Simultaneous insertions

Other mechanistic possibilities also exist for the [5-1-2] cycloaddition reaction and cannot be mled out at this point In addition to the stepwise pathways depicted in Scheme 13.8, it is also possible that coordination of the 27r-component to 42 could lead directly to 48 through simultaneous insertion and cleavage. Variations on these events, such as direct insertion into the cyclopropane to form a metaUacyclobutane, are also possible. 

The next correction of order a Za.)EF is generated by the gauge invariant set of diagrams in Fig. 9.8(c). The respective analytic expression is obtained from the skeleton integral by simultaneous insertion in the integrand of the one-loop polarization function Ii k) and of the electron factor F k). 

Fig. 10.15. Graphs with simultaneous insertions of the electron and muon loops...

The simultaneous insertion of an alkene bond and a carboxyl function into a sugar molecule is very attractive for carbohydrate chemistry in view of the further useful derivatization possible. This problem has been successfully solved by employment of the Wittig reaction, as well as its phosphonate modification (see p. 259). The compounds thus far synthesized are not numerous, although their transformations have been studied in detail and have resulted in a new method for the carbon-chain extension of carbohydrates.26... 

Propagation on coordination centres is formulated as simultaneous insertion with the breaking of a covalent bond (alcoholate) [315, 318] (Mt is the metal atom)... 

Likewise, Komorsky-Lovric et al. investigated the behavior of lutetium bisphtha-locyanine with the voltammetry of microparticles [108]. This solid-state reaction (which may be studied with either square-wave or cyclic voltammetry) was shown to proceed via the simultaneous insertion/expulsion of anion ions. The oxidation was found to have quasi-reversible characteristics in electrolyte solutions containing perchlorate, nitrate, and chloride, whereas bromide and thiocyanate... 

Simultaneously insert the swabs into the appropriate ends of the tube, pushing them far enough so that wrapped tape handles seal the ends of the tube as shown here. 

Nested injection involves the insertion of a sampling loop into a second loop which is simultaneously inserted into the main channel of the flow... 

The sample and the reagent solutions are simultaneously inserted into convergent carrier streams, and merging of the established zones occurs at the point where the streams converge. 

In the electrochemical sense the p-type doping reaction consists of anodic oxidation of neutral polymer chains to polycations with simultaneous insertion, to the polymer matrix, of electrolyte originating anions which preserve the electrical neutrality of the system. By symmetry, n-type doping is achieved by cathodic reduction of the polymer chains to polyanions, with... 

What proved a triumph for Mitchell s hypothesis was the experiments involving simultaneous insertion of ATP synthtases and of one of the primary pumps.163 The synthesis of ATP was accomplished on liposomes. Addition of substances increasing the conductance of the membrane disturbed the coupling both in liposomes and in mitochondria. 

Preferred shim rods are. also inserted automatically by regulating-rod limit switches., If. the regulating rod is. withdrawn less than 7 in. (,R9)., preferred rods are inserted, and,. if the withdrawal, is less.than 5 in. (RIO), all rods are inserted. This simultaneous insertion of. all rods is called "reverse." It may at,all times.be initiated manually on S-1 or.by a level of 20iX. above Nf, Reverse, may also. be. caused by. certain period or level signals. If, the run auxiliary r,elay, R-3,.-is not picked-up, a., level greater than... 

A second type of electroactive polymer film is the redox polymer which contains localized sites that may be oxidized and reduced. Charge is not distributed along the polymer chain but is localized at specific, pendant redox sites. An example of this type of polymer is poly(vinylferrocene) (PVF) which is shown in Figure 2.1 in both the reduced and oxidized forms. Poly(vinylferrocene) undergoes a reversible redox reaction when used with an appropriate electrolyte (such as LiC104 in acetonitrile) and has been used as a model redox polymer system [17-19]. The oxidation process occurs by removal of electrons and the simultaneous insertion of anions from the electrolyte. The Fe centre in the pendant ferrocene group undergoes oxidation. 

The oxidation or doping process of electroactive polymers involves the simultaneous insertion of charge and a counterion to balance the charge. For redox polymers such as polyvinylferrocene the process may be written... 

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