Tulips

Another application areas of microtomography are biology and agriculture. Fig.4a shows an X-ray transmission image through the tulip bulb in wet conditions. Damaged area can be found in the surface of this bulb. Fig.4b shows the reconstructed cross section with information about depth of damaged volume. 

Fig.4.Microtomography of tulip bulb shadow image (a) and cross-sections (b)...

Spring supported tulip contacts (fixed contacts)... 

C Chothia, AM Lesk, A Tramontano, M Levitt, SJ Smith-Gill, G Air, S Sheriff, LA Padlan, D Davies, WR Tulip, PM Colman, S Spmelh, PM Alzari, RJ Poljak. Conformation of immunoglobulin hypervariable regions. Nature 342 877-883, 1989. 

Smokeless Coanda Gas releases at base of elevated tulip create low pressure region. Gas film follows Coanda profile mixes with air and is ignited by pilot. 

Tulpenbaum, m. tulip tree, tumeazieren, v.i. tumefy, swell, tummeln, v.t. exercise, keep moving. — v.r. bestir oneself. 

Missing from this list is Peter McGahey, my developmental editor, who deserves special thanks. He soothed frayed nerves and lifted sagging spirits with his positive, optimistic personality. His good humor provided an extra dose of energy. It also helped to get off topic once in a while to chat about tulip bulbs in the spring and perennials in the summer Thanks, Peter. You were an oasis of calm on many days. 

Pipecolic acid has been isolated and identified by various researchers from several legumes, hops, mushrooms, potato tuber, green pepper, tulip, celery, asparagus, Rhodesian teak, barley, and coconut milk. Grobbelaar et al. 58) isolated large quantities of free (-)pipe-colic acid from Phaseolus vulgaris. 

The fate of areas of south-eastern American deciduous forests which were dominated, before the arrival of the pathogen, by chestnut and species of oak has been traced (Fig. 10) over nearly 40 years (Day Monk, 1974). The demise of chestnut from its standing as a canopy dominant was rapid, taking about 20 years, with a complete failure to return. During this period eeosystem productivity was reduced (as shown by a reduction in tree basal area. Fig. 10). However, the place of chestnut in the forest has been taken by a number of species, in particular oak and tulip tree, which have steadily increased in dominance. The community has clearly changed markedly but the ecosystem as a whole has shown complete recovery, in terms of re-establishing tree basal area. The place of chestnut in the oak-chestnut forests has been taken by other native species. So in the context of conservation, although the loss of chestnut is unfortunate, it has not been at the eost of an invasion of alien species of tree. 

Tulip Flames The Shape of Deflagrations in Closed Tubes.93... 

Tulip Flames in Relahvely Short Closed Tubes.96... 

The dramatic dynamics of the flame-shape change shown in Figure 5.3.1, along with its proposed relationship to the flame instability and flame-generated flow, has periodically sparked an interest in its study. Before reviewing this flame-shape transition phenomenon, it will be useful to trace the history of the "tulip" name and distinguish this particular flame shape from the myriad of others with which it is often equated or confused. 

In 1957, a flame propagating in a long tube under conditions resulting in a deflagration to detonation transition (DDT) was given the name "tulip" by Salamandra et al. [7]. This term was subsequently commonly applied in detonation studies to describe this typical shape [8,9]. Figure 5.3.2 shows a few... 

Rotating camera images of a CO/O2 flame undergoing the inversion from the hemispherical cap flame to an inverted shape that is now considered a tulip or perhaps more accurately a "two-lip" flame. The flame propagates in a 20.3 cm long closed cylindrical tube of 2.5 cm diameter. (Adapted from EUis, O.C. de C. and Wheeler, R.V., /. Chem. Soc., 2,3215,1928.)... 

Comparison between tulips, (a) Image of an actual tulip flower that has been rotated and sized for comparison (b) the tulip shape noted by Salamandra et al. [7] in flames on their transition to detonation and (c) the inverted flame shape identified by Ellis and Wheeler [5] in closed tubes that is now being called a tulip flame. The image to the right is simply a negative of that to its left. 

However, despite this misnomer, when interest in the closed-tube flame of the Ellis-type resurfaced in the mid-1980s, the researchers involved were also aware of the DDT tulips and the name transferred to the cusped laminar flame transition [11-14]. An example of a flame image from this era is shown in Figure 5.3.4, and the "tulip" name is now used routinely to... 

Flame shape images and traces extracted from the high-speed schlieren movie (5000 frames/s) of a stoichiometric methane/air flame going through a tulip inversion while propagating in a square cross-section (38.1 mm on the side) closed tube. 

Tulip Flames in Relatively Short Closed Tubes... 

As mentioned earlier, the tulip flame has been observed under a wide variety of conditions, suggesting that it is a... 

Tulip-flame formation begins simultaneously with the rapid decrease in the flame area that accompanies the flame quench at the sidewalls of fhe combustion vessel... 

The more pronounced the flame-area reduction is, the more pronounced is the tulip-flame transition... 

Formation of a tulip flame is relatively insensitive to mass loss and endwall geometry... 

Taken together, these observations indicate that the basic tulip-flame formahon is a remarkably robust phenomenon that depends somewhat on the overall geometry of the combustion vessel. There is little doubt that the growth of the cusp represents a Darrieus-Eandau instability [33-35] that is stabilized by the thermo-diffusive fransporf af fhe small scales, buf an inferesfing lingering... 

Early attempts to explain the trigger for the tulip flame focused on the pressure wave/flame interactions. This was a natural consequence of the well-documented vibratory behavior of flames seen in the very first streak images recorded [2], and the images of Markstein (like that in... 

Velocity vectors of the gas flow measured using laser Doppler anemometry inside a closed chamber during the formation of a tulip flame. Images of the flame are also shown, though the velocity measurements required many repeated runs, hence, the image is only representative. The chamber has square cross sections of 38.1mm on the side. The traces in the velocity fields are the flame locations based on velocity data dropout. The vorticity generated as the flame changes shape appears clearly in the velocity vectors. 

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