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381.
We show how a vortex structure manifests itself in the one-dimensional projection of a vortex field. We calculate the extent of spatial coherence and entropy of such projections. We quantify the spatial coherence and discuss the properties of the Wigner functions for the projected field. 相似文献
382.
A new method for the construction of quaternary centers on cycloalkane rings is reported. The Cope rearrangement of 4-methyl-2-allyl-2-(N-pyrrolidinyl)-carboxamide-3-cyclohexenone yields 4-methyl-4-allyl-2-(N-pyrrolidinyl)-carboxamide-2-cyclohexenone in high yield. The rearrangement substrates are easily generated from Birch reduction-allylation of o-anisic acid derivatives. 相似文献
383.
J. N. Mathur M. S. Murali M. V. Balarama Krishna R. H. Iyer R. R. Chitnis P. K. Wattal A. K. Bauri A. Banerji 《Journal of Radioanalytical and Nuclear Chemistry》1996,213(6):419-429
The partitioning and recovery of237Np from three types of simulated high level waste solutions originating from PUREX processing of spent nuclear fuels such as sulfate bearing high level waste (SB-HLW), HLW from a pressurised heavy water reactor (PHWR-HLW) and from a fast breeder reactor (FBR-HLW) have been carried out using a mixture of 0.2M CMPO and 1.2M TBP in dodecane. Quantitative extraction of neptunium was possible by either oxidizing it to the hexavalent state keeping K2Cr2O7 at 0.01M concentration or by reducing it to tetravalent state keeping Fe2+ at 0.02M concentration. Stripping of neptunium was carried out using different reagents, such as dilute nitric acid, oxalic acid and sodium carbonate. Almost quantitative recovery of neptunium has been achieved during these studies. 相似文献
384.
385.
Kinetics of oxidation of six aliphatic aldehydes by Os(VIII) in alkaline solutions have been studied. The reaction is of first order with respect to each of the aldehyde and Os(VIII). The pseudo-first order rate constants decreased with an increase in the concentration of hydroxyl ions. The oxidation of deuterioacetaldehyde (MeCDO) exhibited a substantial primary kinetic isotope effect. Separate rate constants for the oxidation of hydrate and free aldehyde forms have been evaluated. The aldehyde hydrate is postulated as the active reductant. Ionic strength has no noticable effect on the rate. The rate-determining step is, therefore, postulated to be a bimolecular reaction between the aldehyde hydrate and [OsO4(OH)2]?2. The value of the limiting rate constant exhibited an excellent correlation with Taft σ* values; reaction constant being negative. A mechanism involving transfer of a hydride ion from the aldehyde hydrate to Os(VIII) has been proposed. 相似文献
386.
We consider the possibility that the dark energy responsible for inflation is deposited into extra dimensions outside of our observable Universe. Reheating and all matter can then be obtained from the minimal supersymmetric standard model flat direction condensate involving the Higgs bosons Hu and Hd, which acquires large amplitude by virtue of quantum fluctuations during inflation. The reheat temperature is TRH < or = 10(9) GeV so that there is no gravitino problem. We find a spectral index ns 1 with a very weak dependence on the Higgs potential. 相似文献
387.
388.
389.
Adiabatic density perturbations and matter generation from the minimal supersymmetric standard model
We propose that the inflaton is coupled to ordinary matter only gravitationally and that it decays into a completely hidden sector. In this scenario both baryonic and dark matter originate from the decay of a flat direction of the minimal supersymmetric standard model, which is shown to generate the desired adiabatic perturbation spectrum via the curvaton mechanism. The requirement that the energy density along the flat direction dominates over the inflaton decay products fixes the flat direction almost uniquely. The present residual energy density in the hidden sector is typically shown to be small. 相似文献
390.
Summary An improved microcombustion technique is described for nitrogen estimation in heterocyclic compounds by use of a modified Dumas filling.
Communication No. 1663 from the Central Drug Research Institute, Lucknow, India. 相似文献
Zusammenfassung Eine verbesserte Mikroverbrennungstechnik für Stickstoffbestimmungen in heterocyklischen Verbindungen unter Verwendung einer modifizierten Dumas-Füllung wurde beschrieben.
Communication No. 1663 from the Central Drug Research Institute, Lucknow, India. 相似文献