无论是暂时性中毒后的再生,还是高温烧积炭后的再生,均不会引起固体催化剂结构的损伤,活性也不会下降。
参考答案:错
下列运算正确的是( )
A.a2•a3=a6
B.a5+a5=a10
C.a6÷a2=a3
D.(a3)2=a6
Applications put computers to practical business (67) , but below the (68) it’s the heart of an operating system-the kernel-that provides the technical wizardry to juggle multiple program, connect to networks and store (69) . A traditional kernel provides all the functions for applications. The kernel (70) memory, I/0 devices and parcels out processor time. The kernel also supports security and fault (71) , which is the ability to recover automatically when parts of the system fail.
A.earth
B.bottom
C.table
D.surface