Constriction shape

Flow Nozzles. A flow nozzle is a constriction having an eUiptical or nearly eUiptical inlet section that blends into a cylindrical throat section as shown in Figure 8. Nozzle pressure differential is normally measured between taps located 1 pipe diameter upstream and 0.5 pipe diameters downstream of the nozzle inlet face. A nozzle has the approximate discharge coefficient of an equivalent venturi and the pressure drop of an equivalent orifice plate although venturi nozzles, which add a diffuser cone to proprietary nozzle shapes, are available to provide better pressure recovery. 

Impingement is corrosion caused by aerated water streams constricting metal surfaces. It is similar to erosion corrosion in which air bubbles take the place of particles. The pits formed by impingement attack have a characteristic tear drop shape. 

The orifice, the venturi, and the nozzle are instruments for the measurement of duct or pipe flow rate. A constriction, throttling the flow, is placed in the duct, and the resulting differential pressure developed across the constriction is measured. It is the difference in the geometric shape that characterizes the three devices see Fig. 12.22. 

If the platinum wire is to be used as an electrode it may be preferable not to flatten and shape it as in the Housekeeper method, but to use a mercury cup on the outside of the apparatus (Figure 42, III). The fine wire is fused into a constricted part of a narrow bore tube and the... 

If this area is square in shape, the length of each side needs to be 6.79°5 = 2.6in. We can usually make this somewhat rectangular or odd-shaped too, so long as we preserve the total area. Note that if the area required exceeds 1 square inch, a 2-oz board should be used (as in this case). A 2-oz board reduces the thermal constriction around the power device and allows the large copper area to be more effectively used for natural convection. 

Each chromosome has a constriction point called the centromere, which divides the chromosome into two sections, or "arms." The short arm of the chromosome is labeled the "p arm." The long arm of the chromosome is labeled the "q arm." The location of the centromere on each chromosome gives the chromosome its characteristic shape, and can be used to help describe the location of specific genes. 

It is apparent from Table 1 that the cyclohexadiene ring in 1,2-dihydrocorannule-nes is significantly flatter than either 1,3-cyclohexadiene itself or 9,10-dihy-drophenanthrene due to the constriction imposed by the remainder of the bowl-shaped ring system. Nonetheless, the lack of planarity means that substituents at may adopt either pseudoaxial (pa) or pseudoequatorial (pe) positions. However, the surface of the corannulene system is curved, and, unlike 1,3-cyclohexadiene and 9,10-dihydrophenanthrene, neither the two pa positions nor the two pe positions are equivalent. Thus, substituents in 1 -/ -1,2-dihydrocorannulenes may be (1) endo-pseudoaxial (endo-pa), (2) e do-pseudoequatorial (e/ido-pe), (3) exo-pseudoaxial (exo-pa), and (4) exo-pseudoequatorial (exo-pe), where endo and exo are related to concave and convex orientations, respectively. 

Continuous screw extrusion is another way to form PVC plastisol propellant into the desired size and cross-sectional shape. Simultaneous curing of the propellant is also accomplished. This process has been described fully by Rossen and Rumbel (9) and is only summarized here. Mixed propellant is fed from a casting pot into the feed end of a continuous worm-screw extruder which is fitted at the discharge end of the screw with a device for constricting propellant flow. The action of the... 

Hypanthium tubular or um-shaped, often constricted above and enclosing the ripe fruit endosperm commonly... 

Figure 30-17 (A) Two-dimensional map of the 260-kDa a subunit of the voltage-gated Na+ channel from the electric eel Electrophorus e/ecfns.438 441 (B) Image of the sodium channel protein obtained by cryo-electron microscopy and image analysis at 1.9 nm resolution. In this side view the protein appears to be bell-shaped with a height of 13.5 nm, a square bottom (cytoplasmic surface) 10 nm on a side, and a hemispherical top with a diameter of 6.5 nm. (C) Bottom view of the protein. (D) Axial section which cuts the bottom, as viewed in (C), approximately along a diagonal. From Sato et al.438 Notice the cavities (dark) and domain structures (light). The black arrow marks a constriction between upper (extracelllar) and lower (cytoplasmic) cavities. White lines indicate approximate position of the lipid bilayer. From Sato et al.i38 Courtesy of Chikara Sato.

Lowenfeld12 identified the components of the fight reflex that were controlled by parasympathetic and sympathetic innervation of the smooth muscles controlling pupil diameter. They concluded that the parasympathetic nervous system must be intact to observe the light reflex the sympathetic nervous system influences the shape of the reflex. For example, in the absence of sympathetic innervation, the constriction velocity is increased and the dilation velocity is decreased. Conversely, in situations of increased sympathetic tone, the constriction is sluggish and incomplete, and the pupil slowly returns to its baseline size. The effects of abused drugs on these and other components of the light reflex were studied in the experiment described below. 

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