Special effects

Having introduced the basic types of firework, from rockets to gerbs and wheels, it remains to consider the special effects that are essential features of large display fireworks and, indeed, of many of the smaller ones. 

In this section we would like to briefly describe a number of less developed and in some cases unexplained ideas and phenomena based on electric fields, which have been or may be used in combination with chemical (micro)reactors. They are posed here as possible suggestions for further research. 

One of the applications of electric wind is in aerodynamics, in which field it has been an important objective to modify airflow around an obstacle in order to reduce drag. The advantage of flow control by an 

A direct application to chemical process technology of the principle of electric wind is in electrostatic precipitators (Leonard et al.,1983) and electrocyclones for size separation of particles in powder technology (Nenu et al., 2009). Electrostatic precipitators applied to exhaust gas cleaning have recently been reviewed 0aworek et al., 2007). A particularly interesting development is that of a small electrocyclone with a diameter of 75 mm (Shrimpton and Crane, 2001). With this device it was shown that the separation quality of the smallest size particles with a diameter below 38 pm doubled upon application of the electric wind. Later experiments performed with submicron silica particles demonstrated that classification of such particles is possible by use of an electrical hydrocyclone (Nenu et al., 2009). 

Electrospray has been used for many different applications, such as the deposition of paints and coatings on metal surfaces and the deposition of metal nanoparticles and biomolecules on biosensor surfaces, and in a miniaturized version also as a propulsion mechanism in microsatellites (see also the section on electric wind). One particularly interesting application is in fuel atomization, that is, a finer fuel aerosol and atomization will give a higher combustion efficiency and less pollutant emission, which is caused by the effect that finer droplets increase the total surface area on which combustion can start (Lehr and Hiller, 1993). 

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Special effects of water on Diels-Alder reactions... 

Breslow supported this suggestion by demonstrating that the cycloaddition can be further accelerated by adding anti cliaotropic salts such as lithium chloride, whereas chaotropic salts such as guanidium chloride led to a retardation " "" ". On the basis of these experiments Breslow excluded all other possible explanations for the special effect of water on the Diels-Alder reaction " . 

Mechanistic studies have tried to unravel the origin of the special effect of water. Some authors erroneously have held aggregation phenomena responsible for the observed acceleration, whereas others have hinted at effects due to the internal pressure. However, detailed studies have identified two other effects that govern the rate of Diels-Alder reactions in water. 

SPEC benchmark Special-duty propane Special effects Specialty chemicals... 

Kinetic. Kinetic pumps, which act by impelling a fluid from one location to another, can be centrifugal, regenerative turbine, or special effect (see Fig. 1). 

Theatrical Pyrotechnics or Special Effects. Many spectacular visual and audible effects are produced for stage presentations of both music and drama, and many motion pictures and television shows incorporate pyrotechnic and explosive special effects to Hven up the presentation. These spectacular effects are a combination of pyrotechnics, explosives, combustion, and electronics. After the effects are filmed or videotaped, they are often enhanced by slow-motion replay and by the addition of more exciting noise. A real explosion is over in milliseconds, and hence there is a need for electronic enhancement to create a more spectacular effect on the screen. 

For the purpose of special effects, combinations of adhesives or glue resins might be used, e.g. ... 

A common principle for the prt)duction of smoke for this purpose is to cvat>-orate a mineral oil by electrically hearing it and to mix the vapor into air. The oil will then condense and form a mist. Different such apparatus can be found on the market. Some of them are aimed for the visualization t f airflow but others are intended lor special effects in theaters, discotheques, etc. Figure 12.3 shows one such apparatus commonly used for this purpose. 

Pharmacology. Lycorine was first examined by Morishima wl found it relatively non-toxic to mammals. Given per os or subcutaneous, to the dog or cat, it causes, in small doses, salivation and in large dos vomiting and diarrhoea. It has no special effect on the blood pressure death seems to be due to a generalised collapse. Post mortem —hyper m and ecchymoses in the stomach, intestine, pulmonary pleura and end... 

