Maceral analyses

The quantitative maceral analyses presented above are used to demonstrate petrographic continuity of coals from place to place. The examples used were selected to emphasize different aspects of regional and local situations. Problems encountered in the Houtzdale quadrangle illustrate that some measure of continuity can be established locally in spite of rapid changes in thickness and character of the coal beds involved. 

Duncan G. Murchison Could Mr. Koppe tell us how many points were counted in the maceral analyses quoted In the absence of any deviations on the figures, it would seem that to allow a significant difference between 2.6 and 4.2%, for example, the number counted would have to be very high. 

Mr. Koppe 500 points were counted from pellets of —30 mesh coal for each layer. Thus, the maceral analyses for total coal beds are variable. In some profiles, as few as 1500 points were used in others 4000 or more. On the total bed basis, I think the difference quoted is significant. 

These samples were studied by chemical and microscopic methods. Chemical data include moisture, ash, volatile matter, total carbon, and hydrogen. Microscopic data include reflectance measurements on samples from both cores and maceral analyses of core DDH-B. 

Maceral analyses—i.e., coal constituent analyses—were made on polished pellets of the coal samples from 9, 7, and 6 feet from the sill contact. A Leitz Ortholux microscope at approximately 750X magnification was used. At a distance of less than 6 feet from the sill contact it was impossible to distinguish any specific macerals in the coal samples. At 6 feet it was possible to distinguish the macerals, and a ratio of reactives to inerts of 20 80% was found. At 9 feet there was an approximate ratio of 70 30% of reactives to inerts. The bulk of the increase is caused by carbonization of other macerals. 

Table I. Analytical and Maceral Analyses of Demineralized Coals...

Maceral Analyses. Maceral analyses were carried out under the microscope in reflected and fluorescent (blue-light excitation) light at magnifications of x 250 and X 500. A point-count method counting 500 points was used. This gives an accuracy of 2-3% for each maceral. 

Results of the maceral analyses for the five samples of different lithotypes are presented in Table IV. One observes a general decrease in the concentrations of humodetrinite and liptinite and an increase in... 

Apart from the exinite and micrinite, all the other coal material in this section is vitrinite and would be counted as such in a maceral analysis. These macerals were identified not only from their form, which is often characteristic, but by direct comparison of the light-microscope picture of the facet from which the ultrathin section was cut (I). By using this technique, each maceral occurrence of sufficient size could be positively identified. 

Gross calorific value Hardgrove grindability Majcr and minor elements Proximate analysis Reflectance of organic matter Total moisture Trace elements Ultimate analysis Volatile matta-Maceral analysis... 

The most widely used petrographic analyses of coal are maceral analysis and vitrinite reflectance analysis. Both are performed on representative samples ground to < 1 mm in size and embedded in resin. The polished surfaces are then examined under a white reflected light microscope. 

A mixture of several coals—a so-called blend—can only be clearly identified from a maceral analysis. 

Although not belonging to the primary scope of a maceral analysis, the nature of the ash fraction, as well as special minerals, can already be identified under the light microscope, providing hints for de-ashing or temperature history caused by thermal decay. 

The deletion of pelX and of the five major pel genes from the E. chrysanthemi chromosome failed to totally eliminate the capadty for tissue maceration (16). Analysis of the macerated tissue by electrofocusing followed by an activity detection, revealed the presence of a new set of pectate lyases (up to 5 forms). Because of their low activity in synthetic medium, they were described as secondary pectinases. The gene of one secondary endo-pectate lyases, PelL, has been characterized in two E. chrysanthemi strains. The pelL gene of E. 

Macerated plant material is homogenized with acetone-water (3 1, v/v) and vacuum Altered, and the Alttate is adjusted to constant volume. A portion of the Altrate is further Altered through a syringe Alter and diluted 1 1 with an isotopically labeled internal standard solution for analysis by electrospray LC/MS/MS. 

Macerated plant material is homogenized with a mixture of methanol and 1.2N hydrochloric acid (HCl) in water (4 1, v/v) and then with methanol. An internal standard solution is added to the filtrate and the filtrate is adjusted to a constant volume. A portion of the filtrate is rotary evaporated to dryness and hexane is added to the extract before a Florisil cleanup procedure is performed. The extract is dissolved in toluene for analysis by GC/MS in the negative chemical ionization (NCI) mode. 

The slopes of the regression lines for conversion yield against reactive macerals for the hot-rod and for the rotating autoclave modes of hydrogenation are shown by statistical analysis to be similar (compare Figures 9 and 10). This suggests that the relationship between total reactive macerals and coal reactivity as measured by conversion is not dependent on the conversion technique. 

