轩煜钱凯桂林理工大学广西绿色建材与建筑工业化重点实验室桂林理工大学土木与建筑工程学院中南大学土木工程学院

珊瑚混凝土是进行岛礁开发建设的重要建筑材料之一，多尺度混杂纤维掺入可从多尺度改善珊瑚混凝土的受力性能，从而拓展其应用范围。以碳纤维（CFs）和玄武岩纤维（BFs）作为微丝纤维、以塑钢纤维（PSFs）作为粗纤维制备了混杂纤维增强... 详细信息

珊瑚混凝土是进行岛礁开发建设的重要建筑材料之一，多尺度混杂纤维掺入可从多尺度改善珊瑚混凝土的受力性能，从而拓展其应用范围。以碳纤维（CFs）和玄武岩纤维（BFs）作为微丝纤维、以塑钢纤维（PSFs）作为粗纤维制备了混杂纤维增强珊瑚混凝土（HFRCC），通过单轴压缩试验研究了其受力性能。结果表明：HFRCC的单轴受压全过程可分为线弹性、裂缝稳定发展、裂缝不稳定发展和峰后破坏4个阶段，微丝纤维主要在峰前裂缝发展阶段发挥作用，而粗纤维主要在峰后阶段发挥作用。综合考虑强度和韧性指标，当CFs、BFs体积掺量分别为0.15%,PSFs掺量为7 kg/m3时，HFRCC表现出更优异的性能；与基准组相比，峰值应力、峰值应变和峰后压缩韧性分别提高了6.22%、38.54%和116.44%。基于CEB-FIP和过镇海的本构模型建立了适用于HFRCC的修正本构模型，模型计算曲线与实测曲线吻合较好。通过修正本构模型探讨了HFRCC的损伤演化过程，发现CFs、BFs和PSFs混杂掺入可以协同延缓珊瑚混凝土的损伤进程。

关键词：本构模型压缩韧性协同效应损伤演化珊瑚混凝土混杂纤维

Neuronal reprogramming in treating spinal cord injury

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Neural Regeneration Research 2022年第7期17卷 1440-1445页

作者： xuanyu Chen Hedong li Department of Neuroscience&Regenerative Medicine Medical College of Georgia at Augusta UniversityAugustaGAUSA

Spinal cord injury represents a devastating central nervous system injury that could impair the mobility and sensory function of afflicted patients.The hallmarks of spinal cord injury include neuroinflammation,axonal degeneration,neuronal loss,and reactive gliosis.Furthermore,the formation of a glial scar at the injury site elicits an inhibitory environment for potential neuroregeneration.Besides axonal regeneration,a significant challenge in treating spinal cord injury is to replenish the neurons lost during the pathological process.However,despite decades of research efforts,current strategies including stem cell transplantation have not resulted in a successful clinical therapy.Furthermore,stem cell transplantation faces serious hurdles such as immunorejection of the transplanted cells and ethical issues.In vivo neuronal reprogramming is a recently developed technology and leading a major breakthrough in regenerative medicine.This innovative technology converts endogenous glial cells into functional neurons for injury repair in the central nervous system.The feasibility of in vivo neuronal reprogramming has been demonstrated successfully in models of different neurological disorders including spinal cord injury by numerous laboratories.Several reprogramming factors,mainly the pro-neural transcription factors,have been utilized to reprogram endogenous glial cells into functional neurons with distinct phenotypes.So far,the literature on in vivo neuronal reprogramming in the model of spinal cord injury is still small.In this review,we summarize a limited number of such reports and discuss several questions that we think are important for applying in vivo neuronal reprogramming in the research field of spinal cord injury as well as other central nervous system disorders.

关键词： astrocyte microRNA NeuroD1 neuronal relay neuronal reprogramming NG2 glia pericyte reactive gliosis Sox2 spinal cord injury

天山南坡阿克苏流域冰川物质平衡及其融水径流对气候变化的响应研究

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地学前缘 2024年第2期31卷 435-446页

作者：王鹏寿许民韩海东李振中宋轩宇周卫永兰州交通大学数理学院甘肃兰州730070 中国科学院西北生态环境资源研究院冰冻圈科学国家重点实验室甘肃兰州730000 中国科学院大学北京100049 兰州交通大学测绘与地理信息学院甘肃兰州730070

冰川融水是西北干旱区水资源重要组成部分,定量评估其变化对中、下游生态环境保护和工农业经济可持续发展具有重要意义。本文基于国家气象台站日降水和气温资料、数字高程模型(DEM)以及第一次冰川编目数据,利用度日模型模拟了天山南坡... 详细信息

