Relative test

Inhalation of diesel fuel aerosol 4 hours/day, 2 days/week, for 13 weeks at concentrations up to 1,500 mg/m did not induce relative testes weight changes nor histopathological changes in the reproductive organs of rats (Lock et al. 1984). 

Marked and significant reductions in absolute and relative testes weight and atrophy of testicular germinal epithelium were observed in male rats exposed to 700 ppm 2-hexanone for 11 weeks (Katz et al. 1980). 

Table 14.3 contains comparative hardness values for five hardness scales including the classical Mohs scale, which ranges from the force necessary to indent talc given a value of 1 to that needed to scratch diamond given a Mohs value of 10. In the field, a number of relative tests have been developed to measure relative hardness. The easiest test for scratch hardness is to simply see how hard you have to push your fingernail into a material to indent it. A more reliable approach involves scratching the material with pencils of specified hardness (ASTM-D-3363) and noting the pencil hardness necessary to indent the material. 

When the results of the yellow limestone clay and the red field clay analyses were processed by the potstat routine (10), an average of data from the two clays yielded a pattern that matched (except for sodium) the analytical pattern of pottery made of a mix of the two clays. In the first case, the two raw clays were simply ground and analyzed separately in the second case, the two clays were mixed in a water bath, sand and Dead Sea salt were added, a vessel was formed, dried, and fired, and this finished product was analyzed. The sand temper did not contribute significantly to the relative test element concentrations, but the salt addition did, of course, raise the sodium concentration. These results are graphed in Figure 2. 

Rat (Sprague- Dawley) 5 d ppd 6-10 1x/d (GO) 100 1000 (reduced absolute and relative testes weight and number of Sertoli cells) Dostal et al. 1988... 

The results of such tests are most useful for determining differences in stability among columns from various manufacturers (ie., they are good relative tests). However, these tests should not be considered absolute measures of column stability since their relationship to real-life use conditions is not known. 

Over the last 30 years, we have observed 46 cases of professional dermatitis artefacta. These cases are certainly true simulations because the suspicion, suggested by the combination of work problems , the particular morphology of the lesions and the repeated negative findings of all the relative tests, was confirmed by confessions obtained from all the patients after repeated, confidential and informal discussions. 

Fig. 19.8 Through-plane surface resistance (relative test method) results of HT-PEM bipolar plates with different configurations where BPP4 is mature material while PPS and PVDF are development materials. The data show...

While the macroscopic mechanisms observed appear similar between the different oxidants, the overall aggressiveness of the oxidants at the test eonditions is observed to vary notieeably. Relative test lifetimes for the three diffo ent oxidants at the test eonditions vary by a factor of three. While some of this difference can be explained based on the relative oxidative aggressiveness of the different oxidants, the relative test hfetimes suggest that other more subtle mechanisms may be at play. 

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