Project drawings

Among the various ways in which the staggered and eclipsed forms are portrayed, wedge-and-dash, sawhorse, and Newman projection drawings are especially useful. These are shown for the staggered conformation of ethane in Figure 3.2 and for the eclipsed conformation in Figure 3.3. 

From the projection drawings below, it is obvious that the lone pair is anti to a C-C bond in F and a C-H bond in G. Table 50 lists the relative rates for deuterium exchange in some substituted cyclohexanes. In all cases, the equatorial proton exchanges at a much faster rate. 

FIGURE 7.24 Schematic structural projection drawings of (a) ALPO-5 and (b) VPI-5. 

Fig. SO. Projection drawing, viewed along [001] of the structure of zeolite omega (synthetic mazzite). There are two distinct tetrahedral sites, one more (A) and one less (B) accessible via large channels. The unit cell is enclosed within the dashed lines.

Using Fischer projections, draw the product of the reaction of D-mannose with... 

Plate 7—Lattice image of -BaCrOj showing corrugative pattern of Ba03 due to chch stacking (from ref. 67). A projection drawing is... 

Fig. 3. Projection drawings of (a) ABOy perovskites and (b) A2BO4 oxides with K2NiF4 structure. Projection drawings of n = 2 and n = 3 members of the series AO(ABOy) are shown in (c) and (d). Projection drawing of hypothetical (AO)2(ABO i)2 is shown in (e). After Tilley, Ref. (45).

Figure 9-25. Atomic arrangement in the 2Zn-insulin crystal. The smaller projection drawing shows the molecular packing in the insulin hexameters. Courtesy of Dorothy Hodgkin [37],...

A document distribution matrix is typically employed in project designs that indicate what documentation is to be provided to the company s personnel for review. A suggested document distribution matrix is provided in Table 14. This distribution matrix may supplement the facility or project drawing distribution matrix. 

All project drawings are normally drawn on specially printed sheets, with the company name, project title and number, drawing title and identification number, drafter s name and person checking the drawing, clearly set out in a box in the bottom-right corner. Provision should also be made for noting on the drawing all modifications to the initial issue. 

In each case, draw the compound, determine what three groups are on each of the carbons to be placed in the Newman projection, draw the Newman projection with the bonds for the front carbon emanating from the center of the circle and those of the back carbon coming from the perimeter, and put the three groups on each carbon. Rotate between staggered and eclipsed conformations to get the extreme forms. 

Fig. 1. Projection drawing of the trigonal complex containing three planar ligands. The heavy lines represent the ligands, whose molecular planes have been rotated by 45° relative to the XY-plane, defined by the central ion and the ligating atoms. The (-f) and (—) mean above and below the XY-plsne. The projection in this way has the full symmetry D3 of the complex.

Using Newman projections, draw the most stable conformer for the following ... 

Figure 9. Projection drawing of the hydrogen-bonded urea ribbons in 1.1. Portions of a urea ribbon and a composite ribbon are indicated. Broken lines represent hydrogen bonds, and atom types are distinguished by size and shading.

Figure 1. Projection drawings of dimeric a-D-giucan chain segments linked 1,4 (a) and 1,6 (b) (O) oxygens or hydroxyls (o) hydrogens (%)carbons and ( ) hy-droxymethyi groups. Conventions relating to torsion angies , f, and a and other structural features are given eisewhere (1).

Figures 13 and 14 depict mutually orthogonal projection drawings of a particular dectran chain conformation consistent with the preceeding energy surface. The chain is quite disordered and undergoes abrupt changes in direction. It displays no obvious propensity for pseudohelical propagation and is, moreover, quite ccmpact relative to the amylosic chain with = 1.8 and a...

Comparison of projection drawings and calculated chain dimensions for amylose, linear "dextran", and pullulan chains shows that the a-1,6-linkage is a source of considerable conformation freedon in D-glucan chains v ich incorporate this linkage. Experimental studies of the coil dimensions of pullulan and other polysaccharides containing a-1,6-linkages will be required to refine the parameters of the theoretical model for this linkage. 

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