Ultrafine Titanium Nitride Sheath Decorated Carbon Nanofiber Network Enabling Stable Lithium Metal Anodes

Nonuniform local electric field and few nucleation sites on the reactive interface tend to cause detrimental lithium (Li) dendrites, which incur severe safety hazards and hamper the practical application of Li metal anodes in batteries. Herein, a carbon nanofiber (CNF) mat decorated with ultrafine titanium nitride (TiN) nanoparticles (CNF‐TiN) as both current collector and host material is reported for Li metal anodes. Uniform Li deposition is achieved by a synergetic effect of lithiophilic TiN and 3D CNF configuration with a highly conductive network. Theoretical calculations reveal that Li prefers to be adsorbed onto the TiN sheath with a low diffusion energy barrier, leading to controllable nucleation sites and dendrite‐free Li deposits. Moreover, the pseudocapacitive behavior of TiN identified through kinetics analysis is favorable for ultrafast Li⁺ storage and the charge transfer process, especially under a high plating/stripping rate. The CNF‐TiN‐modified Li anodes deliver lower nucleation overpotential for Li plating and superior electrochemical performance under a large current density (200 cycles at 3 mA cm^?2) and high capacity (100 cycles with 6 mAh cm^?2), as well as a long‐running lifespan (>600 h). The CNF‐TiN‐based full cells using lithium iron phosphate and sulfur cathodes exhibit excellent cycling stability.     

PB-BBD响应面法优化全金属水力振荡器性能的研究

目前从各类水力振荡器的现场应用看,普遍存在压耗偏大的问题,使钻井液辅助破岩的能力降低。基于自激涡流振荡的原理,设计了一种全金属水力振荡器,为充分发挥其性能,降低压耗,需对振荡器内部结构进行优化。通过Plackett-Burman设计对内部各结构参数进行了筛选试验,确定显著影响参数为射流道宽度、工具厚度和出口直径,再用Box-Behnken Design响应面法对显著影响参数进行分析,得到全金属水力振荡器内部结构参数的优化组合为射流道宽度14 mm、工具厚度41.432 mm、出口直径为46 mm,最后通过数值分析验证了优化方法的有效性。     

一种先进的电网谐波检测方法

在传统的自适应检测方法的基础上,提出了一种新型的电网谐波检测方法,此法克服其他方法的局限性,不仅能够检测电压谐波,而且能够有效地检测电压的不对称等其他畸变量。仿真和试验结果表明了本文所述方法的有效性,可满足电力系统对电压畸变量检测的要求。同时,这种方法对于谐波电流检测也同样适用。     

Experimental study of a model digital space optical communication system with new quantum devices

We report a digital space optical communication system with new features both in the transmitting and in the receiving ends. The diode laser source is stabilized to within ±100 kHz by locking its frequency to the transmission peak of a Faraday anomalous dispersion optical filter (FADOF). The optical filter in the receiver uses two FADOF's that are linked to eliminate the multipeak structure and achieve a single-peak bandwidth of ~1 GHz. The detection sensitivity of this system is 23 times higher than that of a system with a traditional interference filter.     

基于改进智能水滴算法的多用户OFDMA系统资源分配

在正交频分多址(OFDMA)系统中,合理的资源分配对于提升系统的性能具有重要的意义.针对多用户OFDMA系统,对最大化系统容量为目标的资源分配算法进行研究,提出了一种基于智能水滴算法的无向全连通图资源分配模型,以无向全连通图的顶点集和边集来描述用户与子载波之间的匹配关系.在此基础上,进一步对智能水滴算法进行改进.仿真结果表明,在满足用户比例公平性的条件下,与蚁群算法相比,基于改进智能水滴算法的全连通图分配方案能够提高2.17%~4.91%的系统速率,同时具有更快的收敛速度,提高了系统性能.     

基于系统思维的海绵城市设计方法探索与实践

为缓解传统城市开发模式引发的逢雨必涝和当前海绵城市方案设计水平不高引起建设效益不佳的问题,论文以江苏某住宅小区海绵化建设方案为例,以因地制宜、统筹协调、先绿后灰、集中分散结合、雨水资源化为设计原则,提出了建筑小区海绵城市应用思路和方法.基于地块建设条件分析,文中目标与问题导向相结合,创新性地从海绵分区划分、技术选择、设施布局、竖向设计及径流组织,系统阐述了海绵城市方案设计全流程,并借助PCSWMM雨水径流模型,采用地区多年日降雨量数据,进行年径流总量控制率的目标可达性验证.结果表明,该思路和方法设计的海绵方案,能够满足地块规划指标要求,可以为住宅小区类海绵城市建设方案设计提供借鉴和参考.     

河道再生水入渗的水岩相互作用机理研究

依托引温济潮工程受水区,通过室内淋溶试验,研究再生水经过河床底部介质过程中阳离子的交换吸附机理以及河床底部介质对TN和NO_3~--N的去除效果。根据受水河道周边的地下水水质监测数据,验证了再生水与河床底部介质的水岩相互作用机理。结果表明:再生水资源利用9年以来,地下水中盐度增加;尽管再生水入渗引起了水中K+与河道底部介质中Ca~(2+)之间的交换吸附,但仍然对地下水总硬度具有稀释作用,导致总硬度降低;河道底部介质对再生水中的NO_3~--N具有显著的去除效果,使得地下水中NO_3~--N浓度很低。对于无机组分而言,再生水资源利用对地下水水质基本没有负面影响。     

基于差分卷积的自适应视线估计

文章提出了一种基于差分卷积神经网络的自适应视线估计模型。在模型中,融入头部姿态信息,利用差分卷积设计了一种差分网络(Differential Network,DNet),通过训练该网络来预测眼睛的凝视差异,用以校准初步视线估计结果,进而降低视线估计误差。通过在公开数据集Eyediap上进行验证,并与其他性能良好的视线估计模型进行比较,结果均表明所提出的视线估计模型在头部自由运动的状态下可以更准确地估计视线方向。     

Deep Eutectic Solvents for Boosting Electrochemical Energy Storage and Conversion: A Review and Perspective

The pursuit of sustainable energy utilization arouses increasing interest in efficiently producing durable battery materials and catalysts with minimum environmental impact. As green, safe, and cheap eutectic mixtures, deep eutectic solvents (DESs) provide tremendous opportunities and open up attractive perspectives as charge transfer and reaction media for electrochemical energy storage and conversion (EESC). In this review, the fundamental properties of DESs are first summarized. Then, the important roles that DESs play in various EESC technologies including advanced electrolytes for batteries/supercapacitors, media for the preparation of electrode materials and catalysts, and extracting agents for battery recycling are systematically reviewed. A particular focus is placed on the fundamental understanding of structure–composition–property–performance relationships. Finally, the challenges for the controllable design of DESs for EESC applications and future developments are presented. This review is expected to shed light on developing advanced DESs for next-generation EESC systems.     

一种先进的电网谐波检测方法

本文在传统自适应检测方法的基础上,提出了一种新型的电网谐波检测方法。此法克服其它方法的局限性,不仅能够检测电压谐波,而且能够有效地检测电压的不对称等其它畸变量,仿真和试验结果表明了本文所述方法的有效性,可满足电力系统对电压畸变量检测的要求。同时,这种方法对于谐波电流检测也同样适用。