Turns per coil

Table 17.1 Typical ratios of copper to insulation the turns per coil in smaller frame sizes...

So we choose to use silicium microcoil. For example, the LETT [2] can realize 2 layer coils with 21 turns per layer, 7 pm wide by 3 pm thick track,... 

The coiling together of textile staple fibres, yams or threads to give the structure the required degree of strength, extensibility, flex resistance, etc. Twist is designated as so many turns per inch and either right hand (Z) or left hand (S). See S-Twist and Z-Twist. 

Fig. 5. Schematic diagram of coiled-coil periodicities in relation to the numbers of residues per turn, the sequence repeat length, and the number of helical turns per repeat. Transitions caused by the insertion of stutters are marked in green, and transitions caused by stammers in blue. Periodicities for which we found examples in...

Application of Ampere s circuit theorem B dl = /r0/tota to the dotted path (Fig. 9.3(a)) around the coil wound on non-magnetic material gives B = n0nl, where I is the current and n is the number of turns per unit length. However, if the coil is wound on magnetic material then, because amperian currents are now also involved,... 

For an ideal "solenoid," a hollow cylinder of length l, cross-sectional area A, and volume V = Al wrapped by a closely spaced coil of wire with N turns (or n = N/l turns per unit length), the inductance is... 

A chunk of a magnetic ceramic weighing 10 g is attached to the sensitive balance shown in Fig. 15.2a and is suspended in the center of a toroidal solenoid with 10 turns per centimeter. A current of 9 A is passed through the coils. The magnetic field gradient due to the permanent magnet was measured to be 100 G/cm. When the current was turned on, such that H was in the same direction as the... 

At the moment it seems wise not to regard details of possible helical models as too firmly fixed. It may be expected, however, that the number of residues per turn in helical models, if such be applicable to collagen, cannot be chosen without upper and lower limits. Table V is designed to indicate some dimensions of coils with three to six turns per pseudoperiod. It is impossible to entertain a projection per turn less than 4 to 5 A. The rough coil diameters, calculated according to Fig. 31, also cannot be much less than 5 A. Consequently, as columns 2 and 4 show, the coil with six turns per pseudoperiod may be excluded. There must also be sufficient space between adjacent coils, whose separation was calculated above to be 12.0 A. in dry collagen, to accommodate the side chains. Column 5 shows that the coil with three turns offers an excessively tight squeeze in this respect (see Section V, 2), so that all but the models with about four to five turns per pseudoperiod may undoubtedly be eliminated. 

No. of turns per pseudoperiod Axial projection per turn No. of residues per turn Main-chain coil diameter" Available between coils ... 

H Magnetic field strength. Unit ampere per metre, A/m. A field of 1 A/m is produced by an infinitely long solenoid with n turns per metre of coil, carrying a current of 1/n, A. 

Heat leak into the low-temperature region along the two electrical leads of the coil is inevitable however, the magnitude of this heat leak is relatively small. For the sodium coils, assuming one end of the electrical lead at 10 K and the other end at room temperature, about 1.1 kw of heat leak occurs per coil, or 4.5 of the total heat load. This is computed for optimum-sized leads which, for 1 ft length, are 2.2 in. in diameter. If the warm ends of the leads are maintained at liquid-nitrogen temperature, heat leak is about 1/4 of the above values for the optimum lead size of 1.3 in. in diameter. By using smaller conductors and more turns, this heat leak can be reduced. 

For flat spiral (pancake) coils, in which the ratio D /Dj varies for each turn, a different value of coefficient will be obtained for each turn a weighted average based on length per turn is used. 

Variations on the a helix in which the chain is either more loosely or more tightly coiled, with hydrogen bonds to residues n + 5 or n + 3 instead of n + 4 are called the n helix and 3io helix, respectively. The 3io helix has 3 residues per turn and contains 10 atoms between the hydrogen bond donor and acceptor, hence its name. Both the n helix and the 3to helix occur rarely and usually only at the ends of a helices or as single-turn helices. They are not energetically favorable, since the backbone atoms are too tightly packed in the 3io helix and so loosely packed in the n helix that there is a hole through the middle. Only in the a helix are the backbone atoms properly packed to provide a stable structure. 

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