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991.
992.
The literature data on ternary structural analogues of the compound Tl5Te3 and multicomponent phases based on them are systematized. This class of inorganic substances is of considerable scientific and practical interest as promising functional materials having thermoelectric, optical, and magnetic properties, as well as topologically protected surface states and superconductivity. The focus of the survey is on phase equilibria in ternary and more complex systems where structural analogues of Tl5Te3 are formed. Crystalstructure features, thermodynamic and some physical properties of these compounds and phases of variable composition are considered.  相似文献   
993.
In the present paper, a new approach was developed for solving the problem of time synchronization of a set of signals obtained by different measurement techniques without a common trigger. The recorded signals were the result of sparks and bursts generated by a repetitive Marx generator. A thermal imaging camera, a high speed camera and an audio recorder were used to obtain the necessary data for synchronization and characterization. Moreover, a piezoelectric sensor was applied for shock waves characterization during the early stages of bursts. In the first place, different data with evident time shifts were acquired. Then, A set of simple operations such as maximum selection and localization, threshold comparison, Euclidean distance calculation and minimization were employed for signal analysis and pattern matching to ensure a good data synchronization, which allowed a detailed analysis of the phenomenon in the end.  相似文献   
994.
In this paper, we have studied the hybrid projective synchronisation for incommensurate, integer and commensurate fractional-order financial systems with unknown disturbance. To tackle the problem of unknown bounded disturbance, fractional-order disturbance observer is designed to approximate the unknown disturbance. Further, we have introduced simple sliding mode surface and designed adaptive sliding mode controllers incorporating with the designed fractional-order disturbance observer to achieve a bounded hybrid projective synchronisation between two identical fractional-order financial model with different initial conditions. It is shown that the slave system with disturbance can be synchronised with the projection of the master system generated through state transformation. Simulation results are presented to ensure the validity and effectiveness of the proposed sliding mode control scheme in the presence of external bounded unknown disturbance. Also, synchronisation error for commensurate, integer and incommensurate fractional-order financial systems is studied in numerical simulation.  相似文献   
995.
In this research, we work on a specific class of nonlinear evolution equation which is the modify unstable nonlinear Schrödinger equation. This equation is used to describe a time evolution of disturbances in unstable media. Various solutions have been obtained. The results deduced are of varied types and include bright solution, dark solution, rational dark-bright solution, as well as cnoidal solutions. These solutions might be useful in engineering fields. Some conditions for the stability of these solutions are presented. The method used here is understandable and very powerful for solving the nonlinear problems.  相似文献   
996.
It has been shown that plasma inhomogeneity reduces the threshold of the parametric instability of two-plasmon decay and, in particular, allows the excitation of plasmons with the same frequency by a spatially uniform pump field.  相似文献   
997.
Russian Journal of Organic Chemistry - A procedure has been developed for the sonochemical synthesis of 5,6-dihydro[C70-D5h(6)][5,6]- (1,4-dioxano)fullerene on the basis of heterogeneous reaction...  相似文献   
998.
There are presented measurements of the NMR field shifts for aqueous protons in aqueous solutions containing paramagnetic inorganic compounds of Cu2+, Cr3+, Fe3+ and Mn2+ ions. The measurements have been performed on samples in the form of transversally magnetized long cylinders using both the internal and external NMR standards. The experimentally determined shifts are related to the NMR field position of protons in pure water. The results for demagnetizing shifts are compared with the data which were computed from the magnetic susceptibility values (measured by magnetostatic method), the chemical shifts are compared with the results of other authors. Results of measurements indicate a small chemical shift of internal standards in some solutions.  相似文献   
999.
1000.
57Fe NMR spin-echo spectra, static magnetization and X-ray diffraction measurements for Cd0.1Cu0.9Fe2O4 ferrite taken in a wide range of temperatures are presented. The X-ray studies show that above 100 K the structure is cubic. The temperature dependence of the effective magnetic field acting on 57Fe nuclei at non-equivalent tetrahedral and octahedral sites has been determined. Different thermal behaviour of the magnetic field at both sublattices and of the specific macroscopic magnetization have been found. Magnetization measurements imply that cadmium substitution does not affect the ferric ion distribution between the sublattices of the ferrite.  相似文献   
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