未知题型 根据能量守恒定律,各项能量之间的平衡关系一般可表示为According to the law of conservation of energy, the equilibrium relationship between various energies can generally be expressed as: 当进入系统的能量 - 离开系统的能量=系统储存能量的变化 When the energy goes into the system - the energy goes out of the system = the change in the energy stored in the system.
未知题型 焊条直径的选择主要取决于焊件厚度、接头形式,焊缝位置及焊接层次等因素()
未知题型 因病、事请假须填写请假单,由部门主管及上级领导审批通过,报人资部备案()