冰川融水是西北干旱区水资源重要组成部分,定量评估其变化对中、下游生态环境保护和工农业经济可持续发展具有重要意义。本文基于国家气象台站日降水和气温资料、数字高程模型(DEM)以及第一次冰川编目数据,利用度日模型模拟了天山南坡阿克苏流域1957—2017年冰川物质平衡及其融水径流变化,分析了融水径流组成及其对气候变化的响应。结果表明:1957—2017年流域年平均物质平衡为-94.6 mm w.e.,61年累积物质平衡为-5.8 m w.e.。流域冰川物质平衡线呈显著上升趋势,年均上升速率为1.6 m/a。研究区年均融水径流量为53.1×10^(8)m^(3),融水增加速率为0.24×10^(8)m^(3)/a,融水径流及其组成分量均呈显著增加趋势。在气候暖湿化背景下,流域降水的增加使得冰川区积累量增加,在剧烈的升温作用下,冰川消融加剧,气温对融水径流的作用增大,因此冰川物质平衡亏损产生的水文效应增强。研究结果可提升区域冰川水资源效应变化及其影响的认识。

关键词：度日模型冰川物质平衡融水径流阿克苏流域气候变化

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基于模型偏差学习的交通信号自适应优化方法

铁道科学与工程学报 2024年第6期21卷 2229-2240页

作者：黄玮张轩宇李世昌赵靖中山大学智能工程学院广东深圳518107 上海理工大学智慧城市交通研究院上海200093

城市交通信号配时优化是保证交通系统整体运行效率的前提条件。传统基于模型的信号控制方法往往基于历史统计数据,并且底层交通流模型不可避免地存在模型偏差,影响控制方案的科学性及其实际应用效果。考虑模型与数据融合驱动,提出一种... 详细信息

城市交通信号配时优化是保证交通系统整体运行效率的前提条件。传统基于模型的信号控制方法往往基于历史统计数据,并且底层交通流模型不可避免地存在模型偏差,影响控制方案的科学性及其实际应用效果。考虑模型与数据融合驱动,提出一种基于模型偏差学习的交通信号控制自适应优化方法,以最小化路网行程时间为目标,建立信号控制最优化模型。首先,针对交通流预测模型的模型偏差,引入偏差函数表示预测模型与实际交通流状态间的误差;其次,建立基于径向基函数(RBF)神经网络的偏差函数,结合实际交通流数据对模型偏差进行学习,提高偏差函数的拟合效果;在此基础上,提出考虑模型偏差信息的自适应优化方法,以提高信号控制方法的控制性能。以小型测试路网与实际路网为例进行算例分析,基于SUMO仿真对本文提出的模型偏差学习方法进行验证,考虑不同交通流量条件,与固定配时、模型预测控制进行比较,分析其控制性能指标。结果表明,模型与数据融合驱动的信号控制自适应优化方法能有效提高预测模型的准确性,降低路网行程时间,与基于模型的控制和模型预测控制方法相比路网累积行程时间平均减少了38.3%和25.6%,提升了路网的实际运行效果。最后在宣城实际路网的仿真验证了方法的有效性。

关键词：城市道路交通信号控制模型与数据融合驱动模型偏差自适应优化

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基于深度神经网络的目标跟踪算法综述

航空兵器 2024年第1期31卷 1-12页

作者：郭凡卢铉宇李嘉怡王红梅西北工业大学航天学院西安710072

目标跟踪是根据视频序列中目标的前续信息,对目标的当前状态进行预测。深度学习在目标跟踪领域逐渐广泛应用,本文阐述了目标跟踪算法和深度学习的发展背景,对传统目标跟踪进行了回顾,根据不同的网络任务功能,将基于深度学习的目标跟踪... 详细信息

目标跟踪是根据视频序列中目标的前续信息,对目标的当前状态进行预测。深度学习在目标跟踪领域逐渐广泛应用,本文阐述了目标跟踪算法和深度学习的发展背景,对传统目标跟踪进行了回顾,根据不同的网络任务功能,将基于深度学习的目标跟踪算法分为:基于分类的深度学习目标跟踪算法、基于回归的深度学习目标跟踪算法、基于回归与分类结合的目标跟踪算法,并选取了具有代表性的目标跟踪算法进行实验,对比不同算法之间的特点;最后对目前基于深度学习的目标跟踪方法存在的问题进行分析,对未来发展方向进行展望。实验结果证明,深度孪生跟踪网络在精度与速度上均占优,成为当前主流的跟踪算法框架。

关键词：目标跟踪深度学习神经网络卷积神经网络孪生神经网络生成对抗网络