基于STA-LSSVM的槽电压优化方法

针对铝电解过程中,槽电压的参数调节主要采用“试探法”、过于依赖技术员、耗时长等问题,提出了一种基于状态转移算法(State Transition Algorithm, STA)的槽电压优化方法。首先,采用灰色关联度分析方法确定槽电压模型的输入变量;然后,基于改进的最小二乘支持向量机(Least Square Support Vector Machine, LSSVM)建立槽电压软测量模型;最后,采用状态转移算法对槽电压优化控制模型进行实验,获得槽电压优化值和一组优化操作参数。结果表明,建立的槽电压软测量模型具有较高的预测精度,STA算法可寻到3.819 7 V的优化槽电压值,相较于优化前降低了115.8 mV,每吨铝直流电耗降低了363 kW·h,实现了槽电压的优化控制,达到了较好的节能降耗目的。     

联网型高耗能电解铝工业电网源荷协调平抑风电功率波动控制策略

对于含有大规模新能源接入的联网型高耗能工业电网,新能源功率波动势必产生联络线功率波动以及额外备用容量费用,不利于工业电网经济运行。通过对工业电网内部火电机组与电解铝负荷联合控制进行建模,提出源荷协调平抑风电功率控制策略。基于模型预测控制方法,将电解铝负荷和火电机组调节范围以及响应速率作为约束条件,以平抑风电功率波动为控制目标,优化电解铝负荷和火电机组的有功功率调节量,减少由风电功率波动引起的联络线备用容量。以云南文山地区某个工业电网为例进行仿真,结果表明所提的源荷协调控制策略可以有效实现对工业电网内部风电功率波动的平抑,限制与大电网联络线上的有功功率交换。     

吹砂、抛光及其电解腐蚀后处理对单晶高温合金表面组织和再结晶行为的影响

采用吹砂处理、砂带抛光、毡轮抛光3种表面处理使铸态单晶(SX)Ni基高温合金叶片表面形成塑性变形层,对叶片表面变形层进行电解腐蚀实验,然后进行标准热处理,研究了单晶高温合金叶片表面处理的变形层及其电解腐蚀后显微组织。结果表明:3种表面处理的铸态单晶高温合金叶片表面变形层深度分别约为6,3.5μm和2μm,并在吹砂处理和砂带抛光的表面变形层周围存在显微裂纹;表面变形层电解腐蚀过渡区内存在大量γ′变形组织,且3种表面处理的塑性变形残存量依次递减,而变形层完全电解腐蚀区内无塑性变形痕迹;标准热处理后,变形层未电解腐蚀区存在凹陷特征和再结晶晶粒,但无塑性变形痕迹;变形层完全电解腐蚀区无明显凹坑和再结晶晶粒。     

In-situ synthesis of TiO2 nanostructures on Ti foil for enhanced and stable photocatalytic performance

TiO_2 nanostructures with strong interfacial adhesion and diverse morphologies have been in-situ grown on Ti foil substrate through a multiple-step method based on conventional plasma electrolytic oxidation(PEO) technology, hydrothermal reaction and ion exchange process. The PEO process is critical to the formation of TiO_2 seeding layer for the nucleation of Na_2Ti_3O_7 and H_2Ti_3O_7 mediates that are strongly attached to the Ti foil. An ion exchange reaction can finally lead to the formation of H_2Ti_3O_7 nanostructures with diverse morphologies and the calcination process can turn the H_2Ti_3O_7 nanostructures into TiO_2 nanostructures with enhanced crystallinity. The morphology of the TiO_2 nanostructures including nanoparticles(NP), nanowhiskers(NWK), nanowires(NW) and nanosheets(NS) can be easily tailored by controlling the NaOH concentration and reaction time during hydrothermal process. The morphology, composition and optical properties of TiO_2 photocatalysts were analyzed using scanning electron microscope(SEM), X-ray diffraction(XRD), photoluminescence(PL) spectroscopy and UV–vis absorption spectrum. Photocatalytic tests indicate that the TiO_2 nanosheets calcined at 500?C show good crystallization and the best capability of decomposing organic pollutants. The decoration of Ag cocatalyst can further improve the photocatalytic performance of the TiO_2 nanosheets as a result of the enhanced charger separation efficiency. Cyclic photocatalytic test using TiO_2 nanostructures grown on Ti foil substrate demonstrates the superior stability in the photodegradation of organic pollutant, suggesting the promising potential of in-situ growth technology for industrial application.     

