摘要:

Microhardness and optical properties changes induced by gamma-irradiation are studied in vitreous As2S3. The observed 10-25% microhardness increase’ the shift of the absorption edge to long wavelength accompanied with a decrease in its slope (radiation-induced darkening), as well as increasing of impurity bands intensities in the IR vibrational spectra (4000-400 cm−1) are explained by two interconnected processes in vitreous As2S3—defect formation and impurity radiolysis.

ISSN:1042-0150    

DOI:10.1080/10420159508225750

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The Al95Sn5and Al95Sb5melt-spun alloys were prepared by melt spinning technique. The dynamic Mechanical properties of virgin and γ-ray irradiated samples were measured. It was found that the mechanism of producing defects of an ionizing type in a crystal structure is the main factor which causes the difference in the mechanical properties behaviour of the studied alloys.

ISSN:1042-0150    

DOI:10.1080/10420159508225751

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The perovskite phase BaTiO3have been electron irradiated at varying temperatures and beam directions. The dislocation loops produced after room temperature irradiation of BaTiO3have been analyzed and found to lie on the (110) ferroelectric domain boundaries. These loops were of the typeb=l/2[011] (100) andb=l/2[101] (010) and were interstitial in nature. The loops nucleate as square faulted loops which unfault in to round loops. The stacking fault energy was calculated as ∼90 mJm−2. No defect clusters were observed to form at high temperature, though disordering on the atomic scale was believed to occur as, on cooling, ferroelectric domains are disrupted.

ISSN:1042-0150    

DOI:10.1080/10420159508225752

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The temperature dependence of specific heat at constant pressure, Cp(T), has been measured for lithium sodium sulphate, LiNaSo4crystals, at different γ-radiation doses and external bias electric field (Eb), in the temperature range 300-900 K. A nonlinear dependence of transition temperature, T1and a remarkable change in the thermodynamic parameters, were obtained as the effect of both electric field and γ-radiation.

ISSN:1042-0150    

DOI:10.1080/10420159508225753

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Ion mixing efficiency of metals, measured by employing marker experiments at low temperatures (<77 K), varies significantly in magnitude and exhibits different correlations with thermochemical and materials parameters. We have separated the available mixing data into two groups, for noble metals and for other transition metals, respectively, and compared them with phenomenological models formulated based on Vineyard's approach for thermally activated diffusive processes. Two different thermal spike configurations have been considered: well-developed global spikes, and thermal spikes in non-overlapping subcascades. The observed match between model-predicted trends and mixing data suggest that the observed variations in mixing data can be explained in terms of different characters of thermal spike development, i.e., global spikes in noble metals versus non-overlapping spikes in other transition metals. These results are compared with those for ion mixing in bilayers, where different thermal spike mixing behaviours have also been noted. In addition, our estimate of the activation energy for diffusion in thermal spikes is consistent with the notion of a liquid-like diffusion mechanism.

ISSN:1042-0150    

DOI:10.1080/10420159508225754

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The electron paramagnetic resonance of divalent Mn2+ions in K2Cd(SeO4)2.2H2O single crystals has been observed at room temperature using X-band microwave frequency. The Mn2+found to substitute for Cd2+exhibiting a single type of magnetic complexes which have been analyzed using the spin-Hamiltonian appropriate for rhombic symmetry. The forbidden doublets separations in M = +1/2 ↔ −1/2 and M = ±3/2 ↔ +1/2 transitions are obtained and compared with observed doublet separations.

ISSN:1042-0150    

DOI:10.1080/10420159508225755

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The structure and mechanical properties of the melt-spun rapidly solidified Sn1xSbxand Sn Sb8Cu0.5alloys were investigated. The effect of composition as well as gamma irradiation were studied. The Sn Sb, Cu3Sb and Cu6Sn5intermetallic compounds are presented. A low gamma-ray irradiation dose can be used as a useful technique to identify intermetallic compounds crystalline peak.

ISSN:1042-0150    

DOI:10.1080/10420159508225756

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Fast, intermediate and thermal neutrons were investigated inside slabs of poly-vinyl-chloride as a tissue equivalent medium in addition to poly-ethylene by using the activation foil technique. Neutrons are originally emitted from D-T generator with energy 14.5 MeV. The dose equivalent rate as well as the backscattering factors were measured. The presence of chloride atoms within the poly-vinyl-chloride affects its absorption characteristics.

ISSN:1042-0150    

DOI:10.1080/10420159508225757

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The viscoelastic properties of Gamma-ray irradiated polyethylene terephthalate (PET) sheets, extruded in the glassy state, were measured by a method of forced resonance oscillations. Density variations due to γ-irradiation with different doses were found suitable to describe changes of the cross-linking rate. The dynamic Young's modulus of PET-films showed a decrease within the dose range 200-500 kGy which has anomalous behaviour related to the glass transition (alpha-relaxation) by γ-irradiation to a rubberlike state at a dose of 200 kGy. The low frequency velocity of sound showed no correlation with the density of irradiated PET-films.

ISSN:1042-0150    

DOI:10.1080/10420159508225758

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Neutral molecule mass spectrometry (NMMS), secondary ion mass spectrometry (SIMS) in combination with thermal desorption spectroscopy (TDS) study of deuterium trapping in a single crystalline silicon as a result of ion irradiation at fluences 1015-1017cm−2are presented. The subsequent formation of point defects ensembles containing one and two D-atoms (SiD- and SiD2-complexes) was revealed. Accumulation of these complexes starts not in the mean projected range of implanted ions but at the irradiated surface. Their profiles become wider into the bulk with increasing of the fluence

ISSN:1042-0150    

DOI:10.1080/10420159508225759

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor