摘要：可被蓝光激发的高热稳定性红色荧光粉是制作高性能白光二极管(WLED)的关键材料.研究发现,Ce^(3+)掺杂的SrLaScO_(4)(SLO:Ce^(3+))荧光粉在440 nm激发下呈现峰值为640 nm的反常宽带红光发射.光谱学和结构分析证实Ce^(3+)离子在SLO中进入[LaO_(8)]多面体,产生强的晶体场劈裂和较大的Stokes位移,实现了比Eu^(2+)更低能量的红光发射.我们还设计并揭示了一种电荷转移相互作用的策略:在Sc^(3+)位置引入电负性较大的Ga^(3+),Ga^(3+)可以吸引更多邻位配合基团的电荷,以减少导带底部的电子占用而扩大带隙.Sc/Ga取代有效地抑制了热激活电离过程,使SrLa(Sc,Ga)O_(4):Ce^(3+)的热稳定性获得了显著提升,即在150℃的发光强度比(相对于20℃)从15%提升至31%.本研究为发现具有良好热稳定性的新型Ce^(3+)掺杂红色荧光粉提供了有效的设计原则.

摘要：通常热力发电厂将飞灰中未燃碳的含量作为评价锅炉燃烧效率的重要指标,通过测量飞灰中未燃碳的含量来评价煤粉燃烧的充分程度,进而实现优化燃烧、提高机组效率。基于激光诱导击穿光谱技术(LIBS)无接触、快速响应、高灵敏度、可以在线测量等特点,备用来测量飞灰中未燃碳的含量。由于烟气中CO_2气体的存在,碳谱线强度会随CO_2浓度的变化而改变。为了减少CO_2气体对飞灰未燃碳测量结果的影响,提出并设计了具有二级旋风分离器的LIBS测量飞灰未燃碳含量实验系统,飞灰从给粉机流出后通过二级旋风分离器进入测量腔体,脉冲激光经过透镜作用于飞灰样品进而产生等离子体。LIBS系统采用双中心波长光谱仪,可测得飞灰中C,Si,Mg,Fe,Ca和Al等主要元素谱线,同时高分辨率通道可分辨出相邻C和Fe的元素谱线,可以在获得充分的飞灰光谱信息的同时保证了测量的精度。实验结果表明该系统可有效分离和收集飞灰颗粒,减少CO_2气体对测量结果的干扰,为LIBS技术的工程应用提供了更准确的依据。

摘要：针对视频序列中表情强度不一致,长短时记忆网络(LSTM)难以有效地提取其特征的问题,提出一种基于面部运动单元和时序注意力的视频表情识别方法.首先在卷积LSTM(ConvLSTM)的基础上引入时序注意力模块,对视频序列进行时序建模,在降低维度的同时保留丰富人脸图像特征信息;其次提出基于面部动作单元的人脸图像分割规则,解决面部表情活跃区域难以界定的问题;最后在模型中嵌入标签修正模块,解决自然条件下数据集中样本不确定性的问题.在MMI,Oulu-CASIA和AFEW数据集上的实验结果表明,所提方法的模型参数量低于已公开的主流模型,且在MMI数据集上的平均识别准确率达到87.22%,高于目前主流方法,在整体效果上优于目前具有代表性的方法.

摘要：Coupled with anionic and cationic redox chemistry,Li-rich/excess cathode materials are prospective high-energy-density candidates for the next-generation Li-ion ***,irreversible lattice oxygen loss would exacerbate irreversible transition metal migration,resulting in a drastic voltage decay and capacity ***,a metastable layered Li-excess cathode material,T2-type Li_(0.72)[Li_(0.12)Ni_(0.36)Mn_(0.52)]O_(2),was developed,in which both oxygen stacking arrangement and Li coordination environment fundamentally differ from that in conventional O3-type layered *** means of the reversible Li migration processes and structural evolutions,not only can voltage decay be effectively restrained,but also excellent capacity retention can be achieved upon long-term ***,irreversible/reversible anionic/cationic redox activities have been well assigned and quantified by various in/ex-situ spectroscopic techniques,further clarifying the charge compensation mechanism associated with(de)*** findings of the novel T2 structure with the enhanced anionic redox stability will provide a new scope for the development of high-energy-density Li-rich cathode materials.

摘要：忆阻器阵列能够有效地加速神经网络中的矩阵运算,但会受到老化的影响,导致忆阻器阵列计算精度不满足要求.为了继续使用忆阻器阵列,提出一种基于重编程忆阻单元数量约束的闭环重映射算法.首先根据忆阻器阵列的老化分布得出行偏差矩阵;然后以行偏差矩阵中的最小值为起始点开始映射,直至重映射关系形成闭环;通过在映射过程中设置行偏差约束,使得重映射后的行偏差总和尽可能小,达到提高计算精度的目的;通过对重编程单元数量进行约束,尽可能减少需要重新编程的忆阻单元数量,减轻重编程造成的忆阻器阵列老化.在Pytorch上采用MINST数据集进行仿真测试的实验结果表明,所提算法不仅能够有效地提高忆阻器阵列的计算精度,而且与国际上同类方法相比,在达到相同计算精度的前提下,最多可以减少75.43%的重编程单元数.

摘要：聚合物基固态电解质得益于其易加工性,最有希望应用于下一代固态锂金属电池.目前,聚合物基态电解质的离子电导率提升策略多为加入导锂陶瓷以构建离子传输通道,其提升程度有限.电场在锂离子输运过程中存在重要影响,目前研究中有关电场对锂离子传输的影响机制尚不明确.本文将兼具高离子电导率和高介电常数的铌酸锂嵌入聚偏氟乙烯基体中,设计了一种新型复合固态电解质.铌酸锂颗粒有效调节电解质内部电场结构,增强了离子输运方向电场强度,实现了离子电导率的大幅提升(7.39×10^(-4)S cm^(-1),25℃).该电解质匹配高镍正极和锂金属负极的固态电池可稳定循环1000次以上,容量保持率为72%.该研究为设计下一代固态锂电池用高离子电导复合固态电解质提供了新的策略.

摘要：The global increase in the prevalence of drug-resistant bacteria has necessitated the development of alternative treatments that do not rely on conventional antimicrobial *** bacteriophage-derived lytic enzymes in antibacterial therapy shows promise;however,a thorough comparison and evaluation of their bactericidal efficacy are *** study aimed to compare and investigate the bactericidal activity and spectrum of such lytic enzymes,with the goal of harnessing them for antibacterial ***,we examined the bactericidal activity of spanins,endolysins,and holins derived from 2 Escherichia coli model phages,T1 and *** these,T1-spanin exhibited the highest bactericidal activity against ***,we expressed T1-spanin within bacterial cells and assessed its bactericidal activity.T1-spanin showed potent bactericidal activity against all clinical isolates tested,including bacterial strains of 111 ***,2 Acinetobacter spp.,3 Klebsiella spp.,and 3 Pseudomonas *** contrast,T1 phage-derived endolysin showed bactericidal activity against *** and ***,yet its efficacy against other bacteria was inferior to that of ***,we developed a phage-based technology to introduce the T1-spanin gene into target *** synthesized non-proliferative phage exhibited strong antibacterial activity against the targeted *** potent bactericidal activity exhibited by spanins,combined with the novel phage synthetic technology,holds promise for the development of innovative antimicrobial agents.

摘要：As an important energy carrier in terms of carbon neutrality,green hydrogen produced by water electrolysis using renewable electricity has attracted worldwide *** polymer electrolyte water electrolyzer(PEWE)has the potential to be a mainstay in the green hydrogen market in the future because of its superior ***,the development of PEWE is constrained by the slow progress of the membrane electrode assembly(MEA),which is an essential component of PEWE and largely determines the cost and performance of the ***,the MEA must be optimized from the aspects of reducing cost and improving performance to promote the development of *** this review,we first discuss the recent progress of the materials and design strategies of MEA,including the cost,activity,and stability of catalysts,distribution and thickness of ionomers,and ion transport efficiency of ion exchange membranes(IEMs).Then,the effects of all components and interlayer interfaces on the ions,electrons,and mass transfer in MEA and,consequently,the performance of PEWE are ***,we propose perspectives on developing MEA by optimizing the catalyst activity and stability of IEM,interface contact between adjacent components,and evaluation methods of performance.

摘要：Ceramic electrolytes are important in ceramic-liquid hybrid electrolytes(CLHEs),which can effectively solve the interfacial issues between the electrolyte and electrodes in solid-state batteries and provide a highly efficient Li-ion transfer for solid–liquid Li metal *** the ionic transport mechanisms in CLHEs and the corresponding role of ceramic electrolytes is crucial for a rational design ***,the Li-ion transfer in the ceramic electrolytes of CLHEs was confirmed by tracking the 6Li and 7Li substitution behavior through solid-state nuclear magnetic resonance *** ceramic and liquid electrolytes simultaneously participate in Li-ion transport to achieve highly efficient Li-ion transfer in CLHEs.A spontaneous Li-ion exchange was also observed between ceramic and liquid electrolytes,which serves as a bridge that connects the ceramic and liquid electrolytes,thereby greatly strengthening the continuity of Li-ion pathways in CLHEs and improving the kinetics of Li-ion *** importance of an abundant solid–liquid interface for CLHEs was further verified by the enhanced electrochemical performance in LiFePO4/Li and LiNi0.8Co0.1Mn0.1O2/Li batteries from the generated *** work provides a clear understanding of the Li-ion transport pathway in CLHEs that serves as a basis to build a universal Li-ion transport model of CLHEs.

摘要：设计了一个新的表面张力测定装置,通过实时测定液膜气泡的半径及其内外压差来获得被测液体的表面张力.该测定液体表面张力的方法简称为真球气泡法(real sphere bubble method,RSBM).对十二烷基硫酸钠(sodium dodecyl sulfate,SDS)溶液的表面张力进行了测定,结果与文献值吻合,且测定装置的绝对精度为98.2%.通过检测到的液膜气泡突然长大所需要的最大压差值△Pm及其表面积随时间的变化过程,定量分析了△Pm与溶液起泡难易程度及气泡大小的关系.