下列关于袋式除尘器的说法，哪项是错误的
A．清洁滤布的压力损失一般比使用中的滤料层压力损失低得多
B．压力损失与过滤风速有关
C．采用针网滤料时，可采用机械振动清灰
D．采用涤纶纤维滤料时，袋式除尘器使用于排气温度为140℃的场合
参考答案：C
解析： 《三版教材》：针网滤料具有深度过滤作用，机械振动清灰方式适用于以表面过滤为主的滤袋，对深度过滤的粉尘清灰几乎没有效果。
| Texans have bursting pride and love attention. They also have a thick streak of short- sighted greed and, even by American standards, a busted disposition to violence. When they hear this sort of criticism they usually ascribe it to the ignorance and jealousy of stuffy Yankees who have not spent enough time in the state to understand it. For such avowedly robust people they are surprisingly sensitive. They hated Edna Ferber’s novel Giant, which scourged Texan vulgarity, racism and the mores of millionaires, but they bought it in great quantities and packed cinemas to see the film. They would rather be talked about than not, and if you do not talk about them they do it for you. In claiming special qualities for themselves, Texans have had to become reconciled to the fact that a large number of them are not native. In the last century "Gone to Texas" was a commonplace graffito daubed on barns in other states, and in recent years "Gone to Texas" has, figuratively, been written on the front doors of millions of Americans and also Mexicans. In the early 1980s newcomers accounted for nearly two-thirds of the state’s population increase. But Texans do not believe they are being diluted. They maintain that Texanhood, or Texianism, is a matter of attitude and that Texanic qualities exist in abundance in many Americans, regardless of their birthplace: it is when these people are planted in Texas, and nourished by its atmosphere, that they flower like true Texans. A man may not be born in Texas, which is unfortunate; but he can be born to be Texan. Many Alaskans are urban, young and raising families, here for a while, and trying to make money before moving to somewhere warmer. But many are staying. While most remain in Anchorage and other centers, some set out to build a cabin in the wilderness and live by hunting, trapping and fishing, learning how to skin a muskrat and moose, how to survive terrible weather, how to be truly in tune with the land, taking pleasure in great silence and unpeopled immensity. To settle the frontier the state has a homesteading program, based on the federal Homestead Act of 1864, which was a key event in the opening up of the American west. Hundreds of Alaskans are awarded parcels of wilderness land in an annual lottery and undertake to invest sweat equity, to build a home within three years and clear and cultivate the land within five. Alaskans love reading about Alaska, and two of the most popular books are a manual on log cabin building and a collection of tales about grizzly bears, of which Alaska is a phold. Log cabin life is for the stout-hearted few with the springs of adventure p in them, and these wilderness Alaskans are remarkable. Some are refugees of one kind or another. Several hundred are Vietnam veterans, tortured by their experiences of war and unable to fit into normal urban life, seeking solace in the wilds. |
Which of the following statements can best describe Texans
A．They are aggressively self-confident of their wisdom.
B．They are brutally crude in making a living for themselves.
C．They are blindly allergic to negative comments on their weakness.
D．They are openly and crudely thin-skinned about discriminations against them.