Characterization of carbide phases in high speed tool steels

A study is reported on carbides electrolytically extracted from two different types of high speed tool steels as quenched and after tempering. According to X-ray diffraction analysis and EDS microanalysis, Mössbauer spectra show the presence of MC and M₆C in every analysed sample. Only a few substitutional Fe atoms should be present in MC and they give a minor contribution to the Mössbauer spectrum. A model for evaluating the Mössbauer spectrum of M₆C is proposed which is based on the symmetry of lattice sites occupied by Fe atoms and partially substituted by other metallic atoms. The proposed model also allows to get information on the amount of this substitution.     

Charm production in two-photon collisions: Calculation of the leading nonperturbative contribution in QCD

The leading nonperturbative contribution to the cross section of charm production in two-photon collisions is calculated in QCD. Operator expansion is used and the c-quark interaction with vacuum gluon condensate is taken into account. As a result, the moments of the charm contribution to the photon structure function are obtained. The moments with sufficiently high numbers turn out to be sensitive to the gluon condensate.     

Deformations of incompressible bodies with free boundaries

Communicated by C. Dafermos     

Scattering of scalar fields by rough surfaces. Accounting for multiple scattered waves

Physical Engineering Institute, Moscow. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 34, No. 5, pp. 565–574, May, 1991.     

Validation of a solid-phase extraction high-performance liquid chromatographic assay for doxazosin.

The determination of doxazosin by high-performance liquid chromatography with fluorescence detection is described. Propanolol was used as the internal standard. Plasma samples were treated with methanol to precipitate the proteins. Doxazosin was isolated with C18 reversed-phase extraction columns. The determination limit is 1 ng/ml of plasma, while the extraction columns can be reused frequently. The method is applied to clinical trial samples.     

Copper-D-penicillamine complex as potential contrast agent for MRI.

In vitro and in vivo proton T1 data are reported that demonstrate that the paramagnetic copper-D-penicillamine complex can be applied as a potential contrast agent to magnetic resonance imaging.     

Electron Energy Distribution Functions in CO2 Laser Mixture: The Effects of Second Kind Collisions from Metastable Electronic States

Electron energy distribution functions (eedf) in CO₂ laser discharge (He—CO₂—N₂—CO mixture) have been calculated by solving the Boltzmann equation in the presence of given concentrations of excited (vibrational and electronic) states. The results show a well structured eedf as a result of second kind collisions coming from metastable electronic states of N₂ and He as well as a strong dependence of rate coefficients for CO₂ dissociation and for the ionization of the different species.     

The experimental structure of199Au and the interacting boson-fermion model

Gamma rays of¹⁹⁹Au obtained after double neutron capture in¹⁹⁷Au were measured at the ILL high flux reactor. A level scheme up to 1770 keV excitation energy is established. The result is compared with IBFM and Boson-Fermion-Symmetry calculations.     

Parity violation at neutron p-wave resonances of238U and232Th and related questions

Parity violation effects have been studied at 40 neutron p-wave resonances of the even-even nuclei²³⁸U and²³²Th. Of these 11 show parity violation effects larger than 2 standard deviations, making parity violation a rather common phenomenon. Parity mixing up to 10% has been found. The root-mean squared matrix elements for parity violation derived from these resonances are M=0.58 (+0.50/-0.25) meV for²³⁸U, respectively 1.39 (+0.35/-0.38) meV for²³²Th.     

Correlation between gravitational-wave detectors and particle detectors during SN1987A

Summary A review of the correlations between gravitational-wave detectors and particle detectors during SN1987A is given. The correlation between the Maryland and Rome g.w. detectors with the Mont Blanc neutrino detector is illustrated. This correlation extends during a period of one or two hours centred at 2∶45 UT of 23 February 1987, with the ?neutrino? signals delayed by (1.1±0.5) s and with a probability of the order of 10⁻⁵ to be accidental. Using the data obtained with the Kamiokande and IMB detectors, with the same statistical choices and procedures for the data analysis used previously, the above result is confirmed with a probability of the order of 10⁻³ or 10⁻⁴ that the additional correlation be accidental. Paper presented at the V Cosmic Physics National Conference, S. Miniato, November 27–30, 1990.