Excel ranges

Because of its excellent range of properties and reliability, poly(fluoroalkoxyphosphazene) elastomers are used as seals, gaskets, and shock mounts in demanding military, aerospace, petroleum and industrial applications. In addition, applications under development for this elastomer include fuel hoses for artlc use, coated fabrics for protective clothing, sealants, coatings and medical devices. 

The alkylating agent, usually an iodoalkane is added in hexamethylphosphoric triamide. Chlorides or bromides can also be used, preferably in the presence of 10 mol% tetrabutylam-monium iodide5,6. The diastereomeric ratio of the crude alkylation products 2/3 is usually excellent, ranging from 95 5 to 99.5 0.5 (see Table 13 and references 17 and 19). The alkylation products are most conveniently purified by recrystallization which removes the small amount of the minor diastereomer. 

The sulfur percentages of 0.02 weight-percent or less in the shale oil diesel fuels would permit these fuels to be classed as low-sulfur diesel fuels. Nitrogen percentages were low, ranging from 141 to 202 parts per million (ppm). Cetane indexes, calculated by ASTM method D-976 (7j, were excellent, ranging from 48 to 56. 

The optically active y-nitro ketone products of type 8 were obtained with increased enantioselectivities of up to 76% ee. The yields remained in a medium to excellent range of up to 99%, and diastereomeric ratio of up to 98.5 1.5 were observed. So far, however, the long reaction time of 2-8 d represents a limitation which has to be further improved. A representative example is shown in Scheme 6. 

In this chapter, the development of a thermosetting adhesive from soda bagasse lignin is described. The research has concentrated on the development of interior-grade adhesives for particleboard. The local market for exterior boards is smaller than that for the interior panels, and adhesives for exterior boards are already covered by an excellent range of tannin-based adhesives. 

These include toxicity, flammability, explosivity, stratospheric ozone depletion, atmospheric ozone production and global warming potential.[27] Bearing all these criteria in mind, the alternative solvents mentioned above provide an excellent range of properties with considerable potential. 

Enantiomeric ratios are generally excellent, ranging approximately from 90 10 to > 98 2 using these procedures. The rationale for face selectivity is not fully understood, since the mechanism appears to involve a homochiral dimer [BlNOL]2Ti2X2.i2o Three examples applied to functionahzed aldehydes are illustrated in the formation of 382, 384, and 387 (Scheme 5.2.84).121... 

Only one method was located for analysis of tissue samples. The method used HPLC/UV to analyze bovine kidney, muscle/fat, and liver samples for RDX, but it could be used to analyze human tissues (Army 1981 a). Optimal sample preparation methods varied slightly for the different tissues, as did detection limits and precision. In general, the detection limit was in the low ppb and recovery was excellent (range of 87.7-102.9). Precision ranged from 7 to 16% CV. The primary problem with analysis of tissue using this method is the variation in selectivity. Minor differences in sample extraction and contamination from unknown sources can create interferences that drastically affect interpretation of results and may also adversely affect the sensitivity. 

In a continuation of his studies on asymmetric P-lactam synthesis, Evans [42] utilized a,P-epoxyaldehydes 49a and 49b, prepared in two steps from achiral allylic alcohols via Sharpless asymmetric epoxidation and Swern oxidation, as chiral glyoxal synthons for the ketene-imine cycloaddition. Diastereosel-ection was excellent, ranging from 90 10 to 97 3 with overall yield of 50 up to 84% (for Schiff base formation and cycloaddition) after recrystallization or chromatographic purification of the major diastereomer. The sense of asymmetric induction correlated with that obtained in the analogous glyceraldehyde reaction, as established by periodic acid cleavage to aldehydes 51. 

Liquid thermometers are the most common instrument employed to measure atmospheric temperature. They have an excellent range and can measure temperatures from as low as -200 °C to above 600 C. Similarly to gas thermometers, they are based on the dilation properties of liquids when subject to changes in temperature. Many liquids have been used to measure temperature including water, alcohols, mercury, paraffins, and aromatics. 

Abstract A wide variety of natural fibers can be applied as reinforcement or fillers in composites. Bast fibers, such as fiax and hemp, have a long history of cultivation and use. They are characterized by low weight and excellent range of mechanical properties. The properties of bast fibers are influenced by conditions of cultivation, retting, and processing. Pretreatment and surface modification of bast fibers is conducted for optimization of the interfacial characteristics between fiber and matrix as well as improvement of their mechanical properties. Application of bast fibers as reinforcement to replace the glass fibers to composite manufacture brings positive environmental benefits. 

Thanks to the 20-kWh lithium-ion battery (shown in Figure 10.19), the Spark EV is expected to provide an excellent range performance in its segment. The Chevrolet Spark EV will be the first EV to offer SAE Combo DC fast charging capability enables this EV to reach 80% battery charge in just 20 min. A full standard recharge takes 7 h on a 240-V charger. 

Dielectric properties are excellent, ranging 3.3-3.5 at 60 Hz. Polyimides also have a low coefficient of thermal expansion, 28-34xl0" in./ in.F°. Use of fillers, e.g., glass, graphite and asbestos, reduces dimensional changes to even lower levels. 

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