下列有关釉质表面处理的描述，不正确的是（）
A.一般采用30%～50%磷酸水溶液预处理釉质
B.酸处理后釉质表面的羟基和氨基呈定向排列而使其表面呈极性
C.只有涉及釉柱中心的溶解才会使釉质表面变粗糙
D.釉质表面处理的目的是提高表面能，增强湿润效果
E.釉质表面与粘结剂树脂突结合是釉质与粘结剂之间的最主要的结合力
参考答案：C
解析：釉柱中心溶解、釉柱周围溶解以及无固定形式的溶解均可使牙釉质表面变粗糙。
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| When July comes, children know they'll have 1 examinations and the school year will end soon. Boys and girls will have a nearly two months' holiday, and they'll leave school 2 train or by car to 3 to see their fathers and mothers . The summer holidays are the 4 time of the year for most children. The weather is usually good, so one can 5 most of his time playing outside. If one lives in the country, he can 6 into the woods and in the fields. If one lives in a big town, he can usually go to a park to play. The best place for a summer holiday is the 7 . Some children are 8 enough to live near the sea. But for the others who do not, if they have the chance to stay at one of the big seaside towns for a week or two, they will talk about it all the following school year. Now, 9 makes children like the seaside so much? I think it is the sand, the sea and the sun, not anything else. Of course, there are 10 new things to see, nice things to eat, and interesting things to do. But the feeling of sand under their feet, of salt water on their skin, and the feeling of the warm sun on their backs make them happier. | |||
| ( ) 1. A. they ( ) 2. A. on ( ) 3. A. go to town ( ) 4. A. best ( ) 5. A. take ( ) 6. A. go out ( ) 7. A. village ( ) 8. A. lucky ( ) 9. A. that ( ) 10. A. little | B. them B. by B. go to the parks B. better B. use B. go on B. seaside B. sad B. which B. much | C. theirs C. in C. leave home C. worst C. spend C. go back C. city C. worried C. who C. lots of | D. their D. at D. return home D. worse D. waste D. go away D. park D. quiet D. what D. no |