Improved Tribocorrosion Properties of Ti6Al4V Alloy by Anodic Plasma Electrolytic Oxidation

Ti6Al4V alloy has good corrosion resistance due to the formation of the passive oxide films on the surface of Ti6Al4V alloy. However, Ti6Al4V alloy has poor tribocorrosion resistance in the seawater environment. Herein the present work, plasma electrolytic oxidation (PEO) with the electrolyte of glycerol and sodium borate is used to generate PEO coatings on the surface of Ti6Al4V alloy to improve its tribocorrosion properties. The microstructure and tribocorrosion properties of PEO coatings are investigated by using scanning electron microscopy, X-ray diffraction, and tribometer, respectively. The growth kinetics and the tribocorrosion mechanisms of PEO coatings are discussed in detail. It is shown in the results that PEO coatings deposited on the surface of Ti6Al4V alloy are composed of rutile and anatase phases. The surface hardness and thickness of PEO coatings are enhanced with the increase of the voltage and time. The wear rate of Ti6Al4V alloy with PEO coatings is significantly reduced in artificial seawater.     

电解极化渗流传感器极化特性研究

针对岩土体渗流原位监测的需求,介绍了一种利用电解极化进行示踪测量的传感器基本原理和制作方法.提出了传感器极化性能测试方法,通过实验研究了传感器的极化特性及其对示踪源的影响,优化了电解电压和电解时间.结果表明:在极化达到稳态前,示踪源的强度随电解电压和电解时间的增加而增加,示踪源的位置随电解时间的增加而变化;在极化达到稳态后,示踪源的强度达到最大,且强度和位置均不随电解电压和电解时间的变化而变化,最佳的电解电压为9V,电解时间为4s.     

基于ARMA模型的工业电容退化状态研究方法

随着中国制造2025计划的推广,工业电源正处于高速发展期,大型铝电解电容的需求越来越大.电容的故障会令工业流水线中断,产生极大的损失,因此工业电容的寿命预测（RUL）具有重要意义.本文通过对铝电解电容充电状态EIS频谱分析,建立电容的状态的量化模型.根据电容状态量化数据,建立ARMA电容退化预测模型.最后通过美国航天航空局的等效串联电阻EIS频谱数据集进行验证.结果表明ARMA电容退化模型对铝电解电容的状态预测有很大的准确性.     

锡盐着色膜颜色与氧化膜中Sn含量的关系

对锡盐电解着色膜的颜色深浅与氧化膜中Ｓｎ含量两者之间的关系进行了研究。此外还探讨了锡盐电解着色液中镍离子和亚铁离子在电解着色过程中所起的作用。     

Crystallization characteristic of glass-ceramic made from electrolytic manganese residue

Electrolytic manganese residue (EMR) is a waste from electrolytic manganese industry that contains high concentration of toxic substances. Since the EMR disposal in landfill sites has a serious environmental impact, new ways of EMR utilization are being sought. Considering the melting of EMR to a glass at high temperature was a relatively less energy-intensive process, EMR was first made into a base glass and then the ground base glass was heat-treated in a certain procedure to make a glass-ceramic and the crystallization process was studied. It was determined by X-ray diffraction (XRD) that the primary crystalline phases of the EMR glass-ceramic were diopside and anorthite, which formed the surface crystallization mechanism with a crystallization activation energy of 429 kJ/mol. Scanning electron microscopy (SEM) observation showed that a layer of small spherical particles with an average size of about 0.5 μm were covered on the glass matrix surface, and among them there were some big particles. The low melting temperature and crystallization activation energy make it promising to reuse EMR for glass-ceramic production.     

Al-Si合金的等离子电解氧化及膜层组织性能研究

为提高铝合金材料在高温下的使用性能,采用等离子电解法在锆盐体系和锆盐-钇盐复合体系中于铝硅合金表面制备了陶瓷层.分析了电解液浓度及成分对起弧电压、膜层厚度、组织及隔热温度的影响.研究结果表明:两种电解液体系中随电解液浓度的增大,起弧电压降低,陶瓷层厚度和隔热温度先增大后减小.与锆盐体系相比,锆盐-钇盐体系中起弧电压显著降低,膜层厚度与隔热温度提高.锆盐体系陶瓷层中生成了常温下稳定的t-ZrO2,锆盐-钇盐体系涂层中则生成了立方相的c-Y0.15Zr0.85O1.93.制备的两种陶瓷膜层与传统的硅酸盐膜层相比,其表面孔洞较少,锆盐-钇盐体系相对于锆盐体系其陶瓷层更加均匀、致密.