Impact of Thermal Boundary Resistance on Thermoelectric Effects of the Blade-Type Phase-Change Random Access Memory Device

Phase-change random access memory (PCRAM) is widely regarded as one of the most promising candidates to replace Flash memory as the next generation of non-volatile memories due to its high-speed and low-power consumption characteristics. Recent advent of the blade-type PCRAM with low programming current merit further confirms its prospects. The thermoelectric effects existing inside the PCRAM devices have always been an important factor that determines the phase-transformation kinetics due to a fact that it allows PCRAM to have electric polarity dependent characteristics. However, the potential physics governing the thermoelectric effects for blade-type PCRAM device still remains vague. We establish a three-dimensional (3D) electro-thermal and phase-transformation model to study the influences of thermal boundary resistance (TBR) and device scaling on the thermoelectric effects of the blade-type PCRAM during its “RESET” operation. Our research shows that the presence of TBR significantly improves the electric polarity-dependent characteristics of the blade-type PCRAM, and such polarity-dependent characteristic is found immune to the scaling of the device. It is therefore possible to optimize the thermoelectric effects of the blade-type PCRAM through appropriately tailoring the TBR parameters, thus further lowering resulting power consumption.

The Variation Effect of Electric Current Toward Tensile Strength on Low Carbon Steel Welding with Electrode E7018

The strength of the welding result is strongly influenced by several factors, one of which is the selection of high current. This study aims to determine the effect of high current of welding on the strength of low carbon steel welding joints. The process of welding the material uses the open V seam connection type. The variations of the high current used were 80 A, 100 A and 130 A. The specimen used was a carbon steel plate with code of 1.0038 with thickness of 8 mm and the electrode used was the E7018 electrode with diameter of 3.2 mm. The strength of the welding results is influenced by arc voltage, amount of current, welding speed, amount of penetration and electric polarity. Determination of the amount of current in metal joints using arc welding affects the work efficiency and welding materials. Based on the research, it was found that welding using high current of 100 ampere produced the highest tensile strength value of all test specimens that were given welding treatment and good penetration results.

Rising bubbles as mechanism for scavenging and aerosolization of diatoms

Bubbles rising in clean saline water cause steady displacement of ions at the bubble boundaries that separate anions and cations based on ion mass. Anions of greater mass are resistant to displacement and concentrate on the bubble upper half sphere, while smaller and less massive cations are displaced towards lower pressure of the bottom half sphere. The separation into anionic and cationic domains on the bubble curvatures creates electric polarity that may draw particulates dispersed in the water. Viable diatoms as well as bacteria develop negative charge on outer membranes, that are attracted to the cationic bubble bottom half sphere and pocket. When bubble bursts at the air/water interface the diatoms and bacteria are ejected into the air with initial or secondary jet droplets that are projected upward with a small water column derived from a cationic vortex. Experiments conducted in brackish and oceanic saline water on Nanofrustulum and Cyclotella cells indicated that the averaged concentration in jet droplets compared to the original water volume (here termed the enrichment factor) for aerosolized diatoms may range from 8 to 307.

Analysis of Magnetic Field in Dry-Reed Relay Application Circuit

To the problem of multiple dry-reed relays electromagnetic interference in application circuits, we present an effective method to reduce the electromagnetic interference in this paper. The method is alternating permutation matrix of dry-reed relays. The paper describes the cause of electromagnetic interference of dry-reed relays. Using the offset of electric polarity alternation principle, we put forward the method for reducing electromagnetic interference. The method is applied to a multi-functional physiotherapy instrument. By experiments, experimental result shows that the degree of electromagnetic interference is reduced along with the increase in the number of dry-reed relays.

Summary on Mechanism of Oil Flow Electrification in Power Transformers

The mechanism of oil flow electrification in transformers was described in this paper. The mechanism of oil flow electrification in transformers could be understood from the effect of the oil flow’s movement and the electromotive action of AC electric field. The electric polarity of oil flow and the insulating layer were mainly depended on the state of charged cations and anions in oil, while the surface characteristics of solid materials only played a supporting adsorption role.