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Fabrics made from natural fibers, such as wool and cotton, are susceptible to attacks from micro-organisms, which may damage the fabrics and harm the human body. Antimicrobial finishing of natural textile products may involve harmful and non-environmentally friendly chemicals. In this study, a natural antibacterial agent, capsaicin, was coated on the surface of wool fabrics by a sol-gel process. The antibacterial properties of coated fabrics were evaluated against test bacteria Escherichia coli according to the American Association of Textile Chemists and Colorists (AATCC) method and standard American Society for Testing and Materials (ASTM) E2149-01. Compared with the control group (sol-gel coated fabric without capsaicin), the capsaicin-coated fabric inhibited bacterial growth markedly after 24 hours incubation at 37 C. The antibacterial efficiency after laundry washes was also investigated. Good durability to washing of capsaicin on fabric was achieved by the sol-gel coating technique.

Nine indole and benzimidazole cyanine dyes, used as green-sensitizing dyes in photographic emulsions, are synthesized. The compounds are characterized from mass spectrometric and NMR spectroscopic data, and elemental analysis. FAB mass spectrometry proved to be an efficient method for determining the structure of the compounds. From UV-VIS data of the compounds the sensitizing properties of the cyanine dyes are predicted. The reflection spectrum of Gs2-9 coated in photographic emulsions showed J-aggregation behaviour at A = 560 nm. Unsymmetric benzimidazole-indole cyanine dyes showed good to excellent green sensitizing properties in photographic emulsions, whereas symmetric indole cyanine dyes showed heavy residual colour and no sensitizing properties.

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The mechanism of hologram formation in dichromated gelatin is studied from all aspects with x-ray photoelectron spectroscopy (XPS). It is indicated that the Cr 2p(3/2) XPS spectrum of chromium used for hologram formation shows the property of exhibiting a continuous spectrum during the process of dichromated-gelatin hologram formation. By means of curve fitting and drawing a comparison between the obtained spectra and those of some standard substances, it is found that during the process of hologram formation the valence of chromium used for hologram formation changes from Cr6+ to a quasi-trivalent state to Cr4+, and finally to Cr3+. Accordingly, the corresponding compound experiences a change from (NH4)2Cr2O7 to the transient state close to the feature of Cr(OH)3 to CrO2, and finally to Cr3+, cross linking with the gelatin. The essence of the chemical change at different stages of the process of hologram formation was found, and so the present mechanism, which is determined with comparatively abundant proof, should replace previously reported mechanisms, which were too simple, varied, and sometimes even mutually contradictory. According to the experimental results and the fact that a solid-film reaction, which differs from that of the liquid-phase reaction, was studied, possible chemical-reaction equations of the process of hologram formation are established. This becomes the basis for explaining previous findings and expanding further research.