An inexact hybrid projection-proximal point algorithm for solving generalized mixed variational inequalities

In this paper, we investigate an inexact hybrid projection-proximal method for solving a class of generalized mixed variational inequalities in Hilbert spaces. We construct a general inexact hybrid projection-proximal point algorithm, in which an inexact relaxed proximal point step is followed by a suitable orthogonal projection onto a hyperplane. Under some suitable conditions concerned with the pseudomonotone set-valued mapping T, the nonsmooth convex function f and the step size λ_k, we prove the convergence of the inexact hybrid projection-proximal point algorithm for solving generalized mixed variational inequalities in Hilbert spaces.     

Fe掺杂LSCCF对中低温固体氧化物燃料电池ITSOFC短期输出性能的影响

柠檬酸盐法制备La0.7Sr0.15Ca0.15Co1-xFexO3-δ(x=0.2、0.4、0.6、0.8)阴极材料。该前驱体在900℃处理2h后,XRD证实已经形成完整的钙钛矿结构衍射峰。随Fe掺杂量增加,XRD谱图衍射峰的位置向小角度发生偏移,粉体的晶粒尺寸逐渐变大。SEM观察La0.7Sr0.15Ca0.15Co1-xFexO3-δ粉体其表面活性较高并出现了一定的团聚现象,颗粒尺寸约为5μm。以La0.7Sr0.15Ca0.15Co1-xFexO3-δ为阴极,在氢气/空气中研究了模压法制备的单电池性能,Fe掺杂量对开路电压的高低不起决定性作用,而最高功率密度随Fe掺杂量增加而降低,在650℃最高功率密度由x=0.2时的351.7mW/cm2降为x=0.8时的231.1mW/cm2。     

检测计算CVT电容量方法探讨

介绍对 CVT(电容式电压互感器 )电容量的测试方法及注意事项。由于计算 CVT电容量比较繁琐 ,本文简化计算方法 ,在现场实际应用较方便准确     

浅谈叶片钢中δ-铁素体含量的控制

以低压末级和次末级叶片用钢0Cr17Ni4Cu4Nb为例,重点分析了影响δ-铁素体形成的因素,采用了兼顾化学成分和热加工温度的方法来预测δ-铁素体的形成,证实了EδF由ECr和ET共同决定,控制低的ECr和ET可以有效限制EδF的含量,实验证明ECr的含量控制在8.5以下,锻造温度控制在1300℃以下可以保证低的EδF。通过降低铁素体形成元素的含量,提高奥氏体形成元素的含量,从而获得较低的铬当量,减少了δ-铁素体的形成,为新型叶片钢的开发设计、制造使用提供了可靠的参考数据。     

Preparation of La0.8Sr0.2Cr0.97V0.03O3 − δ films for solid oxide fuel cell application

La_0.8Sr_0.2Cr_0.97V_0.03O_3 − δ (LSC) is commonly studied as a ceramic interconnect material as well as a coating material for metallic interconnects for solid oxide fuel cell applications. However, it is difficult to sinter this type of material to high density. In order to overcome this problem and to study the material in form of a thin film we have used Pulsed Laser Deposition to obtain a dense, uniform film with the right stochiometry. Investigation of preparation-parameter dependence of the LSC films deposited on a stainless steel substrate during pulsed-laser deposition was carried out. The LSC films were deposited with KrF excimer laser (248 nm) on a stainless steel substrate at different oxygen pressure and substrate temperatures. The substrate temperature (873-1073 K) and the oxygen background pressure (5-20 Pa) were varied in order to obtain optimal growth conditions. The surface morphology and structural information of the films were obtained using scanning electron microscope (SEM) and X-ray diffraction, respectively. Under the optimal preparation-parameter conditions: substrate temperature of 1023 K and an oxygen pressure of 10 Pa the structure of the film agreed with the target structure and the SEM micrographs show that the surfaces are homogeneous, smooth, crack-free and dense.     

