Electric helicity

A very important property is that the magnetic and electric lines of an electromagnetic knot are the level curves of the scalar fields 4>(r, t) and 0(r, f), respectively. Another is that the magnetic and the electric helicities are topological constants of the motion, equal to the common Hopf index of the corresponding pair of dual maps constant with dimensions of action times velocity. 

The magnetic and electric helicities of this knot turn out to be... 

As was shown in Section II, the magnetic and the electric helicities of any radiation electromagnetic field are equal. Moreover, in the case of the topological model, the helicities of the knots verily... 

One of these topological constants of the motion is the electromagnetic helicity, defined as the semisum of the magnetic and electric helicities, which is equal to the linking number of the force lines... 

Fig. II, 17, 2 illustrates a fractional distillation unit f for use with glass helices. The column is provided with an electrically-heated jacket the resistance shown in the Figure may be replaced by a variable transformer. The still head is of the total-condensation variable take-off type aU the vapour at the top of the column is condensed, a portion of the condensate is returned to the column by means of the special stopcock (permitting of...

Small batch retorts, heated electrically or hy combustion, are widely used as carburizing furnaces and are applicable also to chemic processes involving the heat treating of particulate sohds. These are mounted on a structural-steel base, complete with cyhnder, furnace, drive motor, burner, etc. Units are commercially av able in diameters from 0.24 to 1.25 m and lengths of 1 to 2 m. Continuous retorts with helical internal spirals are employed for metal-heat-treating purposes. Precise retention control is maintained in these operations. Standard diameters are 0.33, 0.5, and 0.67 m with effec tive lengths up... 

For most of the rotary compressors in process service, the driver is an electric motor. Compressors in portable service, however, particularly the helical-lobe compressor, use internal combustion engines. Many of the rotary compressors require the high speed that can be obtained from a direct-connected motor. The dry type helical-lobe compressor is probably the main exception as the smaller units operate above motor speed and require a speed increasing gear which may be either internal or external (see Figure 4-1). The helical-lobe compressor is the most likely candidate for a driver other than the electric motor. Aside from the portables already mentioned, engines are used extensively as drivers for rotaries located in the field in gas-gathering service. Steam turbines, while not common, probably comprise most of process service alternate drive applications. 

The toroidal and helical forms that we consider here are created as such examples these forms have quite interesting geometrical properties that may lead to interesting electrical and magnetic properties, as well as nonlinear optical properties. Although the method of the simulations through which we evaluate the reality of the structure we have imagined is omitted, the construction of toroidal forms and their properties, especially their thermodynamic stability, are discussed in detail. Recent experimental results on toroidal and helically coiled forms are compared with theoretical predictions. 

The most promising way to study the electrical conductivity of a single nanotube is, thus, tightly dependent on the development or/and the adaptation of modern nanolithographic techniques. The goal to achieve is within reach and a detailed study of the electronic properties with reference to helicity and diameter will provide instrumental information about these fascinating materials. 

The helical lobe, or screw, compressor is shown in Figure 36.7. It has two or more mating sets of lobe-type rotors mounted in a common housing. The male lobe, or rotor, is usually direct-driven by an electric motor. The female lobe, or mating rotor, is driven by a helical gear set that is mounted on the outboard end of the rotor shafts. The gears provide both motive power for the female rotor and absolute timing between the rotors. 

Recommended methods for assessing the corrosivity of waters, including flowing potable waters, are described in ASTM 02688 1983. Three procedures are described in which test specimens in the form of wires, sheets or tubes are placed in pipes, tanks or other equipment. The test assembly for the first of these consists of three helical wire coils mounted in series on, and electrically insulated from, a supporting frame. The assembly must be installed so that flow is not disturbed and turbulence and high velocities, e.g. of more than 1 -53 ms , are avoided. A minimum test period of 30 days is recommended. Procedures for the other specimen forms are given in the standard. 

Heisenberg-type descriptions for two observers, 667, 668 Heitler, W., 723 Helicity operator, 529 Hermitian operator, 393 Hermitian operator Q describing electric charge properties of particles, 513... 

Turbine flow meters are composed of some form of rotary device such as a helical rotor, Pelton wheel or a vane mounted in the flow stream. The fluid passing the rotor causes the rotor to turn at an angular velocity which is proportional to the flow velocity and hence the volumetric flowrate through the meter. The rotary motion of the rotor is sensed by some form of pick-up device that produces an electrical pulse output. The frequency of this signal is proportional to the flowrate and the total count of pulses is proportional to the total volume of liquid passed through the meter. 

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