Improved chemical stability and proton selectivity of semi-interpenetrating polymer network amphoteric membrane for vanadium redox flow battery application

In this work, semiinterpenetrating polymer network (semi-IPN), consisting of sulfonated poly (arylene ether sulfone) (SPAES) and crosslinked vinyl imidazole grafted polysulfone (VMPSU), is prepared and characterized. FTIR, EDS, and solubility test indicate the successful preparation of amphoteric membranes. The semi-IPN amphoteric membranes exhibit better stability than pure SPAES membrane, as demonstrated by thermogravimetric analysis and ex situ immersion testing results. More importantly, it is shown that the amphoteric membrane can effectively hinder vanadium ion crossover through the membrane, which is attributed to the semi-IPN structure and Donnan exclusion. As expected, the amphoteric membrane containing 20% VMPSU exhibits the highest proton selectivity (6.86 × 10⁴ S min cm⁻³), comparing to pristine SPAES (1.90 × 10⁴ S min cm⁻³) as well as Nafion117 (1.31 × 10⁴ S min cm⁻³).     

计及源荷不确定性的独立型交直流混合微网多能源协调优化调度

传统独立型交直流混合微网的可再生能源供电比例高,但储能和其他可控电源容量有限,易出现切负荷或弃风弃光现象.首先,为提高系统的供能可靠性和可再生能源的消纳水平,设计出一种基于氢储系统实现交流、直流、氢气、热力与天然气能源系统深度耦合的能量枢纽结构;其次,为实现设计系统的多能源协调优化调度,构建出一种计及源荷不确定性的两阶段鲁棒优化模型,模型中第一阶段确定所有能源转换和存储设备的运行状态,第二阶段确定最恶劣场景及各设备出力方案,并且可利用不确定度参数灵活调整调度结果的保守性;然后,基于强对偶理论和大M法将优化模型转换为具有混合整数线性形式的主问题和子问题,并采用列与约束生成算法求解;最后,算例分析结果表明所建模型的合理性,求解算法的有效性以及调度结果的鲁棒性和经济性.     

考虑经济成本的微电网调度运行

为提高微电网经济运行水平,首先以微电网发电成本最小为目标,考虑微电网运行实际约束条件,将蜂群算法运用到并网状态下的微电网经济调度模型中;其次,将对立学习策略初始化种群,改善初始种群质量,同时将Metropolis准则引入蜂群算法,提高跳出局部最优解的概率;最后,以并网状态下的微电网为例,比较未改进蜂群算法与改进蜂群算法优化结果.结果 表明,改进蜂群算法的调度方案降低了微电网的日调度综合成本,同时验证了所改进算法在求解微电网调度优化问题上的有效性与优越性.     

基于局部间隙状况电火花磨削周期的伺服策略

分析了现有的一些电火花磨削伺服策略存在的问题，提出了基于周期性和局部性特点的伺服策略。该策略以回转周期为控制周期，以局部间隙状况为控制的依据，通过极端局部间隙状况控制极端局部表面加工状态，从而控制整个表面优质高效的加工，具有快速修圆和一定的自动寻优功能。     

Hot-Corrosion Resistance of a Sputtered K38G Nanocrystalline Coating in Molten Sulfate at 900°C

The hot-corrosion behavior of a nanocrystalline coating of K38G alloy, prepared by magnetron sputtering and cast K38G in molten 75 wt.% Na₂SO₄+25 wt.% K₂SO₄ at 900°C was studied. The coating eliminated internal sulfidation during the early stage of corrosion as a result of the formation of a continuous and compact Al₂O₃ scale. The nanocrystallization of K38G alloy prolonged the incubation of breakaway corrosion and improved the corrosion resistance of K38G. The relevant corrosion mechanism is discussed.     

Charge-discharge process of MnO2 supercapacitor

Mechanochemical synthesis of α-MnO2 was carried out with KMnO4 and Mn（CH3COO）2 in 1：1 mole ratio. The electrochemical performance of MnO2 electrode was investigated by cyclic voltammograms and alternating current impedance. The charge-discharge process of MnO2 supercapacitor in 6 mol/L KOH was studied within 1.2 V at 200 mA/g, suggesting that it displays double-layer capacibility in low potential scope and pseudo-capacitance properties in high potential scope. It is found that Mn3O4, an electrochemical inert, mainly forms in the initial 40 charge-discharge cycles. During cycling, the pseudo-capacitance properties disappear and the discharge curves are close to ideal ones, indicating double-layer capability. The maximum capacitance of MnO2 electrode is as high as 416 F/g, and retains 240 F/g after 200 cycles. The equivalent series resistance increases from 17 to 41Ω.     

等径角挤压法制备超细晶的研究现状

总结了等径角挤压(Equal Channel Angular Pressing，ECAP)过程中的影响因素、晶粒细化的机理等方面的研究进展，讨论了挤压温度、挤压速度在ECAP过程中对材料的影响，简述了ECAP的变形途径、变形次数对材料晶粒、材料变形量的影响。论述了由等径角挤压方法制备超细晶材料的发展现状并提出了一些需要进一步深入研究的方面。     

氧气喷头的热挤压工艺及模具设计

在设备吨位和闭合高度有限的情况下，设计结构新颖的组合成挤压模具，使315t油压机设备能力得到了有效的发挥；本文所述氧气喷头毛坯生产工艺，具有节材优质高效的特点；对类似零部件挤压工艺及模具结构设计具有重要的参考价值。     

转炉炼钢氧枪枪位自动控制专家系统的实验室研究

在转炉造渣过程中，渣中FeO的含量直接影响到石灰的溶解速度、造渣途径和炉渣的喷溅、返干，在泡沫渣淹没吹炼状态下，调整氧枪枪位可有效地控制渣中FeO的含量。音平控渣系统，可以给出喷溅、返干的趋势，在此基础上，开发氧枪枪位自动控制专家系统，对喷溅、返干进行预测，采用自学习技术给出枪拉操作提示。此系统为氧枪自动控制奠定了基础。     

熔体过热对Ag-Cu合金生长取向的影响

通过对Ag-Cu合金熔体的过热处理，研究了不同生长速率时的平界面的结晶位向，发现高的熔体温度使平面单晶的位向产生分支现象。应用Leonard-Jones势能和团簇概念分析了位向分支的形成原因，表明团簇状态在母相中的分布对结晶取向具有重要作用。