工作面若采用除尘风机时,工作面安装瓦斯自动检测报警断电装置,保证除尘风机的吸风侧瓦斯浓度不超过()。
A、1.0%
B、0.5%
C、1.5%
D、0.1%
参考答案:A
把煤隔绝空气加强热,不能得到下列物质中的( )
A.焦炭
B.水煤气
C.煤焦油
D.焦炉气
Future Computer Trends: The components of a PC will be built into the (6) and large plasma or electroluminescent flat panel display hanging on a partition wall will act as both a (7) and videophone display.
A. desk B. monitor C. built D. mouse-driven
A high resolution, touch sensitive LCD (8) into desktop will allow pan-based pointing and data input. In the home, meanwhile, computers will become as ubiquitous as TVs.Computer interfaces will be far friendlier than (9) graphical user interfaces (GUI) of today. Computers will use "human interfaces" based on multimedia.RISC microprocessors will finally obliterate the ever thinning gap between workstations and PCs. Similar advances in nonvolatile flash memory will lead to the replacement of magnetic (10) disks with electronic "silicon disks".