Molecular weight vs. relative

Fig. 2 Molecular weight vs. relative viscosity Polymers were off-the-shelf Occidental Chemical Co. commercial products, as well as our experimental high molecular weight PVC produced in small batches at Occidental Chemical Co.

Figure 9. Plot of molecular weight vs. relative amount of alcohol end groups for hydrolyzed Estane and Estane/NP/Irganox at several humidities at 70°C.

As an example of a potential limitation, the drugs listed in Figure 1 have rather low molecular weights and relatively similar in molecular size. However, their skin permeation rates vary as much as 100 folds (2 mcg/cm /hr for fentanyl vs. 200 mcg/cm /hr for ephedrine). This difference in skin permeability will be reflected in the size of TDD system required to deliver the effective daily dose (Table I). A TDD system having a drug-releasing surface area of 90 cm is expected to be required for the delivery of diethylcarbamazine at a daily dose of 215 mg/day. From the standpoint of practical applications, a TDD system of this size would not be neither desirable nor economical. 

Molecular weight vs. conversion curves as followed by GPC vfc. polystyrene standards indicate that relatively high molecular weights are obtained at tow conversions (Mn 20,000 for the polymerization of 2fi 4000 for 3500 for 2bX This supports a chain growth mechanism. Figure 3 shows a comparison of the Mw vs. time curve for 2a coiq>ared to the expected molecular weights calculated for a step growdi process. 

One can see the M procedure has a parallel to either g (s) vs. s or c(s) vs. s in sedimentation velocity where the data are transformed from radial displacement space [concentration, c(r) versus r] to sedimentation coefficient space [g s) or c(s) versus s]. Here we are transforming the data from concentration space [concentration relative to the meniscus j(r) versus r] to molecular weight space [M r) versus r]. 

The log Mn vs. count calibration curve is shown on Figure 5. This is a fairly linear calibration curve, but it covers only a relatively narrow molecular weight range of 145,000 to 317,000 g/mole. Although we have sought to prepare higher MW samples for this purpose, we inadvertently obtained polymers with bimodal MWD s and did not use them for this calibration. 

The molecular masses of heme catalases are usually significantly higher as compared with peroxidases. If expressed in Lg-1s-1, rate constants for the Fem-TAML activators when compared with catalase from beef liver, which has a molecular weight 250,000 gmol-1 (Table IV, entry 13) (89), look very impressive, viz. 17 L g 1 s-1 for 11 vs. 22 L g 1 s 1 for the enzyme. Nevertheless, the catalase-like activity of the Fem-TAML activators can be suppressed by the addition of electron donors -it is negligible in the presence of the substrates tested in this work. In Nature, catalases display only minor peroxidase-like activity (79) because electron donors bulkier than H202 cannot access the deeply buried active sites of these massive enzymes (90). The comparatively unprotected Fem-TAML active sites are directly exposed to electron donors such that the overall behavior is determined by the inherent relative reactivity of the substrates. 

Fig. 3 SDS-PAGE Photograph Separation (Lane Mr and A) and activity staining (Lane B and C) of the crude filtrate of Funalia trogii. Lane Mr standard molecular weight markers ([3-galactosi-dase, 118.0 kDa bovine serum albumin, 79.0 kDa ovalbumin, 47.0 kDa carbonic anhydrase, 33.0 kDa P-lactoglobulin, 25.0 kDa and lysozyme, 19.5 kDa). Relative mobilities of the standard markers vs. common logarithms of their molecular masses were plotted.With the linear regression output, the molecular masses of the proteins in the crude filtrate were estimated (taken from [18])...

Fig. 2.1. Semilogarithmic plot of molecular weight (Mr) of marker proteins vs relative mobility (Rf) of marker proteins in gels of different acrylamide concentrations %T. Proteins 1 aprotinin (6.5 kD) 2 lysozyme (14.5 kD) 3 soybean trypsin inhibitor (21.5 kD) 4 carbonic acid anhydrase (31 kD) 5 hen ovalbumin (45 kD) 6 bovine serum albumin (66 kD) 7 phosphorylase b (97.4 kD) 8 8-galactosidase (116 kD) 9 myosin (205 kD)...

In contrast to template polycondensation or ring-opening polymerization, template radical polymerization kinetics has been a subject of many papers. Tan and Challa proposed to use the relationship between polymerization rate and concentration of monomer or template as a criterion for distinguishing between Type I and Type II template polymerization. The most popular method is to examine the initial rate or relative rate, Rr, as a function of base mole concentration of the template, [T], at a constant monomer concentration, [M]. For Type I, when strong interactions exist between the monomer and the template, Rr vs. [T] shows a maximum at [T] = [M]q. For type II, Rr increases with [T] to the critical concentration of the template c (the concentration in which template macromolecules start to overlap with each other), and then R is stable, c (concentration in mols per volume) depends on the molecular weight of the template. 

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