The reaction of heterofunctional condensation of hydroxymethyl(phenyl)cyclosiloxanes with tetrachlorosilane in the ratio 2:1 of initial products has been studied in the presence of pyridine and ...bis(heptamethylcyclotetrasiloxy)dichlorosilane and bis(pentaphenylcy-clotrisiloxy)dichlorosilane were obtained. The reaction of heterofunctional condensation of bis(organocyclosiloxy)dichlorosilanes with αω-dihydroxydimethylsiloxanes in the presence of pyridine was investigated. It was shown that at small lenghts of the linear dimethylsiloxane links, the reaction of heterofunctional condensation runs both intermolecularly with formation of polymers and intramolecularly with formation of tricycloorganosiloxanes. It was established, that the insertion of bis organocyclosiloxy fragments in the side chain hinders the chain transfer reactions that proceed with release of the D-type cycles during thermal depolymerization. Thermogravimetric, thermo-mechanical and X-ray studies of synthesized copolymers were carried out.
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We present the final combination of CDF and D0 measurements of cross sections for single-top-quark production in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. The data ...correspond to total integrated luminosities of up to 9.7 fb$^{−1}$ per experiment. The t-channel cross section is measured to be σ$_t$=2.25$_{-0.31}^{+0.29}$ pb. We also present the combinations of the two-dimensional measurements of the s- vs t-channel cross section. In addition, we give the combination of the s+t channel cross section measurement resulting in σ$_{s+t}$=3.30$_{-0.40}^{+0.52}$ pb, without assuming the standard model value for the ratio σ$_s$/σ$_t$. The resulting value of the magnitude of the top-to-bottom quark coupling is |V$_{tb}$|=1.02$_{-0.05}^{+0.06}$, corresponding to |V$_{tb}$|>0.92 at the 95% C.L.
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