Achieving excellent energy storage density of Pb0.97La0.02(ZrxSn0.05Ti0.95-x)O3 ceramics by the B-site modification

The applications of antiferroelectric (AFE) materials in miniaturized and integrated electronic devices are limited by their low energy density. To address the above issue, the antiferroelectricity of the reinforced material was designed to improve its AFE-ferroelectric (FE) phase transition under electric fields. In this present study, the composition of Zr⁴⁺ (0.72 Å) and Ti⁴⁺ (0.605 Å) at B-site of Pb_0.97La_0.02(Zr_xSn_0.05Ti_0.95-x)O₃ ceramics with orthogonal reflections are synthesized via the tape-casting method. These ceramics are modified to enhance their antiferroelectricity by reducing their tolerance factor. A recoverable energy storage density W_rec 12.1 J/cm³ was obtained for x = 0.93 under 376 kV/cm, which is superior value than reported until now in lead-based energy storage systems. Moreover, the discharge energy density can reach 10.23 J/cm³, and 90 % of which can be released within 5.66 μs. This work provides a new window and potential materials for further industrialization of pulse power capacitors.     

刮板输送机减速箱箱体模拟分析

为了解决刮板输送机减速箱箱体振动损坏的问题,利用数值模拟软件对箱体静力学进行分析,确定了输出箱螺栓孔为受力薄弱点,同时对固有频率振动云图进行分析发现,由于共振现象箱体出现平移振动.当传动系统出现振动时,造成齿轮在啮合时出现冲击受力,此时齿面的受力呈现不均匀性.最后对额定工况下的箱体最大动应力曲线呈现波动的态势,波动的应力值围绕14.1 MPa进行上下幅动,与0.0388 s的应力云图呈现一致,波动应力最大值为18.6 MPa,为刮板输送机减速器箱体优化提供一定的参考.     

Self-healing,elastic and deformable novel composite phase change polymer based on thermoplastic elastomer SEBS for wearable devices

Journal of Materials Science - Form-stable composite phase change materials (C-PCMs) prepared by microencapsulation method and porous matrix adsorption method need for compression molding after...     

Structure variation and energy storage properties of acceptor-modified PBLZST antiferroelectric ceramics

Energy storage capacitors with high recoverable energy density and efficiency are greatly desired in pulse power system. In this study, the energy density and efficiency were enhanced in Mn-modified (Pb_0.93Ba_0.04La_0.02)(Zr_0.65Sn_0.3Ti_0.05)O₃ antiferroelectric ceramics via a conventional solid-state reaction process. The improvement was attributed to the change in the antiferroelectric-to-ferroelectric phase transition electric field (E_F) and the ferroelectric-to-antiferroelectric phase transition electric field (E_A) with a small Mn addition. Mn ions as acceptors, which gave rise to the structure variation, significantly influenced the microstructures, dielectric properties and energy storage performance of the antiferroelectric ceramics. A maximum recoverable energy density of 2.64 J/cm³ with an efficiency of 73% was achieved when x = 0.005, which was 40% higher than that (1.84 J/cm³, 68%) of the pure ceramic counterparts. The results demonstrate that the acceptor modification is an effective way to improve the energy storage density and efficiency of antiferroelectric ceramics by inducing a structure variation and the (Pb_0.93Ba_0.04La_0.02)(Zr_0.65Sn_0.3Ti_0.05)O₃-xMn₂O₃ antiferroelectric ceramics are a promising energy storage material with high-power density.     

高泉背斜地层压力测井多参数综合解释与异常高压成因

目前国内外地层压力测井解释方法较多,但大多数方法基于欠压实沉积理论并局限于单一的地层岩性,尤其是针对盆地边缘山前深层构造,单一测井参数确定地层压力误差较大,且无法解释沉积压实机制以外的异常高压。为此,将多种异常高压机制相关的测井参数进行综合解释,建立适合山前复杂构造的地层压力测井多参数计算模型,评价准噶尔盆地南缘高泉背斜高探1井的地层压力剖面,其计算结果与钻井实测数据吻合,相对误差小于3.00%.同时,基于原始沉积加载—卸载过程力学原理,利用地层压力测井多参数分析判别出高泉背斜深层各层系异常高压的形成机制。     

