消除输电线路绝缘定相试验中强感应电的方法研究

绝缘定相试验是输电线路新投运或改造后的一项重要工作。然而,架空线路的强感应电严重干扰了试验的准确性,使其无法为试验结论提供切实、可靠的判据,甚至会烧毁试验设备。对现有的试验方法进行改进,在实际操作的测量回路中,在线路侧并联一只远大于线路绝缘电阻的纯电容,有效解决了现场强感应电对试验工作的危害,保障了试验的准确性和完整性。

DIMENSIONLESS ANALYSIS AND LOCATION OF ELECTRIC FIELD INDUCED BY MAGNETIC COIL

A model of magnetic stimulation is presented for analysis of the spatial distributions of the electric field induced by magnetic coils.Dimensionless analysis is introduced and makes the factors influencing the magnitude of electric field into two parts:c (represents the stimulation conditions),and E 0 (reflects the geometry of coil).By 3 D simulation of the induced electric field of two kinds of coils,the effect of magnetic stimulation can be demonstrated and the factors influencing stimulating focality and depth are identified.The principles for determining the electric field magnitude,focality and magnetic stimulation depth when designing a reasonable coil and stimulator and achieving ideal stimulating effect are discussed.

Light Actuation of Liquid in Optofluidics

Optofluidics is the integration of optics and microfluidics(so-called lab on the chip). Wherein the actuation of liquid is a key technic. In a variety of methods for controlling microscale liquid, the light actuation is particularly interesting. The light actuation offers a novel way to control the flow of fluids for biomedical and biotechnological applications, etc.. The complexity and cost of devices sometimes may be greatly reduced by using complete optical control and may be more flexible in operation than other methods. However the light actuation of liquid is a burgeoning field as well as optofluidics. There is lots of work to do. Here we systematically describe four mechanisms for the light actuation of liquid based on the following points: optoelectrowetting, photothermal effect, radiation pressure, photosensitive substance.

Approaches to Stable Operation of Shaftless Centrifugal Pump

The shaft-less impeller of the centrifugal pump, which is driven by the magnetic induction, was developed. Theimpeller rotates under the floating condition without any control device. The floating condition of the impeller isrealized by utilizing the pressure in pump casing. The pump performance and the rotational behavior of the impellerwere investigated experimentally. It has found that the floating position of the impeller become quite unstablein a partial flow rate operation. And the pressure distribution at the casing wall affects the rotational posture ofthe impeller. This paper presents the effect of the casing treatment on the rotational posture of the impeller and thepressure distribution. The reasonable casing treatment is available for the stable rotational posture of the impeller.

Full-temperature covered switching material with triple optic-dielectric states in a lead-free hybrid perovskite

Optic-electric responsive materials have attracted much attention for their applications in temperaturesensing,actuators,and memory switches.However,it is a challenge to integrate various functions to form multifunctional responsive materials.As molecule-based hybrid materials usually consist of organic and inorganic components,the introduction of multiple functions can be achieved through structural construction.Thus far,even though fulltemperature cover is required for device applications,fulltemperature covered multi-switchable hybrid materials have rarely been successfully synthesized.Herein,the dynamic[(CH3)3NOH]+cation and luminous center Mn(II)were introduced to form a hybrid material[(CH3)3NOH][Mn Cl3],showing multiple temperature-responsive behaviors.Upon temperature change,it exhibits multi-state dielectric switching response and intensity or peak shift response of luminous in full-temperature range(low,room,and high temperatures).These responsive behaviors are triggered by the motion or reorientation of[(CH3)3NOH]+cations and inorganic framework.Overall,the switchable photoelectric material has potential applications in multiple encrypted storage and sensor devices.