Static electricity defined

If a material of polar molecules, such as water, is exposed to a fixed or static electric field, the molecules will all rotate in an attempt to orient themselves in the direction of the field. The magnitude of separated charges of a polar molecule is defined as the dipole moment, and determines the strength of interaction with the field. The dipole moment is also a measure of the dielectric constant e. A symmetrical molecule, with no dipole moment, is said to be non-polar and does not react with an electric field. If an electric field impinging upon a polar molecule is alternating, the molecules will rotate, following reversals of field. 

This procedure of calculating perturbed distribution functions is of use if the molecules of the medium are under the effect of a static electric field only and if the system is in well-defined conditions of thermodynamic equilibrium. If, however, the system is acted on by an alternating field... 

When the molecule is perturbed by a static electric field, nuclear electric shieldings can be defined [8-11], which are related to IR intensities [12-14],... 

The choice of (Oj, CO2... (static or not) defines the various non-linear optical processes and in Table 1 some of these are listed. Until now there has been no consensus with regards to abbreviations for these processes, so I take the liberty of making a set of recommendations. I have tried to make the abbreviation short, so that, e.g., dc implies the presence of a static electric field (rather than dc-EF), and I have tried to avoid repugnant sounds such as EFISH or OKE. It should be remarked that one can always permute the subscripts a, p, y... along with the frequencies -over-states formulas for P and y), consequently, the components of OR are just different components of dc-P, as are dc-OR and dc-K. It is obvious that processes 3,7, and 8 are just... 

The tendency of textile polymers to accumulate static electrical charges is related to their electrical resistance. With solid materials, the electrical resistance is defined as the resistance between opposite faces of a 1 m cube. With textile polymers, for reasons similar to those given earlier, it is more convenient to express the resistance of fiber filaments by... 

Static electricity, or what is known as electrostatic charging, can be defined as an excess or deficiency of electrons on an insulated or nonearthed surface. Such charging can occur through friction or contact of surfaces with... 

This chapter first derives the basic equations relating dielectric behavior to polymeric structure. The equations defining the change in dielectric behavior with frequency and temperature are then developed. The application of dielectric phenomena to polymeric structures is described next with particular emphasis on piezoelectricity. Finally, the relation between static electricity and polymer structure is discussed. 

A dielectric may be defined simply as a volume of material placed between the plates of a capacitor for examination by an applied electric field. Traditionally, there is an important difference between dielectric and bioimpedance measurements with respect to the role of water. Etymologically, a dielectric is a material that the electric field penetrates (Greek dia meaning through). Conductors do not allow static electric field penetration, and basically a perfect dielectric is a substance without free charges. Synonyms for a perfect dielectric may then be an insulator or a nonconductor antonyms may be a conductor or an electrolyte. 

As demonstrated in Fig. 7, which shows the results for a pipette checked using the gravimetric method, the coefficient of variation (CV, defined as the ratio of the standard deviation to the mean) for a run consisting of ten measurements of a given volume increases considerably when the dispensed liquid volumes are less than 5 pi. Evaporation, buoyancy, vibration, and the effects of static electricity are the primary causes of these results. A possible alternative method to determine microscale droplet volumes is one based on measurement of the concentration of a liquid solution. Two practices, also recommended by the ISO standard [5], are commoifly used, namely, the photometric and titrimetric methods. 

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