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91.
92.
Srinivas Kantevari C. K. Snehalatha Nair M. Pardhasaradhi 《Journal of heterocyclic chemistry》2006,43(5):1353-1356
Practical synthesis of 5‐(4′‐methylbiphenyl‐2‐yl)‐1H‐tetrazole, key intermediate in several angiotensin II receptor antagonists from 2‐fluorobenzonitrile in excellent yields and very high purity is described. 相似文献
93.
M D Srinivas 《Pramana》1982,19(2):159-173
This paper is devoted to a study of some of the basic conditions which have to be satisfied by a hidden variable theory in
order that it can reproduce the quantum mechanical probabilities. Of course one such condition, which emerges from the important
theorem of Bell, is that a hidden variable theory has to be non-local. It is shown that a hidden variable theory is also incompatible
with the conventional interpretation of mixed states and the mixing operation in quantum theory. It is therefore concluded
that, apart from being non-local, a hidden variable theory would also necessarily violate the usual assumption of quantum
theory that the density operator provides an adequate characterization of any ensemble of systems, pure or mixed. 相似文献
94.
Carbon–hydrogen bond dissociation enthalpies (BDEs) were computed for all haloethenes, C2H4−nXn (n=0–3, X=F, Cl, Br, I), at the B3LYP/6-311+G(3df,2p) level using isodesmic reactions. It was found that C–H bond strengths in the monohaloethenes varied substantially, by as much as 18 kJ mol−1, dependent upon the bond's stereochemical position relative to the halogen. BDEs in the dihaloethanes varied in the order CX2CH–H>(E)-CHXCX–H>(Z)-CHXCX–H. Trends in the computed bond enthalpies were discussed and explained on the basis of relative steric repulsions and hyperconjugative delocalization interactions, as determined from Natural Bond Orbital analysis. 相似文献
95.
We demonstrate that a flowing liquid jet can be controllably split into two separate subfilaments through the application of a sufficiently strong tangential stress to the surface of the jet. In contrast, normal stresses can never split a liquid jet. We apply these results to observations of uncontrolled splitting of jets in electric fields. The experimental realization of controllable jet splitting would provide an entirely novel route for producing small polymeric fibers. 相似文献
96.
97.
98.
We present measurements of Eulerian longitudinal velocity autocorrelations in homogeneous, isotropic, high-intensity (~9%) free-stream turbulence behind an active grid. Spatial correlations are measured using particle image velocimetry as well as with two-point hot-wire anemometry (HWA), while temporal correlations are measured using HWA. The temporal correlations are transformed into spatial correlations by using Taylor's ‘frozen’ hypothesis with both the mean as well as instantaneous velocities. A model relating Eulerian spatial and temporal autocorrelations is also used for this purpose. The differences from the measured spatial correlation resulting from the use of Taylor's hypothesis on the temporal correlation is quantified; even at this moderately high level of turbulent intensity, the result from the use of the instantaneous velocity as convection velocity is practically indistinguishable from that obtained using the mean velocity. Use of the model produces a good agreement between the estimates of the spatial correlation function. A relation between Eulerian spatial and temporal integral scales is also derived. 相似文献
99.
100.