问题 问答题 简答题

如何防止内墙乳胶漆起皮、脱落?

答案

参考答案:

首先,应选择耐水性优良的苯丙类、纯丙类内墙乳胶漆。

其次,产生这些现象与所用腻子的耐水性有密切关系,以前,由于内墙腻子的作用主要以填平墙体为准,没有什么具体要求,所以市场上内墙腻子大多采用化学浆糊与石膏粉调制,干性快,填刮不费力,易打磨,施工方便,但问题大多出现在这里,这些化学浆糊(也就是纤维素)遇水膨胀而逐步溶解于水中,由于体积增大和粘结强度下降,便造成了涂层起泡、开裂进而脱落。

解决方法为:采用白水泥与801胶水调制内墙腻子,填刮墙面,干透打磨后涂刷内墙乳胶漆,已脱皮的墙面应铲刮干净,用耐水腻子重新填平、涂装内墙乳胶漆。

阅读理解

     Everyone talks about the greenhouse effect(温室效应) and how our Earth and its climate are being affected. We can do a science experiment designed by some kids to show this effect and what is happening to the Earth.

      First prepare the following items:

     ●2 glass containers(容器) that need to be the same size and shape 

     ●1 gallon plastic bag

     ●4 cups of very cold water

     ●Ice cubes

     Fill each container with two cups of cold water. Add the same amount of ice cubes to each container. Then put one of the containers in the plastic bag and close it tight. Put both containers in the sun together and keep them there for at least an hour.

     At the end of one hour remove the container from the plastic bag and immediately check the temperature of the water. After you record this, find out the temperature of the water that is not covered.

     When you place the containers in direct sunlight, the air inside the bag becomes very warm. The heat filters (渗入) in but cannot escape so it stays in the closed plastic bag and increases the temperature. What if you leave that for two, three or four hours?

     Think about what is happening to the Earth. There are chemicals that are creating a type of plastic bag around the Earth. It causes our air to get warmer because of the heat from the sun being kept in this closed area.

     Think about your car in the hot summer. This is what happens when you leave your car outside all day. This greenhouse effect has caused your car to be so hot that you sometimes cannot even touch the steering wheel.

     This science project goes to show what affects our planet.

1. According to the text, the greenhouse effect appears mainly because of ________.

A. the hot sunlight         

B. chemicals around the Earth

C. the plastic bag     

D. human activities

2. Which of the following shows the right order of steps for the science project?_______

a. Measure the water which is not covered.

b. Make preparations for the project.

c. Fill each of the two glass containers with two cups of cold water.

d. Put one container in a plastic bag and close it tight.

e. Put the two containers in the sun for at least one hour.

f. Measure the water which is covered with a plastic bag.

A. b e d c a f      

B. b c d e f a   

C. b c e d a f    

D. b e c d f a

3. The writer mentions a car on a hot summer day to _______.

A. tell us about the hot weather in summer

B. prove the science project is correct

C. show the effects of the greenhouse effect

D. tell us how to protect cars during summer

4. If the story appears in a newspaper, the best title might be "________".

A. An Interesting Experiment Done by Kids

B. How to Protect Our Precious Planet

C. Bring Home the Seriousness of Greenhouse Effect

D. The Greenhouse Effect Has Been Proved by Kids

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