摘要:

Irradiation of substituted uracil derivatives with ultraviolet light causes changes in the infrared spectrum possibly associated with the formation of loosely associated species. Results are given for uracil, thymine, 5-iodouracil, 5-bromouracil, 1-ethyluracil, 5-mercaptouracil and 1-cyclohexyluracil. The latter three compounds do not exhibit evidence of new bond formation while the others show changes in band intensity and the appearance of new bands.

ISSN:0033-7579    

DOI:10.1080/00337577808238810

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The increase of the effective concentration of interstitial traps with increasing Frenkel defect concentration has been investigated in pure Al samples irradiated at 55 K with 1 MeV and 3 MeV electrons. The increase of the trap concentration per Frenkel defect produced was found to be larger for the 3 MeV than for the 1 MeV irradiation. The difference is ascribed to di-interstitial formation within the small cascades produced by 3 MeV electron irradiation. For the cascades containing two to five Frenkel defects it was found that in the average about 12% of the interstitials produced within these cascades encounter upon migration and form di-interstitials.

ISSN:0033-7579    

DOI:10.1080/00337577808238811

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Terrestrial feldspars (orthoclase, anorthite, bytownite, labradorite, oligoclase, and albite) have been irradiated with252Cf-fission products as well as Kr and Xe ions of different energies in order to study track length and track diameter as a function of crystal orientation. Both track length and track diameter of heavy particle tracks in orthoclase depend on the angle of incidence as well as on the angle of azimuth with respect to a fixed direction in the crystal surface plane. As to the plagioclase feldspars, only the track diameters appear to vary with crystal orientation. The different bulk and track etch rates for the main cleavage planes {001} and {010} are given. Within the plagioclase group the track registration properties were found to vary distinctly with the Ca content. Possible explanations for this observation are discussed.

ISSN:0033-7579    

DOI:10.1080/00337577808238812

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

A new experimental approach for elucidating non-radical processes in radiation chemistry is described. The method consists essentially of determining the influence of an additive, which interferes with reactions of ions or excited molecules in the system studied, on the (apparent) cross-combination ratio of certain radicals. The main advantages of the method (with respect to the conventional radical scavenging technique) are that the existence of a non-radical process may be elucidated at very low concentrations of additive, that selectivity of the additive is much less critical and that information on the nature of the non-radical process is available from the type of scavenger used. The method is illustrated with an investigation on the modes of formation of chlorohexanes, in the radiolysis of 1-chloropropane.

ISSN:0033-7579    

DOI:10.1080/00337577808238813

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The Snoek peak of internal friction of the Fe-0.21wt%-0.2wt%Cu alloy neutron-irradiated at 330–341°C, was measured to detect the resolution of carbon atoms. The resolution temperature of carbon atoms in the neutron-irradiated alloy is about 400°C, but that in the unirradiated alloy is about 200°C. The sources of the resolution of carbon atoms are considered cementite and irradiation defects which trap carbon atoms in the irradiated alloy, but in the unirradiated alloy, interstitial carbon atoms come from cementite. Copper in α-iron delays the resolution of carbon atoms.

ISSN:0033-7579    

DOI:10.1080/00337577808238814

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The effect of 14 MeV neutron bombardment on the electrical resistance of 500 Å thick vacuum-coated Al film is investigated. In the beginning, a slow, then sharp and finally again slow increase is observed in the electrical resistance of the film. Transmission electron micrographs of the film after the same dose of neutron irradiation show a large number of defects produced in the film due to neutron irradiation, which seems to be the cause of this increase.

ISSN:0033-7579    

DOI:10.1080/00337577808238815

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The angular distributions of the sputtered gold atoms near the ⟨110⟩ crystallographic directions are analyzed by means of an autoradiography. For a number of directions it is found a difference between the angular half-width of the spots measured along the {100} and {110} plane traces.

ISSN:0033-7579    

DOI:10.1080/00337577808238816

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

It is well known that no trapped electron center exists stably in irradiated silver chlorides even at low temperatures. On the other hand, the irradiation of the ultra-violet light at room temperature produces the broad absorption on the long wavelength side of the fundamental absorption, which has been assigned to so-called colloid bands by Brown and Wainfan.1Such a broad band has been observed also in AgN3,2TIN33and Pb(N3)2.3

ISSN:0033-7579    

DOI:10.1080/00337577808238817

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Theoretical1,2as well as experimental observations3suggest that irradiation may alter the volume fraction of precipitate present in a two-phase alloy. Particularly appropriate to the present work, Korenko3has irradiated an Ni-7.1 wt.% Al alloy at temperatures between 450 and 750°C using 1.0-MeV electrons in the high-voltage electron microscope (HVEM). Irradiation to doses of ∼7 displacements per atom (dpa) and temperatures near 600°C reportedly revealed drastic increases in the volume fraction of γ′, i.e., from 10 to 100% (pure γ′). The present results are consistent with Korenko's experimental observations except that the volume fraction of γ′ in the foil is not significantly altered by irradiation.

ISSN:0033-7579    

DOI:10.1080/00337577808238818

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

THEORETICAL SOLID STATE PHYSICS, by W. Jones and N. H. March, John Wiley and Sons Ltd., New York 1973. (Volumes 1 and 2 £16.25 each)

ISSN:0033-7579    

DOI:10.1080/00337577808238819

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor