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A hydrogen-filled ionization chamber used as a target and as a detector of the recoil protons was proposed to be applied for studies of small-angle hadron-proton elastic scattering. The analysis of signals from the chamber electrodes and delay times of the signals made it possible to determine the energy and the emission angle of the recoils, as well as to separate the target volume inside the volume of the chamber. The protons were detected in the energy range 1.0–4.0 MeV, with the energy resolution fwhm = 40 keV. The method can be used in a wide range of incident particle momenta at beam intensities of 104–105 particles/s.

A method is described for measuring short lifetimes of converted γ-transitions fed by α-particle decay. A combination of a β-spectrometer and a microwave cavity is used for timing conversion electrons. The α-particles are timed with another hf cavity which modulates the energy of secondary electrons produced by the α-particles in a foil and accelerated up to 2 keV. The time resolution of the arrangement is about 50 ps. Methods of data analysis are discussed and the results of lifetime measurements of excited states in 219Rn and 207Tl are given.

The decay scheme of Pb 212 β → Bi 212 is analyzed. It is shown that Bi212 has the following levels: 0 keV − 1−, 239 keV − 0−, 300 keV − 1−, 415 keV − 0−. The spin and parity assignments are based on the γ-transition multipolarities and computed log τf values for β-transitions. Configurations which can be ascribed to the levels on basis of the shell model qualitatively explain the γ-transition intensities. The proposed decay scheme implies that the 177 keV transition is an E0-transition; this is compatible with presently available data.

Data on the multiplicity of charged particles and π 0 mesons in π − p and π − n interactions are presented and compared to various models. The average π 0 multiplicity tends to increase with increasing number of charged particles.

1. 1. Four SH groups per mole of enzyme were found in highly purified preparations of tyramine oxidase (monoamine:oxygen oxidoreductase (deaminating), EC 1.4.3.4) from Sarcina lutea. 2. 2. After incubation with o- iodosobenzoate or with catalytic amounts of Cu2+ in aerobic conditions three of the SH groups lost their ability to react with 5,5′-dithiobis (2-nitrobenzoic acid) or with p- chloromercuribenzoate . At the same time the tyramine deaminating activity characteristic of this enzyme markedly decreased and a high lysine deaminating activity appeared. 3. 3. Deamination of lysine by the enzyme that had been treated with Cu2+ was inhibited by carbonyl reagents. The deamination reaction was accompanied by consumption of O2 and formation of H2O2 (about a mole of each per mole of NH3 liberated). 4. 4. Treatment of the modified (oxidized) enzyme with sodium borohydride partially restored the initial content of SH groups, and led to disappearance of the induced lysine deaminating activity and to partial restoration of the initial level of tyramine deaminating activity. 5. 5. Tyramine oxidase treated with Cu2+ also acquired an ability to deaminate putrescine and spermine (but neither histamine nor serotonin). 6. 6. The data obtained accord with previous observations concerning the effects of some oxidizing agents on mitochondria and partially purified preparations of mitochondrial monoamine oxidase from rat liver. According to these observations a decrease in monoamine deaminating activity after treatment with oxidizing agents is accompanied by the appearance of a diamine deaminating activity. In this connection the possibility is discussed of qualitative alteration of catalytic properties of mitochondrial monoamine oxidase accompanied by oxidation of SH groups of the enzyme.

This paper presentd differential cross sections for elastic and inelastic (with excitation of the 4.43 MeV level) scattering of 1 GeV protons from 12 C in the angle range θ cm = 10° − 10°. The measurements were carried out with the energy resolution FWHM = 3.5 MeV.

Yields and energy spectra of H, He, Li, Be, B, C, and O isotopes from 235U neutron fission have been determined. The data are analysed by means of a fast scission model.

Differential cross-sections for pp elastic scattering in the transfer momentum range 2 x 10−3 ⩽ |t| ⩽ x8 10−3 (GeV/c)2 were studied with a hydrogen filled ionization chamber which was used as a target and as a detector of the recoiled protons. The measurements have been done at Plab. = 1.11 GeV/c, 1.28 GeV/c, 1.34 GeV/c, 1.40 GeV/c and 1.70 GeV/c. The real part of the spin independent forward scattering amplitude has been determined, the results being in agreement with the dispersion relation calculations.