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Powder mounting

Regardless of which type of preferred orientation is present in the sample, it will in its own and systematic way affect diffracted intensities. In severe cases, nothing more than lattice parameters (if any) can be determined from highly textured powder diffraction data since it is impossible to precisely account for the changes in the diffracted intensity caused by the exceedingly non-random distribution of particle orientations. [Pg.291]

Razor blade or glass slide Excess powder [Pg.292]

Cylindrical specimens are usually prepared by sinking a thin glass capillary into a liquid binder (e.g., purified petroleum jelly or liquid varnish) and then by dipping the capillary into a loose powder. Alternatively, powder can be mixed with oil to a consistency of thick slurry and then the capillary is simply dipped into the mixture. In both cases, the capillary may need to be exposed to the powder several times to ensure complete and uniform coverage of its surface. [Pg.294]

In some instances, especially when the studied powder is air or moisture sensitive, it can be placed inside a low absorbing glass capillary (e.g. a borosilicate glass), after which the capillary is sealed. Filling capillaries with powders is usually a tedious process and it requires larger diameter capillaries than those usually used for surface coverage. Furthermore, it may [Pg.294]


Graf, D.L., 1974. X-ray cells for diffraction analysis of flat powder mounts in contact with liquid at elevated temperature and pressure. Am. Mineral., 59 851—862. [Pg.311]

Semi-quantitative bulk-rock XRD analyses were carried out on 23 samples (Table 3), which were ground in a Siebtechnick mill and prepared as pressed powder mounts. Continuous scans were run of these powder pressings from 3° to 75° 2 0, at 2°/min, and the Co X-ray tube was operated at 50 kV and 30 mA, on a Philips PW1050 dififracto-... [Pg.335]

Raw X-ray diffraction data, either digital or acquired on a strip recorder, are used make mineral identifications as summarized above. Whole sample data collected from random powder mounts are compared to patterns of known minerals either manually or using a computer search-match program such as /zPDSM (Marquart, 1986). Because each component in a mixture of crystalline materials produces its own characteristic pattern that is independent of others, the identification process becomes one of simply unscrambling the superposed patterns. [Pg.168]

In 1897 Tbrnebohm, a Swedish investigator, possibly realizing that because of compositional variation mineral names mightbe better suited for clinker phases than chemical formulas, clearly described the optical features of the principal clinker phases in thin sections and powder mounts and coined the terms alite, belite, celite, felite, and also glassy residue. Tbrnebohm stated that "belite "has two or three sets of cross striations and felite" has one set of parallel striations formed at low temperature. Tbrnebohm related microscopical data to burning conditions, stating ... [Pg.3]

CjA and C3S were discriminated in thin sections and powders mounted in Hyrax, asynthetic resin with index of refraction" of approximately 1.710. [Pg.4]

THIN SECTION Transmitted Light POLISHED SECTION Reflected Light POWDER MOUNTS Transmitted Light... [Pg.19]

Methods of raw feed examination utilizing powder mounts and thin sections are discussed in detail in Chapter 10. [Pg.20]

Understanding what one observes in powder mount, polished section, or thin section requires an appreciation of not only the cement manufacturing process but also the varied effects of light as it passes through or is reflected from crystals and amorphous materials. Formal training or extensive experience in microscopy is required. For example, when viewing crushed clinker in cross-polarized light in refractive-index oil on a microscope slide or a thin section, one must be aware that the interference colors are dependent mainly on four factors ... [Pg.29]

Ono s method and theory of kiln control were introduced to the Western world by Mau (1975). In that same year Ono conducted a seminar for North American cement-company personnel in Hawaii, where he taught the details of his theories and method of kiln control with powder-mount microscopy. The dissemination of Ono s technique to the Western world was largely due to this seminar. Since that time Ono s theories and method of clinker interpretation have been subjects of research in laboratories of many North American cement companies, the Portland Cement Association, and in Europe. Mau (1979) reported on the routine application of the Ono technique in Hawaii and strongly supported Ono s Method and theories, stressing their use to control burning temperature. [Pg.44]

