A new reagent for activating carboxyl groups: diphenyl 2-oxo-3-oxazolinylphosphonate

Diphenyl 2-oxo-3-oxazolinylphosphonate serves as a carboxyl-activating reagent to permit a direct preparation of versatile intermediate, 3-acyl-2-oxazolones or a one-step formation of amides from carboxylic acids.     

Asymptotic joint distribution of the largest roots of several multivariate F matrices I. Quasi-independent case

An asymptotic expansion of the joint distribution of k largest characteristic roots C_M⁽ⁱ⁾(S_iS₀^?1), i = 1,…, k, is given, where S'_is and S₀ are independent Wishart matrices with common covariance matrix Σ. The modified second-approximation procedure to the upper percentage points of the maximum of C_M⁽ⁱ⁾(S_iS₀^?1), i = 1,…, k, is also considered. The evaluation of the expansion is based on the idea for studentization due to Welch and James with the use of differential operators and of the perturbation procedure.     

Pyrolysis—gas chromatography of methyl methacrylate—styrene and methyl methacrylate—α-methylstyrene copolymers

The pyrolysis—gas chromatographic behaviour of methyl methacrylate copolymers with styrene or α-methylstyrene was investigated with a Curie-point pyrolyzer. Monomer yield from each copolymer was very high as a result of the high probability of unzipping. Though only small quantities of dimers and or trimers are formed on the pyrolysis of two copolymers, they reflect the sequence distribution of copolymers. Under some assumption, the run number of each copolymer is calculated using the amounts of dimer and or trimer formed.     

New weak phenomena and modified left-handed currents

It is shown that left-handed weak doublets with mixed states of charmed and ordinary quarks are important for overall explantions of recent weak phenomena, especially, ξ_vis distribution in dilepton production.     

Determination of effective-charge distribution on some deuterobenzenes from their out-of-plane gas-band intensities

Infrared band intensities of the out-of-plane fundamental vibrations were measured for benzene and its deuterium derivatives in the gas phase by using the Wilson-Wells method. The 41 intensity values obtained were successfully interpreted in terms of only one parameter, the effective charge on the hydrogen atom of benzene: ?₀(H) = 0.125 ± 0.001 e. This value was consistent with the results given by the quadrupole-moment measurements and by the MO calculations. The effective charge in the gas phase was also compared with that in the solution state.