Deuterated nitrobenzene

Equation (5) was examined by Scott and Reese [1] employing mixtures of nitrobenzene and fully deuterated nitrobenzene as the test sample. Their retention times were 8.927 min. and 9.061 min., respectively, giving a difference of 8.04 seconds. The separation ratio of the two solutes was 1.023 and the efficiencies of the front and rear portions of the peaks were 5908 and 3670 theoretical plates, respectively. The detector was, not surprisingly, found to have the same response to both solutes, i.e., a = (3. Thus, inserting these values in equation (5),... 

The retention times of a series of mixtures of nitrobenzene and deuterated nitrobenzene were then actually measured and are included as points in Figure 7. It is seen that close agreement is obtained between the experimental points and the... 

Equation (19) was examined by Scott and Reese (i5) employing mixtures of nitrobenzene and fully deuterated nitrobenzene as the test sample. Their retention times were 8.927 min and 9.06i min respectively giving a difference of 8.04 seconds. The separation ratio of the two solutes was... 

The retention time of a series of mixtures of nitrobenzene and deuterated nitrobenzene were determined by Scott and Reese and are shown plotted as points in figure (7). It is seen that close agreement is obtained between the experimental points and the theoretical curve. The procedure described is an interesting alternative for the analysis of mixtures of closely eluted solutes, to the difficult and tedious construction of columns of extremely high efficiencies. With great care and the use of modern sophisticated computer programs the required accuracy can be easily obtained, and it is suprising that this approach is not used more often. 

In our recent study [59], we have utilized NMR spectroscopy at 400 MHz to study the selective hydration phenomena for typical univalent anions (X = Cl , Br , I , NO, CIO4, and SCN ) in deuterated nitrobenzene (NB-ds). For the respective anions, dependences of the chemical shift of water on water and ion concentrations have been examined. We have found that the selective hydration of these anions can be explained in terms of the successive reaction mechanim [e.g., Br Br (H20) Br (H20)2 Br (H20)3 Br (H20)4]. In addition, measurements of spin-lattice relaxation times have shown that the rate of rotational diffusion of water molecules is considerably slowed by the hydration of the ions. The results are summarized below. 

Mechanistic studies with deuterated nitrobenzene suggest that the readion involves the carbamoyl complex [PhNCO(Pd)] 1057, although it is not clear as to how important this pathway is [769-771]. 

The change in stoichiometry depending on the experimental conditions is not limited to this catalytic system. An identical problem is found in another system, still based on palladium, but without any other metal-containing cocatalyst. In this last case, the same type of competing stoichiometries has been found and confirmed by the use of deuterated nitrobenzene (see paragraph 6.3.3). 

Before investigating the properties of the doped polymer solutions, a good knowledge of the chain statistics in the neutral state in solution is needed. SANS experiments were first performed on poly-butylthiophene in deuterated nitrobenzene (16), then in deuterated THF(17). Two types of samples were used, one with Mw = 49000 and a weight distribution = 1-5 used for die neutral solutions in nitrobenzene, and... 

The kinetic isotopic effects observed in labeled / -deuterated nitrobenzene decrease with increasing base concentration. As an example KIE values from 4.2 ([base] < O.lmol/L) to 0.8 ([base] in the range 0.1-0.6 mol/L) have been obtained. 

We assumed that poly-BFl-AP is terminated at both chain ends. The phenyl group of the anionic initiator was believed to be fixed, whereas a relatively acidic proton linked to the indenyl moiety is present at the other end. If the propagation/ depropagation reaction requires the presence of a negative charge in the terminal indenyl moiety, the reaction kinetics will depend on the concentration of the depro-tonated chains and ultimately on the acid-base equilibrium. In deuterated nitrobenzene, the depolymerization rate is negligible at room temperature probably because... 

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