Electrical phenomena firing

Regardless of the underlying etiology, all seizures involve a sudden electrical disturbance of the cerebral cortex. A population of neurons fires rapidly and repetitively for seconds to minutes. Cortical electrical discharges become excessively rapid, rhythmic, and synchronous. This phenomenon is presumably related to an excess of excitatory neurotransmitter action, a failure of inhibitory neurotransmitter action, or a combination of the two. In the individual patient, however, it is usually impossible to identify which neurochemical factors are responsible. 

Many apparently mysterious fires and explosions have eventually been traced to static. In spite of the large amount of information about static electricity, it remains a complex phenomenon not often understood and appreciated. Static electricity is a potential source of ignition whenever there is a flammable mixture of gas or dust. 

In this section we will examine the phenomenon of initiation of explosives. Starting with the extant theories, we will see how all methods of initiation are basically thermal in nature. We will then examine the common types of initiating devices and see how the various modes of initiation and the theories that explain them are applied to both design and performance analysis of these devices. We will also examine the interplay of electrical initiator design and electrical firing circuits. 

The maximum heat flux achievable with nucleate boiling is known as the critical heat flux. In a system where the surface temperature is not self-limiting, such as a nuclear reactor fuel element, operation above the critical flux will result in a rapid increase in the surface temperature, and in the extreme situation, the surface will melt. This phenomenon is known as burnout. The heating media used for process plant are normally self-limiting for example, with steam, the surface temperature can never exceed the saturation temperature of the steam. Care must be taken in the design of electrically heated or fired vaporizers to ensure that the critical flux can never be exceeded. 

Neurotransmitters affect receptors in two basic ways. Some bind to receptors which are said to have ionic effects. These receptors, when activated, operate to open tiny pores (ion-channels), allowing electrically charged particles (ions) to enter the nerve cell. When numerous ionic receptors are activated, this can result in either an excitation of the nerve cell (action potential) or, conversely, a calming of the nerve cell (hyperpolarization, which makes it less likely that the cell will fire). Excitation or inhibition depends on which specific type of channel is activated. This phenomenon is responsible for eliciting immediate and transient changes in neuronal excitability (for example, this occurs when a motor neuron is activated and there is corresponding activation of a muscle, or when sensory events are perceived). 

The electron is a universal quantity, as noted in the high-school address of renowned chemist Mulliken [1]. It is a particle, a wave, and an integral part of all matter. We now know that the natural phenomenon observed with marvel by ancient man, fire, sunlight, lightning, and the modern things we take for granted, such as electricity, radio, television, and nuclear power, all involve electrons. 

It has been said that properly used electricity is not dangerous but out of control it can cause harm, if it passes through a human body, by producing electric shock and/or burns. Electricity s heating effect can also cause fire but we will now deal with the electric shock phenomenon. 

Kondo-like behavior was observed in the lanthanide compoimds, typically in Ce and Yb compounds (Buschow et al. 1971, Parks 1977, Falicov et al. 1981). For example, fire electric resistivity in Cej Laj j Cu6 increases logarithmically with decreasing temperature for all the Af-values (Sumiyama et al. 1986), as shown in fig. 1. The Kondo effect occurs independently at each cerium site even in a dense system. Therefore, this phenomenon was called the dense Kondo effect. 

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