作者：
HAQUE, ADIXON, AEBRODIE, DEUniv of Waterloo
Guelph-Waterloo Program for Graduate Work in Physics Waterloo Ont Can Univ of Waterloo Guelph-Waterloo Program for Graduate Work in Physics Waterloo Ont Can
The use of electron-beam irradiation combined with a hot-wall technique during deposition of CdS films is described. CdS films 2–10 μm thick were thermally deposited with and without electron bombardment on glass su...
详细信息
The use of electron-beam irradiation combined with a hot-wall technique during deposition of CdS films is described. CdS films 2–10 μm thick were thermally deposited with and without electron bombardment on glass substrates using a hot-wall technique under a pressure greater than 1 × 10−6] Torr (1 Torr = 133.3 Pa). Film properties were studied using low-angle X-ray diffraction, scanning electron microscopy, optical microscopy using a chemical decoration technique, Hall-effect measurements, and temperature-dependent dark conductivity. The surface grain size varied from 2 to 5 μm and films were brownish orange with a smoky appearance.
Electronic insulating solids are divided into 4 distinct categories on the basis of their different positron-transport properties. Of the 8 types of material tested, 5 were positronic as well as electronic insulators ...
详细信息
Electronic insulating solids are divided into 4 distinct categories on the basis of their different positron-transport properties. Of the 8 types of material tested, 5 were positronic as well as electronic insulators but positron mobilities ranged up to 102 cm 2 /v.s. - in paraffin wax. Striking qualitative differences in the fraction of positronium decays, and its dependence on electric field strength, supplement the mobility data in defining the different categories.
作者：
JERZAK, SFUJIMOTO, MUiv of Guelph
Guelph-Waterloo Program for Graduate Work in Physics Guelph Ont Can Uiv of Guelph Guelph-Waterloo Program for Graduate Work in Physics Guelph Ont Can
A comparative EPR study with various paramagnetic probes of iron-group elements has been carried out on the ferroelectric phase transition in tris-sarcosine calcium chloride (TSCC) crystals. These ions have yielded co...
详细信息
A comparative EPR study with various paramagnetic probes of iron-group elements has been carried out on the ferroelectric phase transition in tris-sarcosine calcium chloride (TSCC) crystals. These ions have yielded complementary results, and one probe was found to be insufficient to obtain necessary information about the transition mechanism. While the soft-mode vector is inferred from the VO++] spectra, either Cr+++] or Fe+++] ions are best suited to observe the critical phenomena near the transition temperature (Tc ~ 130 K). A critical broadening above Tc and an asymmetrical splitting below Tc are observed in the Cr+++] and Fe+++] spectra. The Mn++] spectra are unique in that the order–parameter fluctuation appears only slightly in the line widths above Tc, while the critical region below Tc is characterized by the coexistence of para- and ferroelectric phases. The critical slowing-down effect in the EPR line widths is found to be consistent with that observed in dielectric measurements, suggesting that sarcosine dipoles in TSCC crystals are associated with the elementary dipole for spontaneous polarization.
作者：
BOSE, SKPOLL, JDUniv of Guelph Campus
Guelph-Waterloo Program for Graduate Work in Physics Guelph Ont Can Univ of Guelph Campus Guelph-Waterloo Program for Graduate Work in Physics Guelph Ont Can
A broad absorption in the spectral region 4000–7500 cm−1] has been observed in tritiated as well as proton-irradiated samples of solid deuterium. To explain this absorption we investigate two different types of local...
详细信息
A broad absorption in the spectral region 4000–7500 cm−1] has been observed in tritiated as well as proton-irradiated samples of solid deuterium. To explain this absorption we investigate two different types of localized electronic states in the solid. It is shown that the absorption can be interpreted as being due to the lowest energy bound-state transitions of electrons localized in nonspherical cavities of two different average radii. The localization is assumed to be initiated by vacancies. The shape of the absorption line is calculated by estimating the cavity size and the frequency of the breathing-mode oscillation of these cavities.
The first results of the analysis of bitumen and oil sands using the recently developed n.m.r. spingrouping technique are presented. The n.m.r. relaxation experiments were carried out on bitumen, and on natural and dr...
详细信息
The first results of the analysis of bitumen and oil sands using the recently developed n.m.r. spingrouping technique are presented. The n.m.r. relaxation experiments were carried out on bitumen, and on natural and dried oil sands samples. The results indicate that the spin-grouping can resolve and quantify several components of the samples studied. The bitumen and bitumen fraction of the oil sands are resolved according to their spin-spin relaxation times into three major groups: solid-like (rigid), solid-like (mobile) and semi-liquid. The water in the oil sands exists in two different environments. Tentatively one environment is assigned to be the bridges between the sand grains, while the other is assigned to be the clay surface. One can conclude that with spin grouping of complex mixtures the decomposition (in which components are resolved according to their dynamic state) is possible. The accuracy of such resolution is of the order of a few per cent.
Different roles for internal standards in PIXE analysis of fluid residues are discussed. The efficacy of internal standards is predicated on having homogeneous targets of uniform thickness; the use of lecithin additiv...
详细信息
Different roles for internal standards in PIXE analysis of fluid residues are discussed. The efficacy of internal standards is predicated on having homogeneous targets of uniform thickness; the use of lecithin additives to achieve this is described and data are presented to illustrate the dependence of analytical precision on the mode of specimen preparation. Determination of actual thickness via measurement of the energy loss of transmitted protons is demonstrated; this provides a means of correcting for departures from the much-quoted “thin target” criterion.
The lattice spectra of solid CCl 4 , monoclinic phase II, have been re-examined at higher resolution. The greatly increased number of observed peaks is now consistent with that expected for a crystal with 16 molecules...
The lattice spectra of solid CCl 4 , monoclinic phase II, have been re-examined at higher resolution. The greatly increased number of observed peaks is now consistent with that expected for a crystal with 16 molecules per unit cell, if it is assumed that only modes of a predominantly translational nature are detected.
It is demonstrated that the non-linear effects in the indirect ion-ion interaction, via the valence electrons, are primarily responsible for the anomalous features present in the observed S ( q )'s of In and Tl bu...
It is demonstrated that the non-linear effects in the indirect ion-ion interaction, via the valence electrons, are primarily responsible for the anomalous features present in the observed S ( q )'s of In and Tl but are responsible to a much lesser extent for those in Ga, Sn and Bi.
Monoenergetic X-ray lines produced by diffraction from a curved crystal monochromator have been used to test the applicability of the Hypermet function for Si(Li) detectors. Excellent fits are achieved; the function&#...
详细信息
Monoenergetic X-ray lines produced by diffraction from a curved crystal monochromator have been used to test the applicability of the Hypermet function for Si(Li) detectors. Excellent fits are achieved; the function's parameters vary smoothly with energy, and the intensity of the non-Gaussian peak components correlates with the thickness of the frontal dead layer where charge collection is incomplete. Accurate silicon escape peak intensities are presented and the contribution to the lineshape from Compton-scattered events is discussed qualitatively.
作者：
ISENOR, NRUniversity of Waterloo
Guelph-Waterloo Program for Graduate Work in Physics Centrefor Molecular Beams and Laser Chemistry Waterloo Ontario N2L 3G1.
暂无评论