下列722型分光光度计的主要部件是()。A、光源:氘灯 B、接受元件:光电管 C、波

题型:多项选择题

问题:

下列722型分光光度计的主要部件是()。

A、光源:氘灯

B、接受元件:光电管

C、波长范围:200-800nm

D、光学系统:单光束,衍射光栅

考点:水环境监测工水环境监测工题库
题型:多项选择题

显示器按显示方式进行分类可分为()。

A.球面

B.纯平

C.CRT

D.LCD

题型:多项选择题

可发生心肌向心性肥大的疾病是()。

A.心肌炎

B.高血压病

C.二尖瓣关闭不全

D.甲亢

题型:多项选择题

当采用( )类灯具时,灯具的外露可导电部分应可靠接地。

A.Ⅰ
B.Ⅱ
C.Ⅲ
D.Ⅳ

题型:多项选择题

神经纤维上升相是指

A.去极化过程
B.超极化
C.去极化和反极化过程
D.极化
E.复极化过程

题型:多项选择题

Throughout the 19th century and into the 20th, citizens of the United States maintained a bias against big cities. Most lived on farms and in small towns and believed cities to be centres of (1) , crime, poverty and moral (2) Their distrust was caused, (3) , by a national ideology that (4) farming the greatest occupation and rural living (5) to urban living. This attitude (6) even as the number of urban dwellers increased and cities became an essential (7) of the national landscape. Gradually, economic reality overcame ideology. Thousands (8) the precarious (不稳定的) life on the farm for more secure and better paying jobs in the city. But when these people (9) from the countryside, they carried their fears and suspicions with them. These new urbanities, already convinced that cities were (10) with great problems, eagerly (11) the progressive reforms that promised to bring order out of the (12) of the city.

One of many reforms came (13) the area of public utilities. Water and sewerage systems were usually operated by (14) governments, but the gas and electric networks were privately owned. Reformers feared that the privately owned utility companies would (15) exorbitant (过渡的) rates for these essential services and (16) them only to people who could afford them. Some city and state governments responded by (17) the utility companies, but a number of cities began to supply these services themselves. (18) of these reforms argued that public ownership and regulation would (19) widespread access to these utilities and guarantee a (20) price.

(10)()

A.overwhelmed

B.overflowed

C.overtaken

D.preoccupied

更多题库