Irradiation time for

Figure 4 Changes in (a) carbonyl index and (b) hydroxyl index versus irradiation time for polystyrene films. O-con-trol -2,4-DHBP -2H-4MBP -2H-4BB X-DHBP-F A-HMBP-F and D-HBBP-F.

Figure 11 (a) Tensile strength (TS), and (b) elongation at break (EB) versus irradiation time for PMMA films X-control ... 

Figure 2. Plot of molecular weights of products vs. irradiation time for the photolysis of 10 A, in benzene B, in the presence of methanol in benzene.

Interestingly, our own studies have revealed that both the shape of the macromolecule and the glass transition temperature, Tg, change with irradiation time. For example, the irradiation of a bimodal commercial sample of polyvinylcarbazole (PNVK) (Fig. 5.31a) in dichloromethane occurred with an initial increase in (the number average) molar mass (M ) and an apparent loss in the bimodal nature of the polymer (Tab. 5.16, Fig. 5.31b). A similar initial increase in has been observed by Price [39] during a sonically induced polymerisation. 

Figure 31. Relative DOC decrease as a function of irradiation time for the four experiments at low DOC0 [experiments 1 (A), 3 ( ), 5 (A), and 7 ( ), Table 3] and control experiments [thermal reaction experiment 10 (O), and direct photolysis experiment 11 ( )] [12].

Photolysis of 413 afforded a trace of dibenzotrithiepin 47 along with 13% yield of 48 (Scheme 87). The sodium borohydride reduction of 413 afforded 414. Photolysis of 414 in CH2CI2 for different time durations afforded different amounts of 47 and 48, the amount of 47 decreasing with increasing irradiation time for example, when the irradiation was done for 12, 24, and 72 h, the ratio of 47 and 48 was found to be 34 32%, 10 63%, and 8 22%, respectively <2000TL1801>. 

Fig. 5 Photosulfonation of LDPE. Surface tension y versus UV irradiation time for non-crosslinked ( ) and crosslinked (A) polyethylene...

Figure 19-7. Yields of SSBs and DSBs induced by 0-4.2 eV electrons on supercoiled plasmid DNA films. The inset shows the dependence of the percentage of circular DNA (i.e. SSB) on irradiation time for a beam of 0.6 eV electrons of 2 nA...

Fig. 27 Irradiation from 180-600 nm (a) UV-Vis spectra recorded at 60 min intervals for the degradation of PHEMA- -PMPS-Z -PHEMA aggregates (b) a plot of A/A0xl00% at Xmax versus irradiation time for various copolymer aggregates...

Figure 30.8 RMS roughness as a function of irradiation time for a PVME-PS blend of 64 36 mol%...

Fig. 2. Polymer fraction vs. irradiation time for a 4-BCMU film, 1300 A thick. Data points are experimental, full curves are obtained for the energy transfer model for various quenching parameters k, = k To (from Ref. >)...

Fig. 65. Plot of hydrogen-production rates versus the irradiation time for [Co(diAMsar)]3+ (i) [Co(diCLsar)]3 (2), and [Co(CLsar)]3 (3) cations with [Ru(bpy)3] cation as sensitizer [384].

FIG. 6.20 UV Vis spectra of LBK film of polymer 38 (80 layers. 20 mN/m), as a function of irradiation time for irradiation vndi UV light = 360 nm) (left) and far irradiation with wsfale light X 440 nm) (right). (Reproduced with permission fntwn reference 93). 

Figure 6. Variation of carbonyl index with irradiation time for LDPE processed for varying times. Processing times in parenthesis.

From the slopes of the plots of conversion versus irradiation time for the photopolymerization of the [98h] isopropanol system, at constant light absorption for a fixed initial chromophore concentration and at various initial isopropanol concentrations, the apparent rate constants k can be determined (Table 24) for different isopropanol concentrations. The plot of the reciprocal of the apparent rate constant versus the reciprocal of the Isopropanol concentration yields a straight line from which the ratio k(j/kj- can be obtained (Fig. 9). The value kj/kj- = 0.23 obtained in Fig. 9 Is in agreement with the value k j/kj- = 0.214 (Table 22). 

Figure 24.7 (a) Semilogarithmic plotsof monomer fraction versus UV irradiation time for the topochemical polymerization of muconates, (b) relationship between relative polymerization rate and degree of shrinking (open circles) or expansion (closed circle) during topochemical polymerization. 

Microphotochemistry is commonly performed under continuous-fiow rather than batch conditions. Consequently, the irradiation time for photochemical processes... 

The occurrence of catalyst deactivation and of the role played by water, was investigated by performing very long reactivity runs at the flow rate of 0.42 cm s-i. Deactivation is not affected by the presence of mass transfer limitations, while the use of a low flow rate allows variations of outlet gas composition to be detected more accurately. Figure 3 reports the fractional conversion of toluene to benzaldehyde versus irradiation time for two long runs carried out in the presence and in the absence of water vapom. For the run in the presence of water, a maximum conversion of 0.19 (corresponding to an... 

Figure 3. Toluene fractional conversion to benzaldehyde versus irradiation time for runs carried out in the presence of water vapour ( ) and in the absence of water vapour (A). Flow rate 0.42 cm s toluene molar fraction 1.3x10. Catalyst amount 8 g. Photon flux SmWcm 2.

In Figure 4 the fractional conversion of toluene to benzene is reported versus irradiation time for the same runs reported in Fig. 3. The presence of water was beneficial for benzene production, but benzene virtually disappeared after 3-4 h of irradiation, independent of the presence of water. 

Figure 4. Toluene fractional conversion to benzene versus irradiation time for the runs reported in Figure 3.

Copolymerization of Propylene with Hexafluoroacetone. The conversion curves of the copolymerization are shown in Figure 12 as a function of irradiation time for equimolar monomer mixtures at 0°, —35°, and — 78°C. The copolymerization rate is much slower than that of the copolymerization of ethylene and hexafluoroacetone. We have data at... 

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