“纳米材料”是指微粒直径为几纳米（1nm=1×10-9m）到几十纳米的_爱下问搜题

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问题选择题

“纳米材料”是指微粒直径为几纳米（1nm=1×10^-9m）到几十纳米的材料．如将不同纳米材料分散到水中，得到的分散系具有的性质中，不可能有下列的（　　）

A．一定能通过半透膜

B．一定能通过滤纸

C．有丁达尔现象

D．有电泳现象

答案

胶体有以下性质：

1、胶体能产生丁达尔效应；

2、能透过滤纸不能透过半透膜；

3、胶粒带有电荷，能产生电泳现象；

故选A．

单项选择题 B1型题

肺脓肿（）。

A.X线胸片见单个薄壁空洞

B.X线胸片有偏心空洞，内壁凹凸不平

C.X线胸片呈大片状阴影，呈肺叶或肺段分布

D.X线胸片呈大片状阴影，内为单个空洞伴液平

E.X线胸片上肺有小片状阴影伴空洞

完形填空

One day my 5-year-old daughter, Mini, ran to the window crying: "A Cabuliwallah(喀布尔商贩)!A Cabuliwallah!" In the street below was Rahmun,a Cabuliwallah passing slowly along. Mini called him 21   ,but when he looked at her she ran away scared.    As time went by, they got to know each other and started to    22   together,
laughing and talking all the way. Rahmun would give her grapes and strawberries,spending the Iittle money he had 23   her. The two often enjoyed jokng together.Rahmun   24   say: "Well, little one, when are you going to the father-in-law's house?"Mini did not understand this and was   25    .
One morning,l saw Rahmun being led away by the police. There was some blood on his clothes .I   26 a neighbor had owed Rahmun money but denied it,and that in the course of the   27   Rahmun had struck him. On a charge of murderous attack, Rahmunwas   28   to prison.
Time passed. Mini grew up and we were making arrangements,for her 29    .I was sitting in my study   30   someone entered. It was Rahmun, his face pale and dirty and I could   31  recognize him! He said all those years ago Mini -had reminded him of his own daughter in Kabul. It was his belief that Mini was   32  the same. He  had   once   33   Mini running to him calling 66 A Cabuliwallah!" and pictured them laughing and talking together.
The two were now reunited. But when he made   34  once more, Mini's face turned red. They could not recover their old 35   .When Rahmun left, l gave him a bank note,   36  : "Go back to your own daughter, and may the happiness of your meeting bring good 37   to my child!"
Having made this present,I had to 38   the electric lights and the music band I had intended for the wedding and the ladies in the house were   39   .But to me the wedding was all the   40   for the thought that in a distant land a long-lost father met again with his child.

C．communication

C．suggestions

D．disappointed