Caterpillars

R. Richards, "Methanol-Pueled Caterpillar 3406 Engine Experience ia On-Highway Tmcks," V4E Paper 902160, (SP-840), Society of Automotive Engineers, Warrendale, Pa., Oct., 1990. 

An analogy to sHp dislocation is the movement of a caterpillar where a hump started at one end moves toward the other end until the entire caterpillar moves forward. Another analogy is the displacement of a mg by forming a hump at one end and moving it toward the other end. Strain hardening occurs because the dislocation density increases from about 10 dislocations/cm to as high as 10 /cm. This makes dislocation motion more difficult because dislocations interact with each other and become entangled. SHp tends to occur on more closely packed planes in close-packed directions. 

Tree Preservation gypsy moths, caterpillars, borers, leaf miners, mites wounds from pmning or other damage to bark... 

FIGURE 10.36 Adult (left) and caterpillar (right) stages of the cecropia moth,... 

Raupen-antrieb, m. (Mach.) caterpillar drive, -leim, m. Raupenleim (a petroleum product used for protecting trees against caterpillars, etc.). T.N. -schlepper, m. caterpillar tractor. 

Caterpillar IH2 determines the lubricant effect on ring sticking, ring and cylinder wear, and accumulation of piston deposits. 

El-Basil, S. Caterpillar (Gutman) Trees in Chemical Graph Theory. 153, 273-290 (1990)... 

Some insects can protect themselves against the toxins present in their food plants by storing them. One example is the monarch butterfly, the caterpillars of which store potentially toxic cardiac glycosides obtained from a food plant, the milkweed (see Harborne 1993). Subsequently, the stored glycosides have a deterrent effect upon blue jays that feed upon them. 

Example A family of biologically active compounds Isolated from African trees include polygodial (39), an antifeedant which protects the tree against plagues of caterpillars. ... 

Caterpillars and other moulting insects excrete the hormone a-ecdysone which at moulting time becomes hydroxylated to 20-hydroxyecdysone (20-E), which in turn triggers the moulting process enabling the insect to shed its exoskeleton and resume feeding. Rohm and Hass have developed a novel insecticide, tebufenozide (Formula 9.5) which mimics 20-E, binding to the same site. The consequence of this is that the insect stops... 

Kleine Reaktoren mit grower Zukunji, Chemische Rundschau, April 2002 PAMIR study large commercial potential large industrial interest market volume standardization strategic cooperations time horizon potential for pharmaceuticals and fine chemistry Clariant pilot with caterpillar mixer [211],... 

Hessel, V., Lowe, H., Hofmann, C., ScHONFELD, F., WeHLE, D., WeRNER, B., Process development of a fast reaction of industrial importance using a caterpillar micromixer/tubular reactor set-up, in Proceedings of the 6th International Conference on Microreaction Technology, IMRET 6, pp. 39-54 (11-14 March 2002), AIChE Pub. 

Reactor 21 [R 21] Caterpillar Mini Mixer-Tube Reactor... 

Figure 4.22 Second-generation caterpillar mini mixer with splitting plate and improved microstructure geometry [50].

Figure 4.23 Near-ideal multi-lamination flow patterns in the second-generation caterpillar mini mixer as a result of introducing a splitting plate and improving micro structure geometry [50],...

This plate cuts the flow into pieces which are better defined than the poorly defined ones obtained by the first-generation caterpillar mini mixer. In addition, the micro structure geometry was improved by means of simulation. As a result, near-ideal multi-lamination flow patterns were yielded (Figure 4.23), which showed excellent correspondence with simulation [50]. 

Reactor type Caterpillar mini mixer-tube reactor, 1st generation Micro structure in one plate initial depth maximum depth 600 pm 850 pm... 

Mini mixer channel inihal width maximum width 1200 pm 2400 pm Total length of caterpillar mini mixer 19.2 mm... 

P 29] A set-up comprising a steel caterpillar mini mixer and four steel tubes attached was used, being dipped into a cylinder completely filled with a cooling medium (scale-up set-up) [48,108]. By means of a 5/2-way valve, it was possible to switch the reactants to either of the tubes acting as delay loops, differing in inner diameter and hence residence time. 

OS 40] [R 21] [P 29] Using a caterpillar mini mixer inserted in the scale-up setup, a maximum yield of 89% was determined [48]. This is even slightly higher than for the laboratory-scale setup (83%, see above). 

Figure 4.61 Yield of product and side/consecutive products as a function of temperature for the scale-up set-up with a caterpillar steel mini mixer [48],...

OS 40] [R 21] [P 29] A much larger dependence of yield on reaction temperature was observed for the caterpillar mixer-scale-up set-up than for the inter digital mixer-laboratory set-up [48]. At temperatares above ambient, significant decreases in yield of the order of several tens percent were determined. 

Table 4.4 Yields obtained for the target product and side/consecutive products using a laboratory-scale set-up with caterpillar steel micro mixer [48].

A caterpillar steel mini mixer can be connected to conventional tubing, either stainless steel or polymeric, to prolong the residence time. The caterpillar mixer as all types of split-recombine mixers, profits from high volume flows (e.g. 100 1 h and more at moderate pressure drops) at favorable pressure drop (not exceeding 5 bar) as its internal microstructures can be held large [25-28]. 

For a more detailed description of the hydrodynamics of the caterpillar mixer, respective images and the performance of a second-generation caterpillar device see the corresponding section in Section 4.1. 

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