Although most consumers appreciate the fieriness of chile, capsaicinoids are not perceived through odor or taste receptors but through the nociceptive pain receptors described earlier. The compounds in chile fruit that create the flavor and aroma are produced in the fruit wall. Buttery et al. [90] generated vacuum steam distilled oil from green bell pepper macerate, with well over 40 peaks on subsequent GC/MS analysis. Of these peaks, the major flavor compound associated with bell pepper aroma was 2-methoxy-3-isobutylpyrazine (Fig. 8.1). They also reported several monoterpenoids in abundance, limonene, trans- 3-ocimene, and linalool as well as other aliphatic aldehydes and ketones. The flavor composition of dried red bell pepper powder (sweet paprika) extracted with ether identified 44 key peaks by GC/MS [91]. In these dried samples the key compounds were P-ionone and several furanones. The post-harvest processing and the different fruit maturities as well as possible varietal differences are all causes for the different aromatic profiles. 

In Curie-point Py-LVMS studies of maceral concentrates (22). vitrinitic moieties were shown to be the main source of the hydroxy aromatic components. Thus, the hydroxy aromatic signals observed in Figure 2d appear to be primarily derived from vitrinite-like components by means of pyrolytic processes. Presumably, therefore, the "nonmobile phase", rather than the "mobile phase , is the main source of the phenols observed in TG/MS and Py-MS studies of Pittsburgh 8 coal (9,16). Further support for this conjecture comes from the observation that phenolic products are also observed in Py-MS analysis of pyridine extracts of Pittsburgh 8 coal known to contain colloidal matter whereas the corresponding tetrahydrofuran extracts, free of colloidal material, produced no phenols (21). 

By applying this analysis at discrete 10 K temperature intervals to the NMR thermal analysis data for the 102 coals (subdivided into brown coals (<75% C), lower rank (80-85% C) and higher rank (85-90% C) bituminous coals), regression coefficients could be obtained as functions of temperature and hence the average 2T of the three maceral groups were generated (Figures 3-... 

Support was provided under the National Energy Research, Development and Demonstration Program (NERDDP). T.P. Maher of the Joint Coal Board provided coal specimens and expert advice. P.J. Redllch (Monash University) supplied brown coals and extracted residues. Maceral concentrates were provided by N. Lockhart, C. Davies, M. Shlbaoka, N. Ng and A. Cook. N. Thomas and Z. Lauks performed most of the thermal analysis experiments. 

Rudnitskaya, A., Schmidtke, b. M., Delgadillo, b, begin. A., and ScoUary, G. (2009b). Study of the influence of micro-oxygenation and oak chip maceration on wine composition using an electronic tongue and chemical analysis. Anal. Chim. Acta 642(1-2), 235-245. 

Separating the three macerals from the dull coal was difficult. The petro-graphical purity of the exinite is 86% and that of the micrinite 94%. For both macerals, vitrinite is the main impurity. Since the vitrinite has a petrographi-cal purity of 99%, it is not difficult to calculate the values for the pure exinite and pure micrinite from the experimental data on the highly enriched maceral fractions. All values reported in the tables are corrected ones. Table I summarizes the results of elementary analysis (maf) and the percentage of volatile matter. 

The Car values for the three macerals can be obtained by x-ray structural analysis (5). From the mean lamellae diameter N values can be calculated which principally measure the mean number of atoms in a hexagonal network and in the same plane. Therefore, N can represent either only the Car atoms of the cluster or the Car atoms and also atoms like C.i, O, N, and S which are directly linked to the aromatic cluster. In the first case, N=C r ,i,x) and in the second case N=C ,r + X, X being the number of substitution places (C .r(>nliM) ) except direct bonds. 

From aromaticity and elementary analysis the total number of rings per mean unit (R) can be derived. The number of nonaromatic rings is then given by R r = R — R.r and includes alicyclic and heterocyclic rings. If all hetero atoms were to form a ring, there could be a maximum of — 0.8 such rings per unit in all three macerals. Limits for the number of alicyclic rings per unit... 

The absorption curves given by coal macerals approached the horizontal (magnetic field strength) axis more slowly than a Gaussian distribution curve. Shape analysis (16) showed that over much of the curve, the form closely approximated a Lorentzian distribution curve, but both positive and negative deviations were found in the wings of the curves (that is, in various examples, the curves approached the axis either somewhat more or somewhat less rapidly... 

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