在DCS中,当调节器为手动时,SV值始终()PV值。A.大于 B.小于 C.等于 D

题型:单项选择题

问题:

在DCS中,当调节器为手动时,SV值始终()PV值。

A.大于

B.小于

C.等于

D.无法确定

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如图,△ABC中,AB=AC,∠BAC=54°,∠BAC的平分线与AB的垂直平分线交于点O,将∠C沿EF(E在BC上,F在AC上)折叠,点C与点O恰好重合,则∠OEC为______度.

题型:单项选择题

下列关于遗传密码的叙述中正确的是

A.遗传密码只代表氨基酸

B.一个密码子可代表不只一种氨基酸

C.每种氨基酸只有一个密码子

D.每个tRNA的反密码子只能识别一个密码子

E.密码子第3位碱基与反密码子配对可不严格互补

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我国的对未成年 * * 益的保障以()为基础。

A.未成年人保护法

B.劳动法

C.民法

D.婚姻法

E.宪法

题型:单项选择题

Scientists around the world are racing to learn how to rapidly diagnose, treat and stop the spread of a new, deadly disease. SARS — Severe Acute Respiratory Syndrome — was (1) for the first time in February 2003 in Hanoi, (2) since then has infected more than 1,600 people in 15 countries, killing 63. At this (3) , there are more questions than answers surrounding the disease.

Symptoms start (4) a fever over 100.4 degrees F, chills, headache or body (5) . Within a week, the patient has a dry cough, which might (6) to shortness of breath. In 10% to 200% of cases, patients require (7) ventilation to breathe. About 3.5% die from the disease. Symptoms (8) begin in two to seven days, but some reports suggest it (9) take as long as 10 days. Scientists are close to (10) a lab test to diagnose SARS. In the meantime, it is diagnosed by its symptoms. There is no evidence (11) antibiotics or anti-viral medicines help, (12) doctors can offer only supportive care. Patients with SARS are kept in isolation to reduce the risk of (13) . Scientists aren’t sure yet, but some researchers think it’s a (14) discovered coronavirus, the family of viruses that cause some common colds.

Most cases appear to have been passed (15) droplets expelled when infected patients cough or sneeze. Family members of infected people and medical workers who care for them have been most likely to (16) the illness. But recent developments in Hong Kong suggest that the (17) might spread through air, or that the virus might (18) for two to three hours on doorknobs or other (19) Health experts say it is (20) , though, that sharing an elevator briefly with an infected person would be enough to pass the virus.

5()

A.hurt

B.sore

C.aches

D.feelings

题型:单项选择题

SLZ-2A综合录井仪在注样调试时计算机不能控制()。

A、抽气泵

B、前置电路

C、分析周期

D、气测电路

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