发电机定子线棒tanδ影响因素的分析

通过试验和理论计算对影响发电机定子线棒介质损耗的因素进行了分析,结果表明：发电机定子线棒介质损耗因数（tanδ）的大小与线棒导线绝缘结构、防晕结构、线棒几何尺寸、主绝缘厚度等有关,有端部防晕层的线棒其介质损耗比没有防晕层的线棒大;随着防晕层厚度、主绝缘厚度线棒导体尺寸的增加,介质损耗因数将会减小。     

高温铁素体对17-4PH钢压裂泵阀箱寿命的影响分析

采用17-4PH钢制造的压裂泵阀箱,工况相同,材料的化学成分、力学性能相近,但是使用寿命差异巨大。利用失效分析方法,对正常寿命、不正常寿命件取样,进行试验对比分析,证实了高温铁素体的平均含量对于17-4PH钢压裂泵阀箱的使用寿命存在影响,特定位置的局部富集以及高温铁素体的晶粒大小也是17-4PH钢压裂泵阀箱的使用寿命的重要影响因素。对高温铁素体因为腐蚀因素造成压裂泵阀箱加速疲劳失效的原因进行了分析。建议对压裂泵阀箱用17-4PH钢中高温铁素体的指标进行规范。     

Novel cobalt-free tantalum-doped perovskite Ba Fe_(1-y)Ta_yO_(3-δ)with high oxygen permeation

Cobalt-free perovskite-type oxides Ba Fe_(1-y)Ta_yO_(3-δ)(0 ≤ y ≤ 0.2)were synthesized via a simple solid state reaction.The cubic perovskite structure can be obtained when y is over 0.1.Ba Fe_(0.9)Ta_(0.1)O_(3-δ)(BFT0.1)membrane shows the highest oxygen permeation flux,which can reach 1.6 ml·min~(-1)·cm~(-2)at 950 °C under the gradient of air/He.The O_2-TPD results reveal that Ba Fe_(0.9)Ta_(0.1)O_(3-δ)material shows an excellent reversibility and phase structure stability in air.The oxygen permeation flux is limited by the bulk diffusion when the membrane thickness is over 0.8 mm,and it is limited by both the bulk diffusion and the surface exchange when the membrane thickness is below 0.5 mm.Stable oxygen permeation fluxes are obtained during 180 h operation.     

Construction and experimental investigation of the R-δ_f-type welding window

In this study,a new R-δ_f-type welding window on charge parameters is constructed by determining the boundary conditions of the explosive ratio.The R-δ_f-type welding window synthetically considers the explosive properties and material properties,and can quickly determine the explosive charge at different welding materials with different thickness.In order to test the practicability and accuracy of the R-δ_f-type welding window,410 S stainless steel and QSA5 R low alloy steel plates were explosively welded using 15 mm charge determined by the new window.Microstructures of the bonded sections were examined and then shear tests were carried out on the bonded specimens.Microstructural examination showed the joint interface was transformed from micro wavy to small wavy appearance without microstructure defects.Shear tests results showed interfacial shear strength was much higher than that of the national first grade standard.So the R-Sj-type welding window has strong practicability and accuracy and is helpful to the practical production and application of explosive welding composite materials.     

Effect of microstructure on the electrochemical performance of Ni-ScSZ anodes

The effects of NiO powder morphology and sintering temperature on the microstructure and the electrochemical performance of Nickel-scandia-stabilized zirconia (Ni-ScSZ) cermet anodes for solid oxide fuel cells (SOFCs) were investigated. The particle size and agglomeration of the starting powders were found to affect both the microstructure and electrochemical performance of the Ni-ScSZ cermet anodes. The lowest polarization resistance, 0.690 Ω cm² at 700 °C, was measured for the Ni-ScSZ anode prepared with fine NiO powder (~0.5 µm grain size). This was attributed to the increase in the number of reaction sites afforded by the small grains and well-dispersed Ni and ScSZ phases. The effect of the anode sintering temperature was also found to affect the anode microstructure, adhesion with the electrolyte, and consequently anode polarization resistance. The lowest polarization resistance was observed for the anode sintered at 1400 °C and this was 3–5 times lower than the corresponding values for anodes sintered at lower temperatures.