定量泵—液压缸系统如图题4-17所示。设液压缸机械效率ηM=0.95,容积效率ηV=0.94,无杆腔面积A=50cm2活塞运动速度为94cm/min,负载F=47.5×103N,液压缸回油腔压力p0=0,通过元件L的流量—压力差方程为△pL=4×104Q2(其中△p的单位为Pa,Q单位为L/min)。液压泵输出流量为7.93 L/min,当流量满足液压缸的工作要求后,多余流量在液压泵工作压力下经元件Y回油箱。设液压泵的容积效率ηBV=0.95,机械效率ηBM=0.90。试求:
A.appoint
B.utilize
C.employ
D.apply
A: how to
B; on what to
C; on how to
A、what’s more
B、at last
C、however
What did governments do to discourage the employment of older workers in the 1970s?
A.Offer early retirement to all employees.
B.Set specific age limits for employment.
C.Only employ younger trainees.
D.Offer incentives to businesses to take on younger employees.