Labyrinth effect

On the other hand, the imique barrier properties of nano-dispersed polymeric composites are of interest of polymer combustion due to specific laminar morphology. This type of structure is especially effective in comparison with the other forms of fillers because of the labyrinth effect . Researches in this area will allow defining an influence of diffusion of low-molecular products of pyrolysis on the process of micro-intumescence in a superficial layer of burning polymers. 

High-aspect-ratio nanoparticles, reassembling on the polymer surface during combustion, create an intercalated carbonaceous-silicate residue that lowers the rate of diffusion of the degradation products by a labyrinth effect. ... 

The presence of nanoparticles in a polymer is generally considered to reduce its permeability to gases, because of a labyrinth effect. This feature could be of great interest for coating applications, in particular to improve the moisture resistance of such polymers when they are used in a humid environment. It can be seen in Fig. 

The labyrinth sleeve can be flexibly mounted to permit radial motion for self-ahguiug effects. In practice, a radial clearance of under 0.008 is difficiilt to achieve. 

Labyrinth seals work best when the pump is running. Centrifugal force favors the labyrinth seal s action. Earlier models were only specified for horizontal pump shafts. Later models are designed for both horizontal and vertical pump shafts and effectively perform their function whether the pump is running or off... 

In the tapered labyrinth (Figure 5-5), a fixed labyrinth seals against a tapered shaft. As the shaft moves axially, the clearance of the seal changes. This allows an excess seal gas flow. The resulting venturi effect actually drags the lubricating oil into the process stream. Also, since the tapered shaft seal makes it difficult to provide an effective oil slinger, the problem is compounded. 

Damage to the labyrinth requires replacement of the expander heat barrier or compressor shaft seal. A replacement design (Figure 5-6) uses a replaceable stainless-steel labyrinth mounted on the shaft. Because the seal is not tapered, axial movement of the shaft has little or no measurable effect on seal gas flowrates. Each labyrinth has an integral oil slinger incorporated into the design. Also, each rotating... 

Dry-friction whiri. This type of whip is experienced when the surface of a rotating shaft comes into contact with an unlubricated stationary guide. The effect takes place because of an unlubricated journal, contact in radial clearance of labyrinth seals, and loss of clearance in hydrodynamic bearings. 

The internal structure of the catalyst particle is often of a complex labyrinth-like nature, with interconnected pores of a multiplicity of shapes and sizes, In some cases, the pore size may be less than the mean free path of the molecules, and both molecular and Knudsen diffusion may occur simultaneously. Furthermore, the average length of the diffusion path will be extended as a result of the tortuousity of the channels. In view of the difficulty of precisely defining the pore structure, the particle is assumed to be pseudo-homogeneous in composition, and the diffusion process is characterised by an effective diffusivity D, (equation 10.8). 

The design and necessary calculations for the labyrinth calorimeter with turbulent air flow but low heat losses, have been presented earlier (7). See Figure 1. The advantage over micromethods such as DSC is that effects of sheet density and caliper of fiber entities... 

The intricacy of the intact animal body is further illustrated by the example of the cytokine, tumor necrosis factor (TNF). Table 16.2 shows the spectrum of biologically active molecules that are induced by TNF and Table 16.3 lists the wide variety of biological effects observed in animals to which TNF has been administered. Figures 16.1 to 16.3 show the labyrinth of biochemical cross-talk within and among cells in the body. 

Mechanism of Action Ananticholinergicthat reduces labyrinthine excitabilityand diminishes vestibular stimulation of the labyrinth, affecting the chemoreceptor trigger zone. Therapeutic Effect Reduces nausea, vomiting, and vertigo. 

Cinnarizine is an H 1-receptor antagonist and a calcium channel blocker used for the treatment of vertigo and emetic symptoms due to Meniere s disease and related labyrinth disorders. It is also effective in motion sickness. It is used for peripheral and cerebral vascular disorders, because of its calcium channel blocking properties. 

Non-contact seals with defined narrow clearances, such as labyrinth seals in turbo-machines (Fig. 4.1-47 A), are less problematic owing to the relatively low differential pressures however, the fluid should not have an erosive effect. Differential pressures up to several hundred bar occur at the axial-thrust compensation pistons of centrifugal pumps and compressors, but the fluid expansion is distributed over the many labyrinth stages. 

With dry-running, or sparsely lubricated piston compressors, the use of piston rings made of PTFE composites (Fig. 4.1-49) has proved to be effective as an alternative to non-contact labyrinth seals, but without any limitations with regard to the gas properties. 

The aim of this Art is to discover the source of long life and riches, two foundations upon which the happiness of this human existence rests. It has always been a mystery and those who have treated of it, have in all times spoken of it, as a Science, the practice of which contains something surprising, and the result of which partakes of the nature of the miracle in itself and in its effects. God, the Author of Nature, whom the Philosopher proposes to imitate alone, can enlighten and guide the human mind in the search for this inestimable treasure, and in the labyrinth of the operations of this Art. So all these authors recommend one to address one s self to the Creator, and to demand from Him this favor with much fervor and perseverance. 

In addition to their typical lung-injurant effects, these two compounds aI.MO exert a peculiar. elective action on the < rgmis of equilibrium of the boily, Le, the labyrinth of the ear,. so that the vietim. taggiTs and reels and i.s unable to maintain his body balance. For this reason the French rlas. ified these compounds in a. separate cla.H.M and I allecl them lahyrinikic mibslances. 

The effect of the Bonnet transformation on IPMS is to transform the lattice of catenoidal channels - characteristic of IPMS - into helicoidal strips, through a screw operation on the whole surface. For example, the channels in both the P- and D-surfaces are transformed into spiral tunnels in the g)u oid. Due to its intermediate Bonnet angle with respect to the P- and D-surfaces, it lacks straight lines (2-fold axes) and mirror planes. The labyrinths on both sides are enantiomorphic one labyrinth is left-handed and the other right-handed (Fig. 1.21). 

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