Ⅱ. Listening skills Understanding Times and dates w: Oh, look at the clock It's 5: 15. I'll be late for Jennifer's birthday party! I was supposed to leave at 5 o'clock M: Don't worry! You still have some time. The clock is twenty minutes fast Q What time is it now?
Sec. 5-1 Force Laws Sec. 5-2 Tension and normal forces Sec. 5-3 Friction forces Sec. 5-4 The dynamics of uniform circular motion Sec. 5-5 Time-dependent force Sec. 5-6 Noninertial frames and pseudoforces Sec. 5-7 Limitations of Newton’s law
Being aimed to developing intermetallic base structural materials to be worked at above 1000℃, a systematic investigation has been performed of the fundamental crystallographic structure, phase constitution map, density-composition dependence, oxidation resistance and general mechanical behaviour for the ternary intermetallic alloys in the Nb-Ti-Al system. Promissing results have been obtained at the initial stage in the current program. The 1100℃ high temperature strength at the strain rate of 10-2/s and 10-5/s for the ternary compound NbTiAl3 (γ1) base alloys are generally much higher than that of the binary compound TiAl (γ), especially in the γ1 + α2 phase region, it is as high as twice as that of TiAl. The densities are 4.1-4.79g/cm3, depending on relative amount of the intermetallics involved and the density difference between the intermetallics. The oxidation resistance at th