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Copyright of Uzbek Chemical Journal / O'Zbekiston Kimyo Jurnali is the property of Institute of General & Inorganic Chemistry of Academy of Sciences of Republic of Uzbekistan and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper describes the formation of "sandwich" wulfenite. Banded wulfenite from the Ojuela Mine, Mapimí, Durango, Mexico, have been found since 2017, but an explanation for the band formation has not been provided. X-ray diffraction (XRD) showed the wulfenite to have a tetragonal unit cell of a = 5.4374(1), c = 12.1123(7) Å. The Raman spectrum was dominated by ν1 (Ag) around 870 cm-1, while the weak shoulder at 859 cm-1 represents the strain activated ν1 (Bu) infrared (IR) band. Two ν2 modes were observed at 318 cm-1 (Ag) and 351 cm-1 (Bg). For the ν3(Eg), the band at 768 cm-1 was assigned to the Bg symmetric mode and the 745 cm-1 band to the Eg vibration. The IR spectrum showed two strong bands at 835 and 779 cm-1 corresponding to v3 modes and a very weak one at 496 cm-1. SEM-EDX (scanning electron microscopy - energy dispersive X-ray analysis) showed that the band does not extend into the main crystal but is limited to the surface as secondary growth. The main thick tabular crystal was dominated by {001}, {110}, and {111}. The {001} surfaces of the wulfenite crystals showed evidence of later dissolution, which may have been part of the source material for this secondary crystallization. The chemical composition of the main wulfenite crystal proved only minor substitution of W for Mo. Contrastingly, a much higher number of substitutions by V, As, and W for Mo - as well as Ca, Fe, Zn, Cu, and Al for Pb - was observed in the secondary band, indicating a change in the fluid composition from which the band crystallized compared to the original wulfenite. Changes in lattice parameters of the secondary wulfenite crystals and the energy involved in nucleation on the surface of the original wulfenite as well as the different bonds exposed on different faces favored the formation of the band on only {110}. [ABSTRACT FROM AUTHOR]

The paper tackles the influence of skin surface lipids and chromatic fungal attack on the paper support and the writing of a 125-year-old document, which involves the corroboration between multianalytical techniques. Thus, the study used three specimens sampled from different areas: a standard lipid- and fungal-attack-free sample, one with old lipid film dating back to its being used by its creator (before it had entered the archives) and another with lipid film and fungal attack present on it (from after it had entered the archives). In addition to direct observation by means of magnifying instruments, our scientific research relied on the following techniques: OM, SEM-EDX, μ-FTIR and differential thermal analysis (TG, DTA and DTG). Compared to the standard sample, the data of which correspond to the natural aging process occurring between 1895 and 2020, the other two samples show evolutionary degradation effects under the influence of oxidatively fouled lipids and on small areas photochemically and thermally cornified, as well as effects due to enzymatic degradation under the influence of fungal attack. The study has a clear goal, namely to implement specific protection measures when dealing with old documents (gloves and protective mask, air conditioning niche for preservationrestoration actions). [ABSTRACT FROM AUTHOR]

Copyright of Iraqi Journal of Agricultural Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Long term cultures of human bone marrow cells on poly(L-lactide-co-D,L-lactide) 70 : 30 and 90 : 10 plates were observed by means of scanning electron microscopy (SEM), SEM-EDX (SEM combined with energy dispersive X-ray analysis), flow cytometry, histochemical stainings, and culture medium analysis. After 14 days culture, cell numbers were only slightly lower compared with our reference material, hydroxyapatite, and much higher compared with polyethylene. There was evidence of collagenous matrix production with osteoblast activity. Acridine orange stainings as well as flow cytometry after incubation with propidium iodide showed only a few non-viable cells. By means of flow cytometry, we found about 30% of cells with granulocyte-markers, some monocyte-derived cells, and only small amounts of lymphocytes. After 9 weeks culture, there was evidence of calcium-phosphate deposition with extracellular matrix. There were only slight differences between the two tested polymers. Our culture system with human bone marrow cells plated on two bioresorbable polymers suggests a biocompatibility almost as good as hydroxyapatite, which is usually well tolerated. There was even evidence of mineralized collagenous matrix after some weeks of culture, which was detected earlier than the mineralization of cell-free controls. [ABSTRACT FROM AUTHOR]