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181.
Phase relations in the composition range from to were studied by electrical-conductivity measurements and X-ray diffraction in the ranges and . The plot of log σ versus log showed straight lines with distinct slopes, which corresponded to four regions (, , and ). The existence of the hyperstoichiometric phase was suggested in the temperature range from 1025 to 1126°C. The peritectoid temperature () was estimated to be present between 1126 and 1131°C. The partial free enthalpies and entropies for the two-phase equilibrium (, and ) were calculated and compared with previous results. From the dependence of the electrical conductivity on the oxygen partial pressure the nonstoichiometric defect structures of and were interpreted as consisting of doubly charged oxygen interstitials (Oi'') and doubly charged oxygen vacancies (VO''). At room temperature, the homogeneity range of the U4O9 phase was investigated with a Debye-Scherrer camera. 相似文献
182.
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185.
The nonstoichiometric composition of was measured by means of thermogravimetry in the range of and . The compositional deviation from stoichiometry, , in the hyperstoichiometric Cr2O3+x phase was observed to be smaller than 2 × 10?4, irrespective of temperatures, provided that the hyperstoichiometric Cr2O3+x exists. The existence of the hypostoichiometric Cr2O3?x phase was first established in this study in the region of low oxygen partial pressure below 10?5 Pa. From the oxygen partial pressure dependence of in Cr2O3?x, the defect structure was discussed with the neutral chromium interstitials in the composition near stoichiometry and with the triply charged ones far from stoichiometry. The partial molar enthalpy and entropy of oxygen of Cr2O3?x showed the complex compositional dependences, suggesting the change of the type of the predominant defect. 相似文献
186.
The vapor pressures over nonstoichiometric NbO2 ± x(s) (1.972?2.037) were measured by mass-spectrometric method in the temperature range 1958–2326 K. The congruently vaporizing composition in the NbO2 ± x phase was determined to be stoichiometric NbO2.000 from the composition dependence of the total vapor pressures. The partial pressures of oxygen were calculated as a function of temperature and O/Nb composition from the partial pressures of the gaseous species NbO2(g) and NbO(g) over nonstoichiometric NbO2 ± x, from which the partial molar enthalpies and entropies of oxygen were calculated as a function of O/Nb composition. The composition dependence of the partial molar enthalpy and entropy obtained suggested the existence of some kind of short-range ordering in the nonstoichiometric NbO2 ± x(s) phase. The enthalpies of formation of nonstoichiometric NbO2 ± x(s) were also determined as a function of composition by combining the partial molar enthalpies of oxygen with the enthalpy of formation of stoichiometric NbO2.00(s). The phase diagram around NbO2 ± x at high temperatures was determined from the vaporization study. 相似文献
187.
Noriaki?koudaEmail author Nobuyuki?Matsui Haruhiko?Nishimura Ferdinand?Peper 《Neural Processing Letters》2005,22(3):277-290
The Qubit neuron model is a new non-standard computing scheme that has been found by simulations to have efficient processing
abilities. In this paper we investigate the usefulness of the model for a non linear kinetic control application of an inverted
pendulum on a cart. Simulations show that a neural network based on Qubit neurons would swing up and stabilize the pendulum,
yet it also requires a shorter range over which the cart moves as compared to a conventional neural network model. 相似文献
188.
The high temperature transition in U4O9 has been studied by electrical conductivity measurements and X-ray diffraction. From the electrical conductivity measurements, a similar variation of log σ with reciprocal temperature to that in the transition range near room temperature is observed in the temperature range from about 300 to 800°C. Like the low temperature transition, a small lattice contraction is also observed in that temperature range by means of X-ray diffractometry, and the transition temperature increases from 530 to 620°C with increasing O/U ratio. After the transition the intensity of superlattice reflections increases, but that of superlattice reflections disappears. The mechanism of this high temperature transition is considered to be a second-order transition of the order—disorder type based on the configurational change of U4+ and U5+ with the shift of some portions of the lattice oxygen atoms from the lattice sites to the interstitial positions. The phase diagram of U4O9 is presented on the basis of the electrical conductivity and X-ray data. 相似文献
189.
Kiyoshi Itoh Katsumi Muramatsu Mabito Matsui Shigemichi Suzuki 《Computers & Graphics》1982,6(2):47-61
Network analysis is powerful in building formal network models of various computational systems or social systems and obtaining their functions and performance exactly because of simplicity of binary relations in networks. Traditionally, it takes lots of effort in network analysis because network analysis was performed by the use of lots of numerical data in batch processing form. Effective network analysis activity, satisfying the system requirements based on consideration for such traditional manner with high cost, requires semiautomatic or computer aided man-machine facilities with interactive editing, analysis, and result viewing functions. We have developed Graphical Editing and Analysis system for Network System (Geans) on DEC PDP-11/34 minicomputer with a graphic display which enables us to edit or modify various network representations and analyze their qualitative and quantitative property, smoothly and interactively with the use of graphics and data abstraction. Geans is composed of a network editing system with effective use of a graphic display, a network data management system with systematic use of network data abstraction, a network analysis system with construction of shared library routines and specific object problem oriented routines, and a node/arc shape definition system. Geans has been applied to various network models such as a transportation analysis problem, PERT/CPM planning, Petri Net analysis and a guidance system for an urban railway network, and moreover it is being applied to other analysis areas as evolving itself. 相似文献
190.
In addition to CD4+ T lymphocytes, cells of monocyte/macrophage lineage are a major target for human immunodeficiency virus type 1 (HIV-1) infection. In vitro studies of HIV-1 infection in human monocyte-derived macrophages can be undertaken by a reproducible cell-based assay. A macrophage-based infectivity assay was developed based on the semi-quantitative scoring of HIV-1 induced cytopathology in monolayer macrophage cultures. The assay exhibited dilution-dependent linearity with all three primary macrophage-tropic isolates tested. The end-point infectivity titers determined by this assay correlated with the results obtained by detecting viral p24 antigen in the culture supernatant. The applications of the assay in both neutralization and anti-viral protocols yielded identical results with the more time-consuming and costly p24 formats. Since the assay offers a simple and low-cost method of measuring HIV-1 infectivity in human primary macrophages, it can be used quite easily for large-scale screening or evaluation of candidate vaccines and anti-viral agents. 相似文献