“Microanalysis of individual silver halide microcrystals”. Wu S, van Daele A, Jacob W, Gijbels R, Verbeeck A, de Keyzer R, , 1612 (1992)
Keywords: P3 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
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“Defect induced thickness growth in silver chloride (111) tabular crystals: a TEM study”. Van Renterghem W, Schryvers D, van Landuyt J, Bollen D, Van Roost C, De Keyzer RB, , 38 (2000)
Abstract: Defects in AgG tabular crystals with {111} surfaces are characterised by transmission electron microscopy (TEM) and their influence on the growth process is discussed. In the tabular crystals, twins parallel to the tabular face as well as dislocations along different directions are observed. The twins induce the tabular growth, while the dislocations do not influence the morphology. In 10 to 30% of the crystals that have been characterised, thickness growth is observed and it is shown that in all cases twins on other planes than the tabular ones are present. Two configurations occur more frequently and are analysed in detail. For the first group, twins parallel to the tabular face as well as a microtwin along a non-parallel {111} plane and ending inside the crystal are present. In the crystals of the second group only one extra non-parallel twin occurs giving rise to a bicrystal built up by a tetrahedral shaped part and a flat triangular or trapezoidal part. More complex twin configurations give rise to various, less characteristic morphologies.
Keywords: P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
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“The influence of the precipitation method on defect formation in multishell AgBrI (111) tabular crystals”. Van Renterghem W, Karthauser S, Schryvers D, van Landuyt J, De Keyzer R, Van Roost C, , 167 (2000)
Abstract: Multishell tabular grains have a higher speed than pure AgBr tabular grains. Usually the shells differ in size and iodide content, but also the precipitation method for the iodide containing shells has an influence on the iodide incorporation. A TEM investigation was performed to determine the defect structure of multishell AgBr (111) tabular crystals containing a shell with a low iodide concentration and one with a high iodide concentration. The twins that induce tabular growth and stacking fault contrast in the region of the iodide shells have been observed, similar to previously studied AgBr/Ag(Br,I) coreshell crystals. Moreover in some of the crystals dislocations have been observed, sometimes even an entire network. The number of dislocations formed varies for the different methods of iodide addition. Also variations in average thickness between the different iodide addition methods have been observed. A higher number of dislocations and thicker crystals point towards a higher local concentration of iodide. These observations allow deciding which iodide incorporation method is most useful for a preferred dislocation pattern.
Keywords: P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
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“Functioning of thiocyanate ions during sulphur and sulphur-plus-gold Sensitization”. Charlier E, Gijbels R, Van Doorselaer M, De Keyzer R, , 172 (2000)
Abstract: Not much about the effect of thiocyanate addition on the sulphur ripening is known, although it is used for many applications in photographic practice. Via a combination of tracer analysis and diffuse reflectance spectroscopy the effect of thiocyanate addition on the sulphur and sulphur-plus-gold ripening could be unveiled. When thiocyanate is added prior to the sulphur addition, it appears to rearrange the silver halide surface in such way that the sulphur deposition rate is enhanced, but the supply of interstitials is limited. Addition of thiocyanate after the sulphur reaction results in the formation of thiocyanate complexes with silver, from which a silver ion is more easily deposited in a surface cell of the silver sulphide clusters thus enhancing the sensitization rate. For sulphur-plus-gold sensitized emulsions it was observed that part of the gold ions could be removed out of the Ag2-xAuxS clusters by addition of thiocyanate ions and subsequent washing. Hence, it was concluded that two different types of gold ions are present in the silver sulphide clusters; 1. gold ions which are substitutional for silver (bound between sulphur and bromide ions) 2. gold ions which bridge two or three sulphur atoms. Incorporation of gold ions into silver sulphide clusters suppresses their optical absorption in diffuse reflectance spectroscopy. Since the optical absorption at 505 nm can completely be restored by addition of thiocyanate, it is assumed that the entity absorbing at this wavelength is a monomer of silver sulphide.
Keywords: P1 Proceeding; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
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“The chemical characterization of silver halide microcrystals”. Geuens I, Gijbels R, Jacob W, Verbeeck A, de Keyzer R, , 251 (1993)
Keywords: P3 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
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“Depth profiling of silver halide microcrystals”. Geuens I, Gijbels R, Jacob W, Verbeeck A, de Keyzer R, , 479 (1992)
Keywords: P3 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
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“Quantitative surface analysis of silver halide microcrystals using scanning ion microprobe and scanning Auger microprobe”. Janssens G, Geuens I, de Keyzer R, van Espen P, Gijbels R, Hubin A, Terryn H, Vereecken J Wiley, Chichester, page 161 (1996).
Keywords: H3 Book chapter; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Chemometrics (Mitac 3)
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