下列关于面酱中灰分的测定中,说法正确的是( )。A.样品必须完全碳化后,才可移入马

题型:多项选择题

问题:

下列关于面酱中灰分的测定中,说法正确的是( )。

A.样品必须完全碳化后,才可移入马弗炉中进行灰化

B.试样一定要灼烧至灰白色为止

C.同一样品的两次测定结果之差不得超过平均值的2%

D.灰化温度不超过600℃,否则氯、钾、钠易挥发而减重

考点:食品检验工初级食品检验工初级
题型:多项选择题

对实验现象的观察和分析有助于我们获得化学知识并学会科学探究的方法。下列对实验现象分析正确的是[ ]

A.碳酸盐与硫酸反应放出气体,所以与硫酸反应放出气体的物质一定是碳酸盐

B.硝酸钾溶于水会使溶液温度降低,所以能使溶液温度降低的物质一定是硝酸钾

C.淀粉遇到碘水呈现蓝色,所以与碘水作用呈现蓝色的物质中一定含有淀粉

D.氯化钠能使溶液的凝固点降低,所以能使溶液的凝固点降低的物质一定是氯化钠

题型:多项选择题

当肝显像已显示肝内占位病变时,一般来说下列哪一点是不正确的()

A.可定位诊断

B.可定性诊断

C.可显示占位病变大小

D.可了解占位病变单发或多发

E.可显示占位病变的形态

题型:多项选择题

基于专业技术人员能否对观察对象进行控制,观察调查可以分为()。

A.结构性观察

B.无结构性观察

C.实验观察

D.非实验观察

题型:多项选择题

龙虾在受到外界刺激后15毫秒内就可做出快速反应依靠的是()

A.化学耦联

B.电耦联

C.代谢耦联

D.桥粒

E.黏着斑

题型:多项选择题

Stress is with us all the time. It comes from mental or emotional activity as well as physical activity. It is unique and personal to each of us. So personal, in fact, that what may be relaxing to one person may be stressful to another. For example, if you’’re a busy executive who likes to keep occupied all of the time, "taking it easy" at the beach on a beautiful day may be extremely frustrating, nonproductive, and upsetting. You may be emotionally distressed from "doing nothing." Too much emotional stress can cause physical illnesses such as high blood pressure, ulcers, or even heart disease. Physical stress from work or exercise is not likely to cause such ailments. The truth is that physical exercise can help you to relax and to better handle your mental or emotional stress.

Which of the following people would find "taking it easy" stressful

A.Construction workers.

B.Business executives.

C.Farm workers.

D.Truck drivers.

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