Float aging

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Name="Age in AGEU at Reference Date/Time" DataType="float" /> dtemDef OID="ID.ageu" SASFieldName="ageu" Name="Age Units" DataType="text" Length="6" />... 

The next problem was which trees to measure. Many tree ring sequences can be counted with an accuracy of about one year. Those which are not yet tied to modern sequences by overlapping ring patterns (said to be "floating"), can be dated in favorable cases with an accuracy of about 30 years by radiocarbon dating, depending on the age and the number of radiocarbon measurements which are made. 

During the colder periods, icebergs floated as far south as Portugal. One of these cold spells probably forced the Vikings out of Greenland. This period is known as the Little Ice Age, which lasted from about 1400 to 1900. 

Samples Studied. From British Seams. The suite of samples was collected and separated by the Coal Survey of the National Coal Board under the direction of Dr. G. W. Fenton, and the authors are indebted to Dr. Fenton for the gift of the samples. The suite consisted of the vitrinites, spore-rich exinites, fusinites and, in one case, the micrinite from five British coal seams of Carboniferous age together with the vitrinites from two coals of higher rank from which it was impracticable to separate the other macerals. The exinites were separated by float-and-sink methods from selected black durain bands, as also... 

The retina is the light-sensitive layer which forms a sort of carpet on the inside of the eye. It sometimes happens—especially in old age—that this carpet becomes detached from the eyeball and floats in the surrounding liquid. In the areas of detached retina vision is of course lost. 

Chalk consists almost entirely of calcite. formed principally by shallow-water accumulation of (l) calcareous tests of floating microorganisms and (2) comminuted remains of calcareous algae. The most widely distributed chalks are of Cretaceous age. as exemplified by the cliffs on both sides of the English Channel. Although an unallered deposit, chalk masses may contain nodules of chen and pyrite. 

A girl with floating harbor syndrome (short stature, delayed bone age, typical facies, and delayed speech development) received growth hormone from the age of 3.5 years for 14 months (83). At 6 years she developed an abnormal gait due to a tethered cord. 

Figure 9. ESCA spectra of pyrite after several aging and aeration treatments, reading from top to bottom dry ground, 20 d in distilled water, crusher outlet, floated at pH 4.5, and goethite FeO-OH. (Reproduced, with permission, from Ref. 17. Copyright 1981, Elsevier Sequoia.)...

Since the Bronze Age both natural ceramic raw materials and synthetic raw materials have been used. Today synthetic raw materials are referred to as industrial minerals or specialty chemicals. Natural raw materials are those to which only physical separations are performed (e.g., clay soils from which organic raw materials are floated, feldspar rock ground to a particular size distribution). With this classification, a description of common ceramic raw materials will be given in the next part of this chapter. 

Commercially deactivated FCC Beats of varying matrix types and containing a wide range of sodium were characterized by t-plot surface area (ASTM D4365-85) to determine the effect of Na on zeolite and matrix area stability. The Beats were also examined by electron microprobe (Cameca SX50) to determine the Na distribution within a catalyst particle. Some of the Beats were separated into eight age fractions based on a modified sink/float procedure described in the literature (13,14). Bach age fraction was analyzed by ICP, t-plot and zeolite unit cell size (ASTM D3942-91). 

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