Fuelinjectorsusedinheavyfueloilsystemsareusuallyprovidedwithcoolingtoreduce().
A. coldcorrosionofthenozzles
B. fuelviscosityforbetteratomization
C. carbonaccumulationonthenozzles
D. fueldetonationinthecylinders
Whichofthefollowingstatementsconcerningfire-tubeboilersiscorrect?()
A. Combustiongasesflowthroughthetubes
B. Flamesimpingeonthetubes
Combustionoccursinthetubes
D. Waterflowsthroughthetubes
引起肌肉兴奋一收缩耦联的最关键因素是什么?()
ATP酶的活性
B. 肌钙蛋白的状态
C. Na内流的速度
D. 横桥的运动
E. 胞浆内Ca的浓度
Asetofclampsthatarelatchedontothedrillpipetoallowthedrillertoraiseorlowerthedrillstringoutoforintotheholearethe().
A. lifts
B. collars
C. elevators
D. clamps