Bowl shape

Rotors are made of titanium or aluminum and may be cylindrical or bowl-shaped (see Fig. 12). Larger bowls reach 100,000 G smaller units reach 250,000 G. The tubular rotors permit feed rates up to 60 L/h at 150,000 G or 120 L/h in a larger unit at 90,000 G. Such centrifuges may be used to separate relatively large quantities of vkal material from larger quantities of cellular and subceUular matter, as, for example, in the production of vaccines (see Vaccine technology). 

Scbalen-bau, m. shell structure, -blende, /. fibrous sphalerite, -entwickelimg, /. (Pho tog.) tray (or dish) development, schalenfdrmig, a. bowl-shaped, dish-shaped, cup-shaped shell-like. 

SchUssel,/. dish bowl pan. schusselfdnnig, a. dish-shaped, bowl-shaped. Schusselzinn, n. pewter, schussfest, a, bulletproof. 

Cratering the formation of small bowl-shaped depressions in a paint or varnish film. 

Cross section of the Cl engine piston with a typical quiescent-bowl shape and a centrally located high-pressure fuel irtjector. 

Blcycllc (7) is bowl-shaped and epoxidatlon ought to take place on the outside of the bowl. Further disconnection of the enone in (7) reveals a 1,4-diketone, which must be ais if cyclisation to (7) is to occur. Reconnection to (9) fixes the stereochemistry. 

In practice simple alkenes give poor cycloaddition so diene (49) was the chosen starting material and the aldol was protected and hydrogenated to give (48). Note that (50) is emphatically bowl shaped (Chapter T 34) so that substituents (OR) or reagents (Hg) prefer to be on the outside of the bowl. The regioselectivity of the addition of Cl2C=C=0 to the diene (49) is correct. Synthesis ... 

Table 1.3 contains values for two 3d cases. At KsCuFg, ATreplirreg) contributes about 40% of the total stabilization, but at Ni (aq) only 15%. This is because in the first transition series, the nephelauxetic effect increases substantially when the oxidation state increases from -i-2 to -e3. The relatively small contribution for the M (aq) ion explains why text books use this example to explain the double bowl shapes AErep(irreg) is almost exactly cancelled by the sum of AEso and ATrix, so the total stabilization is nearly equal to the orbital stabilization energy. In most other cases, A rep(irreg) is much more important and may play an important role in sustaining the Irving-WilUams rule in complex-ing reactions [32, 33]. 

Pu-Erh tea is produced in Yunnan Province by the action of microbiological fermentation on green tea. Noted for its earthy flavor, it is often processed into cakes, such as Tuo-cha or bowl-shaped tea. 

Strapped tetramines show conformationally rigid coordination environments that can lead to novel stability properties. The coordination properties of bowl-shaped cavities or adamanzanes such as the ligand l,5,9,13-tetraazabicyclo-[7.7.3]nonadecane (95) were investigated.745 The... 

Dimeric (Me2AuCl)2 has been used to close the cationic adamantane cage of a bowl-shaped iVV-donor ligand with a [m-Me2Au]+ unit. The two chlorine atoms are accommodated in the [m-Me2AuGl2] counterion (Equation (7)).34... 

Launay, N., Caminade, A.M., and Majoral, J.P. (1997) Synthesis of bowl-shaped dendrimers from generation 1 to generation 8./. Organomet. Chem. 529, 51-53. 

Further examples of cavitand-type structures include hw-cyclo-triveratrylene derivatives such as (257) (Gabard Collet, 1981 Canceill, Lacombe Collet, 1986) and the bowl-shaped hosts represented by (258) - the base of the bowl is formed by the four methyl groups. Once again, the shape of these molecules is maintained by conformational constraints. Cavitand (258) is able to accommodate simple solvent molecules such as dichloromethane and chloroform. Moreover, its cavity is large enough to form inclusion complexes with up to four molecules of water (Moran, Karbach Cram, 1982). 

Stable S-nitrosothiols and S-nitrososelenols have also been generated by attaching bowl-shaped aryl substituents to the nitrogen centre.193,194 The alkyl derivative (Me3Si)3CSeNO is prepared by nitrosation of (Me3Si)3CSeH with tert-butylnitrite.195... 

Fig. 2. Schematic representation of the most common architectures of metalated container molecules. The open boxes represent active coordination sites at the metal ions. The bowl-shaped representation of the host molecules should not be confused with the one used for the cyclodextrins.

Cylodextrins (CDs) are a class of chiral cyclic oligosaccharides that have molecule-sized cavities. They commonly comprise between six and eight D-glucopyranoside units that are linked via a-l,4-glycosidic links. Their bowl-shaped form is generally represented as a cylindrical funnel by analogy to the calixarenes family. There is a large number of cyclodextrin derivatives in the... 

Bowl-shaped coordination compounds have been assembled spontaneously from 10 small components, such as six (en)Pd2+ units and four 2,4,6-tri(3-pyridinyl)triazene moieties the overall structure approaches 3oA <00JA2665>. A different construct was derived from the 4-pyridinyl isomer and Pt(bpy)2+ and shown to facilitate self-assembly within the coordination... 

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