制造南京长江大桥的材料是（） A.优质碳素结构钢 B.高合金钢 C.合金调质

某患者，男，60岁，与老同学聚餐时突然出现右侧肢体无力，随即摔倒，头痛剧烈，伴有呕吐，神志清醒，无言语不清，高血压13年。

应当首选的检查方法是（）

A.CT扫描

B.B超检查

C.MRI检查

D.血糖检查

E.脑电图检查

F.头部X线拍片

G.腰椎穿刺检查

诱导期长，汽油的氧化安定性就一定好。（）

Beijing: The United States and North Korea had their first (1) in four months here this afternoon as part of the (2) negotiations on how to end North Korea’s nuclear program, but diplomats played clown prospects for (3) . The talks are at the Diaoyutai (4) , a sprawling, garden-filled (5) in western Beijing, with negotiators gathering around a giant hexagonal table built to (6) the six delegations. The Chinese placed the Americans and the North Koreans in (7) , which may have facilitated the (8) between Mr. Kelly and Mr. Kim, which took place (9) in the afternoon session. The two spoke for 30 minutes, two Asian diplomats (10) . The early indications of how the talks are going (11) . A South Korean who took part in the meetings described North Korea as "willing to (12) through dialogue." Chinese officials also put a (13) on the talks. "I heard talks this morning and this afternoon were very successful," the Foreign Minister, Li Zhaoxing, told delegates (14) . But Japanese and Russian participants were (15) . The Russian (16) , Aleksandr Losyukov, described the negotiations as (17) . "So far, the countries have put forward a number of (18) , which are (19) the development of these talks," he told Russian reporters in Beijing. "I would not say that I am feeling (20) ."

清理商标纸涂胶器是日保的内容之一。

在火灾中，没有防火保护的受力钢构件极易受高温变形，当温度升至300℃时，钢材的强度即开始逐渐下降，通常在（）后，结构就会倒塌。

A.15～30min

B.15～60min

C.1h

D.2h