Spherical silica particles with mean diameter 350 nm, 500 nm and 1000 nm were used to modify o-cresol-novolac epoxy resin (ECN) at a ranging constant weight fraction from 0 to 20 wt%. The effects of particle size and fillers content on the impact strength, flexural modulus, dynamic mechanical analysis (DMA), coefficient of thermal expansion (CTE), dielectric properties and bulk resistivities of epoxy composites filled with spherical silica particles were investigated. The results revealed that the impact strength and flexural modulus showed significant improvements with the addition of spherical silica particles. The glass transition temperature (Tg) of composites was higher than that of pure epoxy. The maximum increment of Tg was 34 °C by the addition of 2 wt% D500. The CTE of the composites with different size silica exhibit much lower dimension changes than that of pure epoxy. The dielectric constant was decreased with the addition of spherical silica particles. However, the particle size exhibited weakly effect on the dielectric properties. The bulk resistivities of the composites have greatly improved compared to the pure epoxy and increase with decreasing the particle size.
In this study is the use of the generator excitation system design parameters for distributed fieldbus technology and real-time data display module record, will transfer to the field bus data processing and real-time storage of a design. Generator current and terminal voltage and other electrical parameters by the CAN bus pass, when a failure occurs, the fault current and other electrical parameters display, and store it to MRAM or FRAM memory, and also through the external communications port to be transferred to PC and other networks. System uses magnetic resistance random access memory, ferroelectric memory extends the storage capacity, so that fault recording function can be achieved; application PIT and RTC, the timing accuracy of a millisecond, improve the recording wave function
This paper presents a current orientation of the rotor doubly-fed motor speed control system of the simple vector control method, mainly through the detection of rotor current to control the rotor voltage and rotor current phase or reversed. When the double-fed speed, if the rotor and the rotor voltage vector vector always super-synchronous operation or sub-synchronous operation, we can guarantee the rotor side of the power factor is 1, which can reduce the capacity of the rotor side converter, reducing system costs. This paper introduces the basic principles of the system and composition, and finally gives the system simulation and experimental results
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.