G. P.C, analysis

G.P.C. analysis it was concluded the polymer fraction eluting at 27 ml. was a coupled dimer or two-arm star. The DVB/RLi ratio in this case was 3.0 (corrected for 44% EVB). From this observation it became of interest to study the influence of DVB/RLi ratio on the efficiency of star formation. The reaction time, temperature, and arm molecular weight were held constant while the DVB/RLi ratio varied. 

Figure 7 illustrates the influence of the increase in the DVB/RLi ratio as well as reaction time for polybutadienyllithium anions. The efficiency is plotted as the ratio of linked to unlinked chains. At the very high ratios (11.9-12.9) nearly quantitative linking is observed as seen from the G.P.C. analysis in Figure 8. However, the moelcular weight distribution is broadened at the higher ratios, possibly indicating intermolecular or inter-nodule star coupling between two different star macromolecules. As mentioned previously, Reaction 5 would be more likely to occur at the higher ratios thus the overlap of the...

G.P.C. analysis was carried out for a series of pyrolytic oils obtained in a batch reactor operated at various temperatures similar to the P.D.U. hearth temperatures (JJ.) and the results showed a rather similar weight average molecular weight which indicate a fair selective separation of wood oil constituents at various temperatures in the P.D.U. 

To a solution of 4-t-butylcyclohexanone (lmmol), tris(triphenylphos-phine)ruthenium(n) chloride (0.05 mmol) and silver trifluoroacetate (0.05 mmol) in toluene (5 ml) was added triethylsilane (1.5 mmol). The mixture was heated under reflux for 20 h, and concentrated under reduced pressure. The residue was diluted with hexane (3 ml), filtered and distilled to give a mixture of triethylsilyl ethers (0.96mmol, 96%), b.p. 70°CI 0.1 mmHg. G.l.c. analysis shows an axial (cis) equatorial (trans) ratio of 5 95—a result comparable to the best LAH results. 

Fig. 9. Pulse microreactor system for use with 13C-labeled hydrocarbons. D, E, and J are microreactors J contains the catalyst to be used for hydrocarbon skeletal reaction D and E are used, when necessary, to generate the required reactant hydrocarbon from a non-hydrocarbon precursor (e.g., alcohol dehydration in D and olefin hydrogenation in E) reactant injected at C. F is a trap which allows the accumulation of products from several reaction pulses before analysis G is a G.P.C. column, K a katharometer. Traps H collect fractions separated on G for subsequent mass spectrometric study. When generating reactant hydrocarbon in D and E, a two-step process is preferable in which, with J below reaction temperature, the purified reactant hydrocarbon is collected in H, and this is recycled as reactant with D and E below reaction temperature but with J at reaction temperature. After C. Corolleur, S. Corolleur, and F. G. Gault, J. Catal. 24, 385 (1972).

In a 100-ml round-bottomed flask place 16.1 g (O.lOmol) of 3-bromocyclo-hexene (Expt 5.68), 38.7 g of dried, redistilled quinoline and a magnetic stirrer follower. Attach to the flask a Claisen still-head fitted with a thermometer and a condenser set for downward distillation. Protect the apparatus from atmospheric moisture by a calcium chloride guard-tube attached to the side-arm of the receiver. Support the reaction flask in an oil bath which rests on a magnetic stirrer/hotplate, commence stirring rapidly and heat the oil bath to 160-170 °C. The cyclohexadiene steadily distils as colourless liquid, b.p. 80-82 °C, over a period of about 30 minutes, yield 5.4 g (68%). The product is 99 per cent pure by g.l.c. analysis use either a 2.7 m column of 10 per cent polyethyleneglycol adipate on Chromosorb W held at 60 °C with a flow rate of carrier gas of 40ml/minute, tR 2.4 minutes, or, a 1.5 m column of 10 per cent Silicone oil on Chromosorb W held at 6 °C with a flow rate of carrier gas of 40ml/minute, tR 1.5 minutes. 

Method B. The toluene-p-sulphonylhydrazone of acetophenone (0.721 g, 2.5 mmol) (1), m.p. 140—141.5 °C, is placed in a flame-dried, nitrogen-filled flask containing 5 ml of chloroform. Catecholborane (0.52 ml, 5.0 mmol) (Section 4.2.7, p. 420) is added and the reduction allowed to proceed for 2 hours at room temperature (2). Methanol (1 ml) is added to destroy the excess of hydride followed by the addition of tetrabutylammonium acetate (0.7 g, 2.5 mmol). The reaction mixture is stirred for 4 hours when g.l.c. analysis indicates a 94 per cent yield of ethylbenzene. The product is isolated by distillation, yield 0.21 g (79%), b.p. 132-136 °C. 

The products from these hydrogenations were separated into gases (analyzed by G.C.), water (analysed by azeotropic distillation), insolubles (CH2CI2 insolubles), asphaltene (CH2CI2 soluble/X4 insoluble) (Shell X4 40-60 C b.p. light petroleum), oils (CH2CI2 soluble/X4 soluble). Hydrogen transferred from the donor solvent was determined by G.L.C. analysis of the ratio of tetralin to naphthalene in the total hydrocarbon liquid product. 

Until such theories can be developed, laboratory experiments can be performed to determine chemical effects in aquatic colloid chemical processes for actual situations. This is suggested by the analysis presented in this chapter of the aquifer study by Harvey et al. (1989) and is illustrated for Lake Zurich by the study of Weilenmann et al. (1989). Since mass transport can be described with some success [e.g., p, c),heor and 2(r,y )slhcor], this knowledge can be combined with laboratory determinations of attachment probabilities such as those illustrated in Table 2 for a(p, c)exp and listed in Table 5 for ci(i,j)s exp to describe the kinetics of deposition and aggregation (e.g., Eqs. 5 and 6) in aquatic systems. 

---