基于双层修正无迹卡尔曼的水下节点定位算法* .txt

摘要：针对水下无线传感网络中运动节点定位精度低的问题，提出了一种新的基于双层修正无迹卡尔曼的水下节点定位算法(DLMUKF)。该算法利用下层无迹卡尔曼滤波算法对节点状态进行预测，根据各信标节点的测距传播时延对预测的节点状态进行修正。运用上层无迹卡尔曼滤波算法对修正后的状态进行新的预测与修正。仿真实验中，DLMUKF算法的平均定位误差约为传统多边定位算法的15%，约为基于无迹卡尔曼滤波（UKF）定位算法的16%，受节点运动时间与速度的影响最小。通过实验证明DLMUKF算法能更充分利用实际距离值，可以有效减小运动节点的定位误差。 .txt     

Evaluation of fluctuating voltage topology with fuel cells and supercapacitors for automotive applications

To develop a single‐stage power conversion topology in which energy storage devices can be directly coupled, a fluctuating voltage topology is applied, leading to lower cost and more compactness with the absence of DC/DC converters. This paper investigates such a topology for automotive applications where fuel cells are directly connected to the DC bus of the inverter, resulting in fluctuating voltage across the DC bus. Further, a supercapacitor pack is also introduced to maintain the power capacity and voltage stability. The hybridization principle and practical application of such a topology are then discussed in the time domain and frequency domain. Furthermore, the transient power requirement is decomposed to design the size of fuel cells and supercapacitors. Simulation results from the modeling of the fuel cell‐supercapacitor powertrain demonstrate the feasibility and effectiveness of this topology. The supercapacitors can serve as a low‐pass filter for the fuel cells. In conclusion, the peak power requirement can be successfully achieved because of the lowered system impedance, and the fuel cells only need to supply the average power.     

电解水制氢技术及其催化剂研究进展

随着社会经济的发展，能源和环境问题日益受到人们的广泛关注。氢能因其能量密度高、绿色无污染、储量丰富、应用广泛等优点，被认为是21世纪理想的清洁能源。电解水制氢是一种清洁的生产技术，在“双碳”的背景下得到蓬勃发展，其关键挑战在于开发高性能的析氢反应（HER）电催化剂，以降低水分解的过电势。详细介绍了目前主流的电解水制氢技术，分析了各技术的自身特性和优劣势，重点总结概括了HER催化剂的研究进展，最后对电解水制氢技术及其催化剂的发展方向进行了展望。     

Interfacial polymerization of poly(2,5‐dimethoxyaniline) and its enhanced capacitive performances

The poly(2,5‐dimethoxyaniline) (PDMA) were synthesized through interfacial polymerization method using three various organic solvent/water reaction systems. As comparison with conventional chemical polymerized PDMA, the interfacial polymerization can produce uniform nanoparticular PDMA, especially for using high density (higher than water) solvent as organic phase. The capacitive performances of interfacial polymerized PDMA can be benefited from its uniform morphologies and loose packing structure. The specific capacitance of interfacial polymerized PDMA using carbon tetrachloride is 194 Fg^?1 at current density of 50 mA cm^?2, which has 59% enhancement over 122 Fg^?1 of conventional PDMA at the same current density. The energy density of interfacial polymerized PDMA is 39 Wh kg^?1 at current density of 5 mA cm^?2 and the power density is 28,421 W kg^?1 at current density of 50 mA cm^?2. The energy density has improvement in different extent as comparison with that of conventional PDMA. The enhanced capacitive performances can be attributed to the increased ionic conductivity induced by the loose molecular packing structure and uniform morphology produced by the interfacial polymerization process. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40666.     

新型静电除尘装置在电子玻璃生产线的应用

介绍了新型静电除尘设备在超薄玻璃生产线的优势,系统分析了老式结构的缺陷,随着超薄玻璃的广泛应用,此设备是不可或缺的一个关键装置。新型结构的设计及应用,极大提高了玻璃生产的质量。