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排序方式: 共有114条查询结果,搜索用时 31 毫秒
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Marian Olszowy Ewa Markiewicz Czesław Pawlaczyk Ewa Nogas-Ćwikiel 《Phase Transitions》2013,86(11-12):1099-1106
Dielectric response of poly(vinyl chloride), (PVC), loaded with different amount of Ba0.3Na0.7Ti0.3Nb0.7O3 (BNTN) ceramic powders was investigated in frequency range 100 Hz–1 MHz and temperature range 100–450 K. Ceramic solid solution of barium titanate and sodium niobate with composition Ba0.3Na0.7Ti0.3Nb0.7O3 was obtained from BaCO3, TiO2, Na2CO3 and Nb2O5 by conventional method. Powders were prepared by grinding of ceramics. The obtained ceramics, used to produce BNTN–PVC composites, are characterized by the relaxor behaviour with a broad peak of dielectric permittivity ε′ at T m ≈ 230 K. The microstructure of the powders was observed and the grain size was estimated using scanning electron microscope Hitachi S-4700. The EDS analysis confirms the qualitative and quantitative chemical composition of powders and ceramics. The BNTN–PVC composite samples of 0-3 connectivity were prepared from ceramic and polymer powders by hot-pressing method. The dielectric response of the composites displays features originated from the PVC polymer modified by those of BNTN ceramics. The relaxation time of the α-process of PVC obeys the Vogel–Fulcher law and decreases with increasing volume fraction of the ceramics. 相似文献
93.
The aim of this paper is to numerically investigate the characteristics of the Electrical Double Layer in electrolytes. The surface adsorption is neglected, which means there is no electric current injected to the solution from the electrode. The analysis is done for a one-dimensional model as the Debye length for electrolytes is much smaller than other dimensions of the system. The discussion is focused on the behaviour of the electric current and the layer impedance at different frequencies of the supply voltage. 相似文献
94.
Wanda Radecka‐Paryzek Izabela Pospieszna‐Markiewicz Maciej Kubicki 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(7):o399-o401
In the title salt, also known as pentane‐1,5‐diammonium dichloride, C5H16N22+·2Cl−, the cation exists in an ideal fully extended conformation and lies on a mirror plane in the space group Pbam. In the crystal structure, layers of cations are hydrogen bonded with Cl− anions, which occupy the space between the layers. This kind of packing leads to a short unit‐cell parameter of 4.463 (1) Å. This structure is another case of centro–non‐centrosymmetric ambiguity; the best results were obtained in a centrosymmetric space group, with the disordered NH3 groups accounting for the non‐centrosymmetric `component'. 相似文献
95.
Roksana Słowik 《Linear and Multilinear Algebra》2016,64(9):1760-1768
96.
Fourest T. Bouda P. Fletcher L. C. Notta-Cuvier D. Markiewicz E. Pierron F. Langrand B. 《Experimental Mechanics》2020,60(2):235-248
Experimental Mechanics - In the present work Image-Based Inertial Impact (IBII) tests are performed on Ti6Al4V material. The IBII test uses an impact on the edge of the specimen to generate a short... 相似文献
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Thermal decomposition of 4,4′-dipyridyl complexes of light rare-earth thiocyanates in air atmosphere
D. Czakis-Sulikowska J. Radwanska-Doczekalska M. Markiewicz 《Journal of Thermal Analysis and Calorimetry》1994,41(1):81-89
The thermal decompositions of Ln(NCS)3(4-dipy)2·5H2O were studied, whereLn=La, Pr, Nd, Sm, Eu and Y, and 4-dipy=4,4′-dipyridyl. The compounds are first dehydrated. During the thermal decomposition
of Ln(NCS)3(4-dipy)2, deamination takes place. The transient products decompose with the formation of Ln2O2SO4. The energies of activation for the first step of dehydration of the La, Pr, Nd, Sm and Eu complexes were determined.
Zusammenfassung Es wurde die thermische Zersetzung von Ln(NCS)3(4-dipy)2.5H2O mitLn=La, Pr, Nd, Sm, Eu, Y und 4-dipy=4,4′-Dipyridyl untersucht. Die Verbindungen werden zuerst dehydratiert. Bei der thermischen Zersetzung von Ln(NCS)3(4-dipy)2 findet eine Desaminierung statt. Die übergangsprodukte zersetzen sich unter Bildung von Ln2O2SO4. Die Aktivierungsenergie für den ersten Schritt der Dehydratation der La-, Pr-, Nd-, Sm- und Eu-Komplexe wurde ermittelt.相似文献
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