采用DOE实验设计方法改进电容器级铌粉酸洗工艺

采用DOE实验设计方法,对制备电容器用铌粉的酸洗除杂工艺进行研究,确定了影响铌粉性能的关键因素是酸洗除杂工艺使用酸的浓度和酸洗时间。通过关键因素的全因子正交试验,对产品质量和工艺参数进行量化分析,确定最佳的酸洗工艺,可有效减低和控制电容器级铌粉中的主要C、O非金属及Fe、Ni、Cr金属杂质含量,降低电容器级铌粉的漏电流和损耗,提高电容器级铌粉的性能。     

一个机组供电的晶体管稳流电源

1983年我们制作了一台由机组供电的晶体管稳流电源,取代原苏制BT-4稳流装置,作为ЭГ-2.5质子静电加速器分析磁铁的激磁电源。主要技术指标为:(1)额定输出直流电压100 V;(2)额定输出直流电流30 A;(3)电流调节范围0—30 A;(4)电流稳定度为±1.4×10~(-5)(当负载变化±10%时),±1.0×10~(-5)(当电网电压变化±10%时);(5)长时间漂移为2.3×10~(-5)/h,5.26×10~(-5)/8 h;(6)电流纹波为8.7×10~(-5)。     

一种带有泵升电容的新型高增益升压直流变换器

为了满足分布式发电系统中必须把太阳能、燃料电池和蓄电池输入的低压直流转换为高压的要求,在传统型升压直流变换器的基础上,提出了一种基于双电感和泵升电容的新型拓扑结构。该拓扑结构利用电感和电容的并联充电、串联放电特性,较好地实现了低占空比条件下高电压增益的目标。最后,分析了该拓扑结构在3种不同电感条件下的工作原理,并通过仿真验证了上述理论分析的正确性。     

电子式电流互感器高压侧自励源供能方法研究

介绍了一种直接从高压母线获取工作电源的电子式电流互感器结构方案,讨论了‘自励源’设计中的若干问题及应对策略,提出磁场取能方案中的限流‘漏斗结构’,给出了整机实验结果。     

伊敏─冯屯500kV同塔双回线路不平衡度、感应电流及潜供电流研究

本文针对３８１ｋｍ伊敏－冯屯１５００ｋＶ线路中１９０ｋｍ采用同塔双回线布置后可能出现的特殊问题，如双回线布置和换位方式对系统不平衡度的影响，双回线间感应电流以及潜供电流变化问题，进行了分析计算。     

谐波滤波装置在化工生产上的应用

本文介绍了谐波滤波装置在化工生产的应用和效果，通过滤波装置对高次谐波进行滤波，降低电网电压的畸变率，减少高次谐波电流对电力系统网络其他电气设备的危害，并且对其低功率因数进行无功功率补偿，以达到节约能源之目的。     

Study of amperometric diffusion solid-state electrolyte cell operating regimes

Different operating regimes are considered for operation of an amperometric diffusion solid-state electrolyte cell for measuring the volume fraction of oxygen. The design of an oxygen sensor is described. Experimental results confirm the efficiency of the proposed diffusion solid-state electrolyte cell for measuring oxygen in the range of 98–100%. Translated from Izmeritel’naya Tekhnika, No. 10, pp. 64–65, October, 2008.     

变电站不锈钢金属膨胀节泄漏原因分析

从化学成分、断口电镜扫描、X射线能谱和金相试验等方面,分析了沧州供电公司某变电站电流互感器不锈钢膨胀节泄漏的原因,认为泄漏是不锈钢膨胀节外表面点状电化学腐蚀所致,而该膨胀节表面状态的不连续性,周围潮湿的空气介质及空气介质中富含S、Cl等元素,是造成膨胀节外表面点状电化学腐蚀的主要原因。     

消防安全管理现状与消防监督管理模式探讨

文章从我国消防安全管理的现状出发,简要分析了现存的消防安全管理问题,并就消防监督管理工作的创新模式提出意见,以期为相关工作者带来一定的参考价值。     

Characterization of Inhibitory Capability on Hyperpolarization-Activated Cation Current Caused by Lutein (β,ε-Carotene-3,3′-Diol), a Dietary Xanthophyll Carotenoid

Lutein (β,ε-carotene-3,3′-diol), a xanthophyll carotenoid, is found in high concentrations in the macula of the human retina. It has been recognized to exert potential effectiveness in antioxidative and anti-inflammatory properties. However, whether and how its modifications on varying types of plasmalemmal ionic currents occur in electrically excitable cells remain incompletely answered. The current hypothesis is that lutein produces any direct adjustments on ionic currents (e.g., hyperpolarization-activated cation current, I_h [or funny current, I_f]). In the present study, GH₃-cell exposure to lutein resulted in a time-, state- and concentration-dependent reduction in I_h amplitude with an IC₅₀ value of 4.1 μM. There was a hyperpolarizing shift along the voltage axis in the steady-state activation curve of I_h in the presence of this compound, despite being void of changes in the gating charge of the curve. Under continued exposure to lutein (3 μM), further addition of oxaliplatin (10 μM) or ivabradine (3 μM) could be effective at either reversing or further decreasing lutein-induced suppression of hyperpolarization-evoked I_h, respectively. The voltage-dependent anti-clockwise hysteresis of I_h responding to long-lasting inverted isosceles-triangular ramp concentration-dependently became diminished by adding this compound. However, the addition of 10 μM lutein caused a mild but significant suppression in the amplitude of erg-mediated or A-type K⁺ currents. Under current-clamp potential recordings, the sag potential evoked by long-lasting hyperpolarizing current stimulus was reduced under cell exposure to lutein. Altogether, findings from the current observations enabled us to reflect that during cell exposure to lutein used at pharmacologically achievable concentrations, lutein-perturbed inhibition of I_h would be an ionic mechanism underlying its changes in membrane excitability.