Ono s method of cement kiln evaluation is based on observations of clinker or cement powder mounted in a liquid medium on a glass microscope slide. A polar ized-light microscope (the so called petrographic microscope) is an absolute necessity, and magniflca tions at approximately 400X are recommended. To determine the parameters of the kiln conditions in Ono s method as described in 1995, cement or clinker powder is sieved through a 100 pm screen (approxl mately U.S. Sieve No. 140), and a powder mount is prepared with a liquid of refractive index in the range of 1.705 to 1.715. The principal value of Ono s tech nique is that it can be employed by a competent, well trained microscopist on a small sample of clinker... [Pg.46]

The above list indicates sole emphasis on silicate characteristics observed in powder mounts. However, as Ono recommends, data from other microscopical techniques, such as polished section and thin section, can be routinely used in a corroborative manner. A schematic temperature-time curve and the relationships between the silicates and burning conditions are given in Figure 6-1 and Table 6-1, respectively. [Pg.46]

Photograph 6-1 One s method for apparent birefringence of alite in powder mount. Crystal length-to-width ratio = approximately 2 1. Ono measures particle width. Other observers, the present writer included, measure crystal width. (S A6616)... [Pg.48]

Photograph 6-4 Clear to faint yellow, round belite crystals in powder mount (44- to 75-pm fraction). Fast to moderately fast cooling. Coal- and coke-fired, dry-process kiln, 45 MPa. (S A6619)... [Pg.49]

Successful application of Ono s theories and tech niques in routine clinker production and in kiln start up operations is recorded by Prout (1979) with powder mounts and polished sections providing essential data. Prout strongly asserts that application of the Ono tech nique should be more qualitative than quantitative and that the data should he interpreted relatively for optimum benefit (Prout, oral communication, 1984). Furthermore, Prout used the predicted strength as an Index Number for relative comparison, a procedure with which the present writer is in complete agreement. [Pg.53]

One of the principal difficulties in the determination of apparent birefringence by powder mount is finding proper crystals, those with relatively bright interference colors and length to width ratios of approximately two. Extreme difficulty in satisfying the ratio requirement may, in itself, be indicative of burning conditions such that the desired crystal development was inhibited. [Pg.55]

Pennell (1987) discussed the differences between alite birefringences determined with thin sections (the present author s data) and powder mounts, illustrating the fact that the latter determination was not accurate, but concluding that the values may be tolerable for correlation purposes. [Pg.55]

The problem of measurement of crystal thickness (t) for the determination of alite birefringence in powder mounts has been the subject of much discussion. Prout (oral communication, 1984) finds that the thick ness can be approximated by the equation (length + width)/2, giving a reasonable apparent birefringence. [Pg.55]

Determination of alite birefringence in powder mount is subject to an error of approximately 0.0006 and that a petrographers rule of crystal width being equal to 4/3 crystal thickness is not valid as a short cut. [Pg.56]

Mor and Perez (1994) presented a critical evaluation of Ono s method (powder mount only) using laboratory heating stages, concluding that the alite size and alite birefringence did not correlate. Correlation was said to be much better with regard to belite size and color. The correspondence between laboratory and industrial kiln microscopy was seriously questioned and differences in environmental conditions, mainly atmospheric composition, were alleged to be responsible. [Pg.57]

Bruggemann (1988), using the linear traverse technique for phase abundance, demonstrated that small, lattice defective, alite crystals produced in kilns with steep temperature profiles and short residence times improve grindability and cement quality. Ono s method, utilizing only a few crystals in a powder mount, was said to give doubtful results. ... [Pg.57]

Photograph 7-74 Prismatic alkali aluminate crystals in crushed clinker powder mount. High maximum temperature, long burning time, slow heating rate, moderately quick to moderately slow cooling rate. Gas- and coal-fired, wet-process kiln, 500 tons/day. (S A6692)... [Pg.107]


See other pages where Powder mounting is mentioned: [Pg.129]    [Pg.101]    [Pg.105]    [Pg.97]    [Pg.290]    [Pg.2265]    [Pg.20]    [Pg.2248]    [Pg.23]    [Pg.160]    [Pg.176]    [Pg.3]    [Pg.8]    [Pg.15]    [Pg.27]    [Pg.31]    [Pg.39]    [Pg.47]    [Pg.47]    [Pg.47]    [Pg.49]    [Pg.51]    [Pg.52]    [Pg.52]    [Pg.53]    [Pg.55]    [Pg.61]    [Pg.128]   


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