Weathering micro-scale

Although less energetically efficient than the oxidation of hydrogen sulphide (Fig. 8.4), the oxidation of metal sulphides could potentially support chemo-synthesis at seafloor massive sulphide deposits long after hydrothermal activity had ceased, even in well-buffered seawater (Eberhard etal., 1995 Juniper Tebo, 1995). Newly formed sulphide deposits are rapidly subjected to oxidation upon contact with ambient seawater, and some show micro-scale weathering features (e.g. etch pits on mineral surfaces Verati etal., 1999),... 

The meso- and micro-scale synoptic systems which form rainstorm occur and develop along the large-scale circumfluence. The post studies were mainly describing the large-scale and meso-scale systems (Tao et al., 1998). Therefore, it is still difficult to explain the heavy rain event with meso-P scale weather systems with the existing mesoscale dynamical theories. 

Mineral standards were hand crushed to -1/4 inch, then ground to a fine powder in a ball mill (alumina elements) or Bleuler Model 526/LFS678 puck mill. The resultant powder was aerodynamically classified in a Bahco Model 6000 micro particle classifier and the finest fraction ( 18 throttle) was collected. A size criterion of 90% or more by weight of particles 5 micron and smaller in diameter was used for the mineral standards. Sizes were verified by Coulter Counter. Duplicate 13 mm KBr pellets were prepared and the spectra were weight-scaled by techniques similar to those reported by Painter (3) and Elliot (4). With one exception, all the mineral standard spectra were averages of spectra from duplicate pellets. The one exception was the iron sulfate spectrum, which was obtained as the difference spectrum by subtracting the spectrum of HCl-washed weathered pyrite from that of the weathered pyrite. A weight correction was applied to the difference spectrum. 

As noted for rubbers, micro tests using scaled-down indentor sizes and smaller loads are being used, and special mention should be made of the micro Vickers test [18]. which has been applied successfully to plastics (sec Ref. [19] for a review) in the determination of crystallization effects, anisotropy, the effect of weathering and heat aging, the study of polymer blends, etc. 

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