Self-coiling

Crystalline nanorings, literally closed circular nanoparticles with a hollow centre, were first prepared from zinc oxide in 2004 by a spontaneous self-coiling process from polar nanobelts.44 Semiconductor nanorings and indeed interestingly shaped nanoobjects in general, promise much in the way of applications as tools to probe fundamental physical phenomena and as nanoscale sensors, transducers, and resonators. 

Jiang Xi-Kui (1988) Hydrophobic-lipophilic interactions. Aggregations and self-coiling of organic molecules. Accts Chem Res 21 362- 367... 

The inset in (c) is an enlargement of a local region, displaying the contrast produced by the uni-radius, loop-by-loop, self-coiling nanobelt, (d) A low magnification TEM image... 

Self-coiling of elongated apolar molecules may exert significant effects on organic reactivity. As demonstrated by Jiang et these effects occur only in water-rich media... 

Jiang, X. K., Fan, W. Q. and Hui, Y.-Z., The effect of hydrophobic—lipophilic interactions on chemical reactivity. 4. A case of 17-membered neighboring group participation compelling evidence for self-coiling,... 

X. K. Jiang, Acc. Chem. Res., 21, 362 (1988). Hydrophobic-Lipophilicity Interactions. A r ation and Self-Coiling of Organic Molecules. 

The basic features of folding can be understood in tenns of two fundamental equilibrium temperatures that detennine tire phases of tire system [7]. At sufficiently high temperatures (JcT greater tlian all tire attractive interactions) tire shape of tire polypeptide chain can be described as a random coil and hence its behaviour is tire same as a self-avoiding walk. As tire temperature is lowered one expects a transition at7 = Tq to a compact phase. This transition is very much in tire spirit of tire collapse transition familiar in tire theory of homopolymers [10]. The number of compact... 

Electrolysis cell. This is shown in Fig. VI, 31, 1 and is almost self-explanatory. The cylindrical cell of Pyrex glass (6" long by 2 " diameter) is cooled by immersion in a cooling bath. The electrodes consist of two platinum plates (4 cm. X 2-5 cm. X 0-3 mm.), which are placed about 2 mm. apart. The temperature of the electrolyte is maintained at 30-35° by means of the internal cooling coil and also by immersion of the cell in ice-water. A current of 1 5-2 0 amperes is passed until the electrolyte becomes slightly alkaline, which normally takes about 20-50 per cent, longer than the calculated time on the basis of the current and the amounts of acid employed. It is advantageous to reverse the direction of the current occasionally. 

A simple coil (even a straight length of cable will serve the same purpose, unless it is too long) as shown in Figure 23.28, will provide a self-inductance when a sinusoidal current is passed through it. We will make use of such a coil to control the excessive currents. The induced inductance in such a coil can be expressed by... 

For obtaining a self-inductance of 42.93 pH consider a coil of 15 cm mean diameter (r= 7.5 cm) made of the same cable that is connecting each capacitor bank through the switching device. 

L = self-induced inductance of the coil in henry N = number of turns of the coil... 

Systems prone to frequent voltage variations Capacitor elements are non-self-healing and are generally provided with internal fuses An inductor coil may not be necessary with such capacitors... 

Since acceleration is the second derivative of displacement, a piezoelectric accelerometer sensor with an integrator becomes a velocity transducer. This arrangement is gradually superseding the self-generating mo ing-coil velocity sensor (where a coil of wire moves relative to a magnetic field). 

Air handling unit A self-contained unit for the introduction or removal of air from a space. It consists of one or more of the following plant items heating or cooling coils, filters, fans, damper provision for mixing and recirculation, humidification controls, and acoustic treatment. 

The plasma is initiated by a spark from a Tesla coil probe and is thereafter self-sustaining. The plasma itself has a characteristic torroidal doughnut shape... 

Flow-induced degradation is intimately related to the nonequilibrium conformation of polymer coils and any attempt to interpret the process beyond the phenomenological stage would be incomplete without a sound understanding of chain dynamics. To make the paper self-contained and to provide a theoretical basis for the discussion, we have included some fundamental models of polymer dynamics in the next section which may also serve as a guideline for future work in the field of polymer degradation in flow. For the first-time reader, however, this section is not absolutely necessary. Further, any reader familiar with molecular rheology or interested only in experimental results can skip this section, only to go back whenever a reference is needed. 

It is expected, however, that the Gaussian representation is inadequate in transient elongational flow, even if the chain is only weakly deformed. During a fast deformation, the presence of non-equilibrium effects, like internal viscosity , noncrossability and self-entanglements will stiffen the molecular coil which is now capable of storing a much larger amount of elastic energy than that predicted from Eq. (113). 

Minich E.A., Nowak A.P., Deming T.J., and Pochan, D.J. Rod-rod and rod-coil self-assembly and phase behavior of pol3fpeptide diblock copolymers. Polymer, 45, 1951, 2004. 

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