Detailed studies have been carried out on the distribution of organic functional groups and inorganic species in as-received (ar) and acid-washed (aw) brown coals using elemental analysis, energy dispersive X-ray analysis (SEM-EDX), X-ray photoelectron spectroscopy (XPS), and Time-of-flight−secondary ion mass spectrometry (TOF−SIMS). Surface concentrations of the various carbon groups, organic oxygen, and inorganic hydroxide were obtained using XPS, but oxygen from clay and quartz, if present, interfered with organic oxygen determinations for the coals. A comparison of ar and aw coals using XPS and SEM-EDX is provided in terms of inorganic and organic sulfur groups. Chloride in these coals is present mainly as acid extractable forms, but small amounts of chloride in the organic matrix were indicated by the elemental analysis of ultra low-ash coals. TOF−SIMS fragments from brown coals were indicative of polymers consisting mainly of single aromatic groups linked by hydrocarbons with carboxyl and phenol functional groups. Sulfur fragments were from inorganic sulfur, thiols, organo-sulfates, and S−N−organic species. Numerous fragments containing organically bound chloride were observed. Fragments of the inorganic species Na, Mg, Al, Si, K, Ca, Ti, Cr, Fe, Mn, Ni, Cu, and Ga were also observed. Environmentally undesirable species, particularly from organo-sulfur and organo-chloride groups in brown coal, are likely to emerge from processes that heat coal−water mixture.

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When cultures of Brachyspira hyodysenteriae were grown under a wide range of in vitro conditions, at least 1% of the cells formed spherical bodies different to the normal helical form. This percentage increased considerably in aging cultures or following their incubation in caramelized media. Spherical body formation was initiated from a terminal localized swelling of the outer sheath followed by a retraction of the protoplasmic cylinder into the resulting swollen vesicle. As this occurred, the periplasmic flagella seemed to unwind from the protoplasmic cylinder. Once retracted, the protoplasmic cylinder was found to be wrapped in an organized manner around the inner surface of the membrane of the swollen vesicle. Although most were 2-3 microm in diameter, some much larger spherical bodies (6-12 microm diameter) were occasionally seen, with a corresponding increase in the visible number of peripheral protoplasmic cylinder cross-sections. Spherical bodies from older cultures did not contain protoplasmic cylinders arranged around the periphery, but instead were characterized by the presence of a centrally located, electron-dense body c. 0.5-0.8 mum in diameter. Brachyspira hyodysenteriae spherical bodies differ in both their structural organization and probable method of formation from similar structures described in other spirochaete genera.