Study on the growth mechanism of Bi-2212 ribbon-like thin films on flat Ag substrate by the atomization technique
The growth mechanism of Bi-2212 ribbon-like thin films on flat Ag substrate using an atomization technique was studied. The fine Bi-2212 powders were dispersed on the Ag substrate before the melting process, so as to avoid the change in the composition of the molten phase with distance, which would result in the formation of the impurity phases. Nearly reversible peritectic reaction on cooling causes the formation of well-defined Bi-2212 phase. Based on the results of in situ high temperature microscope observation, the wetting of the molten phase to the growing ribbons was identified as the essential condition for the growth of the ribbon-like thin films.
High-temperature X-ray diffraction study of the peritectic reactions of Bi-2212 with and without Ag additions
Abstract High-temperature X-ray diffraction (HTXRD) was used to determine the peritectic melting sequence of Bi2Sr2CaCu2O8 (Bi-2212) and Bi-2212 + 20 wt.% Ag thick films on MgO substrates. The residual carbon concentration of all samples was reduced to 1600 ppm by careful thermal treatment before the HTXRD analyses. Analysis of samples quenched in oil using XRD and EMPA supports the HTXRD results. Lattice-parameter analyses were used to determine the compositions of solid solutions present in the reaction sequence. In the case of pure Bi-2212, two phases form immediately on melting at 870°C, namely (Cax, Sr1−x)CuO2 (1:1) and an unidentified phase. The unidentified phase decomposes by 900°C, while the 1:1 phase is present up to 920°C. (Ca1.4Sr0.6)CuO3 (2:1) forms by 880°C, immediately after the 1:1 phase, and decomposes by 930°C, while (Ca0.96Sr0.04)O appears at 900°C, and coexists with the liquid up to at least 1350°C. Only slight changes in the solid-solution compositions were found with 20 wt.% Ag added to the system, with the phases and stability regions remaining the same.
Looking for regional words in late seventeenth-century England: Bishop White Kennett and his glossary to Parochial Antiquities (1695) 1
The analysis of regional dialects in the Early Modern period has commonly been disregarded in favour of an ample scholarly interest in the ‘authorised’ version of English which came to be eventually established as a standard. The history of regional ‘Englishes’ at this time still remains to a very great extent in oblivion, owing mainly to an apparent dearth of direct textual evidence which might provide trustworthy data. Research in this field has been for the most part focused on phonological, orthographical and morphological traits by virtue of the rather more abundant information that dialect testimonies yield about them. Regional lexical diversity has, on the contrary, deserved no special attention as uncertainty arises with regard to what was provincially restricted and what was not. This paper endeavours to offer additional data to the gloomy lexical setting of Early Modern regional English. It is our aim to give a descriptive account of the dialect words collated by Bishop White Kennett’s glossary to Parochial Antiquities (1695). This underutilised specimen does actually widen the information furnished by other well known canonical word-lists and provides concrete geographical data that might contribute to bridging the gaps still existing in the history of lexical provincialisms at the time.