The bromination of 4,5-j -dihydrocortisone acetate in buffered acetic acid does not proceed very cleanly (<70%) and, in an attempt to improve this step in the cortisone synthesis, Holysz ° investigated the use of dimethylformamide (DMF) as a solvent for bromination. Improved yields were obtained (although in retrospect the homogeneity and structural assignments of some products seem questionable.) It was also observed that the combination of certain metal halides, particularly lithium chloride and bromide in hot DMF was specially effective in dehydrobromination of 4-bromodihydrocortisone acetate. Other amide solvents such as dimethylacetamide (DMA) and A-formylpiperidine can be used in place of DMF. It became apparent later that this method of dehydrobromination is also prone to produce isomeric unsaturated ketones. When applied to 2,4-dibromo-3-ketones, a substantial amount of the A -isomer is formed. 

The special effect of an or -nitro group, noted by Chapman et in reactions with primary or secondary amines but not with tertiary... 

Other considerations In addition to the above general factors affecting inhibitor application and performance, there will be other special effects relating to particular types of systems, e.g. in oil-production technology. Some of these are referred to in appropriate cases in the following section. 

The permutations of 0[H] have a special effect on the rows of the matrix (1.37) if a permutation moves an element of one row into another row, then the permutation moves all the elements of the one row into the other row. The rows of (1.37) are imprimitive domains of 0[H]. The permutations of 0[H] which leave the r imprimitive domains invariant (the gross permutation of which is the identity) form a subgroup it has order it is the direct product H xHxHx...xH with r factors and is a normal subgroup of C [H], with factor group. 

Many commercially available detergents are suitable for this purpose, and some manufacturers market special formulations for cleaning laboratory glassware some of these, e.g. Decon 90 made by Decon Laboratories of Portslade, are claimed to be specially effective in removing contamination due to radioactive materials. 

We shall consider only forces between systems of moderate size which are in their ground electronic states. Dahler and Hirsch-felder8 have discussed the additional complications when excited states are introduced. Yos, Bade, and Jehle42 gave special consideration to London forces between macromolecules but found it difficult to determine the magnitude of the special effects they noted. 

Some Special Effects in the Flow of Filled Polymers... 

Wiping Paint is applied conventionally, then paint is wiped off Paint is either totally removed, remaining only in recessed areas, or is partially removed for special effects such as woodgraining. Standard spray-paint setup with a wipe station following. For low production, wipe can be manual. Very highspeed, automated equipment available. 

Roller coating Raised surfaces can be painted without masking. Special effects like stripes. Roller applicator, either manual or automatic. Special paint feed system required for automatic work. Dryers... 

Inserted nameplates Unit cost high Labor cost high Investment moderate Partially limited Restricted Not critical Good durability Longer molding cycles Allows three-dimensional as well as special effects. 

Solids, multicolor, overall or partial decoration, special effects such as woodgraining possible. 

The special salt effect is a constant feature of the activation of substrates in cages subsequent to ET from electron-reservoir complexes. In the present case, the salt effect inhibits the C-H activation process [59], but in other cases, the result of the special effect can be favorable. For instance, when the reduction of a substrate is expected, one wishes to avoid the cage reaction with the sandwich. An example is the reduction of alkynes and of aldehydes or ketones [60], These reductions follow a pathway which is comparable to the one observed in the reaction with 02. In the absence of Na + PFg, coupling of the substrate with the sandwich is observed. Thus one equiv. Na+PFg is used to avoid this cage coupling and, in the presence of ethanol as a proton donor, hydrogenation is obtained (Scheme VII). 

More systematic study of the dynamics of radicals in solution should now be possible using CIDNP. Investigations so far reported have indicated that the rates of very rapid chemical reactions and other dynamic processes undergone by radicals can be measured in a crade way greater refinement should be possible. Special effects have been predicted for reactions in thin films (Deutch, 1972). Moreover the time-scale of polarization is such that the technique may prove capable of throwing new light on the dynamics of excited states. 

The actions of zinc and aluminium differ. In general, metal ions such as zinc merely serve to neutralize the acid and are present in solution as simple ions (Holroyd Salmon, 1956 O Neill et al., 1982). But aluminium has a special effect in contrast to zinc, it prevents the formation of crystallites during the cement-forming reaction in zinc phosphate cements. 

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