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161.
A. Torrisi P. Horák J. Vacík A. Cannavò G. Ceccio J. Vaniš 《Phosphorus, sulfur, and silicon and the related elements》2020,195(11):932-935
AbstractOn the perspective to develop CuO–TiO2 MOS, multilayered Cu and Ti thin layers were alternatively deposited on silicon wafers using 25?keV Ar?+?ion beam sputtering and, subsequently, oxidized by thermal annealing in air at 400?°C for 24?h. The deposited films have variable ratios of the Cu and Ti % at. One of the main goal is to obtain such multilayers avoiding the presence of Cu–Ti–O compounds. The samples were characterized in terms of composition (by RBS and SIMS analyses) and morphology (by AFM and SEM investigations). In particular, SIMS maps allows to observe the spatial distribution and thickness of each phase of the Cu/Ti multilayers, and further to observe Cu diffusion and mixing with Ti, as well as phase separation of CuO and TiO2 in the samples. The reasons of this effect represent an open issue that has to investigated, in order to improve the MOS fabrication. 相似文献
162.
J. Málek J. šesták F. Rouquerol J. Rouquerol J. M. Criado A. Ortega 《Journal of Thermal Analysis and Calorimetry》1992,38(1-2):71-87
The applicability of both conventional Thermal Analysis (TA) and Controlled Rate Thermal Analysis (CRTA) for kinetic analysis is discussed. It is shown that TA method can give a reliable kinetic information and meaningful kinetic parameters especially for solid state transformation. On the other hand the CRTA method is more suitable for decomposition process where one or more gasses are evolved. A consistent and reliable method of kinetic analysis is proposed for both techniques. This method is illustrated to analyze the crystallization process of chalcogenide glass and the decomposition of dolomite. 相似文献
163.
D. Reichardt V. Bonačić-Koutecký P. Fantucci J. Jellinek 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1997,40(1):486-489
An ab-initio molecular dynamics procedure without precalculation of the Born-Oppenheimer energy surface based on an iterative non-local density functional method employing Gaussian atomic basis has been developed. Analytical gradients are calculated and used for the propagation of nuclei. Sufficiently long trajectories can be calculated at an acceptable computational cost, allowing for analysis of dynamical behaviour of small metallic clusters. This is illustrated on an example of the Li8 cluster. Temperature behaviour of different type of isomers has been investigated. Calculated power spectra allow to identify the presence of more than one isomeric forms along the given trajectories. 相似文献
164.
Laila Čakare Marija Kosec Barbara Malič 《Journal of Sol-Gel Science and Technology》2000,19(1-3):603-606
PbZrO3 (PZ) thin films have been prepared by 2-methoxyethanol route from lead oxide or lead acetate and zirconium n-butoxide. The use of lead oxide as lead source and the seeding layer of TiO2 on Pt/TiO2/SiO2/Si substrate facilitate the formation of the perovskite phase. 相似文献
165.
I. Kúdelka P.K. Misro J. Pospíšil H. Korbanka T. Riedel G. Pfahler 《Polymer Degradation and Stability》1985,12(4):303-313
The hydroperoxide decomposing efficiencies of dioctadecylsulfide (I), dioctadecyldisulfide (IV) and dioctadecyl 3,3-thio-dipropionate (VII) have been compared at 75°C and 85°C. The formation of oxidation products from (I) and (IV) has been checked. Experimental evidence is given of the important rôle of the activation of the molecule of (IV) by the presence of two sulfidic sulfur atoms compared with the activation of the sulfur atom in (VII) by the alkoxycarbonyl group in the beta position. The explanation of the high efficiency of disulfide has been based on the formation of thiosulfinate—the key intermediate for the generation of peroxidolytic species—in the first reaction step. 相似文献
166.
The paper deals with the problem of the outpatient administration of186Re-HEDP and153Sm-EDTMP for palliative therapy of bone metastases. The subsequent 6 hours stay of the treated patients in a department of nuclear medicine appears to be in compliance with regulations proposed in the Czech Republic as well as with ICRP recommendations. 相似文献
167.
Due to the high safety risks, chemistry instructors avoid demonstrating many remarkable experiments based on the addition of a liquid to a solid. Well-known examples of such demonstrations are various pyrotechnic mixtures of potassium chlorate and sugar (sucrose), which are usually activated with a drop of concentrated sulfuric acid. Other attractive demonstrations are the addition of water to freshly prepared magnesium phosphide and addition of water to burning magnesium. In all of these demonstrations the reaction that takes place immediately is very vigorous and can be hazardous for the instructor. Because chemistry teachers and instructors usually try to avoid performing experiments that include a hazard, a number of highly attractive experiments may remain unknown to the public. Using a simple homemade device called a safety dropper, one can perform all of these experiments with complete safety, both for the audience and the demonstrator. Details for performing some of these experiments as well as for the construction of the safety dropper are given in this paper. Video clips of demonstrations are included as an aid for inexperienced instructors. 相似文献
168.
169.
The phase diagrams of the binary system KF-AlF3 as well as the ternary system NaF-KF-AlF3 in the range up to 50 mol% AlF3, were measured using the thermal analysis method. In the system KF-AlF3 the coordinates of the eutectic points are: E
1: 8.0 mol% AlF3, 821.2°C, and E
2: 45.5 mol% AlF3, 565.0°C. In the investigated concentration range of the ternary system 2 eutectic points have been found with the calculated
coordinates: E
1: 36.3 mol% NaF, 62.7 mol% KF, 1.0 mol% AlF3; t=711.2°C; and E
2: 51.9 mol% NaF, 27.4 mol% KF, 20.7 mol% AlF3; t=734.5°C. Other eutectic points lie most probably beyond the investigated part of the system.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
170.
Data on the structures and reactions of heterocyclic diazo compounds that lead to the formation of new heterocyclic systems as a result of intra- or intermolecular cyclization and rearrangements are systematized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 579–603, May, 1980. 相似文献