问题 单项选择题

中子水分仪测量时,热中子云的密度主要取决于氢的含量,土壤中几乎所有的氢都存在于水中,所以土壤中水分的含量与()数量成正比。热中子数量可由热中子()测量获得,根据热中子的计数率与土壤含水量的线性关系,由计数率得出含水量的数值。

A、中子;捕获器

B、快速中子;捕集阱

C、热中子;探测器

D、质子;调节器

答案

参考答案:C

单项选择题 A1型题
单项选择题

Another critical factor that plays a part in susceptibility to colds is age. A study done by the University of Michigan School of Public Health revealed particulars that seem to hold true for the general population. Infants are the most cold-ridden group, averaging more than six colds in their first year. Boys have more colds than girls up to age three. After the age of three, girls are more susceptible than boys, and teenage girls average three colds a year to boys’ two.
The general incidence of colds continues to decline into maturity. Elderly people who are in good health have as few as one or two colds annually. One exception is found among people in their twenties, especially women, who show a rise in cold infections, because people in this age group are most likely to have young children. Adults who delay having children until their thirties and forties experience the same sudden increase in cold infections.
The study also found that economics plays an important role. As income increases, the frequency at which colds are reported in the family decreases. Families with the lowest income suffer about a third more colds than families at the upper end. Lower income generally forces people to live in more cramped quarters than those typically occupied by wealthier people, and crowding increases the opportunities for the cold virus to travel from person to person. Low income may also adversely influence diet. The degree to which poor nutrition affects susceptibility to colds is not yet clearly established, but an inadequate diet is suspected of lowering resistance generally.

Which of the following most probably means the word "particulars" underlined in Paragraph 1

A.Minor errors.

B.Specific facts.

C.Small distinctions.

D.Individual people.